WorldWideScience

Sample records for high background levels

  1. 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)

  2. High-level radioactive waste in Canada. Background paper

    International Nuclear Information System (INIS)

    Fawcett, R.

    1993-11-01

    The disposal of radioactive waste is one of the most challenging environmental problems facing Canada today. Since the Second World War, when Canadian scientists first started to investigate nuclear reactions, there has been a steady accumulation of such waste. Research reactors built in the early postwar years produced small amounts of radioactive material but the volume grew steadily as the nuclear power reactors constructed during the 1960s and 1970s began to spawn used fuel bundles. Although this radioactive refuse has been safely stored for the short term, no permanent disposal system has yet been fully developed and implemented. Canada is not alone in this regard. A large number of countries use nuclear power reactors but none has yet put in place a method for the long-term disposal of the radioactive waste. Scientists and engineers throughout the world are investigating different possibilities; however, enormous difficulties remain. In Canada, used fuel bundles from nuclear reactors are defined as high-level waste; all other waste created at different stages in the nuclear fuel cycle is classified as low-level. Although disposal of low-level waste is an important issue, it is a more tractable problem than the disposal of high-level waste, on which this paper will concentrate. The paper discusses the nuclear fuel waste management program in Canada, where a long-term disposal plan has been under development by scientists and engineers over the past 15 years, but will not be completed for some time. Also discussed are responses to the program by parliamentary committees and aboriginal and environmental groups, and the work in the area being conducted in other countries. (author). 1 tab

  3. High-level radioactive waste in Canada. Background paper

    Energy Technology Data Exchange (ETDEWEB)

    Fawcett, R [Library of Parliament, Ottawa, ON (Canada). Science and Technology Div.

    1993-11-01

    The disposal of radioactive waste is one of the most challenging environmental problems facing Canada today. Since the Second World War, when Canadian scientists first started to investigate nuclear reactions, there has been a steady accumulation of such waste. Research reactors built in the early postwar years produced small amounts of radioactive material but the volume grew steadily as the nuclear power reactors constructed during the 1960s and 1970s began to spawn used fuel bundles. Although this radioactive refuse has been safely stored for the short term, no permanent disposal system has yet been fully developed and implemented. Canada is not alone in this regard. A large number of countries use nuclear power reactors but none has yet put in place a method for the long-term disposal of the radioactive waste. Scientists and engineers throughout the world are investigating different possibilities; however, enormous difficulties remain. In Canada, used fuel bundles from nuclear reactors are defined as high-level waste; all other waste created at different stages in the nuclear fuel cycle is classified as low-level. Although disposal of low-level waste is an important issue, it is a more tractable problem than the disposal of high-level waste, on which this paper will concentrate. The paper discusses the nuclear fuel waste management program in Canada, where a long-term disposal plan has been under development by scientists and engineers over the past 15 years, but will not be completed for some time. Also discussed are responses to the program by parliamentary committees and aboriginal and environmental groups, and the work in the area being conducted in other countries. (author). 1 tab.

  4. China's deep geological disposal program for high level radioactive waste, background and status 1998

    International Nuclear Information System (INIS)

    Ju Wang; Xu Guoqing; Guo Yonghai

    2001-01-01

    This paper presents the background and progress made in the study of China's high level radioactive waste, including site screening, site evaluation, the study on radionuclide migration, bentonite, natural analogue studies, and performance assessment, etc. The study on Beishan area, the potential area for China's geological repository, is also presented in this paper. (author)

  5. Measurement of high natural background radiation levels by TLD at Cox's Bazar coastal areas in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.; Rahman, M.M.; Koddus, M.A.; Husain, S.R.; Malek, M.A.

    1987-01-01

    High natural background radiation levels at the Cox's Bazar coastal areas in Bangladesh were measured by LiF (TLD-100) dosemeters. The dose rates varied from 2621 to 35391 μGy.y -1 with a mean of 11968 μGy.y -1 . The average dose rate is found to significantly higher than the world average value. In order to formulate appropriate guidelines for radiation protection of the population in this area, the necessary recommendations are described. (author)

  6. Cytogenetic studies on newborns from high level natural background radiation areas of Kerala coast, South India

    International Nuclear Information System (INIS)

    Cherian, V.D.; Kurien, C.J.; Das, Birajalaxmi

    1997-01-01

    The human population residing in the monazite bearing high level natural background radiation (HLNBR) areas of Kerala, along the South-West coast of India provides unique opportunities of assessing directly in man, the health effects of chronic low-level radiation exposure. The per capita dose received by this population is nearly four times the normal background radiation level. While this is the average dose, the radiation levels prevailing in these HLNBR areas are in the range of 1 to over 35 mGy per year. Chromosomal aberration studies in the lymphocytes of newborns and adults from these areas have been in progress for two decades. So far, 4156 newborn babies from HLNBR and 7321 from normal background radiation (NBR) areas have been screened for the incidence of chromosomal aberrations (dicentrics and rings). The mean frequency of dicentrics and rings did not show any significant difference between the newborns in the control and the HLNBRA population. Assessment of the frequency of micronuclei in cytochalasin-B blocked binucleated lymphocytes of 49 newborns from control areas and 131 newborns from radioactive areas also showed similar values. While an age-dependent increase in chromosome aberration frequency was observed in the adult samples from control and the study areas, the regression analysis of the data indicated a marginally higher slope for the samples from HLNBRA. Karyotype anomalies recorded so far among the newborns have not revealed any significant difference in the incidence of numerical (including Down syndrome) and structural alterations between the control and the exposed populations. A noteworthy observation, herein reported for the first time from any HLNBR area is that there is no discernible increase in the incidence of micronuclei and chromosomal aberrations in the peripheral lymphocytes of newborn babies hailing from HLNBR areas, where their ancestral generations have lived for several hundreds of years. (author)

  7. Background noise levels in Europe

    OpenAIRE

    Gjestland, Truls

    2008-01-01

    - This report gives a brief overview of typical background noise levels in Europe, and suggests a procedure for the prediction of background noise levels based on population density. A proposal for the production of background noise maps for Europe is included.

  8. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    International Nuclear Information System (INIS)

    Ramola, R. C.; Gusain, G. S.; Rautela, B. S.; Sagar, D. V.; Prasad, G.; Shahoo, S. K.; Ishikawa, T.; Omori, Y.; Janik, M.; Sorimachi, A.; Tokonami, S.

    2012-01-01

    Exposure to radon, 222 Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, 220 Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to 220 Rn and its progeny can equal or several time exceed that of 220 Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha (India)) presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper. (authors)

  9. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    Energy Technology Data Exchange (ETDEWEB)

    Ramola, R C; Gusain, G S; Rautela, B S [Dept. of Physics, H.N.B. Garhwal Univ., Badshahi Thaul Campus, Tehri Garhwal 249199 (India); Sagar, D V [Health Physics Unit EAD, BARC, IRE, OSCOM, Matikhalo, Ganjam, Odisha 761 045 (India); Prasad, G; Shahoo, S K; Ishikawa, T; Omori, Y; Janik, M [National Inst. of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555 (Japan); Sorimachi, A; Tokonami, S [Inst. of Radiation Emergency Medicine, Hirosaki Univ., Aomori 036-8564 (Japan)

    2012-07-01

    Exposure to radon, {sup 222}Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, {sup 220}Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to {sup 220}Rn and its progeny can equal or several time exceed that of {sup 220}Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha (India)) presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper. (authors)

  10. High-level radioactive waste management in the United States. Background and status: 1996

    International Nuclear Information System (INIS)

    Dyer, J.R.

    1996-01-01

    The US high-level radioactive waste disposal program is investigating a site at Yucca Mountain, Nevada, to determine whether or not it is a suitable location for the development of a deep mined geologic repository. At this time, the US program is investigating a single site, although in the past, the program involved successive screening and comparison of alternate locations. The United States civilian reactor programs do not reprocess spent fuel; the high-level waste repository will be designed for the emplacement or spent fuel and a limited amount of vitrified high-level wastes from previous reprocessing in the US. The legislation enabling the US program also contains provisions for a Monitored Retrievable Storage facility, which could provide temporary storage of spent fuel accepted for disposal, and improve the flexibility of the repository development schedule

  11. 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)

  12. Dose for background radioactivity in areas with high radioactivity levels in the Pinar del Rio province

    International Nuclear Information System (INIS)

    Alcaide Orpi, J.; Oliveira Acosta, J.; Valdes Hernadez, G.M.; Leal Ramirez, M.R.; Blanco Jorrin, N.

    1998-01-01

    The objective the work is to know the areas with high natural radiation doses, for they were used it the data obtained by the studies it has more than enough favorability for radioactive minerals carried out in different regions to the Pinar del Rio province in the 1986 to 1993 years and the doses calculations they were carried out according to the effective methodology

  13. Radioecology teaching: evaluation of the background radiation levels from areas with high concentrations of radionuclides in soil

    International Nuclear Information System (INIS)

    Anjos, R M; Okuno, E; Gomes, P R S; Veiga, R; Estellita, L; Mangia, L; Uzeda, D; Soares, T; Facure, A; Brage, J A P; Mosquera, B; Carvalho, C; Santos, A M A

    2004-01-01

    The study of environmental radioactivity is a topic which is not usually included in physics courses in Brazilian and Latin American universities. Consequently, high-school teachers are not able to show experimentally or discuss with their students the effects of exposure to terrestrial radiation. This paper presents a laboratory experiment in a teaching programme on the physics of ionizing radiation. It is based on the evaluation of the background radiation levels from areas with high concentrations of natural or artificial radionuclides in the soil. A brief analysis of the theory behind the technique and a description of some measurements, including their interpretations, are presented

  14. Some historical background to the IAEA Definition and Recommendations concerning high-level radioactive wastes or other high-level radioactive matter unsuitable for dumping at sea

    International Nuclear Information System (INIS)

    Nishiwaki, Y.

    1981-01-01

    The need for internationally acceptable standards and regulations for preventing pollution of the sea by radioactive materials was recognized by the United Nations Conference on the Law of the Sea, which adopted the Convention on the High Seas in April 1958. Article 25 of the Convention provides that ''every State shall take measures to prevent pollution of the seas from the dumping of radioactive wastes, taking into account any standards and regulations which may be formulated by the competent international organizations.'' The Conference also adopted a resolution recommending that the IAEA pursue studies and take action to assist States in controlling the discharge of radioactive materials into the sea. When the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter was adopted at the Intergovernmental Conference in London, 1972, the IAEA was given specific responsibilities to define criteria and standards for dealing with the questions of sea disposal of radioactive wastes. The IAEA Definition and Recommendations concerning ''high-level radioactive wastes or other high-level radioactive matter unsuitable for dumping at sea'' identify material, the radioactive content of which is at such a level that the Parties to the Convention would wish to prevent any participating State from issuing a special permit even after a detailed appraisal of the safety of the proposed operation, and even for the sector of the marine environment furthest removed from man, i.e. the deep sea with depth greater than 4000 m. Some historical background to these problems is discussed and some of the Japanese findings of the deep sea survey in the Pacific are introduced for comparison with the North Atlantic data which formed a basis of the IAEA Definition and Recommendations for the London Dumping Convention

  15. Biological effects of high level natural background radiation on human population residing in Kerala coast, South West India

    International Nuclear Information System (INIS)

    Seshadri, M.

    2010-01-01

    The populations residing in Kerala coast are exposed to elevated natural background radiation since many generations. Extensive studies conducted by Bio-Medical group, Bhabha Atomic Research Center have generated wealth of data from this area dealing with epidemiology, monitoring the newborns for malformations, Health Audit Survey, Dosimetry and biological studies using cytogenetic and molecular biology techniques. Our studies on congenital malformations and chromosomal anomalies in children born to parents residing in High Level Natural Radiation Areas in Kerala have not shown any significant difference from normal radiation areas. Screening of over 1,25,000 consecutively born children showed an incidence rate which is comparable in both areas. Other factors such as consanguinity, maternal age and gravida status are more significant contributors than radiation dose to the risk for having malformation in child. Radiation prevalent in the HLNRA is in the dose range of above 1.5 to about 50 mGy per year which translates to doses in the range of nGy per hour. This clearly indicate the number of cells exposed to radiations will be one in few thousand or ten thousands. This throws up challenges in our capability to investigate the effects of radiation on cells. It has become imperative to develop and exploit techniques which will detect responses in single cells and would be able screen large number of cells at a time. Developments in cell biology and molecular biology are now giving us these capabilities. Use of flowcytometer and next generation sequencing would enable us to address many of these questions and provide meaningful approaches to understand the effects of such low dose radiation

  16. Long-lived legacy: Managing high-level and transuranic waste at the DOE Nuclear Weapons Complex. Background paper

    International Nuclear Information System (INIS)

    1991-05-01

    The document focuses on high-level and transuranic waste at the DOE nuclear weapons complex. Reviews some of the critical areas and aspects of the DOE waste problem in order to provide data and further analysis of important issues. Partial contents, High-Level Waste Management at the DOE Weapons Complex, are as follows: High-Level Waste Management: Present and Planned; Amount and Distribution; Current and Potential Problems; Vitrification; Calcination; Alternative Waste Forms for the Idaho National Engineering Laboratory; Technologies for Pretreatment of High-Level Waste; Waste Minimization; Regulatory Framework; Definition of High-Level Waste; Repository Delays and Contingency Planning; Urgency of High-Level Tank Waste Treatment; Technologies for High-Level Waste Treatment; Rethinking the Waste Form and Package; Waste Form for the Idaho National Engineering Laboratory; Releases to the Atmosphere; Future of the PUREX Plant at Hanford; Waste Minimization; Tritium Production; International Cooperation; Scenarios for Future HLW Production. Partial contents of Chapter 2, Managing Transuranic Waste at the DOE Nuclear Weapons Complex, are as follows: Transuranic Waste at Department of Energy Sites; Amount and Distribution; Waste Management: Present and Planned; Current and Potential Problems; Three Technologies for Treating Retrievably Stored Transuranic Waste; In Situ Vitrification; The Applied Research, Development, Demonstration, Testing, and Evaluation Plan (RDDT ampersand E); Actinide Conversion (Transmutation); Waste Minimization; The Regulatory Framework; Definition of, and Standards for, Disposal of Transuranic Waste; Repository Delays; Alternative Storage and Disposal Strategies; Remediation of Buried Waste; The Waste Isolation Pilot Plant; Waste Minimization; Scenarios for Future Transuranic Waste Production; Conditions of No-Migration Determination

  17. A novel background reduction strategy for high level triggers and processing in gamma-ray Cherenkov detectors

    OpenAIRE

    Cabras, G.; De Angelis, A.; De Lotto, B.; De Maria, M. M.; De Sabata, F.; Mansutti, O.; Frailis, M.; Persic, M.; Bigongiari, C.; Doro, M.; Mariotti, M.; Peruzzo, L.; Saggion, A.; Scalzotto, V.; Paoletti, R.

    2008-01-01

    Gamma ray astronomy is now at the leading edge for studies related both to fundamental physics and astrophysics. The sensitivity of gamma detectors is limited by the huge amount of background, constituted by hadronic cosmic rays (typically two to three orders of magnitude more than the signal) and by the accidental background in the detectors. By using the information on the temporal evolution of the Cherenkov light, the background can be reduced. We will present here the results obtained wit...

  18. A novel background reduction strategy for high level triggers and processing in gamma-ray Cherenkov detectors

    International Nuclear Information System (INIS)

    Cabras, G.; De Angelis, A.; De Lotto, B.; De Maria, M. M.; De Sabata, F.; Mansutti, O.; Frailis, M.; Persic, M.; Bigongiari, C.; Doro, M.; Mariotti, M.; Peruzzo, L.; Saggion, A.; Scalzotto, V.; Paoletti, R.; Scribano, A.; Turini, N.; Moralejo, A.; Tescaro, D.

    2008-01-01

    Gamma ray astronomy is now at the leading edge for studies related both to fundamental physics and astrophysics. The sensitivity of gamma detectors is limited by the huge amount of background, constituted by hadronic cosmic rays (typically two to three orders of magnitude more than the signal) and by the accidental background in the detectors. By using the information on the temporal evolution of the Cherenkov light, the background can be reduced. We will present here the results obtained within the MAGIC experiment using a new technique for the reduction of the background. Particle showers produced by gamma rays show a different temporal distribution with respect to showers produced by hadrons; the background due to accidental counts shows no dependence on time. Such novel strategy can increase the sensitivity of present instruments

  19. 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.

  20. Measurements of incoherent light and background structure at exo-Earth detection levels in the High Contrast Imaging Testbed

    Science.gov (United States)

    Cady, Eric; Shaklan, Stuart

    2014-08-01

    A major component of the estimation and correction of starlight at very high contrasts is the creation of a dark hole: a region in the vicinity of the core of the stellar point spread function (PSF) where speckles in the PSF wings have been greatly attenuated, up to a factor of 1010 for the imaging of terrestrial exoplanets. At these very high contrasts, removing these speckles requires distinguishing between light from the stellar PSF scattered by instrument imperfections, which may be partially corrected across a broad band using deformable mirrors in the system, from light from other sources which generally may not. These other sources may be external or internal to the instrument (e.g. planets, exozodiacal light), but in either case, their distinguishing characteristic is their inability to interfere coherently with the PSF. In the following we discuss the estimation, structure, and expected origin of this incoherent" signal, primarily in the context of a series of experiments made with a linear band-limited mask in Jan-Mar 2013. We find that the incoherent" signal at moderate contrasts is largely estimation error of the coherent signal, while at very high contrasts it represents a true floor which is stable over week-timescales.

  1. Role of light and heavy minerals on natural radioactivity level of high background radiation area, Kerala, India.

    Science.gov (United States)

    Ramasamy, V; Sundarrajan, M; Suresh, G; Paramasivam, K; Meenakshisundaram, V

    2014-02-01

    Natural radionuclides ((238)U, (232)Th and (40)K) concentrations and eight different radiological parameters have been analyzed for the beach sediments of Kerala with an aim of evaluating the radiation hazards. Activity concentrations ((238)U and (232)Th) and all the radiological parameters in most of the sites have higher values than recommended values. The Kerala beach sediments pose significant radiological threat to the people living in the area and tourists going to the beaches for recreation or to the sailors and fishermen involved in their activities in the study area. In order to know the light mineral characterization of the present sediments, mineralogical analysis has been carried out using Fourier transform infrared (FTIR) spectroscopic technique. The eight different minerals are identified and they are characterized. Among the various observed minerals, the minerals such as quartz, microcline feldspar, kaolinite and calcite are major minerals. The relative distribution of major minerals is determined by calculating extinction co-efficient and the values show that the amount of quartz is higher than calcite and much higher than microcline feldspar. Crystallinity index is calculated to know the crystalline nature of quartz present in the sediments. Heavy mineral separation analysis has been carried out to know the total heavy mineral (THM) percentage. This analysis revealed the presence of nine heavy minerals. The minerals such as monazite, zircon, magnetite and illmenite are predominant. Due to the rapid and extreme changes occur in highly dynamic environments of sandy beaches, quantities of major light and heavy minerals are widely varied from site to site. Granulometric analysis shows that the sand is major content. Multivariate statistical (Pearson correlation, cluster and factor) analysis has been carried out to know the effect of mineralogy on radionuclide concentrations. The present study concluded that heavy minerals induce the (238)U and (232)Th

  2. Technical reliability of geological disposal for high-level radioactive wastes in Japan. The second progress report. An extra issue: background of the geological disposal

    International Nuclear Information System (INIS)

    1999-11-01

    Based on the Advisory Committee Report on Nuclear Fuel Cycle Backend Policy submitted to the Japanese Government in 1997, JNC documents the progress of research and development program in the form of the second progress report (the first one published in 1992). It summarizes an evaluation of the technical reliability and safety of the geological disposal concept for high-level radioactive wastes (HLW) in Japan. The present document, an extra issue of the progress report, was prepared for the expected readers of the report to have background information on the geological disposal. Thus it gives information about (1) generation of high-level radioactive wastes, (2) history of plans proposed for HLW disposal in Japan, and (3) procedure until the geological disposal plan is finally adopted and basic future schedules. It further discusses on such problems in HLW treatment and disposal, as for example a problem of reliable safety for a very long period. (Ohno, S.)

  3. Epidemiology of non-syndromic cleft lip/palate in the high level natural background radiation areas (HLNRA) of the South west coast of India

    International Nuclear Information System (INIS)

    Jaikrishan, G.; Sudheer, K.R.; Andrews, V.J.; Koya, P.K.M.; Cheriyan, V.D.; Seshadri, M.

    2010-01-01

    All consecutive births in selected government hospitals in and around the high level natural background radiation areas (HLNRA) of Kerala were monitored for congenital malformations observable at birth since 1995. The HLNR area, with natural deposits of monazite sand containing thorium (8-10%) and Uranium (0.3%), is a coastal strip of land about 55 km in length and 0.5 km in breadth from Purakkad in the north in Alleppey district to Sakthikulangara in the south of Quilon district and is one among the most prominent background radiation areas of the world. Patchy and non-uniform distribution of Monazite sand causes wide variation in dose ranging from <1 to 45 mGy/year. High population density, limited migration, ethnic diversity, good literacy, health awareness, institutionalized births and acceptance of small family norm are some of the key features of the population. Areas with a mean radiation dose of more than 1.5 mGy/year were treated as HLNR areas and areas with a dose level of 1.5 mGy/year or less were treated as normal level radiation areas (NLNRA). A total of 134,178 newborns were monitored and non-syndromic cleft lip/palate (NSCLP) was detected in 143 newborns (1.07%). Cleft lip with cleft palate (59.4%) was more common than cleft lip (18.2%) or Cleft palate (22.4%) alone and 11.9% had other malformation(s) together with NSCLP. There was no evidence to suggest that NSFC was significantly associated with prevailing dose level of area of mother's residence, maternal age birth, gravida, ethnicity or consanguinity

  4. 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

  5. High Octane Fuel: Terminal Backgrounder

    Energy Technology Data Exchange (ETDEWEB)

    Moriarty, Kristi [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-02-11

    The Bioenergy Technologies Office of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy sponsored a scoping study to assess the potential of ethanol-based high octane fuel (HOF) to reduce energy consumption and greenhouse gas emissions. When the HOF blend is made with 25%-40% ethanol by volume, this energy efficiency improvement is potentially sufficient to offset the reduced vehicle range often associated with the decreased volumetric energy density of ethanol. The purpose of this study is to assess the ability of the fuel supply chain to accommodate more ethanol at fuel terminals. Fuel terminals are midstream in the transportation fuel supply chain and serve to store and distribute fuels to end users. While there are no technical issues to storing more ethanol at fuel terminals, there are several factors that could impact the ability to deploy more ethanol. The most significant of these issues include the availability of land to add more infrastructure and accommodate more truck traffic for ethanol deliveries as well as a lengthy permitting process to erect more tanks.

  6. NATURAL RADIOACTIVITY LEVEL AND ELEMENTAL COMPOSITION OF SOIL SAMPLES FROM A HIGH BACKGROUND RADIATION AREA ON EASTERN COAST OF INDIA (ODISHA).

    Science.gov (United States)

    Sahoo, S K; Kierepko, R; Sorimachi, A; Omori, Y; Ishikawa, T; Tokonami, S; Prasad, G; Gusain, G S; Ramola, R C

    2016-10-01

    A comprehensive study was carried out to determine the radioactivity concentration of soil samples from different sites of a high background radiation area in the eastern coast of India, Odisha state. The dose rate measured in situ varied from 0.25 to 1.2 µSv h -1 The gamma spectrometry measurements indicated Th series elements as the main contributors to the enhanced level of radiation and allowed the authors to find the mean level of the activity concentration (±SD) for 226 Ra, 228 Th and 40 K as 130±97, 1110±890 and 360±140 Bq kg -1 , respectively. Human exposure from radionuclides occurring outdoor was estimated based on the effective dose rate, which ranged from 0.14±0.02 to 2.15±0.26 mSv and was higher than the UNSCEAR annual worldwide average value 0.07 mSv. Additionally, X-ray fluorescence analysis provided information about the content of major elements in samples and indicated the significant amount of Ti (7.4±4.9 %) in soils. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Measurement of Acceptable Noise Level with Background Music.

    Science.gov (United States)

    Ahn, Hyun-Jung; Bahng, Junghwa; Lee, Jae Hee

    2015-09-01

    Acceptable noise level (ANL) is a measure of the maximum background noise level (BNL) that a person is willing to tolerate while following a target story. Although researchers have used various sources of target sound in ANL measures, a limited type of background noise has been used. Extending the previous study of Gordon-Hickey & Moore (2007), the current study determined the effect of music genre and tempo on ANLs as possible factors affecting ANLs. We also investigated the relationships between individual ANLs and the familiarity of music samples and between music ANLs and subjective preference. Forty-one participants were seperated into two groups according to their ANLs, 29 low-ANL listeners and 12 high-ANL listeners. Using Korean ANL material, the individual ANLs were measured based on the listeners' most comfortable listening level and BNL. The ANLs were measured in six conditions, with different music tempo (fast, slow) and genre (K-pop, pop, classical) in a counterbalanced order. Overall, ANLs did not differ by the tempo of background music, but music genre significantly affected individual ANLs. We observed relatively higher ANLs with K-pop music and relatively lower ANLs with classical music. This tendency was similar in both low-ANL and high-ANL groups. However, the subjective ratings of music familiarity and preference affected ANLs differently for low-ANL and high-ANL groups. In contrast to the low-ANL listeners, the ANLs of the high-ANL listeners were significantly affected by music familiarity and preference. The genre of background music affected ANLs obtained using background music. The degree of music familiarity and preference appears to be associated with individual susceptibility to background music only for listeners who are greatly annoyed by background noise (high-ANL listeners).

  8. 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

  9. Overcoming High Energy Backgrounds at Pulsed Spallation Sources

    CERN Document Server

    Cherkashyna, Nataliia; DiJulio, Douglas D.; Khaplanov, Anton; Pfeiffer, Dorothea; Scherzinger, Julius; Cooper-Jensen, Carsten P.; Fissum, Kevin G.; Ansell, Stuart; Iverson, Erik B.; Ehlers, Georg; Gallmeier, Franz X.; Panzner, Tobias; Rantsiou, Emmanouela; Kanaki, Kalliopi; Filges, Uwe; Kittelmann, Thomas; Extegarai, Maddi; Santoro, Valentina; Kirstein, Oliver; Bentley, Phillip M.

    2015-01-01

    Instrument backgrounds at neutron scattering facilities directly affect the quality and the efficiency of the scientific measurements that users perform. Part of the background at pulsed spallation neutron sources is caused by, and time-correlated with, the emission of high energy particles when the proton beam strikes the spallation target. This prompt pulse ultimately produces a signal, which can be highly problematic for a subset of instruments and measurements due to the time-correlated properties, and different to that from reactor sources. Measurements of this background have been made at both SNS (ORNL, Oak Ridge, TN, USA) and SINQ (PSI, Villigen, Switzerland). The background levels were generally found to be low compared to natural background. However, very low intensities of high-energy particles have been found to be detrimental to instrument performance in some conditions. Given that instrument performance is typically characterised by S/N, improvements in backgrounds can both improve instrument pe...

  10. High level expression and characterization of tannase tan7 using Aspergillus niger SH-2 with low-background endogenous secretory proteins as the host.

    Science.gov (United States)

    Liu, Fengling; Wang, Bin; Ye, Yanrui; Pan, Li

    2018-04-01

    Tannin acyl hydrolase (tannase, EC3.1.1.20) catalyzes the hydrolysis of hydrolyzable tannins. It is used in the manufacture of instant tea and in the production of gallic acid. In this study, we reported that the overexpression, purification and characterization of an Aspergillus niger tannase. The tannase gene was cloned from A. niger SH-2 and expressed in the A. niger strain Bdel4 which is low-background of secreted proteins. The recombinant tannase was purified by desalting, followed by gel filtration for characterization. The tannase activity achieved 111.5 U/mL at 168 h, and the purity of the enzyme in the broth supernatant was estimated to be over 70%. The optimum temperature and pH of the recombinant tannase was ∼40 °C and 7.0, respectively. The tannase activity was inhibited by Mg 2+ , Ca 2+ , Cu 2+ , Ba 2+ , Ni 2+ and EDTA, and was enhanced by Mn 2+ and Co 2+ . Since A. niger is a GRAS microorganism, the recombinant tannase could be purification-free due to its high purity. The results of this study suggested that this recombinant strain could be subjected to large-scale production of A. niger tannase. Copyright © 2017. Published by Elsevier Inc.

  11. Environmental 238U and 232Th concentration measurements in an area of high level natural background radiation at Palong, Johor, Malaysia.

    Science.gov (United States)

    Ramli, A Termizi; Hussein, A Wahab M A; Wood, A Khalik

    2005-01-01

    Concentrations of uranium-238 and thorium-232 in soil, water, grass, moss and oil-palm fruit samples collected from an area of high background radiation were determined using neutron activation analysis (NAA). U-238 concentration in soil ranged from 4.9 mg kg(-1) (58.8 Bq kg(-1)) to 40.4 mg kg(-1) (484.8 Bq kg(-1)), Th-232 concentration ranged from 14.9 mg kg(-1) (59.6 Bq kg(-1)) to 301.0 mg kg(-1) (1204 Bq kg(-1)). The concentration of U-238 in grass samples ranged from below the detection limit to 0.076 mg kg(-1) (912 mBq kg(-1)), and Th-232 ranged from 0.008 mg kg(-1) (32 mBq kg(-1)) to 0.343 mg kg(-1) (1.372 Bq kg(-1)). U-238 content in water samples ranged from 0.33 mg kg(-1) (4.0 Bq L(-1)) to 1.40 mg kg(-1) (16.8 Bq L(-1)), and Th-232 ranged from 0.19 mg kg(-1) (0.76 Bq L(-1)) to 0.66 mg kg(-1) (2.64 Bq L(-1)). It can be said that the concentrations of environmental U-238 and Th-232 in grass and water samples in the study area are insignificant. Mosses were found to be possible bio-radiological indicators due to their high absorption of the heavy radioelements from the environment.

  12. The semi-empirical low-level background statistics

    International Nuclear Information System (INIS)

    Tran Manh Toan; Nguyen Trieu Tu

    1992-01-01

    A semi-empirical low-level background statistics was proposed. The one can be applied to evaluated the sensitivity of low background systems, and to analyse the statistical error, the 'Rejection' and 'Accordance' criteria for processing of low-level experimental data. (author). 5 refs, 1 figs

  13. Environmental background level of cosmic ray produced 22Na

    International Nuclear Information System (INIS)

    Tokuyama, H.; Oonishi, M.; Matsuura, H.

    1993-01-01

    The annual deposition rate of cosmogenic 22 Na has been studied at Fukui City, Japan, to obtain the current background level. The deposition rate was found to range from 0.16 to 0.22 Bq m -2 y -1 with a mean value of 0.20 Bq m -2 y -1 for the years 1986-1990. The author's results agree fairly well with those observed for the years 1975-1977 in Tokyo. The 22 Na concentration in rain water was also estimated. The mean value for this period was found to be 0.09 mBq litre -1 , which is about one-third of that detected during the latter half of the 1950's. The high levels of environmental 22 Na in the 1950's are attributed to the many nuclear weapon tests conducted at that time. At present, however, the 22 Na from these weapons tests has practically decayed and the concentration in rain water has decreased to the natural background level. (Author)

  14. 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.

  15. Epidemiological studies in high background radiation areas

    International Nuclear Information System (INIS)

    Akiba, Suminori

    2012-01-01

    Below the doses of 100-200 mSv of radiation exposure, no acute health effect is observed, and the late health effects such as cancer are yet unclear. The problems making the risk evaluation of low dose radiation exposure difficult are the fact that the magnitude of expected health effects are small even if the risk is assumed to increase in proportion to radiation doses. As a result, studies need to be large particular when dealing with rare disease such as cancer. In addition, the expected health effects are so small that they can easily be masked by lifestyles and environmental factors including smoking. This paper will discuss cancer risk possibly associated with low-dose and low-dose rate radiation exposure, describing epidemiological studies on the residents in the high-background radiation areas. (author)

  16. Cosmic microwave background distortions at high frequencies

    International Nuclear Information System (INIS)

    Peter, W.; Peratt, A.L.

    1988-01-01

    The authors analyze the deviation of the cosmic background radiation spectrum from the 2.76+-0.02 0 Κ blackbody curve. If the cosmic background radiation is due to absorption and re-emission of synchrotron radiation from galactic-width current filaments, higher-order synchrotron modes are less thermalized than lower-order modes, causing a distortion of the blackbody curve at higher frequencies. New observations of the microwave background spectrum at short wavelengths should provide an indication of the number of synchrotron modes thermalized in this process. The deviation of the spectrum from that of a perfect blackbody can thus be correlated with astronomical observations such as filament temperatures and electron energies. The results are discussed and compared with the theoretical predictions of other models which assume the presence of intergalactic superconducting cosmic strings

  17. Health effects in residents of regions with high background radiation

    International Nuclear Information System (INIS)

    Hanson, G.P.

    1984-01-01

    Possible health problems created by high natural levels of background radiation are hard to detect, partly because the health problems involved would exist to some degree irrespective of radiation exposure, partly because other factors affect the incidence of such problems, and partly because the differences between normal background radiation levels and radiation levels found in most high-radiation areas are not extreme. Nevertheless, the need to know about such health effects is evident, and so various studies conducted over the past 30 years have sought to determine whether those effects exist and what they are. Overall, however, the fragmentary and uncertain nature of many of these findings makes it hard to draw firm conclusions about the health risks involved or the desirability of countermeasures. So despite considerable efforts and some progress over the past three decades, the need for a clear quantitative assessment of the consequences is as great as ever

  18. 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

  19. Trace gases over Northern Eurasia: background level and disturbing factors

    Science.gov (United States)

    Skorokhod, A.; Shumsky, R.; Pankratova, N.; Moiseenko, K.; Vasileva, A.; Berezina, E.; Elansky, N.

    2012-04-01

    Atmospheric air composition over the vast and low inhabited areas of Northern Eurasia is still poorly studied because of lack of the precise direct measurements. This harms to accuracy of both global and regional models which simulate climatological and ecosystem changes in that highly important region. In this work background trace gases (such as O3, NO, NO2, CO) concentrations and their variability are considered on base of results of continuous measurements at ZOTTO station in the middle of Siberia which have been carried out since March, 2007. Also factors implying background regime (like long-range transport, wild fires emissions) are analyzed. To compliment study data of TROICA train-based campaigns which have been regularly provided across Russia for many years (1995-2010) are used. The concentration of ozone has a pronounced seasonal variation with a clear peak in spring (40-45 ppbv in average and up to 80 ppbv in extreme cases) and minimum in winter. Average ozone level is about 20 ppbv that corresponds to the background conditions. Enhanced concentration in March-July is due to increased stratospheric-tropospheric exchange. In autumn and winter distribution of ozone is close to uniform. Photochemical processes under low light and air temperature does not cause the generation of ozone. Sink on the snow surface is very small, and therefore the diurnal variations are absent. In general, seasonal variations correspond to the average seasonal course, which is typical for Russia. The analysis of diurnal ozone variations in Zotino in different seasons showed that the maximum rate of ozone formation is observed in summer from 9 to 15 h local time and is 1-2 ppbv/hour. It correlates well with the data on the isoprene emissions and others biogenic VOC reacting with OH- radical. Thus they are biogenic VOC emissions that seem to be the main factor of the lower troposphere oxidation power in summer. In other seasons it is significantly lower. NOx concentration does

  20. Astronomy: social background of students of the integrated high school

    Science.gov (United States)

    Voelzke, M. R.; Barbosa, J. I. L.

    2017-07-01

    Astronomy-related contents exist in almost all levels of basic education in Brazil and are also frequently disseminated through mass media. Thus, students form their own explanations about the phenomena studied by this science. Therefore, this work has the objective of identifying the possible social background of the Integrated High School students on the term Astronomy. It is a research of a basic nature, descriptive, and for that reason a quali-quantitative approach was adopted; the procedures to obtain the data were effected in the form of a survey. The results show that the tested students have a social background about the object Astronomy, which is on the one hand fortified by elements they have made or which is part of the experience lived by the respondents within the formal space of education, and on the other hand based on elements possibly disseminated through the mass media.

  1. Backgrounder

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    Safe and Inclusive Cities: ... improving urban environments and public spaces might have on reducing the city's high ... violence against women among urban youth of working class neighbourhoods of Islamabad, Rawalpindi, and Karachi,.

  2. Environmental background 14C levels in Japan in 1990s

    International Nuclear Information System (INIS)

    Fuma, Shoichi; Inoue, Yoshikazu; Miyamoto, Kiriko; Takeda, Hiroshi; Iwakura, Tetsuo; Arai, Kiyohiko; Kashida, Yoshihiko; Ichimasa, Yusuke

    2002-01-01

    For assessment of radiation doses due to 14 C released from nuclear facilities, it is necessary to know the background level of environmental 14 C originated from the natural cosmic-ray production and the past atmospheric nuclear weapons tests. The authors selected grapes as an indicator of 14 C levels in the environment including atmosphere, and determined the specific activities of 14 C in ethanol extracted from wine made from grapes cultivated in several prefectures or unknown places in Japan in each year from 1990 to 2000. The specific activities of 14 C were almost uniform all over Japan in each year, though they showed the weak tendency to slightly decrease with increasing population densities in the prefecture where the wine grapes were cultivated. It is considered that this small regional variation in the specific activities of 14 C arose from Suess effect, because population densities can be regarded as an index of the amount of CO 2 emission from fossil-fuel combustion. The specific activities of 14 C gradually decreased in the 1990s. That is, they were 260 mBq/gC in 1990, and became 244 mBq/gC in 2000. This 14 C level in 2000 was still about 7% higher than the pre-bomb level. The decrease in 14 C originated from the past atmospheric nuclear weapons tests could be described by a single exponential function with a half-time of 10.3 years in 1990s. This half-time was shorter than that in the Europe, Canada and the South Pacific. This difference in the decreasing rate between Japan and other countries may be explained by a fact that the amount of CO 2 emission from fossil-fuel combustion continued to increase in Japan in this period. The specific activities of 14 C in wine ethanol determined in this study showed good agreement with those in atmospheric CO 2 predicted by a mathematical model. They were also in the same levels as the 14 C specific activities in atmospheric CO 2 , tree leaves, grass and plant food in Japan and other countries, which were

  3. Correlation between work concentration level and background music: a pilot study.

    Science.gov (United States)

    Shih, Yi-Nuo; Huang, Rong-Hwa; Chiang, Han-Sun

    2009-01-01

    It is a common phenomenon for office workers {to listen to music} while executing daily routines at their desks. The aim of this study was to investigate the correlation between work concentration level and background music. This research would first follow examples in previous researches, and then explore the influence of background music on participants' scores on attention tests. We hope to gain a preliminary understanding of the possible influence of background music on people's focus and concentration when doing work. Thirty-two college students were separated into three controlled groups; all were given the attention test. Group [a] listened to background music while being tested for 10 minutes; group [b] had no background music at all; and group [c] listened to the music for 10 minutes prior to the attention test. The test was conducted in a "noise free" environment. The means and error rates for each group were then calculated. The findings showed that, in comparison with "no music at all", those who listened to music prior to testing obtained higher scores in attentiveness (most probably a supplemental effect of the music), whereas those who listened to music during attention test showed extremely high level of variation in attention test scoring. Background music does affect people's job-site behavior. In fact, all three test conditions - no background music at all, background music before the work shift, and background music during work - have affected worker performance on different levels.

  4. Measurement of the natural radiation background level of Riyadh City

    International Nuclear Information System (INIS)

    Al-Kusayer, T.A.; Al-Haj, A.N.

    1987-01-01

    A gamma spectroscopy system was used to analyze the radionuclides in soil samples and to determine the cumulative radioactivity of terrestrial origin in the Riyadh City area. Minimal work has been done in the 1980s to measure the natural background radiation level in Saudi Arabia by using thermoluminescent dosimeters. The measurement of the natural radioactivity in the Riyadh area for the radionuclide concentration in becquerels per kilogram, the exposure rate arising from radionuclides in grays per hour, and the equivalent dose rate in sieverts per hour are the goals of this work. Soil samples were collected from 21 places in Riyadh City. Each site was sampled for two depth profiles, 0 to 5 cm and 5 to 15 cm. These measurements were taken before the Chernobyl accident, and in the absence of any measurements for that area in the past, this work can be considered in future work for a reference 137 Cs concentration in Riyadh soil to determine the 137 Cs increase in the soil after the Chernobyl accident

  5. Monitoring of external background radiation level in Asa dam ...

    African Journals Online (AJOL)

    An external background ionizing radiation study has been carried out within the Asa Dam Industrial Layout of Ilorin in Kwara State. The study was carried out in 5 stations within the industrial area using two Digilert Nuclear Radiation Monitors. The study has revealed that the external background ionizing radiation is ...

  6. Down syndrome and the high background radiation areas of Kerala

    International Nuclear Information System (INIS)

    Jaikrishan, G.; Ramachandran, E.N.; Karuppasamy, C.V.; Sudheer, K.R.; Andrews, V.J.; Soren, D.C.; Anil Kumar, V.; Koya, P.K.M.; Cheriyan, V.D.; Seshadri, M.

    2010-01-01

    Down syndrome (DS) or trisomy-21 is a complex human clinical entity compromising several functional, structural and developmental features with wide variation in expression levels. The diagnosis is confirmed in majority of the cases by an extra dose of chromosome 21 by cytogenetics and occasionally it may be due to either chromosomal translocation or mosaicism (different cell lines in the same individual). The extra chromosome 21 is usually formed by non-disjunction during meiosis and is the most common numerical chromosomal anomaly compatible with life, as chromosome 21 is one of the smallest with relatively fewer genes most of which are reckoned to be non lethal. Though exact causative factors and pathogenesis is not fully understood, a rise in maternal age at conception coupled with deleterious environmental influence on an ageing ovum is a recognized risk factor. The de novo nature of trisomy-21 and its relatively higher frequency makes it a reliable indicator to assess the role of chronic high background radiation in inducing germ line mutation and congenital malformation. Many other relatively common congenital malformations with multifactorial origin may not have this de novo property and associating its incidence with the prevailing natural background radiation become more complex. In vitro studies have shown association between high intensity radiation and genetics effects but such a relationship so far was not established between DS and radiation

  7. High-level verification

    CERN Document Server

    Lerner, Sorin; Kundu, Sudipta

    2011-01-01

    Given the growing size and heterogeneity of Systems on Chip (SOC), the design process from initial specification to chip fabrication has become increasingly complex. This growing complexity provides incentive for designers to use high-level languages such as C, SystemC, and SystemVerilog for system-level design. While a major goal of these high-level languages is to enable verification at a higher level of abstraction, allowing early exploration of system-level designs, the focus so far for validation purposes has been on traditional testing techniques such as random testing and scenario-based

  8. Health effects in residents of high background radiation regions

    International Nuclear Information System (INIS)

    Hanson, G.P.; Komarov, E.

    1983-01-01

    Studies carried out in various countries and by the World Health Organization on health effects of exposure of populations to high levels of natural background radiation result in observations of different significance. There are indications of changes in chromosome aberration rate; Down's syndrome has been observed to be possibly related to radiation exposure; malignant neoplasms in bone apparently correspond to high concentrations of 226 Ra in drinking water. Although various researchers have looked for them, effects have not been demonstrated regarding cancer mortality (other than malignant neoplasms involving bone), gross congenital abnormalities, fertility index, growth and development, hereditary disease (other than the possibility of Down's syndrome), infant mortality, longevity, multiple births, sex ratio, or spontaneous abortion rate. On the basis of reported data clear quantitative conception of the risk of low-level radiation from natural sources could not be developed and feasibility studies of further epidemiological programmes should be organized. The possibility of reducing the collective population dose from natural sources could be further explored and a basis for necessary legal action on establishment of standards for possible sources of natural radiation, such as building materials, fertilizers, natural gas and water, might be developed. (author)

  9. High potassium level

    Science.gov (United States)

    ... level is very high, or if you have danger signs, such as changes in an ECG . Emergency ... Seifter JL. Potassium disorders. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  10. Cosmic far-infrared background at high galactic latitudes

    International Nuclear Information System (INIS)

    Stecker, F.W.; Puget, J.L.; Fazio, G.G.

    1977-01-01

    We predict far-infrared background fluxes from various cosmic sources. These fluxes lie near the high-frequency side of the blackbody radiation spectrum. These sources could account for a significant fraction of the background radiation at frequencies above 400 GHz which might be misinterpreted as a ''Comptonization'' distortion of the blackbody radiation. Particular attention is paid to the possible contributions from external galaxies, from rich clusters of galaxies, and from galactic dust emission

  11. Cosmic far-infrared background at high galactic latitudes

    International Nuclear Information System (INIS)

    Stecker, F.W.; Puget, J.L.; Fazio, G.G.

    1976-12-01

    Far-infrared background fluxes from various cosmic sources are predicted. These fluxes lie near the high-frequency side of the blackbody radiation spectrum. These sources could account for a significant fraction of the background radiation at frequencies above 400 GHz, which might be misinterpreted as a comptonization distortion of the blackbody radiation. Particular attention is paid to the possible contributions from external galaxies, rich clusters of galaxies and from galactic dust emission

  12. MDT Performance in a High Rate Background Environment

    CERN Document Server

    Aleksa, Martin; Hessey, N P; Riegler, W

    1998-01-01

    A Cs137 gamma source with different lead filters in the SPS beam-line X5 has been used to simulate the ATLAS background radiation. This note shows the impact of high background rates on the MDT efficiency and resolution for three kinds of pulse shaping and compares the results with GARFIELD simulations. Furthermore it explains how the performance can be improved by time slewing corrections and double track separation.

  13. Lateralization of noise bursts in interaurally correlated or uncorrelated background noise using interaural level differences.

    Science.gov (United States)

    Reed, Darrin K; van de Par, Steven

    2015-10-01

    The interaural level difference (ILD) of a lateralized target source may be effectively reduced when the target is presented together with background noise containing zero ILD. It is not certain whether listeners perceive a position congruent with the reduced ILD or the actual target ILD in a lateralization task. Two sets of behavioral experiments revealed that many listeners perceived a position at or even larger than that corresponding to the presented target ILD when a temporal onset/offset asynchrony between the broadband target and the broadband background noise was present. When no temporal asynchrony was present, however, the perceived lateral position indicated a dependency on the coherence of the background noise for several listeners. With interaurally correlated background noise, listeners reported a reduced ILD resulting from the combined target and background noise stimulus. In contrast, several of the listeners made a reasonable estimate of the position corresponding to the target ILD for interaurally uncorrelated, broadband, background noise. No obvious difference in performance was seen between low- or high-frequency stimuli. Extension of a weighting template to the output of a standard equalization-cancellation model was shown to remove a lateral bias on the predicted target ILD resulting from the presence of background noise. Provided that an appropriate weighting template is applied based on knowledge of the background noise coherence, good prediction of the behavioral data is possible.

  14. Position sensitive detection of neutrons in high radiation background field.

    Science.gov (United States)

    Vavrik, D; Jakubek, J; Pospisil, S; Vacik, J

    2014-01-01

    We present the development of a high-resolution position sensitive device for detection of slow neutrons in the environment of extremely high γ and e(-) radiation background. We make use of a planar silicon pixelated (pixel size: 55 × 55 μm(2)) spectroscopic Timepix detector adapted for neutron detection utilizing very thin (10)B converter placed onto detector surface. We demonstrate that electromagnetic radiation background can be discriminated from the neutron signal utilizing the fact that each particle type produces characteristic ionization tracks in the pixelated detector. Particular tracks can be distinguished by their 2D shape (in the detector plane) and spectroscopic response using single event analysis. A Cd sheet served as thermal neutron stopper as well as intensive source of gamma rays and energetic electrons. Highly efficient discrimination was successful even at very low neutron to electromagnetic background ratio about 10(-4).

  15. The phantom menace. Determination of the true Method Detection Limit (MDL) for background levels of PCDDs, PCDFs, and cPCBs in human serum by high-resolution mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Turner, W.; Welch, S.; DiPietro, E.; Cash, T.; McClure, C.; Needham, L.; Patterson, D. [CDC/ATSDR, Atlanta, GA (United States)

    2004-09-15

    The recent worldwide decline in background serum levels of polychlorinated dibenzo-p-dioxins, furans, and coplanar biphenyls (PCDDs/PCDFs/cPCBs) is unquestionably an important finding. However, as serum levels continue to diminish, our analytical methods for measuring these toxicants will continue to be ''pushed to their limit''. In a previous article, we investigated some of the variables that influence the quantification of ''ultra-trace'' (fg/g) concentrations of PCDDs/PCDFs and cPCBs in human serum. In this report, we continue to explore parameters that can affect the determination of the ''true'' detection limit of our method (MDL), using both analytical standards and matrix-based samples.

  16. 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

  17. Beta activity measurements in high, variable gamma backgrounds

    International Nuclear Information System (INIS)

    Stanga, D.; Sandu, E.; Craciun, L.

    1997-01-01

    In many cases beta activity measurements must be performed in high and variable gamma backgrounds. In such instances it is necessary to use well-shielded detectors but this technique is limited to laboratory equipment and frequently insufficient. In order to perform in a simple manner beta activity measurements in high and variable backgrounds a software-aided counting technique have been developed and a counting system have been constructed. This technique combines the different counting techniques with traditional method of successive measurement of the sample and background. The counting system is based on a programmable multi-scaler which is endowed with appropriate software and allow all operations to be performed via keyboard in an interactive fashion. Two large - area proportional detectors were selected in order to have the same background and the same gamma response within 5%. A program has been developed for the counting data analysis and beta activity computing. The software-aided counting technique has been implemented for beta activity measurement in high and variable backgrounds. (authors)

  18. Precise muon drift tube detectors for high background rate conditions

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Albert

    2011-08-04

    The muon spectrometer of the ATLAS-experiment at the Large Hadron Collider consists of drift tube chambers, which provide the precise measurement of trajectories of traversing muons. In order to determine the momentum of the muons with high precision, the measurement of the position of the muon in a single tube has to be more accurate than {sigma}{<=}100 {mu}m. The large cross section of proton-proton-collisions and the high luminosity of the accelerator cause relevant background of neutrons and {gamma}s in the muon spectrometer. During the next decade a luminosity upgrade to 5.10{sup 34} cm{sup -2}s{sup -1} is planned, which will increase the background counting rates considerably. In this context this work deals with the further development of the existing drift chamber technology to provide the required accuracy of the position measurement under high background conditions. Two approaches of improving the drift tube chambers are described: - In regions of moderate background rates a faster and more linear drift gas can provide precise position measurement without changing the existing hardware. - At very high background rates drift tube chambers consisting of tubes with a diameter of 15 mm are a valuable candidate to substitute the CSC muon chambers. The single tube resolution of the gas mixture Ar:CO{sub 2}:N{sub 2} in the ratio of 96:3:1 Vol %, which is more linear and faster as the currently used drift gas Ar:CO{sub 2} in the ratio of 97:3 Vol %, was determined at the Cosmic Ray Measurement Facility at Garching and at high {gamma}-background counting rates at the Gamma Irradiation Facility at CERN. The alternative gas mixture shows similar resolution without background. At high background counting rates it shows better resolution as the standard gas. To analyse the data the various parts of the setup have to be aligned precisely to each other. The change to an alternative gas mixture allows the use of the existing hardware. The second approach are drift tubes

  19. General Algorithm (High level)

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. General Algorithm (High level). Iteratively. Use Tightness Property to remove points of P1,..,Pi. Use random sampling to get a Random Sample (of enough points) from the next largest cluster, Pi+1. Use the Random Sampling Procedure to approximate ci+1 using the ...

  20. Radioactivity in the groundwater of a high background radiation area.

    Science.gov (United States)

    Shabana, E I; Kinsara, A A

    2014-11-01

    Natural radioactivity was measured in groundwater samples collected from 37 wells scattered in an inhabited area of high natural background radiation, in a purpose of radiation protection. The study area is adjacent to Aja heights of granitic composition in Hail province, Saudi Arabia. Initial screening for gross α and gross β activities showed levels exceeded the national regulation limits set out for gross α and gross β activities in drinking water. The gross α activity ranged from 0.17 to 5.41 Bq L(-)(1) with an average value of 2.15 Bq L(-)(1), whereas gross β activity ranged from 0.48 to 5.16 Bq L(-)(1), with an average value of 2.60 Bq L(-)(1). The detail analyses indicated that the groundwater of this province is contaminated with uranium and radium ((226)Ra and (228)Ra). The average activity concentrations of (238)U, (234)U, (226)Ra and (228)Ra were 0.40, 0.77, 0.29 and 0.46 Bq L(-)(1), respectively. The higher uranium content was found in the samples of granitic aquifers, whereas the higher radium content was found in the samples of sandstone aquifers. Based on the obtained results, mechanism of leaching of the predominant radionuclides has been discussed in detail. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Low-level radioactive waste management. Background paper

    International Nuclear Information System (INIS)

    Fawcett, R.

    1993-11-01

    The management of radioactive waste is one of the most serious environmental problems facing Canadians. From the early industrial uses of radioactive material in the 1930s to the development of nuclear power reactors and the medical and experimental use of radioisotopes today, there has been a steady accumulation of waste products. Although the difficulties involved in radioactive waste management are considerable, responsible solutions are possible. This paper will discuss low-level radioactive waste, including its production, the amounts in storage, the rate of waste accumulation and possible strategies for its management. (author). 2 figs

  2. Precise muon drift tube detectors for high background rate conditions

    CERN Document Server

    Engl, Albert; Dünnweber, Wolfgang

    The muon spectrometer of the ATLAS-experiment at the Large H adron Collider consists of drift tube chambers, which provide the precise m easurement of trajec- tories of traversing muons. In order to determine the moment um of the muons with high precision, the measurement of the position of the m uon in a single tube has to be more accurate than σ ≤ 100 m. The large cross section of proton-proton-collisions and th e high luminosity of the accelerator cause relevant background of neutrons and γ s in the muon spectrome- ter. During the next decade a luminosity upgrade [1] to 5 10 34 cm − 2 s − 1 is planned, which will increase the background counting rates consider ably. In this context this work deals with the further development of the existing drift chamber tech- nology to provide the required accuracy of the position meas urement under high background conditions. Two approaches of improving the dri ft tube chambers are described: • In regions of moderate background rates a faster and more lin ear ...

  3. Effect of background noise on neuronal coding of interaural level difference cues in rat inferior colliculus.

    Science.gov (United States)

    Mokri, Yasamin; Worland, Kate; Ford, Mark; Rajan, Ramesh

    2015-07-01

    Humans can accurately localize sounds even in unfavourable signal-to-noise conditions. To investigate the neural mechanisms underlying this, we studied the effect of background wide-band noise on neural sensitivity to variations in interaural level difference (ILD), the predominant cue for sound localization in azimuth for high-frequency sounds, at the characteristic frequency of cells in rat inferior colliculus (IC). Binaural noise at high levels generally resulted in suppression of responses (55.8%), but at lower levels resulted in enhancement (34.8%) as well as suppression (30.3%). When recording conditions permitted, we then examined if any binaural noise effects were related to selective noise effects at each of the two ears, which we interpreted in light of well-known differences in input type (excitation and inhibition) from each ear shaping particular forms of ILD sensitivity in the IC. At high signal-to-noise ratios (SNR), in most ILD functions (41%), the effect of background noise appeared to be due to effects on inputs from both ears, while for a large percentage (35.8%) appeared to be accounted for by effects on excitatory input. However, as SNR decreased, change in excitation became the dominant contributor to the change due to binaural background noise (63.6%). These novel findings shed light on the IC neural mechanisms for sound localization in the presence of continuous background noise. They also suggest that some effects of background noise on encoding of sound location reported to be emergent in upstream auditory areas can also be observed at the level of the midbrain. © 2015 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  4. High level nuclear wastes

    International Nuclear Information System (INIS)

    Lopez Perez, B.

    1987-01-01

    The transformations involved in the nuclear fuels during the burn-up at the power nuclear reactors for burn-up levels of 33.000 MWd/th are considered. Graphs and data on the radioactivity variation with the cooling time and heat power of the irradiated fuel are presented. Likewise, the cycle of the fuel in light water reactors is presented and the alternatives for the nuclear waste management are discussed. A brief description of the management of the spent fuel as a high level nuclear waste is shown, explaining the reprocessing and giving data about the fission products and their radioactivities, which must be considered on the vitrification processes. On the final storage of the nuclear waste into depth geological burials, both alternatives are coincident. The countries supporting the reprocessing are indicated and the Spanish programm defined in the Plan Energetico Nacional (PEN) is shortly reviewed. (author) 8 figs., 4 tabs

  5. ALICE High Level Trigger

    CERN Multimedia

    Alt, T

    2013-01-01

    The ALICE High Level Trigger (HLT) is a computing farm designed and build for the real-time, online processing of the raw data produced by the ALICE detectors. Events are fully reconstructed from the raw data, analyzed and compressed. The analysis summary together with the compressed data and a trigger decision is sent to the DAQ. In addition the reconstruction of the events allows for on-line monitoring of physical observables and this information is provided to the Data Quality Monitor (DQM). The HLT can process event rates of up to 2 kHz for proton-proton and 200 Hz for Pb-Pb central collisions.

  6. Below background levels of blood lead impact cytokine levels in male and female mice

    International Nuclear Information System (INIS)

    Iavicoli, I.; Carelli, G.; Stanek, E.J.; Castellino, N.; Calabrese, E.J.

    2006-01-01

    A number of studies have documented that Pb exerts immunotoxic effects on T lymphocytes. In studies designed to explore this general response over a broad dose range, female Swiss mice were administered six different diets containing Pb acetate 1 day after mating. During lactation, the mothers received the same feed given during pregnancy, and the same diets were administered to the offspring for 9 months after weaning. At the end of exposure, blood Pb level in the offspring was determined, and possible changes in two type 1 cytokines (IL-2, INF-γ) and one type 2 cytokine (IL-4) in the serum were measured. At higher dietary Pb levels (40 and 400 ppm), a significant increase in IL-4 production was associated with a profound decrease in INF-γ and IL-2 production. At the lowest Pb diet level (0.02 ppm), which resulted in a blood lead level of (0.8 μg/dL), which is below background (2-3 μg/dL) values in humans, increases in INF-γ and IL-2 production along with a significant decrease in IL-4 production were observed. The findings provide evidence of a reversal of lead-induced cytokine skewing depending on the blood lead concentration. As blood lead concentration increases, there is a notable skewing toward Th2, while the pattern is reversed favoring Th1 development at lower blood lead values. The present findings are also notable since they indicate the potential for dietary Pb to have significant biological effects below normal background concentrations

  7. Attempt to measure the cosmic background radiation at high altitude

    International Nuclear Information System (INIS)

    Labeyrie, Jacques; Le Boiteux, Henri

    1959-01-01

    Results are given of the measurement by G.M. tubes of hard component of cosmic background between o and 60 km of altitude, at 43 deg. N latitude, on january 27, 1959 (17 h. GMT). The counting rate starts at 0.3 pulses per second (sea level) reaches a maximum value of 15.6 (18 km) and remains constant at 5.7 above 40 km. Reprint of a paper published in Le Journal de Physique et le Radium, t. 20, p. 573, may 1959

  8. Background level of natural radioactivities in a giant water Cherenkov detector and its surrounding environment

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Sakanoue, Masanobu; Komura, Kazuhisa; Ueno, Kaoru

    1989-01-01

    The KAMIOKANDE-II water Cherenkov detector for the measurement of nucleon decay and/or solar neutrino has been operating in the underground laboratory at a depth of 2,700 m.w.e. (meter water equivalent) in Kamioka mine of Gifu Prefecture. Concentrations of 238 U, 232 Th, 226 Ra and 222 Rn as the major background sources have been measured for various kinds of rocks, mine water, mine air and high purity water used as a detector during the period from August 1986 to December 1987. The concentration levels of these radionuclides and their seasonal variation have become clear. Some of these results have provided useful informations for decreasing the background level of water Cherenkov detector. (author)

  9. High-Energy Neutron Backgrounds for Underground Dark Matter Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu [Syracuse Univ., NY (United States)

    2016-01-01

    Direct dark matter detection experiments usually have excellent capability to distinguish nuclear recoils, expected interactions with Weakly Interacting Massive Particle (WIMP) dark matter, and electronic recoils, so that they can efficiently reject background events such as gamma-rays and charged particles. However, both WIMPs and neutrons can induce nuclear recoils. Neutrons are then the most crucial background for direct dark matter detection. It is important to understand and account for all sources of neutron backgrounds when claiming a discovery of dark matter detection or reporting limits on the WIMP-nucleon cross section. One type of neutron background that is not well understood is the cosmogenic neutrons from muons interacting with the underground cavern rock and materials surrounding a dark matter detector. The Neutron Multiplicity Meter (NMM) is a water Cherenkov detector capable of measuring the cosmogenic neutron flux at the Soudan Underground Laboratory, which has an overburden of 2090 meters water equivalent. The NMM consists of two 2.2-tonne gadolinium-doped water tanks situated atop a 20-tonne lead target. It detects a high-energy (>~ 50 MeV) neutron via moderation and capture of the multiple secondary neutrons released when the former interacts in the lead target. The multiplicity of secondary neutrons for the high-energy neutron provides a benchmark for comparison to the current Monte Carlo predictions. Combining with the Monte Carlo simulation, the muon-induced high-energy neutron flux above 50 MeV is measured to be (1.3 ± 0.2) ~ 10-9 cm-2s-1, in reasonable agreement with the model prediction. The measured multiplicity spectrum agrees well with that of Monte Carlo simulation for multiplicity below 10, but shows an excess of approximately a factor of three over Monte Carlo prediction for multiplicities ~ 10 - 20. In an effort to reduce neutron backgrounds for the dark matter experiment SuperCDMS SNO- LAB, an active neutron veto was developed

  10. On the frequency dependence of the high temperature background

    International Nuclear Information System (INIS)

    Povolo, F.; Hermida, E.B.

    1996-01-01

    The high temperature background (HTB) damping in metals and alloys has been measured mostly as a function of temperature. These data were described by several empirical expressions proposed in the literature. In the present work, HTB in pure Mg and in two alloys (Zry-4 and Cu-5 at.%Au), measured with a torsion pendulum with variable moment of inertia, are analyzed on considering a new treatment of the data. This analysis provides an useful tool to determine whether a damping process is linear or not. (orig.)

  11. Past and present views in the approach to the problem of high natural background areas

    International Nuclear Information System (INIS)

    Mastino, G.G.

    1982-01-01

    High natural background areas are of great interest because they present anomalous conditions in their geological and geochemical features and consequently in the background radiation levels. High natural background areas have been recognised as representing a valid field of investigation for assessing the effects induced by low-level exposures. Such an approach represents the first attempt to draw an environmental impact evaluation, even if focussed on a single potentially harmful parameter only. Past and current studies on High Background Radiation Areas are reviewed with special emphasis on the ongoing programs and prospectives; their significance is discussed on the basis of the sectorial approach mostly used in the environmental studies. A more complete approach is suggested based on the impact evaluation and extention to all the potentially harmful environmental factors

  12. Secondary particle in background levels and effects on detectors at future hadron colliders

    International Nuclear Information System (INIS)

    Pal, T.

    1993-06-01

    The next generation of hadron colliders, the Superconducting Super Collider (SSC) and the Large Hadron Collider (LHC), will operate at high center-of-mass energies and luminosities. Namely, for the SSC (LHC) √s = 40 TeV (√s = 16 TeV) and L = 10 33 cm -2 s -1 (L = 3 x 10 34 cm -2 s -1 ). These conditions will result in the production of large backgrounds as well as radiation environments. Ascertaining the backgrounds, in terms of the production of secondary charged and neutral particles, and the radiation environments are important considerations for the detectors proposed for these colliders. An initial investigation of the radiation levels in the SSC detectors was undertaken by D. Groom and colleagues, in the context of the ''task force on radiation levels in the SSC interaction regions.'' The method consisted essentially of an analytic approach, using standard descriptions of average events in conjunction with simulations of secondary processes. Following Groom's work, extensive Monte Carlo simulations were performed to address the issues of backgrounds and radiation environments for the GEM and SD C3 experiments proposed at the SSC, and for the ATLAS and CMS experiments planned for the LHC. The purpose of the present article is to give a brief summary of some aspects of the methods, assumptions, and calculations performed to date (principally for the SSC detectors), and to stress the relevance of such calculations to the detectors proposed for the study of B-physics in particular

  13. Microbiology of the surface water samples in the high background radiation areas of Ramsar, Iran

    International Nuclear Information System (INIS)

    Motamedifar, Mohammad; Zamani, Khosrow; Sedigh, Hadi; Mortazavi, Seyed Mohammad Javad; Taeb, Shahram; Haghani, M.; Mortazavi, Seyed Ali Reza; Soofi, Amir

    2014-01-01

    Residents of high background radiation areas of Ramsar have lived in these areas for many generations and received radiation doses much higher than the dose limit recommended by ICRP for radiation workers. The radioactivity of the high background radiation areas of Ramsar is reported to be due to 226 Ra and its decay products, which have been brought to the surface by the waters of hot springs. Over the past years the department has focused on different aspects of the health effects of the elevated levels of natural radiation in Ramsar. This study was aimed to perform a preliminary investigation on the bioeffects of exposure to elevated levels of natural radiation on the microbiology of surface water samples. Water samples were collected from surface water streams in Talesh Mahalleh district, Ramsar as well as a nearby area with normal levels of background radiation. Only two strains of bacteria, that is, Providencia stuartii and Shimwellia blattae, could be isolated from the water samples collected from high background radiation areas, while seven strains (Escherichia coli, Enterobacter asburiae, Klebsiella pneumoniae, Shigella dysenteriae, Buttiauxella agerstis, Tatumella punctuata and Raoultella ornithinolytica) were isolated from the water samples collected from normal background radiation areas. All the bacteria isolated from water samples of high and normal background radiation areas were sensitive to ultraviolet radiation, heat, betadine, alcohol, and deconex. Although other investigators have reported that bacteria isolated from hot springs show radioresistance, the results reported here do not reveal any adaptive response. (author)

  14. Calculating background levels for ecological risk parameters in toxic harbor sediment

    Science.gov (United States)

    Leadon, C.J.; McDonnell, T.R.; Lear, J.; Barclift, D.

    2007-01-01

    Establishing background levels for biological parameters is necessary in assessing the ecological risks from harbor sediment contaminated with toxic chemicals. For chemicals in sediment, the term contaminated is defined as having concentrations above background and significant human health or ecological risk levels. For biological parameters, a site could be considered contaminated if levels of the parameter are either more or less than the background level, depending on the specific parameter. Biological parameters can include tissue chemical concentrations in ecological receptors, bioassay responses, bioaccumulation levels, and benthic community metrics. Chemical parameters can include sediment concentrations of a variety of potentially toxic chemicals. Indirectly, contaminated harbor sediment can impact shellfish, fish, birds, and marine mammals, and human populations. This paper summarizes the methods used to define background levels for chemical and biological parameters from a survey of ecological risk investigations of marine harbor sediment at California Navy bases. Background levels for regional biological indices used to quantify ecological risks for benthic communities are also described. Generally, background stations are positioned in relatively clean areas exhibiting the same physical and general chemical characteristics as nearby areas with contaminated harbor sediment. The number of background stations and the number of sample replicates per background station depend on the statistical design of the sediment ecological risk investigation, developed through the data quality objective (DQO) process. Biological data from the background stations can be compared to data from a contaminated site by using minimum or maximum background levels or comparative statistics. In Navy ecological risk assessments (ERA's), calculated background levels and appropriate ecological risk screening criteria are used to identify sampling stations and sites with contaminated

  15. Database on epidemiological survey in high background radiation research

    International Nuclear Information System (INIS)

    Zhou Sunyuan; Guo Furong; Liu Yusheng

    1992-01-01

    In order to store and check the data of the health survey in high background radiation area (HBRA) and control area in Guangdong Province, and to use these data in future, three databases were set up by using RBASE 5000 database software. (1) HD: the database based on the household registers especially established for the health survey from 1979 to 1986, covering more than 160000 subjects and 2200000 data. (2) DC: the database based on the registration cards of deaths from cancers and all other diseases during the period of 1975-1986 including more than 10000 cases and 260000 data. (3) MCC: the database for the case-control study on mutation-related factors for four kinds of cancers (liver, stomach, lung cancers and leukemia), embracing 626 subjects and close to 90000 data. The data in the databases were checked up with the original records and compared with the manual analytical results

  16. High blood cholesterol levels

    Science.gov (United States)

    Cholesterol - high; Lipid disorders; Hyperlipoproteinemia; Hyperlipidemia; Dyslipidemia; Hypercholesterolemia ... There are many types of cholesterol. The ones talked about most are: ... lipoprotein (HDL) cholesterol -- often called "good" cholesterol ...

  17. Health effects in residents of high background radiation regions

    International Nuclear Information System (INIS)

    Hanson, G.P.

    1984-01-01

    Although the health effects of radiation doses in occupationally exposed persons had received attention, it was not until the 1950s, when the atmospheric atom bomb tests of the United States and the Soviet Union had raised the level of environmental radioactivity, that the long-term effects of low-level radiation dosage became a matter of popular concern throughout the world. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was created, and the World Health Organization (WHO) appointed an expert committee to provide advice concerning radiation and human health. In its first report, the WHO expert committee identified several areas of high natural radiation where studies of the exposed population might possibly provide information concerning the effects of chromic low-level radiation dosage

  18. Peculiar velocity effects in high-resolution microwave background experiments

    International Nuclear Information System (INIS)

    Challinor, Anthony; Leeuwen, Floor van

    2002-01-01

    We investigate the impact of peculiar velocity effects due to the motion of the solar system relative to the cosmic microwave background (CMB) on high resolution CMB experiments. It is well known that on the largest angular scales the combined effects of Doppler shifts and aberration are important; the lowest Legendre multipoles of total intensity receive power from the large CMB monopole in transforming from the CMB frame. On small angular scales aberration dominates and is shown here to lead to significant distortions of the total intensity and polarization multipoles in transforming from the rest frame of the CMB to the frame of the solar system. We provide convenient analytic results for the distortions as series expansions in the relative velocity of the two frames, but at the highest resolutions a numerical quadrature is required. Although many of the high resolution multipoles themselves are severely distorted by the frame transformations, we show that their statistical properties distort by only an insignificant amount. Therefore, the cosmological parameter estimation is insensitive to the transformation from the CMB frame (where theoretical predictions are calculated) to the rest frame of the experiment

  19. Background field coils for the High Field Test Facility

    International Nuclear Information System (INIS)

    Zbasnik, J.P.; Cornish, D.N.; Scanlan, R.M.; Jewell, A.M.; Leber, R.L.; Rosdahl, A.R.; Chaplin, M.R.

    1980-01-01

    The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb 3 Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is designed to be parted along the midplane to allow high-field conductors, under development for Tokamak fusion machines, to be inserted and tested. The background field coils were wound pancake-fashion, with cold-welded joints at both the inner and outer diameters. Turn-to-turn insulation was fabricated at LLNL from epoxy-fiberglass strip. The coils were assembled and tested in our 2-m-diam cryostat to verify their operation

  20. Parental background, early scholastic ability, the allocation into secondary school tracks and language skills at the age of 15 years in a highly differentiated system: a test of the contradictions between a two- or three-level approach

    NARCIS (Netherlands)

    Dronkers, J.

    2014-01-01

    Recently Dunne (2010) and Dronkers, van der Velden & Dunne (2011) introduced a three-level model: countries, schools, and students. They showed that school characteristics like socioeconomic composition and ethnic diversity have substantial effects on achievement levels and also affect the relation

  1. High-resolution subgrid models: background, grid generation, and implementation

    Science.gov (United States)

    Sehili, Aissa; Lang, Günther; Lippert, Christoph

    2014-04-01

    The basic idea of subgrid models is the use of available high-resolution bathymetric data at subgrid level in computations that are performed on relatively coarse grids allowing large time steps. For that purpose, an algorithm that correctly represents the precise mass balance in regions where wetting and drying occur was derived by Casulli (Int J Numer Method Fluids 60:391-408, 2009) and Casulli and Stelling (Int J Numer Method Fluids 67:441-449, 2010). Computational grid cells are permitted to be wet, partially wet, or dry, and no drying threshold is needed. Based on the subgrid technique, practical applications involving various scenarios were implemented including an operational forecast model for water level, salinity, and temperature of the Elbe Estuary in Germany. The grid generation procedure allows a detailed boundary fitting at subgrid level. The computational grid is made of flow-aligned quadrilaterals including few triangles where necessary. User-defined grid subdivision at subgrid level allows a correct representation of the volume up to measurement accuracy. Bottom friction requires a particular treatment. Based on the conveyance approach, an appropriate empirical correction was worked out. The aforementioned features make the subgrid technique very efficient, robust, and accurate. Comparison of predicted water levels with the comparatively highly resolved classical unstructured grid model shows very good agreement. The speedup in computational performance due to the use of the subgrid technique is about a factor of 20. A typical daily forecast can be carried out in less than 10 min on a standard PC-like hardware. The subgrid technique is therefore a promising framework to perform accurate temporal and spatial large-scale simulations of coastal and estuarine flow and transport processes at low computational cost.

  2. How important is cultural background for the level of intergenerational mobility?

    DEFF Research Database (Denmark)

    Schnitzlein, Daniel D.

    Using results on brother correlations in permanent earnings for different groups of second generation immigrants based on administrative data from Denmark, this letter analyzes the role of cultural background in the determination of the level of intergenerational mobility. The results indicate th...... that cultural background is not a major determinant of the level of intergenerational economic mobility.......Using results on brother correlations in permanent earnings for different groups of second generation immigrants based on administrative data from Denmark, this letter analyzes the role of cultural background in the determination of the level of intergenerational mobility. The results indicate...

  3. Sister chromatid exchanges (SCEs) in lymphocytes of inhabitants in high background radiation area

    International Nuclear Information System (INIS)

    Li Jinsheng; Zheng Qiaoling

    1985-01-01

    Blood samples were taken from 126 students of 15-16 years old, living in the high background radiation area, and from 124 controls of the same age range, living in the normal background radiation area. All students were interviewed for evaluation of their health status. Whole blood cultures were done with RPMI 1640 medium supplemented with 20% fetal calf serum and antibiotics, The culture were incubated for 54-56 h in the presence of BrdU (10 μg/ml). Metaphases were stained for SCE using a modified techniqu of perry and Wolff. From each person 20 second division metaphases were analysed for SCEs. The average frequencies of SCEs observed in the high background group and the control group are presented. More SCEs were observed in the high background group than in the control with a statistically signigicant difference. In regard to the sex factor, it was found that the SCE frequencies in both sexes of the high background group were slightly higher than those in the control group. These findings suggest that continuous low-level irradiation by the high background radiation may induce increased frequency of SCEs

  4. Secondary particle background levels and effects on detectors at future hadron colliders

    International Nuclear Information System (INIS)

    Pal, T.

    1993-01-01

    The next generation of hadron colliders, the Superconducting Super Collider (SSC) and the Large Hadron Collider (LHC), will operate at high center-of-mass energies and luminosities. Namely, for the SSC(LHC) √s=40TeV (√s=16TeV) and L=10 33 cm -2 s -1 (L=3x10 34 cm -2 s -1 ). These conditions will result in the production of large backgrounds as well as radiation environments. Ascertaining the backgrounds, in terms of the production of secondary charged and neutral particles, and the radiation environments are important considerations for the detectors proposed for these colliders. An initial investigation of the radiation levels in the SSC detectors was undertaken by D. Groom and colleagues, in the context of the open-quotes task force on radiation levels in the SSC interaction regions.close quotes The method consisted essentially of an analytic approach, using standard descriptions of average events in conjunction with simulations of secondary processes

  5. Comparison of selection methods to deduce natural background levels for groundwater units

    NARCIS (Netherlands)

    Griffioen, J.; Passier, H.F.; Klein, J.

    2008-01-01

    Establishment of natural background levels (NBL) for groundwater is commonly performed to serve as reference when assessing the contamination status of groundwater units. We compare various selection methods to establish NBLs using groundwater quality data forfour hydrogeologically different areas

  6. Estimation of background noise level on seismic station using statistical analysis for improved analysis accuracy

    Science.gov (United States)

    Han, S. M.; Hahm, I.

    2015-12-01

    We evaluated the background noise level of seismic stations in order to collect the observation data of high quality and produce accurate seismic information. Determining of the background noise level was used PSD (Power Spectral Density) method by McNamara and Buland (2004) in this study. This method that used long-term data is influenced by not only innate electronic noise of sensor and a pulse wave resulting from stabilizing but also missing data and controlled by the specified frequency which is affected by the irregular signals without site characteristics. It is hard and inefficient to implement process that filters out the abnormal signal within the automated system. To solve these problems, we devised a method for extracting the data which normally distributed with 90 to 99% confidence intervals at each period. The availability of the method was verified using 62-seismic stations with broadband and short-period sensors operated by the KMA (Korea Meteorological Administration). Evaluation standards were NHNM (New High Noise Model) and NLNM (New Low Noise Model) published by the USGS (United States Geological Survey). It was designed based on the western United States. However, Korean Peninsula surrounded by the ocean on three sides has a complicated geological structure and a high population density. So, we re-designed an appropriate model in Korean peninsula by statistically combined result. The important feature is that secondary-microseism peak appeared at a higher frequency band. Acknowledgements: This research was carried out as a part of "Research for the Meteorological and Earthquake Observation Technology and Its Application" supported by the 2015 National Institute of Meteorological Research (NIMR) in the Korea Meteorological Administration.

  7. Background problem for a large solid angle, high sensitivity detector

    International Nuclear Information System (INIS)

    Chen, M.

    1977-01-01

    With extremely good vacuum (10 -11 to 10 -13 torr) and well controlled beams, the ISR has a good reputation for clean beam conditions and low background for most types of experiments. However, for a detector covering a large solid angle, measuring processes with small cross sections (approximately 10 -38 cm 2 ) there are serious background problems which took almost a year to solve. Since ISABELLE may have similar problems, a summary is given of experience at the ISR with the hope that some of the solutions can be installed in ISABELLE at an early stage

  8. Nature of the Background Ultraviolet Radiation Field at High Redshifts

    Indian Academy of Sciences (India)

    tribpo

    J. Astrophys. Astr. (2000) 21, 19-27 .... to know the shape of the ionizing radiation to determine the ionization parameter from the C II to C IV ratio. ... different shapes of the background radiation spectrum as explained in the text. The solid lines.

  9. Thyroid nodularity and chromosome aberrations among women in areas of high background radiation in China

    International Nuclear Information System (INIS)

    Wang, Z.Y.; Boice, J.D. Jr.; Wei, L.X.; Beebe, G.W.; Zha, Y.R.; Kaplan, M.M.; Tao, Z.F.; Maxon, H.R. III; Zhang, S.Z.; Schneider, A.B.

    1990-01-01

    Thyroid nodularity following continuous low-dose radiation exposure in China was determined in 1,001 women aged 50-65 years who resided in areas of high background radiation (330 mR/yr) their entire lives, and in 1,005 comparison subjects exposed to normal levels of radiation (114 mR/yr). Cumulative doses to the thyroid were estimated to be of the order of 14 cGy and 5 cGy, respectively. Personal interviews and physical examinations were conducted, and measurements were made of serum thyroid hormone levels, urinary iodine concentrations, and chromosome aberrations in circulating lymphocytes. For all nodular disease, the prevalences in the high background and control areas were 9.5% and 9.3%, respectively. For single nodules, the prevalences were 7.4% in the high background area and 6.6% in the control area (prevalence ratio = 1.13; 95% confidence interval = 0.82-1.55). There were no differences found in serum levels of thyroid hormones. Women in the high background region, however, had significantly lower concentrations of urinary iodine and significantly higher frequencies of stable and unstable chromosome aberrations. Increased intake of allium vegetables such as garlic and onions was associated with a decreased risk of nodular disease, which seems consistent with experimental studies suggesting that allium compounds can inhibit tumor growth and proliferation. The prevalence of mild diffuse goiter was higher in the high background radiation region, perhaps related to a low dietary intake of iodine. These data suggest that continuous exposure to low-level radiation throughout life is unlikely to appreciably increase the risk of thyroid cancer. However, such exposure may cause chromosomal damage

  10. Traffic background level and signal duration effects on aircraft noise judgment

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, G W; Haasz, A A

    1977-04-22

    The effects of background traffic noise level and signal duration on perceived aircraft noise levels during a flyover event are investigated. Tapes of traffic noise at different levels on which aircraft flyover noise events of different durations were superimposed were played to groups of observers in a room simulating indoor conditions. It is found that the presence of steady background traffic noise reduces the perceived noisiness of aircraft flyovers provided that the duration of the flyover event is sufficiently short in relation to flyover time. For a given event level, a reduction of 21 dB(A) in background noise level leads to the perception of a 5.5 dB(A) increase in peak event level. Regressions of observer response with the noise pollution index show a lower correlation than those with variables based on background noise level and peak signal level, although the data are found to exhibit a number of significant trends associated with noise pollution index variations.

  11. Comparison of norovirus RNA levels in outbreak-related oysters with background environmental levels.

    Science.gov (United States)

    Lowther, James A; Gustar, Nicole E; Hartnell, Rachel E; Lees, David N

    2012-02-01

    Norovirus is the principal agent of bivalve shellfish-associated gastroenteric illness worldwide. Numerous studies using PCR have demonstrated norovirus contamination in a significant proportion of both oyster and other bivalve shellfish production areas and ready-to-eat products. By comparison, the number of epidemiologically confirmed shellfish-associated outbreaks is relatively low. This suggests that factors other than the simple presence or absence of virus RNA are important contributors to the amount of illness reported. This study compares norovirus RNA levels in oyster samples strongly linked to norovirus or norovirus-type illness with the levels typically found in commercial production areas (non-outbreak-related samples). A statistically significant difference between norovirus levels in the two sets of samples was observed. The geometric mean of the levels in outbreak samples (1,048 copies per g) was almost one order of magnitude higher than for positive non-outbreak-related samples (121 copies per g). Further, while none of the outbreak-related samples contained fewer than 152 copies per g, the majority of positive results for non-outbreak-related samples was below this level. These observations support the concept of a dose-response for norovirus RNA levels in shellfish and could help inform the establishment of threshold criteria for risk management.

  12. Ground Level Ozone Regional Background Characteristics In North-west Pacific Rim

    Science.gov (United States)

    Chiang, C.; Fan, J.; Chang, J. S.

    2007-12-01

    Understanding the ground level ozone regional background characteristics is essential in understanding the contribution of long-range transport of pollutants from Asia Mainland to air quality in downwind areas. In order to understand this characteristic in north-west Pacific Rim, we conducted a coupled study using ozone observation from regional background stations and 3-D regional-scale chemical transport model simulations. We used O3, CO, wind speed and wind direction data from two regional background stations and ¡§other stations¡¨ over a ten year period and organized several numerical experiments to simulate one spring month in 2003 to obtain a deeper understanding. The so called ¡§other stations¡¨ had actually been named as background stations under various governmental auspices. But we found them to be often under strong influence of local pollution sources with strong diurnal or slightly longer time variations. We found that the Yonagunijima station (24.74 N, 123.02 E) and Heng-Chuen station (21.96 N,120.78 E), about a distance of 400 km apart, have almost the same ozone time series pattern. For these two stations in 2003, correlation coefficients (R2) for annual observed ozone concentration is about 0.64, in the springtime it is about 0.7, and in a one-month period at simulation days it is about 0.76. These two stations have very little small scale variations in all the variables studied. All variations are associated with large scale circulation changes. This is especially so at Yonagunijima station. Using a 3-D regional-scale chemical transport model for East Asia region including contribution from Asia continental outflow and neighboring island pollution areas we found that the Yonagunijima and HengChuen station are indeed free of pollutants from all neighboring areas keeping in mind that pollutants from Taiwan area is never far away. Ozone concentrations in these two stations are dominated by synoptic scale weather patterns, with diffused

  13. Background Noise Analysis in a Few-Photon-Level Qubit Memory

    Science.gov (United States)

    Mittiga, Thomas; Kupchak, Connor; Jordaan, Bertus; Namazi, Mehdi; Nolleke, Christian; Figeroa, Eden

    2014-05-01

    We have developed an Electromagnetically Induced Transparency based polarization qubit memory. The device is composed of a dual-rail probe field polarization setup colinear with an intense control field to store and retrieve any arbitrary polarization state by addressing a Λ-type energy level scheme in a 87Rb vapor cell. To achieve a signal-to-background ratio at the few photon level sufficient for polarization tomography of the retrieved state, the intense control field is filtered out through an etalon filtrating system. We have developed an analytical model predicting the influence of the signal-to-background ratio on the fidelities and compared it to experimental data. Experimentally measured global fidelities have been found to follow closely the theoretical prediction as signal-to-background decreases. These results suggest the plausibility of employing room temperature memories to store photonic qubits at the single photon level and for future applications in long distance quantum communication schemes.

  14. Measurement of speech levels in the presence of time varying background noise

    Science.gov (United States)

    Pearsons, K. S.; Horonjeff, R.

    1982-01-01

    Short-term speech level measurements which could be used to note changes in vocal effort in a time varying noise environment were studied. Knowing the changes in speech level would in turn allow prediction of intelligibility in the presence of aircraft flyover noise. Tests indicated that it is possible to use two second samples of speech to estimate long term root mean square speech levels. Other tests were also performed in which people read out loud during aircraft flyover noise. Results of these tests indicate that people do indeed raise their voice during flyovers at a rate of about 3-1/2 dB for each 10 dB increase in background level. This finding is in agreement with other tests of speech levels in the presence of steady state background noise.

  15. Distribution characteristics of natural gamma background levels around the capital city Shillong, Meghalaya (India)

    International Nuclear Information System (INIS)

    Kukreti, B.M.; Sharma, G.K.; Rao, M.S.; Ramabhadraih, T.; Bhaskar Rao, Arjun; Bhuphang, A.

    2012-01-01

    Onsite measurement of natural gamma radiation around the capital city Shillong in Meghalaya, has been carried out using GPS device and environmental survey meter. Each referenced insitu data point was validated at the site by means of simultaneous measurements of radiation levels (at 1.0 mts height) through handheld dosimeters. Collected data points on natural background levels, have been analysed and quantified in the context of preparing reference background levels in the city in order to deal with any radiological emergency that may arise in the public domain. Study reveals Gaussian distributed mean annual gamma dose of 0.77 mSv (n=53) in the range of 0.38 to 1.51 mSv. The study area, bound by the coordinates N (25.50°-25.66°, and E (91.82°-91.96°) indicates few pockets of higher average background levels, particularly towards the eastern side of study area, namely Nongmynsong, NEIGRIMS and Happy Valley. However, from the radiological safety aspects in public domain, all these reported levels are within the safety limits of prevailing environmental background. (author)

  16. Cancer occurrence in the high natural background radiation area of Kerala coast

    International Nuclear Information System (INIS)

    Krishnan Nair, M.; Sreedevi Amma, N.; Ramachandran, T.P.; Varghese Cherian; Jayalakshmy, P.; Mani, K.S.; Boban, T.G.; Jayadevan, S.; Gangadharan, P.

    1994-01-01

    In order to assess the health effects if any, in populations living in high background radiation areas, the Department of Atomic Energy has sanctioned a 5-year project to establish a Registry covering Karunagappally taluk. The study proposes to cover a population of about 1,00,000 persons living in high background radiation areas where the radiation levels range anywhere between 10 and 825 μR/h inside the houses; for comparison the study proposes to cover another 3,00,000 persons living in nearby normal areas where the natural radiation levels range between 6 and 200 μ R/h. The data collected so far in the first 2.5 years are presented in this paper which covers a population of about 1,10,000 persons living in three villages. No attempt is made to interpret the data at this preliminary stage. (author). 7 tabs

  17. THE HIGH BACKGROUND RADIATION AREA IN RAMSAR IRAN: GEOLOGY, NORM, BIOLOGY, LNT, AND POSSIBLE REGULATORY FUN

    Energy Technology Data Exchange (ETDEWEB)

    Karam, P. A.

    2002-02-25

    The city of Ramsar Iran hosts some of the highest natural radiation levels on earth, and over 2000 people are exposed to radiation doses ranging from 1 to 26 rem per year. Curiously, inhabitants of this region seem to have no greater incidence of cancer than those in neighboring areas of normal background radiation levels, and preliminary studies suggest their blood cells experience fewer induced chromosomal abnormalities when exposed to 150 rem ''challenge'' doses of radiation than do the blood cells of their neighbors. This paper will briefly describe the unique geology that gives Ramsar its extraordinarily high background radiation levels. It will then summarize the studies performed to date and will conclude by suggesting ways to incorporate these findings (if they are borne out by further testing) into future radiation protection standards.

  18. Background carbon-14 levels in UK foodstuffs, 1981-1995, based upon a 1992 survey

    International Nuclear Information System (INIS)

    Otlet, R.L.; Walker, A.J.; Fulker, M.J.; Collins, C.

    1997-01-01

    Knowledge of the current 'natural' background level is important to 14 C-related studies, especially dose assessments in the vicinity of and distant from nuclear establishments since its value must be subtracted from measured levels to determine local enhancement. Although measurements have been made world-wide to monitor the decline of the background level, from its peak in the early 1960s to the present, there exists a paucity of precise data for UK natural materials. Accordingly this study was carried out to establish an average figure for the 'natural' 14 C level in foodstuffs in 1992 from a survey of materials collected from a wide range of sites over England and Wales, using this single year value, to infill missing years prior to 1992 and to extrapolate from some years afterwards. Results are presented from the survey, and for the derived extrapolation with comparison made with measurements from other laboratories. (Author)

  19. Examination of background contamination levels for gas counting and AMS target preparation in Trondheim

    DEFF Research Database (Denmark)

    Gulliksen, S.; Thomsen, M.S.

    1992-01-01

    conventional gas proportional counting (GPC) system. We have also studied contamination levels of our target preparation for C-14 accelerator mass spectrometry (AMS) dating in Uppsala. A significant lower background is obtained for Icelandic double spar than for marbles, probably due to a crystal structure...

  20. Objectively assessed recess physical activity in girls and boys from high and low socioeconomic backgrounds.

    Science.gov (United States)

    Baquet, Georges; Ridgers, Nicola D; Blaes, Aurélie; Aucouturier, Julien; Van Praagh, Emmanuel; Berthoin, Serge

    2014-02-21

    The school environment influences children's opportunities for physical activity participation. The aim of the present study was to assess objectively measured school recess physical activity in children from high and low socioeconomic backgrounds. Four hundred and seven children (6-11 years old) from 4 primary schools located in high socioeconomic status (high-SES) and low socioeconomic status (low-SES) areas participated in the study. Children's physical activity was measured using accelerometry during morning and afternoon recess during a 4-day school week. The percentage of time spent in light, moderate, vigorous, very high and in moderate- to very high-intensity physical activity were calculated using age-dependent cut-points. Sedentary time was defined as 100 counts per minute. Boys were significantly (p active than girls. No difference in sedentary time between socioeconomic backgrounds was observed. The low-SES group spent significantly more time in light (p physical activity compared to the high-SES group. High-SES boys and girls spent significantly more time in moderate (p physical activity than low-SES boys. Differences were observed in recess physical activity levels according to socioeconomic background and sex. These results indicate that recess interventions should target children in low-SES schools.

  1. Investigation of background radiation levels and geologic unit profiles in Durango, Colorado

    International Nuclear Information System (INIS)

    Triplett, G.H.; Foutz, W.L.; Lesperance, L.R.

    1989-11-01

    As part of the Uranium Mill Tailings Remedial Action (UMTRA) Project, Oak Ridge National Laboratory (ORNL) has performed radiological surveys on 435 vicinity properties (VPs) in the Durango area. This study was undertaken to establish the background radiation levels and geologic unit profiles in the Durango VP area. During the months of May through June, 1986, extensive radiometric measurements and surface soil samples were collected in the Durango VP area by personnel from ORNL's Grand Junction Office. A majority of the Durango VP surveys were conducted at sites underlain by Quaternary alluvium, older Quaternary gravels, and Cretaceous Lewis and Mancos shales. These four geologic units were selected to be evaluated. The data indicated no formation anomalies and established regional background radiation levels. Durango background radionuclide concentrations in surface soil were determined to be 20.3 ± 3.4 pCi/g for 40 K, 1.6 ± 0.5 pCi/g for 226 Ra, and 1.2 ± 0.3 pCi/g for 232 Th. The Durango background gamma exposure rate was found to be 16.5 ± 1.3 μR/h. Average gamma spectral count rate measurements for 40 K, 226 Ra and 232 Th were determined to be 553, 150, and 98 counts per minute (cpm), respectively. Geologic unit profiles and Durango background radiation measurements are presented and compared with other areas. 19 refs., 15 figs., 5 tabs

  2. High-level-waste immobilization

    International Nuclear Information System (INIS)

    Crandall, J.L.

    1982-01-01

    Analysis of risks, environmental effects, process feasibility, and costs for disposal of immobilized high-level wastes in geologic repositories indicates that the disposal system safety has a low sensitivity to the choice of the waste disposal form

  3. High resolution gamma spectrometry of size-separated soils from high background areas of Kerala

    International Nuclear Information System (INIS)

    Menon, M.R.; Sadasivan, S.; Nambi, K.S.V.

    1992-01-01

    Soil samples from a high background area of Kerala were analysed for their natural radionuclide content and distribution with particle size. The samples exhibited inhomogeneity in activity distribution. The smaller size particles had higher activity. The open air dose estimates are also presented. (author). 5 refs., 2 tabs

  4. Radiation dose in the high background radiation area in Kerala, India.

    Science.gov (United States)

    Christa, E P; Jojo, P J; Vaidyan, V K; Anilkumar, S; Eappen, K P

    2012-03-01

    A systematic radiological survey has been carried out in the region of high-background radiation area in Kollam district of Kerala to define the natural gamma-radiation levels. One hundred and forty seven soil samples from high-background radiation areas and five samples from normal background region were collected as per standard sampling procedures and were analysed for (238)U, (232)Th and (40)K by gamma-ray spectroscopy. External gamma dose rates at all sampling locations were also measured using a survey meter. The activities of (238)U, (232)Th and (40)K was found to vary from 17 to 3081 Bq kg(-1), 54 to 11976 Bq kg(-1) and BDL (67.4 Bq kg(-1)) to 216 Bq kg(-1), respectively, in the study area. Such heterogeneous distribution of radionuclides in the region may be attributed to the deposition phenomenon of beach sand soil in the region. Radium equivalent activities were found high in several locations. External gamma dose rates estimated from the levels of radionuclides in soil had a range from 49 to 9244 nGy h(-1). The result of gamma dose rate measured at the sampling sites using survey meter showed an excellent correlation with dose rates computed from the natural radionuclides estimated from the soil samples.

  5. Background levels and radiation dose yield of o-tyrosine in chicken meat

    International Nuclear Information System (INIS)

    Chuaqui-Offermanns, N.; McDougall, T.

    1991-01-01

    The measurement of o-tyrosine levels in poultry meat is a potential method for postirradiation dosimetry of poultry. The validity of using o-tyrosine for this purpose has not yet been established. As part of the validation process, the o-tyrosine content in unirradiated chicken meat, the radiation dose response curve, and the effects of postirradiation storage on o-tyrosine levels are examined. In 18 individual samples, the mean background level of o-tyrosine was 0.18 +/- 0.11 ppm (wet weight, 70% moisture), and the most frequent background level (60% of the cases) was between 0.05 and 0.15 ppm (wet weight, 70% moisture). In pooled samples of 10 chickens, the mean background level was 0.12 +/- 0.03 ppm (wet weight, 70% moisture). The levels were not significantly affected by storage at 5 degrees C (7 d) or by freezing the sample. The radiation dose response curve was linear within the dose range studied (0 to 10 kGy), with a slope of 0.127 + 0.003 ppm (wet weight)/kGy. Although there was some variation in the intercept (0.132 + 0.013), the slope was the same in all samples tested. Postirradiation storage at either 4 or 8 degrees C until spoilage did not affect the levels of o-tyrosine. These data indicate that o-tyrosine level may be useful for determining the absorbed dose in chicken meat gamma-irradiated to doses greater than 0.6 kGy. Further validation studies are continuing

  6. Sources and levels of background noise in the NASA Ames 40- by 80-foot wind tunnel

    Science.gov (United States)

    Soderman, Paul T.

    1988-01-01

    Background noise levels are measured in the NASA Ames Research Center 40- by 80-Foot Wind Tunnel following installation of a sound-absorbent lining on the test-section walls. Results show that the fan-drive noise dominated the empty test-section background noise at airspeeds below 120 knots. Above 120 knots, the test-section broadband background noise was dominated by wind-induced dipole noise (except at lower harmonics of fan blade-passage tones) most likely generated at the microphone or microphone support strut. Third-octave band and narrow-band spectra are presented for several fan operating conditions and test-section airspeeds. The background noise levels can be reduced by making improvements to the microphone wind screen or support strut. Empirical equations are presented relating variations of fan noise with fan speed or blade-pitch angle. An empirical expression for typical fan noise spectra is also presented. Fan motor electric power consumption is related to the noise generation. Preliminary measurements of sound absorption by the test-section lining indicate that the 152 mm thick lining will adequately absorb test-section model noise at frequencies above 300 Hz.

  7. Background levels of methane in Mars’ atmosphere show strong seasonal variations

    Science.gov (United States)

    Webster, Christopher R.; Mahaffy, Paul R.; Atreya, Sushil K.; Moores, John E.; Flesch, Gregory J.; Malespin, Charles; McKay, Christopher P.; Martinez, German; Smith, Christina L.; Martin-Torres, Javier; Gomez-Elvira, Javier; Zorzano, Maria-Paz; Wong, Michael H.; Trainer, Melissa G.; Steele, Andrew; Archer, Doug; Sutter, Brad; Coll, Patrice J.; Freissinet, Caroline; Meslin, Pierre-Yves; Gough, Raina V.; House, Christopher H.; Pavlov, Alexander; Eigenbrode, Jennifer L.; Glavin, Daniel P.; Pearson, John C.; Keymeulen, Didier; Christensen, Lance E.; Schwenzer, Susanne P.; Navarro-Gonzalez, Rafael; Pla-García, Jorge; Rafkin, Scot C. R.; Vicente-Retortillo, Álvaro; Kahanpää, Henrik; Viudez-Moreiras, Daniel; Smith, Michael D.; Harri, Ari-Matti; Genzer, Maria; Hassler, Donald M.; Lemmon, Mark; Crisp, Joy; Sander, Stanley P.; Zurek, Richard W.; Vasavada, Ashwin R.

    2018-06-01

    Variable levels of methane in the martian atmosphere have eluded explanation partly because the measurements are not repeatable in time or location. We report in situ measurements at Gale crater made over a 5-year period by the Tunable Laser Spectrometer on the Curiosity rover. The background levels of methane have a mean value 0.41 ± 0.16 parts per billion by volume (ppbv) (95% confidence interval) and exhibit a strong, repeatable seasonal variation (0.24 to 0.65 ppbv). This variation is greater than that predicted from either ultraviolet degradation of impact-delivered organics on the surface or from the annual surface pressure cycle. The large seasonal variation in the background and occurrences of higher temporary spikes (~7 ppbv) are consistent with small localized sources of methane released from martian surface or subsurface reservoirs.

  8. 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

  9. Determining site-specific background level with geostatistics for remediation of heavy metals in neighborhood soils

    OpenAIRE

    Tammy M. Milillo; Gaurav Sinha; Joseph A. Gardella Jr.

    2017-01-01

    The choice of a relevant, uncontaminated site for the determination of site-specific background concentrations for pollutants is critical for planning remediation of a contaminated site. The guidelines used to arrive at concentration levels vary from state to state, complicating this process. The residential neighborhood of Hickory Woods in Buffalo, NY is an area where heavy metal concentrations and spatial distributions were measured to plan remediation. A novel geostatistics based decision ...

  10. High Level Radioactive Waste Management

    International Nuclear Information System (INIS)

    1991-01-01

    The proceedings of the second annual international conference on High Level Radioactive Waste Management, held on April 28--May 3, 1991, Las Vegas, Nevada, provides information on the current technical issue related to international high level radioactive waste management activities and how they relate to society as a whole. Besides discussing such technical topics as the best form of the waste, the integrity of storage containers, design and construction of a repository, the broader social aspects of these issues are explored in papers on such subjects as conformance to regulations, transportation safety, and public education. By providing this wider perspective of high level radioactive waste management, it becomes apparent that the various disciplines involved in this field are interrelated and that they should work to integrate their waste management activities. Individual records are processed separately for the data bases

  11. High-level Petri Nets

    DEFF Research Database (Denmark)

    various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets. Within the Petri net community this problem has been discussed many times, and as an outcome this book has been compiled. The book contains reprints...... of some of the most important papers on the application and theory of high-level Petri nets. In this way it makes the relevant literature more available. It is our hope that the book will be a useful source of information and that, e.g., it can be used in the organization of Petri net courses. To make......High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable descriptions than can be obtained by means...

  12. Background differences in baseline and stimulated MMP levels influence abdominal aortic aneurysm susceptibility

    Science.gov (United States)

    Dale, Matthew A.; Ruhlman, Melissa K.; Zhao, Shijia; Meisinger, Trevor; Gu, Linxia; Swier, Vicki J.; Agrawal, Devendra K.; Greiner, Timothy C.; Carson, Jeffrey S.; Baxter, B. Timothy; Xiong, Wanfen

    2015-01-01

    Objective Evidence has demonstrated profound influence of genetic background on cardiovascular phenotypes. Murine models in Marfan syndrome (MFS) have shown that genetic background-related variations affect thoracic aortic aneurysm formation, rupture, and lifespan of mice. MFS mice with C57Bl/6 genetic background are less susceptible to aneurysm formation compared to the 129/SvEv genetic background. In this study, we hypothesize that susceptibility to abdominal aortic aneurysm (AAA) will be increased in 129/SvEv mice versus C57Bl/6 mice. We tested this hypothesis by assessing differences in aneurysm size, tissue properties, immune response, and MMP expression. Methods Mice of C57Bl/6 or 129/SvEv background underwent AAA induction by periaortic application of CaCl2. Baseline aortic diameters, tissue properties and MMP levels were measured. After aneurysm induction, diameters, MMP expression, and immune response (macrophage infiltration and bone marrow transplantation) were measured. Results Aneurysms were larger in 129/SvEv mice than C57Bl/6 mice (83.0% ± 13.6 increase compared to 57.8% ± 6.4). The aorta was stiffer in the 129/SvEv mice compared to C57Bl/6 mice (952.5 kPa ± 93.6 versus 621.4 kPa ± 84.2). Baseline MMP-2 and post-aneurysm MMP-2 and -9 levels were higher in 129/SvEv aortas compared to C57Bl/6 aortas. Elastic lamella disruption/fragmentation and macrophage infiltration were increased in 129/SvEv mice. Myelogenous cell reversal by bone marrow transplantation did not affect aneurysm size. Conclusions These data demonstrate that 129/SvEv mice are more susceptible to AAA compared to C57Bl/6 mice. Intrinsic properties of the aorta between the two strains of mice, including baseline expression of MMP-2, influence susceptibility to AAA. PMID:26546710

  13. Background noise levels and correlation with ship traffic in the Gulf of Catania

    Science.gov (United States)

    Viola, Salvatore; Buscaino, Giuseppa; Caruso, Francesco; Chierici, Francesco; Embriaco, Davide; Favali, Paolo; Giovanetti, Gabriele; Grammauta, Roasario; Larosa, Giuseppina; Pavan, Gianni; Pellegrino, Carmelo; Pulvirenti, Sara; Riccobene, Giorgio; Sciacca, Virginia; Simeone, Francesco; Beranzoli, Laura; Marinaro, Giuditta

    2015-04-01

    In the last decades the growing interest in the evaluation of the underwater acoustic noise for studies in the fields of geology, biology and high-energy physics is driving the scientific community to collaborate towards a multidisciplinary approach to the topic. In June 2012 in the framework of the European project EMSO, a multidisciplinary underwater observatory, named NEMO-SN1, was installed 25 km off-shore the port of Catania, at a depth of 2100 m and operated until May 2013 by INFN (Istituto Nazionale di Fisica Nucleare) and INGV (Istituto Nazionale di Geofisica e Vulcanologia). NEMO-SN1 hosted aboard geophysical, oceanographic and acoustic sensors: among these a seismic hydrophone model SMID DT-405D(V). In this work, conducted within the activity of the SMO project, the results on the evaluation of the underwater acoustic pollution in the Gulf of Catania through SMID DT-405D(V) recordings are presented. The seismic hydrophone provided a data set of about 11 months of continuous (24/7) recordings. Underwater sounds have been continuously digitized at a sampling frequency of 2 kHz and the acquired data have been stored in 10min long files for off-line analysis. To describe one-year background noise levels, the mean integrated acoustic noise was measured every second (sampling frequency 2000, NFFT 2048) in the 1/3 octave bands with centre frequency 63 Hz and for each 10 minutes-long file the 5th, the 50th and the 98th percentiles were calculated. Measured noise was correlated with the shipping traffic in the area, thanks to the data provided by an AIS receiver installed at the INFN-Laboratori Nazionali del Sud. An acoustic noise increment was measured in coincidence with the passing of crafts in the area and it was possible to identify the characteristic spectrum of each ship. A simple model for the estimation of the acoustic noise induced by the ships passing through the area was developed. The model was applied by using AIS data acquired during the operation

  14. The CMS High-Level Trigger

    International Nuclear Information System (INIS)

    Covarelli, R.

    2009-01-01

    At the startup of the LHC, the CMS data acquisition is expected to be able to sustain an event readout rate of up to 100 kHz from the Level-1 trigger. These events will be read into a large processor farm which will run the 'High-Level Trigger'(HLT) selection algorithms and will output a rate of about 150 Hz for permanent data storage. In this report HLT performances are shown for selections based on muons, electrons, photons, jets, missing transverse energy, τ leptons and b quarks: expected efficiencies, background rates and CPU time consumption are reported as well as relaxation criteria foreseen for a LHC startup instantaneous luminosity.

  15. The CMS High-Level Trigger

    CERN Document Server

    Covarelli, Roberto

    2009-01-01

    At the startup of the LHC, the CMS data acquisition is expected to be able to sustain an event readout rate of up to 100 kHz from the Level-1 trigger. These events will be read into a large processor farm which will run the "High-Level Trigger" (HLT) selection algorithms and will output a rate of about 150 Hz for permanent data storage. In this report HLT performances are shown for selections based on muons, electrons, photons, jets, missing transverse energy, tau leptons and b quarks: expected efficiencies, background rates and CPU time consumption are reported as well as relaxation criteria foreseen for a LHC startup instantaneous luminosity.

  16. The CMS High-Level Trigger

    Science.gov (United States)

    Covarelli, R.

    2009-12-01

    At the startup of the LHC, the CMS data acquisition is expected to be able to sustain an event readout rate of up to 100 kHz from the Level-1 trigger. These events will be read into a large processor farm which will run the "High-Level Trigger" (HLT) selection algorithms and will output a rate of about 150 Hz for permanent data storage. In this report HLT performances are shown for selections based on muons, electrons, photons, jets, missing transverse energy, τ leptons and b quarks: expected efficiencies, background rates and CPU time consumption are reported as well as relaxation criteria foreseen for a LHC startup instantaneous luminosity.

  17. Background compensated GM counter for the measurement of low level #betta#-activity

    International Nuclear Information System (INIS)

    Mori, C.; Kumanomido, H.; Watanabe, T.

    1983-01-01

    When low level activity of a #betta#-ray source or surface contamination is to be measured with a GM counter, it is desirable to obtain a net count without background count through a single measurement. An end-window GM counter for such a purpose was constructed. The counter has a diaphragm to divide it into two parts. The front part, the window side, can detect #betta#-rays and background radiations, while the rear part only detects background, since #betta#-rays coming through the front are absorbed by the diaphragm. In the counter type I, the sensitive volumes of the two parts are the same and the anode wire of the front is connected to that of the rear through an electric resistor which leads to yielding different pulse heights and rise times. The net count of #betta#-rays can be obtained through a single measurement by subtracting the count in the rear part from that in the front part. In the counter type II, the lengths of the anode wires of the two parts are different, which gives rise to different pulse heights. With a background compensated GM counter, it is possible to shorten the measuring time, keeping nearly the same accuracy compared with a conventional GM counter. (orig.)

  18. High-Level Radioactive Waste.

    Science.gov (United States)

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  19. High-level radioactive wastes

    International Nuclear Information System (INIS)

    Grissom, M.C.

    1982-10-01

    This bibliography contains 812 citations on high-level radioactive wastes included in the Department of Energy's Energy Data Base from January 1981 through July 1982. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number

  20. Cytogenetic investigation in a population living in the high background radiation area in China

    Energy Technology Data Exchange (ETDEWEB)

    Deqing, C.

    1980-04-01

    On the basis of the previous investigation, 24,000 metaphases of the lymphocytes of 120 inhabitants from Tongyou region, where the highest individual cummulative exposure per year of 372 mR in weighted average was recorded in the high background radiation area selected, have been analysed with the method recommended by WHO in 1973, in order to determine the extent of human chromosome aberrations induced by the high background radiation of various levels. The results show that the difference between the total number of chromosome breakages in the individuals living in the high background radiation area and that in the control area (0.32x10/sup -2/ and 0.27x10/sup -2/ per cell respectively) is not significant whereas that between the numbers of two-hite aberrations (mainly dicentric) in the same two groups (0.042x10/sup -2/ and 0.0048x10/sup -2/ per cell) is significant (X/sup 2/ = 6.1475, P<0.05). In addition, the normal value of the chromosome aberrations of human lymphocytes was analyzed.

  1. Background radon levels in Germany and how to take them into account in radiological evaluations

    International Nuclear Information System (INIS)

    Gehrcke, K.; Kuemmel, M.; Dushe, C.

    2008-01-01

    A mean background radon level of 9 ±, 1 Bq/m 3 was determined for Germany as a whole. This value is lower by about 5 Bq/m3 compared to previous, less representative measurements. For 17 former mining areas in the east of Germany representative regional background levels were derived. Characteristic limits (decision thresholds and detection limits) were determined for these areas to facilitate statistically sound decisions in the radiological evaluation of mining legacies. The detection limits for the anthropogenic contribution to the radon concentration vary from 10 to more than 20 Bq/m 3 in the different mining areas. Especially the higher values are governed by the spatial and temporal variability of the background concentrations rather than measurement uncertainties. The fact that man-made contributions of partly more than 20 Bq/m3 cannot be detected with sufficient statistical accuracy has to be taken into account in radiological investigations and evaluations of mining legacies. (author)(tk)

  2. Background studies of high energy γ rays from (n,γ) reactions in the CANDLES experiment

    Science.gov (United States)

    Nakajima, K.; Iida, T.; Akutagawa, K.; Batpurev, T.; Chan, W. M.; Dokaku, F.; Fushimi, K.; Kakubata, H.; Kanagawa, K.; Katagiri, S.; Kawasaki, K.; Khai, B. T.; Kino, H.; Kinoshita, E.; Kishimoto, T.; Hazama, R.; Hiraoka, H.; Hiyama, T.; Ishikawa, M.; Li, X.; Maeda, T.; Matsuoka, K.; Moser, M.; Nomachi, M.; Ogawa, I.; Ohata, T.; Sato, H.; Shamoto, K.; Shimada, M.; Shokati, M.; Takahashi, N.; Takemoto, Y.; Takihira, Y.; Tamagawa, Y.; Tozawa, M.; Teranishi, K.; Tetsuno, K.; Trang, V. T. T.; Tsuzuki, M.; Umehara, S.; Wang, W.; Yoshida, S.; Yotsunaga, N.

    2018-07-01

    High energy γ rays with several MeV produced by (n,γ) reactions can be a trouble for low background measurements in the underground laboratories such as double beta decay experiments. In the CANDLES project, which aimed to observe the neutrino-less double beta decay from 48Ca, γ rays caused by (n,γ) reactions were found to be the most significant background. The profile of the background was studied by measurements with a neutron source and a simulation with a validity check of neutron processes in Geant4. The observed spectrum of γ rays from (n,γ) reactions was well reproduced by the simulated spectra, which were originated from the surrounding rock and a detector tank made of stainless steel. The environmental neutron flux was derived by the observed event rate of γ rays from (n,γ) reactions using the simulation. The thermal and non-thermal neutron flux were found to be (1.3 ± 0.6) ×10-6 cm-2s-1 and (1.1 ± 0.5) ×10-5 cm-2s-1 , respectively. It is necessary to install an additional shield to reduce the background from (n,γ) reaction to the required level.

  3. In vivo measurement of uranium in the human chest under high background conditions

    International Nuclear Information System (INIS)

    Kruger, P.J.; Feather, J.I.

    1981-08-01

    The use of a low-background counting room was considered essential for in vivo gamma counting of uranium in the human chest. When such measurements were, however, carried out under relatively high background conditions, this necessitated a new method of analysis. It was found that a linear relationship between LnN and E exists for each individual where N is the count rate per keV and E the energy in keV, for gamma energies between 90 keV and 300 keV. The displacements from this straight line at the energy values of 90 and 186 keV then represent the contribution of the uranium present. These displacements were calibrated for natural uranium. It was possible to detect contamination levels of lower than half MPLB [af

  4. Correlation Among Students’ Family Background, Academic Performance in Junior High School, and Senior High School Tracking in Taiwan

    Directory of Open Access Journals (Sweden)

    Ming-Fu Huang

    2014-12-01

    Full Text Available There were numerous previous studies on educational tracking. However, most of the data adopted in these studies were collected a decade ago, involving sample population 20-64 years of age. Among them, many elderly samples had undergone senior high school tracking in the early years. The present study used the data of students and parents from the 3rd wave (2005 of the Taiwan Education Panel Survey (TEPS. A path analysis was conducted to investigate the inequality of opportunities involved in the influence of student family background on educational tracking at the senior high school stage. The results show: although the overall percentage of junior high school graduates entering advanced levels was approximately 100% and almost all students of different family backgrounds entered advanced levels, the most crucial factor among those affecting educational tracking of senior high school stage was students’ academic performance during junior high school. Students with higher family socioeconomic status and fewer siblings showed better academic performance in junior high schools, and consequently had higher possibilities of entering public senior high schools leading to a more promising future. This indicates that though the inequality in the quantity of opportunities approached 0, the inequality in the quality of opportunities still remained, which fails to support the hypothesis of the maximally maintained inequality of educational opportunity (MMI; however, the result supports the hypothesis of the effectively maintained inequality of educational opportunity (EMI.

  5. Impact of fertilizers on background radioactivity level of two newly developed farms in Western Desert, Egypt

    International Nuclear Information System (INIS)

    Ahmad, F.

    2006-01-01

    A survey of soil and plants were carried out to determine the environmental gamma background radiation levels of two newly developed farms in western desert area, Egypt. The materials and the standards were analyzed by gamma spectroscopy in which a shielded high purity germanium detector has been used to measure the natural concentration of 238 U, 232 Th and 40 K activities in the samples. The radionuclide contents in some commercial fertilizers have been determined. The results of analysis of specific activities in the fertilizers under study were 1.27-950.09 Bq/Kg for 238 U, 0.73 -162.16 Bq/Kg for 232 Th and 10.22- 23845.24 Bq/Kg for 40 K. All natural soil samples showed low activity concentrations. The concentrations of 238 U (6.13-38.84 Bq/Kg) and 232 Th (2.58-25.69 Bq/Kg) were quite similar, while that of 40 K (113.91-9314.11 Bq/Kg) was the highest for plant samples. Some of the results obtained were higher than the permissible international radioactivity levels. It is suitable in this regard to compare the activity values for the imported fertilizers and that fabricated in Egypt. The absorbed dose rate and the radium equivalent activity concentration were found to be 1.91-1027 n Gy/h and 4.02-1840.98 Bq/Kg, respectively, for fertilizers samples. For soil and plant samples, the results were 11.86-415.29 n Gy/h and 24.20-750.52 Bq/Kg for the absorbed dose rate and the radium equivalent activity concentration, respectively, and the banana plant contained the largest values. The present study presents actual data from investigations of the plant-soil transfer of the primordial radio nuclides for some fruits growing at these soils. The transfer factors of 0.35-1.821 for 238 U, 0.227-0.480 for 232 Th and 1.95-31.85 for 40 K were obtained. The increase of the transfer of 40 K reflected its great uptake to the fruits. The observed plant-soil factors were varied widely, mainly as a result of different soil, vegetation types and environmental conditions. Taking into

  6. RPython high-level synthesis

    Science.gov (United States)

    Cieszewski, Radoslaw; Linczuk, Maciej

    2016-09-01

    The development of FPGA technology and the increasing complexity of applications in recent decades have forced compilers to move to higher abstraction levels. Compilers interprets an algorithmic description of a desired behavior written in High-Level Languages (HLLs) and translate it to Hardware Description Languages (HDLs). This paper presents a RPython based High-Level synthesis (HLS) compiler. The compiler get the configuration parameters and map RPython program to VHDL. Then, VHDL code can be used to program FPGA chips. In comparison of other technologies usage, FPGAs have the potential to achieve far greater performance than software as a result of omitting the fetch-decode-execute operations of General Purpose Processors (GPUs), and introduce more parallel computation. This can be exploited by utilizing many resources at the same time. Creating parallel algorithms computed with FPGAs in pure HDL is difficult and time consuming. Implementation time can be greatly reduced with High-Level Synthesis compiler. This article describes design methodologies and tools, implementation and first results of created VHDL backend for RPython compiler.

  7. Single-photon detector operating under extremely high background photon flux conditions

    International Nuclear Information System (INIS)

    Prochazka, Ivan; Sopko, Bruno; Blazej, Josef

    2009-01-01

    We are reporting our results in research and development in the field of avalanche semiconductor single-photon detectors and their application. Our goal was a development of a solid-state photon-counting detector capable of high-precision photon arrival time tagging in extremely harsh operating conditions. The background photon flux exceeding 10 9 photons per second hitting the detector active area should not avoid the useful signal detection and recognition on the signal level of units of photons per second. This is background photon flux about two orders of magnitude higher than what the conventional solid-state photon counters accept. The detection timing resolution should be better than 100 ps and the delay stability should be on picosecond level. We have developed and tested the active quenched and gated avalanche structure on silicon providing the required features in connection with the K14 detection chips. The detector is capable of gated operation under the conditions of background photon flux of 5x10 9 photons per second. The operational detector tolerates long term exposures to the input photon flux exceeding 10 15 photons (>1 mW) per second without damage.

  8. The noise background and its suppression in high energy physics experiment

    International Nuclear Information System (INIS)

    Meng Xiangcheng

    1996-01-01

    In the modern high energy physics experiments, system is very complicated and from a lot of sources may originate noise and background. How to reduce and restrain noise and backgrounds? It should use different suppression mode for different kinds of noise and backgrounds

  9. Transcriptome analysis reveals a stress response of Shewanella oneidensis deprived of background levels of ionizing radiation

    Science.gov (United States)

    Li, Xiaoping; Schilkey, Faye; Smith, Geoffrey B.

    2018-01-01

    Natural ionizing background radiation has exerted a constant pressure on organisms since the first forms of life appeared on Earth, so that cells have developed molecular mechanisms to avoid or repair damages caused directly by radiation or indirectly by radiation-induced reactive oxygen species (ROS). In the present study, we investigated the transcriptional effect of depriving Shewanella oneidensis cultures of background levels of radiation by growing the cells in a mine 655 m underground, thus reducing the dose rate from 72.1 to 0.9 nGy h-1 from control to treatment, respectively. RNASeq transcriptome analysis showed the differential expression of 4.6 and 7.6% of the S. oneidensis genome during early- and late-exponential phases of growth, respectively. The greatest change observed in the treatment was the downregulation of ribosomal proteins (21% of all annotated ribosomal protein genes during early- and 14% during late-exponential) and tRNA genes (14% of all annotated tRNA genes in early-exponential), indicating a marked decrease in protein translation. Other significant changes were the upregulation of membrane transporters, implying an increase in the traffic of substrates across the cell membrane, as well as the up and downregulation of genes related to respiration, which could be interpreted as a response to insufficient oxidants in the cells. In other reports, there is evidence in multiple species that some ROS not just lead to oxidative stress, but act as signaling molecules to control cellular metabolism at the transcriptional level. Consistent with these reports, several genes involved in the metabolism of carbon and biosynthesis of amino acids were also regulated, lending support to the idea of a wide metabolic response. Our results indicate that S. oneidensis is sensitive to the withdrawal of background levels of ionizing radiation and suggest that a transcriptional response is required to maintain homeostasis and retain normal growth. PMID:29768440

  10. Background level of natural radioactivities in a giant water Cherenkov detector and its surrounding environment; KAMIOKANDE-II

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masayoshi; Sakanoue, Masanobu; Komura, Kazuhisa; Ueno, Kaoru [Kanazawa Univ., Tatsunokuchi, Ishikawa (Japan). Low Level Radioactivity Lab.

    1989-12-01

    The KAMIOKANDE-II water Cherenkov detector for the measurement of nucleon decay and/or solar neutrino has been operating in the underground laboratory at a depth of 2,700 m.w.e. (meter water equivalent) in Kamioka mine of Gifu Prefecture. Concentrations of {sup 238}U, {sup 232}Th, {sup 226}Ra and {sup 222}Rn as the major background sources have been measured for various kinds of rocks, mine water, mine air and high purity water used as a detector during the period from August 1986 to December 1987. The concentration levels of these radionuclides and their seasonal variation have become clear. Some of these results have provided useful informations for decreasing the background level of water Cherenkov detector. (author).

  11. Background Acoustics Levels in the 9x15 Wind Tunnel and Linear Array Testing

    Science.gov (United States)

    Stephens, David

    2011-01-01

    The background noise level in the 9x15 foot wind tunnel at NASA Glenn has been documented, and the results compare favorably with historical measurements. A study of recessed microphone mounting techniques was also conducted, and a recessed cavity with a micronic wire mesh screen reduces hydrodynamic noise by around 10 dB. A three-microphone signal processing technique can provide additional benefit, rejecting up to 15 dB of noise contamination at some frequencies. The screen and cavity system offers considerable benefit to test efficiency, although there are additional calibration requirements.

  12. Leptin levels distribution and ethnic background in two populations from Chile: Caucasian and Mapuche groups.

    Science.gov (United States)

    Pérez-Bravo, F; Albala, C; Santos, J L; Yañez, M; Carrasco, E

    1998-10-01

    Leptin, the product of the human ob gene is increased in obese individuals, suggesting resistance to its effect. We examined the relationship of serum leptin levels with respect to obesity, gender and insulin levels in two populations with different ethnic compositions in Chile. Leptin and insulin levels were determined by radioimmunoassay (RIA) and correlated with body mass index (BMI), gender and ethnic background. 79 Caucasian subjects from Santiago and 65 Mapuche natives from the Araucania region, Chile, were included in this study. Leptin concentrations in obese subjects were significantly increased in both ethnic groups in relation to lean status: Caucasian and Mapuche obese 19.3 +/- 11.6 and 10.1 +/- 5.8 (P Mapuche lean 10.4 +/- 5.8 and 4.7 +/- 2.9 (P Mapuche and Caucasian groups, similar leptin levels were observed among the males of the two populations in both metabolic states (lean and obese). In contrast, the leptin level distributions between women showed a marked difference, having a minor value in the Mapuche women with a comparable value with the male group in this ethnic population. The leptin concentrations are associated with obesity in both ethnic groups in Chile. However, the leptin levels between the Mapuche natives were significantly decreased compared to the Caucasian group. The gender distribution does not seem to be important in the Mapuche natives. The ethnic composition seems to be important in the leptin distribution in the analysed populations.

  13. Radiation and Background Levels in a CLIC Detector due to Beam-Beam Effects Optimisation of Detector Geometries and Technologies

    CERN Document Server

    Sailer, André; Lohse, Thomas

    2013-01-10

    The high charge density---due to small beam sizes---and the high energy of the proposed CLIC concept for a linear electron--positron collider with a centre-of-mass energy of up to 3~TeV lead to the production of a large number of particles through beam-beam interactions at the interaction point during every bunch crossing (BX). A large fraction of these particles safely leaves the detector. A still significant amount of energy will be deposited in the forward region nonetheless, which will produce secondary particles able to cause background in the detector. Furthermore, some particles will be created with large polar angles and directly cause background in the tracking detectors and calorimeters. The main sources of background in the detector, either directly or indirectly, are the incoherent $mathrm{e}^{+}mathrm{e}^{-}$ pairs and the particles from $gammagamma ightarrow$ hadron events. The background and radiation levels in the detector have to be estimated, to study if a detector is feasible, that can han...

  14. Eurasian continental background and regionally polluted levels of ozone and CO observed in northeast Asia

    Science.gov (United States)

    Pochanart, Pakpong; Kato, Shungo; Katsuno, Takao; Akimoto, Hajime

    The roles of Eurasian/Siberian continental air masses transport and the impact of large-scale East Asian anthropogenic emissions on tropospheric ozone and carbon monoxide levels in northeast Asia were investigated. Seasonal behaviors of O 3 and CO mixing ratios in background continental (BC) air masses and regionally polluted continental (RPC) air masses were identified using trajectory analyses of Eurasian continental air masses and multi-year O 3 and CO data observed at Happo, a mountain site in Japan. RPC air masses show significantly higher O 3 and CO mixing ratios (annual average of 53.9±6.0 and 200±41 ppb, respectively) than BC air masses (44.4±3.6 and 167±17 ppb, respectively). Large scale anthropogenic emissions in East Asia are suggested to contribute about 10 ppb of photochemical O 3 and 32 ppb of CO at Happo. A comparative study of O 3 and CO observed at other sites, i.e., Oki Islands and Mondy in northeast Asia, showed similarities suggesting that O 3 mixing ratios in BC air masses at Happo could be representative for remote northeast Asia. However, CO mixing ratios in BC air masses at Happo are higher than the background level in Siberia. The overestimate is probably related to an increase in the CO baseline gradient between Siberia and the East Asia Pacific rim, and perturbations by sub-grid scale pollution transport and regional-scale boreal forest fires in Siberia when the background continental air masses are transported to Japan.

  15. Assessment of background gamma radiation levels around Tummalapalle uranium mining and processing facility, Andhra Pradesh

    International Nuclear Information System (INIS)

    Rana, B.K.; Dhumale, M.R.; Molla, Samim; Rao, K.B.; Jha, S.K.; Tripathi, R.M.; Sahu, S.K.

    2018-01-01

    Natural environmental radioactivity and the associated external exposure due to gamma radiation depend primarily on the geological and geographical conditions, and appear at different levels in the soil of each region in the world. The dose received by the population in a region comprises of (i) external gamma radiation dose due to cosmic rays and primordial radionuclides; (ii) inhalation dose due to radon, thoron and their progeny, and (iii) ingestion dose due to the intake of radionuclides through the consumption of food, milk, water, etc. In this study, background gamma radiation level around Tummalapalle uranium mining and processing site was estimated by using radiation survey meter and deploying environmental TLDs. The generated data can be served as baseline for this area for future comparison for prolonged operation of the plant, for the upcoming adjacent projects and during decommissioning phase of the mine, mill and tailings pond

  16. Seasonal variation in the environmental background level of cosmic ray produced 22Na

    International Nuclear Information System (INIS)

    Tokuyama, Hideki; Igarashi, Shuichi

    1998-01-01

    22 Na (half life 2.6 year) is produced by cosmic rays, nuclear test and reactor. 7 Be (half life 53.3 day) is produced in atmosphere by reaction. 7 Be/ 22 Na activity ratio is good factor to observe the mixing process between stratosphere and troposphere atmosphere. The seasonal variation of 7 Be and 22 Na deposition, the ratio and the background level of 22 Na deposition were observed in Fukui city and reported in this paper. Very large reasonable change of 22 Na deposition was observed, especially the largest peak in winter. Because the concentration of cosmic-ray-produced nuclear in precipitation and the amount of precipitation were large in winter. 22 Na produced by the previous nuclear test was attenuated. The present 22 Na is only produced by cosmic rays, indicating the background level. 22 Na deposition at Fukui was 0.42Bq m -2 y -1 , one ten-thousandth of 7 Be deposition. 7 Be/ 22 Na activity ratio was changed in season and the largest peak was shown in autumn. In this reason, atmosphere showed relatively short residence time in the lower part of stratosphere, Mixture and exchange of atmosphere between stratosphere and troposphere were the most active in autumn. (S.Y.)

  17. Determining site-specific background level with geostatistics for remediation of heavy metals in neighborhood soils

    Directory of Open Access Journals (Sweden)

    Tammy M. Milillo

    2017-03-01

    Full Text Available The choice of a relevant, uncontaminated site for the determination of site-specific background concentrations for pollutants is critical for planning remediation of a contaminated site. The guidelines used to arrive at concentration levels vary from state to state, complicating this process. The residential neighborhood of Hickory Woods in Buffalo, NY is an area where heavy metal concentrations and spatial distributions were measured to plan remediation. A novel geostatistics based decision making framework that relies on maps generated from indicator kriging (IK and indicator co-kriging (ICK of samples from the contaminated site itself is shown to be a viable alternative to the traditional method of choosing a reference site for remediation planning. GIS based IK and ICK, and map based analysis are performed on lead and arsenic surface and subsurface datasets to determine site-specific background concentration levels were determined to be 50 μg/g for lead and 10 μg/g for arsenic. With these results, a remediation plan was proposed which identified regions of interest and maps were created to effectively communicate the results to the environmental agencies, residents and other interested parties.

  18. Measurements of environmental background radiation levels by TLD in and around the Jahangirnagar University Campus

    International Nuclear Information System (INIS)

    Mollah, A.S.; Aleya Begum; Idris Miah, M.; Yunus, Afrozi

    1997-01-01

    The background radiation levels at 30 locations in and around the Jahangirnagar University Campus (JUC) were measured using a LiF(TLD-100) thermoluminescent dosimeter (TLD). In addition, dose rates at three pre-selected locations were measured on a monthly as well as quarterly basis for one year period (July 1993 - June 1994). The dose rate ranges from 1016 to 2167 μSv.y -1 (101.6 to 216.7 mrem.y -1 ) with a mean value of 1595 μSv.y -1 (159.5 mrem.y -1 ). These values are comparable with those of pre- and post-operational values for the reactor site. The estimated average annual effective dose equivalent to the inhabitants at the study areas was found to be 1276 μSv (127.6 mrem). Variation of background radiation level with meteorological parameters, namely, temperature, rainfall, relative humidity and pressure was also studied. The influence on the dose rate of the meteorological parameters was observed. (author)

  19. Assessing Natural Background Levels of aquifers in the Metropolitan Area of Milan (Lombardy)

    Science.gov (United States)

    De Caro, Mattia; Crosta, Giovanni; Frattini, Paolo

    2016-04-01

    The European Water Framework Directive (WFD 2000/60/CE) requires Member States to evaluate the status of groundwater bodies in order to reach a good water quality for human consumption. One of the preliminary steps for defining the status of groundwater bodies consists in the definition and evaluation of the so-called Natural Background Levels (NBL). The NBL or Baseline level can be defined as "the range of concentration of a given element, isotope or chemical compound in solution, derived entirely from natural, geological, biological or atmospheric sources, under conditions not perturbed by anthropogenic activity" (Edmund and Shand, 2009). The qualitative analysis for a large area (ca 4500 Km2) of the Po Plain around the Milan Metropolitan area (Lombardy, Italy) is presented in this study. Despite the aquifers in the Milan metropolitan area are an incredible groundwater resource for a very large population (3.195.629 inhabitants in the metropolitan area, data at November 2014) and a highly industrialized area, a groundwater baseline characterization is still missing. In order to attain the hydro-geochemical characterization a complete geodatabase was built (120.655 chemical samples from 1980 to 2014). This database has been explored by classical and multivariate statistical analyses to provide relationships among the more influential lithological, hydrogeological and hydro-chemical variables. Finally, the NBLs of different chemical species which may be anthropogenic sensitive (Na, Cl, K, NO3, SO4, NH4, As, Fe, Cr, Fe, Mn, Zn) and for multiple aquifer bodies (phreatic, semi-confined and confined aquifer) are evaluated. Two different approaches are applied: the Pre-Selection method (BRIDGE, 2006) and the Component-Separation method. The first one (PS) consists in the exclusion of samples from the available dataset that could indicate human activities then deriving the NBL as the 90th percentile of the remaining data. The second one (CS) consists in the fitting of

  20. Cytogenetic study of stable chromosome aberrations in residents of a high background radiation area in China

    International Nuclear Information System (INIS)

    Zhang Wei; Wang Chunyan; Chen Deqing; Wei Lvxin

    2004-01-01

    Objective: To investigate the effect of high background radiation on the induction of stable chromosome aberrations. Methods: By fluorescence in situ hybridization (FISH) technique chromosome Nos. 1, 2 and 4 were painted using specific biotin-labeled whole chromosome painting probes. Peripheral blood specimens were taken from 31 individuals living in the high background radiation area (HRBA) and 29 individuals in the control area. Results: No significant difference was found in the frequencies of translocations between HBRA and the control (P>0.05, Mann-Whitney U test) for both children and elderly individuals. On the other hand, correlation between age and translocation frequencies was significant at the 1% level (r s =0.388 with 56DF). Conclusion: There are no differences in the frequencies of translocations between HBRA and the control area. The present result indicates that the contribution of an elevated level of natural radiation in HBRA in China to the induction rate of stable type aberrations (translocations) dose not have a significant effect compared with the contributions from all other sources such as chemical mutagens and(or) metabolic factors. (authors)

  1. Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches

    CERN Document Server

    Iguaz, F J; Aznar, F; Castel, J F; Dafni, T; Davenport, M; Ferrer-Ribas, E; Galan, J; Garcia, J A; Garza, J G; Giomataris, I; Irastorza, I G; Papaevangelou, T; Rodriguez, A; Tomas, A; Vafeiadis, T; Yildiz, S C

    2014-01-01

    Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ ...

  2. Signal-to-noise ratios of multiplexing spectrometers in high backgrounds

    Science.gov (United States)

    Knacke, R. F.

    1978-01-01

    Signal-to-noise ratios and the amount of multiplexing gain achieved with a Michelson spectrometer during detector and background noise are studied. Noise caused by the warm background is found in 10 and 20-micron atmospheric windows in high resolution Fourier spectroscopy. An equation is derived for the signal-to-noise ratio based on the number of channels, total time to obtain the complete spectrum, the signal power in one spectral element, and the detector noise equivalent power in the presence of negligible background. Similar expressions are derived for backgrounds yielding a noise equivalent power to a spectral element, and backgrounds having flat spectra in the frequency range under investigation.

  3. Problems Concerning Dose Assessments in Epidemiology of High Background Radiation Areas of Yangjiang, China (invited paper)

    International Nuclear Information System (INIS)

    Wei, L.X.; Yuan, Y.L.

    1998-01-01

    The purpose of this study on radiation levels and dose assessments in the epidemiology of a high background radiation area (HBRA) and the control area (CA) is to respond to the needs of epidemiology in these areas, where the inhabitants are continuously exposed to low dose, low dose rate ionising radiation. A brief description is given of how the research group evaluated the feasibility of the investigation by analysing the population size and the radiation levels, how simple reliable methods were used to get the individual annual dose for every cohort member, and how the cohort members were classified into various dose groups for dose-effect relationship analysis. Finally, the use of dose group classification for cancer mortality studies is described. (author)

  4. A geophysical tour of high background radiation areas of the world

    International Nuclear Information System (INIS)

    Krishnan, D.; Kher, R.K.; Nambi, K.S.V.

    1995-01-01

    A comparison of the findings including health effects in four major high natural background areas of the world are given. Such high background areas could prove to be a radiation ecology laboratory gifted by nature and provide further insight in the relation of radiation, natural or otherwise and human health. 3 refs., 2 tabs

  5. Current Background Noise Sources and Levels in the NASA Ames 40- by 80-Foot Wind Tunnel: A Status Report

    Science.gov (United States)

    Allen, Christopher S.; Jaeger, Stephen; Soderman, Paul; Koga, Dennis (Technical Monitor)

    1999-01-01

    Background noise measurements were made of the acoustic environment in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel (40x80) at NASA Ames Research Center. The measurements were acquired subsequent to the 40x80 Aeroacoustic Modernization Project, which was undertaken to improve the anechoic characteristics of the 40x80's closed test section as well as reduce the levels of background noise in the facility. The resulting 40x80 anechoic environment was described by Soderman et. al., and the current paper describes the resulting 40x80 background noise, discusses the sources of the noise, and draws comparisons to previous 40x80 background noise levels measurements. At low wind speeds or low frequencies, the 40x80 background noise is dominated by the fan drive system. To obtain the lowest fan drive noise for a given tunnel condition, it is possible in the 40x80 to reduce the fans' rotational speed and adjust the fans' blade pitch, as described by Schmidtz et. al. This idea is not new, but has now been operationally implemented with modifications for increased power at low rotational speeds. At low to mid-frequencies and at higher wind speeds, the dominant noise mechanism was thought to be caused by the surface interface of the previous test section floor acoustic lining. In order to reduce this noise mechanism, the new test section floor lining was designed to resist the pumping of flow in and out of the space between the grating slats required to support heavy equipment. In addition, the lining/flow interface over the entire test section was designed to be smoother and quieter than the previous design. At high wind speeds or high frequencies, the dominant source of background noise in the 40x80 is believed to be caused by the response of the in-flow microphone probes (required by the nature of the closed test section) to the fluctuations in the freestream flow. The resulting background noise levels are also different for probes of various

  6. Neutron detection in a high gamma-ray background with EJ-301 and EJ-309 liquid scintillators

    International Nuclear Information System (INIS)

    Stevanato, L.; Cester, D.; Nebbia, G.; Viesti, G.

    2012-01-01

    Using a fast digitizer, the neutron–gamma discrimination capability of the new liquid scintillator EJ-309 is compared with that obtained using standard EJ-301. Moreover the capability of both the scintillation detectors to identify a weak neutron source in a high gamma-ray background is demonstrated. The probability of neutron detection is PD=95% at 95% confidence level for a gamma-ray background corresponding to a dose rate of 100 μSv/h.

  7. Radon-thoron exposures in high background radiation areas: a review

    International Nuclear Information System (INIS)

    Nambi, K.S.

    1994-01-01

    The radon-thoron measurements reported in literature for the high background radiation areas (HBRAs) of the world are summarised here. The most important areas covered are the Radon Spas and the thorium bearing monazite deposits. Special mention is made of the ongoing programmes of radon-thoron survey in the monazite beach areas of India; preliminary measurements indicate significant levels of thoron exposures. The diurnal and seasonal variations are quite wide underscoring the importance of carrying out integrated measurements for meaningful assessments of population exposures. Radon-thoron inhalation dose rates upto 30 mSv/y have been measured in lran as well as India. It has been generally observed that the cumulative population doses due to radon-thoron inhalation are as high as those due to the external exposures in these HBRAs. (author). 7 refs., 2 tabs., 3 figs

  8. State background-radiation levels: results of measurements taken during 1975-1979

    International Nuclear Information System (INIS)

    Myrick, T.E.; Berven, B.A.; Haywood, F.F.

    1981-11-01

    Background radiation levels across the United States have been measured by the Off-Site Pollutant Measurements Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL). These measurements have been conducted as part of the ORNL program of radiological surveillance at inactive uranium mills and sites formerly utilized during Manhattan Engineer District and early Atomic Energy Commission projects. The measurements included determination of 226 Ra, 232 Th, and 238 U concentrations in surface soil samples and measurement of external gamma-ray exposure rates at 1 m above the ground surface at the location of soil sampling. This information is being utilized for comparative purposes to determine the extent of contamination present at the survey sites and surrounding off-site areas. The sampling program to date has provided background information at 356 locations in 33 states. External gamma-ray exposure rates were found to range from less than 1 to 34 μR/h, with an US average of 8.5 μR/h. The nationwide average concentrations of 226 Ra, 232 Th, and 238 U in surface soil were determined to be 1.1, 0.98, and 1.0 pCi/g, respectively

  9. Nutrition status in residents in the high background radiation area of Yangjiang, China

    International Nuclear Information System (INIS)

    Lei Shujie; Li Xiaojuan; Sun Quanfu; Wei Lvxin; Gen Jiwu; Wen Cuiju; Tan Huizhen; Zou Jianmin

    2007-01-01

    Objective: To investigate the current status of nutrition and examine the difference between inhabitants in the high background radiation area (HBRA) and the control area (CA). Methods: Sixty and sixty-five male farmers aged 50 and over were randomly selected from HBRA and CA, respectively. Information on dwelling history, history of disease, medical treatment and X-ray examination were collected by interview. Body height and weight were measured, and BMIs were calculated. Serum levels of total protein, albumin and globulin, triacylglycerol (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low- density lipoprotein cholesterol (LDL-C), Apo A1 and Apo B were measured. Results: There was difference in BMI distribution between the two groups. Averages of total biochemistry indexes measured were in normal range in the two groups. With adjustment to age distribution, the serum levels of total protein, albumin and triacylglycerol (TG) of residents in CA were higher than those in HBRA; high-density lipoprotein cholesterol level was higher in HBRA than that in CA. Conclusions: This serum assay of nutrients in HBRA and CA residents confirmed the results obtained from previous surveys. Both HBRA and CA residents have similar nutrition status, residents in CA consumed more animal protein and fat compared with those in HBRA. (authors)

  10. Localities With Elevated Radiation Background in the High Karst Zone of Montenegro

    International Nuclear Information System (INIS)

    Vukotic, P.; Svrkota, R.; Andjelic, T.; Zekic, R.; Antovic, N.

    2011-01-01

    Research aimed to find localities in Montenegro with an elevated terrestrial gamma background was conducted during the period 2008-2009. For this purpose, 138 localities which have geological formations known to contain minerals with potentially high concentrations of U, Th and K, were selected throughout the country for a dosimetric survey. There are four distinctive geotectonic units in Montenegro: the Adriatic-Ionian Zone (JZ), the Budva-Cukali Zone (BZ), the High Karst Zone (VK), and the Durmitor Tectonic Unit (DTJ). The central and southern parts of Montenegro belong to the VK zone, whose geological structure is predominated by Mesozoic carbonate sediments, with occurrences of red and white bauxite formations, Triassic volcanic rocks, Paleogene flysch sediments and Quaternary sediments. In total, 38 localities belonging to the VK zone were selected for field investigations of terrestrial radiation. Knowing from earlier investigations that in Montenegro the average absorbed dose-rate in the air, 1 m above the ground, is 55 nGy/h, it was arbitrarily adopted that only localities with absorbed doses at least 50 % above this average value would be considered as having a relatively elevated radiation background. Field measurements have shown that 12 of the surveyed localities in the VK zone have such elevated dose values, five of them being with the highest dose rates in Montenegro. Among these five sites, the highest dose rate (192 nGy/h) was found at a locality which lies on andesite volcanic rock, while the other four localities (131 - 149 nGy/h) lie on bauxite deposits. Compared to the other areas in the world known to have a high natural radiation background, all of these localities in Montenegro have a moderately elevated radiation level. From the 12 localities with a relatively elevated radiation background, soil samples have been collected and analyzed by gamma spectrometry to determine activity concentrations of 40K, 232Th, 235U, 238U, 226Ra and 137Cs

  11. On the stability of Einstein static universe at background level in massive bigravity

    Directory of Open Access Journals (Sweden)

    M. Mousavi

    2017-06-01

    Full Text Available We study the static cosmological solutions and their stability at background level in the framework of massive bigravity theory with Friedmann–Robertson–Walker (FRW metrics. By the modification proposed in the cosmological equations subject to a perfect fluid we obtain new solutions interpreted as the Einstein static universe. It turns out that the non-vanishing size of initial scale factor of Einstein static universe depends on the non-vanishing three-dimensional spatial curvature of FRW metrics and also the graviton's mass. By dynamical system approach and numerical analysis, we find that the extracted solutions for closed and open universes can be stable for some viable ranges of equation of state parameter, viable values of fraction of two scale factors, and viable values of graviton's mass obeying the hierarchy m<

  12. The grey areas in soil pollution risk mapping : The distinction between cases of soil pollution and increased background levels

    NARCIS (Netherlands)

    Gaast, N. van der; Leenaers, H.; Zegwaard, J.

    1998-01-01

    The progress of soil clean up in the Netherlands is severely hindered by the lack of common agreement on how to describe the grey areas of increased background levels of pollutants. In this study practical methods are proposed in which background levels are described as distribution functions within

  13. Review of epidemiological and cytogenetic studies on high background radiation area residents

    International Nuclear Information System (INIS)

    Iwasaki, Toshiyasu

    2008-01-01

    Emerging scientific knowledge in the field of radiation biology has put into question the generic use of a simple linear extrapolation of radiation effects from high to low dose or dose rate. Though the direct information of biological effects at low dose or low dose rate has been accumulated, it is still immature to mention health effects as the consequence of biological effects. As epidemiological data have been the main sources of direct information on human health effects, studies of the health of population exposed by low dose or low dose rate ionizing radiation will help to improve our understanding. In this meaning, the epidemiological studies of residents in high background radiation areas (HBRA), which are supported by us, will provide important direct information on the biological and health effects of chronic low dose rate ionizing radiation. The epidemiological results in HBRA in China showed there are no significant increases of cancer risks caused by the high background levels of ionizing radiation. From the results which come from cytogeneticl studies, the frequencies of unstable chromosomal aberrations have shown good correlation with cumulative doses in their lifetimes, which indicated it is a sensitive and informative biomarker. On the other hand, the frequencies of stable chromosomal aberrations have shown no significant difference and the frequency was much higher than that of unstable type aberrations. It suggests that mutagenic factors other than radiation contribute more than the elevated level of radiation to the induction of DNA rearrangements which could lead to the increase of cancer risk in HBRA in China. (author)

  14. Modeling Speech Level as a Function of Background Noise Level and Talker-to-Listener Distance for Talkers Wearing Hearing Protection Devices

    DEFF Research Database (Denmark)

    Bouserhal, Rachel E.; Bockstael, Annelies; MacDonald, Ewen

    2017-01-01

    Purpose: Studying the variations in speech levels with changing background noise level and talker-to-listener distance for talkers wearing hearing protection devices (HPDs) can aid in understanding communication in background noise. Method: Speech was recorded using an intra-aural HPD from 12...... complements the existing model presented by Pelegrín-García, Smits, Brunskog, and Jeong (2011) and expands on it by taking into account the effects of occlusion and background noise level on changes in speech sound level. Conclusions: Three models of the relationship between vocal effort, background noise...

  15. 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.

  16. The Influence of Decreased Levels of High Density Lipoprotein ...

    African Journals Online (AJOL)

    Background: Changes in lipoproteins levels in sickle cell disease (SCD) patients are well.known, but the physiological ramifications of the low levels observed have not been entirely resolved. Aim: The aim of this study is to evaluate the impact of decreased levels of high density lipoprotein cholesterol (HDL.c) on ...

  17. Concentrations of radionuclides in cassava growing in high background radiation area and their transfer

    Energy Technology Data Exchange (ETDEWEB)

    Jialin, Huang; Yongru, Zha; Yicao, Guo

    1985-04-01

    The concentrations of several natural radionuclides in common cassava (Manihot esculenta Crantz) growing in Yangjiang County, a high background radiation area in Guangdong Province, and their uptake from soil and distribution in the plant were investigated. The results show that the concentrations of natural uranium and thorium in cassava root are of the order of 10/sup -6/ g/kg, and those of radium-226, radium-228, lead-210 and polonium-210 are of the order of 10/sup -11/ Ci/kg. The highest level is 9.30 +- 0.30 x 10/sup -11/ Ci/kg (lead-210), and the lowest is 3.99 +- 0.20 x 10/sup -11/ Ci/kg (radium-226). The levels of natural uranium, thorium, radium-226 and polonium-210 in cassava are below the limits stipulated by the regulations for food hygiene in China, while the lead-210 level approaches the limit. It is noticeable that the highest level of radium-228 is 7.28 +- 1.03 x 10/sup -11/ Ci/kg, 10.4 times higher than the limit. The transfer of all the nuclides from soil to different parts of cassava shows a pattern contrary to that of he nuclides in the other regions where uranium-and radium-containing waste water and phosphate fertilizer are used in agriculture.

  18. Concentrations of radionuclides in cassava growing in high background radiation area and their transfer

    International Nuclear Information System (INIS)

    Huang Jialin; Zha Yongru; Guo Yicao

    1985-01-01

    The concentrations of several natural radionuclides in common cassava (Manihot esculenta Crantz) growing in Yangjiang County, a high background radiation area in Guangdong Province, and their uptake from soil and distribution in the plant were investigated. The results show that the concentrations of natural uranium and thorium in cassava root are of the order of 10 -6 g/kg, and those of radium-226, radium-228, lead-210 and polonium-210 are of the order of 10 -11 Ci/kg. The highest level is 9.30 +- 0.30 x 10 -11 Ci/kg (lead-210), and the lowest is 3.99 +- 0.20 x 10 -11 Ci/kg (radium-226). The levels of natural uranium, thorium, radium-226 and polonium-210 in cassava are below the limits stipulated by the regulations for food hygiene in China, while the lead-210 level approaches the limit. It is noticeable that the highest level of radium-228 is 7.28 +- 1.03 x 10 -11 Ci/kg, 10.4 times higher than the limit. The transfer of all he nuclides from soil to different parts of cassava shows a pattern contrary to that of he nuclides in the other regions where uranium-and radium-containing waste water and phosphate fertilizer are used in agriculture

  19. Removing high-level contaminants

    International Nuclear Information System (INIS)

    Wallace, Paula

    2013-01-01

    Full text: Using biomimicry, an Australian cleantech innovation making inroads intoChinas's industrial sector offers multiple benefits to miners and processors in Australia. Stephen Shelley, the executive chairman of Creative Water Technology (CWT), was on hand at a recent trade show to explain how his Melbourne company has developed world-class techniques in zero liquid discharge and fractional crystallization of minerals to apply to a wide range of water treatment and recycling applications. “Most existing technologies operate with high energy distillation, filters or biological processing. CWT's appliance uses a low temperature, thermal distillation process known as adiabatic recovery to desalinate, dewater and/or recycle highly saline and highly contaminated waste water,” said Shelley. The technology has been specifically designed to handle the high levels of contaminant that alternative technologies struggle to process, with proven water quality results for feed water samples with TDS levels over 300,000ppm converted to clean water with less than 20ppm. Comparatively, reverse osmosis struggles to process contaminant levels over 70,000ppm effectively. “CWT is able to reclaim up to 97% clean usable water and up to 100% of the contaminants contained in the feed water,” said Shelley, adding that soluble and insoluble contaminants are separately extracted and dried for sale or re-use. In industrial applications CWT has successfully processed feed water with contaminant levels over 650,000 mg/1- without the use of chemicals. “The technology would be suitable for companies in oil exploration and production, mining, smelting, biofuels, textiles and the agricultural and food production sectors,” said Shelley. When compared to a conventional desalination plant, the CWT system is able to capture the value in the brine that most plants discard, not only from the salt but the additional water it contains. “If you recover those two commodities... then you

  20. Ultra low energy-ultra low background high purity germanium detectors for studies on dark matter

    International Nuclear Information System (INIS)

    Soma, A.K.; Singh, V.; Singh, L.; Singh, M.K.; Wong, H.T.

    2009-01-01

    Weakly Interacting Massive Particles (WIMP) are the leading DM candidates. Super symmetric particles (SUSY) are one of the leading WIMP candidates. To probe this least explored region Taiwan EXperiments On NeutrinO collaboration is pursuing research and development program by using High Purity Germanium detectors (HPGe). These detectors offer a matured technology to scale up the detectors and achieve sub-keV level threshold i.e. few hundreds of eV, economically. The various detectors developed by the collaboration is shown in the below figure. The current goal of the collaboration is to develop detectors of kg-scale target mass, ∼100 eV threshold and low-background specification for the studies on WIMPs, μ v and neutrino - nucleus coherent scattering

  1. The ALICE Dimuon Spectrometer High Level Trigger

    CERN Document Server

    Becker, B; Cicalo, Corrado; Das, Indranil; de Vaux, Gareth; Fearick, Roger; Lindenstruth, Volker; Marras, Davide; Sanyal, Abhijit; Siddhanta, Sabyasachi; Staley, Florent; Steinbeck, Timm; Szostak, Artur; Usai, Gianluca; Vilakazi, Zeblon

    2009-01-01

    The ALICE Dimuon Spectrometer High Level Trigger (dHLT) is an on-line processing stage whose primary function is to select interesting events that contain distinct physics signals from heavy resonance decays such as J/psi and Gamma particles, amidst unwanted background events. It forms part of the High Level Trigger of the ALICE experiment, whose goal is to reduce the large data rate of about 25 GB/s from the ALICE detectors by an order of magnitude, without loosing interesting physics events. The dHLT has been implemented as a software trigger within a high performance and fault tolerant data transportation framework, which is run on a large cluster of commodity compute nodes. To reach the required processing speeds, the system is built as a concurrent system with a hierarchy of processing steps. The main algorithms perform partial event reconstruction, starting with hit reconstruction on the level of the raw data received from the spectrometer. Then a tracking algorithm finds track candidates from the recon...

  2. High level white noise generator

    International Nuclear Information System (INIS)

    Borkowski, C.J.; Blalock, T.V.

    1979-01-01

    A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application

  3. High level white noise generator

    Science.gov (United States)

    Borkowski, Casimer J.; Blalock, Theron V.

    1979-01-01

    A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.

  4. Epidemiological investigation of radiological effects in high background radiation areas of Yangjiang, China

    International Nuclear Information System (INIS)

    Wei, Luxin; Zha, Yongru; Tao, Zufan; He, Weihui; Chen, Deqing; Yuan, Yongling

    1990-01-01

    The purpose of this investigation is to provide some information for providing whether any detrimental effects exist in a large population whose families have been continuously exposed to a low dose rate radiation. Two areas in Yangjiang Country, characterized by high background radiation (HBR) with environmental gamma exposure, large population size and long-term inhabitants, were selected for evaluation of late effects of HBR. The areas with normal radiation background close to the Yangjiang Country were selected as control areas. Up to 1986 approximately one million person-years in each area in both HBR and control areas have been observed. No increase of cancer mortality was found in the HBR areas; on the contrary, cancer mortality tended to be lower in the HBR areas than the control areas. The prevalence of hereditary diseases and congenital defects was similar in both HBR and control areas, but the frequency of Down's syndrome was higher in the HBR areas (through within the normal range) than the control areas. A possible explanation is the difference of age of maternity between the HBR and control areas, and the extremely low frequency in the control areas. Possible factors influencing the incidence of mutationbased diseases were comparable in the HBR and control groups. However, the cultural and educational levels were somewhat different, probably affecting health status and family planning. It is likely that there may be a dose threshold for cancer incidence, but this remains to be determined by further research. (N.K.)

  5. Influence of NORMs on the natural background radiation level in petroleum-producing countries

    International Nuclear Information System (INIS)

    Ali, F.M.

    2002-01-01

    Naturally occurring radioactive materials (NORMs) which are found in the Earth's crust, in the form of 226 Ra and 228 Ra and their associated radionuclides, are brought to the surface of the ground as a result of oil production processes, and are known under the name of technologically enhanced natural radioactivity (TENR). These represent a potential hazard of significant scale. 226 Ra, an α emitter, represents a potential internal radiation exposure hazard to both workers and members of the public, arising from the inhalation and ingestion of the dust produced during cleaning operations for the descaling of pipes and separator tanks. In addition to this, a higher than normal background γ exposure rate is to be observed both around and directly at the areas where the mud from the separator tanks and pipe cleaning operations was routinely dumped. Therefore, the aim of this work was to present the data on radiation levels measured in contaminated areas located near to a number of oilfields in Egypt and in Syria. The decontamination processes undertaken and the precautions necessary to ensure elimination of the possible transport mechanisms for contaminated dust into public areas by wind are presented. (orig.)

  6. Modeling Speech Level as a Function of Background Noise Level and Talker-to-Listener Distance for Talkers Wearing Hearing Protection Devices

    Science.gov (United States)

    Bouserhal, Rachel E.; Bockstael, Annelies; MacDonald, Ewen; Falk, Tiago H.; Voix, Jérémie

    2017-01-01

    Purpose: Studying the variations in speech levels with changing background noise level and talker-to-listener distance for talkers wearing hearing protection devices (HPDs) can aid in understanding communication in background noise. Method: Speech was recorded using an intra-aural HPD from 12 different talkers at 5 different distances in 3…

  7. Optimizing High Level Waste Disposal

    International Nuclear Information System (INIS)

    Dirk Gombert

    2005-01-01

    If society is ever to reap the potential benefits of nuclear energy, technologists must close the fuel-cycle completely. A closed cycle equates to a continued supply of fuel and safe reactors, but also reliable and comprehensive closure of waste issues. High level waste (HLW) disposal in borosilicate glass (BSG) is based on 1970s era evaluations. This host matrix is very adaptable to sequestering a wide variety of radionuclides found in raffinates from spent fuel reprocessing. However, it is now known that the current system is far from optimal for disposal of the diverse HLW streams, and proven alternatives are available to reduce costs by billions of dollars. The basis for HLW disposal should be reassessed to consider extensive waste form and process technology research and development efforts, which have been conducted by the United States Department of Energy (USDOE), international agencies and the private sector. Matching the waste form to the waste chemistry and using currently available technology could increase the waste content in waste forms to 50% or more and double processing rates. Optimization of the HLW disposal system would accelerate HLW disposition and increase repository capacity. This does not necessarily require developing new waste forms, the emphasis should be on qualifying existing matrices to demonstrate protection equal to or better than the baseline glass performance. Also, this proposed effort does not necessarily require developing new technology concepts. The emphasis is on demonstrating existing technology that is clearly better (reliability, productivity, cost) than current technology, and justifying its use in future facilities or retrofitted facilities. Higher waste processing and disposal efficiency can be realized by performing the engineering analyses and trade-studies necessary to select the most efficient methods for processing the full spectrum of wastes across the nuclear complex. This paper will describe technologies being

  8. Ingestion of polonium ((210)Po) via dietary sources in high background radiation areas of south India.

    Science.gov (United States)

    Arunachalam, Kantha Deivi; Baskaran, Kamesh Viswanathan; Rao, D D; Sathyapriya, R; Annamalai, Sathesh Kumar; Kuruva, Jaya Krishna; Hari, Shanmugamsundaram

    2014-10-01

    To study the distribution of Polonium ((210)Po) activity in dietary sources in the high background radiation zone of Puttetti in southern Tamil Nadu. (210)Po was analyzed in the food materials consumed by the male and female individual representatives living in the high background areas by 24-h Duplicate Diet Study (DDS) and Market Basket Study (MBS). The MBS was performed by collecting the food samples such as, cereals, fruits, leafy vegetables, roots and tubers, other vegetables, fish, meat and milk grown in the high background radiation zone of southern Tamil Nadu as a part of baseline study in this region. The DDS was done by collecting the food materials consumed including the beverages in 24 h from different age groups of male and female individuals living in the village of Puttetti. The intake and ingestion dose of the radionuclide (210)Po was estimated. The average concentration of (210)Po in DDS (n = 33) was found to be 74 mBq.kg(- 1) of fresh weight. The MBS was collected based on food consumption representing more than 85-95% of annual supply, and were divided into eight food groups. The average concentration of (210)Po in the eight food groups namely leafy vegetables was 2176 mBq.kg(- 1) (n = 3), vegetables 55 mBq.kg(- 1) (n = 10), roots and tubers 251 mBq.kg(- 1) (n = 4), fruits 65 mBq.kg(- 1) (n = 5), fish 345 mBq.kg(- 1) (n = 2), meat food 117 mBq.kg(- 1) (n = 3), milk 20 mBq.kg(- 1) (n = 1) and cereal 290 (n = 1) mBq.kg(- 1) of fresh weight, respectively. The annual intake and ingestion dose due to (210)Po was estimated by DDS and MBS in adults, adolescents and children. The overall results showed that the MBS was moderately higher than the DDS in all age groups. Moreover, a DDS approach may even be more realistic, as cooked foodstuffs are used for dietary exposure assessment. The study confirms that the current levels of (210)Po do not pose a significant radiological risk to the local inhabitants.

  9. Geostatistics as a tool to improve the natural background level definition: An application in groundwater.

    Science.gov (United States)

    Dalla Libera, Nico; Fabbri, Paolo; Mason, Leonardo; Piccinini, Leonardo; Pola, Marco

    2017-11-15

    The Natural Background Level (NBL), suggested by UE BRIDGE project, is suited for spatially distributed datasets providing a regional value that could be higher than the Threshold Value (TV) set by every country. In hydro-geochemically dis-homogeneous areas, the use of a unique regional NBL, higher than TV, could arise problems to distinguish between natural occurrences and anthropogenic contaminant sources. Hence, the goal of this study is to improve the NBL definition employing a geostatistical approach, which reconstructs the contaminant spatial structure accounting geochemical and hydrogeological relationships. This integrated mapping is fundamental to evaluate the contaminant's distribution impact on the NBL, giving indications to improve it. We decided to test this method on the Drainage Basin of Venice Lagoon (DBVL, NE Italy), where the existing NBL is seven times higher than the TV. This area is notoriously affected by naturally occurring arsenic contamination. An available geochemical dataset collected by 50 piezometers was used to reconstruct the spatial distribution of arsenic in the densely populated area of the DBVL. A cokriging approach was applied exploiting the geochemical relationships among As, Fe and NH4+. The obtained spatial predictions of arsenic concentrations were divided into three different zones: i) areas with an As concentration lower than the TV, ii) areas with an As concentration between the TV and the median of the values higher than the TV, and iii) areas with an As concentration higher than the median. Following the BRIDGE suggestions, where enough samples were available, the 90th percentile for each zone was calculated to obtain a local NBL (LNBL). Differently from the original NBL, this local value gives more detailed water quality information accounting the hydrogeological and geochemical setting, and contaminant spatial variation. Hence, the LNBL could give more indications about the distinction between natural occurrence and

  10. α-rays induced background in ultra low level counting with Ge spectrometers

    International Nuclear Information System (INIS)

    Hubert, P.; Dassie, D.; Larrieu, P.; Leccia, F.; Mennrath, P.; Chevallier, J.; Chevallier, A.; Morales, A.; Nunez-Lagoz, R.; Morales, J.; Villar, J.A.

    1986-01-01

    Background spectra of several spectrometers have been recorded in a deep underground laboratory located in the Frejus tunnel. The results show that an α ray induced background from the 210 Pb decay is observed. A possible explanation could be related to the adsorption of the Rn gas on the surfaces of the Ge crystal and/or other parts during the assembly of the spectrometer. (orig.)

  11. Precision tracking at high background rates with the ATLAS muon spectrometer

    CERN Document Server

    Hertenberger, Ralf; The ATLAS collaboration

    2012-01-01

    Since start of data taking the ATLAS muon spectrometer performs according to specification. End of this decade after the luminosity upgrade of LHC by a factor of ten the proportionally increasing background rates require the replacement of the detectors in the most forward part of the muon spectrometer to ensure high quality muon triggering and tracking at background hit rates of up to 15,kHz/cm$^2$. Square meter sized micromegas detectors together with improved thin gap trigger detectors are suggested as replacement. Micromegas detectors are intrinsically high rate capable. A single hit spatial resolution below 40,$mu$m has been shown for 250,$mu$m anode strip pitch and perpendicular incidence of high energy muons or pions. The ongoing development of large micromegas structures and their investigation under non-perpendicular incidence or in high background environments requires precise and reliable monitoring of muon tracks. A muon telescope consisting of six small micromegas works reliably and is presently ...

  12. Measurement of background gamma radioactivity level in Rize and its towns

    International Nuclear Information System (INIS)

    Keser, R.; Dizman, S.; Goeruer, F. K.; Okumusoglu, N. T.

    2006-01-01

    Naturally occurring primordial radionuclides are present in various degrees in all media in the environment, including the human body itself. Only the radionuclides with half-lives comparable to the age of the earth, and their decay products and radioisotopes such as 1 37Cs, 9 0Sr from man made sources such as Chernobyl accident and nuclear tests are present in the environment. The irradiation of the human body from external sources is mainly by gamma radiation from radionuclides in the 2 38U and 2 32Th series such as 2 14 Pb, 2 28Ac and from 4 0K and 1 37Cs. The aim of this study was to measure background γ-ray activities and distributions of natural radionuclides in selected regions in Rize, such as Iyidere, Derepazari, Cayeli, Pazar, Ardesen, Findikli towns which are on the coast of Black Sea and from inland towns Ikizdere, Kalkandere, Camlihemsin and Hemsin. The geographical distribution of natural radionuclides 2 14Bi , 2 28Ac 4 0K and 1 37Cs their γ-ray activities and respective annual effective dose rates were determined using a high performance hand-held Canberra Inspector 1000 spectrometer for all of regions at various times with a week period. Surface gamma measurements (cps) and dose rate measurements show different values at different regions. The outdoor terrestrial gamma annual effective doses in air at 1 m above ground fluctuates between 0.16 to 0.55 mSv/y with an average of 0.38 mSv/y . The gamma dose rate in air due to natural radionuclides measured in Rize district in the present study have been found to be lower than the global average 0.48 mSv/y

  13. Attitudes, Values and Background of High School Journalists Compared with the Media Elite.

    Science.gov (United States)

    Johnson, Sammye

    To compare attitudes, values, and background of high school journalists with those of the media elite (journalists already working in the media), a survey was administered to 132 public and private high school students attending the Trinity University Journalism Institute during June 5-9, 1983. These students were the editors of their newspapers,…

  14. Association Between Educational Level and Risk of Cancer in HIV-infected Individuals and the Background Population

    DEFF Research Database (Denmark)

    Legarth, Rebecca; Omland, Lars H; Dalton, Susanne O

    2015-01-01

    -infected individuals diagnosed (without intravenous drug abuse or hepatitis C infection) (n = 3205), and a background population cohort matched by age, gender, and country of birth (n = 22 435) were analyzed. Educational level (low or high) and cancer events were identified in Danish national registers. Cumulative...... incidences, incidence rate ratios (IRRs), and survival using Kaplan-Meier methods were estimated. RESULTS: Low educational level was associated with increased risk of cancer among HIV-infected individuals compared to population controls: all (adjusted-IRRs: 1.4 [95% confidence interval {CI}, 1.1-1.7] vs 1.......1 [95% CI, .9-1.2]), tobacco- and alcohol-related (2.1 [95% CI, 1.3-3.4] vs 1.3 [95% CI, 1.1-1.6]), and other (1.7 [95% CI, 1.1-2.8] vs 0.9 [95% CI, .7-1.0]). Educational level was not associated with infection-related or ill-defined cancers. One-year-survival was not associated with educational level...

  15. Investigation on Down's syndrome in the children living in high background radiation area

    International Nuclear Information System (INIS)

    Zha Yongru

    1989-01-01

    After the survey in 1975 and 1979 of Down's syndrome in the children living in high background radiation area, we made a follow-up investigation in 1985 and 1986. All the obtained data are analysed. 25258 children in high background radiation area were examined and 22 children with Down's syndrome were identified, the morbidity rate being 0.87%. 21837 children in control area were examined and four children with Down's syndrome were identified, the morbidity being 0.18%. There was a statistically significant difference between the two groups. It was noted that the occurrence of Down's syndrome was related to the maternal age but there was no evidence suggesting a close relationship between high background radiation and the development of Down's syndrome

  16. Beam size measurement at high radiation levels

    International Nuclear Information System (INIS)

    Decker, F.J.

    1991-05-01

    At the end of the Stanford Linear Accelerator the high energy electron and positron beams are quite small. Beam sizes below 100 μm (σ) as well as the transverse distribution, especially tails, have to be determined. Fluorescent screens observed by TV cameras provide a quick two-dimensional picture, which can be analyzed by digitization. For running the SLAC Linear Collider (SLC) with low backgrounds at the interaction point, collimators are installed at the end of the linac. This causes a high radiation level so that the nearby cameras die within two weeks and so-called ''radiation hard'' cameras within two months. Therefore an optical system has been built, which guides a 5 mm wide picture with a resolution of about 30 μm over a distance of 12 m to an accessible region. The overall resolution is limited by the screen thickness, optical diffraction and the line resolution of the camera. Vibration, chromatic effects or air fluctuations play a much less important role. The pictures are colored to get fast information about the beam current, size and tails. Beside the emittance, more information about the tail size and betatron phase is obtained by using four screens. This will help to develop tail compensation schemes to decrease the emittance growth in the linac at high currents. 4 refs., 2 figs

  17. Radiation levels at the boundaries of the Frascati center and natural background

    International Nuclear Information System (INIS)

    Lucci, F.; Pelliccioni, M.

    1975-01-01

    The results of dosimetric controls carried out with thermoluminescent dosimeters along the boundaries of the Frascati Center since 1969 are presented. The average yearly exposure observed during the period 1969-1974 is 206mR/y, while no significant tendency is evident. In particular neither effects of accelerator shutdowns nor seasonal ones are noticed. The measurements at the boundary are also compared with measurements of natural background carried out near Frascati and in Rome, Thus we can estimate that the machine contribution to the total dose along the boundaries is equal to a small fraction of either the natural background or the general population dose limit [fr

  18. Cosmological implications of the MAXIMA-1 high-resolution cosmic microwave background anisotropy measurement

    International Nuclear Information System (INIS)

    Stompor, R.; Abroe, M.; Ade, P.; Balbi, A.; Barbosa, D.; Bock, J.; Borrill, J.; Boscaleri, A.; de Bernardis, P.; Ferreira, P.G.; Hanany, S.; Hristov, V.; Jaffe, A.H.; Lee, A.T.; Pascale, E.; Rabii, B.; Richards, P.L.; Smoot, G.F.; Winant, C.D.; Wu, J.H.P.

    2001-01-01

    We discuss the cosmological implications of the new constraints on the power spectrum of the cosmic microwave background (CMB) anisotropy derived from a new high-resolution analysis of the MAXIMA-1 measurement. The power spectrum indicates excess power at lsimilar to 860 over the average level of power at 411 less than or equal to l less than or equal to 785. This excess is statistically significant at the similar to 95 percent confidence level. Its position coincides with that of the third acoustic peak, as predicted by generic inflationary models selected to fit the first acoustic peak as observed in the data. The height of the excess power agrees with the predictions of a family of inflationary models with cosmological parameters that are fixed to fit the CMB data previously provided by BOOMERANG-LDB and MAXIMA-1 experiments. Our results therefore lend support for inflationary models and more generally for the dominance of adiabatic coherent perturbations in the structure formation of the universe. At the same time, they seem to disfavor a large variety of the nonstandard (but inflation-based) models that have been proposed to improve the quality of fits to the CMB data and the consistency with other cosmological observables. Within standard inflationary models, our results combined with the COBE/Differential Microwave Radiometer data give best-fit values and 95 percent confidence limits for the baryon density, Omega (b)h(2)similar or equal to 0.033 +/- 0.013, and the total density, Omega =0.9(-0.16)(+0.18). The primordial spectrum slope (n(s)) and the optical depth to the last scattering surface (tau (c)) are found to be degenerate and to obey the relation n(s) similar or equal to (0.99 +/- 0.14) + 0.46tau (c), for tau (c) less than or equal to 0.5 (all at 95 percent confidence levels)

  19. Cytogenetic findings from inhabitants of different ages in high background radiation areas of Yangjiang

    International Nuclear Information System (INIS)

    Chen Deqing; Yao Suyan; Zhang Chaoyang

    1997-01-01

    Objective: To explore the relationship between high background radiation and injurious effect on inhabitants. Method: Peripheral blood samples were collected from the inhabitants of 10, 40, 55 and 70 years old in high background radiation areas (HBRA) of Yangjiang, Chromosome preparations were carried out with conventional whole-blood microculture. Results: The percentage of dicentric chromosome with fragments in inhabitants of HBRA was significantly higher than that in control areas (CA) (0.469% vs. 0.315%, P<0.01), and there was an increase in the aberration frequencies with age (or accumulated doses). Conclusion: Chromosome aberration is an extremely sensitive indicator of radiation damage and a good radio-biodosimeter

  20. Investigation and analysis of etiology of down's syndrome in children of high background radiation area

    International Nuclear Information System (INIS)

    Zha Yongru

    1985-01-01

    In order to find out what caused the differences in incidences of Down's syndrome between the children in high background radiation area and those in control area, investigation and analysis were carried ou in 5 aspects based on the original data and the information from the previous survey. These are: the incidences of congenital malformations in normal areas, the age distribution of children examined, the maternal age, the dates of birth of afflicted children, and the radiation exposure of mothers. The results suggested that the higher incidence of Down's syndrome in high background area might be related to the materal age. Further studies are needed to arrive at a conclusion

  1. Design and environmental applications of an ultra-low-background, high-efficiency intrinsic Ge gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Wogman, N.A.

    1981-04-01

    A coincidence shielded intrinsic Ge gamma-ray spectrometer incorporating a 25% efficient, high resolution coaxial diode inside a 30 cm diameter NaI(Tl) shield is described. System design eliminates the major cause of background and minimizes cosmic-ray created background events through the use of electronic means. The system provides a peak-to-Compton ratio of greater than 1000 to 1 for 137 Cs and high sensitivity for both low and high level radionuclide measurements. At 3 MeV the background is 0.000058 counts per minute per keV. At 1 MeV it is 0.00048 counts per minute per keV, and at 0.5 MeV it is 0.0045 counts per minute per keV. Traces of primordial radionuclides create background events such as at 2.614 MeV (0.016 counts per minute total peak area), at 2.448 MeV (0.0058 counts per minute per total peak area), and at 2.204 MeV (0.023 counts per minute per total peak area). The system is discussed with respect to its background design, methods to improve its design, and its application to measurements of neutron activated and environmental materials problems

  2. Detection of admittivity anomaly on high-contrast heterogeneous backgrounds using frequency difference EIT.

    Science.gov (United States)

    Jang, J; Seo, J K

    2015-06-01

    This paper describes a multiple background subtraction method in frequency difference electrical impedance tomography (fdEIT) to detect an admittivity anomaly from a high-contrast background conductivity distribution. The proposed method expands the use of the conventional weighted frequency difference EIT method, which has been used limitedly to detect admittivity anomalies in a roughly homogeneous background. The proposed method can be viewed as multiple weighted difference imaging in fdEIT. Although the spatial resolutions of the output images by fdEIT are very low due to the inherent ill-posedness, numerical simulations and phantom experiments of the proposed method demonstrate its feasibility to detect anomalies. It has potential application in stroke detection in a head model, which is highly heterogeneous due to the skull.

  3. Preliminary indoor thoron measurements in high radiation background area of southeastern coastal Orissa (India)

    International Nuclear Information System (INIS)

    Ramola, R. C.; Prasad, G.; Gusain, G. S.; Rautela, B. S.; Choubey, V. M.; Vidya Sagar, D.; Tokonami, S.; Sorimachi, A.; Sahoo, S. K.; Janik, M.; Ishikawa, T.

    2010-01-01

    This paper presents the preliminary results of radon and thoron measurements in the houses of Chhatrapur area of southeastern coast of Orissa (India). This area is one of the high radiation background radiation areas in India, which consists of monazite sand as the source of thoron. Both active and passive methods were employed for the measurements. Radon and thoron concentrations were measured in the houses of Chhatrapur area using twin cup radon dosemeters, RAD7 and radon-thoron discriminative detector (Raduet). Thoron progeny concentration was also measured in the houses using deposition rate measurements. Radon and thoron concentrations in the houses of study area were found to vary from 8 to 47 Bq m -3 and the below detection level to 77 Bq m -3 , respectively. While thoron progeny concentration in these houses ranges between 0.17 and 4.24 Bq m -3 , preliminary investigation shows that the thoron concentration is higher than radon concentration in the houses of the study area. The thoron progeny concentration was found to be comparatively higher, which forms a base for further study in the area. The comparison between the results of various techniques is presented in this paper. (authors)

  4. Preliminary indoor thoron measurements in high radiation background area of southeastern coastal Orissa (India)

    Energy Technology Data Exchange (ETDEWEB)

    Ramola, R C; Prasad, G; Gusain, G S; Rautela, B S [Dept. of Physics, H.N.B. Garhwal Univ., Badshahi Thaul, Tehri Garhwal 249 199 (India); Choubey, V M [Wadia Inst. of Himalayan Geology, Dehradun 248 001 (India); Vidya Sagar, D [Health Physics Unit (EAD, BARC), IRE, OSCOM, Matikhalo, Dt. Ganjam, Orissa 761 045 (India); Tokonami, S; Sorimachi, A; Sahoo, S K; Janik, M; Ishikawa, T [National Inst. of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263 8555 (Japan)

    2010-07-01

    This paper presents the preliminary results of radon and thoron measurements in the houses of Chhatrapur area of southeastern coast of Orissa (India). This area is one of the high radiation background radiation areas in India, which consists of monazite sand as the source of thoron. Both active and passive methods were employed for the measurements. Radon and thoron concentrations were measured in the houses of Chhatrapur area using twin cup radon dosemeters, RAD7 and radon-thoron discriminative detector (Raduet). Thoron progeny concentration was also measured in the houses using deposition rate measurements. Radon and thoron concentrations in the houses of study area were found to vary from 8 to 47 Bq m{sup -3} and the below detection level to 77 Bq m{sup -3}, respectively. While thoron progeny concentration in these houses ranges between 0.17 and 4.24 Bq m{sup -3}, preliminary investigation shows that the thoron concentration is higher than radon concentration in the houses of the study area. The thoron progeny concentration was found to be comparatively higher, which forms a base for further study in the area. The comparison between the results of various techniques is presented in this paper. (authors)

  5. Hawkes process model with a time-dependent background rate and its application to high-frequency financial data.

    Science.gov (United States)

    Omi, Takahiro; Hirata, Yoshito; Aihara, Kazuyuki

    2017-07-01

    A Hawkes process model with a time-varying background rate is developed for analyzing the high-frequency financial data. In our model, the logarithm of the background rate is modeled by a linear model with a relatively large number of variable-width basis functions, and the parameters are estimated by a Bayesian method. Our model can capture not only the slow time variation, such as in the intraday seasonality, but also the rapid one, which follows a macroeconomic news announcement. By analyzing the tick data of the Nikkei 225 mini, we find that (i) our model is better fitted to the data than the Hawkes models with a constant background rate or a slowly varying background rate, which have been commonly used in the field of quantitative finance; (ii) the improvement in the goodness-of-fit to the data by our model is significant especially for sessions where considerable fluctuation of the background rate is present; and (iii) our model is statistically consistent with the data. The branching ratio, which quantifies the level of the endogeneity of markets, estimated by our model is 0.41, suggesting the relative importance of exogenous factors in the market dynamics. We also demonstrate that it is critically important to appropriately model the time-dependent background rate for the branching ratio estimation.

  6. Hawkes process model with a time-dependent background rate and its application to high-frequency financial data

    Science.gov (United States)

    Omi, Takahiro; Hirata, Yoshito; Aihara, Kazuyuki

    2017-07-01

    A Hawkes process model with a time-varying background rate is developed for analyzing the high-frequency financial data. In our model, the logarithm of the background rate is modeled by a linear model with a relatively large number of variable-width basis functions, and the parameters are estimated by a Bayesian method. Our model can capture not only the slow time variation, such as in the intraday seasonality, but also the rapid one, which follows a macroeconomic news announcement. By analyzing the tick data of the Nikkei 225 mini, we find that (i) our model is better fitted to the data than the Hawkes models with a constant background rate or a slowly varying background rate, which have been commonly used in the field of quantitative finance; (ii) the improvement in the goodness-of-fit to the data by our model is significant especially for sessions where considerable fluctuation of the background rate is present; and (iii) our model is statistically consistent with the data. The branching ratio, which quantifies the level of the endogeneity of markets, estimated by our model is 0.41, suggesting the relative importance of exogenous factors in the market dynamics. We also demonstrate that it is critically important to appropriately model the time-dependent background rate for the branching ratio estimation.

  7. PCA-based approach for subtracting thermal background emission in high-contrast imaging data

    Science.gov (United States)

    Hunziker, S.; Quanz, S. P.; Amara, A.; Meyer, M. R.

    2018-03-01

    Aims.Ground-based observations at thermal infrared wavelengths suffer from large background radiation due to the sky, telescope and warm surfaces in the instrument. This significantly limits the sensitivity of ground-based observations at wavelengths longer than 3 μm. The main purpose of this work is to analyse this background emission in infrared high-contrast imaging data as illustrative of the problem, show how it can be modelled and subtracted and demonstrate that it can improve the detection of faint sources, such as exoplanets. Methods: We used principal component analysis (PCA) to model and subtract the thermal background emission in three archival high-contrast angular differential imaging datasets in the M' and L' filter. We used an M' dataset of β Pic to describe in detail how the algorithm works and explain how it can be applied. The results of the background subtraction are compared to the results from a conventional mean background subtraction scheme applied to the same dataset. Finally, both methods for background subtraction are compared by performing complete data reductions. We analysed the results from the M' dataset of HD 100546 only qualitatively. For the M' band dataset of β Pic and the L' band dataset of HD 169142, which was obtained with an angular groove phase mask vortex vector coronagraph, we also calculated and analysed the achieved signal-to-noise ratio (S/N). Results: We show that applying PCA is an effective way to remove spatially and temporarily varying thermal background emission down to close to the background limit. The procedure also proves to be very successful at reconstructing the background that is hidden behind the point spread function. In the complete data reductions, we find at least qualitative improvements for HD 100546 and HD 169142, however, we fail to find a significant increase in S/N of β Pic b. We discuss these findings and argue that in particular datasets with strongly varying observing conditions or

  8. Further investigation on chromosome aberrations in lymphocytes of inhabitants in high background radiation area in Yangjiang

    International Nuclear Information System (INIS)

    Chen Deqing; Zhang Chaoyang; Yao Suyan

    1985-01-01

    Blood samples were taken from 122 healthy secondary school students at the age of 15 to 16 living in a high background radiation region and from 99 controls, All subjects from both areas had lived there since their births; they were non-smokers and without history of exposure to medical X-rays. The youngsters of 15 to 16 years old who were native-born and grew up in the high background radiation area received approximately 3.5 rad more cumulative γ-ray exposure than those in the control area. For each individual 200 M-1 cells were analysed. The frequency of chromosome aberrations in the high background group was 0.47/100 cells, while that in the control group was 0.33/100 cells, the diffrence being statistically significant. The frequencies of acentrics (fragment, acentric ring and minute), dicentrics and stable aberrations (inversion and translocation) were 0.41, 0.021 and 0.045/100 cells respectively in the high background group, and 0.30, 0.020 and 0.005/100 cells respectively in the control group. Only the difference of stable aberrations between the two groups was significant

  9. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    International Nuclear Information System (INIS)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner; Simon, Steven L; Wojcik, Andrzej; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2009-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222 Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  10. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Energy Technology Data Exchange (ETDEWEB)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna (Austria); Simon, Steven L [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD (United States); Wojcik, Andrzej [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Cardis, Elisabeth [Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM-Hospital del Mar) and CIBER Epidemiologia y Salud Publica - CIBERESP, Barcelona (Spain); Laurier, Dominique; Tirmarche, Margot [Radiobiology and Epidemiology Department, Radiological and Human Health Division, Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses (France); Hayata, Isamu [National Institute of Radiological Sciences, Chiba (Japan)], E-mail: jhendry2002uk@yahoo.com

    2009-06-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of {sup 222}Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  11. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Science.gov (United States)

    Hendry, Jolyon H; Simon, Steven L; Wojcik, Andrzej; Sohrabi, Mehdi; Burkart, Werner; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2014-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case–control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case–control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors. PMID:19454802

  12. Mechanism of high-temperature background of internal friction in metals

    International Nuclear Information System (INIS)

    Shapoval, B.I.; Arzhavitin, V.M.

    1988-01-01

    Data of theoretical and experimental studies on energy dissipation in vibrating metal at small amplitudes and elevated temperatures (high temperature background of internal friction) are generalized and systematized. Evolution of knowledge of the background as a phenomenon influenced mainly by crystal structure defects - their form, quantity, mobility and interaction is followed. Considered is a wide range of investigated metal states and measurement conditions, and interrelations with other characteristics, for instance, strength ones. On the basis of the data obtained by authors and other investigations a concept of an additional third stage of the background increase with the temperature - the stage of deviation from exponential dependence at premelting point, is introduced. 107 refs.; 32 figs.; 3 tabs

  13. Level of natural background radiation and dose to population in Heilongjiang province

    International Nuclear Information System (INIS)

    Liang Yicheng; Wang Lu; He Yongjiang

    1992-01-01

    The natural background radiation in Heilongjiang Province was measured and the population dose was estimated. The results showed that the population-weighted average values of the absorbed dose rate in air from cosmic ray ionization were 3.3 ± 10 -8 Gy·h -1 outdoors and 3.0 x 10 -8 Gy·h -1 indoors. The average values of radon in air were 11.3 Bq·m -3 outdoors and 20.8 Bq·m -3 indoors. The average concentrations of natural radionuclides U, Th, 226 Ra, and 40 K were 6.1 x 10 -2 , 1.1 x 10 -2 , 8.4 x 10 -2 , and 68.9 Bq·kg -1 respectively in food, and 4.8 x 10 -2 , 2.0 x 10 -4 , 1.2 x 10 -2 and 4.6 x 10 -2 Bq·L -1 respectively in drinking water. The total annual individual average effective dose equivalents from natural background radiation were about 2200 μSv. Among them the contributions of cosmic rays, terrestrial radiation, radon and thoron daughters exposure in air, internal exposure within the body were about 320, 630, 860, and 390 μSv, respectively

  14. Level of natural background radiation and dose to population in Jilin Province

    International Nuclear Information System (INIS)

    Li Wanxi; Chen Huiying; Ju Cuixiang; Li Fulin; Li Xianggao

    1994-01-01

    The natural background radiation in Jilin Province was measured and the population dose was estimated. The results showed that the population-weighted average value of the absorbed dose rate in air from cosmic ray ionization was 3.2 x 10 -8 Gy·h -1 . The average absorbed dose rates in air from terrestrial γ radiation were 7.7 x 10 -8 Gy·h -1 outdoors and 9.8 x 10 -8 Gy·h -1 indoors. The average values of radon in air were 8.7 Bq·m -3 outdoors and 5.8 Bq·m -3 indoors. The average concentration of natural radionuclides U, Th, 226 Ra, and 40 K were 3.7 x 10 -2 , 2.4 x 10 -2 , 14.7 x 10 -2 and 81.5 Bq·kg -1 in food, and 2.3, 0.1, 1.1 and 0.3 Bq·L -1 in drinking water, respectively. The total annual individual average effective dose equivalent from natural background radiation was about 1.5 mSv

  15. Level of natural background radiation and dose to population in Zhejiang Province

    International Nuclear Information System (INIS)

    Zhao Yifang; Chen Guopei; Wang Zanxin; Ma Mingqiang

    1994-01-01

    The natural background radiation in Zhejiang Province was measured and the dose to population was estimated. The results showed that the population-weighted average values of the absorbed dose rate in air from cosmic ray ionization were 3.0 x 10 -8 Gy·h -1 outdoors and 2.7 x 10 -8 Gy·h -1 indoors. The average absorbed dose rates in air from terrestrial γ-radiation were 9.1 x 10 -8 Gy·h -1 outdoors and 14.9 x 10 -8 Gy·h -1 indoors. The average values of radon in air were 17.2 Bq· -3 indoors and 12.7 Bq·m -8 outdoors. The contents of natural radionuclides in food and water were measured. The total annual individual average effective dose from natural background radiation was about 2.0 mSv. The contributions of cosmic rays, terrestrial radiation radon and thoron daughters exposure in air and internal exposure within the body were about 0.24, 0.77, 0.67 and 0.35 mSv, respectively. The annual collective effective dose to population in the province was estimated to be 8.5 x 10 4 man Sv·a -1

  16. Background information on sources of low-level radionuclide emissions to air

    International Nuclear Information System (INIS)

    Corbit, C.D.; Herrington, W.N.; Higby, D.P.; Stout, L.A.; Corley, J.P.

    1983-09-01

    This report provides a general description and reported emissions for eight low-level radioactive source categories, including facilties that are licensed by the Nuclear Regulatory Commission (NRC) and Agreement States, and non-Department of Energy (DOE) federal facilities. The eight categories of low-level radioactive source facilities covered by this report are: research and test reactors, accelerators, the radiopharmaceutical industry, source manufacturers, medical facilities, laboratories, naval shipyards, and low-level commercial waste disposal sites. Under each category five elements are addressed: a general description, a facility and process description, the emission control systems, a site description, and the radionuclides released to air (from routine operations)

  17. Background information on sources of low-level radionuclide emissions to air

    Energy Technology Data Exchange (ETDEWEB)

    Corbit, C.D.; Herrington, W.N.; Higby, D.P.; Stout, L.A.; Corley, J.P.

    1983-09-01

    This report provides a general description and reported emissions for eight low-level radioactive source categories, including facilties that are licensed by the Nuclear Regulatory Commission (NRC) and Agreement States, and non-Department of Energy (DOE) federal facilities. The eight categories of low-level radioactive source facilities covered by this report are: research and test reactors, accelerators, the radiopharmaceutical industry, source manufacturers, medical facilities, laboratories, naval shipyards, and low-level commercial waste disposal sites. Under each category five elements are addressed: a general description, a facility and process description, the emission control systems, a site description, and the radionuclides released to air (from routine operations).

  18. Vitrification of high level wastes in France

    International Nuclear Information System (INIS)

    Sombret, C.

    1984-02-01

    A brief historical background of the research and development work conducted in France over 25 years is first presented. Then, the papers deals with the vitrification at (1) the UP1 reprocessing plant (Marcoule) and (2) the UP2 and UP3 reprocessing plants (La Hague). 1) The properties of glass required for high-level radioactive waste vitrification are recalled. The vitrification process and facility of Marcoule are presented. (2) The average characteristics (chemical composition, activity) of LWR fission product solution are given. The glass formulations developed to solidify LWR waste solution must meet the same requirements as those used in the UP1 facility at Marcoule. Three important aspects must be considered with respect to the glass fabrication process: corrosiveness of the molten glass with regard to metals, viscosity of the molten glass, and, volatization during glass fabrication. The glass properties required in view of interim storage and long-term disposal are then largely developed. Two identical vitrification facilities are planned for the site: T7, to process the UP2 throughput, and T7 for the UP3 plant. A prototype unit was built and operated at Marcoule

  19. Low level beta-activity radiometer with compensation of the background

    Energy Technology Data Exchange (ETDEWEB)

    Vankov, I [and others

    1996-12-31

    New type of the low level beta-activity scintillation detector system is developed. The procedure of finding the beta activity and the operation of the recording unit of the radiometer are considered. 3 refs.; 5 figs.

  20. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    International Nuclear Information System (INIS)

    Molinari, Antonio; Guadagnini, Laura; Marcaccio, Marco; Guadagnini, Alberto

    2012-01-01

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH 4 , B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia–Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH 4 and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring protocols could

  1. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, Antonio, E-mail: ant.molinari2002@libero.it [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Guadagnini, Laura [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Marcaccio, Marco [ARPA Emilia-Romagna, Direzione Tecnica, Largo Caduti del Lavoro, 6-40122 Bologna (Italy); Guadagnini, Alberto [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy)

    2012-05-15

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH{sub 4}, B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia-Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH{sub 4} and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring

  2. Fluctuations in radiation backgrounds at high redshift and the first stars

    Science.gov (United States)

    Holzbauer, Lauren Nicole

    The first stars to light up our universe are as yet unseen, but there have been many attempts to elucidate their properties. The characteristics of these stars (`Population/Pop III' stars) that we do know lie mostly within theory; they formed out of metal-free hydrogen and helium gas contained in dark matter minihalos at redshifts z 20-30. The extent to which Pop III star formation reached into later times is unknown. Current and near future instruments are incapable of resolving individual Pop III stars. Consequently, astronomers must devise creative means with which to indirectly predict and measure and their properties. In this thesis, we will investigate a few of those means. We use a new method to model fluctuations of the Lyman-Werner (LW) and Lyman-alpha radiation backgrounds at high redshift. At these early epochs the backgrounds are symptoms of a universe newly lit with its first stars. LW photons (11.5-13.6 eV) are of particular interest because they dissociate molecular hydrogen, the primary coolant in the first minihalos that is necessary for star formation. By using a variation of the `halo model', which describes the spatial distribution and clustering of halos, we can efficiently generate power spectra for these backgrounds. Spatial fluctuations in the LW and (indirectly) the Lyman-alpha BG can tell us about the transition from primordial star formation to a more metal-enriched mode that marks the beginning of the second generation of stars in our Universe. The Near Infrared Background (NIRB) has for some time been considered a potential tool with which to indirectly observe the first stars. Ultraviolet (UV) emission from these stars is redshifted into the NIR band, making the NIRB amenable for hunting Pop III stellar signatures. There have been several measurements of the NIRB and subsequent theoretical studies attempting to explain them in recent years. Though controversial, residual levels of the mean NIRB intensity and anisotropies have been

  3. Background information for the development of a low-level waste performance assessment methodology

    International Nuclear Information System (INIS)

    Shipers, L.R.

    1989-12-01

    This document identifies and describes the potential postclosure pathways of radionuclide release, migration, and exposure from low-level radioactive waste disposal facilities. Each pathway identified is composed of a combination of migration pathways (air, surface water, ground water, food chain) and exposure pathways (direct gamma, inhalation, ingestion, surface contact). The pathway identification is based on a review and evaluation of existing information, and not all pathways presented in the document would necessarily be of importance at a given low-level waste disposal site. This document presents pathways associated with undisturbed (ground water, gas generation), naturally disturbed (erosion, bathtubbing, earth creep, frost heave, plant and animal intruder), and inadvertent intruder (construction, agriculture) scenarios of a low-level waste disposal facility. 20 refs., 1 fig

  4. Large Aperture "Photon Bucket" Optical Receiver Performance in High Background Environments

    Science.gov (United States)

    Vilnrotter, Victor A.; Hoppe, D.

    2011-01-01

    The potential development of large aperture groundbased "photon bucket" optical receivers for deep space communications, with acceptable performance even when pointing close to the sun, is receiving considerable attention. Sunlight scattered by the atmosphere becomes significant at micron wavelengths when pointing to a few degrees from the sun, even with the narrowest bandwidth optical filters. In addition, high quality optical apertures in the 10-30 meter range are costly and difficult to build with accurate surfaces to ensure narrow fields-of-view (FOV). One approach currently under consideration is to polish the aluminum reflector panels of large 34-meter microwave antennas to high reflectance, and accept the relatively large FOV generated by state-of-the-art polished aluminum panels with rms surface accuracies on the order of a few microns, corresponding to several-hundred micro-radian FOV, hence generating centimeter-diameter focused spots at the Cassegrain focus of 34-meter antennas. Assuming pulse-position modulation (PPM) and Poisson-distributed photon-counting detection, a "polished panel" photon-bucket receiver with large FOV will collect hundreds of background photons per PPM slot, along with comparable signal photons due to its large aperture. It is demonstrated that communications performance in terms of PPM symbol-error probability in high-background high-signal environments depends more strongly on signal than on background photons, implying that large increases in background energy can be compensated by a disproportionally small increase in signal energy. This surprising result suggests that large optical apertures with relatively poor surface quality may nevertheless provide acceptable performance for deep-space optical communications, potentially enabling the construction of cost-effective hybrid RF/optical receivers in the future.

  5. Survey of Gamma Dose and Radon Exhalation Rate from Soil Surface of High Background Natural Radiation Areas in Ramsar, Iran

    Directory of Open Access Journals (Sweden)

    Rouhollah Dehghani

    2013-09-01

    Full Text Available Background: Radon is a radioactive gas and the second leading cause of death due to lung cancer after smoking. Ramsar is known for having the highest levels of natural background radiation on earth. Materials and Methods: In this research study, 50 stations of high radioactivity areas of Ramsar were selected in warm season of the year. Then gamma dose and radon exhalation rate were measured.Results: Results showed that gamma dose and radon exhalation rate were in the range of 51-7100 nSv/hr and 9-15370 mBq/m2s, respectively.Conclusion: Compare to the worldwide average 16 mBq/m2s, estimated average annual effective of Radon exhalation rate in the study area is too high.

  6. Motor performance of tongue with a computer-integrated system under different levels of background physical exertion

    Science.gov (United States)

    Huo, Xueliang; Johnson-Long, Ashley N.; Ghovanloo, Maysam; Shinohara, Minoru

    2015-01-01

    The purpose of this study was to compare the motor performance of tongue, using Tongue Drive System, to hand operation for relatively complex tasks under different levels of background physical exertion. Thirteen young able-bodied adults performed tasks that tested the accuracy and variability in tracking a sinusoidal waveform, and the performance in playing two video games that require accurate and rapid movements with cognitive processing using tongue and hand under two levels of background physical exertion. Results show additional background physical activity did not influence rapid and accurate displacement motor performance, but compromised the slow waveform tracking and shooting performances in both hand and tongue. Slow waveform tracking performance by the tongue was compromised with an additional motor or cognitive task, but with an additional motor task only for the hand. Practitioner Summary We investigated the influence of task complexity and background physical exertion on the motor performance of tongue and hand. Results indicate the task performance degrades with an additional concurrent task or physical exertion due to the limited attentional resources available for handling both the motor task and background exertion. PMID:24003900

  7. Determination of an Environmental Background Level of Sr-90 in Urine for the Hanford Bioassay Program

    International Nuclear Information System (INIS)

    Antonio, Cheryl L.; Rivard, James W.

    2009-01-01

    During the decommissioning and maintenance of some of the facilities at the U.S. Department of Energy Hanford Site in Washington State, workers have potential for a 90Sr intake. However, because of worldwide radioactive fallout, 90Sr is present in our environment, and can be detectable in routine urine bioassay samples. It is important for the Hanford Site bioassay program to discern an occupational intake from a non-occupational environmental one. A detailed study of the background 90Sr in the urine of unexposed Hanford workers was performed. A survey of the Hanford Site bioassay database found 128 Hanford workers who were hired between 1997 and 2002 and who had a very low potential for an occupational exposure prior to the baseline strontium urinalysis. Each urinalysis sample represented excretion during an approximate 24-hr period. The arithmetic mean value for the 128 pre-exposure baselines was 3.6 ± 5.1 mBq d-1. The 90Sr activities in urine varied from -12 to 20 mBq. The 99th percentile result was 16.4 mBqd-1, which was interpreted to mean that 1% of Hanford workers not occupationally exposed to strontium might exceed 16.4 mBq d-1.

  8. Down's syndrome and related abnormalities in an area of high background radiation in coastal Kerala

    International Nuclear Information System (INIS)

    Kochupillai, N.; Verma, I.C.; Grewal, M.S.; Ramalingaswami, V.

    1976-01-01

    It is stated that in a coastal area of Kerala, Southern India, the background radiation is between 1500 and 3000 mR/yr, this being due to the presence of Th-containing monazite mineral in the soil. During an epidemiological study of modular lesions of the thyroid in this area an apparently high prevalence of Down's syndrome and other forms of severe mental retardation was observed. A house-to-house survey of relevant abnormalities in this area was made, and also in a comparable control area without high background radiation. The frequency of chromosome aberrations in a sample of the population in the study and control areas was also investigated. The observations support the view that radiation induces genetic anomalies occur with above average frequency in the population living in the area with high background radiation. Only gross abnormalities evident in clinical examination were recorded. The study and control populations were similar in age and sex structure and general sociologic conditions. Severe mental retardation was the commonest abnormality encountered, and 85% of the abnormalities detected in the study population were genetic in origin, compared with 56% in the control population. Prevalence of Down's syndrome was 0.93 per 1000 in the study population. (U.K.)

  9. Statistical methods for determination of background levels for naturally occuring radionuclides in soil at a RCRA facility

    International Nuclear Information System (INIS)

    Guha, S.; Taylor, J.H.

    1996-01-01

    It is critical that summary statistics on background data, or background levels, be computed based on standardized and defensible statistical methods because background levels are frequently used in subsequent analyses and comparisons performed by separate analysts over time. The final background for naturally occurring radionuclide concentrations in soil at a RCRA facility, and the associated statistical methods used to estimate these concentrations, are presented. The primary objective is to describe, via a case study, the statistical methods used to estimate 95% upper tolerance limits (UTL) on radionuclide background soil data sets. A 95% UTL on background samples can be used as a screening level concentration in the absence of definitive soil cleanup criteria for naturally occurring radionuclides. The statistical methods are based exclusively on EPA guidance. This paper includes an introduction, a discussion of the analytical results for the radionuclides and a detailed description of the statistical analyses leading to the determination of 95% UTLs. Soil concentrations reported are based on validated data. Data sets are categorized as surficial soil; samples collected at depths from zero to one-half foot; and deep soil, samples collected from 3 to 5 feet. These data sets were tested for statistical outliers and underlying distributions were determined by using the chi-squared test for goodness-of-fit. UTLs for the data sets were then computed based on the percentage of non-detects and the appropriate best-fit distribution (lognormal, normal, or non-parametric). For data sets containing greater than approximately 50% nondetects, nonparametric UTLs were computed

  10. High-level language computer architecture

    CERN Document Server

    Chu, Yaohan

    1975-01-01

    High-Level Language Computer Architecture offers a tutorial on high-level language computer architecture, including von Neumann architecture and syntax-oriented architecture as well as direct and indirect execution architecture. Design concepts of Japanese-language data processing systems are discussed, along with the architecture of stack machines and the SYMBOL computer system. The conceptual design of a direct high-level language processor is also described.Comprised of seven chapters, this book first presents a classification of high-level language computer architecture according to the pr

  11. Measurement of the 36Cl deposition flux in central Japan: natural background levels and seasonal variability

    International Nuclear Information System (INIS)

    Tosaki, Yuki; Tase, Norio; Sasa, Kimikazu; Takahashi, Tsutomu; Nagashima, Yasuo

    2012-01-01

    Essential parameters for the applications of 36 Cl as a tracer in groundwater studies include the initial 36 Cl/Cl ratio, at the time of recharge, and/or the natural background deposition flux of 36 Cl in the recharge area. To facilitate the hydrological use of 36 Cl in central Japan, this study aimed to obtain a precise estimate of the long-term average local 36 Cl flux and to characterize its seasonal variability. The 36 Cl in precipitation was continuously monitored in Tsukuba, central Japan over a period of >5 years. The 36 Cl flux showed a clear seasonal variation with an annual peak during the spring, which was attributed to the seasonal variability of tropopause height. The long-term average 36 Cl flux (32 ± 2 atoms m −2 s −1 ), estimated from the measured data, was consistent with the prediction from the 36 Cl latitudinal fallout model scaled using the global mean production rate of 20 atoms m −2 s −1 . The initial 36 Cl/Cl ratio was estimated to be (41 ± 6) × 10 −15 , which is similar to that of pre-bomb groundwater in the Tsukuba Upland. An observation period covering an 11-year solar cycle would yield more accurate estimates of the values, given the increased 36 Cl flux during the solar minimum. - Highlights: ► We monitored 36 Cl in precipitation in central Japan over a period of >5 years. ► The 36 Cl flux varied seasonally, with a peak in spring. ► The long-term average 36 Cl flux and the initial 36 Cl/Cl ratio were 32 ± 2 atoms m −2 s −1 and (41 ± 6) × 10 −15 , respectively. ► An observation period covering an 11-year solar cycle would yield more accurate estimates of the values, given the increased 36 Cl flux during the solar minimum.

  12. Automated detection of macular drusen using geometric background leveling and threshold selection.

    Science.gov (United States)

    Smith, R Theodore; Chan, Jackie K; Nagasaki, Takayuki; Ahmad, Umer F; Barbazetto, Irene; Sparrow, Janet; Figueroa, Marta; Merriam, Joanna

    2005-02-01

    Age-related macular degeneration (ARMD) is the most prevalent cause of visual loss in patients older than 60 years in the United States. Observation of drusen is the hallmark finding in the clinical evaluation of ARMD. To segment and quantify drusen found in patients with ARMD using image analysis and to compare the efficacy of image analysis segmentation with that of stereoscopic manual grading of drusen. Retrospective study. University referral center.Patients Photographs were randomly selected from an available database of patients with known ARMD in the ongoing Columbia University Macular Genetics Study. All patients were white and older than 60 years. Twenty images from 17 patients were selected as representative of common manifestations of drusen. Image preprocessing included automated color balancing and, where necessary, manual segmentation of confounding lesions such as geographic atrophy (3 images). The operator then chose among 3 automated processing options suggested by predominant drusen type. Automated processing consisted of elimination of background variability by a mathematical model and subsequent histogram-based threshold selection. A retinal specialist using a graphic tablet while viewing stereo pairs constructed digital drusen drawings for each image. The sensitivity and specificity of drusen segmentation using the automated method with respect to manual stereoscopic drusen drawings were calculated on a rigorous pixel-by-pixel basis. The median sensitivity and specificity of automated segmentation were 70% and 81%, respectively. After preprocessing and option choice, reproducibility of automated drusen segmentation was necessarily 100%. Automated drusen segmentation can be reliably performed on digital fundus photographs and result in successful quantification of drusen in a more precise manner than is traditionally possible with manual stereoscopic grading of drusen. With only minor preprocessing requirements, this automated detection

  13. Contrasting morphology and training background in waterpolo teams of different competitive levels

    Directory of Open Access Journals (Sweden)

    Sofia Canossa

    2014-09-01

    Full Text Available We aimed to describe and compare the general morphological, somatotype and training background characteristics of Iberian waterpolo players (22 Portuguese and 22 Spanish National Teams players considering their playing positions. The International Working Group of Kinanthropometry guidelines was herein followed, and a somatochart was obtained through specific software (Somatotype, Calculation and Analysis. (c2001 SWEAT technologies. Spanish players train more hours per week (22.8 ±9.5 vs.12.2 ±5.6, are taller (187.4 cm ±6.6 vs.180.3 cm ±5.1, heavier (89.2 kg ±11.6 vs.79.1 kg ±10.0, show higher arm span (195.7 cm ±8.5 vs.185.2 cm ±7.4 and muscle mass percentage (49.0% ± 1.8 vs.46.0% ±6.0, and tend to be more mesomorphic (5.19 ±1.27 vs.4.26 ±1.32 than the Portuguese players. Concerning field positions, Spanish center forward players train more hours per week than the Portuguese (20.2 ±9.1 vs.12.2 ±3.8 and show higher arm span (204.4 cm ±7.3 vs.184.0 cm ±6.5. Spanish goal keepers and outside players show higher muscle mass percentage (49.8% ±1.5 vs.42.2% ±5.2 and 49.4% ±1.5 vs.45.5% ±4.6, respectively than the Portuguese players. These evidences should be taken into account for the improvement of waterpolo sport.

  14. Atmospheric tritium concentrations under influence of AREVA NC La Hague reprocessing plant (France) and background levels.

    Science.gov (United States)

    Connan, O; Hébert, D; Solier, L; Maro, D; Pellerin, G; Voiseux, C; Lamotte, M; Laguionie, P

    2017-10-01

    In-air tritium measurements were conducted around the AREVA NC La Hague reprocessing plant, as well as on other sites that are not impacted by the nuclear industry in northwest of France. The results indicate that the dominant tritium form around the AREVA site is HT (86%). HT and HTO levels are lower than 5 and 1 Bq. m -3 for hourly samples taken in the plume. No tritiated organic molecules (TOM) were detected. 26 measurement campaigns were performed and links were established between near-field 85 Kr, HT and HTO activities. Environmental measurements are in line with those taken at the discharge stack, and tend to demonstrate that there are no rapid changes in the tritium forms released. Out of the influence of any nuclear activities, the levels measured were below 13 mBq.m -3 for HT and 5 mBq.m -3 for HTO (<0.5 Bq. L -1 ). HTO level in air seems to be influenced by HTO activities in surrounding seawater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Flat tree-level inflationary potentials in the light of cosmic microwave background and large scale structure data

    CERN Document Server

    Ballesteros, G; Espinosa, J R; de Austri, R Ruiz; Trotta, R

    2008-01-01

    We use cosmic microwave background and large scale structure data to test a broad and physically well-motivated class of inflationary models: those with flat tree-level potentials (typical in supersymmetry). The non-trivial features of the potential arise from radiative corrections which give a simple logarithmic dependence on the inflaton field, making the models very predictive. We also consider a modified scenario with new physics beyond a certain high-energy cut-off showing up as non-renormalizable operators (NRO) in the inflaton field. We find that both kinds of models fit remarkably well CMB and LSS data, with very few free parameters. Besides, a large part of these models naturally predict a reasonable number of e-folds. A robust feature of these scenarios is the smallness of tensor perturbations (r < 10^{-3}). The NRO case can give a sizeable running of the spectral index while achieving a sufficient number of e-folds. We use Bayesian model comparison tools to assess the relative performance of the...

  16. Bridging the gap between actual and required mathematics background at undergraduate university level

    DEFF Research Database (Denmark)

    Triantafyllou, Eva; Timcenko, Olga

    courses of Medialogy, e.g. computer graphics programming. Moreover, this poor performance in mathematics is one of the main causes for dropout at university level. This paper presents our ongoing research aiming at tackling with this problem by developing dynamic and multimodal media for math- ematics...... teaching and learning which will make mathematics more at- tractive and easier to understand to undergraduate students. These tools realise an interactive educational method by giving mathematics learners opportunities to develop visualization skills, explore mathe- matical concepts, and obtain solutions...

  17. Radioactivity in food crops from high background radiation area in southwest area

    International Nuclear Information System (INIS)

    Shanthi, G.; Maniyan, C.G.; Allan Gnana Raj, G.; Thampi Thanka Kumaran, J.

    2009-01-01

    The study was carried out to evaluate radioactive concentration in food crops grown in naturally high-background radiation areas in southwest India. Seventeen varieties of food crops were collected from different parts of Kanyakumari district. The gross alpha and beta activities of the collected samples were measured using alpha scintillation counter and low beta counter respectively. The alpha activity was maximum in tapioca (497± 72 Bq kg -1 ) and the beta activity was maximum in paddy grain (10,946±583 Bq kg -1 ). The gamma activity of the food samples was studied by measuring the activity concentration of the radionuclides ( 226 Ra, 228 Th, 238 U, 40 K) in the food crops. The radioactivity content of the food crops from high-background radiation area was higher when compared to similar samples collected from low-background radiation area. The daily radionuclide intake from the food crops grown and consumed by the public was 127.696 Bq and daily internal dose resulting from ingestion of radionuclides in food was 2.34 μSv. (author)

  18. Tritium and 14C background levels in pristine aquatic systems and their potential sources of variability

    International Nuclear Information System (INIS)

    Eyrolle-Boyer, Frédérique; Claval, David; Cossonnet, Catherine; Zebracki, Mathilde; Gairoard, Stéphanie; Radakovitch, Olivier; Calmon, Philippe; Leclerc, Elisabeth

    2015-01-01

    Tritium and 14 C are currently the two main radionuclides discharged by nuclear industry. Tritium integrates into and closely follows the water cycle and, as shown recently the carbon cycle, as does 14 C (Eyrolle-Boyer et al., 2014a, b). As a result, these two elements persist in both terrestrial and aquatic environments according to the recycling rates of organic matter. Although on average the organically bound tritium (OBT) activity of sediments in pristine rivers does not significantly differ today (2007–2012) from the mean tritiated water (HTO) content on record for rainwater (2.4 ± 0.6 Bq/L and 1.6 ± 0.4 Bq/L, respectively), regional differences are expected depending on the biomass inventories affected by atmospheric global fallout from nuclear testing and the recycling rate of organic matter within watersheds. The results obtained between 2007 and 2012 for 14 C show that the levels varied between 94.5 ± 1.5 and 234 ± 2.7 Bq/kg of C for the sediments in French rivers and across a slightly higher range of 199 ± 1.3 to 238 ± 3.1 Bq/kg of C for fish. This variation is most probably due to preferential uptake of some organic carbon compounds by fish restraining 14 C dilution with refractory organic carbon and/or with old carbonates both depleted in 14 C. Overall, most of these ranges of values are below the mean baseline value for the terrestrial environment (232.0 ± 1.8 Bq/kg of C in 2012, Roussel-Debet, 2014a) in relation to dilution by the carbonates and/or fossil organic carbon present in aquatic systems. This emphasises yet again the value of establishing regional baseline value ranges for these two radionuclides in order to account for palaeoclimatic and lithological variations. Besides, our results obtained from sedimentary archive investigation have confirmed the delayed contamination of aquatic sediments by tritium from the past nuclear tests atmospheric fallout, as recently demonstrated from data chronicles (Eyrolle-Boyer et al., 2014a

  19. Intercomparison of natural and technologically enhanced background radiation levels in Micronesia

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.

    1982-01-01

    The United States Pacific Nuclear Testing Program resulted in local and regional fallout contamination of islands in the central Pacific basin, in an area which is generically known as Micronesia. Since all of the Marshall Islands are low coral islands or atolls, the natural radioactivity content of their soil is among the lowest on earth. In contrast, the high islands of the Caroline groups, to the west of the Marshalls, are characterized by volcanic soils having a significant complement of radionuclides of the uranium and thorium chains. Several field trips between 1975 and 1980 have afforded opportunities to study the natural radiation environments of the coral atolls of the Marshalls and several high islands in the Carolines. The results of these studies have indicated that significant contributions from radioactive fallout can be evaluated in-situ with relative ease on coral islands. In contrast, the higher natural radioactivity content of high island soils, as well as the greater distance of these islands from the test areas, combine to make evaluations of local fallout contributions from US Pacific tests indistinguishable from the contributions of the world-wide fallout

  20. On the contribution of active galactic nuclei to the high-redshift metagalactic ionizing background

    Science.gov (United States)

    D'Aloisio, Anson; Upton Sanderbeck, Phoebe R.; McQuinn, Matthew; Trac, Hy; Shapiro, Paul R.

    2017-07-01

    Motivated by the claimed detection of a large population of faint active galactic nuclei (AGNs) at high redshift, recent studies have proposed models in which AGNs contribute significantly to the z > 4 H I ionizing background. In some models, AGNs are even the chief sources of reionization. If proved true, these models would make necessary a complete revision to the standard view that galaxies dominated the high-redshift ionizing background. It has been suggested that AGN-dominated models can better account for two recent observations that appear to be in conflict with the standard view: (1) large opacity variations in the z ˜ 5.5 H I Ly α forest, and (2) slow evolution in the mean opacity of the He II Ly α forest. Large spatial fluctuations in the ionizing background from the brightness and rarity of AGNs may account for the former, while the earlier onset of He II reionization in these models may account for the latter. Here we show that models in which AGN emissions source ≳50 per cent of the ionizing background generally provide a better fit to the observed H I Ly α forest opacity variations compared to standard galaxy-dominated models. However, we argue that these AGN-dominated models are in tension with constraints on the thermal history of the intergalactic medium (IGM). Under standard assumptions about the spectra of AGNs, we show that the earlier onset of He II reionization heats up the IGM well above recent temperature measurements. We further argue that the slower evolution of the mean opacity of the He II Ly α forest relative to simulations may reflect deficiencies in current simulations rather than favour AGN-dominated models as has been suggested.

  1. Historical background and overview of epidemiological studies on the effects of low-level radiation

    International Nuclear Information System (INIS)

    Upton, A.C.

    1983-01-01

    Recognition of the carcinogenic effects of ionizing radiation dates from the early part of this century, when an increased frequency of skin cancer and leukemia was first reported in radiologists. In the interim, systematic epidemiological studies have disclosed additional carcinogenic effects in radiation workers, A-bomb survivors, patients exposed to diagnostic or therapeutic radiation, and other groups. The studies have provided sufficient data on dose-incidence relationships, the distribution of cancer in relation to age at irradiation and time after exposure, and organ-variations in susceptibility to enable attempts at quantitative assessment of the risks of low-level irradiation. Such assessments, although tentative and controversial, have exerted an important influence on developments in radiological protection

  2. For grasping the Pu background level in the soils of environment around Kyoto University Reactor

    International Nuclear Information System (INIS)

    Ikeda, E.; Fujikawa, Y.; Fukui, M.; Saito, M.

    2001-01-01

    In the case of emergency evaluation of the contamination level of plutonium at the environment in a short time is required. R and D of plutonium analysis in a soil is performed using ICP-MS. The detection limit of the plutonium by ICP-MS is almost same as 2mBq, which is the detection goal of α-ray spectrometry by Japan Analysis Center. It became possible to carry out the quantitative analysis of fall out plutonium at the environment in a short time of about several ten seconds. For the soils used in the analysis experiment the dry and combustion processes were found to be able to skip, which is for removing the organic compounds through the pretreatment of the specimen. (Katsuta, H.)

  3. Other-than-high-level waste

    International Nuclear Information System (INIS)

    Bray, G.R.

    1976-01-01

    The main emphasis of the work in the area of partitioning transuranic elements from waste has been in the area of high-level liquid waste. But there are ''other-than-high-level wastes'' generated by the back end of the nuclear fuel cycle that are both large in volume and contaminated with significant quantities of transuranic elements. The combined volume of these other wastes is approximately 50 times that of the solidified high-level waste. These other wastes also contain up to 75% of the transuranic elements associated with waste generated by the back end of the fuel cycle. Therefore, any detailed evaluation of partitioning as a viable waste management option must address both high-level wastes and ''other-than-high-level wastes.''

  4. ON THE EFFECT OF THE COSMIC MICROWAVE BACKGROUND IN HIGH-REDSHIFT (SUB-)MILLIMETER OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Da Cunha, Elisabete; Groves, Brent; Walter, Fabian; Decarli, Roberto; Rix, Hans-Walter [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Weiss, Axel [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Bertoldi, Frank [Argelander Institute for Astronomy, University of Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany); Carilli, Chris [National Radio Astronomy Observatory, Pete V. Domenici Array Science Center, P.O. Box O, Socorro, NM 87801 (United States); Daddi, Emanuele; Sargent, Mark [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d' Astrophysique, CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Elbaz, David; Ivison, Rob [UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Maiolino, Roberto [Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Riechers, Dominik [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Smail, Ian, E-mail: cunha@mpia.de [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom)

    2013-03-20

    Modern (sub-)millimeter interferometers enable the measurement of the cool gas and dust emission of high-redshift galaxies (z > 5). However, at these redshifts the cosmic microwave background (CMB) temperature is higher, approaching, and even exceeding, the temperature of cold dust and molecular gas observed in the local universe. In this paper, we discuss the impact of the warmer CMB on (sub-)millimeter observations of high-redshift galaxies. The CMB affects the observed (sub-)millimeter dust continuum and the line emission (e.g., carbon monoxide, CO) in two ways: (1) it provides an additional source of (both dust and gas) heating and (2) it is a non-negligible background against which the line and continuum emission are measured. We show that these two competing processes affect the way we interpret the dust and gas properties of high-redshift galaxies using spectral energy distribution models. We quantify these effects and provide correction factors to compute what fraction of the intrinsic dust (and line) emission can be detected against the CMB as a function of frequency, redshift, and temperature. We discuss implications on the derived properties of high-redshift galaxies from (sub-)millimeter data. Specifically, the inferred dust and molecular gas masses can be severely underestimated for cold systems if the impact of the CMB is not properly taken into account.

  5. Comparison of background levels of culturable fungal spore concentrations in indoor and outdoor air in southeastern Austria

    Science.gov (United States)

    Haas, D.; Habib, J.; Luxner, J.; Galler, H.; Zarfel, G.; Schlacher, R.; Friedl, H.; Reinthaler, F. F.

    2014-12-01

    Background concentrations of airborne fungi are indispensable criteria for an assessment of fungal concentrations indoors and in the ambient air. The goal of this study was to define the natural background values of culturable fungal spore concentrations as reference values for the assessment of moldy buildings. The concentrations of culturable fungi were determined outdoors as well as indoors in 185 dwellings without visible mold, obvious moisture problems or musty odor. Samples were collected using the MAS-100® microbiological air sampler. The study shows a characteristic seasonal influence on the background levels of Cladosporium, Penicillium and Aspergillus. Cladosporium sp. had a strong outdoor presence, whereas Aspergillus sp. and Penicillium sp. were typical indoor fungi. For the region of Styria, the median outdoor concentrations are between 100 and 940 cfu/m³ for culturable xerophilic fungi in the course of the year. Indoors, median background levels are between 180 and 420 cfu/m³ for xerophilic fungi. The I/O ratios of the airborne fungal spore concentrations were between 0.2 and 2.0. For the assessment of indoor and outdoor air samples the dominant genera Cladosporium, Penicillium and Aspergillus should receive special consideration.

  6. Remedial action in areas of enhanced natural background radiation levels (with particular emphasis in areas with mineral sand mining residues)

    International Nuclear Information System (INIS)

    Swindon, T.N.

    1985-01-01

    In areas where individuals may receive doses from natural background sources which are higher than those received in areas of normal background radiation, it may be considered desirable that some remedial action be taken to reduce those doses. Contributions to these higher doses may be through high gamma ray fields from the ground or from the use of local building materials, the intake of food or water derived from the areas or of food covered with dust from the areas, the ingestion of dirt and the inhalation of dust, and radon or thoron. Guidelines for remedial action in areas where residues from mineral sand mining and processing have been deposited are given

  7. Tritium and 14C background levels in pristine aquatic systems and their potential sources of variability.

    Science.gov (United States)

    Eyrolle-Boyer, Frédérique; Claval, David; Cossonnet, Catherine; Zebracki, Mathilde; Gairoard, Stéphanie; Radakovitch, Olivier; Calmon, Philippe; Leclerc, Elisabeth

    2015-01-01

    Tritium and (14)C are currently the two main radionuclides discharged by nuclear industry. Tritium integrates into and closely follows the water cycle and, as shown recently the carbon cycle, as does (14)C (Eyrolle-Boyer et al., 2014a, b). As a result, these two elements persist in both terrestrial and aquatic environments according to the recycling rates of organic matter. Although on average the organically bound tritium (OBT) activity of sediments in pristine rivers does not significantly differ today (2007-2012) from the mean tritiated water (HTO) content on record for rainwater (2.4 ± 0.6 Bq/L and 1.6 ± 0.4 Bq/L, respectively), regional differences are expected depending on the biomass inventories affected by atmospheric global fallout from nuclear testing and the recycling rate of organic matter within watersheds. The results obtained between 2007 and 2012 for (14)C show that the levels varied between 94.5 ± 1.5 and 234 ± 2.7 Bq/kg of C for the sediments in French rivers and across a slightly higher range of 199 ± 1.3 to 238 ± 3.1 Bq/kg of C for fish. This variation is most probably due to preferential uptake of some organic carbon compounds by fish restraining (14)C dilution with refractory organic carbon and/or with old carbonates both depleted in (14)C. Overall, most of these ranges of values are below the mean baseline value for the terrestrial environment (232.0 ± 1.8 Bq/kg of C in 2012, Roussel-Debet, 2014a) in relation to dilution by the carbonates and/or fossil organic carbon present in aquatic systems. This emphasises yet again the value of establishing regional baseline value ranges for these two radionuclides in order to account for palaeoclimatic and lithological variations. Besides, our results obtained from sedimentary archive investigation have confirmed the delayed contamination of aquatic sediments by tritium from the past nuclear tests atmospheric fallout, as recently demonstrated from data chronicles (Eyrolle

  8. Study of the CMS RPC detector performance in high radiation background conditions

    CERN Document Server

    Miguel Colin, Osvaldo

    2017-01-01

    The RPC system at the CMS Detector is operating successfully from beginning of the data taking. The high instantaneous luminosity causes an extremely high flux of ionizing particles. The long period of operation (Run1 and Run2) in a huge radiation background conditions, gives the opportunity to study the operation capability of the RPCs and also to predict a data-driven extrapolation about the expecting particle rates at HL LHC (High Luminosity) scenario. The obtained results in terms of measured rate, currents and integrated charged will be presented in the poster. When it is possible they will be compared to the relevant results obtained from the dedicated study where a set of test chambers have been irradiated at GIF++ laboratory setup.

  9. State Recognition of High Voltage Isolation Switch Based on Background Difference and Iterative Search

    Science.gov (United States)

    Xu, Jiayuan; Yu, Chengtao; Bo, Bin; Xue, Yu; Xu, Changfu; Chaminda, P. R. Dushantha; Hu, Chengbo; Peng, Kai

    2018-03-01

    The automatic recognition of the high voltage isolation switch by remote video monitoring is an effective means to ensure the safety of the personnel and the equipment. The existing methods mainly include two ways: improving monitoring accuracy and adopting target detection technology through equipment transformation. Such a method is often applied to specific scenarios, with limited application scope and high cost. To solve this problem, a high voltage isolation switch state recognition method based on background difference and iterative search is proposed in this paper. The initial position of the switch is detected in real time through the background difference method. When the switch starts to open and close, the target tracking algorithm is used to track the motion trajectory of the switch. The opening and closing state of the switch is determined according to the angle variation of the switch tracking point and the center line. The effectiveness of the method is verified by experiments on different switched video frames of switching states. Compared with the traditional methods, this method is more robust and effective.

  10. Dry deposition of sulphur at a high-altitude background station in South Africa

    CSIR Research Space (South Africa)

    Zunckel, M

    1999-10-01

    Full Text Available station also plays a role in the observed day-to-day variation as pollutants are trapped immediately below this layer. The pressure difference between the base of the absolutely stable layer and the surface pressure at Ben MacDhui is used to indicate... AT A HIGH-ALTITUDE BACKGROUND STATION IN SOUTH AFRICA MARK ZUNCKEL1;2 , STUART PIKETH1 and TALI FREIMAN1 1 Climatology Research Group, University of Witwatersrand, Johannesburg, South Africa; 2 CSIR Environmentek, P.O. Box 17001, Congella, South Africa...

  11. Handling and storage of conditioned high-level wastes

    International Nuclear Information System (INIS)

    1983-01-01

    This report deals with certain aspects of the management of one of the most important wastes, i.e. the handling and storage of conditioned (immobilized and packaged) high-level waste from the reprocessing of spent nuclear fuel and, although much of the material presented here is based on information concerning high-level waste from reprocessing LWR fuel, the principles, as well as many of the details involved, are applicable to all fuel types. The report provides illustrative background material on the arising and characteristics of high-level wastes and, qualitatively, their requirements for conditioning. The report introduces the principles important in conditioned high-level waste storage and describes the types of equipment and facilities, used or studied, for handling and storage of such waste. Finally, it discusses the safety and economic aspects that are considered in the design and operation of handling and storage facilities

  12. Handling and storage of conditioned high-level wastes

    International Nuclear Information System (INIS)

    Heafield, W.

    1984-01-01

    This paper deals with certain aspects of the management of one of the most important radioactive wastes arising from the nuclear fuel cycle, i.e. the handling and storage of conditioned high-level wastes. The paper is based on an IAEA report of the same title published during 1983 in the Technical Reports Series. The paper provides illustrative background material on the characteristics of high-level wastes and, qualitatively, their requirements for conditioning. The principles important in the storage of high-level wastes are reviewed in conjunction with the radiological and socio-political considerations involved. Four fundamentally different storage concepts are described with reference to published information and the safety aspects of particular storage concepts are discussed. Finally, overall conclusions are presented which confirm the availability of technology for constructing and operating conditioned high-level waste storage facilities for periods of at least several decades. (author)

  13. Analytical expression for the phantom generated bremsstrahlung background in high energy electron beams

    International Nuclear Information System (INIS)

    Sorcini, B.B.; Hyoedynmaa, S; Brahme, A.

    1995-01-01

    Qualification of the bremsstrahlung photon background generated by an electron beam in a phantom is important for accurate high energy electron beam dosimetry in radiation therapy. An analytical expression has been derived for the background of phantom generated bremsstrahlung photons in plane parallel electron beams normally incident on phantoms of any atomic number between 4 and 92 (Be, C, H 2 O, Al, Cu, Ag, Pb and U). The expression can be used with fairly good accuracy in the energy range between 1 and 50 MeV. The expression is globally based on known scattering power and radiation and collision stopping power data for the phantom material at the mean energy of the incident electrons. The depth dose distribution due to the bremsstrahlung generated in the phantom is derived by folding the bremsstrahlung energy fluence with a simple analytical one-dimensional photon energy deposition kernel. The energy loss of the primary electrons and the generation, attenuation and absorption of bremsstrahlung photons are taken into account in the analytical formula. The photon energy deposition kernel is used to account for the bremsstrahlung produced at one depth that will contribute to the down stream dose. A simple analytical expression for photon energy deposition kernel is consistent with the classical analytical relation describing the photon depth dose distribution. From the surface to the practical range the photon dose increases almost linearly due to accumulation and buildup of the photon produced at different phantom layers. At depths beyond the practical range a simple exponential function can be use to describe the bremsstrahlung attenuation in the phantom. For comparison Monte Carlo calculated distributions using ITS3 Monte Carlo Code were used. Good agreement is found between the analytical expression and Monte Carlo calculation. Deviations of 5% from Monte Carlo calculated bremmstrahlung background are observed for high atomic number materials. The method can

  14. High repetition rate laser-driven MeV ion acceleration at variable background pressures

    Science.gov (United States)

    Snyder, Joseph; Ngirmang, Gregory; Orban, Chris; Feister, Scott; Morrison, John; Frische, Kyle; Chowdhury, Enam; Roquemore, W. M.

    2017-10-01

    Ultra-intense laser-plasma interactions (LPI) can produce highly energetic photons, electrons, and ions with numerous potential real-world applications. Many of these applications will require repeatable, high repetition targets that are suitable for LPI experiments. Liquid targets can meet many of these needs, but they typically require higher chamber pressure than is used for many low repetition rate experiments. The effect of background pressure on the LPI has not been thoroughly studied. With this in mind, the Extreme Light group at the Air Force Research Lab has carried out MeV ion and electron acceleration experiments at kHz repetition rate with background pressures ranging from 30 mTorr to >1 Torr using a submicron ethylene glycol liquid sheet target. We present these results and provide two-dimensional particle-in-cell simulation results that offer insight on the thresholds for the efficient acceleration of electrons and ions. This research is supported by the Air Force Office of Scientific Research under LRIR Project 17RQCOR504 under the management of Dr. Riq Parra and Dr. Jean-Luc Cambier. Support was also provided by the DOD HPCMP Internship Program.

  15. A survey of senile dementia in the high background radiation areas in Yangjiang, China

    International Nuclear Information System (INIS)

    Li Jia; Su Gasaki, H.; Yang Yuhua

    1997-01-01

    Objective: To evaluate the effects of long-term low dose and low dose-rate ionizing radiation exposure on the prevalence rate of senile dementia, further assess the effects of low-dose radiation exposure on central nervous system and study the pathogen of senile dementia, and provide direct observational data of human beings. Methods: A cross-sectional study of the prevalence of senile dementia was carried out in high background radiation areas in Yangjiang, Guangdong Province, China. The survey was conducted in two stages. For the initial screening, Hasegawa Dementia Scale (HDS) was used for all subjects. In the second stage, the stage of diagnosis, special questionnaires of healthy state of old people were sued. The final diagnoses were made according to the third revised edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM III-R) of American Psychiatric Association. Results: 1018 inhabitants aged 65 years and over, including 513 persons in HBRA and 505 in CA were observed. According to DSM III-R, 61 cases (31 cases in HBRA and 30 cases in CA) of senile dementia were diagnosed. The prevalence rates of senile dementia are 6.04% in HBRA and 5.94% in CA, the total prevalence rate being 5.99%. Conclusion: No significant statistical difference in the prevalence rate of senile dementia between the two areas was found, suggesting that the prevalence rate of senile dementia in these areas is not associated with the high background radiation exposure

  16. SIGWX Charts - High Level Significant Weather

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — High level significant weather (SIGWX) forecasts are provided for the en-route portion of international flights. NOAA's National Weather Service Aviation Center...

  17. PM10 concentration levels at an urban and background site in Cyprus: the impact of urban sources and dust storms.

    Science.gov (United States)

    Achilleos, Souzana; Evans, John S; Yiallouros, Panayiotis K; Kleanthous, Savvas; Schwartz, Joel; Koutrakis, Petros

    2014-12-01

    Air quality in Cyprus is influenced by both local and transported pollution, including desert dust storms. We examined PM10 concentration data collected in Nicosia (urban representative) from April 1, 1993, through December 11, 2008, and in Ayia Marina (rural background representative) from January 1, 1999, through December 31, 2008. Measurements were conducted using a Tapered Element Oscillating Micro-balance (TEOM). PM10 concentrations, meteorological records, and satellite data were used to identify dust storm days. We investigated long-term trends using a Generalized Additive Model (GAM) after controlling for day of week, month, temperature, wind speed, and relative humidity. In Nicosia, annual PM10 concentrations ranged from 50.4 to 63.8 μg/m3 and exceeded the EU annual standard limit enacted in 2005 of 40 μg/m3 every year A large, statistically significant impact of urban sources (defined as the difference between urban and background levels) was seen in Nicosia over the period 2000-2008, and was highest during traffic hours, weekdays, cold months, and low wind conditions. Our estimate of the mean (standard error) contribution of urban sources to the daily ambient PM10 was 24.0 (0.4) μg/m3. The study of yearly trends showed that PM10 levels in Nicosia decreased from 59.4 μg/m3 in 1993 to 49.0 μg/m3 in 2008, probably in part as a result of traffic emission control policies in Cyprus. In Ayia Marina, annual concentrations ranged from 27.3 to 35.6 μg/m3, and no obvious time trends were observed. The levels measured at the Cyprus background site are comparable to background concentrations reported in other Eastern Mediterranean countries. Average daily PM10 concentrations during desert dust storms were around 100 μg/m3 since 2000 and much higher in earlier years. Despite the large impact ofdust storms and their increasing frequency over time, dust storms were responsible for a small fraction of the exceedances of the daily PM10 limit. Implications: This

  18. Recovering method for high level radioactive material

    International Nuclear Information System (INIS)

    Fukui, Toshiki

    1998-01-01

    Offgas filters such as of nuclear fuel reprocessing facilities and waste control facilities are burnt, and the burnt ash is melted by heating, and then the molten ashes are brought into contact with a molten metal having a low boiling point to transfer the high level radioactive materials in the molten ash to the molten metal. Then, only the molten metal is evaporated and solidified by drying, and residual high level radioactive materials are recovered. According to this method, the high level radioactive materials in the molten ashes are transferred to the molten metal and separated by the difference of the distribution rate of the molten ash and the molten metal. Subsequently, the molten metal to which the high level radioactive materials are transferred is heated to a temperature higher than the boiling point so that only the molten metal is evaporated and dried to be removed, and residual high level radioactive materials are recovered easily. On the other hand, the molten ash from which the high level radioactive material is removed can be discarded as ordinary industrial wastes as they are. (T.M.)

  19. High dynamic range low-noise focal plane readout for VLWIR applications implemented with current mode background subtraction

    Science.gov (United States)

    Yang, Guang; Sun, Chao; Shaw, Timothy; Wrigley, Chris; Peddada, Pavani; Blazejewski, Edward R.; Pain, Bedabrata

    1998-09-01

    Design and operation of a low noise CMOS focal pa;ne readout circuit with ultra-high charge handling capacity is presented. Designed for high-background, VLWIR detector readout, each readout unit cell use an accurate dynamic current memory for automatic subtraction of the dark pedestal in current domain enabling measurement of small signals 85 dB below the dark level. The redout circuit operates with low-power dissipation, high linearity, and is capable of handling pedestal currents up to 300 nA. Measurements indicate an effective charge handling capacity of over 5 X 10(superscript 9) charges/pixel with less than 10(superscript 5) electrons of input referred noise.

  20. Disposal of high level and intermediate level radioactive wastes

    International Nuclear Information System (INIS)

    Flowers, R.H.

    1991-01-01

    The waste products from the nuclear industry are relatively small in volume. Apart from a few minor gaseous and liquid waste streams, containing readily dispersible elements of low radiotoxicity, all these products are processed into stable solid packages for disposal in underground repositories. Because the volumes are small, and because radioactive wastes are latecomers on the industrial scene, a whole new industry with a world-wide technological infrastructure has grown up alongside the nuclear power industry to carry out the waste processing and disposal to very high standards. Some of the technical approaches used, and the Regulatory controls which have been developed, will undoubtedly find application in the future to the management of non-radioactive toxic wastes. The repository site outlined would contain even high-level radioactive wastes and spent fuels being contained without significant radiation dose rates to the public. Water pathway dose rates are likely to be lowest for vitrified high-level wastes with spent PWR fuel and intermediate level wastes being somewhat higher. (author)

  1. Current high-level waste solidification technology

    International Nuclear Information System (INIS)

    Bonner, W.F.; Ross, W.A.

    1976-01-01

    Technology has been developed in the U.S. and abroad for solidification of high-level waste from nuclear power production. Several processes have been demonstrated with actual radioactive waste and are now being prepared for use in the commercial nuclear industry. Conversion of the waste to a glass form is favored because of its high degree of nondispersibility and safety

  2. Estimation of /sup 65/Zn background levels for marine coastal waters. [Data from northeast Pacific coast for August 1964

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, G V; Rowland, R H

    1966-04-09

    Data are presented on Zn and /sup 65/Zn contents in tissues of marine animals collected along the Pacific coast near to and remote from the Columbia River. Specimens of barnacles, starfish, and mussels were collected during August of 1964. Tissues were dried by lyophilization and the radioisotope concentration was determined with a whole-body counter. To evaluate the background contamination level of /sup 65/Zn on the Pacific coast, /sup 54/Mn analyses were included to differentiate the contribution of fallout and /sup 51/Cr was determined to evaluate the contribution from the Columbia River. It was concluded that coastal /sup 65/Zn levels result essentially from fallout and that the present level in fallout is relatively constant at 0.05 to 2.7 pc /sup 65/Zn/mg Zn.

  3. High-Level Application Framework for LCLS

    Energy Technology Data Exchange (ETDEWEB)

    Chu, P; Chevtsov, S.; Fairley, D.; Larrieu, C.; Rock, J.; Rogind, D.; White, G.; Zalazny, M.; /SLAC

    2008-04-22

    A framework for high level accelerator application software is being developed for the Linac Coherent Light Source (LCLS). The framework is based on plug-in technology developed by an open source project, Eclipse. Many existing functionalities provided by Eclipse are available to high-level applications written within this framework. The framework also contains static data storage configuration and dynamic data connectivity. Because the framework is Eclipse-based, it is highly compatible with any other Eclipse plug-ins. The entire infrastructure of the software framework will be presented. Planned applications and plug-ins based on the framework are also presented.

  4. A novel robust and efficient algorithm for charge particle tracking in high background flux

    International Nuclear Information System (INIS)

    Fanelli, C; Cisbani, E; Dotto, A Del

    2015-01-01

    The high luminosity that will be reached in the new generation of High Energy Particle and Nuclear physics experiments implies large high background rate and large tracker occupancy, representing therefore a new challenge for particle tracking algorithms. For instance, at Jefferson Laboratory (JLab) (VA,USA), one of the most demanding experiment in this respect, performed with a 12 GeV electron beam, is characterized by a luminosity up to 10 39 cm -2 s -1 . To this scope, Gaseous Electron Multiplier (GEM) based trackers are under development for a new spectrometer that will operate at these high rates in the Hall A of JLab. Within this context, we developed a new tracking algorithm, based on a multistep approach: (i) all hardware - time and charge - information are exploited to minimize the number of hits to associate; (ii) a dedicated Neural Network (NN) has been designed for a fast and efficient association of the hits measured by the GEM detector; (iii) the measurements of the associated hits are further improved in resolution through the application of Kalman filter and Rauch- Tung-Striebel smoother. The algorithm is shortly presented along with a discussion of the promising first results. (paper)

  5. Adolescent gynecomastia is associated with a high incidence of obesity, dysglycemia, and family background of diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Bindu Kulshreshtha

    2017-01-01

    Full Text Available Background: Gynecomastia during adolescence is common though etiology is not clear. We studied the clinical and hormonal profile of adolescent patients with gynecomastia. Methodology: Patients who had onset of breast development between age 10 and 20 years were included in this study. Their clinical profile, biochemical, and hormonal parameters were studied. Results: Of 94 patients with gynecomastia, 4 had hypogonadotropic hypogonadism, 4 had hypergonadotropic hypogonadism, and 1 had fibroadenosis, but in majority (90.4%, no apparent cause for breast enlargement was evident. In the idiopathic group, majority were obese (63%. Fourteen (16% patients had impaired fasting glucose or impaired glucose tolerance. Another twenty patients had subtle abnormalities (high 1 h glucose or glucose peak at 2 h. Twenty-nine percent of lean and 38% of obese patients had mild abnormalities in glucose profile. Sixty percent of patients had family background of diabetes. Obese patients had lower testosterone as compared to lean patients; however, estradiol, luteinizing hormone, and follicle-stimulating hormone levels were similar in the two groups. Conclusion: Gynecomastia during adolescence is associated with obesity, dysglycemia, and family background of diabetes mellitus.

  6. Concentration of 210Po in local foodstuffs grown nearby High Background Areas (HBRA)

    International Nuclear Information System (INIS)

    Kamesh Viswanathan, B.; Arunachalam, Kantha D.; Sathesh Kumar, A.; Jayakrishna, K.; Rao, D.D.

    2012-01-01

    210 Po is the decay product of natural radionuclide of 238 U series. The presence of a radionuclide migrates from soil > plant > food and ingested by the humans residing in the areas of syentite rocks nearby the High Background Radiation Area's (HBRA). The food samples were studied by Market Basket Study (MBS). The average concentration of 210 Po in foodstuffs like green leafy vegetables, other vegetables, roots and tubers; fruits, fish, other flesh foods, milk and cereals were 1671 ± 163.3, 28.2 ± 7.3, 320 ± 99, 53 ± 17.5, 251.5 ± 54.5, 37 ± 14.5, 16 ± 6 and 230 ± 75 mBq. Kg -1 fresh weight. (author)

  7. Radiation exposure map based on fuzzy logic for the representation of areas with high natural background

    International Nuclear Information System (INIS)

    Vasconcelos, Wagner Eustaquio de; Lira, Carlos Alberto Brayner de Oliveira

    2009-01-01

    The identification of areas with high concentrations of natural radionuclides is an important task in classifying these areas in relation to the health risk for residents in the region. The aim of this work is to identify areas of high exposure to nuclear radiation using a geographic representation based on the theory of fuzzy sets. Radiometric data obtained from previous works developed in a region of high concentrations in natural uranium were used to create a fuzzy map of the local radiation levels. During the image processing, a nonlinear filter was applied to eliminate noise i.e. to reduce isolated pixels that would eventually cause major uncertainties in the results. A resulting image was geographically positioned (WGS40) and obtained in gray scale. This image was fuzzified for membership functions that represent linguistic variables as low exposure, medium exposure and high exposure. After representing the membership grade in a RGB (red, green and blue) image it was possible to visualize the radiation level in the area of exposure. When compared to data from the region, results demonstrated the good efficiency of the technique here employed for the representation of areas with high radioactivity levels. The image obtained also provided important information about those areas where exposure to radiation is more pronounced. Hence, the fuzzy map can be applied in decision-making of experts when a risk situation is identified. (author)

  8. Biological effects of low-dose radiation on human population living in high-background radiation areas of Kerala coast

    International Nuclear Information System (INIS)

    Das, Birajalaxmi

    2016-01-01

    High-level natural radiation areas (HLNRA) of Kerala coast is densely populated and known for its wide variation in background radiation dose levels due to uneven distribution of monazite in the beach sand. The background radiation dose varies from 1 to 45 mGv/y. The areas with >1.5mGy/y is considered as HLNRA. Human population inhabiting in this area are exposed to low-dose chronic radiation since generations. Hence, this population provides an ideal situation to study dose response and adaptive response, if any, due to natural chronic low-dose exposure. It has been investigated extensively to study the biological and health effects of long-term low-dose/low-dose radiation exposure. So far over 150, 000 newborns monitored from hospital-based study did not reveal any significant difference in the incidence of any of the malformations and stillbirth between HLNRA and adjacent control areas. A case-control study on cleft lip/palate and mental retardation did not show any association with background radiation dose. Cytogenetic investigation of over 27,000 newborns did not show any significant increase in the frequency of chromosome aberrations and karyotype anomalies. DNA damage endpoints, such as micronuclei, telomere length and DNA strand breaks, did not reveal any significant difference between control and exposed population. Studies on DNA damage and repair revealed efficient repair of DNA strand breaks in HLNRA individuals. Molecular studies using high throughput microarray analysis indicated a large number of genes involved in various molecular and cellular pathways. Indications of in vivo radioadaptive response due to natural chronic low-dose exposure in this population have important implications to human health. (author)

  9. STS-33 crewmembers on KSC LC Pad 39B 195 ft level with OV-103 in background

    Science.gov (United States)

    1990-01-01

    STS-33 crewmembers, wearing launch and entry suit (LES), take a break from training activities to pose for group portrait in front of Discovery, Orbiter Vehicle (OV) 103, at the 195 ft level elevator entrance at Kennedy Space Center (KSC) Launch Complex (LC) Pad 39B. Left to right are Pilot John E. Blaha, Mission Specialist (MS) Kathryn C. Thornton, MS Manley L. Carter, Jr, Commander Frederick D. Gregory, and MS F. Story Musgrave. Visible in the background is the catwalk to OV-103's side hatch.

  10. Relationship between Background Parenchymal Enhancement on High-risk Screening MRI and Future Breast Cancer Risk.

    Science.gov (United States)

    Grimm, Lars J; Saha, Ashirbani; Ghate, Sujata V; Kim, Connie; Soo, Mary Scott; Yoon, Sora C; Mazurowski, Maciej A

    2018-03-27

    To determine if background parenchymal enhancement (BPE) on screening breast magnetic resonance imaging (MRI) in high-risk women correlates with future cancer. All screening breast MRIs (n = 1039) in high-risk women at our institution from August 1, 2004, to July 30, 2013, were identified. Sixty-one patients who subsequently developed breast cancer were matched 1:2 by age and high-risk indication with patients who did not develop breast cancer (n = 122). Five fellowship-trained breast radiologists independently recorded the BPE. The median reader BPE for each case was calculated and compared between the cancer and control cohorts. Cancer cohort patients were high-risk because of a history of radiation therapy (10%, 6 of 61), high-risk lesion (18%, 11 of 61), or breast cancer (30%, 18 of 61); BRCA mutation (18%, 11 of 61); or family history (25%, 15 of 61). Subsequent malignancies were invasive ductal carcinoma (64%, 39 of 61), ductal carcinoma in situ (30%, 18 of 61) and invasive lobular carcinoma (7%, 4of 61). BPE was significantly higher in the cancer cohort than in the control cohort (P = 0.01). Women with mild, moderate, or marked BPE were 2.5 times more likely to develop breast cancer than women with minimal BPE (odds ratio = 2.5, 95% confidence interval: 1.3-4.8, P = .005). There was fair interreader agreement (κ = 0.39). High-risk women with greater than minimal BPE at screening MRI have increased risk of future breast cancer. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Temporal variability of the bioaerosol background at a subway station: concentration level, size distribution, and diversity of airborne bacteria.

    Science.gov (United States)

    Dybwad, Marius; Skogan, Gunnar; Blatny, Janet Martha

    2014-01-01

    Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10(3) CFU m(-3) and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

  12. Temporal Variability of the Bioaerosol Background at a Subway Station: Concentration Level, Size Distribution, and Diversity of Airborne Bacteria

    Science.gov (United States)

    Dybwad, Marius; Skogan, Gunnar

    2014-01-01

    Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 103 CFU m−3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents. PMID:24162566

  13. EAP high-level product architecture

    DEFF Research Database (Denmark)

    Guðlaugsson, Tómas Vignir; Mortensen, Niels Henrik; Sarban, Rahimullah

    2013-01-01

    EAP technology has the potential to be used in a wide range of applications. This poses the challenge to the EAP component manufacturers to develop components for a wide variety of products. Danfoss Polypower A/S is developing an EAP technology platform, which can form the basis for a variety...... of EAP technology products while keeping complexity under control. High level product architecture has been developed for the mechanical part of EAP transducers, as the foundation for platform development. A generic description of an EAP transducer forms the core of the high level product architecture...... the function of the EAP transducers to be changed, by basing the EAP transducers on a different combination of organ alternatives. A model providing an overview of the high level product architecture has been developed to support daily development and cooperation across development teams. The platform approach...

  14. Towards a High Temporal Frequency Grass Canopy Thermal IR Model for Background Signatures

    Science.gov (United States)

    Ballard, Jerrell R., Jr.; Smith, James A.; Koenig, George G.

    2004-01-01

    In this paper, we present our first results towards understanding high temporal frequency thermal infrared response from a dense plant canopy and compare the application of our model, driven both by slowly varying, time-averaged meteorological conditions and by high frequency measurements of local and within canopy profiles of relative humidity and wind speed, to high frequency thermal infrared observations. Previously, we have employed three-dimensional ray tracing to compute the intercepted and scattered radiation fluxes and for final scene rendering. For the turbulent fluxes, we employed simple resistance models for latent and sensible heat with one-dimensional profiles of relative humidity and wind speed. Our modeling approach has proven successful in capturing the directional and diurnal variation in background thermal infrared signatures. We hypothesize that at these scales, where the model is typically driven by time-averaged, local meteorological conditions, the primary source of thermal variance arises from the spatial distribution of sunlit and shaded foliage elements within the canopy and the associated radiative interactions. In recent experiments, we have begun to focus on the high temporal frequency response of plant canopies in the thermal infrared at 1 second to 5 minute intervals. At these scales, we hypothesize turbulent mixing plays a more dominant role. Our results indicate that in the high frequency domain, the vertical profile of temperature change is tightly coupled to the within canopy wind speed In the results reported here, the canopy cools from the top down with increased wind velocities and heats from the bottom up at low wind velocities. .

  15. Background Atmospheric Levels of Aldehydes, BTEX and PM10 Pollutants in a Medium-Sized City of Southern Italy

    International Nuclear Information System (INIS)

    Iovino, P.; Salvestrini, S.; Capasso, S.

    2007-01-01

    Background atmospheric levels of aldehydes, BTEX and PM10 pollutants were measured in the suburb of Caserta (Italy), 75 thousands inhabitants, 41 0 04' N, on rainless weekdays and weekends during 2005. On weekdays the average daily concentrations (μg m -3 ) were 41.6 PM10, 8.6 benzene, 25.2 toluene, 6.3 ethylbenzene, 14.0 (m+p)-xylene, 11.7 o-xylene, 6.5 formaldehyde, 3.3 acetaldehyde. All the pollutant concentrations were strictly correlated (mean correlation coefficients = 0.90). At weekends the concentrations were lower by about 1.6 times. Both on weekdays and at weekends the PM10 and benzene levels exceeded the limits set by the EU Directive 30/1999 and 69/2000, respectively

  16. Final report and evaluation of the SAWORA research program on background radiation levels from natural origin in The Netherlands

    International Nuclear Information System (INIS)

    Hogeweg, B.

    1986-09-01

    In order to study the various factors which determine the dose resulting from background radiation, in particular for the indoor situation, the SAMORA-programme was initiated in 1982. The various aspects studied were: 1) a determination of the current background radiation level, for the indoor as well as the outdoor situation; 2) an inventory of the radioactivity of the building materials; 3) the radioecological aspects from fly-ash and gypsum deposits; 4) a risk estimation of lung tumour induction at low doses and for low dose rates; 5) technical factors determining the effective dose equivalent. In this report the connection of the results derived in the different studies will be discussed. From the study on radioconcentration it became clear that the indoor concentration is strongly determined by the concentration in the crawl space. On the basis of the results of the programme an estimation of the lung tumour risk for the Dutch population is presented. For the current levels it is calculated that the risk is approximately 2.1 lung tumours per 100.000 persons. Since in 1982 the mean lung tumour death rate for the Dutch population was 56.8 per 100.000, this result demonstrates that the calculated contribution is relatively low (4%). Furthermore it is calculated that the maximum increase of this contribution as a result of the introduction of active gypsum building materials will be of the order of 1%. (Auth.)

  17. World high background natural radiation areas: Need to protect public from radiation exposure

    International Nuclear Information System (INIS)

    Sohrabi, Mehdi

    2013-01-01

    Highlights of findings on radiological measurements, radiobiological and epidemiological studies in some main world high background natural radiation (HBNR) areas such as in Brazil, China, India and Iran are presented and discussed with special regard to remediation of radiation exposure of inhabitants in such areas. The current radiation protection philosophy and recommendations applied to workers and public from operation of radiation and nuclear applications are based on the linear non-threshold (LNT) model. The inhabitants of HBNR and radon prone areas receive relatively high radiation doses. Therefore, according to the LNT concept, the inhabitants in HBNR areas and in particular those in Ramsar are considered at risk and their exposure should be regulated. The HBNR areas in the world have different conditions in terms of dose and population. In particular, the inhabitants in HBNR areas of Ramsar receive very high internal and external exposures. This author believes that the public in such areas should be protected and proposes a plan to remedy high exposure of the inhabitants of the HBNR areas of Ramsar, while maintaining these areas as they stand to establish a national environmental radioactivity park which can be provisionally called “Ramsar Research Natural Radioactivity Park” (RRNRP). The major HBNR areas, the public exposure and the need to remedy exposures of inhabitants are reviewed and discussed. - Highlights: ► Highlights of findings on studies in HBNR areas are reviewed and discussed. ► The need to protect HBNR area inhabitants and remedy public exposure is emphasized. ► A collective approach is proposed to remedy exposure of Ramsar HBNR area inhabitants. ► Relocation of HBNR area inhabitants and establishing a park at the location is proposed. ► The advantages and disadvantages of the methods are discussed and recommendations are made

  18. The management of high-level radioactive wastes

    International Nuclear Information System (INIS)

    Lennemann, Wm.L.

    1979-01-01

    The definition of high-level radioactive wastes is given. The following aspects of high-level radioactive wastes' management are discussed: fuel reprocessing and high-level waste; storage of high-level liquid waste; solidification of high-level waste; interim storage of solidified high-level waste; disposal of high-level waste; disposal of irradiated fuel elements as a waste

  19. Nested case-control study on the risk of nasopharyngeal carcinoma in the high background radiation areas of Yangjiang, China

    International Nuclear Information System (INIS)

    Zou Jianming; Sun Quanfu; Yuan Yongling

    2003-01-01

    Objective: To identify the major determinants of nasopharyngeal carcinoma (NPC) in the high-background radiation areas (HBRA) in Yangjiang, China. Methods: A nested case-control study was conducted based on 106517 subjects. 98 cases that died of NPC were detected during a follow-up program for 9 years. Univariate analysis and multivariate non-conditional logistic regression were used to analyze associations between the exposure factors and NPC. Results: Multivariate conditional logistic regression analysis revealed that education levels, salted fish intake, the history of chronic rhinitis and the family history of NPC were independent risk factors of NPC. Tobacco smoking and alcohol consumption were not significantly related to NPC risk. The ORs of NPC risk comparing HBRA and a nearby control area before and after adjustment for the major risk determinants identified in the present study was 0.86 and 0.87, respectively. Conclusion: Salted fish intake was a strong risk factor of NPC. Education, the history of chronic rhinitis and the family history of NPC were also related to NPC risk. The exposure to high background radiation in HBRA of Yangjiang was not related to NPC risk with or without the adjustment for those major risk determinants of NPC

  20. High-level radioactive wastes. Supplement 1

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1984-09-01

    This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations

  1. PAIRWISE BLENDING OF HIGH LEVEL WASTE

    International Nuclear Information System (INIS)

    CERTA, P.J.

    2006-01-01

    The primary objective of this study is to demonstrate a mission scenario that uses pairwise and incidental blending of high level waste (HLW) to reduce the total mass of HLW glass. Secondary objectives include understanding how recent refinements to the tank waste inventory and solubility assumptions affect the mass of HLW glass and how logistical constraints may affect the efficacy of HLW blending

  2. Materials for high-level waste containment

    International Nuclear Information System (INIS)

    Marsh, G.P.

    1982-01-01

    The function of the high-level radioactive waste container in storage and of a container/overpack combination in disposal is considered. The consequent properties required from potential fabrication materials are discussed. The strategy adopted in selecting containment materials and the experimental programme underway to evaluate them are described. (U.K.)

  3. A case-control study of nasopharyngeal carcinoma in the high background radiation areas of Yangjiang, China

    Energy Technology Data Exchange (ETDEWEB)

    Zou Jianming; Zha Yongru [Guangdong Inst. of Prevention and Treatment of Occupational Diseases, Guangzhou (China); Sun Quanfu; Akiba, Suminori; Yuan Yongling; Tao Zufan; Wei Luxin; Sugahara, Tsutomu

    2000-10-01

    The main purposes of this study were to identify the major determinants of nasopharyngeal carcinoma (NPC) in the high-background radiation areas (HBRA) in Yangjiang, China and to evaluate their potential confounding effects on the NPC risk associated with exposure to high background radiation. A matched case-control study was conducted using those who died of NPC during the period 1987-1995. Two controls were randomly selected for each case from those who died from causes other than malignancies and external causes. Cases and their controls were matched with respect to sex and the years of birth and death ({+-}5 years). Study subjects' next-of-kin were interviewed using a standardized questionnaire to collect information on socioeconomic status, dietary habits, tobacco smoking and alcohol consumption, disease history, pesticide use, medical X-ray exposure, the family history of NPC and so on. We succeeded in interviewing 97 cases and 192 controls. Univariate conditional logistic regression analysis showed that NPC risk was associated with the consumption of salted fish, homemade pickles, and fermented soy beans, education levels, the history of chronic rhinitis, and the family history of NPC. Multivariate conditional logistic regression analysis revealed that education levels (Odds ratio (OR) for middle school or higher levels vs. no school education=3.8, 95% CI=1.2 to 11.8), salted fish intake (OR=3.2, 95% CI=1.7 to 6.1), the history of chronic rhinitis (OR=3.6, 95% CI=1.3 to 10.1), and the family history of NPC (OR=14.2, 95% CI=2.7 to 73.4) were independent risk factors of NPC. Tobacco smoking (OR=1.2, 95% CI=0.7 to 2.1), and alcohol consumption (OR=0.9, 95% CI=0.5 to 1.9) were not significantly related to NPC risk. The ORs of NPC risk comparing HBRA and a nearby control area before and after adjustment for the major risk determinants identified in the present study were 0.86 (95% CI=0.50 to 1.50) and 0.87 (95% CI=0.45 to 1.67), respectively. Salted fish

  4. A case-control study of nasopharyngeal carcinoma in the high background radiation areas of Yangjiang, China

    International Nuclear Information System (INIS)

    Zou Jianming; Zha Yongru; Sun Quanfu; Akiba, Suminori; Yuan Yongling; Tao Zufan; Wei Luxin; Sugahara, Tsutomu

    2000-01-01

    The main purposes of this study were to identify the major determinants of nasopharyngeal carcinoma (NPC) in the high-background radiation areas (HBRA) in Yangjiang, China and to evaluate their potential confounding effects on the NPC risk associated with exposure to high background radiation. A matched case-control study was conducted using those who died of NPC during the period 1987-1995. Two controls were randomly selected for each case from those who died from causes other than malignancies and external causes. Cases and their controls were matched with respect to sex and the years of birth and death (±5 years). Study subjects' next-of-kin were interviewed using a standardized questionnaire to collect information on socioeconomic status, dietary habits, tobacco smoking and alcohol consumption, disease history, pesticide use, medical X-ray exposure, the family history of NPC and so on. We succeeded in interviewing 97 cases and 192 controls. Univariate conditional logistic regression analysis showed that NPC risk was associated with the consumption of salted fish, homemade pickles, and fermented soy beans, education levels, the history of chronic rhinitis, and the family history of NPC. Multivariate conditional logistic regression analysis revealed that education levels (Odds ratio (OR) for middle school or higher levels vs. no school education=3.8, 95% CI=1.2 to 11.8), salted fish intake (OR=3.2, 95% CI=1.7 to 6.1), the history of chronic rhinitis (OR=3.6, 95% CI=1.3 to 10.1), and the family history of NPC (OR=14.2, 95% CI=2.7 to 73.4) were independent risk factors of NPC. Tobacco smoking (OR=1.2, 95% CI=0.7 to 2.1), and alcohol consumption (OR=0.9, 95% CI=0.5 to 1.9) were not significantly related to NPC risk. The ORs of NPC risk comparing HBRA and a nearby control area before and after adjustment for the major risk determinants identified in the present study were 0.86 (95% CI=0.50 to 1.50) and 0.87 (95% CI=0.45 to 1.67), respectively. Salted fish intake was

  5. The Very High Background Radiation Area in Ramsar, Iran: Public Health Risk or Signal for a Regulatory Paradigm Shift?

    Energy Technology Data Exchange (ETDEWEB)

    Karam, P. Andrew [Univ. of Rochester, Rochester, NY (United States); Mortazavi, S.M. Javad [Rafsanjan Univ. of Medical Sciences (Iran, Islamic Republic of). Medical Physics Dept.

    2001-07-01

    Ramsar, a city on the Caspian Sea in northern Iran hosts the highest measured natural background radiation levels in the world. These are due to the local geology and hydrogeology and, in some places, deliver radiation doses far in excess of those recommended for radiation workers. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy/yr and the highest recorded doses are about 260 mGy/yr. These high radiation levels are due to the deposition of {sup 226}Ra in local rocks and, because these rocks are used in the construction of many local houses, interior radiation levels are often similar to those found outside. The presence of areas such as Ramsar raises an interesting public health policy question: Is it necessary to relocate the inhabitants to areas of lower natural background radiation levels in the interests of public health? According to the linear, no-threshold (LNT) hypothesis, there is no doubt that relocating the population of Ramsar will result in a reduction in cancer incidence. Therefore, under any reasonable policy based on the LNT hypothesis, the public health is best served by relocating many of Ramsar's inhabitants to other areas along the Caspian Sea. At present, there is no reliable epidemiological data on cancer incidence among the inhabitants of Ramsar's high background radiation areas (HBRAs), but local physicians feel that local cancer incidence rates are lower than in neighboring cities. Furthermore, preliminary results indicate that there is a statistically significant radio adaptation in the inhabitants of Ramsar. Interestingly, it seems that the frequency of chromosome aberrations in the lymphocytes of the inhabitants of Ramsar is no higher than the control areas. This important finding suggests that the cancer rate in Ramsar should be no higher than in other comparable parts of Iran. In other HBRAs such as Yangjiang, China it has been reported that mortality from all cancers and those from

  6. The Very High Background Radiation Area in Ramsar, Iran: Public Health Risk or Signal for a Regulatory Paradigm Shift?

    International Nuclear Information System (INIS)

    Karam, P. Andrew; Mortazavi, S.M. Javad

    2001-01-01

    Ramsar, a city on the Caspian Sea in northern Iran hosts the highest measured natural background radiation levels in the world. These are due to the local geology and hydrogeology and, in some places, deliver radiation doses far in excess of those recommended for radiation workers. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy/yr and the highest recorded doses are about 260 mGy/yr. These high radiation levels are due to the deposition of 226 Ra in local rocks and, because these rocks are used in the construction of many local houses, interior radiation levels are often similar to those found outside. The presence of areas such as Ramsar raises an interesting public health policy question: Is it necessary to relocate the inhabitants to areas of lower natural background radiation levels in the interests of public health? According to the linear, no-threshold (LNT) hypothesis, there is no doubt that relocating the population of Ramsar will result in a reduction in cancer incidence. Therefore, under any reasonable policy based on the LNT hypothesis, the public health is best served by relocating many of Ramsar's inhabitants to other areas along the Caspian Sea. At present, there is no reliable epidemiological data on cancer incidence among the inhabitants of Ramsar's high background radiation areas (HBRAs), but local physicians feel that local cancer incidence rates are lower than in neighboring cities. Furthermore, preliminary results indicate that there is a statistically significant radio adaptation in the inhabitants of Ramsar. Interestingly, it seems that the frequency of chromosome aberrations in the lymphocytes of the inhabitants of Ramsar is no higher than the control areas. This important finding suggests that the cancer rate in Ramsar should be no higher than in other comparable parts of Iran. In other HBRAs such as Yangjiang, China it has been reported that mortality from all cancers and those from leukemia, breast and

  7. A Fluorogenic TMP-tag for High Signal-to-Background Intracellular Live Cell Imaging

    Science.gov (United States)

    Jing, Chaoran

    2013-01-01

    Developed to compliment the use of fluorescent proteins in live cell imaging, chemical tags enjoy the benefit of modular incorporation of organic fluorophores, opening the possibility of high photon output and special photophysical properties. However, the theoretical challenge in using chemical tags as opposed to fluorescent proteins for high-resolution imaging is background noise from unbound and/or non-specifically bound ligand-fluorophore. We envisioned we could overcome this limit by engineering fluorogenic trimethoprim-based chemical tags (TMP-tags) in which the fluorophore is quenched until binding with E. coli dihydrofolate reductase (eDHFR) tagged protein displaces the quencher. Thus, we began by building a non-fluorogenic, covalent TMP-tag based on a proximity-induced reaction known to achieve rapid and specific labeling both in vitro and inside of living cells. Here we take the final step and render the covalent TMP-tag fluorogenic. In brief, we designed a trimeric TMP-fluorophore-quencher molecule (TMP-Q-Atto520) with the quencher attached to a leaving group that, upon TMP binding to eDHFR, would be cleaved by a cysteine residue (Cys) installed just outside the binding pocket of eDHFR. We present the in vitro experiments showing that the eDHFR:L28C nucleophile cleaves the TMP-Q-Atto520 rapidly and efficiently, resulting in covalent labeling and remarkable fluorescence enhancement. Most significantly, while only our initial design, TMP-Q-Atto520 achieved the demanding goal of not only labeling highly abundant, localized intracellular proteins, but also less abundant, more dynamic cytoplasmic proteins. These results suggest that fluorogenic TMP-tag can significantly impact highresolution live cell imaging and further establish the potential of proximity-induced reactivity and organic chemistry more broadly as part of the growing toolbox for synthetic biology and cell engineering. PMID:23745575

  8. High spin levels in 151Ho

    International Nuclear Information System (INIS)

    Gizon, J.; Gizon, A.; Andre, S.; Genevey, J.; Jastrzebski, J.; Kossakowski, R.; Moszinski, M.; Preibisz, Z.

    1981-02-01

    We report here on the first study of the level structure of 151 Ho. High spin levels in 151 Ho have been populated in the 141 Pr + 16 O and 144 Sm + 12 C reactions. The level structure has been established up to 6.6 MeV energy and the spins and particles determined up to 49/2 - . Most of the proposed level configurations can be explained by the coupling of hsub(11/2) protons to fsub(7/2) and/or hsub(9/2) neutrons. An isomer with 14 +- 3 ns half-life and a delayed gamma multiplicity equal to 17 +- 2 has been found. Its spin is larger than 57/2 h units

  9. Disposal of high-level radioactive waste

    International Nuclear Information System (INIS)

    Glasby, G.P.

    1977-01-01

    Although controversy surrounding the possible introduction of nuclear power into New Zealand has raised many points including radiation hazards, reactor safety, capital costs, sources of uranium and earthquake risks on the one hand versus energy conservation and alternative sources of energy on the other, one problem remains paramount and is of global significance - the storage and dumping of the high-level radioactive wastes of the reactor core. The generation of abundant supplies of energy now in return for the storage of these long-lived highly radioactive wastes has been dubbed the so-called Faustian bargain. This article discusses the growth of the nuclear industry and its implications to high-level waste disposal particularly in the deep-sea bed. (auth.)

  10. A flat Universe from high-resolution maps of the cosmic microwave background radiation

    Science.gov (United States)

    de Bernardis P; Ade; Bock; Bond; Borrill; Boscaleri; Coble; Crill; De Gasperis G; Farese; Ferreira; Ganga; Giacometti; Hivon; Hristov; Iacoangeli; Jaffe; Lange; Martinis; Masi; Mason; Mauskopf; Melchiorri; Miglio; Montroy; Netterfield

    2000-04-27

    The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73 K cosmic microwave background. Tiny inhomogeneities in the early Universe left their imprint on the microwave background in the form of small anisotropies in its temperature. These anisotropies contain information about basic cosmological parameters, particularly the total energy density and curvature of the Universe. Here we report the first images of resolved structure in the microwave background anisotropies over a significant part of the sky. Maps at four frequencies clearly distinguish the microwave background from foreground emission. We compute the angular power spectrum of the microwave background, and find a peak at Legendre multipole Ipeak = (197 +/- 6), with an amplitude delta T200 = (69 +/- 8) microK. This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favoured by standard inflationary models.

  11. Profiles of doses to the population living in the high background radiation areas in Kerala, India

    Energy Technology Data Exchange (ETDEWEB)

    Chougaonkar, M.P. E-mail: mpckar@hotmail.com; Eappen, K.P.; Ramachandran, T.V.; Shetty, P.G.; Mayya, Y.S.; Sadasivan, S.; Venkat Raj, V

    2004-07-01

    A sample study of the profiles of radiation exposures to the populations living in the high background radiation areas (HBRAs) of the monazite-bearing region in Kerala, India, has been conducted by monitoring 200 dwellings selected from two villages in this region. Each of these dwellings was monitored for 1 year and the study lasted for a period of 2 years. The indoor gamma ray dose measurements were carried out using thermo luminescent dosimeters (TLDs) and the inhalation doses due to radon, thoron and their progenies were monitored using solid-state nuclear track detector (SSNTD) based twin-cup dosimeters. Outdoor gamma ray dose measurements were carried out using Geiger Muller (GM) tube based survey meters. Annual effective doses were computed, using occupancy factors of 0.8 and 0.2, respectively, for indoor and outdoor, by adding the three components. Occupants of 41.6% of the houses surveyed were observed to receive the annual effective doses ranging between 0.5 and 5 mSv/a, 41.6% between 5 and 10 mSv/a, 10.2% between 10 and 15 mSv/a and 6.6% greater than 15 mSv/a. The inhalation component was generally smaller than the external gamma ray component and on an average it was found to constitute about 30% of the total dose. The paper presents the details of the methodology adopted and the analysis of the results.

  12. Experimental test of the background rejection, through imaging capability, of a highly segmented AGATA germanium detector

    International Nuclear Information System (INIS)

    Doncel, M.; Recchia, F.; Quintana, B.; Gadea, A.; Farnea, E.

    2010-01-01

    The development of highly segmented germanium detectors as well as the algorithms to identify the position of the interaction within the crystal opens the possibility to locate the γ-ray source using Compton imaging algorithms. While the Compton-suppression shield, coupled to the germanium detector in conventional arrays, works also as an active filter against the γ rays originated outside the target, the new generation of position sensitive γ-ray detector arrays has to fully rely on tracking capabilities for this purpose. In specific experimental conditions, as the ones foreseen at radioactive beam facilities, the ability to discriminate background radiation improves the sensitivity of the gamma spectrometer. In this work we present the results of a measurement performed at the Laboratori Nazionali di Legnaro (LNL) aiming the evaluation of the AGATA detector capabilities to discriminate the origin of the γ rays on an event-by-event basis. It will be shown that, exploiting the Compton scattering formula, it is possible to track back γ rays coming from different positions, assigning them to specific emitting locations. These imaging capabilities are quantified for a single crystal AGATA detector.

  13. Study of thorium uptake by inhabitants of a high background radiation area

    International Nuclear Information System (INIS)

    Melo, D.R.; Lipsztein, J.L.; Juliao, L.M.Q.C.; Lourenco, M.C.; Lauria, D.

    2002-01-01

    Buena, located in the North of Rio de Janeiro, is characterized by its high natural radiation background, due to large deposits of monazite sand. The foodstuffs consumed by the population are basically composed of local products, which contain significant amounts of thorium. The analysis of complete cooked meals have shown an average daily intake of 18 mBq.d -1 of 232 Th and 189 mBq.d -1 of 228 Th. The average urine to feces ratio of 232 Th from samples of volunteers was found equal to 7.5x10 -2 . The comparison of the experimental data with the predicted urine to feces ratios derived using the biokinetic model for thorium described by the ICRP publication 69 and simulating inhalation and ingestion separately, lead to the conclusion that the thorium intake is a combination of inhalation and ingestion. The clearance rate of thorium of monazite in lungs has apparently behaved as Type M compound. Inhalation is the biggest contributor for the committed effective dose due to thorium internal exposure. (author)

  14. High pulse number thermal shock tests on tungsten with steady state particle background

    Science.gov (United States)

    Wirtz, M.; Kreter, A.; Linke, J.; Loewenhoff, Th; Pintsuk, G.; Sergienko, G.; Steudel, I.; Unterberg, B.; Wessel, E.

    2017-12-01

    Thermal fatigue of metallic materials, which will be exposed to severe environmental conditions e.g. plasma facing materials in future fusion reactors, is an important issue in order to predict the life time of complete wall components. Therefore experiments in the linear plasma device PSI-2 were performed to investigate the synergistic effects of high pulse number thermal shock events (L = 0.38 GW m-2, Δt = 0.5 ms) and stationary D/He (6%) plasma particle background on the thermal fatigue behavior of tungsten. Similar to experiments with pure thermal loads, the induced microstructural and surface modifications such as recrystallization and roughening as well as crack formation become more pronounced with increasing number of thermal shock events. However, the amount of damage significantly increases for synergistic loads showing severe surface roughening, plastic deformation and erosion resulting from the degradation of the mechanical properties caused by bombardment and diffusion of D/He to the surface and the bulk of the material. Additionally, D/He induced blistering and bubble formation were observed for all tested samples, which could change the thermal and mechanical properties of near surface regions.

  15. A highly sensitive technique for detecting catalytically active nanoparticles against a background of general workplace aerosols

    International Nuclear Information System (INIS)

    Neubauer, N; Weis, F; Seipenbusch, M; Kasper, G; Binder, A

    2011-01-01

    A new measurement technique was studied using catalysis to specifically detect airborne nanoparticles in presence of background particles in the workplace air. Catalytically active nanoparticles produced by spark discharge were used as aerosol catalysts. According to these particles suitable catalytic test reactions were chosen and investigated by two different approaches: catalysis on airborne nanoparticles and catalysis on deposited nanoparticles. The results indicate that catalysis is applicable for the specific measurement of nanoparticles in the workplace air. Catalysis on airborne particles is suitable for the specific detection of very active nanoparticles, e.g. platinum or nickel, at high concentrations of about 10 7 /cm 3 . The approach of catalysis on deposited particles is better suited for nanoparticle aerosols at low concentrations, for slow catalytic reactions or less active nanoparticles like iron oxide (Fe 2 O 3 ). On the basis of the experimental results detection limits in the range of μg or even ng were calculated which assure the good potential of catalysis for the specific detection of nanoparticles in the workplace air based on their catalytic activity.

  16. Chromosome translocation in residents of the high background radiation areas in southern China

    International Nuclear Information System (INIS)

    Hayata, Isamu; Minamihisamatsu, Masako; Wang Chunyan; Wei Zhang; Chen Deqing; Morishima, Hiroshige; Yuan Yongling; Wei Luxin; Sugahara, Tsutomu

    2000-01-01

    We performed a cytogenetical study using chromosome painting analysis on 9 residents of the naturally high background radiation areas (HBRA) and 8 residents of the control areas in southern China. The estimated dose (air kerma) of each resident measured by an electric pocket dosimeter showed 2.20-4.23 mGy/year in HBRA and 0.56-0.70 mGy/year in the control areas. A total of 14,096 cells (1,566 cells/case) in the former and 17,522 cells (2,190 cells/case) in the latter were analyzed. Children, both in HBRA and in the control areas, had translocations at low frequencies. The frequency of translocations among elder individuals varied widely and it was not possible to detect dose effect although it was detected in dicentrics. The effect of radiation on the induction of chromosome aberrations, which have a statistically potential risk of causing malignant or congenital diseases, seems to be less significant than those of metabolic factors and/or mutagenic agents (excluding radiation) even in HBRA in China. (author)

  17. Python based high-level synthesis compiler

    Science.gov (United States)

    Cieszewski, Radosław; Pozniak, Krzysztof; Romaniuk, Ryszard

    2014-11-01

    This paper presents a python based High-Level synthesis (HLS) compiler. The compiler interprets an algorithmic description of a desired behavior written in Python and map it to VHDL. FPGA combines many benefits of both software and ASIC implementations. Like software, the mapped circuit is flexible, and can be reconfigured over the lifetime of the system. FPGAs therefore have the potential to achieve far greater performance than software as a result of bypassing the fetch-decode-execute operations of traditional processors, and possibly exploiting a greater level of parallelism. Creating parallel programs implemented in FPGAs is not trivial. This article describes design, implementation and first results of created Python based compiler.

  18. High-level waste processing and disposal

    International Nuclear Information System (INIS)

    Crandall, J.L.; Krause, H.; Sombret, C.; Uematsu, K.

    1984-01-01

    The national high-level waste disposal plans for France, the Federal Republic of Germany, Japan, and the United States are covered. Three conclusions are reached. The first conclusion is that an excellent technology already exists for high-level waste disposal. With appropriate packaging, spent fuel seems to be an acceptable waste form. Borosilicate glass reprocessing waste forms are well understood, in production in France, and scheduled for production in the next few years in a number of other countries. For final disposal, a number of candidate geological repository sites have been identified and several demonstration sites opened. The second conclusion is that adequate financing and a legal basis for waste disposal are in place in most countries. Costs of high-level waste disposal will probably add about 5 to 10% to the costs of nuclear electric power. The third conclusion is less optimistic. Political problems remain formidable in highly conservative regulations, in qualifying a final disposal site, and in securing acceptable transport routes

  19. Low risk of pulmonary tuberculosis of residents in high background radiation area, Yangjiang, China

    International Nuclear Information System (INIS)

    Li Xiaojuan; Sun Quanfu

    2006-01-01

    Objective: To examine the pulmonary tuberculosis mortality risk of the residents in high background radiation area (HBRA), Yangjiang, China. Methods: A cohort including 89 694 persons in HBRA and 35 385 persons in control area (CA) has been established since 1979. Person-year tables based on classified variables including sex, attained age, follow-up calendar year, and dose-rate group (high, intermediate, and low in HBRA, and control group) were tabulated using DATAB in EPICURE. Poisson regression analysis was used to estimate the relative risks (RR) of infectious and parasitic disease especially for pulmonary tuberculosis. Cumulative dose for each cohort member was obtained. Results: Two million person-years were accumulated by follow-up and 612 cases of pulmonary tuberculosis ascertained. Compared with risk in the control area, statistically significant lower risk of pulmonary tuberculosis was observed in HBRA among those who aged 60 years and over; markedly decreased risk occurred among males; no significant difference was found among the 6 follow-up stages, two subregions in the HBRA, or different diagnostic facilities. A statistically significantly negative dose-response was observed (P<0.001), the higher accumulative dose, the lower dose the pulmonary tuberculosis mortality risk. Its excess relative risk (ERR/Sv) was estimated to be -1.09 (95% CI: -1.34, -0.85). No established risk factors could explain this lower risk. Conclusions: The mortality of puhnonary tuberculosis among residents in HBRA who were chronically exposed to low-dose radiation was statistically significantly lower than that in the control area, and a significant dose-response relationship was observed, which probably resulted from the immunoenhancement of low dose radiation. (authors)

  20. Assessment of radiation background level of Shandong basin in east line of northward rerouting of southern river

    International Nuclear Information System (INIS)

    Deng Daping; Xu Jiaang; Zhu Jianguo; Chen Yingmin; Lu Feng; Song Gang; Cao Jingli

    2007-01-01

    Objective: To assess the radiation background levels of Shandong basin in east line of northward rerouting of southern river. Methods: The activity concentrations of gross-alpha, gross-beta, 137 Cs, 238 U, 232 Th, 40 K, 226 Ra and 90 Sr in the samples were measured by national standard methods respectively. The values of the dose conversion factor given by UNSCEAR 2000 were adopted for dose estimation. Results: The average activity concentrations of gross-alpha, gross-beta, 137 Cs, 238 U, 232 Th, 40 K, 226 Ra and 90 Sr in the samples were pooled in order to analyze dose estimation. The committed effective doses of the 226 Ra, 238 U, 90 Sr, 232 Th and 137 Cs from lake water for residents are 1.46, 4.95 x 10 -1 , 1.24 x 10 -1 , 2.58 x 10 -2 and 7.93 x 10 -3 μSv per year respectively. The committed effective doses of the 226 Ra, 238 U and 90 Sr from cyprinoid fish are 5.49 x 10 -2 , 3.69 x 10 -2 and 1.77 x 10 -2 μSv per year respectively. Conclusions: The results show that the average activity concentrations of gross-alpha, gross-beta, 137 Cs, 238 U, 232 Th, 40 K, 226 Ra and 90 Sr in the samples from Shandong basin of northward rerouting of southern river are within the background levels. And in the main lake basin, the estimated exposures of public caused by the radionuclide in water and cyprinoid fish are so low that they can be ignored unless there ate some radioactive contamination in the future. (authors)

  1. DUACS: Toward High Resolution Sea Level Products

    Science.gov (United States)

    Faugere, Y.; Gerald, D.; Ubelmann, C.; Claire, D.; Pujol, M. I.; Antoine, D.; Desjonqueres, J. D.; Picot, N.

    2016-12-01

    The DUACS system produces, as part of the CNES/SALP project, and the Copernicus Marine Environment and Monitoring Service, high quality multimission altimetry Sea Level products for oceanographic applications, climate forecasting centers, geophysic and biology communities... These products consist in directly usable and easy to manipulate Level 3 (along-track cross-calibrated SLA) and Level 4 products (multiple sensors merged as maps or time series) and are available in global and regional version (Mediterranean Sea, Arctic, European Shelves …).The quality of the products is today limited by the altimeter technology "Low Resolution Mode" (LRM), and the lack of available observations. The launch of 2 new satellites in 2016, Jason-3 and Sentinel-3A, opens new perspectives. Using the global Synthetic Aperture Radar mode (SARM) coverage of S3A and optimizing the LRM altimeter processing (retracking, editing, ...) will allow us to fully exploit the fine-scale content of the altimetric missions. Thanks to this increase of real time altimetry observations we will also be able to improve Level-4 products by combining these new Level-3 products and new mapping methodology, such as dynamic interpolation. Finally these improvements will benefit to downstream products : geostrophic currents, Lagrangian products, eddy atlas… Overcoming all these challenges will provide major upgrades of Sea Level products to better fulfill user needs.

  2. A study of the effect of flight density and background noise on V/STOL acceptability. [effective perceived noise level as measure of annoyance

    Science.gov (United States)

    Sternfeld, H., Jr.; Hinterkeuser, E. G.; Hackman, R. B.; Davis, J.

    1974-01-01

    A study was conducted in which test subjects evaluated the sounds of a helicopter, a turbofan STOL and a turbojet airplane while engaged in work and leisure activities. Exposure to a high repetitive density of the aircraft sounds did not make the individual sounds more annoying but did create an unacceptable environment. The application of a time duration term to db(A) resulted in a measure which compared favorably with EPNL as a predictor of annoyance. Temporal variations in background noise level had no significant effect on the rated annoyance.

  3. Cermets for high level waste containment

    International Nuclear Information System (INIS)

    Aaron, W.S.; Quinby, T.C.; Kobisk, E.H.

    1978-01-01

    Cermet materials are currently under investigation as an alternate for the primary containment of high level wastes. The cermet in this study is an iron--nickel base metal matrix containing uniformly dispersed, micron-size fission product oxides, aluminosilicates, and titanates. Cermets possess high thermal conductivity, and typical waste loading of 70 wt % with volume reduction factors of 2 to 200 and low processing volatility losses have been realized. Preliminary leach studies indicate a leach resistance comparable to other candidate waste forms; however, more quantitative data are required. Actual waste studies have begun on NFS Acid Thorex, SRP dried sludge and fresh, unneutralized SRP process wastes

  4. Timing of High-level Waste Disposal

    International Nuclear Information System (INIS)

    2008-01-01

    This study identifies key factors influencing the timing of high-level waste (HLW) disposal and examines how social acceptability, technical soundness, environmental responsibility and economic feasibility impact on national strategies for HLW management and disposal. Based on case study analyses, it also presents the strategic approaches adopted in a number of national policies to address public concerns and civil society requirements regarding long-term stewardship of high-level radioactive waste. The findings and conclusions of the study confirm the importance of informing all stakeholders and involving them in the decision-making process in order to implement HLW disposal strategies successfully. This study will be of considerable interest to nuclear energy policy makers and analysts as well as to experts in the area of radioactive waste management and disposal. (author)

  5. High-Level Waste Melter Study Report

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Joseph M.; Bickford, Dennis F.; Day, Delbert E.; Kim, Dong-Sang; Lambert, Steven L.; Marra, Sharon L.; Peeler, David K.; Strachan, Denis M.; Triplett, Mark B.; Vienna, John D.; Wittman, Richard S.

    2001-07-13

    At the Hanford Site in Richland, Washington, the path to site cleanup involves vitrification of the majority of the wastes that currently reside in large underground tanks. A Joule-heated glass melter is the equipment of choice for vitrifying the high-level fraction of these wastes. Even though this technology has general national and international acceptance, opportunities may exist to improve or change the technology to reduce the enormous cost of accomplishing the mission of site cleanup. Consequently, the U.S. Department of Energy requested the staff of the Tanks Focus Area to review immobilization technologies, waste forms, and modifications to requirements for solidification of the high-level waste fraction at Hanford to determine what aspects could affect cost reductions with reasonable long-term risk. The results of this study are summarized in this report.

  6. High-level radioactive wastes. Supplement 1

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, L.H. (ed.)

    1984-09-01

    This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations.

  7. Decommissioning high-level waste surface facilities

    International Nuclear Information System (INIS)

    1978-04-01

    The protective storage, entombment and dismantlement options of decommissioning a High-Level Waste Surface Facility (HLWSF) was investigated. A reference conceptual design for the facility was developed based on the designs of similar facilities. State-of-the-art decommissioning technologies were identified. Program plans and cost estimates for decommissioning the reference conceptual designs were developed. Good engineering design concepts were on the basis of this work identified

  8. High sensitivity isotope analysis with a 252Cf--235U fueled subcritical multiplier and low background photon detector systems

    International Nuclear Information System (INIS)

    Wogman, N.A.; Rieck, H.G. Jr.; Laul, J.C.; MacMurdo, K.W.

    1976-09-01

    A 252 Cf activation analysis facility has been developed for routine multielement analysis of a wide variety of solid and liquid samples. The facility contains six sources of 252 Cf totaling slightly over 100 mg. These sources are placed in a 93 percent 235 U-enriched uranium core which is subcritical with a K effective of 0.985 (multiplication factor of 66). The system produces a thermal flux on the order of 10 +1 neutrons per square centimeter per second. A pneumatic rabbit system permits automatic irradiation, decay, and counting regimes to be performed unattended on the samples. The activated isotopes are analyzed through their photon emissions with state-of-the-art intrinsic Ge detectors, Ge(Li) detectors, and NaI(Tl) multidimensional gamma ray spectrometers. High efficiency (25 percent), low background, anticoincidence shielded Ge(Li) gamma ray detector systems have been constructed to provide the lowest possible background, yet maintain a peak to Compton ratio of greater than 1000 to 1. The multidimensional gamma ray spectrometer systems are composed of 23 cm diameter x 20 cm thick NaI(Tl) crystals surrounded by NaI(Tl) anticoincidence shields. The detection limits for over 65 elements have been determined for this system. Over 40 elements are detectable at the 1 part per million level at a precision of +-10 percent

  9. A prospective study on congenital malformations in the high background radiation areas of Kerala

    International Nuclear Information System (INIS)

    Jaikrishan, G.; Sudheer, K.R.; Andrews, V.J.; Koya, P.K.M.; Cheriyan, V.D.; Seshadri, M.

    2010-01-01

    Hospital based epidemiological study on congenital anomalies carried out in the high level natural radiation (HLNR) areas of southern Kerala since 1995 to assess the hereditary effects, if any, of HLNR is reported here. Thorium, Uranium to a limited extent, and corresponding decay products in the natural deposits of monazite sand is the source of radiation. HLNR and normal level natural radiation (NLNR) areas are interwoven due to the patchy and non-uniform distribution of monazite in the region. Areas with a mean dose of more than 1.5 mGy/year were treated as HLNR areas and those with 1.5 mGy/year or less, as NLNR. High population density, limited migration, ethnic diversity, good literacy, health awareness, institutionalized births and acceptance of small family norm are some of the key features of the population. The comparison of individual malformation in HLNR and NLNR areas are presented and efforts are on to accrue sufficient sample size to enable the comparison

  10. Background observations on the SMM high energy monitor at energies greater than 10 MeV

    Science.gov (United States)

    Forrest, D. J.

    1989-01-01

    The background rate in any gamma ray detector on a spacecraft in near-earth orbit is strongly influenced by the primary cosmic ray flux at the spacecraft's position. Although the direct counting of the primary cosmic rays can be rejected by anticoincident shields, secondary production cannot be. Secondary production of gamma rays and neutrons in the instrument, the spacecraft, and the earth's atmospheric are recorded as background. A 30 day data base of 65.5 second records has been used to show that some of the background rates observed on the Gamma Ray Spectrometer can be ordered to a precision on the order of 1 percent This ordering is done with only two parameters, namely the cosmic ray vertical cutoff rigidity and the instrument's pointing angle with respect to the earth's center. This result sets limits on any instrumental instability and also on any temporal or spatial changes in the background radiation field.

  11. Performance of the CMS High Level Trigger

    CERN Document Server

    Perrotta, Andrea

    2015-01-01

    The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increases in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. The increase in the number of interactions per bunch crossing, on average 25 in 2012, and expected to be around 40 in Run II, will be an additional complication. We present here the expected performance of the main triggers that will be used during the 2015 data taking campaign, paying particular attention to the new approaches that have been developed to cope with the challenges of the new run. This includes improvements in HLT electron and photon reconstruction as well as better performing muon triggers. We will also present the performance of the improved trac...

  12. Case-control study of cancer deaths in high background radiation areas of China

    International Nuclear Information System (INIS)

    Tao Zufan; Cha Yongru; Zhou Shunyuan

    1989-01-01

    This paper presents the results of a case-control study of deaths from liver, stomach and lung cancers in the high background radiation areas (HBRA) in Yangjiang County and neighboring control areas (CA). The purpose of this study was to explore the probable relationship between the cancer deaths and the environmental mutation-related factors in the two areas, so that the role of elevated natural radiation in cancer mortality could be properly ascertained. The studied numbers of cases of liver, stomach and lung cancers were 64, 28 and 17 in HBRA, and 75, 36 and 13 in CA, respectively. The proportion of the number of cases to that of the controls was 1:1 for liver cancer and 1:2 for cancers of stomach and lung. The factors studied included pesticide, smoking, alcohol consumption, medical X-ray exposure, diet, and the socioeconomic status, such as occupation, education, economic income, living space etc. The data for this study were collected through interviewing. The data collected were analysed by methods of matched and unmatched studies. The results expressed by odds ratio (OR) show that there is no significant between most factors studied and cancer deaths, although the associations of desths from stomach cancer with drinking water of nonwell source and of lung cancer with alcohol consumption in HBRA, and the associations of liver cancer deaths with occupations involving poisonous and noxious substances, pesticide and alcohol, and of lung cancer with pesticide and lower family income in CA can be found. This study has provided some clues for explaining the difference in cancer mortalities between HBRA and CA

  13. Background noise levels measured in the NASA Lewis 9- by 15-foot low-speed wind tunnel

    Science.gov (United States)

    Woodward, Richard P.; Dittmar, James H.; Hall, David G.; Kee-Bowling, Bonnie

    1994-01-01

    The acoustic capability of the NASA Lewis 9 by 15 Foot Low Speed Wind Tunnel has been significantly improved by reducing the background noise levels measured by in-flow microphones. This was accomplished by incorporating streamlined microphone holders having a profile developed by researchers at the NASA Ames Research Center. These new holders were fabricated for fixed mounting on the tunnel wall and for an axially traversing microphone probe which was mounted to the tunnel floor. Measured in-flow noise levels in the tunnel test section were reduced by about 10 dB with the new microphone holders compared with those measured with the older, less refined microphone holders. Wake interference patterns between fixed wall microphones were measured and resulted in preferred placement patterns for these microphones to minimize these effects. Acoustic data from a model turbofan operating in the tunnel test section showed that results for the fixed and translating microphones were equivalent for common azimuthal angles, suggesting that the translating microphone probe, with its significantly greater angular resolution, is preferred for sideline noise measurements. Fixed microphones can provide a local check on the traversing microphone data quality, and record acoustic performance at other azimuthal angles.

  14. The high level vibration test program

    International Nuclear Information System (INIS)

    Hofmayer, C.H.; Curreri, J.R.; Park, Y.J.; Kato, W.Y.; Kawakami, S.

    1989-01-01

    As part of cooperative agreements between the US and Japan, tests have been performed on the seismic vibration table at the Tadotsu Engineering Laboratory of Nuclear Power Engineering Test Center (NUPEC) in Japan. The objective of the test program was to use the NUPEC vibration table to drive large diameter nuclear power piping to substantial plastic strain with an earthquake excitation and to compare the results with state-of-the-art analysis of the problem. The test model was subjected to a maximum acceleration well beyond what nuclear power plants are designed to withstand. A modified earthquake excitation was applied and the excitation level was increased carefully to minimize the cumulative fatigue damage due to the intermediate level excitations. Since the piping was pressurized, and the high level earthquake excitation was repeated several times, it was possible to investigate the effects of ratchetting and fatigue as well. Elastic and inelastic seismic response behavior of the test model was measured in a number of test runs with an increasing excitation input level up to the limit of the vibration table. In the maximum input condition, large dynamic plastic strains were obtained in the piping. Crack initiation was detected following the second maximum excitation run. Crack growth was carefully monitored during the next two additional maximum excitation runs. The final test resulted in a maximum crack depth of approximately 94% of the wall thickness. The HLVT (high level vibration test) program has enhanced understanding of the behavior of piping systems under severe earthquake loading. As in other tests to failure of piping components, it has demonstrated significant seismic margin in nuclear power plant piping

  15. Natural radionuclides in environmental media: a review of natural levels of radioactivity and background radiation levels and an assessment of factors affecting these levels

    International Nuclear Information System (INIS)

    Bradley, E.J.

    1993-01-01

    A review of the literature has been carried out to assemble the information available on the levels of naturally-occurring radionuclides in environmental media in the UK. Some data from other countries are included for comparison. The data are compiled on the basis of geographical origin into five main sectors: air; waters; vegetation; soils, rocks and sediments; and foodstuffs. A summary table is provided for each main section. (author)

  16. Ramifications of defining high-level waste

    International Nuclear Information System (INIS)

    Wood, D.E.; Campbell, M.H.; Shupe, M.W.

    1987-01-01

    The Nuclear Regulatory Commission (NRC) is considering rule making to provide a concentration-based definition of high-level waste (HLW) under authority derived from the Nuclear Waste Policy Act (NWPA) of 1982 and the Low Level Waste Policy Amendments Act of 1985. The Department of Energy (DOE), which has the responsibility to dispose of certain kinds of commercial waste, is supporting development of a risk-based classification system by the Oak Ridge National Laboratory to assist in developing and implementing the NRC rule. The system is two dimensional, with the axes based on the phrases highly radioactive and requires permanent isolation in the definition of HLW in the NWPA. Defining HLW will reduce the ambiguity in the present source-based definition by providing concentration limits to establish which materials are to be called HLW. The system allows the possibility of greater-confinement disposal for some wastes which do not require the degree of isolation provided by a repository. The definition of HLW will provide a firm basis for waste processing options which involve partitioning of waste into a high-activity stream for repository disposal, and a low-activity stream for disposal elsewhere. Several possible classification systems have been derived and the characteristics of each are discussed. The Defense High Level Waste Technology Lead Office at DOE - Richland Operations Office, supported by Rockwell Hanford Operations, has coordinated reviews of the ORNL work by a technical peer review group and other DOE offices. The reviews produced several recommendations and identified several issues to be addressed in the NRC rule making. 10 references, 3 figures

  17. Intergenerational ethics of high level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kunihiko [Nagoya Univ., Graduate School of Engineering, Nagoya, Aichi (Japan); Nasu, Akiko; Maruyama, Yoshihiro [Shibaura Inst. of Tech., Tokyo (Japan)

    2003-03-01

    The validity of intergenerational ethics on the geological disposal of high level radioactive waste originating from nuclear power plants was studied. The result of the study on geological disposal technology showed that the current method of disposal can be judged to be scientifically reliable for several hundred years and the radioactivity level will be less than one tenth of the tolerable amount after 1,000 years or more. This implies that the consideration of intergenerational ethics of geological disposal is meaningless. Ethics developed in western society states that the consent of people in the future is necessary if the disposal has influence on them. Moreover, the ethics depends on generally accepted ideas in western society and preconceptions based on racism and sexism. The irrationality becomes clearer by comparing the dangers of the exhaustion of natural resources and pollution from harmful substances in a recycling society. (author)

  18. Management of high level radioactive waste

    International Nuclear Information System (INIS)

    Redon, A.; Mamelle, J.; Chambon, M.

    1977-01-01

    The world wide needs in reprocessing will reach the value of 10.000 t/y of irradiated fuels, in the mid of the 80's. Several countries will have planned, in their nuclear programme, the construction of reprocessing plants with a 1500 t/y capacity, corresponding to 50.000 MWe installed. At such a level, the solidification of the radioactive waste will become imperative. For this reason, all efforts, in France, have been directed towards the realization of industrial plants able of solidifying the fission products as a glassy material. The advantages of this decision, and the reasons for it are presented. The continuing development work, and the conditions and methods of storing the high-level wastes prior to solidification, and of the interim storage (for thermal decay) and the ultimate disposal after solidification are described [fr

  19. Intergenerational ethics of high level radioactive waste

    International Nuclear Information System (INIS)

    Takeda, Kunihiko; Nasu, Akiko; Maruyama, Yoshihiro

    2003-01-01

    The validity of intergenerational ethics on the geological disposal of high level radioactive waste originating from nuclear power plants was studied. The result of the study on geological disposal technology showed that the current method of disposal can be judged to be scientifically reliable for several hundred years and the radioactivity level will be less than one tenth of the tolerable amount after 1,000 years or more. This implies that the consideration of intergenerational ethics of geological disposal is meaningless. Ethics developed in western society states that the consent of people in the future is necessary if the disposal has influence on them. Moreover, the ethics depends on generally accepted ideas in western society and preconceptions based on racism and sexism. The irrationality becomes clearer by comparing the dangers of the exhaustion of natural resources and pollution from harmful substances in a recycling society. (author)

  20. The CMS High Level Trigger System

    CERN Document Server

    Afaq, A; Bauer, G; Biery, K; Boyer, V; Branson, J; Brett, A; Cano, E; Carboni, A; Cheung, H; Ciganek, M; Cittolin, S; Dagenhart, W; Erhan, S; Gigi, D; Glege, F; Gómez-Reino, Robert; Gulmini, M; Gutiérrez-Mlot, E; Gutleber, J; Jacobs, C; Kim, J C; Klute, M; Kowalkowski, J; Lipeles, E; Lopez-Perez, Juan Antonio; Maron, G; Meijers, F; Meschi, E; Moser, R; Murray, S; Oh, A; Orsini, L; Paus, C; Petrucci, A; Pieri, M; Pollet, L; Rácz, A; Sakulin, H; Sani, M; Schieferdecker, P; Schwick, C; Sexton-Kennedy, E; Sumorok, K; Suzuki, I; Tsirigkas, D; Varela, J

    2007-01-01

    The CMS Data Acquisition (DAQ) System relies on a purely software driven High Level Trigger (HLT) to reduce the full Level-1 accept rate of 100 kHz to approximately 100 Hz for archiving and later offline analysis. The HLT operates on the full information of events assembled by an event builder collecting detector data from the CMS front-end systems. The HLT software consists of a sequence of reconstruction and filtering modules executed on a farm of O(1000) CPUs built from commodity hardware. This paper presents the architecture of the CMS HLT, which integrates the CMS reconstruction framework in the online environment. The mechanisms to configure, control, and monitor the Filter Farm and the procedures to validate the filtering code within the DAQ environment are described.

  1. High level waste fixation in cermet form

    International Nuclear Information System (INIS)

    Kobisk, E.H.; Aaron, W.S.; Quinby, T.C.; Ramey, D.W.

    1981-01-01

    Commercial and defense high level waste fixation in cermet form is being studied by personnel of the Isotopes Research Materials Laboratory, Solid State Division (ORNL). As a corollary to earlier research and development in forming high density ceramic and cermet rods, disks, and other shapes using separated isotopes, similar chemical and physical processing methods have been applied to synthetic and real waste fixation. Generally, experimental products resulting from this approach have shown physical and chemical characteristics which are deemed suitable for long-term storage, shipping, corrosive environments, high temperature environments, high waste loading, decay heat dissipation, and radiation damage. Although leach tests are not conclusive, what little comparative data are available show cermet to withstand hydrothermal conditions in water and brine solutions. The Soxhlet leach test, using radioactive cesium as a tracer, showed that leaching of cermet was about X100 less than that of 78 to 68 glass. Using essentially uncooled, untreated waste, cermet fixation was found to accommodate up to 75% waste loading and yet, because of its high thermal conductivity, a monolith of 0.6 m diameter and 3.3 m-length would have only a maximum centerline temperature of 29 K above the ambient value

  2. Liquid level measurement in high level nuclear waste slurries

    International Nuclear Information System (INIS)

    Weeks, G.E.; Heckendorn, F.M.; Postles, R.L.

    1990-01-01

    Accurate liquid level measurement has been a difficult problem to solve for the Defense Waste Processing Facility (DWPF). The nuclear waste sludge tends to plug or degrade most commercially available liquid-level measurement sensors. A liquid-level measurement system that meets demanding accuracy requirements for the DWPF has been developed. The system uses a pneumatic 1:1 pressure repeater as a sensor and a computerized error correction system. 2 figs

  3. Service Oriented Architecture for High Level Applications

    International Nuclear Information System (INIS)

    Chu, P.

    2012-01-01

    Standalone high level applications often suffer from poor performance and reliability due to lengthy initialization, heavy computation and rapid graphical update. Service-oriented architecture (SOA) is trying to separate the initialization and computation from applications and to distribute such work to various service providers. Heavy computation such as beam tracking will be done periodically on a dedicated server and data will be available to client applications at all time. Industrial standard service architecture can help to improve the performance, reliability and maintainability of the service. Robustness will also be improved by reducing the complexity of individual client applications.

  4. The ARES High-level Intermediate Representation

    Energy Technology Data Exchange (ETDEWEB)

    Moss, Nicholas David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-03

    The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. This highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.

  5. Role of Family Background, Student Behaviors, and School-Related Beliefs in Predicting High School Dropout

    Science.gov (United States)

    Parr, Alyssa K.; Bonitz, Verena S.

    2015-01-01

    The authors' purpose was to test a parsimonious model derived from social cognitive career theory (R. W. Lent, S. D. Brown, & G. Hackett, 1994) and expectancy value theory (J. S. Eccles & A. Wigfield, 2002) that integrates groups of variables (demographic background, student behaviors, and school-related beliefs) with the goal of…

  6. Exposure to unusually high indoor radon levels

    International Nuclear Information System (INIS)

    Rasheed, F.N.

    1993-01-01

    Unusually high indoor radon concentrations were reported in a small village in western Tyrol, Austria. The authors have measured the seasonal course of indoor radon concentrations in 390 houses of this village. 71% of houses in winter and 33% in summer, showed radon values on the ground floor above the Austrian action level of 400 Bq/cm 3 . This proportion results in an unusually high indoor radon exposure of the population. The radon source was an 8,700-year-old rock slide of granite gneiss, the largest of the alpine crystalline rocks. It has a strong emanating power because its rocks are heavily fractured and show a slightly increased uranium content. Previous reports show increased lung cancer mortality, myeloid leukemia, kidney cancer, melanoma, and prostate cancer resulting from indoor radon exposure. However, many studies fail to provide accurate information on indoor radon concentrations, classifying them merely as low, intermediate, and high, or they record only minor increases in indoor radon concentrations. Mortality data for 1970-91 were used to calculate age and sex standardized mortality rates (SMR) for 51 sites of carcinoma. The total population of Tyrol were controls. A significantly higher risk was recorded for lung cancer. The high SMR for lung cancer in female subjects is especially striking. Because the numbers were low for the other cancer sites, these were combined in one group to calculate the SMR. No significant increase in SMR was found for this group

  7. Source Apportionment of Background PAHs in the Peace-Athabasca Delta (Alberta, Canada) Using Molecular Level Radiocarbon Analysis.

    Science.gov (United States)

    Jautzy, Josué J; Ahad, Jason M E; Hall, Roland I; Wiklund, Johan A; Wolfe, Brent B; Gobeil, Charles; Savard, Martine M

    2015-08-04

    The downstream accumulation of polycyclic aromatic hydrocarbons (PAHs) in the Peace-Athabasca Delta (PAD), an ecologically important landscape, is a key issue of concern given the rapid development of the oil sands industry in Northern Alberta, Canada. In addition to PAHs derived from industrial activity (i.e., oil sands mining) within the Athabasca watershed, however, forest fires and erosion of fossil fuel deposits within both the Athabasca and Peace watersheds are two potentially important natural sources of PAHs delivered to the PAD. Consequently, evaluating the environmental impact of mining activities requires a quantitative understanding of natural, background PAHs. Here, we utilize molecular-level natural-abundance radiocarbon measurements on an amalgamated sediment record from a Peace River flood-susceptible oxbow lake in the northern Peace sector of the PAD to quantitatively discriminate sources of naturally occurring alkylated PAHs (fossil and modern biomass). A radiocarbon mass balance quantified a predominantly natural petrogenic source (93% petrogenic, 7% forest fire) for alkylated PAHs during the past ∼50 years. Additionally, a significant petrogenic component determined for retene, a compound usually considered a biomarker for softwood combustion, suggests that its use as a unique forest fire indicator may not be suitable in PAD sediments receiving Peace watershed-derived fluvial inputs.

  8. Technetium Chemistry in High-Level Waste

    International Nuclear Information System (INIS)

    Hess, Nancy J.

    2006-01-01

    Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry

  9. Processing vessel for high level radioactive wastes

    International Nuclear Information System (INIS)

    Maekawa, Hiromichi

    1998-01-01

    Upon transferring an overpack having canisters containing high level radioactive wastes sealed therein and burying it into an underground processing hole, an outer shell vessel comprising a steel plate to be fit and contained in the processing hole is formed. A bury-back layer made of dug earth and sand which had been discharged upon forming the processing hole is formed on the inner circumferential wall of the outer shell vessel. A buffer layer having a predetermined thickness is formed on the inner side of the bury-back layer, and the overpack is contained in the hollow portion surrounded by the layer. The opened upper portion of the hollow portion is covered with the buffer layer and the bury-back layer. Since the processing vessel having a shielding performance previously formed on the ground, the state of packing can be observed. In addition, since an operator can directly operates upon transportation and burying of the high level radioactive wastes, remote control is no more necessary. (T.M.)

  10. Tracking at High Level Trigger in CMS

    CERN Document Server

    Tosi, Mia

    2016-01-01

    The trigger systems of the LHC detectors play a crucial role in determining the physics capabili- ties of the experiments. A reduction of several orders of magnitude of the event rate is needed to reach values compatible with detector readout, offline storage and analysis capability. The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger (L1T), implemented on custom-designed electronics, and the High Level Trigger (HLT), a stream- lined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a trade-off between the complexity of the algorithms, the sustainable out- put rate, and the selection efficiency. With the computing power available during the 2012 data taking the maximum reconstruction time at HLT was about 200 ms per event, at the nominal L1T rate of 100 kHz. Track reconstruction algorithms are widely used in the HLT, for the reconstruction of the physics objects as well as in the identification of b-jets and ...

  11. CMS High Level Trigger Timing Measurements

    International Nuclear Information System (INIS)

    Richardson, Clint

    2015-01-01

    The two-level trigger system employed by CMS consists of the Level 1 (L1) Trigger, which is implemented using custom-built electronics, and the High Level Trigger (HLT), a farm of commercial CPUs running a streamlined version of the offline CMS reconstruction software. The operational L1 output rate of 100 kHz, together with the number of CPUs in the HLT farm, imposes a fundamental constraint on the amount of time available for the HLT to process events. Exceeding this limit impacts the experiment's ability to collect data efficiently. Hence, there is a critical need to characterize the performance of the HLT farm as well as the algorithms run prior to start up in order to ensure optimal data taking. Additional complications arise from the fact that the HLT farm consists of multiple generations of hardware and there can be subtleties in machine performance. We present our methods of measuring the timing performance of the CMS HLT, including the challenges of making such measurements. Results for the performance of various Intel Xeon architectures from 2009-2014 and different data taking scenarios are also presented. (paper)

  12. Effect of high gamma background on neutron sensitivity of fission detectors

    International Nuclear Information System (INIS)

    Balagi, V.; Prasad, K.R.; Kataria, S.K.

    2004-01-01

    Tests were performed on two parallel plate and two cylindrical fission detectors in pulse and dc mode. The effect of gamma background on neutron sensitivity was studied in thermal neutron flux from 30 nv to 60 nv over which gamma field intensity ranging from 230 kR/h to 3.7 MR/h was superposed. In the case of one of the parallel plate detectors the fall in neutron sensitivity was observed to be 3.7% at 1 MR/h and negligible below 1 MR/h. In the case of one of the cylindrical counters the fall in neutron sensitivity was negligible below 500 kR/h and 37% at 1 MR/h. The data was used to derive the design parameters for a wide range fission detector to be procured for PFBR instrumentation for operation at 600 degC and gamma background of 1 MR/h. (author)

  13. The Influence of Geography and Geology on Seismic Background Noise Levels Across the United States as Revealed by the Transportable Array

    Science.gov (United States)

    Anthony, R. E.; Ringler, A. T.; Holland, A. A.; Wilson, D. C.

    2017-12-01

    The EarthScope USArray Transportable Array (TA) has now covered the US with 3-component broadband seismometers at approximately 70 km station spacing and deployment durations of approximately 2 years. This unprecedented coverage, combined with high-quality and near homogenous installation techniques, offers a novel dataset in which to characterize spatially varying levels of background seismic noise across the United States. We present background noise maps in period bands of interest to earthquake and imaging seismology across the US (lower 48 states and Alaska). Early results from the contiguous 48 states demonstrate that ambient noise levels within the body wave period band (1-5 s) vary by > 20 dB (rel. 1 (m/s2)2/Hz) with the highest noise levels occurring at stations located within sedimentary basins and lowest within the mountain ranges of the Western US. Additionally, stations around the Great Lakes observe heightened noise levels in this band beyond the aforementioned basin amplification. We attribute this observation to local swell activity in the Great Lakes generating short-period microseism signals. This suggests that lake-generated microseisms may be a significant source of noise for Alaskan deployments situated in close proximity to lakes to facilitate float plane access. We further investigate how basin amplification and short-period lake microseism signals may noticeably impact detection and signal-to-noise of teleseismic body wave signals during certain time periods. At longer-periods (> 20 s), we generally observe larger noise levels on the horizontal components of stations situated in basins or on soft sediment, likely caused by locally induced tilt of the sensor. We will present similar analysis from the initial Alaska TA dataset to quantitatively assess how utilization of posthole sensors affects signal-to-noise for the long-period horizontal wavefield.

  14. Association Between Educational Level and Risk of Cancer in HIV-infected Individuals and the Background Population: Population-based Cohort Study 1995-2011.

    Science.gov (United States)

    Legarth, Rebecca; Omland, Lars H; Dalton, Susanne O; Kronborg, Gitte; Larsen, Carsten S; Pedersen, Court; Pedersen, Gitte; Gerstoft, Jan; Obel, Niels

    2015-11-15

    Human immunodeficiency virus (HIV)-infected individuals have increased risk of cancer. To our knowledge, no previous study has examined the impact of socioeconomic position on risk and prognosis of cancer in HIV infection. Population-based cohort-study, including HIV-infected individuals diagnosed (without intravenous drug abuse or hepatitis C infection) (n = 3205), and a background population cohort matched by age, gender, and country of birth (n = 22 435) were analyzed. Educational level (low or high) and cancer events were identified in Danish national registers. Cumulative incidences, incidence rate ratios (IRRs), and survival using Kaplan-Meier methods were estimated. Low educational level was associated with increased risk of cancer among HIV-infected individuals compared to population controls: all (adjusted-IRRs: 1.4 [95% confidence interval {CI}, 1.1-1.7] vs 1.1 [95% CI, .9-1.2]), tobacco- and alcohol-related (2.1 [95% CI, 1.3-3.4] vs 1.3 [95% CI, 1.1-1.6]), and other (1.7 [95% CI, 1.1-2.8] vs 0.9 [95% CI, .7-1.0]). Educational level was not associated with infection-related or ill-defined cancers. One-year-survival was not associated with educational level, but HIV-infected individuals with low educational level had lower 5-year-survival following infection-related and ill-defined cancers. Education is associated with risk and prognosis of some cancers in HIV infection, and diverges from what is observed in the background population. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Effect of high hydrostatic pressure processing on the background microbial loads and quality of cantaloupe puree.

    Science.gov (United States)

    Mukhopadhyay, Sudarsan; Sokorai, Kimberly; Ukuku, Dike; Fan, Xuetong; Juneja, Vijay

    2017-01-01

    The objective of this study was to investigate and evaluate the effects of high hydrostatic pressure (HHP) applied to cantaloupe puree (CP) on microbial loads and product quality during storage for 10days at 4°C. Freshly prepared, double sealed and double bagged CP (ca. 5g) was pressure treated at 300, 400 and 500MPa at 8°C and 15°C for 5min. Microflora populations, soluble solid content, pH, color, antioxidant activity, appearance and aroma were measured at 1, 6, and 10d of storage. Results showed that high pressure treatment of 300MPa (8°C and 15°C) resulted in reduction of total aerobic plate count from 3.3 to 1.8logCFU/g. The treatment reduced the populations of native aerobic plate count to non-detectable levels (detection limit 1logCFU/g) at 400MPa and 500MPa pressures at 15°C. Pressure treatment completely inactivated mold and yeast in puree below the limits of detection at day 1 and no regrowth was observed during 10days of storage at 4°C while mold and yeast in untreated puree survived during the storage. High pressure treatment did not show any adverse impact on physical properties as soluble solid content (SSC, 11.2°Brix) and acidity (pH, 6.9). The instrumental color parameters (L*, a*, b*) were affected due to HHP treatment creating a slightly lighter product, compared to control, as indicated by higher L.* and lower a* values. However the change was not detected by the sensory panel while evaluating appearance scores. Pressure treatment did not affect the antioxidant capacity of puree product compared to control. Visual appearance and sniffing aroma test by panel revealed no adverse changes in the sensory parameters as a result of HHP treatment. HHP method described in this study appears to be a promising way to inactivate spoilage microorganisms in the cantaloupe puree and maintain quality. This study provides a viable option for preservation and marketing this product. Published by Elsevier Ltd.

  16. Epidemiological and radio-biological studies in high background radiation areas of Kerala coast: implications in radiation protection science and human health

    International Nuclear Information System (INIS)

    Das, Birajalaxmi

    2018-01-01

    Till date, Linear No Threshold hypothesis (LNT) is well accepted in radiation protection science in spite of its limitations. However, dose response studies using multiple biological end points from high-background radiation areas have challenged the linearity. Radio-biological and epidemiological studies from high level natural radiation areas of Kerala coast showed non-linearity as well as efficient repair of DNA damage in HLNRA indicating that dose limits for public exposure needs to be revisited which may have implications in radiation protection science, human health and low dose radiation biology. However, further studies using high throughput approach is required to identify chronic radiation signatures in human population exposed to elevated level of natural background radiation

  17. Evaluation of thyroid function in female subjects living in the high natural background radiation area of Karunagappally, Kerala

    International Nuclear Information System (INIS)

    Sreekumar, A.; Nair, Raghu Ram K.; Jayalakshmi, P.; Sebastian, P.; Akiba, S.

    2010-01-01

    Radiation exposure has been reported to cause non cancer thyroid abnormalities like diffuse goiter and thyroid nodules. The present study was undertaken to see if there are any morphological and functional changes taking place in the thyroid due to chronic low level radiation exposure. 257 female subjects living in the four high background radiation panchayats of Chavara, Neendakara, Alappad and Panmana were selected for the study after getting informed consent. 5 ml of blood was drawn from these subjects for assessing thyroid function. The subjects were all staying in the same area since their birth and had not moved out for more than one year at a stretch. The average age of the subjects was 40.5y with a range of 17-66y. The cumulative dose had a mean of 226.3 mGy and a range of 20.6-937.8 mGy. 95 subjects from the low background area of Oachira and Thevalakkara were selected as controls in the age group of 18-63y with a mean age of 47.1y. The mean cumulative dose of this group was 35.9 mGy with a minimum of 5.3 mGy and a maximum of 106.8 mGy. 5 ml blood was collected from these subjects for thyroid function studies. All the subjects underwent ultrasound examination of the thyroid using a 10 MHz frequency linear probe. The following parameters were studied to assess thyroid function: Free T4, TSH, Antithyroglobulin antibody (ATG), Parathyroid hormone. Ultrasound images showed the following common features: Normal - 171, Suggestive of Thyroiditis - 106, Multinodular Goitre - 63, Diffuse Goitre - 5, Solitary Nodule - 31. 73 subjects had elevated TSH and 190 subjects had raised ATG. A significant numbers of subjects had features of thyroiditis. A comparative evaluation with control subjects will be done to assess its significance with reference to cumulative dose

  18. CAMAC and high-level-languages

    International Nuclear Information System (INIS)

    Degenhardt, K.H.

    1976-05-01

    A proposal for easy programming of CAMAC systems with high-level-languages (FORTRAN, RTL/2, etc.) and interpreters (BASIC, MUMTI, etc.) using a few subroutines and a LAM driver is presented. The subroutines and the LAM driver are implemented for PDP11/RSX-11M and for the CAMAC controllers DEC CA11A (branch controller), BORER type 1533A (single crate controller) and DEC CA11F (single crate controller). Mixed parallel/serial CAMAC systems employing KINETIC SYSTEMS serial driver mod. 3992 and serial crate controllers mod. 3950 are implemented for all mentioned parallel controllers, too. DMA transfers from or to CAMAC modules using non-processor-request controllers (BORER type 1542, DEC CA11FN) are available. (orig.) [de

  19. National high-level waste systems analysis

    International Nuclear Information System (INIS)

    Kristofferson, K.; O'Holleran, T.P.

    1996-01-01

    Previously, no mechanism existed that provided a systematic, interrelated view or national perspective of all high-level waste treatment and storage systems that the US Department of Energy manages. The impacts of budgetary constraints and repository availability on storage and treatment must be assessed against existing and pending negotiated milestones for their impact on the overall HLW system. This assessment can give DOE a complex-wide view of the availability of waste treatment and help project the time required to prepare HLW for disposal. Facilities, throughputs, schedules, and milestones were modeled to ascertain the treatment and storage systems resource requirements at the Hanford Site, Savannah River Site, Idaho National Engineering Laboratory, and West Valley Demonstration Project. The impacts of various treatment system availabilities on schedule and throughput were compared to repository readiness to determine the prudent application of resources. To assess the various impacts, the model was exercised against a number of plausible scenarios as discussed in this paper

  20. International high-level radioactive waste repositories

    International Nuclear Information System (INIS)

    Lin, W.

    1996-01-01

    Although nuclear technologies benefit everyone, the associated nuclear wastes are a widespread and rapidly growing problem. Nuclear power plants are in operation in 25 countries, and are under construction in others. Developing countries are hungry for electricity to promote economic growth; industrialized countries are eager to export nuclear technologies and equipment. These two ingredients, combined with the rapid shrinkage of worldwide fossil fuel reserves, will increase the utilization of nuclear power. All countries utilizing nuclear power produce at least a few tens of tons of spent fuel per year. That spent fuel (and reprocessing products, if any) constitutes high-level nuclear waste. Toxicity, long half-life, and immunity to chemical degradation make such waste an almost permanent threat to human beings. This report discusses the advantages of utilizing repositories for disposal of nuclear wastes

  1. Natural radioactivity and associated radiation characteristic of the new high background radiation area of lambwe east southern Kenya

    International Nuclear Information System (INIS)

    Achola, S.O.; Patel, J.P.; Angeyo, H.K.; Mustapha, A.O.

    2010-01-01

    Rocks and soils from a number of areas underlined by carbonatite rocks in Kenya have been associated with high levels of natural background radioactivity. People in such high background radiation areas (HBRA), are exposed to abnormally high annual absorbed dose (that have health implications) than the global normal 1 mSvyr-1. In this paper, results of field background radiation measurements, activity concentrations of primordial radionuclides in (mainly carbonatite rock and soil) matrices, and estimated annual external effective dose rates are presented for South and North Ruri hills in Lambwe East location of Suba District, which lies roughly between latitudes 0°30'S and 1°00'S, bounded on the east by longitude 34°30'E and on the west by the shores of Lake Victoria 16 and Winnam Gulf. Altitudes in the region range from about 1000 m on the shores of Lake Victoria to above 1800 m on top of the Ruri hills. The main geological features are carbonatite formations. Twenty one samples were analyzed using high-purity germanium (HPGe) gamma-ray spectrometer. The activity concentrations ranged 14.18 - 6559.99 Bqkg-1 (average: 1396.85 Bqkg-1) for Th-232; 2.73 - 499.24 Bqkg-1 (average: 178.69 Bqkg-1) for U-238; and 56.67 - 1454.73 Bqkg-1 (average: 508.67 Bqkg-1) for K-40. The variability in Th distribution could be due to another contributing factor apart from carbonatite: Homa hills geothermal field fluids might be responsible for delivery of Th to surface rocks; some hot spots have travertine deposits. Measured absorbed dose rates in air outdoors range 700 - 6000.00 nGyh-1 (mean: 2325.84 nGy h-1); assuming 0.4 occupancy factor, these values correspond to individual annual effective dose rates of 1.717 - 14.717 mSvyr-1 (mean: 5.705 mSv yr-1). Measured absorbed dose rates are higher than calculated values since they include the contribution of cosmic rays. The natural radioactivity is fractionated with higher levels in the soils than carbonatite rocks

  2. High-level waste processing and disposal

    International Nuclear Information System (INIS)

    Crandall, J.L.; Krause, H.; Sombret, C.; Uematsu, K.

    1984-11-01

    Without reprocessing, spent LWR fuel itself is generally considered an acceptable waste form. With reprocessing, borosilicate glass canisters, have now gained general acceptance for waste immobilization. The current first choice for disposal is emplacement in an engineered structure in a mined cavern at a depth of 500-1000 meters. A variety of rock types are being investigated including basalt, clay, granite, salt, shale, and volcanic tuff. This paper gives specific coverage to the national high level waste disposal plans for France, the Federal Republic of Germany, Japan and the United States. The French nuclear program assumes prompt reprocessing of its spent fuels, and France has already constructed the AVM. Two larger borosilicate glass plants are planned for a new French reprocessing plant at La Hague. France plans to hold the glass canisters in near-surface storage for a forty to sixty year cooling period and then to place them into a mined repository. The FRG and Japan also plan reprocessing for their LWR fuels. Both are currently having some fuel reprocessed by France, but both are also planning reprocessing plants which will include waste vitrification facilities. West Germany is now constructing the PAMELA Plant at Mol, Belgium to vitrify high level reprocessing wastes at the shutdown Eurochemic Plant. Japan is now operating a vitrification mockup test facility and plans a pilot plant facility at the Tokai reprocessing plant by 1990. Both countries have active geologic repository programs. The United State program assumes little LWR fuel reprocessing and is thus primarily aimed at direct disposal of spent fuel into mined repositories. However, the US have two borosilicate glass plants under construction to vitrify existing reprocessing wastes

  3. Transcriptome Analyses of Mosaic (MSC Mitochondrial Mutants of Cucumber in a Highly Inbred Nuclear Background

    Directory of Open Access Journals (Sweden)

    Tomasz L. Mróz

    2018-03-01

    Full Text Available Cucumber (Cucumis sativus L. has a large, paternally transmitted mitochondrial genome. Cucumber plants regenerated from cell cultures occasionally show paternally transmitted mosaic (MSC phenotypes, characterized by slower growth, chlorotic patterns on the leaves and fruit, lower fertility, and rearrangements in their mitochondrial DNAs (mtDNAs. MSC lines 3, 12, and 16 originated from different cell cultures all established using the highly inbred, wild-type line B. These MSC lines possess different rearrangements and under-represented regions in their mtDNAs. We completed RNA-seq on normalized and non-normalized cDNA libraries from MSC3, MSC12, and MSC16 to study their nuclear gene-expression profiles relative to inbred B. Results from both libraries indicated that gene expression in MSC12 and MSC16 were more similar to each other than MSC3. Forty-one differentially expressed genes (DEGs were upregulated and one downregulated in the MSC lines relative to B. Gene functional classifications revealed that more than half of these DEGs are associated with stress-response pathways. Consistent with this observation, we detected elevated levels of hydrogen peroxide throughout leaf tissue in all MSC lines compared to wild-type line B. These results demonstrate that independently produced MSC lines with different mitochondrial polymorphisms show unique and shared nuclear responses. This study revealed genes associated with stress response that could become selection targets to develop cucumber cultivars with increased stress tolerance, and further support of cucumber as a model plant to study nuclear-mitochondrial interactions.

  4. Epidemiology of high-level parvovirus B19 viraemia among Dutch blood donors, 2003-2009

    NARCIS (Netherlands)

    Kooistra, K.; Mesman, H. J.; de Waal, M.; Koppelman, M. H. G. M.; Zaaijer, H. L.

    2011-01-01

    Background and Objectives Plasma derivatives and blood components with low levels of parvovirus B19 (B19) seem not infectious, but recently infected, highly viraemic donors may transmit B19. We studied the incidence of high-level B19 viraemia (B19 DNA > 106 IU/ml) in 6 center dot 5 million Dutch

  5. Characterization of gaseous detectors at the CERN Gamma Irradiation Facility: GEM performance in presence of high background radiation

    CERN Document Server

    AUTHOR|(CDS)2097588

    Muon detection is an efficient tool to recognize interesting physics events over the high background rate expected at the Large Hadron Collider (LHC) at CERN. The muon systems of the LHC experiments are based on gaseous ionization detectors. In view of the High-Luminosity LHC (HL-LHC) upgrade program, the increasing of background radiation could affect the gaseous detector performance, especially decreasing the efficiency and shortening the lifetime through ageing processes. The effects of charge multiplication, materials and gas composition on the ageing of gaseous detectors have been studied for decades, but the future upgrade of LHC requires additional studies on this topic. At the CERN Gamma Irradiation Facility (GIF++), a radioactive source of cesium-137 with an activity of 14 TBq is used to reproduce reasonably well the expected background radiation at HL-LHC. A muon beam has been made available to study detector performance. The characterization of the beam trigger will be discussed in the present w...

  6. Handbook of high-level radioactive waste transportation

    International Nuclear Information System (INIS)

    Sattler, L.R.

    1992-10-01

    The High-Level Radioactive Waste Transportation Handbook serves as a reference to which state officials and members of the general public may turn for information on radioactive waste transportation and on the federal government's system for transporting this waste under the Civilian Radioactive Waste Management Program. The Handbook condenses and updates information contained in the Midwestern High-Level Radioactive Waste Transportation Primer. It is intended primarily to assist legislators who, in the future, may be called upon to enact legislation pertaining to the transportation of radioactive waste through their jurisdictions. The Handbook is divided into two sections. The first section places the federal government's program for transporting radioactive waste in context. It provides background information on nuclear waste production in the United States and traces the emergence of federal policy for disposing of radioactive waste. The second section covers the history of radioactive waste transportation; summarizes major pieces of legislation pertaining to the transportation of radioactive waste; and provides an overview of the radioactive waste transportation program developed by the US Department of Energy (DOE). To supplement this information, a summary of pertinent federal and state legislation and a glossary of terms are included as appendices, as is a list of publications produced by the Midwestern Office of The Council of State Governments (CSG-MW) as part of the Midwestern High-Level Radioactive Waste Transportation Project

  7. Non-cancer disease mortality among inhabitants in the high background radiation area of Yangjiang, China (1979-1998)

    International Nuclear Information System (INIS)

    Sun Quanfu; Akiba, Suminori; Zou Jianming

    2008-01-01

    Much is still unknown about the health effects of low-level radiation on human health, particularly on the risk of non-cancer diseases. A review by Radiation Effects Research Foundation (RERF) scientists has concluded that the association of atomic-bomb radiation and cardiovascular disease (CVD) is almost certain since the relationship was shown by incidence and prevalence studies of various endpoints of atherosclerosis. In addition to the studies of atomic bomb survivors, the association of CVD with radiation exposure was observed in several other studies, including the follow-up study of patients treated for Hodgkin lymphoma, ankylosing spondilitis, peptic ulcer and scoliosis as well as nuclear workers. The inhabitants in the high background radiation area (HBRA) of Yangjiang, Guangdong Province, China receive the external radiation doses of 1.33 mSv in excess every year, mainly from exposure to terrestrial gamma ray, when compared to the residents in the neighboring control area (CA). Our most recent analysis of cancer mortality among residents in the HBRA and the CA showed no evident difference between the two areas. It should be of note that the crude cancer mortality rate in the study population was 60/100,000 person-years, which is much lower than cancer mortality in developed countries. On the other hand, non cancer deaths accounted for 90% of all deaths. In this report, we present the results of mortality analysis for non-cancer diseases during the period 1979-1998. (author)

  8. High-level radioactive waste management

    International Nuclear Information System (INIS)

    Schneider, K.J.; Liikala, R.C.

    1974-01-01

    High-level radioactive waste in the U.S. will be converted to an encapsulated solid and shipped to a Federal repository for retrievable storage for extended periods. Meanwhile the development of concepts for ultimate disposal of the waste which the Federal Government would manage is being actively pursued. A number of promising concepts have been proposed, for which there is high confidence that one or more will be suitable for long-term, ultimate disposal. Initial evaluations of technical (or theoretical) feasibility for the various waste disposal concepts show that in the broad category, (i.e., geologic, seabed, ice sheet, extraterrestrial, and transmutation) all meet the criteria for judging feasibility, though a few alternatives within these categories do not. Preliminary cost estimates show that, although many millions of dollars may be required, the cost for even the most exotic concepts is small relative to the total cost of electric power generation. For example, the cost estimates for terrestrial disposal concepts are less than 1 percent of the total generating costs. The cost for actinide transmutation is estimated at around 1 percent of generation costs, while actinide element disposal in space is less than 5 percent of generating costs. Thus neither technical feasibility nor cost seems to be a no-go factor in selecting a waste management system. The seabed, ice sheet, and space disposal concepts face international policy constraints. The information being developed currently in safety, environmental concern, and public response will be important factors in determining which concepts appear most promising for further development

  9. Evaluation of lectin pathway activity and mannan-binding lectin levels in the course of pregnancy complicated by diabetes type 1, based on the genetic background.

    Science.gov (United States)

    Pertyńska Marczewska, Magdalena; Cedzyński, Maciej; Swierzko, Anna; Szala, Agnieszka; Sobczak, Małgorzata; Cypryk, Katarzyna; Wilczyński, Jan

    2009-01-01

    There are numerous indications that either mannan-binding lectin (MBL) deficiency or its excessive activity are associated with adverse pregnancy outcomes. High MBL concentrations and corresponding MBL2 genotypes were shown to be associated with microvascular complications in type 1 diabetes. The aim of this study was to evaluate levels of MBL and MBL-dependent activity of the lectin pathway (LP) of complement in the course of pregnancy in diabetic mothers, based on genetic background. These parameters were determined in samples from healthy non-pregnant (control), diabetic non-pregnant, healthy pregnant, and pregnant diabetic women. No significant differences in median MBL levels or LP activities were found in any study group compared to the control. However, statistically significant differences in MBL levels were noted during pregnancy between the 1st and 3rd trimesters in both healthy controls and pregnant diabetics. With regard to LP values, similar trends were evident, but statistically significant results were obtained only in the healthy pregnant group. When data analysis was confined to patients carrying the A/A (wild-type) MBL2 genotype, an increase in MBL level during pregnancy (in both healthy and diabetic pregnant women) was still observed. Similarly, LP activity increased during both healthy and diabetic pregnancies, significantly so for the former. Diabetes, an autoimmune disease, is a serious complication of pregnancy. Therefore, determination of MBL status might be beneficial in identifying type 1 diabetic patients who are at increased risk of developing both vascular complications and poor pregnancy outcomes.

  10. Resolution and Efficiency of the ATLAS Muon Drift-Tube Chambers at High Background Rates

    CERN Document Server

    Deile, M.; Horvat, S.; Kortner, O.; Kroha, H.; Manz, A.; Mohrdieck-Mock, S.; Rauscher, F.; Richter, Robert; Staude, A.; Stiller, W.

    2016-01-01

    The resolution and efficiency of a precision drift-tube chamber for the ATLAS muon spectrometer with final read-out electronics was tested at the Gamma Irradiation Facility at CERN in a 100 GeV muon beam and at photon irradiation rates of up to 990 Hz/square cm which corresponds to twice the highest background rate expected in ATLAS. A silicon strip detector telescope was used as external reference in the beam. The pulse-height measurement of the read-out electronics was used to perform time-slewing corrections which lead to an improvement of the average drift-tube resolution from 104 microns to 82 microns without irradiation and from 128 microns to 108 microns at the maximum expected rate. The measured drift-tube efficiency agrees with the expectation from the dead time of the read-out electronics up to the maximum expected rate.

  11. A measurement of the cosmic microwave background from the high Chilean Andes

    Science.gov (United States)

    Miller, Amber Dawn

    A measurement of the angular spectrum of the Cosmic Microwave Background (CMB) between l = 50 and l = 400 is described. Data were obtained using HEMT radiometers at 30 and 40 GHz with angular resolutions of ≈1 deg and ≈0.7 deg respectively and with SIS based receivers at 144 GHz with angular resolution of ≈0.2 deg. Observations were made from Cerro Toco in the Chilean altiplano at an altitude of 17,000 feet in the Northern Chilean Andes. We find that the angular spectrum rises from l = 50 to a peak at l ≈ 200 and falls off at higher angular scales. A peak in the angular spectrum with amplitude, deltaTl ≈ 85muK is thus located for the first time with a single instrument at l ≈ 200. In addition, we find that the detected anisotropy has the spectrum of the CMB. Cosmological implications of this result are discussed.

  12. Vitrification of high-level liquid wastes

    International Nuclear Information System (INIS)

    Varani, J.L.; Petraitis, E.J.; Vazquez, Antonio.

    1987-01-01

    High-level radioactive liquid wastes produced in the fuel elements reprocessing require, for their disposal, a preliminary treatment by which, through a series of engineering barriers, the dispersion into the biosphere is delayed by 10 000 years. Four groups of compounds are distinguished among a great variety of final products and methods of elaboration. From these, the borosilicate glasses were chosen. Vitrification experiences were made at a laboratory scale with simulated radioactive wastes, employing different compositions of borosilicate glass. The installations are described. A series of tests were carried out on four basic formulae using always the same methodology, consisting of a dry mixture of the vitreous matrix's products and a dry simulated mixture. Several quality tests of the glasses were made 1: Behaviour in leaching following the DIN 12 111 standard; 2: Mechanical resistance; parameters related with the facility of the different glasses for increasing their surface were studied; 3: Degree of devitrification: it is shown that devitrification turns the glasses containing radioactive wastes easily leachable. From all the glasses tested, the composition SiO 2 , Al 2 O 3 , B 2 O 3 , Na 2 O, CaO shows the best retention characteristics. (M.E.L.) [es

  13. Ocean disposal of high level radioactive waste

    International Nuclear Information System (INIS)

    1983-01-01

    This study confirms, subject to limitations of current knowledge, the engineering feasibility of free fall penetrators for High Level Radioactive Waste disposal in deep ocean seabed sediments. Restricted sediment property information is presently the principal bar to an unqualified statement of feasibility. A 10m minimum embedment and a 500 year engineered barrier waste containment life are identified as appropriate basic penetrator design criteria at this stage. A range of designs are considered in which the length, weight and cross section of the penetrator are varied. Penetrators from 3m to 20m long and 2t to 100t in weight constructed of material types and thicknesses to give a 500 year containment life are evaluated. The report concludes that the greatest degree of confidence is associated with performance predictions for 75 to 200 mm thick soft iron and welded joints. A range of lengths and capacities from a 3m long single waste canister penetrator to a 20m long 12 canister design are identified as meriting further study. Estimated embedment depths for this range of penetrator designs lie between 12m and 90m. Alternative manufacture, transport and launch operations are assessed and recommendations are made. (author)

  14. High-level nuclear waste disposal

    International Nuclear Information System (INIS)

    Burkholder, H.C.

    1985-01-01

    The meeting was timely because many countries had begun their site selection processes and their engineering designs were becoming well-defined. The technology of nuclear waste disposal was maturing, and the institutional issues arising from the implementation of that technology were being confronted. Accordingly, the program was structured to consider both the technical and institutional aspects of the subject. The meeting started with a review of the status of the disposal programs in eight countries and three international nuclear waste management organizations. These invited presentations allowed listeners to understand the similarities and differences among the various national approaches to solving this very international problem. Then seven invited presentations describing nuclear waste disposal from different perspectives were made. These included: legal and judicial, electric utility, state governor, ethical, and technical perspectives. These invited presentations uncovered several issues that may need to be resolved before high-level nuclear wastes can be emplaced in a geologic repository in the United States. Finally, there were sixty-six contributed technical presentations organized in ten sessions around six general topics: site characterization and selection, repository design and in-situ testing, package design and testing, disposal system performance, disposal and storage system cost, and disposal in the overall waste management system context. These contributed presentations provided listeners with the results of recent applied RandD in each of the subject areas

  15. Decontamination of high-level waste canisters

    International Nuclear Information System (INIS)

    Nesbitt, J.F.; Slate, S.C.; Fetrow, L.K.

    1980-12-01

    This report presents evaluations of several methods for the in-process decontamination of metallic canisters containing any one of a number of solidified high-level waste (HLW) forms. The use of steam-water, steam, abrasive blasting, electropolishing, liquid honing, vibratory finishing and soaking have been tested or evaluated as potential techniques to decontaminate the outer surfaces of HLW canisters. Either these techniques have been tested or available literature has been examined to assess their applicability to the decontamination of HLW canisters. Electropolishing has been found to be the most thorough method to remove radionuclides and other foreign material that may be deposited on or in the outer surface of a canister during any of the HLW processes. Steam or steam-water spraying techniques may be adequate for some applications but fail to remove all contaminated forms that could be present in some of the HLW processes. Liquid honing and abrasive blasting remove contamination and foreign material very quickly and effectively from small areas and components although these blasting techniques tend to disperse the material removed from the cleaned surfaces. Vibratory finishing is very capable of removing the bulk of contamination and foreign matter from a variety of materials. However, special vibratory finishing equipment would have to be designed and adapted for a remote process. Soaking techniques take long periods of time and may not remove all of the smearable contamination. If soaking involves pickling baths that use corrosive agents, these agents may cause erosion of grain boundaries that results in rough surfaces

  16. High-energy neutrino background: Limitations on models of deuterium production

    International Nuclear Information System (INIS)

    Eichler, D.

    1979-01-01

    It is pointed out that Epstein's model for deuterium production via high-energy spallation reactions produces high-energy neutrinos in sufficient quantity to stand out above those that are produced by cosmic-ray interactions in the Earth's atmosphere. That the Reines experiment detected neutrinos of atmospheric origin without detecting any cosmic component restricts deuterium production by spallation reactions to very high redshifts (z> or approx. =300). Improved neutrino experiments may be able to push these limits back to recombination

  17. Analysis of data (1987-1995) from investigation of cancer mortality in high background radiation area of Yangjiang, China

    International Nuclear Information System (INIS)

    Tao Zufan; Akiba, S.; Zha Yongru

    1999-01-01

    Objective: This investigation is a special project of High Background Radiation Research Group. The objective of the cancer mortality study in the high background radiation area (HBRA) of Yangjiang, China, which was started in 1972, was to estimate cancer risk associated with the low level radiation exposure of average annual effective dose of 6.4 mSv in HBRA. Since 1991, the study has been conducted collaboratively by Chinese and Japanese scientists with the purpose of accumulating further person years (Pyr) of observation for improving the statistical precision and seeing the reproducibility of the previous results. Methods: The cancer mortality data of 1987-1995 covered in the current cooperative study were collected by a retrospective and/or prospective survey from a fixed cohort. The mortality investigation on the spot consisted of two steps, i.e. the follow-up of members in the cohort and the ascertainment of the death causes. Based on the hamlet-specific average annual external dose, the members of the cohort in HBRA were classified into three groups: high, medial and low dose groups. Risk comparisons between each of the three dose groups with the control group from control area (CA) were conducted by means of relative risk (RR). The RR and the excess relative risk coefficient (ERR per sievert) and their y 95% confidence interval (CI) were estimated using AMFIT program in Epicure. Results: During the period 1987-1995, there were 5161 total deaths and 557 cancer deaths among 926238 Pyr at risk in the cohort of 106517 subjects. The RR (95% CI) adjusted for sex and age group for all cancers of whole HBRA was 0.96 (0.80-1.15). As for the site-specific cancer of whole HBRA, the RRs for leukemia, cancers of nasopharynx, esophagus and intestine were larger than one, while the RRs for cancers of stomach, liver, lungs, female breast, thyroid and lymphoma were less than one. However, all of them were not statistically different from one (P>0.05 for all). The

  18. DEFENSE HIGH LEVEL WASTE GLASS DEGRADATION

    International Nuclear Information System (INIS)

    Ebert, W.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the analyses that were done to develop models for radionuclide release from high-level waste (HLW) glass dissolution that can be integrated into performance assessment (PA) calculations conducted to support site recommendation and license application for the Yucca Mountain site. This report was developed in accordance with the ''Technical Work Plan for Waste Form Degradation Process Model Report for SR'' (CRWMS M andO 2000a). It specifically addresses the item, ''Defense High Level Waste Glass Degradation'', of the product technical work plan. The AP-3.15Q Attachment 1 screening criteria determines the importance for its intended use of the HLW glass model derived herein to be in the category ''Other Factors for the Postclosure Safety Case-Waste Form Performance'', and thus indicates that this factor does not contribute significantly to the postclosure safety strategy. Because the release of radionuclides from the glass will depend on the prior dissolution of the glass, the dissolution rate of the glass imposes an upper bound on the radionuclide release rate. The approach taken to provide a bound for the radionuclide release is to develop models that can be used to calculate the dissolution rate of waste glass when contacted by water in the disposal site. The release rate of a particular radionuclide can then be calculated by multiplying the glass dissolution rate by the mass fraction of that radionuclide in the glass and by the surface area of glass contacted by water. The scope includes consideration of the three modes by which water may contact waste glass in the disposal system: contact by humid air, dripping water, and immersion. The models for glass dissolution under these contact modes are all based on the rate expression for aqueous dissolution of borosilicate glasses. The mechanism and rate expression for aqueous dissolution are adequately understood; the analyses in this AMR were conducted to

  19. Low Noise Infrasonic Sensor System with High Reduction of Natural Background Noise

    National Research Council Canada - National Science Library

    Kern, F; Africk, S; Cataldi, P; Chaves, R

    2006-01-01

    ...) coaxial cables, theoretically of arbitrary length, specially terminated and connected to state of the art, ultra high input impedance quiet amplifiers, tailored to the unique characteristics of the sensor outputs...

  20. X-ray detection with Micromegas with background levels below 10$^{-6}$ keV$^{-1}$cm$^{-2}$s$^{-1}$

    CERN Document Server

    Aune, S; Calvet, D.; Dafni, T.; Diago, A.; Druillole, F.; Fanourakis, G.; Ferrer-Ribas, E.; Galán, J.; García, J.A.; Gardikiotis, A.; Garza, J.G.; Geralis, T.; Giomataris, I.; Gómez, H.; González-Díaz, D.; Herrera, D.C.; Iguaz, F.J.; Irastorza, I.G.; Jourde, D.; Luzón, G.; Mirallas, H.; Mols, J.P.; Papaevangelou, T.; Rodríguez, A.; Seguí, L.; Tomás, A.; Vafeiadis, T.; Yildiz, S.C.

    2013-01-01

    Micromegas detectors are an optimum technological choice for the detection of low energy x-rays. The low background techniques applied to these detectors yielded remarkable background reductions over the years, being the CAST experiment beneficiary of these developments. In this document we report on the latest upgrades towards further background reductions and better understanding of the detectors' response. The upgrades encompass the readout electronics, a new detector design and the implementation of a more efficient cosmic muon veto system. Background levels below 10$^{-6}$keV$^{-1}$cm$^{-2}$s$^{-1}$ have been obtained at sea level for the first time, demonstrating the feasibility of the expectations posed by IAXO, the next generation axion helioscope. Some results obtained with a set of measurements conducted in the x-ray beam of the CAST Detector Laboratory will be also presented and discussed.

  1. Statistical removal of background signals from high-throughput 1H NMR line-broadening ligand-affinity screens

    International Nuclear Information System (INIS)

    Worley, Bradley; Sisco, Nicholas J.; Powers, Robert

    2015-01-01

    NMR ligand-affinity screens are vital to drug discovery, are routinely used to screen fragment-based libraries, and used to verify chemical leads from high-throughput assays and virtual screens. NMR ligand-affinity screens are also a highly informative first step towards identifying functional epitopes of unknown proteins, as well as elucidating the biochemical functions of protein–ligand interaction at their binding interfaces. While simple one-dimensional 1 H NMR experiments are capable of indicating binding through a change in ligand line shape, they are plagued by broad, ill-defined background signals from protein 1 H resonances. We present an uncomplicated method for subtraction of protein background in high-throughput ligand-based affinity screens, and show that its performance is maximized when phase-scatter correction is applied prior to subtraction

  2. Nova performance at ultra high fluence levels

    International Nuclear Information System (INIS)

    Hunt, J.T.

    1986-01-01

    Nova is a ten beam high power Nd:glass laser used for interial confinement fusion research. It was operated in the high power high energy regime following the completion of construction in December 1984. During this period several interesting nonlinear optical phenomena were observed. These phenomena are discussed in the text. 11 refs., 5 figs

  3. Effect of high hydrostatic pressure processing on the background microbial loads and quality of cantaloupe puree

    Science.gov (United States)

    The objective of this study was to investigate and evaluate the effects of high hydrostatic pressure (HHP) applied to cantaloupe puree (CP) on microbial loads and product quality during storage for 10 days at 4 degrees C. Freshly prepared, double sealed and double bagged CP (ca. 5 g) was pressure tr...

  4. Quantification of DNA repair capacity (DRC) in peripheral blood lymphocytes of individuals from natural high background radiation areas of Kerala, India

    International Nuclear Information System (INIS)

    Vivek Kumar, P.R.; Seshadri, M.

    2011-01-01

    Human populations residing in the coastal areas of Kerala from Neendakara in south to Purakkad in north receive high level natural background radiation primarily due to the presence of thorium ( 232 Th) in the monazite containing beach sand. This provides a unique opportunity to investigate the health effects of natural high level radiation on humans. Earlier studies from our laboratory in newborns for incidence of congenital malformations, structural and numerical chromosome aberrations failed to show any significant health or biological effects due to high level natural radiation exposure. The current study used alkaline single cell gel electrophoresis (comet) assay due to its sensitivity, speed, flexibility and low cost. Biological effects of low level natural radiation was studied by assessing individual's DNA Repair Capacity (DRC), which is essential for maintaining the genome integrity. DNA damage was estimated in terms of DNA strand breaks per million base pairs (SB/106 bp). In our earlier study using comet assay, DNA SBs increased with age in subjects from normal background radiation area (NBRA). However, significant inverse correlation was observed in subjects from high background radiation area (HBRA). Further, spontaneous DNA SBs in elderly subjects (? 41 years) from HBRA was significantly lower compared to the subjects from NBRA. The present study was carried out in 90 healthy adult male subjects of which, 63 subjects belonged to HBRA and 27 subjects from NBRA. The annual effective dose in HBRA subjects was 5.87 ± 4.17 mSv year-1 (Mean ± S.D., range 1.07-17.41) and in NBRA subjects was ? 1mSv year-1. Peripheral blood lymphocytes from these individuals were irradiated with 4Gy of 60 Co gamma rays (1.4Gy/minute, Low dose irradiator 2000, BRIT, India) and DNA repair was assessed at 30 minutes. As the results were not normally distributed, the data were log transformed to normalize variance. Regression analysis was carried out to determine the relative

  5. A Comprehensive Study of Agricultural Drought Resistance and Background Drought Levels in Five Main Grain-Producing Regions of China

    OpenAIRE

    Lei Kang; Hongqi Zhang

    2016-01-01

    Drought control and resistance affect national food security. With this in mind, we studied five main grain-producing regions of China: Sanjiang Plain, Songnen Plain, Huang-Huai-Hai Plain, the middle Yangtze River and Jianghuai region and Sichuan Basin. Using GIS technology, we evaluated the comprehensive agricultural drought situation based on major crops, the basic drought resistance by integrating multiple indicators and the comprehensive drought resistance against background agricultural ...

  6. Natural radionuclide and radiological assessment of building materials in high background radiation areas of Ramsar, Iran.

    Science.gov (United States)

    Bavarnegin, Elham; Moghaddam, Masoud Vahabi; Fathabadi, Nasrin

    2013-04-01

    Building materials, collected from different sites in Ramsar, a northern coastal city in Iran, were analyzed for their natural radionuclide contents. The measurements were carried out using a high resolution high purity Germanium (HPGe) gamma-ray spectrometer system. The activity concentration of (226)Ra, (232)Th, and (40)K content varied from below the minimum detection limit up to 86,400 Bqkg(-1), 187 Bqkg(-1), and 1350 Bqkg(-1), respectively. The radiological hazards incurred from the use of these building materials were estimated through various radiation hazard indices. The result of this survey shows that values obtained for some samples are more than the internationally accepted maximum limits and as such, the use of them as a building material pose significant radiation hazard to individuals.

  7. High bicarbonate levels in narcoleptic children.

    Science.gov (United States)

    Franco, Patricia; Junqua, Aurelie; Guignard-Perret, Anne; Raoux, Aude; Perier, Magali; Raverot, Veronique; Claustrat, Bruno; Gustin, Marie-Paule; Inocente, Clara Odilia; Lin, Jian-Sheng

    2016-04-01

    The objective of this study was to evaluate the levels of plasma bicarbonate levels in narcoleptic children. Clinical, electrophysiological data and bicarbonate levels were evaluated retrospectively in children seen in our paediatric national reference centre for hypersomnia. The cohort included 23 control subjects (11.5 ± 4 years, 43% boys) and 51 patients presenting de-novo narcolepsy (N) (12.7 ± 3.7 years, 47% boys). In narcoleptic children, cataplexy was present in 78% and DQB1*0602 was positive in 96%. The control children were less obese (2 versus 47%, P = 0.001). Compared with control subjects, narcoleptic children had higher bicarbonate levels (P = 0.02) as well as higher PCO2 (P < 0.01) and lower venous pH gas (P < 0.01). Bicarbonate levels higher than 27 mmol L(-1) were found in 41.2% of the narcoleptic children and 4.2% of the controls (P = 0.001). Bicarbonate levels were correlated with the Adapted Epworth Sleepiness Scale (P = 0.01). Narcoleptic patients without obesity often had bicarbonate levels higher than 27 mmol L (-1) (55 versus 25%, P = 0.025). No differences were found between children with and without cataplexy. In conclusion, narcoleptic patients had higher bicarbonate plasma levels compared to control children. This result could be a marker of hypoventilation in this pathology, provoking an increase in PCO2 and therefore a respiratory acidosis, compensated by an increase in plasma bicarbonates. This simple screening tool could be useful for prioritizing children for sleep laboratory evaluation in practice. © 2015 European Sleep Research Society.

  8. Vision in high-level football officials.

    Science.gov (United States)

    Baptista, António Manuel Gonçalves; Serra, Pedro M; McAlinden, Colm; Barrett, Brendan T

    2017-01-01

    Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of pfootball officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual

  9. Effects of Iron Concentration Level in Extracting Solutions from Contaminated Soils on the Determination of Zinc by Flame Atomic Absorption Spectrometry with Two Background Correctors

    Directory of Open Access Journals (Sweden)

    Christophe Waterlot

    2012-01-01

    Full Text Available Zinc and iron concentrations were determined after digestion, water, and three-step sequential extractions of contaminated soils. Analyses were carried out using flame absorption spectrometry with two background correctors: a deuterium lamp used as the continuum light source (D2 method and the high-speed self-reversal method (HSSR method. Regarding the preliminary results obtained with synthetic solutions, the D2 method often emerged as an unsuitable configuration for compensating iron spectral interferences. In contrast, the HSSR method appeared as a convenient and powerful configuration and was tested for the determination of zinc in contaminated soils containing high amounts of iron. Simple, fast, and interference-free method, the HSSR method allows zinc determination at the ppb level in the presence of large amounts of iron with high stability, sensitivity, and reproducibility of results. Therefore, the HSSR method is described here as a promising approach for monitoring zinc concentrations in various iron-containing samples without any pretreatment.

  10. Conditioning the gamma spectrometer for activity measurement at very high background

    OpenAIRE

    Yan, Weihua; Zhang, Liguo; Zhang, Zhao; Xiao, Zhigang

    2013-01-01

    The application of a high purity germanium (HPGe) gamma spectrometer in determining the fuel element burnup in a future reactor is studied. The HPGe detector is exposed by a Co60 source with varying irradiation rate from 10 kcps to 150 kcps to simulate the input counting rate in real reactor environment. A Cs137 and a Eu152 source are positioned at given distances to generate certain event rate in the detector with the former being proposed as a labeling nuclide to measure the burnup of fuel ...

  11. Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

    International Nuclear Information System (INIS)

    Morishima, Hiroshige; Koga, Taeko; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2000-01-01

    As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

  12. Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

    Energy Technology Data Exchange (ETDEWEB)

    Morishima, Hiroshige; Koga, Taeko [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2000-10-01

    As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

  13. Vision in high-level football officials.

    Directory of Open Access Journals (Sweden)

    António Manuel Gonçalves Baptista

    Full Text Available Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R and assistant referees (AR participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9% and ten of the 49 ARs (20.4% were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS and the Quality-of-Vision (QoV questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis were gathered in a subset (n = 44, 62% of the participants. Data were analysed according to the type (R/AR and level (international/national of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of p<0.01, PVVS scores did not differ between R and AR (p = 0.88, or between national- and international-level officials (p = 0.66. Similarly, QoV scores did not differ between R and AR in frequency (p = 0.50, severity (p = 0.71 or bothersomeness (p = 0.81 of symptoms, or between international-level vs national-level officials for frequency (p = 0.03 or bothersomeness (p = 0.07 of symptoms. However, international-level officials reported less severe symptoms than their national-level counterparts (p<0.01. Overall, 18.3% of officials had either never had an eye examination or if they had, it was more than 3 years previously. Regarding refractive correction, 4.2% had undergone refractive surgery and

  14. Statistics of high-level scene context.

    Science.gov (United States)

    Greene, Michelle R

    2013-01-01

    CONTEXT IS CRITICAL FOR RECOGNIZING ENVIRONMENTS AND FOR SEARCHING FOR OBJECTS WITHIN THEM: contextual associations have been shown to modulate reaction time and object recognition accuracy, as well as influence the distribution of eye movements and patterns of brain activations. However, we have not yet systematically quantified the relationships between objects and their scene environments. Here I seek to fill this gap by providing descriptive statistics of object-scene relationships. A total of 48, 167 objects were hand-labeled in 3499 scenes using the LabelMe tool (Russell et al., 2008). From these data, I computed a variety of descriptive statistics at three different levels of analysis: the ensemble statistics that describe the density and spatial distribution of unnamed "things" in the scene; the bag of words level where scenes are described by the list of objects contained within them; and the structural level where the spatial distribution and relationships between the objects are measured. The utility of each level of description for scene categorization was assessed through the use of linear classifiers, and the plausibility of each level for modeling human scene categorization is discussed. Of the three levels, ensemble statistics were found to be the most informative (per feature), and also best explained human patterns of categorization errors. Although a bag of words classifier had similar performance to human observers, it had a markedly different pattern of errors. However, certain objects are more useful than others, and ceiling classification performance could be achieved using only the 64 most informative objects. As object location tends not to vary as a function of category, structural information provided little additional information. Additionally, these data provide valuable information on natural scene redundancy that can be exploited for machine vision, and can help the visual cognition community to design experiments guided by statistics

  15. Preliminary analysis of data (1987-1990) from investigation of cancer mortality in high background radiation area of Yangjiang, China

    International Nuclear Information System (INIS)

    Tao Zufan; Sun Quanfu; Zhang Shouzhi

    1997-01-01

    Objective: The cancer mortality study conducted in the high background radiation area (HBRA) of Yangjiang, China, was started in 1972. The major objective of the study was to estimate cancer risk associated with the low level radiation exposure in HBRA. Since 1991, the cancer mortality data were collected from a fixed cohort instead of a dynamic one as in the previous stage. The purpose of the study in the current stage was to accumulate further person-years (Pyr) of observation for improving the statistical power of test in the estimates of cancer risk associated with the natural radiation exposure and to see the reproducibility of the previous results. Methods: The collection of cancer mortality data consisted of two phases, the survey of demography and the ascertainment of death causes. The estimates of relative risk (RR) were calculated by AMFIT in Epicure (Hirosoft International Corp., 1988-1992). Results: During the period of 1987-1990 there were 231 cancer deaths among 421640 Pyr at risk in the cohort of 106517 subjects, which were classified into four groups based on the hamlet-specific average annual gamma ray absorbed doses: three groups (high , medial and low doses) from HBRA and control group from CA. The RRs adjusted for sex and age for each dose group in HBRA compared with the control group for overall cancers and for all cancers except leukemia were less than 1 except for the low dose group, and there seemed to be a trend of RR decrease with the increase of exposure dose from natural radiation, though there was no statistically significant difference. As for the site-specific cancer studied, the cancers of lungs, liver, stomach, nasopharynx and leukemia, the RRs were also less than 1 except for nasopharynx cancer and for leukemia in the high dose group. The analysis of combined data ( 1979-1990) showed similar results. Conclusion: Although the sample size was not large enough to make definite conclusion statistically, the observation of current

  16. Assessment of immune surveillance among inhabitants of high natural background radiation areas in Ramsar-Iran

    International Nuclear Information System (INIS)

    Sileh, Sajad Borzouei; Monfared, Ali Shabestani; Mostafazade, Amrollah; Abedian, Said

    2010-01-01

    In this study by Multi-parameter flow cytometry, immunologic analyze is performed on peripheral blood, NK cells, most effective cells in innate immune and the proportion of TCD8/TCD4 cells that is effective in cellular immune system will be determined. Lysosomal-associated membrane protein-1 (LAMP-1 or CD107a) is used as a functional marker for the identification of natural killer cell activity. Immune surveillance and immune system role in tumoral defense in Ramsar inhabitants will be determined. Radiation dose rate in Talesh mahalle is very high and was many times greater than Chaparsar (another region in Ramsar). Immune surveillance and immune system role in tumoral defense in Talesh mahalle inhabitants will be compared to Chaparsar inhabitants. If this doesn't have significant difference, we should think about some other aspects such as free radical scavengers that will study later

  17. State of the art of D ampersand D Instrumentation Technology: Alpha counting in the presence of high background

    International Nuclear Information System (INIS)

    Dickerman, C.E.

    1995-08-01

    Discrimination of alpha activity in the presence of a high radiation background has been identified as an area of concern to be studied for D ampersand D applications. Upon evaluating the range of alpha detection needs for D ampersand D operations, we have expanded this study to address the operational concern of greatly expediting alpha counting of rough surfaces and rubble. Note that the term, ''rough surfaces'' includes a wide range of practical cases, including contaminated equipment and work surfaces. We have developed provisional applications requirements for instrumentation of this type; and we also have generated the scope of a program of instrument evaluation and testing, with emphasis on practical implementation. In order to obtain the full operational benefit of alpha discrimination in the presence of strong beta-gamma radiation background, the detection system must be capable of some form of remote or semi-remote operation in order to reduce operator exposure. We have identified a highly promising technique, the long-range alpha detector (LRAD), for alpha discrimination in the presence of high radiation background. This technique operates upon the principle of transporting alphaionized air to an ionization detector. A transport time within a few seconds is adequate. Neither the provisional requirements nor the evaluation and testing scope were expressly tailored to force the selection of a LRAD technology, and they could be used as a basis for studies of other promising technologies. However, a technology that remotely detects alpha-ionized air (e. g., LRAD) is a natural fit to the key requirements of rejection of high background at the survey location and operator protection. Also, LRAD appears to be valuable for D ampersand D applications as a means of greatly expediting surface alpha-activity surveys that otherwise would require performing time-consuming scans over surfaces of interest with alpha detector probes, and even more labor-intensive surface

  18. Estimation and comparison of baseline frequencies of micronuclei among the new-borns from natural high background radiation and control areas of Kerala coast in south India

    International Nuclear Information System (INIS)

    Das, Birajalaxmi; Karuppasamy, C.V.; Thampi, M.V.

    1994-01-01

    Based on the studies it is concluded that the elevated level of natural radiation has no significant effect of micronucleus formation in high background radiation area (HBRA) new-borns as compared to control area. It is also in agreement with the results of cytogenetic investigations on new-borns from HBRA and control area using chromosome aberration analysis method. The significance, if any, of the slightly lower micronuclei (MN) frequency observed in HBRA, is not clear at this stage. Further investigations on a larger number of new-borns from both the areas are necessary in order to draw firm conclusions. It appears that, this is the first attempt to estimate the baseline frequency of MN among the new-borns from a natural high background radiation area. (author). 9 refs

  19. On risk assessment of high level radioactive waste disposal

    International Nuclear Information System (INIS)

    Smith, C.F.; Kastenberg, W.E.

    1976-01-01

    One of the major concerns with the continued growth of the nuclear power industry is the production of the high level radioactive wastes. The risks associated with the disposal of these wastes derives from the potential for release of radioactive materials into the environment. The development of a methodology for risk analysis is carried out. The methodology suggested involves the probabilistic analysis of a general accident consequence distribution. In this analysis, the frequency aspect of the distribution is treated separately from the normalized probability function. In the final stage of the analysis, the frequency and probability characteristics of the distribution are recombined to provide an estimate of the risk. The characterization of the radioactive source term is accomplished using the ORIGEN computer code. Calculations are carried out for various reactor types and fuel cycles, and the overall waste hazard for a projected 35 year nuclear power program is determined. An index of relative nuclide hazard appropriate to problems involving the management of high level radioactive wastes is developed. As an illustration of the methodology, risk analyses are made for two proposed methods for waste management: extraterrestrial disposal and interim surface storage. The results of these analyses indicate that, within the assumptions used, the risks of these management schemes are small compared with natural background radiation doses. (Auth.)

  20. Spent Fuel and High-Level Radioactive Waste Transportation Report

    International Nuclear Information System (INIS)

    1992-03-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by SSEB in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ''comprehensive overview of the issues.'' This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste Issues. In addition. this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list

  1. Spent fuel and high-level radioactive waste transportation report

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages sew be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

  2. Spent fuel and high-level radioactive waste transportation report

    International Nuclear Information System (INIS)

    1989-11-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ''comprehensive overview of the issues.'' This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages sew be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list

  3. Spent fuel and high-level radioactive waste transportation report

    International Nuclear Information System (INIS)

    1990-11-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ''comprehensive overview of the issues.'' This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list

  4. Progress in the High Level Trigger Integration

    CERN Multimedia

    Cristobal Padilla

    2007-01-01

    During the week from March 19th to March 23rd, the DAQ/HLT group performed another of its technical runs. On this occasion the focus was on integrating the Level 2 and Event Filter triggers, with a much fuller integration of HLT components than had been done previously. For the first time this included complete trigger slices, with a menu to run the selection algorithms for muons, electrons, jets and taus at the Level-2 and Event Filter levels. This Technical run again used the "Pre-Series" system (a vertical slice prototype of the DAQ/HLT system, see the ATLAS e-news January issue for details). Simulated events, provided by our colleagues working in the streaming tests, were pre-loaded into the ROS (Read Out System) nodes. These are the PC's where the data from the detector is stored after coming out of the front-end electronics, the "first part of the TDAQ system" and the interface to the detectors. These events used a realistic beam interaction mixture and had been subjected to a Level-1 selection. The...

  5. High background radiation area: an important source of exploring the health effects of low dose ionizing radiation

    International Nuclear Information System (INIS)

    Wei Luxin

    1997-01-01

    Objective: For obtaining more effective data from epidemiological investigation in high background radiation areas, it is necessary to analyze the advantages, disadvantages, weak points and problems of this kind of radiation research. Methods: For epidemiological investigation of population health effects of high background radiation, the author selected high background radiation areas of Yangjiang (HBRA) and a nearby control area (CA) as an instance for analysis. The investigation included classification of dose groups, comparison of the confounding factors in the incidence of mutation related diseases, cancer mortalities and the frequencies of chromosomal aberrations between HBRA and CA. This research program has become a China-Japan cooperative research since 1991. Results: The confounding factors above-mentioned were comparable between HBRA and CA, and within the dose groups in HBRA, based on a systematic study for many years. The frequencies of chromosomal aberrations increased with the increase of cumulative dose, but not for children around or below 10 years of age. The relative risks (RR) of total and site-specific cancer mortalities for HBRA were lower or around 1.00, compared with CA. The incidence of hereditary diseases and congenital deformities in HBRA were in normal range. The results were interpreted preliminarily by the modified 'dual radiation action' theory and the 'benefit-detriment competition' hypothesis. Conclusions: The author emphasizes the necessity for continuing epidemiological research in HBRA, especially for international cooperation. He also emphasizes the importance of combination of epidemiology and radiobiology

  6. Memory performance on the Auditory Inference Span Test is independent of background noise type for young adults with normal hearing at high speech intelligibility.

    Science.gov (United States)

    Rönnberg, Niklas; Rudner, Mary; Lunner, Thomas; Stenfelt, Stefan

    2014-01-01

    Listening in noise is often perceived to be effortful. This is partly because cognitive resources are engaged in separating the target signal from background noise, leaving fewer resources for storage and processing of the content of the message in working memory. The Auditory Inference Span Test (AIST) is designed to assess listening effort by measuring the ability to maintain and process heard information. The aim of this study was to use AIST to investigate the effect of background noise types and signal-to-noise ratio (SNR) on listening effort, as a function of working memory capacity (WMC) and updating ability (UA). The AIST was administered in three types of background noise: steady-state speech-shaped noise, amplitude modulated speech-shaped noise, and unintelligible speech. Three SNRs targeting 90% speech intelligibility or better were used in each of the three noise types, giving nine different conditions. The reading span test assessed WMC, while UA was assessed with the letter memory test. Twenty young adults with normal hearing participated in the study. Results showed that AIST performance was not influenced by noise type at the same intelligibility level, but became worse with worse SNR when background noise was speech-like. Performance on AIST also decreased with increasing memory load level. Correlations between AIST performance and the cognitive measurements suggested that WMC is of more importance for listening when SNRs are worse, while UA is of more importance for listening in easier SNRs. The results indicated that in young adults with normal hearing, the effort involved in listening in noise at high intelligibility levels is independent of the noise type. However, when noise is speech-like and intelligibility decreases, listening effort increases, probably due to extra demands on cognitive resources added by the informational masking created by the speech fragments and vocal sounds in the background noise.

  7. High level secretion of cellobiohydrolases by Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Ahlgren Simon

    2011-09-01

    Full Text Available Abstract Background The main technological impediment to widespread utilization of lignocellulose for the production of fuels and chemicals is the lack of low-cost technologies to overcome its recalcitrance. Organisms that hydrolyze lignocellulose and produce a valuable product such as ethanol at a high rate and titer could significantly reduce the costs of biomass conversion technologies, and will allow separate conversion steps to be combined in a consolidated bioprocess (CBP. Development of Saccharomyces cerevisiae for CBP requires the high level secretion of cellulases, particularly cellobiohydrolases. Results We expressed various cellobiohydrolases to identify enzymes that were efficiently secreted by S. cerevisiae. For enhanced cellulose hydrolysis, we engineered bimodular derivatives of a well secreted enzyme that naturally lacks the carbohydrate-binding module, and constructed strains expressing combinations of cbh1 and cbh2 genes. Though there was significant variability in the enzyme levels produced, up to approximately 0.3 g/L CBH1 and approximately 1 g/L CBH2 could be produced in high cell density fermentations. Furthermore, we could show activation of the unfolded protein response as a result of cellobiohydrolase production. Finally, we report fermentation of microcrystalline cellulose (Avicel™ to ethanol by CBH-producing S. cerevisiae strains with the addition of beta-glucosidase. Conclusions Gene or protein specific features and compatibility with the host are important for efficient cellobiohydrolase secretion in yeast. The present work demonstrated that production of both CBH1 and CBH2 could be improved to levels where the barrier to CBH sufficiency in the hydrolysis of cellulose was overcome.

  8. Period analysis at high noise level

    International Nuclear Information System (INIS)

    Kovacs, G.

    1980-01-01

    Analytical expressions are derived for the variances of some types of the periodograms due to normal-distributed noise present in the data. The equivalence of the Jurkevich and the Warner and Robinson methods is proved. The optimum phase cell number of the Warner and Robinson method is given; this number depends on the data length, signal form and noise level. The results are illustrated by numerical examples. (orig.)

  9. Disposal of high-level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Costello, J M [Australian Atomic Energy Commission Research Establishment, Lucas Heights

    1982-03-01

    The aims and options for the management and disposal of highly radioactive wastes contained in spent fuel from the generation of nuclear power are outlined. The status of developments in reprocessing, waste solidification and geologic burial in major countries is reviewed. Some generic assessments of the potential radiological impacts from geologic repositories are discussed, and a perspective is suggested on risks from radiation.

  10. High-lying 0+ and 3- levels in 12C

    International Nuclear Information System (INIS)

    Hanna, S.S.; Feldman, W.; Suffert, M.; Kurath, D.

    1982-01-01

    The γ decays of the levels at 17.77 and 18.36 MeV in 12 C are studied by proton capture and the assignments of (0 + ,1) and (3 - ,1), respectively, are confirmed. The very great strength of the decay of the (0 + ,1) level to the lower (1 + ,0) level at 12.71 MeV is consistent with a spin- and isospin-flip deuteronlike transition. The strong decay of the (3 - ,1) level to the lower (3 - 0,) level at 9.64 MeV is fairly typical of an analog to antianalog transition. The γ-decay widths of these levels are compared with shell-model calculations

  11. Background levels of some trace elements in sandy soil of Abou-Zabal, and its variation with soil depth determines by neutron activation analysis. Vol. 4

    International Nuclear Information System (INIS)

    Abdel-Sabour, M.F.; Sanad, W.; Flex, H.; Abdel-Haleem, A.S.; Zohny, E.

    1996-01-01

    The variation in soil total heavy metal contents (horizontally and vertically) in small land area (about one acre) was investigated using neutron activities analysis technique. The background levels found in the sandy soil of Abou-Zabal are also discussed in relation to the findings of other workers. 5 tabs

  12. Background levels of some trace elements in sandy soil of Abou-Zabal, and its variation with soil depth determines by neutron activation analysis. Vol. 4.

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Sabour, M F [Soil Pollution Unit, Soil and Water Department. Nuclear Research Center, Atomic energy Authority, Cairo, (Egypt); Sanad, W; Flex, H; Abdel-Haleem, A S [Hot Lab. Center, Atomic Energy Authority, Cairo (Egypt); Zohny, E [Physics Department, Faculty of Science, Cairo Univ., Beni-Sweif Branch, Cairo, (Egypt)

    1996-03-01

    The variation in soil total heavy metal contents (horizontally and vertically) in small land area (about one acre) was investigated using neutron activities analysis technique. The background levels found in the sandy soil of Abou-Zabal are also discussed in relation to the findings of other workers. 5 tabs.

  13. [Eating Disorders in Female High School Students: Educational and Migration Background, School-Related Stress and Performance-Orientated Classes].

    Science.gov (United States)

    Grüttner, M

    2018-02-01

    Many adolescents and young adults, especially young females, suffer from eating disorders or problematic nutrition behavior. Children and adolescents with migration background as well as from a lower social class are more likely to have eating disorders 1. Although schools are an important context in these age groups, there is a lack of scientific inquiry concerning the relationship between schooling and eating disorders. The present study investigates the relationship between performance-related stress at school and eating disorders while controlling for personnel and familial resources. Interview data on the 7 th grade high school students from the National Educational Panel Study (NEPS)* starting cohort 3 are used. The dependent variable is based on the SCOFF questionnaire. Logistic regressions are calculated using information from students and parents. Performance-related stress at school is operationalized by the negative deviation of realistic from idealistic educational aspirations (EA) and unfulfilled social expectations (SE), performance-oriented class climate is operationalized by students' perception of the performance-orientation of the teacher (PT) and the expectations of classmates (EC). The results point towards an increased risk of suffering from an eating disorder due to performance-related school stress (EA: AME: 0.18; p<0.001; SE: AME: 0.12; p<0.05) and performance-oriented class climate (PT: AME: 0.05; p<0.1; EC: AME: 0.15, p<0.01). They partly explain the relation between both migration background and educational background and eating disorders. In order to prevent eating disorders in female high school students, attention should be paid to performance-orientation experienced at school and in the social background, and improved individual support for disadvantaged students should be made available. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Different levels of UV-B resistance in Vaccinium corymbosum cultivars reveal distinct backgrounds of phenylpropanoid metabolites.

    Science.gov (United States)

    Luengo Escobar, Ana; Magnum de Oliveira Silva, Franklin; Acevedo, Patricio; Nunes-Nesi, Adriano; Alberdi, Miren; Reyes-Díaz, Marjorie

    2017-09-01

    UV-B radiation induces several physiological and biochemical effects that can influence regulatory plant processes. Vaccinium corymbosum responds differently to UV-B radiation depending on the UV-B resistance of cultivars, according to their physiological and biochemical features. In this work, the effect of two levels of UV-B radiation during long-term exposure on the phenylpropanoid biosynthesis, and the expression of genes associated with flavonoid biosynthesis as well as the absolute quantification of secondary metabolites were studied in two contrasting UV-B-resistant cultivars (Legacy, resistant and Bluegold, sensitive). Multivariate analyses were performed to understand the role of phenylpropanoids in UV-B defense mechanisms. The amount of phenylpropanoid compounds was generally higher in Legacy than in Bluegold. Different expression levels of flavonoid biosynthetic genes for both cultivars were transiently induced, showing that even in longer period of UV-B exposure; plants are still adjusting their phenylpropanoids at the transcription levels. Multivariate analysis in Legacy indicated no significant correlation between gene expression and the levels of the flavonoids and phenolic acids. By contrast, in the Bluegold cultivar higher number of correlations between secondary metabolite and transcript levels was found. Taken together, the results indicated different adjustments between the cultivars for a successful UV-B acclimation. While the sensitive cultivar depends on metabolite adjustments to respond to UV-B exposure, the resistant cultivar also possesses an intrinsically higher antioxidant and UV-B screening capacity. Thus, we conclude that UV-B resistance involves not only metabolite level adjustments during the acclimation period, but also depends on the intrinsic metabolic status of the plant and metabolic features of the phenylpropanoid compounds. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. High level radiation dosimetry in biomedical research

    International Nuclear Information System (INIS)

    Inada, Tetsuo

    1979-01-01

    The physical and biological dosimetries relating to cancer therapy with radiation were taken up at the first place in the late intercomparison on high LET radiation therapy in Japan-US cancer research cooperative study. The biological dosimetry, the large dose in biomedical research, the high dose rate in biomedical research and the practical dosimeters for pulsed neutrons or protons are outlined with the main development history and the characteristics which were obtained in the relating experiments. The clinical neutron facilities in the US and Japan involved in the intercomparison are presented. Concerning the experimental results of dosimeters, the relation between the R.B.E. compared with Chiba (Cyclotron in National Institute of Radiological Sciences) and the energy of deuterons or protons used for neutron production, the survival curves of three cultured cell lines derived from human cancers, after the irradiation of 250 keV X-ray, cyclotron neutrons of about 13 MeV and Van de Graaff neutrons of about 2 MeV, the hatchability of dry Artemia eggs at the several depths in an absorber stack irradiated by 60 MeV proton beam of 40, 120 and 200 krad, the peak skin reaction of mouse legs observed at various sets of average and instantaneous dose rates, and the peak skin reaction versus three instantaneous dose rates at fixed average dose rate of 7,300 rad/min are shown. These actual data were evaluated numerically and in relation to the physical meaning from the viewpoint of the fundamental aspect of cancer therapy, comparing the Japanese measured values to the US data. The discussion record on the high dose rate effect of low LET particles on biological substances and others is added. (Nakai, Y.)

  16. Energy levels of highly ionized atoms

    International Nuclear Information System (INIS)

    Martin, W.C.

    1981-01-01

    Most of the data reviewed here were derived from spectra photographed in the wavelength range from 600 A down to about 20 A (approx. 20 to 600 eV). Measurements with uncertainties less than 0.001 A relative to appropriate standard wavelengths can be made with high-resolution diffraction-grating spectroscopy over most of the vacuum-ultraviolet region. Although this uncertainty corresponds to relative errors of 1 part per million (ppM) at 1000 A and 20 ppM at 50 A, measurements with uncertainties smaller than 0.001 A would generally require more effort at the shorter wavelengths, mainly because of the sparsity of accurate standards. Even where sufficiently numerous and accurate standards are available, the accuracy of measurements of the spectra of very high temperature plasmas is limited by Doppler broadening and, in some cases, other plasma effects. Several sources of error combine to give total estimated errors ranging from 10 to 1000 ppM for the experimental wavelengths of interest here. It will be seen, however, that with the possible exception of a few fine-structure splittings the experimental errors are small compared to the errors of the relevant theoretical calculations

  17. Memory performance on the Auditory Inference Span Test is independent of background noise type for young adults with normal hearing at high speech intelligibility

    Directory of Open Access Journals (Sweden)

    Niklas eRönnberg

    2014-12-01

    Full Text Available Listening in noise is often perceived to be effortful. This is partly because cognitive resources are engaged in separating the target signal from background noise, leaving fewer resources for storage and processing of the content of the message in working memory. The Auditory Inference Span Test (AIST is designed to assess listening effort by measuring the ability to maintain and process heard information. The aim of this study was to use AIST to investigate the effect of background noise types and signal-to-noise ratio (SNR on listening effort, as a function of working memory capacity (WMC and updating ability (UA. The AIST was administered in three types of background noise: steady-state speech-shaped noise, amplitude modulated speech-shaped noise, and unintelligible speech. Three SNRs targeting 90% speech intelligibility or better were used in each of the three noise types, giving nine different conditions. The reading span test assessed WMC, while UA was assessed with the letter memory test. Twenty young adults with normal hearing participated in the study. Results showed that AIST performance was not influenced by noise type at the same intelligibility level, but became worse with worse SNR when background noise was speech-like. Performance on AIST also decreased with increasing MLL. Correlations between AIST performance and the cognitive measurements suggested that WMC is of more importance for listening when SNRs are worse, while UA is of more importance for listening in easier SNRs. The results indicated that in young adults with normal hearing, the effort involved in listening in noise at high intelligibility levels is independent of the noise type. However, when noise is speech-like and intelligibility decreases, listening effort increases, probably due to extra demands on cognitive resources added by the informational masking created by the speech-fragments and vocal sounds in the background noise.

  18. Seasonal changes in background levels of deuterium and oxygen-18 prove water drinking by harp seals, which affects the use of the doubly labelled water method.

    Science.gov (United States)

    Nordøy, Erling S; Lager, Anne R; Schots, Pauke C

    2017-12-01

    The aim of this study was to monitor seasonal changes in stable isotopes of pool freshwater and harp seal ( Phoca groenlandica ) body water, and to study whether these potential seasonal changes might bias results obtained using the doubly labelled water (DLW) method when measuring energy expenditure in animals with access to freshwater. Seasonal changes in the background levels of deuterium and oxygen-18 in the body water of four captive harp seals and in the freshwater pool in which they were kept were measured over a time period of 1 year. The seals were offered daily amounts of capelin and kept under a seasonal photoperiod of 69°N. Large seasonal variations of deuterium and oxygen-18 in the pool water were measured, and the isotope abundance in the body water showed similar seasonal changes to the pool water. This shows that the seals were continuously equilibrating with the surrounding water as a result of significant daily water drinking. Variations in background levels of deuterium and oxygen-18 in freshwater sources may be due to seasonal changes in physical processes such as precipitation and evaporation that cause fractionation of isotopes. Rapid and abrupt changes in the background levels of deuterium and oxygen-18 may complicate calculation of energy expenditure by use of the DLW method. It is therefore strongly recommended that analysis of seasonal changes in background levels of isotopes is performed before the DLW method is applied on (free-ranging) animals, and to use a control group in order to correct for changes in background levels. © 2017. Published by The Company of Biologists Ltd.

  19. DESIRE FOR LEVELS. Background study for the policy document "Setting Environmental Quality Standards for Water and Soil"

    NARCIS (Netherlands)

    van de Meent D; Aldenberg T; Canton JH; van Gestel CAM; Slooff W

    1990-01-01

    The report provides scientific support for setting environmental quality objectives for water, sediment and soil. Quality criteria are not set in this report. Only options for decisions are given. The report is restricted to the derivation of the 'maximally acceptable risk' levels (MAR)

  20. The High Level Vibration Test Program

    International Nuclear Information System (INIS)

    Hofmayer, C.H.; Curreri, J.R.; Park, Y.J.; Kato, W.Y.; Kawakami, S.

    1989-01-01

    As part of cooperative agreements between the United States and Japan, tests have been performed on the seismic vibration table at the Tadotsu Engineering Laboratory of Nuclear Power Engineering Test Center (NUPEC) in Japan. The objective of the test program was to use the NUPEC vibration table to drive large diameter nuclear power piping to substantial plastic strain with an earthquake excitation and to compare the results with state-of-the-art analysis of the problem. The test model was designed by modifying the 1/2.5 scale model of the PWR primary coolant loop. Elastic and inelastic seismic response behavior of the test model was measured in a number of test runs with an increasing excitation input level up to the limit of the vibration table. In the maximum input condition, large dynamic plastic strains were obtained in the piping. Crack initiation was detected following the second maximum excitation run. The test model was subjected to a maximum acceleration well beyond what nuclear power plants are designed to withstand. This paper describes the overall plan, input motion development, test procedure, test results and comparisons with pre-test analysis. 4 refs., 16 figs., 2 tabs

  1. The High Level Vibration Test program

    International Nuclear Information System (INIS)

    Hofmayer, C.H.; Curreri, J.R.; Park, Y.J.; Kato, W.Y.; Kawakami, S.

    1990-01-01

    As part of cooperative agreements between the United States and Japan, tests have been performed on the seismic vibration table at the Tadotsu Engineering Laboratory of Nuclear Power Engineering Test Center (NUPEC) in Japan. The objective of the test program was to use the NUPEC vibration table to drive large diameter nuclear power piping to substantial plastic strain with an earthquake excitation and to compare the results with state-of-the-art analysis of the problem. The test model was designed by modifying the 1/2.5 scale model of the pressurized water reactor primary coolant loop. Elastic and inelastic seismic response behavior of the test model was measured in a number of test runs with an increasing excitation input level up to the limit of the vibration table. In the maximum input condition, large dynamic plastic strains were obtained in the piping. Crack initiation was detected following the second maximum excitation run. The test model was subjected to a maximum acceleration well beyond what nuclear power plants are designed to withstand. This paper describes the overall plan, input motion development, test procedure, test results and comparisons with pre-test analysis

  2. Four years of highly time resolved measurements of elemental and organic carbon at a rural background site in Central Europe

    Science.gov (United States)

    Mbengue, Saliou; Fusek, Michal; Schwarz, Jaroslav; Vodička, Petr; Šmejkalová, Adéla Holubová; Holoubek, Ivan

    2018-06-01

    Elemental carbon (EC) and organic carbon (OC) in fine atmospheric aerosols (PM2.5: aerodynamic diameter smaller than 2.5 μm) have been measured with a semi-automatic instrument during a 4-year survey at the National Atmospheric Observatory Košetice (NAOK), Czech Republic. Ground based measurements were performed from March 2013 to December 2016 with a field Semi-Continuous OCEC Aerosol Analyzer (Sunset Laboratory Inc., USA). The variation of EC and OC concentrations and the OC/EC ratio was characterized for different seasons and days of the week. During our survey, higher concentrations of EC and OC were observed in winter (0.83 ± 0.67 and 3.33 ± 2.28 μg m-3, respectively), and lower concentrations were recorded in summer (0.34 ± 0.18 and 2.30 ± 1.15 μg m-3, respectively). Inversely, the OC/EC ratio with mean value (5.1 ± 2.6) characteristic to rural background area was higher in summer (7.33 ± 3.23) in comparison to the other seasons. Since the data contain values below detection and quantification limits of the measuring device (i.e., censored values), statistical methods for censored data have been used in order to compare mean EC and OC concentrations between various seasons. It was found out that there is a significant difference between summer and the other seasons with the exception of mean OC concentrations at noon. In most cases, there was also a significant difference between winter and the other seasons. Moreover, it was found out that when dealing with OC concentrations, it is possible to replace censored values by a constant and still obtain reasonable results. In case of EC concentrations, the method based on censored distributions should be preferred when the sample size is small and the proportion of censored values is high. The diurnal variation of EC and OC is less pronounced in summer. During working days, the EC diurnal pattern displays a morning (between 6:00 and 10:00) and an afternoon/evening (between 18:00 and 22:00) peaks, while

  3. Assessment of indoor radiation dose received by the residents of natural high background radiation areas of coastal villages of Kanyakumari district, Tamil Nadu, India

    Energy Technology Data Exchange (ETDEWEB)

    Deva Jayanthi, D., E-mail: d.devajayanthi@gmail.co [Department of Physics, Women' s Christian College, Nagercoil 629001 (India); Maniyan, C.G. [Environmental Assessment Division, BARC, Mumbai 400085 (India); Perumal, S. [Department of Physics and Research Centre, S.T.Hindu College, Nagercoil 629002 (India)

    2011-07-15

    Radiation exposure and effective dose received through two routes of exposure, viz. external and internal, via inhalation, by residents of 10 villages belonging to Natural High Background Radiation Areas (NHBRA) of coastal regions of Kanyakumari District and Tamil Nadu in India were studied. While the indoor gamma radiation levels were monitored using Thermo Luminescent Dosimeters (TLDs), the indoor radon and thoron gas concentrations were measured using twin chamber dosimeters employing Solid State Nuclear Track Detectors (SSNTDs, LR-115-II). The average total annual effective dose was estimated and found to be varying from 2.59 to 8.76 mSv. -- Highlights: {yields} The effective dose received by the villages of Natural High Background Area (NHBRA) such as Enayam, Midalam and Mel Midalam is high when compared with other study areas. {yields} The high dose indicates higher concentration of radioactive nuclides like Thorium and Uranium in the soil. {yields} As radiation is harmful to human life, the external and internal doses can be reduced by removing the monazite content present in the soil by mineral separation. {yields} Contribution from vegetables, fruits, fish and other non vegetarian items are also being examined. {yields} These results along with other socio-economic factors can throw considerable light on the epidemiological impacts due to low levels of chronic exposure.

  4. Assessment of indoor radiation dose received by the residents of natural high background radiation areas of coastal villages of Kanyakumari district, Tamil Nadu, India

    International Nuclear Information System (INIS)

    Deva Jayanthi, D.; Maniyan, C.G.; Perumal, S.

    2011-01-01

    Radiation exposure and effective dose received through two routes of exposure, viz. external and internal, via inhalation, by residents of 10 villages belonging to Natural High Background Radiation Areas (NHBRA) of coastal regions of Kanyakumari District and Tamil Nadu in India were studied. While the indoor gamma radiation levels were monitored using Thermo Luminescent Dosimeters (TLDs), the indoor radon and thoron gas concentrations were measured using twin chamber dosimeters employing Solid State Nuclear Track Detectors (SSNTDs, LR-115-II). The average total annual effective dose was estimated and found to be varying from 2.59 to 8.76 mSv. -- Highlights: → The effective dose received by the villages of Natural High Background Area (NHBRA) such as Enayam, Midalam and Mel Midalam is high when compared with other study areas. → The high dose indicates higher concentration of radioactive nuclides like Thorium and Uranium in the soil. → As radiation is harmful to human life, the external and internal doses can be reduced by removing the monazite content present in the soil by mineral separation. → Contribution from vegetables, fruits, fish and other non vegetarian items are also being examined. → These results along with other socio-economic factors can throw considerable light on the epidemiological impacts due to low levels of chronic exposure.

  5. Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko; Morishima, Hiroshige [Kinki Univ., Atomic Energy Research Institute, Osaka (Japan); Tatsumi, Kusuo [Kinki Univ., Life Science Research Institute, Osaka (Japan); Nakai, Sayaka; Sugahara, Tsutomu [Health Research Foundation, Kyoto (Japan); Yuan Yongling [Labor Hygiene Institute of Hunan Prov. (China); Wei Luxin [Laboratory of Industorial Hygiene, Ministry of Health (China)

    2001-01-01

    As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: (1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. (2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

  6. Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

    International Nuclear Information System (INIS)

    Koga, Taeko; Morishima, Hiroshige; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2001-01-01

    As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: 1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. 2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

  7. Spatial distribution of ground-level urban background O3 concentrations in the Metropolitan Area of Buenos Aires, Argentina

    International Nuclear Information System (INIS)

    Pineda Rojas, Andrea L.; Venegas, Laura E.

    2013-01-01

    In this work, a recently developed urban-scale atmospheric dispersion model (DAUMOD-GRS) is applied to evaluate the ground-level ozone (O 3 ) concentrations resulting from anthropogenic area sources of NO x and VOC in the Metropolitan Area of Buenos Aires (MABA). The statistical comparison of model results with observations (including new available data from seventeen sites) shows a good model performance. Estimated summer highest diurnal O 3 1-h concentrations in the MABA vary between 15 ppb in the most urbanised area and 53 ppb in the suburbs. All values are below the air quality standard. Several runs are performed to evaluate the impact of possible future emission reductions on O 3 concentrations. Under all hypothetical scenarios, the maximum diurnal O 3 1-h concentration obtained for the area is slightly reduced (up to 4%). However, maximum diurnal O 3 concentrations could increase at some less urbanised areas of MABA depending on the relative reductions of the emissions of NO x and VOC. -- Highlights: ► A recently developed air quality model reproduces well observed O 3 levels in MABA. ► Modelled summer maximum diurnal O 3 concentrations vary in the area between 15 and 53 ppb. ► All hourly values are below the air quality standard (120 ppb). ► Possible future emission reductions would have small impact on the highest level. -- The distribution of summer maximum diurnal ground-level O 3 concentrations in the Metropolitan Area of Buenos Aires is evaluated applying a recently developed simple urban air quality model

  8. Heat transfer in high-level waste management

    International Nuclear Information System (INIS)

    Dickey, B.R.; Hogg, G.W.

    1979-01-01

    Heat transfer in the storage of high-level liquid wastes, calcining of radioactive wastes, and storage of solidified wastes are discussed. Processing and storage experience at the Idaho Chemical Processing Plant are summarized for defense high-level wastes; heat transfer in power reactor high-level waste processing and storage is also discussed

  9. Managing commercial high-level radioactive waste

    International Nuclear Information System (INIS)

    1983-01-01

    The article is a summary of issues raised during US Congress deliberations on nuclear waste policy legislation. It is suggested that, if history is not to repeat itself, and the current stalemate on nuclear waste is not to continue, a comprehensive policy is needed that addresses the near-term problems of interim storage as part of an explicit and credible program for dealing with the longer term problem of developing a final isolation system. Such a policy must: 1) adequately address the concerns and win the support of all the major interested parties, and 2) adopt a conservative technical and institutional approach - one that places high priority on avoiding the problems that have repeatedly beset the program in the past. It is concluded that a broadly supported comprehensive policy would contain three major elements, each designed to address one of the key questions concerning Federal credibility: commitment in law to the goals of a comprehensive policy; credible institutional mechanisms for meeting goals; and credible measures for addressing the specific concerns of the states and the various publics. Such a policy is described in detail. (Auth.)

  10. Bumblebee pupae contain high levels of aluminium.

    Science.gov (United States)

    Exley, Christopher; Rotheray, Ellen; Goulson, David

    2015-01-01

    The causes of declines in bees and other pollinators remains an on-going debate. While recent attention has focussed upon pesticides, other environmental pollutants have largely been ignored. Aluminium is the most significant environmental contaminant of recent times and we speculated that it could be a factor in pollinator decline. Herein we have measured the content of aluminium in bumblebee pupae taken from naturally foraging colonies in the UK. Individual pupae were acid-digested in a microwave oven and their aluminium content determined using transversely heated graphite furnace atomic absorption spectrometry. Pupae were heavily contaminated with aluminium giving values between 13.4 and 193.4 μg/g dry wt. and a mean (SD) value of 51.0 (33.0) μg/g dry wt. for the 72 pupae tested. Mean aluminium content was shown to be a significant negative predictor of average pupal weight in colonies. While no other statistically significant relationships were found relating aluminium to bee or colony health, the actual content of aluminium in pupae are extremely high and demonstrate significant exposure to aluminium. Bees rely heavily on cognitive function and aluminium is a known neurotoxin with links, for example, to Alzheimer's disease in humans. The significant contamination of bumblebee pupae by aluminium raises the intriguing spectre of cognitive dysfunction playing a role in their population decline.

  11. A statistical background noise correction sensitive to the steadiness of background noise.

    Science.gov (United States)

    Oppenheimer, Charles H

    2016-10-01

    A statistical background noise correction is developed for removing background noise contributions from measured source levels, producing a background noise-corrected source level. Like the standard background noise corrections of ISO 3741, ISO 3744, ISO 3745, and ISO 11201, the statistical background correction increases as the background level approaches the measured source level, decreasing the background noise-corrected source level. Unlike the standard corrections, the statistical background correction increases with steadiness of the background and is excluded from use when background fluctuation could be responsible for measured differences between the source and background noise levels. The statistical background noise correction has several advantages over the standard correction: (1) enveloping the true source with known confidence, (2) assuring physical source descriptions when measuring sources in fluctuating backgrounds, (3) reducing background corrected source descriptions by 1 to 8 dB for sources in steady backgrounds, and (4) providing a means to replace standardized background correction caps that incentivize against high precision grade methods.

  12. A case-control study of nasopharyngeal carcinoma among inhabitants in high background radiation areas of Yangjiang, China

    International Nuclear Information System (INIS)

    Zou Jianming; Sun Quanfu; Yuan Yongling

    1999-01-01

    Objective: The purpose of the study was to confirm and explore main risk factors of nasopharyngeal carcinoma (NPC) in cohort members of the investigated areas, and evaluate effects of confounding factors on cancer risk associated with exposure to high background radiation. Methods: The deceased cases of NPC during the period of 1987-1995 were selected as study subjects for each of whom two controls were randomly selected from potential control subjects who died from causes other than malignant tumors and external causes, and matched for sex and years of birth and death (within 5 years). Using structure questionnaire, the relevant information including socioeconomic status, dietary habits, smoking and alcohol consumption, history of illness, agricultural use of pesticide, medical X-ray exposure and familial history of NPC were collected. The odds ratio (OR) was used as a measure of association between NPC and the risk factors. Results: 102 cases and 202 controls were successfully investigated. Single factor conditional logistic regression analysis showed that the occurrence of NPC was closely positively associated with intake of salted fish, pickles, fermented soybeans, cured meats, history of chronic rhinitis and familial history of NPC. Further multiple conditional logistic regression analysis turned out that intake of salted fish, history of chronic rhinits and familial history of NPC were the independent risk factors of NPC. After controlling for history of chronic rhinits and familial history of NPC, the results based on multiple conditional logistic regression analysis from high background radiation, intake of salted fish and fermented soybeans, tobacco smoking and alcohol consumption showed that only intake of salted fish was a significant risk factor (OR = 2.8, 95% CI 1.52-5.18), tobacco smoking (OR = 1.2, 95% CI 0.65-2.22), alcohol consumption (OR = 0.83, 95% CI 0.38-1.78) and exposure to high background radiation (OR= 0.86, 95% CI 0.44-1.68) did not

  13. Pre-disposal storage, transport and handling of vitrified high level waste

    International Nuclear Information System (INIS)

    Kempe, T.F.; Martin, A.

    1981-05-01

    The objectives of the study were to review non site-specific engineering features of the storage, transport and handling of vitrified high level radioactive waste prior to its transfer into an underground repository, and to identify those features which require validation or development. Section headings are: introduction (historical and technical background); characteristics and arisings of vitrified high level waste; overpacks (additional containment barrier, corrosion resistant); interim storage of HLW; transport of HLW; handling; conclusions and recommendations. (U.K.)

  14. Sex differences in aggression among children of low and high gender inequality backgrounds: a comparison of gender role and sexual selection theories.

    Science.gov (United States)

    Nivette, Amy E; Eisner, Manuel; Malti, Tina; Ribeaud, Denis

    2014-01-01

    It is well understood in aggression research that males tend to exhibit higher levels of physical aggression than females. Yet there are still a number of gaps in our understanding of variation in sex differences in children's aggression, particularly in contexts outside North America. A key assumption of social role theory is that sex differences vary according to gender polarization, whereas sexual selection theory accords variation to the ecological environment that consequently affects male competition [Archer, J. (2009). Behavioral and Brain Sciences, 32, 249-311; Kenrick, D., & Griskevicious, V. (2009). More holes in social roles [Comment]. Behavioral and Brain Sciences, 32, 283-285]. In the present paper, we explore these contradicting theoretical frameworks by examining data from a longitudinal study of a culturally diverse sample of 863 children at ages 7-13 in Zurich, Switzerland. Making use of the large proportion of children from highly diverse immigrant background we compare the size of the sex difference in aggression between children whose parents were born in countries with low and with high levels of gender inequality. The results show that sex differences in aggression are generally larger among children with parents from high gender inequality backgrounds. However, this effect is small in comparison to the direct effect of a child's biological sex. We discuss implications for future research on sex differences in children's aggression. © 2014 Wiley Periodicals, Inc.

  15. High signal in bone marrow at diffusion-weighted imaging with body background suppression (DWIBS) in healthy children

    Energy Technology Data Exchange (ETDEWEB)

    Ording Mueller, Lil-Sofie; Avenarius, Derk [University Hospital North Norway, Department of Radiology, Tromsoe (Norway); Olsen, Oeystein E. [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom)

    2011-02-15

    In our experience, diffusion-weighted imaging with body background suppression (DWIBS) is hard to interpret in children who commonly have foci of restricted diffusion in their skeletons unrelated to pathology, sometimes in an asymmetrical pattern. This raises serious concern about the accuracy of DWIBS in cancer staging in children. To describe the signal distribution at DWIBS in the normal developing lumbar spine and pelvic skeleton. Forty-two healthy children underwent an MR DWIBS sequence of the abdomen and pelvis. An axial short-tau inversion-recovery (STIR) echo-planar imaging (EPI) pulse sequence was used. Two radiologists did a primary review of the images and based on these preliminary observations, separate scoring systems for the lumbar spine, pelvis and proximal femoral epiphyses/femoral heads were devised. Visual evaluation of the images was then performed by the two radiologists in consensus. The scoring was repeated separately 2 months later by a third radiologist. Restricted diffusion was defined as areas of high signal compared to the background. Coronal maximum intensity projection (MIP) reformats were used to assess the vertebral bodies. For the pelvis, the extension of high signal for each bone was given a score of 0 to 4. Cohen's Kappa interobserver agreement coefficients of signal distribution and asymmetry were calculated. All children had areas of high signal, both within the lumbar vertebral bodies and within the pelvic skeleton. Three patterns of signal distribution were seen in the lumbar spine, but no specific pattern was seen in the pelvis. There was a tendency toward a reduction of relative area of high signal within each bone with age, but also a widespread interindividual variation. Restricted diffusion is a normal finding in the pelvic skeleton and lumbar spine in children with an asymmetrical distribution seen in 48% of normal children in this study. DWIBS should be used with caution for cancer staging in children as this could

  16. High signal in bone marrow at diffusion-weighted imaging with body background suppression (DWIBS) in healthy children

    International Nuclear Information System (INIS)

    Ording Mueller, Lil-Sofie; Avenarius, Derk; Olsen, Oeystein E.

    2011-01-01

    In our experience, diffusion-weighted imaging with body background suppression (DWIBS) is hard to interpret in children who commonly have foci of restricted diffusion in their skeletons unrelated to pathology, sometimes in an asymmetrical pattern. This raises serious concern about the accuracy of DWIBS in cancer staging in children. To describe the signal distribution at DWIBS in the normal developing lumbar spine and pelvic skeleton. Forty-two healthy children underwent an MR DWIBS sequence of the abdomen and pelvis. An axial short-tau inversion-recovery (STIR) echo-planar imaging (EPI) pulse sequence was used. Two radiologists did a primary review of the images and based on these preliminary observations, separate scoring systems for the lumbar spine, pelvis and proximal femoral epiphyses/femoral heads were devised. Visual evaluation of the images was then performed by the two radiologists in consensus. The scoring was repeated separately 2 months later by a third radiologist. Restricted diffusion was defined as areas of high signal compared to the background. Coronal maximum intensity projection (MIP) reformats were used to assess the vertebral bodies. For the pelvis, the extension of high signal for each bone was given a score of 0 to 4. Cohen's Kappa interobserver agreement coefficients of signal distribution and asymmetry were calculated. All children had areas of high signal, both within the lumbar vertebral bodies and within the pelvic skeleton. Three patterns of signal distribution were seen in the lumbar spine, but no specific pattern was seen in the pelvis. There was a tendency toward a reduction of relative area of high signal within each bone with age, but also a widespread interindividual variation. Restricted diffusion is a normal finding in the pelvic skeleton and lumbar spine in children with an asymmetrical distribution seen in 48% of normal children in this study. DWIBS should be used with caution for cancer staging in children as this could lead

  17. High levels of serum hyaluronic acid in adults with dermatomyositis

    Directory of Open Access Journals (Sweden)

    Alana Ausciutti Victorino

    2015-04-01

    Full Text Available Background / objectives. Hyaluronic acid (HA is rarely described in dermatomyositis (DM. Thus, we determined any clinical association of serum levels of hyaluronic acid (HA in patients with dermatomyositis (DM. Materials and Methods. This cross-sectional single-center analysis 75 DM and 75 healthy individuals, during the period from January 2012 to July 2013. An anti-HA antibody assay was performed using specific ELISA/EIA kits, according to the manufacturer’s protocol. Results. The patients with DM and control subjects had comparable demographic distributions (p>0.05. The median time duration between disease diagnosis and initial symptoms was 6.0 [3.0-12.0] months, with a median DM disease duration of 4.0 [1.0-7.0] years. The median level of serum HA was significantly increased in patients with DM compared to the control group [329.0 (80.0-958.0 vs. 133.0 (30.0-262.0 ng/mL, respectively; p0.05. Serum HA also did not correlate with gender, ethnicity, auto-antibodies or drug use (p>0.05, but did correlate with cutaneous features, such as photosensitivity (p=0.001, “shawl” sign (p=0.018, “V-neck” sign (p=0.005 and cuticular hypertrophy (p=0.014. Conclusions. A high level of serum AH was observed in DM compared to healthy individuals. In DM, HA did not correlate to demographic, auto-antibodies and therapy parameters. However, HA correlated specifically with some cutaneous features, suggesting that this glycosaminoglycan could be involved in modulating cutaneous inflammation in this population. More studies are necessary to understand the correlation between AH and patients with DM.

  18. Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Javad Mortazavi

    2017-04-01

    Full Text Available Background: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. Objective: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium, Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Methods: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. Results: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6 mm; it was 14.7 (SD 0.6 mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Conclusion: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

  19. Background levels of heavy metals in surficial sediments of the Gulf of Lions (NW Mediterranean): An approach based on 133Cs normalization and lead isotope measurements

    International Nuclear Information System (INIS)

    Roussiez, Vincent; Ludwig, Wolfgang; Probst, Jean-Luc; Monaco, Andre

    2005-01-01

    This paper presents an attempt to reach natural background levels of heavy metals in surficial sediments of the Gulf of Lions (NW Mediterranean). To correct for the grain-size effect, normalization procedures based on a clay mineral indicator element are commonly used, after a first grain size separation by sieving. In our study, we tested the applicability of this method with respect to commonly used normalizer elements, and found that stable Cs shows the best ability to reflect the fine sediment fraction. Background levels were successfully reached for Co, Cr, Cu, Ni and Pb, compared to various literature references. Nevertheless, in the case of lead, the normalized data depicted a general enrichment in all samples, and the natural levels could only be reached when concentrations were corrected for the atmospheric contribution by analysing lead isotope ratios. Also for Zn, a general enrichment was found in our samples, although less important. - Among several potential normalizers, stable Cs ( 133 Cs) depicted the best ability to correct for the grain-size effect of shelf sediments and was used to estimate regional background levels of heavy metals

  20. An introductory overview of the epidemiological study on the population at the high background radiation areas in Yangjiang, China

    Energy Technology Data Exchange (ETDEWEB)

    Wei Luxin [Ministry of Health, Beijing (China). Lab. of Industrial Hygiene; Sugahara, Tsutomu

    2000-10-01

    The epidemiological study on the residents of the high background radiation areas in Yangjiang, China was started by Chinese scientists in 1972 and continued until 1986. In 1991, Japanese scientists recognized the importance of the work and a joint feasibility study was conducted with revised protocols. The feasibility study matured to a cooperative project involving both Chinese and Japanese scientists in 1992, which currently is still in progress. The project was divide into three phases; the first being from 1992 to 1995, the second from 1995-1998 and the third from 1998 to 2001. The results of the first phase were reported previously in 1996. The present paper is a historical overview of the studies before the cooperation and the first two phases. Remarks are made on the detailed data on dosimetry, cytogenetic studies and cancer epidemiology of a series of the papers in this supplemental issue. Some problems such as paradoxical observations between cytogenetic results and cancer mortality, and the importance of the high background study in risk assessment are discussed. (author)

  1. An introductory overview of the epidemiological study on the population at the high background radiation areas in Yangjiang, China

    International Nuclear Information System (INIS)

    Wei Luxin; Sugahara, Tsutomu

    2000-01-01

    The epidemiological study on the residents of the high background radiation areas in Yangjiang, China was started by Chinese scientists in 1972 and continued until 1986. In 1991, Japanese scientists recognized the importance of the work and a joint feasibility study was conducted with revised protocols. The feasibility study matured to a cooperative project involving both Chinese and Japanese scientists in 1992, which currently is still in progress. The project was divide into three phases; the first being from 1992 to 1995, the second from 1995-1998 and the third from 1998 to 2001. The results of the first phase were reported previously in 1996. The present paper is a historical overview of the studies before the cooperation and the first two phases. Remarks are made on the detailed data on dosimetry, cytogenetic studies and cancer epidemiology of a series of the papers in this supplemental issue. Some problems such as paradoxical observations between cytogenetic results and cancer mortality, and the importance of the high background study in risk assessment are discussed. (author)

  2. The thickness design of unintentionally doped GaN interlayer matched with background doping level for InGaN-based laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P.; Zhao, D. G., E-mail: dgzhao@red.semi.ac.cn; Jiang, D. S.; Zhu, J. J.; Liu, Z. S.; Yang, J.; Li, X.; Le, L. C.; He, X. G.; Liu, W.; Li, X. J.; Liang, F. [State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Zhang, B. S.; Yang, H. [Key Laboratory of Nano-devices and Applications of CAS, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Zhang, Y. T.; Du, G. T. [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130023 (China)

    2016-03-15

    In order to reduce the internal optical loss of InGaN laser diodes, an unintentionally doped GaN (u-GaN) interlayer is inserted between InGaN/GaN multiple quantum well active region and Al{sub 0.2}Ga{sub 0.8}N electron blocking layer. The thickness design of u-GaN interlayer matching up with background doping level for improving laser performance is studied. It is found that a suitably chosen u-GaN interlayer can well modulate the optical absorption loss and optical confinement factor. However, if the value of background doping concentration of u-GaN interlayer is too large, the output light power may decrease. The analysis of energy band diagram of a LD structure with 100 nm u-GaN interlayer shows that the width of n-side depletion region decreases when the background concentration increases, and may become even too small to cover whole MQW, resulting in a serious decrease of the output light power. It means that a suitable interlayer thickness design matching with the background doping level of u-GaN interlayer is significant for InGaN-based laser diodes.

  3. The thickness design of unintentionally doped GaN interlayer matched with background doping level for InGaN-based laser diodes

    Directory of Open Access Journals (Sweden)

    P. Chen

    2016-03-01

    Full Text Available In order to reduce the internal optical loss of InGaN laser diodes, an unintentionally doped GaN (u-GaN interlayer is inserted between InGaN/GaN multiple quantum well active region and Al0.2Ga0.8N electron blocking layer. The thickness design of u-GaN interlayer matching up with background doping level for improving laser performance is studied. It is found that a suitably chosen u-GaN interlayer can well modulate the optical absorption loss and optical confinement factor. However, if the value of background doping concentration of u-GaN interlayer is too large, the output light power may decrease. The analysis of energy band diagram of a LD structure with 100 nm u-GaN interlayer shows that the width of n-side depletion region decreases when the background concentration increases, and may become even too small to cover whole MQW, resulting in a serious decrease of the output light power. It means that a suitable interlayer thickness design matching with the background doping level of u-GaN interlayer is significant for InGaN-based laser diodes.

  4. 'Ogura'-based 'CMS' lines with different nuclear backgrounds of cabbage revealed substantial diversity at morphological and molecular levels.

    Science.gov (United States)

    Parkash, Chander; Kumar, Sandeep; Singh, Rajender; Kumar, Ajay; Kumar, Satish; Dey, Shyam Sundar; Bhatia, Reeta; Kumar, Raj

    2018-01-01

    A comprehensive study on characterization and genetic diversity analysis was carried out in 16 'Ogura'-based 'CMS' lines of cabbage using 14 agro-morphological traits and 29 SSR markers. Agro-morphological characterization depicted considerable variations for different horticultural traits studied. The genotype, ZHA-2, performed better for most of the economically important quantitative traits. Further, gross head weight (0.76), head length (0.60) and head width (0.83) revealed significant positive correlation with net head weight. Dendrogram based on 10 quantitative traits exhibited considerable diversity among different CMS lines and principle component analysis (PCA) indicated that net and gross head weight, and head length and width are the main components of divergence between 16 CMS lines of cabbage. In molecular study, a total of 58 alleles were amplified by 29 SSR primers, averaging to 2.0 alleles in each locus. High mean values of Shannon's Information index (0.62), expected (0.45) and observed (0.32) heterozygosity and polymorphic information content (0.35) depicted substantial polymorphism. Dendrogram based on Jaccard's similarity coefficient constructed two major groups and eight sub-groups, which revealed substantial diversity among different CMS lines. In overall, based on agro-morphological and molecular studies genotype RRMA, ZHA-2 and RCA were found most divergent. Hence, they have immense potential in future breeding programs for the high-yielding hybrid development in cabbage.

  5. Study of cancer mortality among inhabitants in the high background radiation area of Yangjiang, China (1979-1998)

    International Nuclear Information System (INIS)

    Tao Zufan; Sun Quanfu; Li Jia; Liu Yusheng; Wei Lvxin; Zou Jianming; Zha Yongru; Yuan Yongling

    2004-01-01

    Objective: The objective of the study is to explore cancer risk associated with the low-level radiation exposure of average annual effective dose of 6.4 mSv occurring in the high background radiation area (HBRA) in Yangjiang of Guangdong Province, China. Methods: The data of cancer mortality for period of 1979-1986 were collected in prospective follow-up survey of dynamic populations and those of 1987-1998 were obtained from a fixed cohort in the same method. Record linkage was used to combine the two data sets. The external dose received by the inhabitants was estimated on the basis of hamlet-specific environmental doses and sex-age-specific occupancy factors, and the fixed values of internal dose regardless of sex and age was assumed. Relative risk (RR) and excess relative risk coefficient (ERR/Sv) and their 95% confidence interval (CI) were calculated using the AMFIT in Epicure. Results: During the period of 1979-1998, the follow-up for 125 079 subjects accumulated 1 992 940 person-years and identified 12 444 deaths, including 1202 cancer deaths. The RR of mortality of all cancers in whole HBRA was 1.00 (95% CI, 0.89-1.14) showing no statistical difference between the HBRA and the control area (CA). The RRs of all cancers in low, intermediate and high dose groups in the HBRA did not show statistical difference from the control group, either. The region (Yangdong and Yangxi) and the follow-up period(1979-1986 and 1987-1998) did not evidently modify the results, and the restriction of cancer cases to those with pathology information made no statistically significant change in RRs. In site-specific cancer analysis, only the RR of esophageal cancer showed statistical excess in the HBRA, the others did not show statistical difference between the HBRA and the CA. The comparison of RRs of site-specific cancer mortality among different dose groups and the dose-response analysis of site-specific cancer mortality related to cumulative individual lifetime dose did not give

  6. Hanford high-level waste melter system evaluation data packages

    International Nuclear Information System (INIS)

    Elliott, M.L.; Shafer, P.J.; Lamar, D.A.; Merrill, R.A.; Grunewald, W.; Roth, G.; Tobie, W.

    1996-03-01

    The Tank Waste Remediation System is selecting a reference melter system for the Hanford High-Level Waste vitrification plant. A melter evaluation was conducted in FY 1994 to narrow down the long list of potential melter technologies to a few for testing. A formal evaluation was performed by a Melter Selection Working Group (MSWG), which met in June and August 1994. At the June meeting, MSWG evaluated 15 technologies and selected six for more thorough evaluation at the Aug. meeting. All 6 were variations of joule-heated or induction-heated melters. Between the June and August meetings, Hanford site staff and consultants compiled data packages for each of the six melter technologies as well as variants of the baseline technologies. Information was solicited from melter candidate vendors to supplement existing information. This document contains the data packages compiled to provide background information to MSWG in support of the evaluation of the six technologies. (A separate evaluation was performed by Fluor Daniel, Inc. to identify balance of plant impacts if a given melter system was selected.)

  7. The Software Architecture of the LHCb High Level Trigger

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The LHCb experiment is a spectrometer dedicated to the study of heavy flavor at the LHC. The rate of proton-proton collisions at the LHC is 15 MHz, but disk space limitations mean that only 3 kHz can be written to tape for offline processing. For this reason the LHCb data acquisition system -- trigger -- plays a key role in selecting signal events and rejecting background. In contrast to previous experiments at hadron colliders like for example CDF or D0, the bulk of the LHCb trigger is implemented in software and deployed on a farm of 20k parallel processing nodes. This system, called the High Level Trigger (HLT) is responsible for reducing the rate from the maximum at which the detector can be read out, 1.1 MHz, to the 3 kHz which can be processed offline,and has 20 ms in which to process and accept/reject each event. In order to minimize systematic uncertainties, the HLT was designed from the outset to reuse the offline reconstruction and selection code, and is based around multiple independent and redunda...

  8. A High-Voltage Level Tolerant Transistor Circuit

    NARCIS (Netherlands)

    Annema, Anne J.; Geelen, Godefridus Johannes Gertrudis Maria

    2001-01-01

    A high-voltage level tolerant transistor circuit, comprising a plurality of cascoded transistors, including a first transistor (T1) operatively connected to a high-voltage level node (3) and a second transistor (T2) operatively connected to a low-voltage level node (2). The first transistor (T1)

  9. 40 CFR 227.30 - High-level radioactive waste.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false High-level radioactive waste. 227.30...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from the operation of the first cycle solvent extraction system, or equivalent, and the concentrated waste from...

  10. Extract of mangosteen increases high density lipoprotein levels in rats fed high lipid

    Directory of Open Access Journals (Sweden)

    Dwi Laksono Adiputro

    2013-04-01

    Full Text Available Background In cardiovascular medicine, Garcinia mangostana has been used as an antioxidant to inhibit oxidation of low density lipoproteins and as an antiobesity agent. The effect of Garcinia mangostana on hyperlipidemia is unknown. The aim of this study was to evaluate the effect of an ethanolic extract of Garcinia mangostana pericarp on lipid profile in rats fed a high lipid diet. Methods A total of 40 rats were divided into five groups control, high lipid diet, and high lipid diet + ethanolic extract of Garcinia mangostana pericarp at dosages of 200, 400, and 800 mg/kg body weight. The control group received a standard diet for 60 days. The high lipid diet group received standard diet plus egg yolk, goat fat, cholic acid, and pig fat for 60 days with or without ethanolic extract of Garcinia mangostana pericarp by the oral route. After 60 days, rats were anesthesized with ether for collection of blood by cardiac puncture. Analysis of blood lipid profile comprised colorimetric determination of cholesterol, triglyceride, low density lipoprotein (LDL, and high density lipoprotein (HDL. Results From the results of one-way ANOVA it was concluded that there were significant between-group differences in cholesterol, trygliceride, LDL, and HDL levels (p=0.000. Ethanolic extract of Garcinia mangostana pericarp significantly decreased cholesterol, trygliceride, and LDL levels, starting at 400 mg/kg body weight (p=0.000. Ethanolic extract of Garcinia mangostana pericarp significantly increased HDL level starting at 200 mg/kg body weight (p=0.000. Conclusion Ethanolic extract of Garcinia mangostana pericarp has a beneficial effect on lipid profile in rats on a high lipid diet.

  11. Extract of mangosteen increases high density lipoprotein levels in rats fed high lipid

    Directory of Open Access Journals (Sweden)

    Dwi Laksono Adiputro

    2015-12-01

    Full Text Available BACKGROUND In cardiovascular medicine, Garcinia mangostana has been used as an antioxidant to inhibit oxidation of low density lipoproteins and as an antiobesity agent. The effect of Garcinia mangostana on hyperlipidemia is unknown. The aim of this study was to evaluate the effect of an ethanolic extract of Garcinia mangostana pericarp on lipid profile in rats fed a high lipid diet. METHODS A total of 40 rats were divided into five groups control, high lipid diet, and high lipid diet + ethanolic extract of Garcinia mangostana pericarp at dosages of 200, 400, and 800 mg/kg body weight. The control group received a standard diet for 60 days. The high lipid diet group received standard diet plus egg yolk, goat fat, cholic acid, and pig fat for 60 days with or without ethanolic extract of Garcinia mangostana pericarp by the oral route. After 60 days, rats were anesthesized with ether for collection of blood by cardiac puncture. Analysis of blood lipid profile comprised colorimetric determination of cholesterol, triglyceride, low density lipoprotein (LDL, and high density lipoprotein (HDL. RESULTS From the results of one-way ANOVA it was concluded that there were significant between-group differences in cholesterol, trygliceride, LDL, and HDL levels (p=0.000. Ethanolic extract of Garcinia mangostana pericarp significantly decreased cholesterol, trygliceride, and LDL levels, starting at 400 mg/kg body weight (p=0.000. Ethanolic extract of Garcinia mangostana pericarp significantly increased HDL level starting at 200 mg/kg body weight (p=0.000. CONCLUSION Ethanolic extract of Garcinia mangostana pericarp has a beneficial effect on lipid profile in rats on a high lipid diet.

  12. Variations in voice level and fundamental frequency with changing background noise level and talker-to-listener distance while wearing hearing protectors: A pilot study

    DEFF Research Database (Denmark)

    Bouserhal, Rachel E.; MacDonald, Ewen; Falk, Tiago H.

    2016-01-01

    in voice level and fundamental frequency in noise and with varying talker-to-listener distance. Study sample: Twelve participants with a mean age of 28 participated in this study. Results: Compared to existing data, results show a trend similar to the open ear condition with the exception of the occluded...

  13. Background Material

    DEFF Research Database (Denmark)

    Zandersen, Marianne; Hyytiäinen, Kari; Saraiva, Sofia

    This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders.......This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders....

  14. A low-background piston-cylinder-type hybrid high pressure cell for muon-spin rotation/relaxation experiments

    Science.gov (United States)

    Shermadini, Z.; Khasanov, R.; Elender, M.; Simutis, G.; Guguchia, Z.; Kamenev, K. V.; Amato, A.

    2017-10-01

    A low background double-wall piston-cylinder-type pressure cell is developed at the Paul Scherrer Institute. The cell is made from BERYLCO-25 (beryllium copper) and MP35N nonmagnetic alloys with the design and dimensions which are specifically adapted to muon-spin rotation/relaxation (μSR) measurements. The mechanical design and performance of the pressure cell are evaluated using finite-element analysis (FEA). By including the measured stress-strain characteristics of the materials into the finite-element model, the cell dimensions are optimized with the aim to reach the highest possible pressure while maintaining the sample space large (6 mm in diameter and 12 mm high). The presented unconventional design of the double-wall piston-cylinder pressure cell with a harder outer MP35N sleeve and a softer inner CuBe cylinder enables pressures of up to 2.6 GPa to be reached at ambient temperature, corresponding to 2.2 GPa at low temperatures without any irreversible damage to the pressure cell. The nature of the muon stopping distribution, mainly in the sample and in the CuBe cylinder, results in a low-background μSR signal.

  15. High Frequency Propagation modeling in a disturbed background ionosphere: Results from the Metal Oxide Space Cloud (MOSC) experiment

    Science.gov (United States)

    Joshi, D. R.; Groves, K. M.

    2015-12-01

    The Air Force Research Laboratory (AFRL) launched two sounding rockets in the Kwajalein Atoll, Marshall Islands, in May 2013 known as the Metal Oxide Space Cloud (MOSC) experiment to study the interactions of artificial ionization and the background plasma. The rockets released samarium metal vapor in the lower F-region of the ionosphere that ionized forming a plasma cloud. A host of diagnostic instruments were used to probe and characterize the cloud including the ALTAIR incoherent scatter radar, multiple GPS and optical instruments, satellite radio beacons, and a dedicated network of high frequency (HF) radio links. Data from ALTAIR incoherent scatter radar and HF radio links have been analyzed to understand the impacts of the artificial ionization on radio wave propagation. During the first release the ionosphere was disturbed, rising rapidly and spread F formed within minutes after the release. To address the disturbed conditions present during the first release, we have developed a new method of assimilating oblique ionosonde data to generate the background ionosphere that can have numerous applications for HF systems. The link budget analysis of the received signals from the HF transmitters explains the missing low frequencies in the received signals along the great circle path. Observations and modeling confirm that the small amounts of ionized material injected in the lower-F region resulted in significant changes to the natural propagation environment.

  16. Use of isotopic signature of radionuclides released from uranium mines and mills to discriminate low levels of environmental impact against natural background levels

    International Nuclear Information System (INIS)

    Zettwoog, P.; Lemaitre, N.; Bernhard, S.; Vauzelle, Y.

    1997-01-01

    In France, uranium ores have been exploited in rural areas with a low population density. The critical population group which is identified for radiological impact studies lives close to the uranium facilities, at distances from a few hundred metres to 1 kilometer. Within this range, the radioactivity of the environment is still detectable amongst the natural background. Mining companies manage surveillance networks according to strict specifications laid down by the government authorities. For active mining operations it is the exposure to daughter products of radon 222 that forms the bulk of the total effective dose. After closure of a mine and rehabilitation of the site, products such as uranium 238 and radium 226 in the water can become the major components of the total effective dose. Surveillance networks are built to allow direct measurement of the radon daughter products critical to the alpha energy and measurements of the water activities for uranium 238 and radium 226. Annual limits for the effective individual doses are given and determined by the authorities. The industry must manage effective annual doses of the order of 1 mSv. The natural exposure which is not part of the regulation is of the same order (1 mSv) as the exposure created by the industry. The results given are therefore lacking in clarity for the public. The Office de Protection contre les Rayonnements Ionisants (OPRI) and ALGADE are developing methods which allow differentiation between natural phenomena and man-made phenomena. It has been recognised that for a region where mining activities have taken place, the isotopic signature of uranium, radium and radon can clearly be recognised from the same product of natural origin. In the case of radon, for example, the industry produces only radon 222 while natural emanations are composed of radon 220 and radon 222. (author)

  17. Background Checks for all Gun Buyers and Gun Violence Restraining Orders: State Efforts to Keep Guns from High-Risk Persons.

    Science.gov (United States)

    Vernick, Jon S; Alcorn, Ted; Horwitz, Joshua

    2017-03-01

    There were more than 36,000 firearm-related deaths in the U.S. in 2015. Under federal law, a background check is required only for gun purchases from licensed dealers. Research suggests that some persons prohibited from owning a gun turn to private sellers, including those identified online, to attempt to obtain a firearm. State-level approaches to make it more difficult for high-risk persons to purchase or possess firearms include universal background check (UBC) and gun violence restraining order (GVRO) laws. UBC laws, on the books in 18 states as of the end of 2016, can reduce both homicide and suicide rates. After Colorado adopted a UBC law in 2013, the number of background checks conducted by private sellers for sales occurring at places other than gun shows steadily increased. GVRO laws give law enforcement and families the authority to petition a court to temporarily remove firearms from an individual who presents a danger to himself or others during times of crisis, regardless of whether that person has been diagnosed with a mental illness. California enacted a GVRO law in 2014. Data are emerging to suggest the effectiveness of GVRO-type laws at averting suicides and providing an entryway to services.

  18. Excess relative risk of solid cancer mortality after prolonged exposure to naturally occurring high background radiation in Yangjiang, China

    Energy Technology Data Exchange (ETDEWEB)

    Sun Quanfu; Tao Zufan [Ministry of Health, Beijing (China). Lab. of Industrial Hygiene; Akiba, Suminori (and others)

    2000-10-01

    A study was made on cancer mortality in the high-background radiation areas of Yangjiang, China. Based on hamlet-specific environmental doses and sex- and age-specific occupancy factors, cumulative doses were calculated for each subject. In this article, we describe how the indirect estimation was made on individual dose and the methodology used to estimate radiation risk. Then, assuming a linear dose response relationship and using cancer mortality data for the period 1979-1995, we estimate the excess relative risk per Sievert for solid cancer to be -0.11 (95% CI, -0.67, 0.69). Also, we estimate the excess relative risks of four leading cancers in the study areas, i.e., cancers of the liver, nasopharynx, lung and stomach. In addition, we evaluate the effects of possible bias on our risk estimation. (author)

  19. Estimation of thorium intake due to consumption of vegetables by inhabitants of high background radiation area by INAA

    International Nuclear Information System (INIS)

    Sathyapriya, R.S.; Suma Nair; Prabhath, R.K.; Madhu Nair; Rao, D.D.

    2012-01-01

    A study was conducted to estimate the thorium concentration in locally grown vegetables in high background radiation area (HBRA) of southern coastal regions of India. Locally grown vegetables were collected from HBRA of southern coastal regions of India. Thorium concentration was quantified using instrumental neutron activation analysis. The samples were irradiated at CIRUS reactor and counted using a 40% relative efficiency HPGe detector coupled to MCA. The annual intake of thorium was evaluated using the consumption data provided by National Nutrition Monitoring Board. The daily intake of 232 Th from the four food categories (green leafy vegetables, others vegetables, roots and tubers, and fruits) ranged between 0.27 and 5.352 mBq d -1 . The annual internal dose due to ingestion of thorium from these food categories was 46.8 x 10 -8 for female and 58.6 x 10 -8 Sv y -1 for male. (author)

  20. Determination of organically bound tritium background level in biological samples from a wide area in the south-west of France

    International Nuclear Information System (INIS)

    Pointurier, F.; Baglan, N.; Alanic, G.; Chiappini, R.

    2003-01-01

    In this paper, the authors describe a sensitive method for low-level non-exchangeable OBT determination. This methodology combines suitable sample treatment, a combustion apparatus for large-sized samples and low-background liquid scintillation spectrometry, along with precautions that substantially reduce the risks of sample contamination. Great care must be taken in the measurement of non-exchangeable OBT at environmental levels. Many authors have discussed the opportunities for cross-contamination between samples and contamination by exchange with the laboratory atmosphere. The authors also describe an application of the methodology to a large-scale sampling and measurement campaign, aimed at the determination of the environmental non-exchangeable OBT background level in tree leaves and ferns collected on the site and in the vicinity of a research centre located in the south-west of France, not far from Bordeaux. This study constitutes a 'zero level' for the non-exchangeable OBT activity, as, to our knowledge, there is no tritium source within or in the surroundings of the sampled area capable of producing non-exchangeable OBT activities above the natural levels. Our analyses showed that non-exchangeable OBT activities in the collected samples were very low, ranging from below the detection limit (ca 0.7 Bq kg -1 of dry material) to ca 2 Bq kg -1 of dry material. These values are similar to the natural tritium background measured in water samples. No discrepancies can be shown between fern samples and oak tree leaf samples or between samples collected inside and outside the research site

  1. Determination of organically bound tritium background level in biological samples from a wide area in the south-west of France

    Energy Technology Data Exchange (ETDEWEB)

    Pointurier, F. E-mail: fabien.pointurier@cea.fr; Baglan, N.; Alanic, G.; Chiappini, R

    2003-07-01

    In this paper, the authors describe a sensitive method for low-level non-exchangeable OBT determination. This methodology combines suitable sample treatment, a combustion apparatus for large-sized samples and low-background liquid scintillation spectrometry, along with precautions that substantially reduce the risks of sample contamination. Great care must be taken in the measurement of non-exchangeable OBT at environmental levels. Many authors have discussed the opportunities for cross-contamination between samples and contamination by exchange with the laboratory atmosphere. The authors also describe an application of the methodology to a large-scale sampling and measurement campaign, aimed at the determination of the environmental non-exchangeable OBT background level in tree leaves and ferns collected on the site and in the vicinity of a research centre located in the south-west of France, not far from Bordeaux. This study constitutes a 'zero level' for the non-exchangeable OBT activity, as, to our knowledge, there is no tritium source within or in the surroundings of the sampled area capable of producing non-exchangeable OBT activities above the natural levels. Our analyses showed that non-exchangeable OBT activities in the collected samples were very low, ranging from below the detection limit (ca 0.7 Bq kg{sup -1} of dry material) to ca 2 Bq kg{sup -1} of dry material. These values are similar to the natural tritium background measured in water samples. No discrepancies can be shown between fern samples and oak tree leaf samples or between samples collected inside and outside the research site.

  2. Evaluation of radionuclide concentrations in high-level radioactive wastes

    International Nuclear Information System (INIS)

    Fehringer, D.J.

    1985-10-01

    This report describes a possible approach for development of a numerical definition of the term ''high-level radioactive waste.'' Five wastes are identified which are recognized as being high-level wastes under current, non-numerical definitions. The constituents of these wastes are examined and the most hazardous component radionuclides are identified. This report suggests that other wastes with similar concentrations of these radionuclides could also be defined as high-level wastes. 15 refs., 9 figs., 4 tabs

  3. The flip-over effect in pulsed laser deposition: Is it relevant at high background gas pressures?

    International Nuclear Information System (INIS)

    Ojeda-G-P, Alejandro; Schneider, Christof W.; Döbeli, Max; Lippert, Thomas; Wokaun, Alexander

    2015-01-01

    Highlights: • The flip-over effect in PLD is observed up to high deposition pressures. • Consistent congruent transfer of the target composition is generally not correct. • The choice of deposition pressure can change the film composition strongly. • Large compositional changes appear at high off-axis angles and large spot sizes. - Abstract: In pulsed laser deposition the use of a rectangular or elliptical beam spot with a non 1:1 aspect ratio leads to the so called flip-over effect. Here, the longest dimension of the laser spot results in the shortest direction of plasma plume expansion. This effect has been mainly reported for vacuum depositions of single element targets and is particularly noticeable when the aspect ratio of the beam spot is large. We investigate the flip-over effect in vacuum and at three relevant background-gas pressures for pulsed laser deposition using a La 0.4 Ca 0.6 MnO 3 target by measuring the thickness dependence of the deposited material as a function of angle. The film thicknesses and compositions are determined by Rutherford backscattering and argon is used to reduce the influence of additional chemical reactions in the plasma. The results show the prevalence of the flip-over effect for all pressures except for the highest, i.e. 1 × 10 −1 mbar, where the film thickness is constant for all angles. The composition profiles show noticeable compositional variations of up to 30% with respect to the target material depending on the background gas pressure, the angular location, and the laser spot dimensions.

  4. The flip-over effect in pulsed laser deposition: Is it relevant at high background gas pressures?

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda-G-P, Alejandro [Paul Scherrer Institut, General Energy Research Department, 5232 Villigen-PSI (Switzerland); Schneider, Christof W., E-mail: christof.schneider@psi.ch [Paul Scherrer Institut, General Energy Research Department, 5232 Villigen-PSI (Switzerland); Döbeli, Max [Ion Beam Physics, ETH Zurich, CH-8093 Zurich (Switzerland); Lippert, Thomas; Wokaun, Alexander [Paul Scherrer Institut, General Energy Research Department, 5232 Villigen-PSI (Switzerland)

    2015-12-01

    Highlights: • The flip-over effect in PLD is observed up to high deposition pressures. • Consistent congruent transfer of the target composition is generally not correct. • The choice of deposition pressure can change the film composition strongly. • Large compositional changes appear at high off-axis angles and large spot sizes. - Abstract: In pulsed laser deposition the use of a rectangular or elliptical beam spot with a non 1:1 aspect ratio leads to the so called flip-over effect. Here, the longest dimension of the laser spot results in the shortest direction of plasma plume expansion. This effect has been mainly reported for vacuum depositions of single element targets and is particularly noticeable when the aspect ratio of the beam spot is large. We investigate the flip-over effect in vacuum and at three relevant background-gas pressures for pulsed laser deposition using a La{sub 0.4}Ca{sub 0.6}MnO{sub 3} target by measuring the thickness dependence of the deposited material as a function of angle. The film thicknesses and compositions are determined by Rutherford backscattering and argon is used to reduce the influence of additional chemical reactions in the plasma. The results show the prevalence of the flip-over effect for all pressures except for the highest, i.e. 1 × 10{sup −1} mbar, where the film thickness is constant for all angles. The composition profiles show noticeable compositional variations of up to 30% with respect to the target material depending on the background gas pressure, the angular location, and the laser spot dimensions.

  5. Analysis of Cyberbullying Sensitivity Levels of High School Students and Their Perceived Social Support Levels

    Science.gov (United States)

    Akturk, Ahmet Oguz

    2015-01-01

    Purpose: The purpose of this paper is to determine the cyberbullying sensitivity levels of high school students and their perceived social supports levels, and analyze the variables that predict cyberbullying sensitivity. In addition, whether cyberbullying sensitivity levels and social support levels differed according to gender was also…

  6. Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran

    International Nuclear Information System (INIS)

    Bavarnegin, E.; Fathabadi, N.; Vahabi Moghaddam, M.; Vasheghani Farahani, M.; Moradi, M.; Babakhni, A.

    2013-01-01

    Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m −2 h −1 . The 226 Ra, 232 Th and 40 K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of 226 Ra, 232 Th and 40 K content varied from below the minimum detection limit up to 86,400 Bq kg −1 , 187 Bq kg −1 and 1350 Bq kg −1 , respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. -- Highlights: ► In the selection process of local samples, portable scintillometer (NaI) was used. ► The activity concentration of 226 Ra varied from below the MDL up to 86400 Bq kg −1 . ► The activity concentration of 232 Th varied from below the MDL up to 187 Bq kg −1 . ► The activity concentration of 40 K varied from below the MDL up to 1350 Bq kg −1

  7. Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran.

    Science.gov (United States)

    Bavarnegin, E; Fathabadi, N; Vahabi Moghaddam, M; Vasheghani Farahani, M; Moradi, M; Babakhni, A

    2013-03-01

    Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m(-2) h(-1). The (226)Ra, (232)Th and (40)K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of (226)Ra, (232)Th and (40)K content varied from below the minimum detection limit up to 86,400 Bq kg(-1), 187 Bq kg(-1) and 1350 Bq kg(-1), respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Study of radiation background at various high altitude locations in preparation for rare event search in cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, R.; Dey, S.; Ghosh, Sanjay K.; Maulik, A.; Raha, Sibaji; Syam, D., E-mail: rupamoy@gmail.com, E-mail: dey_s2001@yahoo.com, E-mail: sanjay@jcbose.ac.in, E-mail: atanu.maulik@jcbose.ac.in, E-mail: sibaji.raha@jcbose.ac.in, E-mail: syam.debapriyo@gmail.com [Centre for Astroparticle Physics and Space Science, Bose Institute, Block-EN, Sector-V, Kolkata-700091 (India)

    2017-04-01

    Various phenomenological models presented over the years have hinted at the possible presence of strangelets, which are nuggets of Strange Quark Matter (SQM), in cosmic rays. One way to search for such rare events is through the deployment of large area Nuclear Track Detector (NTD) arrays at high mountain altitudes. Before the deployment of any such array can begin, a detailed study of the radiation background is essential. Also, a proper understanding of the response of detectors exposed to extreme weather conditions is necessary. With that aim, pilot studies were carried out at various high altitude locations in India such as Darjeeling (2200 m a.m.s.l), Ooty (2200 m a.m.s.l) and Hanle (4500 m a.m.s.l). Small arrays of CR-39 as well as high threshold Polyethylene Terephthalate (PET) detectors were given open air exposures for periods ranging from three months to two years. The findings of such studies are reported in this paper.

  9. Connectionist Models and Parallelism in High Level Vision.

    Science.gov (United States)

    1985-01-01

    GRANT NUMBER(s) Jerome A. Feldman N00014-82-K-0193 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENt. PROJECT, TASK Computer Science...Connectionist Models 2.1 Background and Overviev % Computer science is just beginning to look seriously at parallel computation : it may turn out that...the chair. The program includes intermediate level networks that compute more complex joints and ones that compute parallelograms in the image. These

  10. Local level epidemiological analysis of TB in people from a high incidence country of birth

    OpenAIRE

    Massey Peter D; Durrheim David N; Stephens Nicola; Christensen Amanda

    2013-01-01

    Abstract Background The setting for this analysis is the low tuberculosis (TB) incidence state of New South Wales (NSW), Australia. Local level analysis of TB epidemiology in people from high incidence countries-of-birth (HIC) in a low incidence setting has not been conducted in Australia and has not been widely reported. Local level analysis could inform measures such as active case finding and targeted earlier diagnosis. The aim of this study was to use a novel approach to identify local ar...

  11. Capacitance–voltage and current–voltage characteristics for the study of high background doping and conduction mechanisms in GaAsN grown by chemical beam epitaxy

    International Nuclear Information System (INIS)

    Bouzazi, Boussairi; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi

    2013-01-01

    Highlights: ► The cause of high background doping was confirmed and characterized. ► The current–voltage characteristics deviate from the thermionic emission. ► The recombination current is attributed to a hole trap (E V + 0.52 eV). ► The hole trap (E V + 0.52 eV) was confirmed by DLTS measurements. -- Abstract: The temperature dependence of capacitance–voltage (C–V) and current voltage (I–V) characteristics were used to study the cause of high background doping and the underlying current transport mechanisms in GaAsN Schottky diode grown by chemical beam epitaxy (CBE). In one hand, a nitrogen-related sigmoid increase of junction capacitance and ionized acceptor concentration was observed in the temperature range 70–100 K and was attributed to the thermal ionization of a nitrogen–hydrogen-related deep acceptor-state, with thermal activation energy of approximately 0.11 eV above the valence band maximum (VBM) of GaAsN. This acceptor state is mainly responsible for the high background doping in unintentionally doped GaAsN grown by CBE. On the other hand, the I–V characteristics at different temperatures were found to deviate from the well known pure thermionic-emission mechanism. Based on their fitting at each temperature, the recombination current in the space charge region of GaAsN Schottky diode was mainly attributed to a hole trap, localized at 0.51 eV above the VBM. Given the accuracy of measurements, this result was confirmed by deep level transient spectroscopy measurements. Nevertheless, considering the Shockley–Read–Hall model of generation-recombination, the recombination activity of this defect was quantified and qualified to be weak compared with the markedly degradation of minority carrier lifetime in GaAsN material

  12. High rate of virologic suppression with darunavir/ritonavir plus optimized background therapy among highly antiretroviral-experienced HIV-infected patients: results of a prospective cohort study in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    José Ernesto Vidal

    Full Text Available OBJECTIVES: To assess the virologic and immunological response of darunavir/ritonavir plus optimized background therapy in highly antiretroviral-experienced HIV-infected patients in Brazil. METHODS: Prospective cohort study carried out in a tertiary center in Sao Paulo, Brazil. Three-class antiretroviral-experienced patients with confirmed virologic failure began darunavir/ritonavir plus optimized background therapy (nucleoside/tide reverse transcriptase inhibitors ± raltegravir ± enfuvirtide ± maraviroc after performing a genotypic resistance assay. Clinical evaluation and laboratory tests were collected at baseline and at weeks 12, 24, and 48. Multivariate analysis was performed to identify predictors of virologic response at 48 weeks. RESULTS: Ninety-two patients were included. The median of darunavir resistant mutation was 1 (range 0-6. The median genotypic sensitivity score in the optimized background therapy was 2 (interquartile range 1-2. At week 48, 83% (95% CI: 75-90% had an HIV RNA level 100 000 copies/mL was inversely associated with virologic success at week 48 (HR: 0.22, 95% CI: 0.06-0.85, p = 0.028. CONCLUSIONS: Darunavir/ritonavir plus optimized background therapy was a highly effective salvage regimen under clinical routine conditions in a referral center in Brazil, which is similar to the reported in high-income countries.

  13. High rate of virologic suppression with darunavir/ritonavir plus optimized background therapy among highly antiretroviral-experienced HIV-infected patients: results of a prospective cohort study in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    José Ernesto Vidal

    2013-02-01

    Full Text Available OBJECTIVES: To assess the virologic and immunological response of darunavir/ritonavir plus optimized background therapy in highly antiretroviral-experienced HIV-infected patients in Brazil. METHODS: Prospective cohort study carried out in a tertiary center in Sao Paulo, Brazil. Three-class antiretroviral-experienced patients with confirmed virologic failure began darunavir/ritonavir plus optimized background therapy (nucleoside/tide reverse transcriptase inhibitors ± raltegravir ± enfuvirtide ± maraviroc after performing a genotypic resistance assay. Clinical evaluation and laboratory tests were collected at baseline and at weeks 12, 24, and 48. Multivariate analysis was performed to identify predictors of virologic response at 48 weeks. RESULTS: Ninety-two patients were included. The median of darunavir resistant mutation was 1 (range 0-6. The median genotypic sensitivity score in the optimized background therapy was 2 (interquartile range 1-2. At week 48, 83% (95% CI: 75-90% had an HIV RNA level 100 000 copies/mL was inversely associated with virologic success at week 48 (HR: 0.22, 95% CI: 0.06-0.85, p = 0.028. CONCLUSIONS: Darunavir/ritonavir plus optimized background therapy was a highly effective salvage regimen under clinical routine conditions in a referral center in Brazil, which is similar to the reported in high-income countries.

  14. Background radiation

    International Nuclear Information System (INIS)

    Arnott, D.

    1985-01-01

    The effects of background radiation, whether natural or caused by man's activities, are discussed. The known biological effects of radiation in causing cancers or genetic mutations are explained. The statement that there is a threshold below which there is no risk is examined critically. (U.K.)

  15. Variations in voice level and fundamental frequency with changing background noise level and talker-to-listener distance while wearing hearing protectors: A pilot study.

    Science.gov (United States)

    Bouserhal, Rachel E; Macdonald, Ewen N; Falk, Tiago H; Voix, Jérémie

    2016-01-01

    Speech production in noise with varying talker-to-listener distance has been well studied for the open ear condition. However, occluding the ear canal can affect the auditory feedback and cause deviations from the models presented for the open-ear condition. Communication is a main concern for people wearing hearing protection devices (HPD). Although practical, radio communication is cumbersome, as it does not distinguish designated receivers. A smarter radio communication protocol must be developed to alleviate this problem. Thus, it is necessary to model speech production in noise while wearing HPDs. Such a model opens the door to radio communication systems that distinguish receivers and offer more efficient communication between persons wearing HPDs. This paper presents the results of a pilot study aimed to investigate the effects of occluding the ear on changes in voice level and fundamental frequency in noise and with varying talker-to-listener distance. Twelve participants with a mean age of 28 participated in this study. Compared to existing data, results show a trend similar to the open ear condition with the exception of the occluded quiet condition. This implies that a model can be developed to better understand speech production for the occluded ear.

  16. Background sources at PEP

    International Nuclear Information System (INIS)

    Lynch, H.; Schwitters, R.F.; Toner, W.T.

    1988-01-01

    Important sources of background for PEP experiments are studied. Background particles originate from high-energy electrons and positrons which have been lost from stable orbits, γ-rays emitted by the primary beams through bremsstrahlung in the residual gas, and synchrotron radiation x-rays. The effect of these processes on the beam lifetime are calculated and estimates of background rates at the interaction region are given. Recommendations for the PEP design, aimed at minimizing background are presented. 7 figs., 4 tabs

  17. Motivation of Dutch high school students from various backgrounds for applying to study medicine: a qualitative study

    Science.gov (United States)

    Wouters, Anouk; Croiset, Gerda; Isik, Ulviye; Kusurkar, Rashmi A

    2017-01-01

    Objective To explore high school students’ motivation for applying to study medicine and the factors that influence this. To find explanations for under-representation of minority students in medical education, descriptions of motivation of students with different background characteristics were compared. Design Qualitative phenomenological study using semistructured one-on-one interviews. Setting One predominantly white and one mixed high school in a large multicultural city in the Netherlands. The study was conducted in March–December 2015. Participants Twenty-four high school students, purposively sampled for demographic characteristics. Methods The analysis consisted of the coding of data using a template based on the motivation types (autonomous and controlled motivation) described by self-determination theory and open coding for factors that influence motivation. Results The main reasons for pursuing a medical career pertained to autonomous motivation (interest in science and helping people), but controlled motivation (eg, parental pressure, prestige) was also mentioned. Experiences with healthcare and patients positively influenced students’ autonomous motivation and served as a reality check for students’ expectations. Having to go through a selection process was an important demotivating factor, but did not prevent most students from applying. Having medical professionals in their network also sparked students’ interest, while facilitating easier access to healthcare experiences. Conclusions The findings showed a complex interplay between healthcare experiences, growing up in a medical family, selection processes and motivation. Healthcare experiences, often one of the selection criteria, help students to form autonomous motivation for studying medicine. However, such experiences as well as support in the selection process seem unequally accessible to students. As a result, under-represented students’ motivation decreases. Medical schools

  18. Development of High Frequency Transition-Edge-Sensor Polarimeters for Next Generation Cosmic Microwave Background Experiments and Galactic Foreground Measurements

    Science.gov (United States)

    Walker, Samantha; Sierra, Carlos E.; Austermann, Jason Edward; Beall, James; Becker, Dan; Dober, Bradley; Duff, Shannon; Hilton, Gene; Hubmayr, Johannes; Van Lanen, Jeffrey L.; McMahon, Jeff; Simon, Sara M.; Ullom, Joel; Vissers, Michael R.; NIST Quantum Sensors Group

    2018-06-01

    Observations of the cosmic microwave background (CMB) provide a powerful tool for probing the earliest moments of the universe and therefore have the potential to transform our understanding of cosmology. In particular, precision measurements of its polarization can reveal the existence of gravitational waves produced during cosmic inflation. However, these observations are complicated by the presence of astrophysical foregrounds, which may be separated by using broad frequency coverage, as the spectral energy distribution between foregrounds and the CMB is distinct. For this purpose, we are developing large-bandwidth, feedhorn-coupled transition-edge-sensor (TES) arrays that couple polarized light from waveguide to superconducting microstrip by use of a symmetric, planar orthomode transducer (OMT). In this work, we describe two types of pixels, an ultra-high frequency (UHF) design, which operates from 195 GHz-315 GHz, and an extended ultra-high frequency (UHF++) design, which operates from 195 GHz-420 GHz, being developed for next generation CMB experiments that will come online in the next decade, such as CCAT-prime and the Simons Observatory. We present the designs, simulation results, fabrication, and preliminary measurements of these prototype pixels.

  19. Discovery of high-level tasks in the operating room

    NARCIS (Netherlands)

    Bouarfa, L.; Jonker, P.P.; Dankelman, J.

    2010-01-01

    Recognizing and understanding surgical high-level tasks from sensor readings is important for surgical workflow analysis. Surgical high-level task recognition is also a challenging task in ubiquitous computing because of the inherent uncertainty of sensor data and the complexity of the operating

  20. Characteristics of solidified high-level waste products

    International Nuclear Information System (INIS)

    1979-01-01

    The object of the report is to contribute to the establishment of a data bank for future preparation of codes of practice and standards for the management of high-level wastes. The work currently in progress on measuring the properties of solidified high-level wastes is being studied

  1. Process for solidifying high-level nuclear waste

    Science.gov (United States)

    Ross, Wayne A.

    1978-01-01

    The addition of a small amount of reducing agent to a mixture of a high-level radioactive waste calcine and glass frit before the mixture is melted will produce a more homogeneous glass which is leach-resistant and suitable for long-term storage of high-level radioactive waste products.

  2. Understanding how roadside concentrations of NOx are influenced by the background levels, traffic density, and meteorological conditions using Boosted Regression Trees

    Science.gov (United States)

    Sayegh, Arwa; Tate, James E.; Ropkins, Karl

    2016-02-01

    Oxides of Nitrogen (NOx) is a major component of photochemical smog and its constituents are considered principal traffic-related pollutants affecting human health. This study investigates the influence of background concentrations of NOx, traffic density, and prevailing meteorological conditions on roadside concentrations of NOx at UK urban, open motorway, and motorway tunnel sites using the statistical approach Boosted Regression Trees (BRT). BRT models have been fitted using hourly concentration, traffic, and meteorological data for each site. The models predict, rank, and visualise the relationship between model variables and roadside NOx concentrations. A strong relationship between roadside NOx and monitored local background concentrations is demonstrated. Relationships between roadside NOx and other model variables have been shown to be strongly influenced by the quality and resolution of background concentrations of NOx, i.e. if it were based on monitored data or modelled prediction. The paper proposes a direct method of using site-specific fundamental diagrams for splitting traffic data into four traffic states: free-flow, busy-flow, congested, and severely congested. Using BRT models, the density of traffic (vehicles per kilometre) was observed to have a proportional influence on the concentrations of roadside NOx, with different fitted regression line slopes for the different traffic states. When other influences are conditioned out, the relationship between roadside concentrations and ambient air temperature suggests NOx concentrations reach a minimum at around 22 °C with high concentrations at low ambient air temperatures which could be associated to restricted atmospheric dispersion and/or to changes in road traffic exhaust emission characteristics at low ambient air temperatures. This paper uses BRT models to study how different critical factors, and their relative importance, influence the variation of roadside NOx concentrations. The paper

  3. The ATLAS High-Level Calorimeter Trigger in Run-2

    CERN Document Server

    Wiglesworth, Craig; The ATLAS collaboration

    2018-01-01

    The ATLAS Experiment uses a two-level triggering system to identify and record collision events containing a wide variety of physics signatures. It reduces the event rate from the bunch-crossing rate of 40 MHz to an average recording rate of 1 kHz, whilst maintaining high efficiency for interesting collision events. It is composed of an initial hardware-based level-1 trigger followed by a software-based high-level trigger. A central component of the high-level trigger is the calorimeter trigger. This is responsible for processing data from the electromagnetic and hadronic calorimeters in order to identify electrons, photons, taus, jets and missing transverse energy. In this talk I will present the performance of the high-level calorimeter trigger in Run-2, noting the improvements that have been made in response to the challenges of operating at high luminosity.

  4. Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran.

    Science.gov (United States)

    Mortazavi, Seyed Mohammad Javad; Zarei, Samira; Taheri, Mohammad; Tajbakhsh, Saeed; Mortazavi, Seyed Alireza; Ranjbar, Sahar; Momeni, Fatemeh; Masoomi, Samaneh; Ansari, Leila; Movahedi, Mohammad Mehdi; Taeb, Shahram; Zarei, Sina; Haghani, Masood

    2017-04-01

    Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium ( S. typhimurium ), Staphylococcus aureus , and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

  5. Teen Dating Violence Victimization among High School Students: A Multilevel Analysis of School-Level Risk Factors

    Science.gov (United States)

    Parker, Elizabeth M.; Johnson, Sarah Lindstrom; Debnam, Katrina J.; Milam, Adam J.; Bradshaw, Catherine P.

    2017-01-01

    Background: Much etiologic research has focused on individual-level risk factors for teen dating violence (TDV); therefore, less is known about school-level and neighborhood-level risk factors. We examined the association between alcohol outlet density around high schools and TDV victimization and the association between markers of physical…

  6. Predictors of Placement in Lower Level versus Higher Level High School Mathematics

    Science.gov (United States)

    Archbald, Doug; Farley-Ripple, Elizabeth N.

    2012-01-01

    Educators and researchers have long been interested in determinants of access to honors level and college prep courses in high school. Factors influencing access to upper level mathematics courses are particularly important because of the hierarchical and sequential nature of this subject and because students who finish high school with only lower…

  7. Stable superconducting magnet. [high current levels below critical temperature

    Science.gov (United States)

    Boom, R. W. (Inventor)

    1967-01-01

    Operation of a superconducting magnet is considered. A method is described for; (1) obtaining a relatively high current in a superconducting magnet positioned in a bath of a gas refrigerant; (2) operating a superconducting magnet at a relatively high current level without training; and (3) operating a superconducting magnet containing a plurality of turns of a niobium zirconium wire at a relatively high current level without training.

  8. Establishment of immortalized B lymphoblastoid cell lines of old residents in high background radiation area in Guangdong, China

    International Nuclear Information System (INIS)

    Lu Xue; Feng Jiangbing; Chen Deqing; Liu Qingjie; Cha Yongru; Zou Jianming

    2008-01-01

    Objective: To establish the immortalized cell lines of peripheral blood lymphocytes for old male residents in high background radiation area (HBRA) in Guangdong, China, in order to preserve the specific genomic resources of residents in HBRA for the further genetic and molecular biological study on HBRA. Methods: The peripheral blood samples of 20 old male residents in HBRA were collected after informed consent. The immortalized B lymphoblastoid cell lines, 2 fox each resident, were established with Epstein-Barr virus. After being frozen and recovered, the cell viability, the contamination of bacterium and mycoplasma were analyzed. The stabilization of cell lines was decided by comparing the karyotypes of the peripheral blood lymphocytes and the cell lines. Results: 40 cell lines for 20 residents in HBRA were successfully established.. The recovery rate of cell lines after being frozen was 100% . All the cell viablity after recovery was higher than 90%, and no contamination of bacteria and mycoplasma occurred. The karyotypes of the 20th generation cell lines were not change. Conclusion: The immortalized cell lines established in this study could provide biological resources for further study on genetics and molecular biology in HBRA. (authors)

  9. Measurement of 222Rn, 220Rn and their decay products in high background radiation area in Yangjiang

    International Nuclear Information System (INIS)

    Yuan Yongling

    2000-01-01

    The investigators have measured concentrations of Rn-222, rn-220 and their decay products in high background radiation area (HBRA) and the neighboring control area (CA), as well as the equilibrium factor F for Rn-222. The average concentrations of Rn-222 in the air indoors and outdoors in the HBRA are 42.6 and 17.3 Bq/m 3 respectively, and CA, 13.2 and 11.7 Bq/m 3 , respectively. The average α-potential energy concentrations for daughters of Rn-222 indoors and outdoors in HBRA are 0.109 and 0.051 μJ/m 3 , CA, 0.045 and 0.041 μJ/m 3 , respectively. The average α-potential energy values for daughters of Rn-220 indoor and outdoor in HBRA are 0.249 and 0.053 μJ/m 3 , CA, 0.051 and 0.025 μJ/m 3 , respectively. With regard to equilibrium factor F for Rn-222, the authors have also measured 52 points of 10 hamlets in HBRA (indoor 31, outdoor 21), 9 points of 2 hamlets in CA (indoor 5, outdoor 4), respectively. These figures are 0.46, 0.53, 0.62 and 0.64, respectively

  10. Exceedance probability map: a tool helping the definition of arsenic Natural Background Level (NBL) within the Drainage Basin to the Venice Lagoon (NE Italy)

    Science.gov (United States)

    Dalla Libera, Nico; Fabbri, Paolo; Mason, Leonardo; Piccinini, Leonardo; Pola, Marco

    2017-04-01

    Arsenic groundwater contamination affects worldwide shallower groundwater bodies. Starting from the actual knowledges around arsenic origin into groundwater, we know that the major part of dissolved arsenic is naturally occurring through the dissolution of As-bearing minerals and ores. Several studies on the shallow aquifers of both the regional Venetian Plain (NE Italy) and the local Drainage Basin to the Venice Lagoon (DBVL) show local high arsenic concentration related to peculiar geochemical conditions, which drive arsenic mobilization. The uncertainty of arsenic spatial distribution makes difficult both the evaluation of the processes involved in arsenic mobilization and the stakeholders' decision about environmental management. Considering the latter aspect, the present study treats the problem of the Natural Background Level (NBL) definition as the threshold discriminating the natural contamination from the anthropogenic pollution. Actually, the UE's Directive 2006/118/EC suggests the procedures and criteria to set up the water quality standards guaranteeing a healthy status and reversing any contamination trends. In addition, the UE's BRIDGE project proposes some criteria, based on the 90th percentile of the contaminant's concentrations dataset, to estimate the NBL. Nevertheless, these methods provides just a statistical NBL for the whole area without considering the spatial variation of the contaminant's concentration. In this sense, we would reinforce the NBL concept using a geostatistical approach, which is able to give some detailed information about the distribution of arsenic concentrations and unveiling zones with high concentrations referred to the Italian drinking water standard (IDWS = 10 µg/liter). Once obtained the spatial information about arsenic distribution, we can apply the 90th percentile methods to estimate some Local NBL referring to every zones with arsenic higher than IDWS. The indicator kriging method was considered because it

  11. Analysis of the clinical backgrounds of patients who developed respiratory acidosis under high-flow oxygen therapy during emergency transport.

    Science.gov (United States)

    Ogino, Hirokazu; Nishimura, Naoki; Yamano, Yasuhiko; Ishikawa, Genta; Tomishima, Yutaka; Jinta, Torahiko; Takahashi, Osamu; Chohnabayashi, Naohiko

    2016-01-01

    High-flow oxygen is often administered to patients during emergency transport and can sometimes cause respiratory acidosis with disturbed consciousness, thereby necessitating mechanical ventilation. Although oxygen titration in chronic obstructive pulmonary disease patients during emergency transport reduces mortality rates, the clinical risk factors for respiratory acidosis in emergency settings are not fully understood. Therefore, we analyzed the clinical backgrounds of patients who developed respiratory acidosis during pre-hospital transport. This was a retrospective study of patients who arrived at our hospital by emergency transport in 2010 who received high-flow oxygen while in transit. Respiratory acidosis was defined by the following arterial blood gas readings: pH, ≤7.35; PaCO 2 , ≥45 mmHg; and HCO 3 - , ≥24 mmol/L. The risk factors were identified using multivariable logistic regression analysis. In 765 study patients, 66 patients showed respiratory acidosis. The following risk factors for respiratory acidosis were identified: age, ≥65 years (odds ratio [OR] 1.4; 95% confidence interval [CI], 0.7-2.8); transportation time, ≥10 min (OR 2.0; 95% CI, 1.1-3.7); three digits on the Japan Coma Scale (OR 3.1; 95% CI, 1.7-5.8); percutaneous oxygen saturation, ≤90% (OR 1.6; 95% CI, 0.8-3.0); tuberculosis (OR 4.5; 95% CI, 1.4-15.1); asthma (OR 1.8; 95% CI, 0.6-5.3); pneumonia (OR 1.5; 95% CI, 0.7-3.1); and lung cancer (OR 3.9; 95% CI, 1.5-10.1). These underlying diseases as risk factors included both comorbid diseases and past medical conditions. The factors identified may contribute to the development of respiratory acidosis. Further studies on preventing respiratory acidosis will improve the quality of emergency medical care.

  12. High-level waste immobilization program: an overview

    International Nuclear Information System (INIS)

    Bonner, W.R.

    1979-09-01

    The High-Level Waste Immobilization Program is providing technology to allow safe, affordable immobilization and disposal of nuclear waste. Waste forms and processes are being developed on a schedule consistent with national needs for immobilization of high-level wastes stored at Savannah River, Hanford, Idaho National Engineering Laboratory, and West Valley, New York. This technology is directly applicable to high-level wastes from potential reprocessing of spent nuclear fuel. The program is removing one more obstacle previously seen as a potential restriction on the use and further development of nuclear power, and is thus meeting a critical technological need within the national objective of energy independence

  13. National high-level waste systems analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Kristofferson, K.; Oholleran, T.P.; Powell, R.H.

    1995-09-01

    This report documents the assessment of budgetary impacts, constraints, and repository availability on the storage and treatment of high-level waste and on both existing and pending negotiated milestones. The impacts of the availabilities of various treatment systems on schedule and throughput at four Department of Energy sites are compared to repository readiness in order to determine the prudent application of resources. The information modeled for each of these sites is integrated with a single national model. The report suggests a high-level-waste model that offers a national perspective on all high-level waste treatment and storage systems managed by the Department of Energy.

  14. National high-level waste systems analysis report

    International Nuclear Information System (INIS)

    Kristofferson, K.; Oholleran, T.P.; Powell, R.H.

    1995-09-01

    This report documents the assessment of budgetary impacts, constraints, and repository availability on the storage and treatment of high-level waste and on both existing and pending negotiated milestones. The impacts of the availabilities of various treatment systems on schedule and throughput at four Department of Energy sites are compared to repository readiness in order to determine the prudent application of resources. The information modeled for each of these sites is integrated with a single national model. The report suggests a high-level-waste model that offers a national perspective on all high-level waste treatment and storage systems managed by the Department of Energy

  15. Analysis of environmental effects from disposal of solidified ICPP high-level wastes

    International Nuclear Information System (INIS)

    Chipman, N.A.; Simpson, G.G.; Lawroski, H.; Rodger, W.A.; Frendberg, R.L.

    1979-01-01

    This work is part of a comprehensive study to assess possible environmental impacts from six different options for managing high-level defense wastes generated at the ICPP. Only radiological consequences are considered in this report; population doses to those within 80 km of ICPP were estimated for time periods up to 100 million years. The population dose to future generations from any option is insignificant compared with that from natural background radiation: less than 1 cancer death in 1,000 years compared with 20,000 cancer deaths from natural background radiation. 16 tables

  16. Motivation of Dutch high school students from various backgrounds for applying to study medicine: a qualitative study.

    Science.gov (United States)

    Wouters, Anouk; Croiset, Gerda; Isik, Ulviye; Kusurkar, Rashmi A

    2017-06-02

    To explore high school students' motivation for applying to study medicine and the factors that influence this. To find explanations for under-representation of minority students in medical education, descriptions of motivation of students with different background characteristics were compared. Qualitative phenomenological study using semistructured one-on-one interviews. One predominantly white and one mixed high school in a large multicultural city in the Netherlands. The study was conducted in March-December 2015. Twenty-four high school students, purposively sampled for demographic characteristics. The analysis consisted of the coding of data using a template based on the motivation types (autonomous and controlled motivation) described by self-determination theory and open coding for factors that influence motivation. The main reasons for pursuing a medical career pertained to autonomous motivation (interest in science and helping people), but controlled motivation (eg, parental pressure, prestige) was also mentioned. Experiences with healthcare and patients positively influenced students' autonomous motivation and served as a reality check for students' expectations. Having to go through a selection process was an important demotivating factor, but did not prevent most students from applying. Having medical professionals in their network also sparked students' interest, while facilitating easier access to healthcare experiences. The findings showed a complex interplay between healthcare experiences, growing up in a medical family, selection processes and motivation. Healthcare experiences, often one of the selection criteria, help students to form autonomous motivation for studying medicine. However, such experiences as well as support in the selection process seem unequally accessible to students. As a result, under-represented students' motivation decreases. Medical schools should be aware of this and could create opportunities to acquire healthcare

  17. The ATLAS high level trigger region of interest builder

    International Nuclear Information System (INIS)

    Blair, R.; Dawson, J.; Drake, G.; Haberichter, W.; Schlereth, J.; Zhang, J.; Ermoline, Y.; Pope, B.; Aboline, M.; High Energy Physics; Michigan State Univ.

    2008-01-01

    This article describes the design, testing and production of the ATLAS Region of Interest Builder (RoIB). This device acts as an interface between the Level 1 trigger and the high level trigger (HLT) farm for the ATLAS LHC detector. It distributes all of the Level 1 data for a subset of events to a small number of (16 or less) individual commodity processors. These processors in turn provide this information to the HLT. This allows the HLT to use the Level 1 information to narrow data requests to areas of the detector where Level 1 has identified interesting objects

  18. Metal-as-insulation variant of no-insulation HTS winding technique: pancake tests under high background magnetic field and high current at 4.2 K

    Science.gov (United States)

    Lécrevisse, T.; Badel, A.; Benkel, T.; Chaud, X.; Fazilleau, P.; Tixador, P.

    2018-05-01

    In the framework of a project aiming at fabricating a 10 T high temperature superconducting (HTS) insert to operate in a 20 T background field, we are investigating the behavior of pancakes consisting of a REBCO HTS tape co-wound with a stainless steel tape (metal-as-insulation (MI) coil). The MI winding is inducing a significant turn-to-turn electrical resistance which helps to reduce the charging time delay. Despite this resistance, the self-protection feature of no-insulation coils is still enabled, thanks to the voltage limit of the power supply. We have built a single pancake coil representative of the pancake that will be used in the insert and performed tests under very high background magnetic field. Our coil experienced over 100 heater induced quenches without a measureable increase of its internal resistance. We have gathered stability and quench behavior data for magnetic fields and engineering current densities (je ) in the range of 0–17 T and 0–635 A mm‑2 respectively. We also present our very first experiments on the insert/outsert interaction in the case of a resistive magnet fault. We show that if self-protection of the MI winding is really effective in the case of a MI coil quench, a major issue comes from the outsert fault which induces a huge current inside the MI coil.

  19. NOS CO-OPS Water Level Data, Verified, High Low

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has verified (quality-controlled), daily, high low water level (tide) data from NOAA NOS Center for Operational Oceanographic Products and Services...

  20. Artificial Heads for High-Level Impulse Sound Measurement

    National Research Council Canada - National Science Library

    Buck, K

    1999-01-01

    If the Insertion Loss (IL) of hearing protectors has to be determined with very high impulse or continuous noise levels, the acoustic insulation of the Artificial Test Fixture has to exceed at least the Insertion Loss (IL...

  1. Technical career opportunities in high-level radioactive waste management

    International Nuclear Information System (INIS)

    1993-01-01

    Technical career opportunities in high-level radioactive waste management are briefly described in the areas of: Hydrology; geology; biological sciences; mathematics; engineering; heavy equipment operation; and skilled labor and crafts

  2. Long-term high-level waste technology program

    International Nuclear Information System (INIS)

    1980-04-01

    The Department of Energy (DOE) is conducting a comprehensive program to isolate all US nuclear wastes from the human environment. The DOE Office of Nuclear Energy - Waste (NEW) has full responsibility for managing the high-level wastes resulting from defense activities and additional responsiblity for providing the technology to manage existing commercial high-level wastes and any that may be generated in one of several alternative fuel cycles. Responsibilities of the Three Divisions of DOE-NEW are shown. This strategy document presents the research and development plan of the Division of Waste Products for long-term immobilization of the high-level radioactive wastes resulting from chemical processing of nuclear reactor fuels and targets. These high-level wastes contain more than 99% of the residual radionuclides produced in the fuels and targets during reactor operations. They include essentially all the fission products and most of the actinides that were not recovered for use

  3. Glasses used for the high level radioactive wastes storage

    International Nuclear Information System (INIS)

    Sombret, C.

    1983-06-01

    High level radioactive wastes generated by the reprocessing of spent fuels is an important concern in the conditioning of radioactive wastes. This paper deals with the status of the knowledge about glasses used for the treatment of these liquids [fr

  4. Development of melt compositions for sulphate bearing high level waste

    International Nuclear Information System (INIS)

    Jahagirdar, P.B.; Wattal, P.K.

    1997-09-01

    The report deals with the development and characterization of vitreous matrices for sulphate bearing high level waste. Studies were conducted in sodium borosilicate and lead borosilicate systems with the introduction of CaO, BaO, MgO etc. Lead borosilicate system was found to be compatible with sulphate bearing high level wastes. Detailed product evaluation carried on selected formulations is also described. (author)

  5. Properties and characteristics of high-level waste glass

    International Nuclear Information System (INIS)

    Ross, W.A.

    1977-01-01

    This paper has briefly reviewed many of the characteristics and properties of high-level waste glasses. From this review, it can be noted that glass has many desirable properties for solidification of high-level wastes. The most important of these include: (1) its low leach rate; (2) the ability to tolerate large changes in waste composition; (3) the tolerance of anticipated storage temperatures; (4) its low surface area even after thermal shock or impact

  6. High-Level Waste System Process Interface Description

    International Nuclear Information System (INIS)

    D'Entremont, P.D.

    1999-01-01

    The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment

  7. High level waste canister emplacement and retrieval concepts study

    International Nuclear Information System (INIS)

    1975-09-01

    Several concepts are described for the interim (20 to 30 years) storage of canisters containing high level waste, cladding waste, and intermediate level-TRU wastes. It includes requirements, ground rules and assumptions for the entire storage pilot plant. Concepts are generally evaluated and the most promising are selected for additional work. Follow-on recommendations are made

  8. Long open-path TDL based system for monitoring background concentration for deployment at Jungfraujoch High Altitude Research Station- Switzerland

    Science.gov (United States)

    Simeonov, Valentin; van den Bergh, Hubert; Parlange, Marc

    2010-05-01

    A new, long open-path instrument for monitoring of path-averaged methane and water vapor concentrations will be presented. The instrument is built on the monostatic scheme (transceiver - distant retroreflector). A VCSEL tunable diode laser (TDL) with a central wavelength of 1654 nm is used as a light source. A specially designed, single-cell, hollow-cube retroreflector with 150 mm aperture will be installed at 1200 m from the transceiver in the final deployment at Jungfraujjoch and 100 mm retroreflectors will be used in the other applications. The receiver is built around a 20 cm Newtonian telescope. To avoid distortions in the shape of a methane line, caused by atmospheric turbulences, the line is scanned within 1 µs. Fast InGaAs photodiodes and 200 MHz are used to achieve this scanning rate. The expected concentration resolution for the above mentioned path lengths is of the order of 2 ppb. The instrument is developed at the Swiss Federal Institute of Technology - Lausanne (EPFL) Switzerland and will be used within the GAW+ CH program for long-term monitoring of background methane concentration in the Swiss Alps. After completing the initial tests at EPFL the instrument will be installed in 2012 at the High Altitude Research Station Jungfraujoch (HARSJ) located at 3580 m ASL. The HARSJ is one of the 24 global GAW stations and carries on continuous observations of a number of trace gasses, including methane. One of the goals of the project is to compare path-averaged to ongoing point measurements of methane in order to identify possible influence of the station. Future deployments of a copy of the instrument include the Colombian part of Amazonia and Siberian wetlands.

  9. Reanalysis of noncancer deaths (1987-1995) among residents in high background radiation area of Yangjiang, China

    International Nuclear Information System (INIS)

    Zou Jianming; Zha Yongru; Sun Quanfu; Liu Yusheng; Li Jia; Tao Zufan; Wei Lvxin

    2004-01-01

    Objective: To further analyze non-cancer mortality rates and relevant influencing factors among the residents in high background radiation area(HBRA) and its control area (CA). Methods: The data for the period 1987-1995 were obtained from a fixed cohort by prospective survey. The mortality investigation on the spot consisted of two steps, i.e. the follow-up of the cohort members and the ascertainment of causes of death. On the basis of the hamlet-specific average of annual external dose, the cohort members were classified into four groups for internal comparison: high, medial and low dose groups in HBRA and control group in CA. Relative risk (RR), excess relative risk(ERR/Sv) and its 95% confidence interval (CI) were estimated using AMFIT program in Epicure. Results: During the period 1987-1995, the noncancer mortality in HBRA increased by 9% compared with that in the control group, and the relative risk of noncancer diseases was 1.09 (P=0.01), indicating a statistically significant excess mortality in the HBRA. The significantly increased noncancer death was caused by diseases of digestive system, with a RR of 1.46(P=0.006); the relative risk of chronic liver diseases including cirrhosis was 1.98(P=0.004). The significantly decreased noncancer death rates were observed for the infectious and parasitic diseases, the RR being 0.81(P=0.04); for pulmonary tuberculosis, RR 0.58(P<0.001). The homogeneity tests of risks across the four dose-groups revealed that the RRs for diseases of digestive system and for liver cirrhosis were significantly different, P values being 0.01 and 0.04, respectively. The ERR(95% CI)/Sv for diseases of digestive system and liver cirrhosis were 2.18(0.22, 7.64) and 10.94(1.34, NA), respectively. Conclusion: The death rates from diseases of digestive system, especially chronic liver diseases and cirrhosis were statistically significantly higher, and that from pulmonary tuberculosis was significantly lower in the HBRA than those in the control

  10. The sleep of elite athletes at sea level and high altitude: a comparison of sea-level natives and high-altitude natives (ISA3600)

    Science.gov (United States)

    Roach, Gregory D; Schmidt, Walter F; Aughey, Robert J; Bourdon, Pitre C; Soria, Rudy; Claros, Jesus C Jimenez; Garvican-Lewis, Laura A; Buchheit, Martin; Simpson, Ben M; Hammond, Kristal; Kley, Marlen; Wachsmuth, Nadine; Gore, Christopher J; Sargent, Charli

    2013-01-01

    Background Altitude exposure causes acute sleep disruption in non-athletes, but little is known about its effects in elite athletes. The aim of this study was to examine the effects of altitude on two groups of elite athletes, that is, sea-level natives and high-altitude natives. Methods Sea-level natives were members of the Australian under-17 soccer team (n=14). High-altitude natives were members of a Bolivian under-20 club team (n=12). Teams participated in an 18-day (19 nights) training camp in Bolivia, with 6 nights at near sea level in Santa Cruz (430 m) and 13 nights at high altitude in La Paz (3600 m). Sleep was assessed on every day/night using activity monitors. Results The Australians’ sleep was shorter, and of poorer quality, on the first night at altitude compared with sea level. Sleep quality returned to normal by the end of the first week at altitude, but sleep quantity had still not stabilised at its normal level after 2 weeks. The quantity and quality of sleep obtained by the Bolivians was similar, or greater, on all nights at altitude compared with sea level. The Australians tended to obtain more sleep than the Bolivians at sea level and altitude, but the quality of the Bolivians’ sleep tended to be better than that of the Australians at altitude. Conclusions Exposure to high altitude causes acute and chronic disruption to the sleep of elite athletes who are sea-level natives, but it does not affect the sleep of elite athletes who are high-altitude natives. PMID:24282197

  11. Elevated level of polysaccharides in a high level UV-B tolerant cell ...

    African Journals Online (AJOL)

    Jane

    2011-04-26

    Apr 26, 2011 ... A cell line of Bupleurum scorzonerifolium Willd with high level ... mechanisms to repair UV-induced damages via repairing ... for treatment or prevention of solar radiation. ..... working as both UV-B absorbing compounds and.

  12. High level of CA 125 due to large endometrioma.

    Science.gov (United States)

    Phupong, Vorapong; Chen, Orawan; Ultchaswadi, Pornthip

    2004-09-01

    CA 125 is a tumor-associated antigen. Its high levels are usually associated with ovarian malignancies, whereas smaller increases in the levels were associated with benign gynecologic conditions. The authors report a high level of CA 125 in a case of large ovarian endometrioma. A 45-year-old nulliparous Thai woman, presented with an increase of her abdominal girth for 7 months. Transabdominal ultrasonogram demonstrated a large ovarian cyst and multiple small leiomyoma uteri, and serum CA 125 level was 1,006 U/ml. The preoperative diagnosis was ovarian cancer with leiomyoma uteri. Exploratory laparotomy was performed. There were a large right ovarian endometrioma, small left ovarian endometrioma and multiple small leiomyoma. Total abdominal hysterectomy and bilateral salpingo-oophorectomy was performed and histopathology confirmed the diagnosis of endometrioma and leiomyoma. The serum CA 125 level declined to non-detectable at the 4th week. She was well at discharge and throughout her 4th week follow-up period Although a very high level of CA 125 is associated with a malignant process, it can also be found in benign conditions such as a large endometrioma. The case emphasizes the association of high levels of CA 125 with benign gynecologic conditions.

  13. Transition to Kindergarten: Negative Associations between the Emotional Availability in Mother–Child Relationships and Elevated Cortisol Levels in Children with an Immigrant Background

    Directory of Open Access Journals (Sweden)

    Constanze Rickmeyer

    2017-05-01

    Full Text Available Background: The transition to child care is a challenging time in a child’s life and leads to elevated levels of cortisol. These elevations may be influenced by the quality of the mother–child relationship. However, remarkably little is known about cortisol production in response to the beginning of child care among children-at-risk such as children with an immigrant background. However, attending kindergarten or any other child day-care institution can for example have a compensating effect on potential language deficits thus improving the educational opportunities of these children.Method: Data of a subsample of N = 24 “hard-to-reach” mother–child dyads was collected in the context of the psychoanalytic early prevention project FIRST STEPS. The project focuses on the earliest integration of children with an immigrant background by supporting parenting capacities in the critical phase of migration and early parenthood. Children’s hair cortisol concentration (HCC was assessed 1 week before (mean age = 38.77 months and 3 months after kindergarten entry (mean age = 42.26 months. Hair analysis was conducted for both times of measurement, reflecting the first 3 months after kindergarten entry and 3 months prior. Furthermore, the emotional quality of the mother–child relationship was assessed with the help of the Emotional Availability Scales (EAS; Biringen, 2008 shortly before kindergarten entry when the children were about 3 years old (mean age = 37.2.Results and Conclusion: Children’s mean cumulated HCC was higher after kindergarten entry than before. The increase correlated negatively with several dimensions of the EAS. Repeated measures ANCOVA revealed that particularly responsive children and children who had experienced less intrusive mother–child relationships demonstrated lower elevations in HCC after kindergarten entry. Furthermore, a decreased EA score was found in all EA dimensions, besides the dimension

  14. Transition to Kindergarten: Negative Associations between the Emotional Availability in Mother–Child Relationships and Elevated Cortisol Levels in Children with an Immigrant Background

    Science.gov (United States)

    Rickmeyer, Constanze; Lebiger-Vogel, Judith; Leuzinger-Bohleber, Marianne

    2017-01-01

    Background: The transition to child care is a challenging time in a child’s life and leads to elevated levels of cortisol. These elevations may be influenced by the quality of the mother–child relationship. However, remarkably little is known about cortisol production in response to the beginning of child care among children-at-risk such as children with an immigrant background. However, attending kindergarten or any other child day-care institution can for example have a compensating effect on potential language deficits thus improving the educational opportunities of these children. Method: Data of a subsample of N = 24 “hard-to-reach” mother–child dyads was collected in the context of the psychoanalytic early prevention project FIRST STEPS. The project focuses on the earliest integration of children with an immigrant background by supporting parenting capacities in the critical phase of migration and early parenthood. Children’s hair cortisol concentration (HCC) was assessed 1 week before (mean age = 38.77 months) and 3 months after kindergarten entry (mean age = 42.26 months). Hair analysis was conducted for both times of measurement, reflecting the first 3 months after kindergarten entry and 3 months prior. Furthermore, the emotional quality of the mother–child relationship was assessed with the help of the Emotional Availability Scales (EAS; Biringen, 2008) shortly before kindergarten entry when the children were about 3 years old (mean age = 37.2). Results and Conclusion: Children’s mean cumulated HCC was higher after kindergarten entry than before. The increase correlated negatively with several dimensions of the EAS. Repeated measures ANCOVA revealed that particularly responsive children and children who had experienced less intrusive mother–child relationships demonstrated lower elevations in HCC after kindergarten entry. Furthermore, a decreased EA score was found in all EA dimensions, besides the dimension “mother’s non

  15. Delivering high-level food industry skills for future food security through Advanced Training Partnerships

    OpenAIRE

    Frazier, Richard A.

    2013-01-01

    The UK Biotechnology and Biological Sciences Research Council’s Advanced Training Partnerships initiative represents a significant investment in the provision of high-level skills for the UK food industry sector to address global food security from farm to fork. This paper summarises the background, aims and scope of the Advanced Training Partnerships, their development so far, and offers a view on future directions and evaluation of impact.

  16. Treatment of High-Level Waste Arising from Pyrochemical Processes

    International Nuclear Information System (INIS)

    Lizin, A.A.; Kormilitsyn, M.V.; Osipenko, A.G.; Tomilin, S.V.; Lavrinovich, Yu.G.

    2013-01-01

    JSC “SSC RIAR” has been performing research and development activities in support of closed fuel cycle of fast reactor since the middle of 1960s. Fuel cycle involves fabrication and reprocessing of spent nuclear fuel (SNF) using pyrochemical methods of reprocessing in molten alkali metal chlorides. At present pyrochemical methods of SNF reprocessing in molten chlorides has reached such a level in their development that makes it possible to compare their competitiveness with classic aqueous methods. Their comparative advantage lies in high safety, compactness, high protectability as to nonproliferation of nuclear materials, and reduction of high level waste volume

  17. High-level trigger system for the LHC ALICE experiment

    CERN Document Server

    Bramm, R; Lien, J A; Lindenstruth, V; Loizides, C; Röhrich, D; Skaali, B; Steinbeck, T M; Stock, Reinhard; Ullaland, K; Vestbø, A S; Wiebalck, A

    2003-01-01

    The central detectors of the ALICE experiment at LHC will produce a data size of up to 75 MB/event at an event rate less than approximately equals 200 Hz resulting in a data rate of similar to 15 GB/s. Online processing of the data is necessary in order to select interesting (sub)events ("High Level Trigger"), or to compress data efficiently by modeling techniques. Processing this data requires a massive parallel computing system (High Level Trigger System). The system will consist of a farm of clustered SMP-nodes based on off- the-shelf PCs connected with a high bandwidth low latency network.

  18. Alterations in lipids & lipid peroxidation in rats fed with flavonoid rich fraction of banana (Musa paradisiaca) from high background radiation area.

    Science.gov (United States)

    Krishnan, Kripa; Vijayalakshmi, N R

    2005-12-01

    A group of villages in Kollam district of Kerala, southern part of India are exposed to a higher dose of natural radiation than global average. Yet no adverse health effects have been found in humans, animals and plants in these areas. The present study was carried out to understand whether radiation affects the quantity and quality of flavonoids in plants grown in this area of high radiation, and to assess the effect of feeding flavonoid rich fraction (FRF) of the two varieties of banana to rats on their biochemical parameters like lipids, lipid peroxides and antioxidant enzyme levels. A total of 42 albino rats were equally divided into 7 groups. Rats fed laboratory diet alone were grouped under group I (normal control). Groups II and V received flavonoid rich fraction (FRF) from the fruits of two varieties of Musa paradisiaca, Palayamkodan and Rasakadali respectively from normal background radiation area (Veli) and treated as controls. Rats of groups III and IV received FRF of Palayamkodan from high background radiation areas (HBRAs) - Neendakara and Karunagappally respectively while groups VI and VII received FRF of Rasakadali from HBRAs. At the end of the experimental period of 45 days, lipids, lipid peroxides and antioxidant enzymes from liver, heart and kidney were analyzed. FRF of Palayamkodan and Rasakadali varieties showed significant hypolipidaemic and antioxidant activities. But these activities were found to be lowered in plants grown in HBRAs, particularly in Karunagappally area. Of the two, Palayamkodan variety was more effective in reducing lipids and lipid peroxides. MDA and hydroperoxides were significantly diminished in rats given FRF of banana from Veli (control area) only. FRF from plants grown in HBRAs exerted inhibition in the activities of antioxidant enzymes in the liver of rats and this inhibitory effect was maximum in rats fed FRF from Karunagappally. Banana grown in HBRAs is of lower quality with less efficient antioxidant system

  19. Biosorption of cadmium by Brevundimonas sp. ZF12 strain, a novel biosorbent isolated from hot-spring waters in high background radiation areas

    International Nuclear Information System (INIS)

    Masoudzadeh, Nasrin; Zakeri, Fardideh; Lotfabad, Tayebe bagheri; Sharafi, Hakimeh; Masoomi, Fatemeh; Zahiri, Hoseein Shahbani; Ahmadian, Gholamreza; Noghabi, Kambiz Akbari

    2011-01-01

    Highlights: ► Isolation and characterization of a novel cadmium-biosorbent (Brevundimonas sp. ZF12) from high background radiation areas. ► Brevundimonas sp. ZF12 caused 50% removal of cadmium at the concentration level of 250 ppm. ► Solution pH values used for the reusability study have powerful desorptive features to recover Cd ions sorbed onto the biomass. ► This is the first study carried out so far for the cadmium removal from aqueous solutions by a novel biosorbent Brevundimonas sp. ZF12. ► In our opinion, the isolate can be an attractive alternative to remove the cadmium-containing wastewaters. - Abstract: The aim of this study is to screen cadmium biosorbing bacterial strains isolated from soils and hot-springs containing high concentrations of radium ( 226 Ra) in Ramsar using a batch system. Brevundimonas sp. ZF12 strain isolated from the water with high 226 Ra content caused 50% removal of cadmium at a concentration level of 250 ppm. The biosorption equilibrium data are fitted well by the Langmuir adsorption isotherm and kinetic studies indicated that the biosorption follows pseudo second-order model. The effect of different physico-chemical parameters like biomass concentration, pH, cadmium concentration, temperature and contact time on cadmium sorption was also investigated using FTIR, SEM and XRD analytical techniques. A high desorption efficiency (above 90%) was obtained using a pH range of 2.0–4.0. Reusability of the biomass was examined under consecutive biosorption–desorption cycles repeated thrice. In conclusion, Brevundimonas sp. ZF12 is proposed as an excellent cadmium biosorbent that may have important applications in Cd removal from wastewaters.

  20. Investigation of the Effects of Facility Background Pressure on the Performance and Voltage-Current Characteristics of the High Voltage Hall Accelerator

    Science.gov (United States)

    Kamhawi, Hani; Huang, Wensheng; Haag, Thomas; Spektor, Rostislav

    2014-01-01

    The National Aeronautics and Space Administration (NASA) Science Mission Directorate In-Space Propulsion Technology office is sponsoring NASA Glenn Research Center to develop a 4 kW-class Hall thruster propulsion system for implementation in NASA science missions. A study was conducted to assess the impact of varying the facility background pressure on the High Voltage Hall Accelerator (HiVHAc) thruster performance and voltage-current characteristics. This present study evaluated the HiVHAc thruster performance in the lowest attainable background pressure condition at NASA GRC Vacuum Facility 5 to best simulate space-like conditions. Additional tests were performed at selected thruster operating conditions to investigate and elucidate the underlying physics that change during thruster operation at elevated facility background pressure. Tests were performed at background pressure conditions that are three and ten times higher than the lowest realized background pressure. Results indicated that the thruster discharge specific impulse and efficiency increased with elevated facility background pressure. The voltage-current profiles indicated a narrower stable operating region with increased background pressure. Experimental observations of the thruster operation indicated that increasing the facility background pressure shifted the ionization and acceleration zones upstream towards the thruster's anode. Future tests of the HiVHAc thruster are planned at background pressure conditions that are expected to be two to three times lower than what was achieved during this test campaign. These tests will not only assess the impact of reduced facility background pressure on thruster performance, voltage-current characteristics, and plume properties; but will also attempt to quantify the magnitude of the ionization and acceleration zones upstream shifting as a function of increased background pressure.

  1. Simple catalytic cell for restoring He leak detector sensitivity on vacuum systems with high D2 backgrounds

    International Nuclear Information System (INIS)

    Busath, J.; Chiu, H.K.

    1998-12-01

    The DIII-D National Fusion Facility at General Atomics focuses on plasma physics and fusion energy science. The DIII-D tokamak is a 35 m 3 toroidal vacuum vessel with over 200 ports for diagnostic instrumentation, cryogenics, microwave heating, and four large neutral beam injectors. Maintaining vacuum in the 10 -8 Torr range is crucial for producing high performance plasma discharges. He leak checking the DIII-D tokamak and the neutral beamlines has historically been difficult. D 2 is used as the fuel gas in most plasma discharges and neutral beams. After plasma operations, D 2 out-gassing from the torus walls and internal beamline components can exceed 10 -4 std cc/s. The mass of the D 2 molecule (4.028 u) is indistinguishable from that of the He atom (4.003 u) to a standard mass spectrometer leak detector. High levels of D 2 reduce leak detector sensitivity and effectively mask the He trace gas signal rendering normal leak checking techniques ineffective. A simple apparatus was developed at GA to address these problems. It consists of a palladium based catalyst cell and associated valves and piping placed in series with the leak detector. This reduces the D 2 throughput by a factor greater than 10,000, restoring leak detector sensitivity. This paper will briefly discuss the development of the cell, the physical processes involved, the tests performed to quantify and optimize the processes, and the operational results at DIII-D

  2. Denaturing high-performance liquid chromatography mutation analysis in patients with reduced Protein S levels

    DEFF Research Database (Denmark)

    Bathum, Lise; Münster, Anna-Marie; Nybo, Mads

    2008-01-01

    diagnosis and risk estimation. The aim was to design a high-throughput genetic analysis based on denaturing high-performance liquid chromatography to identify sequence variations in the gene coding for Protein S. PATIENTS: In total, 55 patients referred to the Section of Thrombosis and Haemostasis, Odense......BACKGROUND: Patients with congenital Protein S deficiency have increased risk of venous thromboembolism. However, Protein S levels show large intra-individual variation and the biochemical assays have low accuracy and a high interlaboratory variability. Genetic analysis might aid in a more precise......, giving a precise diagnosis and subsequently a better risk estimation....

  3. Overview: Defense high-level waste technology program

    International Nuclear Information System (INIS)

    Shupe, M.W.; Turner, D.A.

    1987-01-01

    Defense high-level waste generated by atomic energy defense activities is stored on an interim basis at three U.S. Department of Energy (DOE) operating locations; the Savannah River Plant in South Carolina, the Hanford Site in Washington, and the Idaho National Engineering Laboratory in Idaho. Responsibility for the permanent disposal of this waste resides with DOE's Office of Defense Waste and Transportation Management. The objective of the Defense High-Level Wast Technology Program is to develop the technology for ending interim storage and achieving permanent disposal of all U.S. defense high-level waste. New and readily retrievable high-level waste are immobilized for disposal in a geologic repository. Other high-level waste will be stabilized in-place if, after completion of the National Environmental Policy Act (NEPA) process, it is determined, on a site-specific basis, that this option is safe, cost effective and environmentally sound. The immediate program focus is on implementing the waste disposal strategy selected in compliance with the NEPA process at Savannah River, while continuing progress toward development of final waste disposal strategies at Hanford and Idaho. This paper presents an overview of the technology development program which supports these waste management activities and an assessment of the impact that recent and anticipated legal and institutional developments are expected to have on the program

  4. Teaching Evolution in New Jersey Public High Schools: Examining the Influence of Personal Belief and Religious Background on Teaching Practices

    Science.gov (United States)

    Smith, Carlen

    2010-01-01

    The purpose of this study was to determine relationships between New Jersey biology teachers' personal characteristics and religious backgrounds and the time spent and approach to teaching evolution. The research instrument chosen was a cross-sectional survey. Survey questions were presented in various forms: fill in, single response, Likert…

  5. HLA-DRB1 Analysis Identified a Genetically Unique Subset within Rheumatoid Arthritis and Distinct Genetic Background of Rheumatoid Factor Levels from Anticyclic Citrullinated Peptide Antibodies.

    Science.gov (United States)

    Hiwa, Ryosuke; Ikari, Katsunori; Ohmura, Koichiro; Nakabo, Shuichiro; Matsuo, Keitaro; Saji, Hiroh; Yurugi, Kimiko; Miura, Yasuo; Maekawa, Taira; Taniguchi, Atsuo; Yamanaka, Hisashi; Matsuda, Fumihiko; Mimori, Tsuneyo; Terao, Chikashi

    2018-04-01

    HLA-DRB1 is the most important locus associated with rheumatoid arthritis (RA) and anticitrullinated protein antibodies (ACPA). However, fluctuations of rheumatoid factor (RF) over the disease course have made it difficult to define fine subgroups according to consistent RF positivity for the analyses of genetic background and the levels of RF. A total of 2873 patients with RA and 2008 healthy controls were recruited. We genotyped HLA-DRB1 alleles for the participants and collected consecutive data of RF in the case subjects. In addition to RF+ and RF- subsets, we classified the RF+ subjects into group 1 (constant RF+) and group 2 (seroconversion). We compared HLA-DRB1 alleles between the RA subsets and controls and performed linear regression analysis to identify HLA-DRB1 alleles associated with maximal RF levels. Omnibus tests were conducted to assess important amino acid positions. RF positivity was 88%, and 1372 and 970 RF+ subjects were classified into groups 1 and 2, respectively. RF+ and RF- showed similar genetic associations to ACPA+ and ACPA- RA, respectively. We found that shared epitope (SE) was more enriched in group 2 than 1, p = 2.0 × 10 -5 , and that amino acid position 11 showed a significant association between 1 and 2, p = 2.7 × 10 -5 . These associations were independent of ACPA positivity. SE showed a tendency to be negatively correlated with RF titer (p = 0.012). HLA-DRB1*09:01, which reduces ACPA titer, was not associated with RF levels (p = 0.70). The seroconversion group was shown to have distinct genetic characteristics. The genetic architecture of RF levels is different from that of ACPA.

  6. Exploring the MIS M2 glaciation occurring during a warm and high atmospheric CO2 Pliocene background climate

    Science.gov (United States)

    Tan, Ning; Ramstein, Gilles; Dumas, Christophe; Contoux, Camille; Ladant, Jean-Baptiste; Sepulchre, Pierre; Zhang, Zhongshi; De Schepper, Stijn

    2017-08-01

    Prior to the Northern Hemisphere glaciation around ∼2.7 Ma, a large global glaciation corresponding to a 20 to 60 m sea-level drop occurred during Marine Isotope Stage (MIS) M2 (3.312-3.264 Ma), interrupted the period of global warmth and high CO2 concentration (350-450 ppmv) of the mid Piacenzian. Unlike the late Quaternary glaciations, the M2 glaciation only lasted 50 kyrs and occurred under uncertain CO2 concentration (220-390 ppmv). The mechanisms causing the onset and termination of the M2 glaciation remain enigmatic, but a recent geological hypothesis suggests that the re-opening and closing of the shallow Central American Seaway (CAS) might have played a key role. In this article, thanks to a series of climate simulations carried out using a fully coupled Atmosphere Ocean General Circulation Model (GCM) and a dynamic ice sheet model, we show that re-opening of the shallow CAS helps precondition the low-latitude oceanic circulation and affects the related northward energy transport, but cannot alone explain the onset of the M2 glaciation. The presence of a shallow open CAS, together with favourable orbital parameters, 220 ppmv of CO2 concentration, and the related vegetation and ice sheet feedback, led to a global ice sheet build-up producing a global sea-level drop in the lowest range of proxy-derived estimates. More importantly, our results show that the simulated closure of the CAS has a negligible impact on the NH ice sheet melt and cannot explain the MIS M2 termination.

  7. Managing the nation's commercial high-level radioactive waste

    International Nuclear Information System (INIS)

    1985-03-01

    This report presents the findings and conclusions of OTA's analysis of Federal policy for the management of commercial high-level radioactive waste. It represents a major update and expansion of the Analysis presented to Congress in our summary report, Managing Commercial High-Level Radioactive Waste, published in April of 1982 (NWPA). This new report is intended to contribute to the implementation of NWPA, and in particular to Congressional review of three major documents that DOE will submit to the 99th Congress: a Mission Plan for the waste management program; a monitored retrievable storage (MRS) proposal; and a report on mechanisms for financing and managing the waste program. The assessment was originally focused on the ocean disposal of nuclear waste. OTA later broadened the study to include all aspects of high-level waste disposal. The major findings of the original analysis were published in OTA's 1982 summary report

  8. Techniques for the solidification of high-level wastes

    International Nuclear Information System (INIS)

    1977-01-01

    The problem of the long-term management of the high-level wastes from the reprocessing of irradiated nuclear fuel is receiving world-wide attention. While the majority of the waste solutions from the reprocessing of commercial fuels are currently being stored in stainless-steel tanks, increasing effort is being devoted to developing technology for the conversion of these wastes into solids. A number of full-scale solidification facilities are expected to come into operation in the next decade. The object of this report is to survey and compare all the work currently in progress on the techniques available for the solidification of high-level wastes. It will examine the high-level liquid wastes arising from the various processes currently under development or in operation, the advantages and disadvantages of each process for different types and quantities of waste solutions, the stages of development, the scale-up potential and flexibility of the processes

  9. Spent fuel and high-level radioactive waste storage

    International Nuclear Information System (INIS)

    Trigerman, S.

    1988-06-01

    The subject of spent fuel and high-level radioactive waste storage, is bibliographically reviewed. The review shows that in the majority of the countries, spent fuels and high-level radioactive wastes are planned to be stored for tens of years. Sites for final disposal of high-level radioactive wastes have not yet been found. A first final disposal facility is expected to come into operation in the United States of America by the year 2010. Other final disposal facilities are expected to come into operation in Germany, Sweden, Switzerland and Japan by the year 2020. Meanwhile , stress is placed upon the 'dry storage' method which is carried out successfully in a number of countries (Britain and France). In the United States of America spent fuels are stored in water pools while the 'dry storage' method is still being investigated. (Author)

  10. Production and properties of solidified high-level waste

    International Nuclear Information System (INIS)

    Brodersen, K.

    1980-08-01

    Available information on production and properties of solidified high-level waste are presented. The review includes literature up to the end of 1979. The feasibility of production of various types of solidified high-level wast is investigated. The main emphasis is on borosilicate glass but other options are also mentioned. The expected long-term behaviour of the materials are discussed on the basis of available results from laboratory experiments. Examples of the use of the information in safety analysis of disposal in salt formations are given. The work has been made on behalf of the Danish utilities investigation of the possibilities of disposal of high-level waste in salt domes in Jutland. (author)

  11. Translation of a High-Level Temporal Model into Lower Level Models: Impact of Modelling at Different Description Levels

    DEFF Research Database (Denmark)

    Kraft, Peter; Sørensen, Jens Otto

    2001-01-01

    given types of properties, and examine how descriptions on higher levels translate into descriptions on lower levels. Our example looks at temporal properties where the information is concerned with the existence in time. In a high level temporal model with information kept in a three-dimensional space...... the existences in time can be mapped precisely and consistently securing a consistent handling of the temporal properties. We translate the high level temporal model into an entity-relationship model, with the information in a two-dimensional graph, and finally we look at the translations into relational...... and other textual models. We also consider the aptness of models that include procedural mechanisms such as active and object databases...

  12. Research on high level radioactive waste repository seismic design criteria

    International Nuclear Information System (INIS)

    Jing Xu

    2012-01-01

    Review seismic hazard analysis principle and method in site suitable assessment process of Yucca Mountain Project, and seismic design criteria and seismic design basis in primary design process. Demonstrated spatial character of seismic hazard by calculated regional seismic hazard map. Contrasted different level seismic design basis to show their differences and relation. Discussed seismic design criteria for preclosure phrase of high level waste repository and preference goal under beyond design basis ground motion. (author)

  13. An Exploratory Study of the Effects of Mindfulness on Perceived Levels of Stress among school-children from lower socioeconomic backgrounds.

    Directory of Open Access Journals (Sweden)

    Elizabeth Costello

    2014-11-01

    Full Text Available Children from lower socioeconomic backgrounds are at increased risk of experiencing stress and associated social-emotional difficulties and behavioural problems, which can undermine academic performance and lead to school drop-out. Previous studies investigating the effects of mindfulness have evidenced positive outcomes among children pertaining to enhanced well-being, school-based competence and decreased levels of stress and anxiety. However, these studies have typically examined teacher’s perceptions of change or quantitative outcomes without consideration of children’s experiences. The present study employs an interpretative qualitative approach to gain a greater understanding of children’s experiences of mindfulness in dealing with stress. A 5-week school-based mindfulness program was performed with 63 primary school children at risk of social exclusion in education. Interviews were undertaken with 16 children and 2 teachers. Thematic analysis identified five key themes labelled conceptualisation of stress, awareness, self-regulation, classroom regulations and addressing future stress. Quantitative measures of children’s perceived stress levels evaluated at baseline and follow-up also revealed significant reductions post intervention. These findings offer support for the incorporation of mindfulness interventions into the school curriculum, as a means of empowering children to address stress in their lives and improving full participation in the education system.

  14. OCRWM Backgrounder, January 1987

    International Nuclear Information System (INIS)

    1987-01-01

    The Nuclear Waste Policy Act of 1982 (NWPA) assigns to the US Department of Energy (DOE) responsibility for developing a system to safely and economically transport spent nuclear fuel and high-level radioactive waste from various storage sites to geologic repositories or other facilities that constitute elements of the waste management program. This transportation system will evolve from technologies and capabilities already developed. Shipments of spent fuel to a monitored retrievable storage (MRS) facility could begin as early as 1996 if Congress authorizes its construction. Shipments of spent fuel to a geologic repository are scheduled to begin in 1998. The backgrounder provides an overview of DOE's cask development program. Transportation casks are a major element in the DOE nuclear waste transportation system because they are the primary protection against any potential radiation exposure to the public and transportation workers in the event an accident occurs

  15. High level radioactive waste management facility design criteria

    International Nuclear Information System (INIS)

    Sheikh, N.A.; Salaymeh, S.R.

    1993-01-01

    This paper discusses the engineering systems for the structural design of the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS). At the DWPF, high level radioactive liquids will be mixed with glass particles and heated in a melter. This molten glass will then be poured into stainless steel canisters where it will harden. This process will transform the high level waste into a more stable, manageable substance. This paper discuss the structural design requirements for this unique one of a kind facility. A special emphasis will be concentrated on the design criteria pertaining to earthquake, wind and tornado, and flooding

  16. Development of technical information database for high level waste disposal

    International Nuclear Information System (INIS)

    Kudo, Koji; Takada, Susumu; Kawanishi, Motoi

    2005-01-01

    A concept design of the high level waste disposal information database and the disposal technologies information database are explained. The high level waste disposal information database contains information on technologies, waste, management and rules, R and D, each step of disposal site selection, characteristics of sites, demonstration of disposal technology, design of disposal site, application for disposal permit, construction of disposal site, operation and closing. Construction of the disposal technologies information system and the geological disposal technologies information system is described. The screen image of the geological disposal technologies information system is shown. User is able to search the full text retrieval and attribute retrieval in the image. (S.Y. )

  17. High-Level Waste (HLW) Feed Process Control Strategy

    International Nuclear Information System (INIS)

    STAEHR, T.W.

    2000-01-01

    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system

  18. Final report on cermet high-level waste forms

    International Nuclear Information System (INIS)

    Kobisk, E.H.; Quinby, T.C.; Aaron, W.S.

    1981-08-01

    Cermets are being developed as an alternate method for the fixation of defense and commercial high level radioactive waste in a terminal disposal form. Following initial feasibility assessments of this waste form, consisting of ceramic particles dispersed in an iron-nickel base alloy, significantly improved processing methods were developed. The characterization of cermets has continued through property determinations on samples prepared by various methods from a variety of simulated and actual high-level wastes. This report describes the status of development of the cermet waste form as it has evolved since 1977. 6 tables, 18 figures

  19. Managing the high level waste nuclear regulatory commission licensing process

    International Nuclear Information System (INIS)

    Baskin, K.P.

    1992-01-01

    This paper reports that the process for obtaining Nuclear Regulatory Commission permits for the high level waste storage facility is basically the same process commercial nuclear power plants followed to obtain construction permits and operating licenses for their facilities. Therefore, the experience from licensing commercial reactors can be applied to the high level waste facility. Proper management of the licensing process will be the key to the successful project. The management of the licensing process was categorized into four areas as follows: responsibility, organization, communication and documentation. Drawing on experience from nuclear power plant licensing and basic management principles, the management requirement for successfully accomplishing the project goals are discussed

  20. Treatment technologies for non-high-level wastes (USA)

    International Nuclear Information System (INIS)

    Cooley, C.R.; Clark, D.E.

    1976-06-01

    Non-high-level waste arising from operations at nuclear reactors, fuel fabrication facilities, and reprocessing facilities can be treated using one of several technical alternatives prior to storage. Each alternative and the associated experience and status of development are summarized. The technology for treating non-high-level wastes is generally available for industrial use. Improved techniques applicable to the commercial nuclear fuel cycle are being developed and demonstrated to reduce the volume of waste and to immobilize it for storage. 36 figures, 59 references