WorldWideScience

Sample records for radiation tolerance

  1. Commercialization of radiation tolerant camera

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Choi, Young Soo; Kim, Sun Ku; Lee, Jong Min; Cha, Bung Hun; Lee, Nam Ho; Byun, Eiy Gyo; Yoo, Seun Wook; Choi, Bum Ki; Yoon, Sung Up; Kim, Hyun Gun; Sin, Jeong Hun; So, Suk Il

    1999-12-01

    In this project, radiation tolerant camera which tolerates 10{sup 6} - 10{sup 8} rad total dose is developed. In order to develop radiation tolerant camera, radiation effect of camera components was examined and evaluated, and camera configuration was studied. By the result of evaluation, the components were decided and design was performed. Vidicon tube was selected to use by image sensor and non-browning optics and camera driving circuit were applied. The controller needed for CCTV camera system, lens, light, pan/tilt controller, was designed by the concept of remote control. And two type of radiation tolerant camera were fabricated consider to use in underwater environment or normal environment. (author)

  2. Commercialization of radiation tolerant camera

    International Nuclear Information System (INIS)

    Lee, Yong Bum; Choi, Young Soo; Kim, Sun Ku; Lee, Jong Min; Cha, Bung Hun; Lee, Nam Ho; Byun, Eiy Gyo; Yoo, Seun Wook; Choi, Bum Ki; Yoon, Sung Up; Kim, Hyun Gun; Sin, Jeong Hun; So, Suk Il

    1999-12-01

    In this project, radiation tolerant camera which tolerates 10 6 - 10 8 rad total dose is developed. In order to develop radiation tolerant camera, radiation effect of camera components was examined and evaluated, and camera configuration was studied. By the result of evaluation, the components were decided and design was performed. Vidicon tube was selected to use by image sensor and non-browning optics and camera driving circuit were applied. The controller needed for CCTV camera system, lens, light, pan/tilt controller, was designed by the concept of remote control. And two type of radiation tolerant camera were fabricated consider to use in underwater environment or normal environment. (author)

  3. Immune tolerance in radiation chimeras

    International Nuclear Information System (INIS)

    Awaya, Kazuhiko; Kuniki, Hiromichi; Neki, Miyuki

    1978-01-01

    Establishment of immune tolerance in radiation chimeras and the mechanism of maintaining it were discussed from certain points. Semiallogeneic radiation chimeras are mostly of long-living, and the hematopoietic organ of this individual consists mainly of the cells derived from the marrow donor, i. e., F 1 -type cells. F 1 -type lymphocytes can distinguish parental strain cells from themselves. In these chimeras, a F 1 -skin graft maintains to be fresh as long as the host is alive, showing immune tolerance effective through its life. In establishment and maintenance of this immune tolerance, the suppressing mechanism of host-type or F 1 -type seems to be involved. The allogeneic radiation chimera has very poor long-survival rate compared with that of the semiallogeneic radiation chimera. To raise this survival rate, efforts are now being made from the immunological point of view. (Ueda, J.)

  4. Radiation tolerance of amorphous semiconductors

    International Nuclear Information System (INIS)

    Nicolaides, R.V.; DeFeo, S.; Doremus, L.W.

    1976-01-01

    In an attempt to determine the threshold radiation damage in amorphous semiconductors, radiation tests were performed on amorphous semiconductor thin film materials and on threshold and memory devices. The influence of flash x-rays and neutron radiation upon the switching voltages, on- and off-state characteristics, dielectric response, optical transmission, absorption band edge and photoconductivity were measured prior to, during and following irradiation. These extensive tests showed the high radiation tolerance of amorphous semiconductor materials. Electrical and optical properties, other than photoconductivity, have a neutron radiation tolerance threshold above 10 17 nvt in the steady state and 10 14 nvt in short (50 μsec to 16 msec) pulses. Photoconductivity increases by 1 1 / 2 orders of magnitude at the level of 10 14 nvt (short pulses of 50 μsec). Super flash x-rays up to 5000 rads (Si), 20 nsec, do not initiate switching in off-state samples which are voltage biased up to 90 percent of the threshold voltage. Both memory and threshold amorphous devices are capable of switching on and off during nuclear radiation transients at least as high as 2 x 10 14 nvt in 50 μsec pulses

  5. State of art in radiation tolerant camera

    Energy Technology Data Exchange (ETDEWEB)

    Choi; Young Soo; Kim, Seong Ho; Cho, Jae Wan; Kim, Chang Hoi; Seo, Young Chil

    2002-02-01

    Working in radiation environment such as nuclear power plant, RI facility, nuclear fuel fabrication facility, medical center has to be considered radiation exposure, and we can implement these job by remote observation and operation. However the camera used for general industry is weakened at radiation, so radiation-tolerant camera is needed for radiation environment. The application of radiation-tolerant camera system is nuclear industry, radio-active medical, aerospace, and so on. Specially nuclear industry, the demand is continuous in the inspection of nuclear boiler, exchange of pellet, inspection of nuclear waste. In the nuclear developed countries have been an effort to develop radiation-tolerant cameras. Now they have many kinds of radiation-tolerant cameras which can tolerate to 10{sup 6}-10{sup 8} rad total dose. In this report, we examine into the state-of-art about radiation-tolerant cameras, and analyze these technology. We want to grow up the concern of developing radiation-tolerant camera by this paper, and upgrade the level of domestic technology.

  6. Radiation tolerant power converter controls

    CERN Document Server

    Todd, B; King, Q; Uznanski, S

    2012-01-01

    The Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN) is the world's most powerful particle collider. The LHC has several thousand magnets, both warm and super-conducting, which are supplied with current by power converters. Each converter is controlled by a purpose-built electronic module called a Function Generator Controller (FGC). The FGC allows remote control of the power converter and forms the central part of a closed-loop control system where the power converter voltage is set, based on the converter output current and magnet-circuit characteristics. Some power converters and FGCs are located in areas which are exposed to beam-induced radiation. There are numerous radiation induced effects, some of which lead to a loss of control of the power converter, having a direct impact upon the accelerator's availability. Following the first long shut down (LS1), the LHC will be able to run with higher intensity beams and higher beam energy. This is expected to lead to signifi...

  7. Radiation tolerance of the vaginal mucosa

    International Nuclear Information System (INIS)

    Hintz, b.L.; Kagan, A.R.; Chan, P.; Gilbert, H.A.; Nussbaum, H.; Rao, A.R.; Wollin, M.

    1980-01-01

    Sixteen patients with cancer of the vagina that were controlled locally for a minimum of eighteen months after teletherpay (T) or brachytherapy (B) or both (T and B), were analyzed for radiation tolerance of the vaginal mucosa. The site of vaginal necrosis did not always coincide with the site of the tumor. The posterior wall appeared more vulnerable than the anterior or lateral walls. For the distal vaginal mucosa, necrosis requiring surgical intervention occurred following combined T and B, if summated rad exceeded9800. The upper vagina tolerated higher dosages. No patient surgery for upper vaginal necrosis even though summated (T and B) dosage up to 14,000 rad was applied. Placing radioactive needles on the surface of the vaginal cylinder with or without interstitial perincal needles should be avoided. Further accumulation of data is needed to define these vaginal mucosa tolerance limits more closely

  8. Orchid flowers tolerance to gamma-radiation

    International Nuclear Information System (INIS)

    Kikuchi, Olivia Kimiko

    2000-01-01

    Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.(author)

  9. Orchid flowers tolerance to gamma-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Olivia Kimiko E-mail: okikuchi@net.ipen.br

    2000-03-01

    Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.(author)

  10. Radiation-Tolerant Intelligent Memory Stack - RTIMS

    Science.gov (United States)

    Ng, Tak-kwong; Herath, Jeffrey A.

    2011-01-01

    This innovation provides reconfigurable circuitry and 2-Gb of error-corrected or 1-Gb of triple-redundant digital memory in a small package. RTIMS uses circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field-programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuits are stacked into a module of 42.7 42.7 13 mm. Triple module redundancy, current limiting, configuration scrubbing, and single- event function interrupt detection are employed to mitigate radiation effects. The novel self-scrubbing and single event functional interrupt (SEFI) detection allows a relatively soft FPGA to become radiation tolerant without external scrubbing and monitoring hardware

  11. Tolerance to gamma radiation in the marine heterotardigrade, Echiniscoides sigismundi

    DEFF Research Database (Denmark)

    Jönsson, K. Ingemar; Hygum, Thomas Lunde; Andersen, Kasper Nørgaard

    2016-01-01

    Tardigrades belong to the most radiation tolerant animals on Earth, as documented by a number of studies using both low-LET and high-LET ionizing radiation. Previous studies have focused on semi-terrestrial species, which are also very tolerant to desiccation. The predominant view on the reason...... for the high radiation tolerance among these semi-terrestrial species is that it relies on molecular mechanisms that evolved as adaptations for surviving dehydration. In this study we report the first study on radiation tolerance in a marine tardigrade, Echiniscoides sigismundi. Adult specimens in the hydrated...... that have high tolerance to both desiccation and radiation, supporting the hypothesis that radiation tolerance is a by-product of adaptive mechanisms to survive desiccation. More studies on radiation tolerance in tardigrade species adapted to permanently wet conditions, both marine and freshwater...

  12. Radiation therapy tolerance doses for treatment planning

    International Nuclear Information System (INIS)

    Lyman, J.T.

    1987-01-01

    To adequately plan acceptable dose distributions for radiation therapy treatments it is necessary to ensure that normal structures do not receive unacceptable doses. Acceptable doses are generally those that are below a stated tolerance dose for development of some level of complication. To support the work sponsored by the National Cancer Institute, data for the tolerance of normal tissues or organs to low-LET radiation has been compiled from a number of sources. These tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD 5 ) or 50% (TD 50 ) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represent doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same end point. 20 refs., 1 fig., 1 tab

  13. Tolerance of retroperitoneal structures to intraoperative radiation

    International Nuclear Information System (INIS)

    Sindelar, W.F.; Tepper, J.; Travis, E.L.; Terrill, R.

    1982-01-01

    In conjunction with the clinical development of intraoperative radiotherapy, a study was undertaken in dogs to define the tolerance of normal anatomic structures in the retroperitoneum to radiation delivered during operation. Twenty adult dogs were subjected to laparotomy and intraoperative 11 MeV electron irradiation in single doses ranging from 0.to 5000 rad. Animals were followed regularly with clinical observation, blood count, serum chemistries, pyelography, and angiography. Animals were sacrificed and autopsied at regular intervals up to 12 months following treatment to assess radiation-induced complications or tissue damage. Irradiation field in all dogs consisted of a 4 X 15 cm rectangle extending in the retroperitoneum from the level of the renal vessels to the bifurcation of aorta and vena cava. The field included aorta, vena cava, inferior portion of left kidney, and distal portion of left ureter. No complications or histologic changes occurred in any animal given doses of 2000 rad, with a follow-up in excess of 18 months. A dose of 3000 rad was well tolerated, except for left ureteral occlusion in one animal. Mild vascular fibrosis was present inthe aorta and vena cava, and significant ureteral fibrosis developed by six months after doses of 4000 or 5000 rad. All animals that received 5000 rad died of radiation-related complications, including ureteral obstruction and rectal perforation. It was concluded that major vessels tolerate intraoperative irradiation well up to and including 3000 rad and that no clinically significant vascular problems develop after 4000 and 5000 rad, although some fibrosis does occur. The ureter and kidney appear to be the most radiosensitive structures inthe retroperitoneum, showing progressive changes at 300 rad or greater and showing the potential for serious complications after doses of 4000 rad or more

  14. Radiation tolerance of NPN bipolar technology with 30 GHz Ft

    International Nuclear Information System (INIS)

    Flament, O.; Synold, S.; Pontcharra, J. de; Niel, S.

    1999-01-01

    The ionizing dose and neutron radiation tolerance of Si QSA bipolar technology has been investigated. The transistors exhibit good radiation tolerance up to 100 krad and 5 10 13 n/cm 2 without any special fabrication steps to harden the technology to the studied effects. (authors)

  15. Radiation Tolerant, FPGA-based SmallSat Computer System

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this project is to mature the technology readiness of a radiation tolerant smallsat computer system for a subsequent orbital flight demonstration. The...

  16. Radiation Tolerant Software Defined Video Processor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — MaXentric's is proposing a radiation tolerant Software Define Video Processor, codenamed SDVP, for the problem of advanced motion imaging in the space environment....

  17. Radiation tolerance of the cervical spinal cord

    International Nuclear Information System (INIS)

    McCunniff, A.J.; Liang, M.J.

    1989-01-01

    The incidence of permanent injury to the spinal cord as a complication of radiation therapy generally correlates positively with total radiation dosage. However, several reports in the literature have indicated that fraction size is also an important factor in the development or nondevelopment of late injuries in normal tissue. To determine the effect of fraction size on the incidence of radiation-induced spinal cord injuries, we reviewed 144 cases of head and neck cancer treated at our institution between 1971 and 1980 with radiation greater than 5600 cGy to a portion of the cervical spinal cord. Most of these patients received greater than or equal to 6000 cGy, with fraction sizes ranging from 133 cGy to 200 cGy. Fifty-three of the 144 patients have been followed up for 2 years or more. Nearly half of these (26 patients) received greater than 6000 cGy with fraction sizes of 133 cGy to 180 cGy. Only 1 of the 53 (1.9%) has sustained permanent spinal cord injury; 20 months after completion of radiation treatments he developed Brown-Sequard syndrome. Our experience suggests that radiation injuries to the spinal cord correlate not only with total radiation dosage, but also with fraction size; low fraction sizes appear to decrease the incidence of such injuries

  18. Measurement tolerance analysis of solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Cimo, J.; Maderkova, L.; Horak, J.; Igaz, D.; Pasztorova, S. [Department of Biomereorlogy and Hydrology, Slovak Agriculture University, Nitra (Slovakia)

    2012-07-01

    Solar radiant energy is bane and almost the only one source of heat for Earth 's surface and for atmosphere, and almost the only one source of energy for physical processes. Solar energy is one of the most available and the most ecological energy source. Currently the firm Kipp and Zonen belongs to prominent producer of sensors for measuring of global radiation. These sensors are the most used in our country and also in network of meteorological measurements of WMO. Therefore the two types of measuring sensors for global radiation (pyranometer PMP6, CMP 11) in comparison with calculation method Savin-Angstrom are analysed. (author)

  19. A high precision radiation-tolerant LVDT conditioning module

    CERN Document Server

    Masi, A; Losito, R; Peronnard, P; Secondo, R; Spiezia, G

    2014-01-01

    Linear variable differential transformer (LVDT) position sensors are widely used in particle accelerators and nuclear plants, thanks to their properties of contact-less sensing, radiation tolerance, infinite resolution, good linearity and cost efficiency. Many applications require high reading accuracy, even in environments with high radiation levels, where the conditioning electronics must be located several hundred meters away from the sensor. Sometimes even at long distances the conditioning module is still exposed to ionizing radiation. Standard off-the-shelf electronic conditioning modules offer limited performances in terms of reading accuracy and long term stability already with short cables. A radiation tolerant stand-alone LVDT conditioning module has been developed using Commercial Off-The-Shelf (COTS) components. The reading of the sensor output voltages is based on a sine-fit algorithm digitally implemented on an FPGA ensuring few micrometers reading accuracy even with low signal-to-noise ratios. ...

  20. Studying Radiation Tolerant ICs for LHC

    CERN Multimedia

    Faccio, F; Snoeys, W; Campbell, M; Casas-cubillos, J; Gomes, P

    2002-01-01

    %title\\\\ \\\\In the recent years, intensive work has been carried out on the development of custom ICs for the readout electronics for LHC experiments. As far as radiation hardness is concerned, attention has been focussed on high total dose applications, mainly for the tracker systems. The dose foreseen in this inner region is estimated to be higher than 1~Mrad/year. In the framework of R&D projects (RD-9 and RD-20) and in the ATLAS and CMS experiments, the study of different radiation hard processes has been pursued and good contacts with the manufacturers have been established. The results of these studies have been discussed during the Microelectronics User Group (MUG) rad-hard meetings, and now some HEP groups are working to develop radiation hard ICs for the LHC experiments on some of the available rad-hard processes.\\\\ \\\\In addition, a lot of the standard commercial electronic components and ASICs which are planned to be installed near the LHC machine and in the detectors will receive total doses in ...

  1. Radiation tolerant design - theory and practice for proximity sensing

    International Nuclear Information System (INIS)

    Sharp, R.E.; Pater, S.L.; Cook, J.

    1999-01-01

    This paper provides a description of the radiation tolerant design process used to develop a range of proximity detectors with guaranteed total dose lifetime. It also describes some of the applications in which the detectors are being used and the benefits gained by plant operators. (authors)

  2. Improved radiation tolerance of MAPS using a depleted epitaxial layer

    International Nuclear Information System (INIS)

    Dorokhov, A.; Bertolone, G.; Baudot, J.; Brogna, A.S.; Colledani, C.; Claus, G.; De Masi, R.; Deveaux, M.; Doziere, G.; Dulinski, W.; Fontaine, J.-C.; Goffe, M.; Himmi, A.; Hu-Guo, Ch.; Jaaskelainen, K.; Koziel, M.; Morel, F.; Santos, C.; Specht, M.; Valin, I.

    2010-01-01

    Tracking performance of Monolithic Active Pixel Sensors (MAPS) developed at IPHC (Turchetta, et al., 2001) have been extensively studied (Winter, et al., 2001; Gornushkin, et al., 2002) . Numerous sensor prototypes, called MIMOSA, were fabricated and tested since 1999 in order to optimise the charge collection efficiency and power dissipation, to minimise the noise and to increase the readout speed. The radiation tolerance was also investigated. The highest fluence tolerable for a 10μm pitch device was found to be ∼10 13 n eq /cm 2 , while it was only 2x10 12 n eq /cm 2 for a 20μm pitch device. The purpose of this paper is to show that the tolerance to non-ionising radiation may be extended up to O(10 14 ) n eq /cm 2 . This goal relies on a fabrication process featuring a 15μm thin, high resistivity (∼1kΩcm) epitaxial layer. A sensor prototype (MIMOSA-25) was fabricated in this process to explore its detection performance. The depletion depth of the epitaxial layer at standard CMOS voltages ( 13 n eq /cm 2 ), making evidence of a significant extension of the radiation tolerance limits of MAPS.

  3. Normal tissue tolerance to external beam radiation therapy: The stomach

    International Nuclear Information System (INIS)

    Oberdiac, P.; Mineur, L.

    2010-01-01

    In the following article, we will discuss general issues relating to acute and late gastric's radiation toxicities. The tolerance of the stomach to complete or partial organ irradiation is more un-appreciated than for most other organs. We consulted the Medline database via PubMed and used the key words gastric - radiotherapy - toxicity. Currently, 60 Gy or less is prescribed in gastric radiation therapy. Acute clinical toxicity symptoms are predominantly nausea and vomiting. Although there is a general agreement that the whole stomach tolerance is for doses of 40 to 45 Gy without unacceptable complication, it is well established that a stomach dose of 35 Gy increases the risk of ulcer complications. (authors)

  4. Normal tissue tolerance to external beam radiation therapy: Adult bone

    International Nuclear Information System (INIS)

    Sargos, P.; Mamou, N.; Dejean, C.; Henriques de Figueiredo, B.; Kantor, G.; Huchet, A.; Italiano, A.

    2010-01-01

    Radiation tolerance for bone tissue has been mostly evaluated with regard to bone fracture. Main circumstances are mandibula osteoradionecrosis, hip and costal fracture, and patent or radiologic fractures in the treated volume. After radiation therapy of bone metastasis, the analysis of related radiation fracture is difficult to individualize from a pathologic fracture. Frequency of clinical fracture is less than 5% in the large series or cohorts and is probably under-evaluated for the asymptomatic lesions. Women older than 50 years and with osteoporosis are probably the main population at risk. Dose-effect relations are difficult to qualify in older series. Recent models evaluating radiations toxicity on diaphysa suggest an important risk after 60 Gy, for high dose-fraction and for a large volume. (authors)

  5. A high precision radiation-tolerant LVDT conditioning module

    Energy Technology Data Exchange (ETDEWEB)

    Masi, A. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Danzeca, S. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); IES, F-34000 Montpellier (France); Losito, R.; Peronnard, P. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Secondo, R., E-mail: raffaello.secondo@cern.ch [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Spiezia, G. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland)

    2014-05-01

    Linear variable differential transformer (LVDT) position sensors are widely used in particle accelerators and nuclear plants, thanks to their properties of contact-less sensing, radiation tolerance, infinite resolution, good linearity and cost efficiency. Many applications require high reading accuracy, even in environments with high radiation levels, where the conditioning electronics must be located several hundred meters away from the sensor. Sometimes even at long distances the conditioning module is still exposed to ionizing radiation. Standard off-the-shelf electronic conditioning modules offer limited performances in terms of reading accuracy and long term stability already with short cables. A radiation tolerant stand-alone LVDT conditioning module has been developed using Commercial Off-The-Shelf (COTS) components. The reading of the sensor output voltages is based on a sine-fit algorithm digitally implemented on an FPGA ensuring few micrometers reading accuracy even with low signal-to-noise ratios. The algorithm validation and board architecture are described. A full metrological characterization of the module is reported and radiation tests results are discussed.

  6. Tolerance, immunocompetence, and secondary disease in fully allogeneic radiation chimeras

    International Nuclear Information System (INIS)

    Rayfield, L.S.; Brent, L.

    1983-01-01

    The aim of this study was to ascertain the extent to which secondary disease and mortality in fully allogeneic chimeras (C57BL leads to CBA) is caused (if at all) by a delayed graft-versus-host reaction. Adult CBA males were thymectomized, irradiated, and reconstituted with T-lymphocyte-depleted C57BL or CBA bone marrow cells (BMC), followed three weeks after irradiation by implantation under the kidney capsule of thymic lobes from C57BL or CBA fetal or adult donors. These mice were observed for the development of secondary disease for periods in excess of 250 days, and they were examined at 5 weeks or 4 months for T lymphocyte reactivity and tolerance to alloantigens, using the cell-mediated lympholysis assay (CML). The following results were obtained. First, removal of T lymphocytes with anti-Thy 1 antibody and complement from allogeneic bone marrow did not prevent wasting and eventual death, although it prolonged the lifespan of mice substantially. Second, T lymphocytes generated from bone marrow-derived precursor cells became tolerant of the histocompatibility antigens of the thymus donor strain but remained normally reactive to third-party antigens. Third, allogeneic radiation chimeras did not survive as well as animals reconstituted with syngeneic cells, even when they were demonstrably tolerant in CML. Fourth, C57BL BMC maturing in a CBA host equipped with a C57BL thymus graft did not become tolerant of host antigens, indicating that extra-thymic tolerance does not occur in fully allogeneic--as opposed to semiallogeneic--chimeras. It is argued that the function of B lymphocytes and/or accessory cells is impaired in fully allogeneic radiation chimeras, and that the mortality observed was directly related to the resulting immunodeficiency. The relevance of the results described in this paper to clinical bone marrow transplantation is discussed

  7. Improved radiation tolerance of MAPS using a depleted epitaxial layer

    Energy Technology Data Exchange (ETDEWEB)

    Dorokhov, A., E-mail: Andrei.Dorokhov@IReS.in2p3.f [Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du loess, BP 28, 67037 Strasbourg (France); Bertolone, G.; Baudot, J.; Brogna, A.S.; Colledani, C.; Claus, G.; De Masi, R. [Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du loess, BP 28, 67037 Strasbourg (France); Deveaux, M. [Goethe-Universitaet Frankfurt am Main, Senckenberganlage 31, 60325 Frankfurt am Main (Germany); Doziere, G.; Dulinski, W. [Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du loess, BP 28, 67037 Strasbourg (France); Fontaine, J.-C. [Groupe de Recherche en Physique des Hautes Energies (GRPHE), Universite de Haute Alsace, 61, rue Albert Camus, 68093 Mulhouse (France); Goffe, M.; Himmi, A.; Hu-Guo, Ch.; Jaaskelainen, K.; Koziel, M.; Morel, F.; Santos, C.; Specht, M.; Valin, I. [Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du loess, BP 28, 67037 Strasbourg (France)

    2010-12-11

    Tracking performance of Monolithic Active Pixel Sensors (MAPS) developed at IPHC (Turchetta, et al., 2001) have been extensively studied (Winter, et al., 2001; Gornushkin, et al., 2002) . Numerous sensor prototypes, called MIMOSA, were fabricated and tested since 1999 in order to optimise the charge collection efficiency and power dissipation, to minimise the noise and to increase the readout speed. The radiation tolerance was also investigated. The highest fluence tolerable for a 10{mu}m pitch device was found to be {approx}10{sup 13}n{sub eq}/cm{sup 2}, while it was only 2x10{sup 12}n{sub eq}/cm{sup 2} for a 20{mu}m pitch device. The purpose of this paper is to show that the tolerance to non-ionising radiation may be extended up to O(10{sup 14}) n{sub eq}/cm{sup 2}. This goal relies on a fabrication process featuring a 15{mu}m thin, high resistivity ({approx}1k{Omega}cm) epitaxial layer. A sensor prototype (MIMOSA-25) was fabricated in this process to explore its detection performance. The depletion depth of the epitaxial layer at standard CMOS voltages (<5V) is similar to the layer thickness. Measurements with m.i.p.s show that the charge collected in the seed pixel is at least twice larger for the depleted epitaxial layer than for the undepleted one, translating into a signal-to-noise ratio (SNR) of {approx}50. Tests after irradiation have shown that this excellent performance is maintained up to the highest fluence considered (3x10{sup 13}n{sub eq}/cm{sup 2}), making evidence of a significant extension of the radiation tolerance limits of MAPS.

  8. A radiation-tolerant electronic readout system for portal imaging

    Science.gov (United States)

    Östling, J.; Brahme, A.; Danielsson, M.; Iacobaeus, C.; Peskov, V.

    2004-06-01

    A new electronic portal imaging device, EPID, is under development at the Karolinska Institutet and the Royal Institute of Technology. Due to considerable demands on radiation tolerance in the radiotherapy environment, a dedicated electronic readout system has been designed. The most interesting aspect of the readout system is that it allows to read out ˜1000 pixels in parallel, with all electronics placed outside the radiation beam—making the detector more radiation resistant. In this work we are presenting the function of a small prototype (6×100 pixels) of the electronic readout board that has been tested. Tests were made with continuous X-rays (10-60 keV) and with α particles. The results show that, without using an optimised gas mixture and with an early prototype only, the electronic readout system still works very well.

  9. Radiation-Tolerance Assessment of a Redundant Wireless Device

    Science.gov (United States)

    Huang, Q.; Jiang, J.

    2018-01-01

    This paper presents a method to evaluate radiation-tolerance without physical tests for a commercial off-the-shelf (COTS)-based monitoring device for high level radiation fields, such as those found in post-accident conditions in a nuclear power plant (NPP). This paper specifically describes the analysis of radiation environment in a severe accident, radiation damages in electronics, and the redundant solution used to prolong the life of the system, as well as the evaluation method for radiation protection and the analysis method of system reliability. As a case study, a wireless monitoring device with redundant and diversified channels is evaluated by using the developed method. The study results and system assessment data show that, under the given radiation condition, performance of the redundant device is more reliable and more robust than those non-redundant devices. The developed redundant wireless monitoring device is therefore able to apply in those conditions (up to 10 M Rad (Si)) during a severe accident in a NPP.

  10. Reliability and radiation tolerance of robots for nuclear applications

    Energy Technology Data Exchange (ETDEWEB)

    Lauridsen, K [Risoe National Lab. (Denmark); Decreton, M [SCK.CEN (Belgium); Seifert, C C [Siemens AG (Germany); Sharp, R [AEA Technology (United Kingdom)

    1996-10-01

    The reliability of a robot for nuclear applications will be affected by environmental factors such as dust, water, vibrations, heat, and, in particular, ionising radiation. The present report describes the work carried out in a project addressing the reliability and radiation tolerance of such robots. A widely representative range of components and materials has been radiation tested and the test results have been collated in a database along with data provided by the participants from earlier work and data acquired from other sources. A radiation effects guide has been written for the use by designers of electronic equipment for robots. A generic reliability model has been set up together with generic failure strategies, forming the basis for specific reliability modelling carried out in other projects. Modelling tools have been examined and developed for the prediction of the performance of electronic circuits subjected to radiation. Reports have been produced dealing with the prediction and detection of upcoming failures in electronic systems. Operational experience from the use of robots in radiation work in various contexts has been compiled in a report, and another report has been written on cost/benefit considerations about the use of robots. Also the possible impact of robots on the safety of the surrounding plant has been considered and reported. (au) 16 ills., 236 refs.

  11. Reliability and radiation tolerance of robots for nuclear applications

    International Nuclear Information System (INIS)

    Lauridsen, K.; Decreton, M.; Seifert, C.C.; Sharp, R.

    1996-10-01

    The reliability of a robot for nuclear applications will be affected by environmental factors such as dust, water, vibrations, heat, and, in particular, ionising radiation. The present report describes the work carried out in a project addressing the reliability and radiation tolerance of such robots. A widely representative range of components and materials has been radiation tested and the test results have been collated in a database along with data provided by the participants from earlier work and data acquired from other sources. A radiation effects guide has been written for the use by designers of electronic equipment for robots. A generic reliability model has been set up together with generic failure strategies, forming the basis for specific reliability modelling carried out in other projects. Modelling tools have been examined and developed for the prediction of the performance of electronic circuits subjected to radiation. Reports have been produced dealing with the prediction and detection of upcoming failures in electronic systems. Operational experience from the use of robots in radiation work in various contexts has been compiled in a report, and another report has been written on cost/benefit considerations about the use of robots. Also the possible impact of robots on the safety of the surrounding plant has been considered and reported. (au) 16 ills., 236 refs

  12. Normal tissue tolerance to external beam radiation therapy: Esophagus

    International Nuclear Information System (INIS)

    Bera, G.; Pointreau, Y.; Denis, F.; Dupuis, O.; Orain, I.; Crehange, G.

    2010-01-01

    The esophagus is a musculo-membranous tube through which food passes from the pharynx to the stomach. Due to its anatomical location, it can be exposed to ionizing radiation in many external radiotherapy indications. Radiation-induced esophageal mucositis is clinically revealed by dysphagia and odynophagia, and usually begins 3 to 4 weeks after the start of radiation treatment. With the rise of multimodality treatments (e.g., concurrent chemoradiotherapy, dose escalation and accelerated fractionation schemes), esophageal toxicity has become a significant dose-limiting issue. Understanding the predictive factors of esophageal injury may improve the optimal delivery of treatment plans. It may help to minimize the risks, hence increasing the therapeutic ratio. Based on a large literature review, our study describes both early and late radiation-induced esophageal injuries and highlights some of the predictive factors for cervical and thoracic esophagus toxicity. These clinical and dosimetric parameters are numerous but none is consensual. The large number of dosimetric parameters strengthens the need of an overall analysis of the dose/volume histograms. The data provided is insufficient to recommend their routine use to prevent radiation-induced esophagitis. Defining guidelines for the tolerance of the esophagus to ionizing radiation remains essential for a safe and efficient treatment. (authors)

  13. Radiation tolerance of the WorldFIP fieldbus interface

    CERN Document Server

    Wijnands, Thijs

    2006-01-01

    This paper summarises on radiation tests on the main components for the WorldFIP fieldbus interface. The chipset based on 0.6 \\mu­m technology has a total dose tolerance of 100 Gy (Co-60) and in standalone mode, no functional interrupts from single events have been observed during proton irradiation (60 MeV). The chipset based on 0.5 \\mu­m technology has a total dose tolerance of 150 Gy (Co-60) but shows a sharp increase in the single event cross section after a dose of 70 Gy. Finally, it was found that the chipset based on 0.5 \\mu­m technology operates reliable in standalone mode in a magnetic field up to 4.6 kGauss.

  14. VCSEL-based radiation tolerant optical data links

    CERN Document Server

    Gregor, I M; Dowell, J; Jovanovic, P; Kootz, A; Mahout, G; Mandic, I; Weidberg, T

    2000-01-01

    The Large Hadron Collider (LHC) will become operational in 2005 at The European Laboratory for Particle Physics (CERN). The LHC will be the highest energy proton-proton collider in the world. One of the electronic particle detectors which will operate at the LHC is called ATLAS. The environment for electronics placed within ATLAS is extremely hostile due to the high levels of radiation and the general lack of access to components during the expected 10 year lifetime of the experiment. It is planned to use custom radiation tolerant VCSEL- based optical links to transfer data from the ATLAS inner detector to remote data acquisition electronics. A low mass, non-magnetic and radiation tolerant VCSEL packaging has been developed for the most hostile region in the center of ATLAS where the inner detector is located. The performance of the package is reported on. Qualification tests of commercial VCSELs are also described. The VCSELs were irradiated with neutrons (up to 8.10/sup 14/ n(1 MeV)/cm/sup 2/) and annealing...

  15. Radiation tolerance of CVD diamond detectors for pions and protons

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F. E-mail: f.hartjes@nikhef.nl; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M

    2002-01-11

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/c pions and 24 GeV/c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal.

  16. Radiation tolerance of CVD diamond detectors for pions and protons

    Science.gov (United States)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L. S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J. L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R. J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.

    2002-01-01

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/ c pions and 24 GeV/ c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal.

  17. Radiation tolerance of CVD diamond detectors for pions and protons

    International Nuclear Information System (INIS)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.

    2002-01-01

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/c pions and 24 GeV/c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal

  18. Pulse height distribution and radiation tolerance of CVD diamond detectors

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dangelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F. E-mail: f.hartjes@nikhef.nl; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; D.Tromson,; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M.; Fenyvesi, A.; Molnar, J.; Sohler, D

    2000-06-01

    The paper reviews measurements of the radiation tolerance of CVD diamond for irradiation with 24 GeV/c protons, 300 MeV/c pions and 1 MeV neutrons. For proton and neutron irradiation, the measured charge signal spectrum is compared with the spectrum calculated by a model. Irradiation by particles causes radiation damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model shows that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. In addition, we observed after proton irradiation at the charge signal spectrum a decrease of the number of small signals. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal.

  19. Pulse height distribution and radiation tolerance of CVD diamond detectors

    CERN Document Server

    Adam, W; Bergonzo, P; Bertuccio, G; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredotti, C; Meier, D; Mishina, M; Moroni, L; Oh, A; Pan, L S; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Procario, M; Riester, J L; Roe, S; Rousseau, L; Rudge, A; Russ, J; Sala, S; Sampietro, M; Schnetzer, S R; Sciortino, S; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Tromson, D; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; White, C; Zeuner, W; Zöller, M; Fenyvesi, A; Molnár, J; Sohler, D

    2000-01-01

    The paper reviews measurements of the radiation tolerance of CVD diamond for irradiation with 24 GeV/c protons, 300 MeV/c pions and 1 MeV neutrons. For proton and neutron irradiation, the measured charge signal spectrum is compared with the spectrum calculated by a model. Irradiation by particles causes radiation damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model shows that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. In addition, we observed after proton irradiation at the charge signal spectrum a decrease of the number of small signals. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal. (11 refs).

  20. Pulse height distribution and radiation tolerance of CVD diamond detectors

    International Nuclear Information System (INIS)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dangelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; D.Tromson,; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M.; Fenyvesi, A.; Molnar, J.; Sohler, D.

    2000-01-01

    The paper reviews measurements of the radiation tolerance of CVD diamond for irradiation with 24 GeV/c protons, 300 MeV/c pions and 1 MeV neutrons. For proton and neutron irradiation, the measured charge signal spectrum is compared with the spectrum calculated by a model. Irradiation by particles causes radiation damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model shows that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. In addition, we observed after proton irradiation at the charge signal spectrum a decrease of the number of small signals. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal

  1. Selecting a radiation tolerant piezoelectric material for nuclear reactor applications

    Energy Technology Data Exchange (ETDEWEB)

    Parks, D. A.; Reinhardt, B. T.; Tittmann, B. R. [Department of Engineering Science and Mechanics, Penn State, University Park, PA 16803 (United States)

    2013-01-25

    Bringing systems for online monitoring of nuclear reactors to fruition has been delayed by the lack of suitable ultrasonic sensors. Recent work has demonstrated the capability of an AlN sensor to perform ultrasonic evaluation in an actual nuclear reactor. Although the AlN demonstrated sustainability, no loss in signal amplitude and d{sub 33} up to a fast and thermal neutron fluence of 1.85 Multiplication-Sign 1018 n/cm{sup 2} and 5.8 Multiplication-Sign 1018 n/cm{sup 2} respectively, no formal process to selecting a suitable sensor material was made. It would be ideal to use first principles approaches to somehow reduce each candidate piezoelectric material to a simple ranking showing directly which materials one should expect to be most radiation tolerant. However, the complexity of the problem makes such a ranking impractical and one must appeal to experimental observations. This should not be of any surprise to one whom is familiar with material science as most material properties are obtained in this manner. Therefore, this work adopts a similar approach, the mechanisms affecting radiation tolerance are discussed and a good engineering sense is used for material qualification of the candidate piezoelectric materials.

  2. Radiation Tolerant Design with 0.18-micron CMOS Technology

    CERN Document Server

    Chen, Li; Durdle , Nelson G.

    This thesis discusse s th e issues r elated to the us e of enclosed-gate layou t trans isto rs and guard rings in a 0.18 μ m CMOS technology in order to im prove the radiation tolerance of ASICs. The thin gate oxides of subm icron technologies ar e inherently m ore radiation tole rant tha n the thick er oxides present in less advanced technologies. Using a commercial deep subm icron technology to bu ild up radiation-ha rdened circuits introduces several advantages com pared to a dedicated radiation-ha rd technology, such as speed, power, area, stability, and expense. Som e novel aspects related to the use of encl osed-gate layout transist ors are presented in this th esis. A m odel to calculate the aspect ratio is introduced and verified. Some im portant electrica l par ameters of the tran sistors such as threshold voltage, leakage current, subthreshold slope, and transconducta nce are studied before and afte...

  3. Is the precision of human radiation tolerance estimates sufficient for radiation emergency management

    International Nuclear Information System (INIS)

    Lushbaugh, C.C.; Huebner, K.F.; Fry, S.A.; Ricks, R.C.

    1982-01-01

    Retrospective clinical evaluations of the deleterious consequences of accidental and therapeutic radiation exposures have provided working estimates of human radiation tolerance of variable accuracy. Their inaccuracy results from the fact that in accidents, where normal persons have been irradiated, doses have usually been unknown, whereas in radiotherapy, where doses are known precisely, the additivity of various diseases and cellular abnormalities upon final radiosensitivity remains largely unknown. Even so, from follow-up studies of radiation-accident victims, human radiation biology is not known to be qualitatively different from that of other animals and so the mechanisms of human radiation lethality are sufficiently understood to dictate therapeutic measures and suggest radiation dosage limits for their effectiveness for a few irradiated patients or where large populations are exposed under austere conditions. (author)

  4. Normal tissue tolerance to external beam radiation therapy: Peripheral nerves

    International Nuclear Information System (INIS)

    Henriques de Figueiredo, B.; Dejean, C.; Sargos, P.; Kantor, G.; Huchet, A.; Mamou, N.; Loiseau, H.

    2010-01-01

    Plexopathies and peripheral neuropathies appear progressively and with several years delay after radiotherapy. These lesions are observed principally after three clinical situations: supraclavicular and axillar irradiations for breast cancer, pelvic irradiations for various pathologies and limb irradiations for soft tissue sarcomas. Peripheral nerves and plexus (brachial and lumbosacral) are described as serial structures and are supposed to receive less than a given maximum dose linked to the occurrence of late injury. Literature data, mostly ancient, define the maximum tolerable dose to a threshold of 60 Gy and highlight also a great influence of fractionation and high fraction doses. For peripheral nerves, most frequent late effects are pain with significant differences of occurrence between 50 and 60 Gy. At last, associated pathologies (diabetes, vascular pathology, neuropathy) and associated treatments have probably to be taken into account as additional factors, which may increase the risk of these late radiation complications. (authors)

  5. Development of a self-maintenance radiation-tolerant robot

    International Nuclear Information System (INIS)

    Shimomura, Y.; Takahashi, H.; Tsuboi, Y.; Komatsu, K.

    2004-01-01

    The purpose of this research is to develop robot which dose not lose the function in radiation fields, and is able to get self-diagnosis and self-repair in the case of failure. The fundamental operation element and operational process algorithm are discussed. Utilizations of gas-micro electronics, which is easy to handle in comparison with vacuum field and to amplify with high speed by use of electron avalanche, are planed. The fundamental researches on radiation-tolerant robot which is not destructed by cosmic ray fields are carried out. The action of basic logic elements is ascertained. Self-repair type logic operations are considered. The self-repair type logic needs for to diagnosis abnormality of elements intellectually and repair by itself. Module failure diagnosis and repair plan technique based on qualitative inference are placed on the center of self-repair type logic. Self-maintenance robot can be actualized by modularization and divergence processing of diagnosis. (M. Suetake)

  6. Bulk Nanostructured FCC Steels With Enhanced Radiation Tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinghang; Hartwig, K. Ted; Allen, Todd; Yang, Yong

    2012-10-27

    The objective of this project is to increase radiation tolerance in austenitic steels through optimization of grain size and grain boundary (GB) characteristics. The focus will be on nanocrystalline austenitic Fe-Cr-Ni alloys with an fcc crystal structure. The long-term goal is to design and develop bulk nanostructured austenitic steels with enhanced void swelling resistance and substantial ductility, and to enhance their creep resistance at elevated temperatures via GB engineering. The combination of grain refinement and grain boundary engineering approaches allows us to tailor the material strength, ductility, and resistance to swelling by 1) changing the sink strength for point defects, 2) by increasing the nucleation barriers for bubble formation at GBs, and 3) by changing the precipitate distributions at boundaries. Compared to ferritic/martensitic steels, austenitic stainless steels (SS) possess good creep and fatigue resistance at elevated temperatures, and better toughness at low temperature. However, a major disadvantage of austenitic SS is that they are vulnerable to significant void swelling in nuclear reactors, especially at the temperatures and doses anticipated in the Advanced Burner Reactor. The lack of resistance to void swelling in austenitic alloys led to the switch to ferritic/martensitic steels as the preferred material for the fast reactor cladding application. Recently a type of austenitic stainless steel, HT-UPS, was developed at ORNL, and is expected to show enhanced void swelling resistance through the trapping of point defects at nanometersized carbides. Reducing the grain size and increasing the fraction of low energy grain boundaries should reduce the available radiation-produced point defects (due to the increased sink area of the grain boundaries), should make bubble nucleation at the boundaries less likely (by reducing the fraction of high-energy boundaries), and improve the strength and ductility under radiation by producing a higher

  7. The selection of radiation tolerant electrical/electronic components for gamma radiation environments in the nuclear power industry

    International Nuclear Information System (INIS)

    Garlick, D.R.

    1984-09-01

    This report briefly describes the mechanisms, units and effects of 1 MeV range gamma radiation on electrical/electronic components and materials. Information is tabulated on the gamma radiation tolerance of a wide range of components and materials. A radiation testing service, based at Harwell, is described. Lists of interested manufacturers and organisations are given. (author)

  8. Achieving Radiation Tolerance through Non-Equilibrium Grain Boundary Structures.

    Science.gov (United States)

    Vetterick, Gregory A; Gruber, Jacob; Suri, Pranav K; Baldwin, Jon K; Kirk, Marquis A; Baldo, Pete; Wang, Yong Q; Misra, Amit; Tucker, Garritt J; Taheri, Mitra L

    2017-09-25

    Many methods used to produce nanocrystalline (NC) materials leave behind non-equilibrium grain boundaries (GBs) containing excess free volume and higher energy than their equilibrium counterparts with identical 5 degrees of freedom. Since non-equilibrium GBs have increased amounts of both strain and free volume, these boundaries may act as more efficient sinks for the excess interstitials and vacancies produced in a material under irradiation as compared to equilibrium GBs. The relative sink strengths of equilibrium and non-equilibrium GBs were explored by comparing the behavior of annealed (equilibrium) and as-deposited (non-equilibrium) NC iron films on irradiation. These results were coupled with atomistic simulations to better reveal the underlying processes occurring on timescales too short to capture using in situ TEM. After irradiation, NC iron with non-equilibrium GBs contains both a smaller number density of defect clusters and a smaller average defect cluster size. Simulations showed that excess free volume contribute to a decreased survival rate of point defects in cascades occurring adjacent to the GB and that these boundaries undergo less dramatic changes in structure upon irradiation. These results suggest that non-equilibrium GBs act as more efficient sinks for defects and could be utilized to create more radiation tolerant materials in future.

  9. Nuclear Radiation Tolerance of Single Crystal Aluminum Nitride Ultrasonic Transducer

    Science.gov (United States)

    Reinhard, Brian; Tittmann, Bernhard R.; Suprock, Andrew

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models, (Rempe et al., 2011; Kazys et al., 2005). These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The irradiation is also supported by a multi-National Laboratory collaboration funded by the Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation (NEET ASI) program. The results from this irradiation, which started in February 2014, offer the potential to enable the development of novel radiation tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. Hence, results from this irradiation offer the potential to bridge the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the

  10. Tolerance of canine anastomoses to intraoperative radiation therapy

    International Nuclear Information System (INIS)

    Tepper, J.E.; Sindelar, W.; Travis, E.L.; Terrill, R.; Padikal, T.

    1983-01-01

    Radiation has been given intraoperatively to various abdominal structures in dogs, using a fixed horizontal 11 MeV electron beam at the Armed Forces Radiobiologic Research Institute. Animals were irradiated with single doses of 2000, 3000 and 4500 rad to a field which extended from the bifurcation of the aorta to the rib cage. All animals were irradiated during laparotomy under general anesthesia. Because the clinical use of intraoperative radiotherapy in cancer treatment will occasionally require irradiation of anastomosed large vessels and blind loops of bowel, the tolerance of aortic anastomoses and the suture lines of blind loops of jejunum to irradiation were studied. Responses in these experiments were scored at times up to one year after irradiation. In separate experiments both aortic and intestinal anastomoses were performed on each animal for evaluation of short term response. The dogs with aortic anastomoses showed adequate healing at all doses with no evidence of suture line weakening. On long-term follow-up one animal (2000 rad) had stenosis at the anastomosis and one animal (4500 rad) developed an arteriovenous fistula. Three of the animals that had an intestinal blind loop irradiated subsequently developed intussusception, with the irradiated loop acting as the lead point. One week after irradiation, bursting pressure of an intestinal blind loop was normal at 3000 rad, but markedly decreased at 4500 rad. No late complications were noted after the irradiation of the intestinal anastomosis. No late complicatons were observed after irradiation of intestinal anastomoses, but one needs to be cautious with regards to possible late stenosis at the site of an irradiated vascular anastomosis

  11. DNA Protection Protein, a Novel Mechanism of Radiation Tolerance: Lessons from Tardigrades.

    Science.gov (United States)

    Hashimoto, Takuma; Kunieda, Takekazu

    2017-06-15

    Genomic DNA stores all genetic information and is indispensable for maintenance of normal cellular activity and propagation. Radiation causes severe DNA lesions, including double-strand breaks, and leads to genome instability and even lethality. Regardless of the toxicity of radiation, some organisms exhibit extraordinary tolerance against radiation. These organisms are supposed to possess special mechanisms to mitigate radiation-induced DNA damages. Extensive study using radiotolerant bacteria suggested that effective protection of proteins and enhanced DNA repair system play important roles in tolerability against high-dose radiation. Recent studies using an extremotolerant animal, the tardigrade, provides new evidence that a tardigrade-unique DNA-associating protein, termed Dsup, suppresses the occurrence of DNA breaks by radiation in human-cultured cells. In this review, we provide a brief summary of the current knowledge on extremely radiotolerant animals, and present novel insights from the tardigrade research, which expand our understanding on molecular mechanism of exceptional radio-tolerability.

  12. Maximum tolerable radiation doses recommended by the Israel Advisory Committee on nuclear safety

    International Nuclear Information System (INIS)

    Tadmor, J.; Litai, D.; Lubin, E.

    1978-01-01

    Maximum tolerable doses have been recommended by the Israel Advisory Committee on Nuclear Safety. The recommendations which are based on a comparison with risks tolerated in other human activities, are for doses to radiation workers, for individual members of the population at the fence of a nuclear installation, and for the population at large, for both normal operating and accident conditions. Tolerable whole-body doses and doses to different critical organs are listed

  13. High Power Radiation Tolerant CubeSat Power System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — No vendor has yet to provide a radiation tolerant, high efficiency, small Power Management and Distribution module for the SmallSat and CubeSat market yet. Let alone...

  14. Attenuation of a radiation-induced conditioned taste aversion after the development of ethanol tolerance

    International Nuclear Information System (INIS)

    Hunt, W.A.; Rabin, B.M.

    1988-01-01

    An attempt to reduce a radiation-induced conditioned taste aversion (CTA) was undertaken by rendering animals tolerant to ethanol. Ethanol tolerance, developed over 5 days, was sufficient to block a radiation-induced taste aversion, as well as an ethanol-induced CTA. Several intermittent doses of ethanol, which did not induce tolerance but removed the novelty of the conditioning stimulus, blocked an ethanol-induced CTA but not the radiation-induced CTA. A CTA induced by doses of radiation up to 500 rads was attenuated. These data suggest that radioprotection developing in association with ethanol tolerance is a result of a physiological response to the chronic presence of ethanol not to the ethanol itself

  15. Mechanisms of cardiac transplantation tolerance in syngeneic rat radiation chimeras

    International Nuclear Information System (INIS)

    Moran, T.M.

    1981-01-01

    Seventy-five percent of adult LEW rats, lethally irradiated (860 R), transplanted with an RT-1 incompatible Wistar Furth (WF) heart or kidney and repopulated on day 2 with a 4:1 mixture of syngeneic thymus and bone marrow cells accept these grafts. In order to look at the ability of animals tolerating WF organ grafts to respond against WF spleen cells in vitro we developed a rat mixed lymphocyte culture. Tolerant animals were tested for the ability to respond to donor antigens and approximately half of the 50 animals tested, were responsive. We attempted to demonstrate suppressor cells which might be responsible for maintaining tolerance in the nonresponders. Neither mixtures at the sensitization or the effector level suggested that tolerance was being maintained by a suppressor cell. An in vivo assay which tested the ability of various cell populations to affect the survival of allogeneic hearts transplanted into sublethally irradiated recipients was then employed. Tolerance is induced using this protocol in a manner similar or identical to tolerance produced by neonatal injection of antigen. This tolerance might be maintained in part by suppressor cells which prevents the generation of clones of cells reactive against the heart donor. The mechanism of tolerance in rats with demonstrable clones of reactive cells remains to be determined

  16. Gamma irradiation facilities for radiation tolerance assessment of components and systems at SCK.CEN

    International Nuclear Information System (INIS)

    Coenen, S.; Decreton, M.

    1999-01-01

    This paper presents the different gamma irradiation facilities available at SCK-CEN (Mol, Belgium). With gamma dose rates ranging from 1 Gy/h up to 50 kGy/h, extensive environmental control and on-line instrumentation possibilities, they offer ideal test environments for the radiation tolerance assessment of components and systems for many applications where radiation tolerance is a concern. (authors)

  17. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    is linked to a different set of circumstances than the ones suggested by existing models in contemporary democratic theory. Reorienting the discussion of tolerance, the book raises the question of how to disclose new possibilities within our given context of affect and perception. Once we move away from......Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated...... by the desire to experiment and to become otherwise. The objective is to discuss what gets lost, conceptually as well as politically, when we neglect the subsistence of active tolerance within other practices of tolerance, and to develop a theory of active tolerance in which tolerance's mobilizing character...

  18. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated by the d...... these alternatives by returning to the notion of tolerance as the endurance of pain, linking this notion to exemplars and theories relevant to the politics of multiculturalism, religious freedom, and free speech....

  19. Technologies pioneered by LHC. Superconducting magnet and radiation-tolerant tracking detector

    International Nuclear Information System (INIS)

    Yamamoto, Akira; Unno, Yoshinobu

    2007-01-01

    In the LHC project of proton-proton collisions exploring the energy frontier, superconducting magnets and radiation-tolerant tracking detector play fundamental roles as key technologies. The superconducting magnets contribute to bending and focusing particle beam by using high magnetic field created with the NbTi superconductor cooled to the superfluid temperature of He (1.9 K). In order to overcome the unprecedented radiation damage and to capture the particles emerging with high energy and high density, the large area and highly radiation-tolerant silicon semiconductor tracking detector has been developed for the LHC experiment. (author)

  20. Tolerance of cut flowers to gamma-radiation

    International Nuclear Information System (INIS)

    Kikuchi, O.K.; Wiendl, F.M.; Arthur, V.

    1999-01-01

    Cut flowers were gamma-irradiated with doses of 0, 200, 400, 600, and 1000 Gy. Dianthuscaryophyllus (Caryophyllaceae), Gypsophila paniculata (Caryophyllaceae), Freesia sp (Iridaceae), Limonium sinuatum Mill. (Plumbaginaceae), L. latifolium Kuntze (Plumbaginaceae), Narcissus tazetta L. (Amaryllidaceae), Helichrysum bracteatum Andr. (Compositae) and Rhodanthe manglesii Lindl (Compositae) were tolerant up to 1000 Gy, without visible negative changes after irradiation and during the vase-life. Callistephus chinensis (Compositae) and Lilium longiflorum Thunb. (Liliaceae) were moderately tolerant, but were modified by high doses. Anthurium sp (Araceae), Strelitzia sp (Musaceae), Matthiola incana R. Br. (Cruciferae), Aechmea distichanta (Bromeliaceae), Consolida ajacis Niew (Ranunculaceae), Ranunculus sp (Ranunculaceae), Dendrobium phalenopsis (Orchidaceae) and Gerbera sp (Compositae) were not tolerant to a dose of 200 Gy. The most adequate flowers to be submitted to irradiation treatment for disinfestation purpose were those of the Caryophillaceae family and those which can be used as dried flowers, such as members of the Rhodanthe, Helichrysum and Limmonium genera. (author)

  1. The design and qualification of radiation tolerant equipment for the nuclear power industry

    International Nuclear Information System (INIS)

    Sharp, R.; Pater, L.

    1995-01-01

    The nuclear power industry has many demands for equipment tolerant to the damaging effects of radiation. The wide variety of applications, including components handling, tooling, monitoring and communications, means that a systematic evaluation of the effects of radiation on materials and components used for equipment in radioactive facilities is often required. This paper describes the various effects of radiation on equipment, and discusses how to manage them when using and designing equipment. (Author)

  2. Radiation Tolerant Temperature-Invariant Scintillation Modules, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation detectors are an invaluable tool for space applications spanning planetary science, astrophysics, heliophysics, space weather, and dosimetry for human...

  3. Radiation tolerance and mitigation strategies for FPGA:s in the ATLAS TileCal Demonstrator

    CERN Document Server

    Akerstedt, H; The ATLAS collaboration

    2013-01-01

    During 2014, demonstrator electronics will be installed in a Tile calorimeter "drawer" to get long term experience with the inherently redundant electronics proposed for a full upgrade scheduled for 2022. The new system, being FPGA-based, uses dense programmable logic which must be proven to be sufficently radiation tolerant. It must be protected against radiation induced single event upsets that corrupt memory and logic functions. Radiation induced errors need to be found and compensated for in time, to minimize data loss but also to avoid permanent damage. Strategies for detecting and correcting radiation induced errors in the Kintex-7 FPGA:s of the demonstrator are evaluated and discussed.

  4. Radiation tolerance and mitigation strategies for FPGA:s in the ATLAS TileCal Demonstrator

    CERN Document Server

    Akerstedt, H; The ATLAS collaboration; Drake, G; Muschter, S; Oreglia, M; Tang, F; Anderson, K; Paramonov, A

    2013-01-01

    During 2014, upgrade-demonstrator electronics will be installed in a Tile calorimeter drawer to obtain long term experience with the inherently redundant electronics proposed for a full upgrade scheduled for 2022. The new, FPGA-based system uses dense programmable logic, which must be proven to be sufficiently radiation tolerant. It must also be protected against radiation induced single event upsets that can corrupt memory and logic Radiation induced errors need to be found and compensated for in time to minimize data loss, and also to avoid permanent damage. Strategies for detecting and correcting radiation induced errors in the Kintex-7 FPGAs on the demonstrator electronics are evaluated and discussed.

  5. Radiation tolerance assurance of technical equipment in the LHC radiation monitoring for technical equipment at the LHC

    CERN Document Server

    Wijnands, Thijs; CERN. Geneva. TS Department

    2005-01-01

    In contrast with other accelerators at CERN, a large amount of technical equipment will be located in the LHC tunnel, the underground areas and in the experimental caverns where they will be exposed to radiation. Nearly all this equipment makes, to a certain extent, use of commercial microelectronics which is extremely sensitive to radiation damage, both instantaneous damage and cumulative damage. Examples in the TS Department are the electronics for the position sensors of the low beta quadrupoles, the access system, the cooling and ventilation units, the electronics for the electrical distribution, the oxygen deficiency monitors and fire detection systems. The basic effects of radiation on electronic systems and components are well understood because similar problems with radiation are encountered in the aerospace and aviation industry. Since 1998, an efficient and original Radiation Tolerance Assurance approach for the LHC machine has been established. Its aim is to minimise the effects of radiation damage...

  6. Pitch dependence of the tolerance of CMOS monolithic active pixel sensors to non-ionizing radiation

    International Nuclear Information System (INIS)

    Doering, D.; Deveaux, M.; Domachowski, M.; Fröhlich, I.; Koziel, M.; Müntz, C.; Scharrer, P.; Stroth, J.

    2013-01-01

    CMOS monolithic active pixel sensors (MAPS) have demonstrated excellent performance as tracking detectors for charged particles. They provide an outstanding spatial resolution (a few μm), a detection efficiency of ≳99.9%, very low material budget (0.05%X 0 ) and good radiation tolerance (≳1Mrad, ≳10 13 n eq /cm 2 ) (Deveaux et al. [1]). This makes them an interesting technology for various applications in heavy ion and particle physics. Their tolerance to bulk damage was recently improved by using high-resistivity (∼1kΩcm) epitaxial layers as sensitive volume (Deveaux et al. [1], Dorokhov et al. [2]). The radiation tolerance of conventional MAPS is known to depend on the pixel pitch. This is as a higher pitch extends the distance, which signal electrons have to travel by thermal diffusion before being collected. Increased diffusion paths turn into a higher probability of loosing signal charge due to recombination. Provided that a similar effect exists in MAPS with high-resistivity epitaxial layer, it could be used to extend their radiation tolerance further. We addressed this question with MIMOSA-18AHR prototypes, which were provided by the IPHC Strasbourg and irradiated with reactor neutrons. We report about the results of this study and provide evidences that MAPS with 10μm pixel pitch tolerate doses of ≳3×10 14 n eq /cm 2

  7. Determination of tolerances of mirror displacement and radiator gas impurity for the CBM RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Adamczewski-Musch, J. [GSI Darmstadt (Germany); Becker, K.-H. [University Wuppertal (Germany); Belogurov, S. [ITEP Moscow (Russian Federation); Boldyreva, N. [PNPI Gatchina (Russian Federation); Chernogorov, A. [ITEP Moscow (Russian Federation); Deveaux, C. [University Gießen (Germany); Dobyrn, V. [PNPI Gatchina (Russian Federation); Dürr, M. [University Gießen (Germany); Eom, J. [Pusan National University (Korea, Republic of); Eschke, J. [GSI Darmstadt (Germany); Höhne, C. [University Gießen (Germany); Kampert, K.-H. [University Wuppertal (Germany); Kleipa, V. [GSI Darmstadt (Germany); Kochenda, L. [PNPI Gatchina (Russian Federation); Kolb, B. [GSI Darmstadt (Germany); Kopfer, J. [University Wuppertal (Germany); Kravtsov, P. [PNPI Gatchina (Russian Federation); Lebedev, S.; Lebedeva, E. [University Gießen (Germany); Leonova, E. [PNPI Gatchina (Russian Federation); and others

    2014-12-01

    The CBM experiment at the future FAIR facility will explore nuclear matter at high net-baryon densities. One of the key observables is di-leptons as they penetrate the created matter without further strong interactions. A gaseous RICH detector in a standard projective geometry using spherical mirrors is one of two detector elements for the required electron identification. The mirror system consists of about 72 trapezoidal mirror tiles. Any misalignment between the tiles relative to the nominal common spherical surface leads to reduction of the reconstruction efficiency of Cherenkov rings and deterioration of their resolution. To determine tolerances in mirror misalignment extensive simulation and measurement studies were carried out. Pure CO{sub 2} will be used as radiator gas. Gas contamination, mainly moisture and Oxygen, reduces the number of detected photons per ring and worsens the quality of reconstructed Cherenkov rings. Therefore a study was carried out to determine tolerances in radiator gas contamination. - Highlights: • Mirror misalignment leads to ring deformation in a RICH detector. • Radiator contamination leads to resolution deterioration of fitted rings. • To determine tolerances measurements and simulations were carried out. • Mirror displacements of up to 0.32 mm at any mirror side can be tolerated. • Oxygen (moisture) contamination of up to 1% (0.0011%) can be safely tolerated.

  8. Normal tissue tolerance to external beam radiation therapy: Skin

    International Nuclear Information System (INIS)

    Ginot, A.; Doyen, J.; Hannoun-Levi, J.M.; Courdi, A.

    2010-01-01

    Acute skin toxicity is frequent during radiation therapy and can lead to temporary arrest of the treatment. Chronic toxicity can occur and conduct to cosmetic problems. Alopecia is the most frequent toxicity concerning hair and is most of the time reversible. Several factors linked to patients influence skin toxicity, such as under-nutrition, old age, obesity, smoking, skin diseases, autoimmune diseases, failure of DNA reparation. Skin, hair and nail toxicities depend also on radiation schedule. Acute toxicity is greater when dose per fraction increases. Chronic and acute toxicities are more often when total dose increases. Under 45 Gy, the risk of severe skin toxicity is low, and begins above 50 Gy. Skin toxicity depends also on the duration of radiotherapy and split course schedules are associated with less toxicities. Irradiation surface seems to influence skin toxicity but interaction is more complex. Reirradiation is often feasible in case of cancer recurrence but with a risk of grade 3-4 toxicity above all in head and neck cancer. The benefit/risk ratio has to be always precisely evaluated. Permanent alopecia is correlated with the follicle dose. Modern techniques of radiation therapy allow to spare skin. (authors)

  9. Application of organ tolerance dose-constraints in clinical studies in radiation oncology

    International Nuclear Information System (INIS)

    Doerr, Wolfgang; Herrmann, Thomas; Baumann, Michael

    2014-01-01

    In modern radiation oncology, tolerance dose-constraints for organs at risk (OAR) must be considered for treatment planning, but particularly in order to design clinical studies. Tolerance dose tables, however, only address one aspect of the therapeutic ratio of any clinical study, i.e., the limitation of adverse events, but not the desired potential improvement in the tumor effect of a novel treatment strategy. A sensible application of ''tolerance doses'' in a clinical situation requires consideration of various critical aspects addressed here: definition of tolerance dose, specification of an endpoint/symptom, consideration of radiation quality and irradiation protocol, exposed volume and dose distribution, and patient-related factors of radiosensitivity. The currently most comprehensive estimates of OAR radiation tolerance are in the QUANTEC compilations (2010). However, these tolerance dose values must only be regarded as a rough orientation and cannot answer the relevant question for the patients, i.e., if the study can achieve a therapeutic advantage; this can obviously be answered only by the final scientific analysis of the study results. Despite all limitations, the design of clinical studies should currently refer to the QUANTEC values for appreciation of the risk of complications, if needed supplemented by one's own data or further information from the literature. The implementation of a consensus on the safety interests of the patients and on an application and approval process committed to progress in medicine, with transparent quality-assuring requirements with regard to the structural safeguarding of the study activities, plays a central role in clinical research in radiation oncology. (orig.) [de

  10. Radiation-tolerant delta-sigma time-to-digital converters

    CERN Document Server

    Cao, Ying; Steyaert, Michiel

    2015-01-01

    This book focuses on the design of a Mega-Gray (a standard unit of total ionizing radiation) radiation-tolerant ps-resolution time-to-digital converter (TDC) for a light detection and ranging (LIDAR) system used in a gamma-radiation environment. Several radiation-hardened-by-design (RHBD) techniques are demonstrated throughout the design of the TDC and other circuit techniques to improve the TDC's resolution in a harsh environment are also investigated. Readers can learn from scratch how to design a radiation-tolerant IC. Information regarding radiation effects, radiation-hardened design techniques and  measurements are organized in such a way that readers can easily gain a thorough understanding of the topic. Readers will also learn the design theory behind the newly proposed delta-sigma TDC. Readers can quickly acquire knowledge about the design of radiation-hardened bandgap voltage references and low-jitter relaxation oscillators, which are introduced in the content from a designer's perspective.   · �...

  11. Disinfestation of agricultural products with electron beams and their radiation tolerance

    International Nuclear Information System (INIS)

    Hayashi, Toru

    1996-01-01

    Some agricultural products contaminated with insect pests are fumigated with methyl bromide for quarantine purposes. However, the use of methyl bromide is preferably restricted because of its ozone depleting effect. Therefore, establishing alternative quarantine techniques is highly desirable; one such technique is exposure to ionizing radiation. Few data are available on the effects of radiation on insect pests other than fruit flies and stored-product insects and on the radiation tolerance of host commodities. Radiation technology as an alternative to methyl bromide fumigation will be used to inactivate not only insects but also mites, spider mites, thrips, nematodes, scales, mealybugs and thrips contaminating fruits, grains, cut flowers, vegetables, timbers, seedlings and seeds. In order to collect data on the effects of irradiation on pests and host commodities, IAEA and FAO have conducted an international project, 'FAO/IAEA Coordinated Research Programme on Irradiation as a Quarantine Treatment of Mites, Nematodes and Insects other than Fruit Fly' since 1992. The project determines the minimum doses necessary to inactivate pests and the maximum doses host commodities tolerate. All pests except nematodes can be inactivated at doses 400Gy or lower. Various varieties of cut flowers and herbs are tolerant to 400Gy of radiation, although some flowers and herbs such as chrysanthemum, rose, lily, calla, anthurium, sweet pea, iris, dill, basil and arugula are intolerant to 200Gy of radiation. Japanese research project on treatment of cut flowers with electron beams carried out mainly by Yokohama Plant Protection Station greatly contributes to these conclusions. Aqueous solution (2%) of sucrose, glucose, fructose or maltose prevents radiation-induced detrimental effects of radiation on chrysanthemums. Sugars reduce radiation-induced physiological deterioration of chrysanthemums. (author)

  12. Normal tissue tolerance to external beam radiation therapy: Brain and hypophysis

    International Nuclear Information System (INIS)

    Haberer, S.; Assouline, A.; Mazeron, J.J.

    2010-01-01

    Anticancer treatments-induced central nervous system neurotoxicity has become a major problem in recent years. Real advances in therapeutic results for cancer treatments have improved patients survival. Nowadays, central nervous system radiation therapy is widely prescribed, both for palliative and curative treatments in the management of malignant or benign tumors. Recent data on tolerance of normal central nervous system to radiation therapy are reviewed here, early and delayed radiation-induced effects are described and dose recommendations are suggested for clinical practice. (authors)

  13. Disruption of Circadian rhythms enhances radiation tolerance in mice

    International Nuclear Information System (INIS)

    Patil, Shrikant L.; Krishna, A.P.; Somashekarappa, H.M.; Patil, Rajashekar K.

    2014-01-01

    Whether an alteration in responses to the radiations depends on the phase of Circadian rhythm, this has been explored previously. The results however have been inconclusive and only survival rate of animals has been considered to represent the effect. Circadian phase has been shown to be critical in many therapeutic procedures. The present study was conducted on control group of mice (12L: 12D), extended day length and night length by imposing 24 hrs of light followed by 24 hrs of darkness, a third group received (8L: 8D) light: day cycles. These regimes were operational for seven days, at the end of seventh day mice from three different groups were exposed to 3 Gy of total body gamma radiation. Survival study, extent of lipid peroxidation and antioxidant status was estimated. Radioresistance was found to be enhanced in mice maintained at 8L: 8D cycle. There was no significant changes observed in mice of time shift group (24L: 24D). The corresponding shift in the acrophase of radioresistance following a sudden time shift supports the effect of disrupted circadian rhythms. (author)

  14. On the development of radiation tolerant surveillance camera from consumer-grade components

    Directory of Open Access Journals (Sweden)

    Klemen Ambrožič

    2017-01-01

    Full Text Available In this paper an overview on the process of designing a radiation tolerant surveillance camera from consumer grade components and commercially available particle shielding materials is given. This involves utilization of Monte-Carlo particle transport code MCNP6 and ENDF/B-VII.0 nuclear data libraries, as well as testing the physical electrical systems against γ radiation, utilizing JSI TRIGA mk. II fuel elements as a γ-ray sources. A new, aluminum, 20 cm × 20 cm × 30 cm irradiation facility with electrical power and signal wire guide-tube to the reactor platform, was designed and constructed and used for irradiation of large electronic and optical components assemblies with activated fuel elements. Electronic components to be used in the camera were tested against γ-radiation in an independent manner, to determine their radiation tolerance. Several camera designs were proposed and simulated using MCNP, to determine incident particle and dose attenuation factors. Data obtained from the measurements and MCNP simulations will be used to finalize the design of 3 surveillance camera models, with different radiation tolerances.

  15. On the development of radiation tolerant surveillance camera from consumer-grade components

    Science.gov (United States)

    Klemen, Ambrožič; Luka, Snoj; Lars, Öhlin; Jan, Gunnarsson; Niklas, Barringer

    2017-09-01

    In this paper an overview on the process of designing a radiation tolerant surveillance camera from consumer grade components and commercially available particle shielding materials is given. This involves utilization of Monte-Carlo particle transport code MCNP6 and ENDF/B-VII.0 nuclear data libraries, as well as testing the physical electrical systems against γ radiation, utilizing JSI TRIGA mk. II fuel elements as a γ-ray sources. A new, aluminum, 20 cm × 20 cm × 30 cm irradiation facility with electrical power and signal wire guide-tube to the reactor platform, was designed and constructed and used for irradiation of large electronic and optical components assemblies with activated fuel elements. Electronic components to be used in the camera were tested against γ-radiation in an independent manner, to determine their radiation tolerance. Several camera designs were proposed and simulated using MCNP, to determine incident particle and dose attenuation factors. Data obtained from the measurements and MCNP simulations will be used to finalize the design of 3 surveillance camera models, with different radiation tolerances.

  16. Radiation Tolerance Qualification Tests of the Final Source Interface Unit for the ALICE Experiment

    CERN Document Server

    Dénes, E; Futó, E; Kerék, A; Kiss, T; Molnár, J; Novák, D; Soós, C; Tölyhi, T; Van de Vyvre, P

    2007-01-01

    The ALICE Detector Data Link (DDL) is a high-speed optical link designed to interface the readout electronics of ALICE sub-detectors to the DAQ computers. The Source Interface Unit (SIU) of the DDL will operate in radiation environment. Previous tests showed that a configuration loss of SRAM-based FPGA devices may happen and the frequency of undetected data errors in the FPGA user memory area is also not acceptable. Therefore, we redesigned the SIU card using another FPGA based on flash technology. In order to detect bit errors in the user memory we added parity check logic to the design. The new SIU has been extensively tested using neutron and proton irradiation to verify its radiation tolerance. In this paper we summarize the design changes, introduce the final design, and the results of the radiation tolerance measurements on the final card.

  17. The influence of fractionation and repair kinetics on radiation tolerance

    International Nuclear Information System (INIS)

    Rongen, E. van.

    1989-01-01

    The effect of irradiation of biological tissues is described as the sum of a linear and a quadratic function of the radiation dose, in which α and β and β are denoted as the coefficients of the linear and quadratic terms respectively. The rate of repair of radiation damage is expressed by the half-life time T 1 / 2. The purpose of the study described in this thesis was to determine the α/β and T 1 / 2 values for early and late effects in lungs and kidneys of the rat. Rats have been irradiated upon one of both organs in various numbers of fractions, which have been administered with long or short time intervals in order to obtain respectively complete and incomplete repair. From the results values for α/β and T 1 / 2 could be obtained by means of computer codes. The results of this investigation indicate that for the lung differences exist in α/β for early and late effects. The α/β value for early effects being larger: 3.5 Gy, than the one for late effecfts: 2.3 Gy. The values for T 1 / 2 were respectively 1.0 hour for early and 1.1 hour for late effects. The kidney experiments resulted in equal α/β values for early and late effects: resp. 1.7 and 1.8 Gy. The T 1 / 2 values, however, differed being resp. 1.6 hour and 2.1 hour. Also the influence of the fraction dose upon the α/β and T 1 / 2 values was investigated. For the lung such effects have not been found. In the kidney only between 20 and 40 weeks after the irradiation differences were observed, which disappeared after this period. The results of this investigation indicate that, in radiotherapy of tumors where lungs and kidneys are contained in the radiation field, a scheme following which a large number of small fractions are administered, would give therapeutical advantage with respect to standard therapy. (H.W.). 240 refs.; 38 figs.; 37 tabs

  18. Superior radiation tolerance of thin epitaxial silicon detectors

    CERN Document Server

    Kramberger, G; Fretwurst, E; Honniger, F; Lindström, G; Pintilie, I; Röder, R; Schramm, A; Stahl, J

    2003-01-01

    For the LHC upgrade (fluences up to 10**1**6 p/cm**2) epi-Si devices are shown to be a viable solution. No type inversion was measured up to 1.3 multiplied by 10**1**524 GeV/c protons/cm**2 and the charge collection efficiency (CCE) remained close to 100%. For reactor neutrons CCE was measured to be 60% at 8 multiplied by 10**1**5 n/cm **2. Annealing measurements have shown that only moderate cooling during beam off periods would be necessary. As a tentative explanation for the superior quality of these devices, we assume that radiation-induced donor generation leads to compensation effects of deep acceptors. In the future, we will extend the experiments to fluences up to 10**1**6 p/cm**2 and use also different variants of the epi-Si material and device geometry.

  19. Investigation on a radiation tolerant betavoltaic battery based on Schottky barrier diode

    International Nuclear Information System (INIS)

    Liu Yebing; Hu Rui; Yang Yuqing; Wang Guanquan; Luo Shunzhong; Liu Ning

    2012-01-01

    An Au–Si Schottky barrier diode was studied as the energy conversion device of betavoltaic batteries. Its electrical performance under radiation of Ni-63 and H-3 sources and radiation degradation under Am-241 were investigated and compared with those of the p–n junction. The results show that the Schottky diode had a higher I sc and harder radiation tolerance but lower V oc than the p–n junction. The results indicated that the Schottky diode can be a promising candidate for energy conversion of betavoltaic batteries. - Highlights: ► The Schottky diode was used as the converter of the betavoltaic battery. ► The radiation damage of converter was accelerated by using alpha particles. ► The Schottky diode has higher radiation resistance than that of the p–n junction. ► The Schottky diode could still be a promising converter of the betavoltaic battery.

  20. Tolerance of normal tissues to radiation therapy: Ear

    International Nuclear Information System (INIS)

    Fleury, B.; Lapeyre, M.

    2010-01-01

    The main objective of this work was to describe, based on a literature survey, the radiation-induced toxicity of the ear and to try to establish the limiting dose. The limiting toxicity was the sensorineural hearing loss. A dose-effect relationship has been described by several authors. Thirty to 40% of patients who are irradiated for head and neck cancer are concerned, but the intensity of the hearing loss tends to depend on the exact localisation of the primary tumour: nasopharyngeal irradiations, paranasal sinusal and parotid irradiation are at greater risk of complication. High frequencies are more vulnerable than the lower ones. Age of patients, as well as baseline hearing abilities, deeply influence the issue. As far as possible, the dose to the inner ear (the cochlea more precisely) should be kept under 40 Gy. In case of association with other causes of toxicity (such as age, low baseline value, association to cisplatin), this dose should be as low as possible. Should carcinologic constraints lead to toxic doses, then patients should be properly informed. (authors)

  1. Study of defects in radiation tolerant semiconductor SiC

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Hisayoshi; Kawasuso, Atsuo; Ohshima, Takeshi; Yoshikawa, Masahito; Nashiyama, Isamu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Okumura, Hajime; Yoshida, Sadafumi

    1997-03-01

    Electron spin resonance (ESR) was used to study defects introduced in n-type 6H-SiC by 3 MeV electron irradiation. Two ESR signals labeled A and B related to radiation induced defects were observed. An ESR signal B can be explained by a fine interaction with an effective spin S=1. The g and D tensors of the signal B were found to be axially symmetric along the c-axis. The principal values of the g were obtained to be g parallel = 2.003 and g perpendicular = 2.008, and the absolute value of the D was 3.96x10{sup -2} cm{sup -1} at 100 K for this signal. It was also found that the value |D| decreased with increasing temperature. Isochronal annealing showed that the A and B centers have annealing stages of {approx_equal}200degC and {approx_equal}800degC, respectively. Tentative structural models are discussed for these ESR centers. (author)

  2. [Tolerance of the association sucralfate / Cu-Zn salts in radiation dermatitis].

    Science.gov (United States)

    De Rauglaudre, G; Courdi, A; Delaby-Chagrin, F; d'Hombres, A; Hannoun-Levi, J-M; Moureau-Zabotto, L; Richard-Tallet, A; Rouah, Y; Salem, N; Thomas, O; Nocera, T; Mery, S; Merial-Kieny, C

    2008-01-01

    The aim of this study was to evaluate the tolerance of topical application of the combination sucralfate / copper zinc salts in radiation dermatitis in women suffering from breast cancer and treated by radiotherapy. 47 patients (average age : 57,5 years) that have to be treated by radiation therapy on non lesional areas, were included into this open multicentric study. They had to apply Cicalfate cream twice a day, from the fi rst radiation therapy session and during 10 weeks. Patients were treated by photon- or electrontherapy (72 % et 28 %, respectively; cumulated total dose : 58,6Gy). Tolerance was considered to be excellent. The radiation dermatitis (score NCIC > or = 2) was noted at the 3rd week of radiotherapy only in 5 % of the subjects and in 53 % of the subjects, the last week of treatment. Pruritus was significantly increased at D21. Pain and discomfort were increased at D28, but remained low intensity. The soothing effect of the combination of sucralfate/ copper zinc salts were considered satisfying or very satisfying by investigators and patients during the study, varying from 94 to 100 % of satisfaction. The impact of radiation therapy on the patients'quality of life, assessed by DLQI, evaluated at the end of the study was not statistically different from the score calculated at D7 (DLQI=0,8 et D7 versus DLQI=1 at D70). Thus, topical application of the combination sucralfate / copper zinc salts can be used in the indication radiation dermatitis.

  3. A radiation tolerant fiber-optic readout system for the LHCb Silicon Tracker

    CERN Document Server

    Agari, M; Blouw, J; Hofmann, W; Knöpfle, K T; Löchner, S; Schmelling, M; Schwingenheuer, B; Pugatch, V; Pylypchenko, Y; Bay, A; Carron, B; Fauland, P; Frei, R; Jiménez-Otero, S; Perrin, A; Tran, M T; Van Hunen, J J; Vervink, K; Vollhardt, A; Voss, H; Adeva, B; Esperante-Pereira, D; Lois, C; Vázquez, P; Bernhard, R P; Bernet, R; Gassner, J; Köstner, S; Lehner, F; Needham, M; Steinkamp, O; Straumann, U; Volyanskyy, D; Wenger, A

    2005-01-01

    A fiber-optic readout system has been designed for the LHCb Silicon Tracker to transmit the detector data to the counting room at a distance of 120 m from the detectors. In total, data from over 272000 detector channels have to be transmitted at an average trigger frequency of 1.1 MHz. In the design of the system, special attention was given to its radiation tolerance, as the transmitting section is located close to the beamline and therefore is exposed to moderate particle fluences and ionizing dose during the expected operational life of 10 years. We give a general overview of the readout link scheme and present performance data on its reliability and radiation tolerance obtained from first preseries elements of the system. Poster presented on the 10th European Symposium on Semiconductor Detectors, June 12th â€" June 16th 2005, Wildbad Kreuth, Germany.

  4. Intrinsic radiation tolerance of ultra-thin GaAs solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hirst, L. C.; Yakes, M. K.; Warner, J. H.; Schmieder, K. J.; Walters, R. J.; Jenkins, P. P. [U.S. Naval Research Laboratory, 4555 Overlook Ave. SW., Washington, D.C. 20375 (United States); Bennett, M. F. [Sotera Defense Solutions, Inc., Annapolis Junction, Maryland 20701-1067 (United States)

    2016-07-18

    Radiation tolerance is a critical performance criterion of photovoltaic devices for space power applications. In this paper we demonstrate the intrinsic radiation tolerance of an ultra-thin solar cell geometry. Device characteristics of GaAs solar cells with absorber layer thicknesses 80 nm and 800 nm were compared before and after 3 MeV proton irradiation. Both cells showed a similar degradation in V{sub oc} with increasing fluence; however, the 80 nm cell showed no degradation in I{sub sc} for fluences up to 10{sup 14 }p{sup +} cm{sup −2}. For the same exposure, the I{sub sc} of the 800 nm cell had severely degraded leaving a remaining factor of 0.26.

  5. Robust, Radiation Tolerant Command and Data Handling and Power System Electronics for SmallSats

    Science.gov (United States)

    Nguyen, Hanson Cao; Fraction, James

    2018-01-01

    In today's budgetary environment, there is significant interest within the National Aeronautics and Space Administration (NASA) to enable small robotic science missions that can be executed faster and cheaper than previous larger missions. To help achieve this, focus has shifted from using exclusively radiation-tolerant or radiation-hardened parts to using more commercial-off-the-shelf (COTS) components for NASA small satellite missions that can last at least one year in orbit. However, there are some portions of a spacecraft's avionics, such as the Command and Data Handling (C&DH) subsystem and the Power System Electronics (PSE) that need to have a higher level of reliability that goes beyond what is attainable with currently available COTS parts. While there are a number of COTS components that can withstand a total ionizing dose (TID) of tens or hundreds of kilorads, there is still a great deal of concern about tolerance to and mitigation of single-event effects (SEE).

  6. Conceptual design of a versatile radiation tolerant integrated signal conditioning circuit for resistive sensors

    Energy Technology Data Exchange (ETDEWEB)

    Leroux, P. [Katholieke Hogeschool Kempen, Kleinhoefstraat 4, B-2440 Geel (Belgium); Katholieke Universiteit Leuven, Dept. ESAT-MICAS, Kasteelpark Arenberg 10, B-3001 Heverlee (Belgium); SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium); Sterckx, J. [Katholieke Hogeschool Kempen, Kleinhoefstraat 4, B-2440 Geel (Belgium); Van Uffelen, M.; Damiani, C. [Fusion 4 Energy, Ed. B3, c/Josep, no 2, Torres Diagonal Litoral, 08019 Barcelona (Spain)

    2011-07-01

    This paper presents the design of a radiation tolerant configurable discrete time CMOS signal conditioning circuit for use with resistive sensors like strain gauge pressure sensors. The circuit is intended to be used for remote handling in harsh environments in the International Thermonuclear Experimental fusion Reactor (ITER). The design features a 5 V differential preamplifier using a Correlated Double Sampling (CDS) architecture at a sample rate of 20 kHz and a 24 V discrete time post amplifier. The gain is digitally controllable between 27 and 400 in the preamplifier and between 1 and 8 in the post amplifier. The nominal input referred noise voltage is only 8.5 {mu}V while consuming only 1 mW. The circuit has a simulated radiation tolerance of more than 1 MGy. (authors)

  7. Recent progress of the RD50 Collaboration – Development of radiation tolerant tracking detectors

    CERN Document Server

    Moll, M

    2014-01-01

    The CERN RD50 Collaboration "Radiation hard semiconductor devices for high luminosity col- liders" is undertaking a massive R&D; programme across High Energy Physics (HEP) Experi- ments boundaries to develop silicon sensors with increased radiation tolerance. Highest priority is to provide concepts and prototypes of high performance silicon sensors for the High-Luminosity Large Hadron Collider (HL-LHC) Experiments at CERN and other future HEP Experiments op- erating in severe radiation environments. This paper gives an overview of the RD50 collaboration activities and describes some examples of recent developments. Emphasis is put on the charac- terization of microscopic radiation induced defects and their impact on the sensor performance, the evaluation and parametrization of electric fields inside irradiated sensors, progress in device modeling using TCAD tools, the use of p-type silicon as strip and pixel sensor material and finally the first steps towards the exploitation of impact ionization ( charge...

  8. Modelling and design of high efficiency radiation tolerant indium phosphide space solar cells

    International Nuclear Information System (INIS)

    Goradia, C.; Geier, J.V.; Weinberg, I.

    1987-01-01

    Using a fairly comprehensive model, the authors did a parametric variation study of the InP shallow homojunction solar cell with a view to determining the maximum realistically achievable efficiency and an optimum design that would yield this efficiency. Their calculations show that with good quality epitaxial material, a BOL efficiency of about 20.3% at 1AMO, 25 0 C may be possible. The design parameters of the near-optimum cell are given. Also presented are the expected radiation damage of the performance parameters by 1MeV electrons and a possible explanation of the high radiation tolerance of InP solar cells

  9. Radiation tolerant optical links for the readout of the ATLAS experiment

    CERN Document Server

    Pearce, M

    2000-01-01

    The ATLAS experiment will use radiation tolerant optical links to transfer data to and from sub-detector systems. The link specifications can be broadly divided into two classes, represented by the inner tracking detectors and the electromagnetic calorimeter. A feature common to all the readout links is the use of vertical cavity surface emitting laser diodes coupled to multimode optical fibres. Results from the development for both of these environments are reviewed with particular attention bring paid to irradiation studies. (8 refs).

  10. Development of a construction and manufacturing techniques of complementary transistors for the radiation tolerant integrated circuits

    Directory of Open Access Journals (Sweden)

    Gorban A. N.

    2011-06-01

    Full Text Available The construction of vertical complementary transistors with the full dielectric isolation is developed, new technolo-gical processes of creation on their basis the radiation tolerant integrated circuits with parameters which provide low values of a leakage current along with the considerable values of a forward current and breakdown voltage at the information signals exchange frequency of about 500 kHz are developed.

  11. Tolerance to Ultraviolet Radiation of Psychrotolerant Yeasts and Analysis of Their Carotenoid, Mycosporine, and Ergosterol Content.

    Science.gov (United States)

    Villarreal, Pablo; Carrasco, Mario; Barahona, Salvador; Alcaíno, Jennifer; Cifuentes, Víctor; Baeza, Marcelo

    2016-01-01

    Yeasts colonizing the Antarctic region are exposed to a high ultraviolet radiation evolving mechanisms to minimize the UV radiation damages, such as the production of UV-absorbing or antioxidant compounds like carotenoid pigments and mycosporines. Ergosterol has also been suggested to play a role in this response. These compounds are also economically attractive for several industries such as pharmaceutical and food, leading to a continuous search for biological sources of them. In this work, the UV-C radiation tolerance of yeast species isolated from the sub-Antarctic region and their production of carotenoids, mycosporines, and ergosterol were evaluated. Dioszegia sp., Leuconeurospora sp. (T27Cd2), Rhodotorula laryngis, Rhodotorula mucilaginosa, and Cryptococcus gastricus showed the highest UV-C radiation tolerance. The yeasts with the highest content of carotenoids were Dioszegia sp. (OHK torulene), Rh. laryngis (torulene and lycopene), Rh. mucilaginosa, (torulene, gamma carotene, and lycopene), and Cr. gastricus (2-gamma carotene). Probable mycosporine molecules and biosynthesis intermediates were found in Rh. laryngis, Dioszegia sp., Mrakia sp., Le. creatinivora, and Leuconeurospora sp. (T27Cd2). Ergosterol was the only sterol detected in all yeasts, and M. robertii and Le. creatinivora showed amounts higher than 4 mg g−1. Although there was not a well-defined relation between UV-C tolerance and the production of these three kinds of compounds, the majority of the yeasts with lower amounts of carotenoids showed lower UV-C tolerance. Dioszegia sp., M. robertii, and Le. creatinivora were the greatest producers of carotenoids, ergosterol, and mycosporines, respectively, representing good candidates for future studies intended to increase their production for large-scale applications.

  12. Radiation tolerance of normal temporal bone structures: implications for gamma knife stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Linskey, Mark E.; Johnstone, Peter A.

    2003-01-01

    Popular current thought states that hearing loss and facial weakness after radiosurgery of vestibular schwannomas is a function of cranial nerve damage. Although this may be true in some cases, the middle and inner ear contain rich networks of other sensitive structures that are at risk after radiotherapy and that may contribute to toxicity afterward. We reviewed the limited reported data regarding radiation tolerance of external, middle, and inner ear structures, and perspectives for therapy with gamma knife stereotactic radiosurgery are addressed

  13. Design of two digital radiation tolerant integrated circuits for high energy physics experiments data readout

    CERN Document Server

    Bonacini, Sandro

    2003-01-01

    High Energy Physics research (HEP) involves the design of readout electron- ics for its experiments, which generate a high radiation ¯eld in the detectors. The several integrated circuits placed in the future Large Hadron Collider (LHC) experiments' environment have to resist the radiation and carry out their normal operation. In this thesis I will describe in detail what, during my 10-months partic- ipation in the digital section of the Microelectronics group at CERN, I had the possibility to work on: - The design of a radiation-tolerant data readout digital integrated cir- cuit in a 0.25 ¹m CMOS technology, called \\the Kchip", for the CMS preshower front-end system. This will be described in Chapter 3. - The design of a radiation-tolerant SRAM integrated circuit in a 0.13 ¹m CMOS technology, for technology radiation testing purposes and fu- ture applications in the HEP ¯eld. The SRAM will be described in Chapter 4. All the work has carried out under the supervision and with the help of Dr. Kostas Klouki...

  14. In vitro induction of variability through radiation for late blight resistance and heat tolerance in potato

    International Nuclear Information System (INIS)

    Gosal, S.S.; Das, A.; Gopal, J.; Minocha, J.L.; Chopra, H.R.; Dhaliwal, H.S.

    2001-01-01

    In vitro cultured shoots of potato, cvs. 'Kufri Jyoti' and 'Kufri Chandramukhi', were irradiated with 20 and 40 Gy gamma rays. Microtubers, obtained from MIV3 shoots multiplied in vitro, were planted in pots. The resulting plants were screened for resistance to late blight, using detached leaf method. In 'Kufri Chandramukhi', 42% plants and in 'Kufri Jyoti' 36% plants, obtained from 40 Gy treatment, showed resistance to late blight. The frequency of resistant plants was lower from 20 Gy treatment. The progenies of putatively resistant plants were grown in field, and inoculated with sporangial inoculum of late blight fungus. The field grown progeny segregated for disease resistance, and approximately 56% plants showed resistance. During the next propagation, the frequency of resistant plants increased to 72%. For developing heat tolerance, microtubers obtained from 20 and 40 Gy treatments and in vitro multiplied M 1 V 3 shoots were cultured at high temperature of 28C. In both varieties, the number of the microtubers per plant was highly reduced and the resulting microtubers had distorted shape but showed better germination (62%), even in early sowing at relatively higher temperature. Of the two radiation doses, the higher dose of 40 Gy gave better results in both the varieties. Heat tolerance was also assessed from chlorophyll persistence. The progenies from putative heat-tolerant plants were tested in field by planting at higher temperature in two subsequent generations. The heat tolerant plants segregated in each generation, but the frequency of heat-tolerant plants increased. (author)

  15. The essential role of the Deinococcus radiodurans ssb gene in cell survival and radiation tolerance.

    Directory of Open Access Journals (Sweden)

    J Scott Lockhart

    Full Text Available Recent evidence has implicated single-stranded DNA-binding protein (SSB expression level as an important factor in microbial radiation resistance. The genome of the extremely radiation resistant bacterium Deinococcus radiodurans contains genes for two SSB homologs: the homodimeric, canonical Ssb, encoded by the gene ssb, and a novel pentameric protein encoded by the gene ddrB. ddrB is highly induced upon exposure to radiation, and deletions result in decreased radiation-resistance, suggesting an integral role of the protein in the extreme resistance exhibited by this organism. Although expression of ssb is also induced after irradiation, Ssb is thought to be involved primarily in replication. In this study, we demonstrate that Ssb in D. radiodurans is essential for cell survival. The lethality of an ssb deletion cannot be complemented by providing ddrB in trans. In addition, the radiation-sensitive phenotype conferred by a ddrB deletion is not alleviated by providing ssb in trans. By altering expression of the ssb gene, we also show that lower levels of transcription are required for optimal growth than are necessary for high radiation resistance. When expression is reduced to that of E. coli, ionizing radiation resistance is similarly reduced. UV resistance is also decreased under low ssb transcript levels where growth is unimpaired. These results indicate that the expression of ssb is a key component of both normal cellular metabolism as well as pathways responsible for the high radiation tolerance of D. radiodurans.

  16. External Beam Radiotherapy of Recurrent Glioma: Radiation Tolerance of the Human Brain

    Energy Technology Data Exchange (ETDEWEB)

    Sminia, Peter, E-mail: p.sminia@vumc.nl [Department of Radiation Oncology, Radiobiology Section, VU University Medical Center, De Boelelaan 1117, P.O. Box 7057, Amsterdam (Netherlands); Mayer, Ramona [EBG MedAustron GmbH., Viktor Kaplan-Strasse 2, A-2700, Wiener Neustadt (Austria)

    2012-04-05

    Malignant gliomas relapse in close proximity to the resection site, which is the postoperatively irradiated volume. Studies on re-irradiation of glioma were examined regarding radiation-induced late adverse effects (i.e., brain tissue necrosis), to obtain information on the tolerance dose and treatment volume of normal human brain tissue. The studies were analyzed using the linear-quadratic model to express the re-irradiation tolerance in cumulative equivalent total doses when applied in 2 Gy fractions (EQD2{sub cumulative}). Analysis shows that the EQD2{sub cumulative} increases from conventional re-irradiation series to fractionated stereotactic radiotherapy (FSRT) to LINAC-based stereotactic radiosurgery (SRS). The mean time interval between primary radiotherapy and the re-irradiation course was shortened from 30 months for conventional re-irradiation to 17 and 10 months for FSRT and SRS, respectively. Following conventional re-irradiation, radiation-induced normal brain tissue necrosis occurred beyond an EQD2{sub cumulative} around 100 Gy. With increasing conformality of therapy, the smaller the treatment volume is, the higher the radiation dose that can be tolerated. Despite the dose escalation, no increase in late normal tissue toxicity was reported. On basis of our analysis, the use of particle therapy in the treatment of recurrent gliomas, because of the optimized physical dose distribution in the tumour and surrounding healthy brain tissue, should be considered for future clinical trials.

  17. Development of an ADC Radiation Tolerance Characterization System for the Upgrade of the ATLAS LAr Calorimeter

    CERN Document Server

    INSPIRE-00445642; Chen, Kai; Kierstead, James; Lanni, Francesco; Takai, Helio; Jin, Ge

    2016-01-01

    ATLAS LAr calorimeter will perform its Phase-I upgrade during the long shut down (LS2) in 2018, a new LAr Trigger Digitizer Board (LTDB) will be designed and installed. Several commercial-off-the-shelf (COTS) multichannel high-speed ADCs have been selected as possible backups of the radiation tolerant ADC ASICs for LTDB. In order to evaluate the radiation tolerance of these back up commercial ADCs, we developed an ADC radiation tolerance characterization system, which includes the ADC boards, data acquisition (DAQ) board, signal generator, external power supplies and a host computer. The ADC board is custom designed for different ADCs, which has ADC driver and clock distribution circuits integrated on board. The Xilinx ZC706 FPGA development board is used as DAQ board. The data from ADC are routed to the FPGA through the FMC (FPGA Mezzanine Card) connector, de-serialized and monitored by the FPGA, and then transmitted to the host computer through the Gigabit Ethernet. A software program has been developed wit...

  18. External Beam Radiotherapy of Recurrent Glioma: Radiation Tolerance of the Human Brain

    Directory of Open Access Journals (Sweden)

    Peter Sminia

    2012-04-01

    Full Text Available Malignant gliomas relapse in close proximity to the resection site, which is the postoperatively irradiated volume. Studies on re-irradiation of glioma were examined regarding radiation-induced late adverse effects (i.e., brain tissue necrosis, to obtain information on the tolerance dose and treatment volume of normal human brain tissue. The studies were analyzed using the linear-quadratic model to express the re-irradiation tolerance in cumulative equivalent total doses when applied in 2 Gy fractions (EQD2cumulative. Analysis shows that the EQD2cumulative increases from conventional re-irradiation series to fractionated stereotactic radiotherapy (FSRT to LINAC-based stereotactic radiosurgery (SRS. The mean time interval between primary radiotherapy and the re-irradiation course was shortened from 30 months for conventional re-irradiation to 17 and 10 months for FSRT and SRS, respectively. Following conventional re-irradiation, radiation-induced normal brain tissue necrosis occurred beyond an EQD2cumulative around 100 Gy. With increasing conformality of therapy, the smaller the treatment volume is, the higher the radiation dose that can be tolerated. Despite the dose escalation, no increase in late normal tissue toxicity was reported. On basis of our analysis, the use of particle therapy in the treatment of recurrent gliomas, because of the optimized physical dose distribution in the tumour and surrounding healthy brain tissue, should be considered for future clinical trials.

  19. Radiation tolerance in the fruit fly, Drosophila Melanogaster - effects of laboratory culturing and stages in life cycle

    International Nuclear Information System (INIS)

    Vas, Iril Prima; Naik, Pramila; Kumar, Vineeth; Naik, Prathima; Patil, Rajashekar K.

    2013-01-01

    Radiation induced damages are due to direct effect of radiation energy or through free radical generation. Recent studies suggest Drosophila to be a good animal model to study radiation tolerance. The present study on female Drosophila melanogaster was conducted to observe 1. Variations in larval and adult radiation tolerance 2. Variations in laboratory culture and field populations of Drosophila. Third instar larvae were exposed to gamma radiation of 6, 10, 20, 30, 40 and 50 Gy in gamma chamber GC 5000 (BRT, India). Larvae of flies collected from the field were reared for two generations in the lab before irradiation. The laboratory cultured files were from stocks that were maintained for more than 1000 generations. The larvae of field populations had higher survival rate at 51% as compared to 43% in case of cultured flies and thus more resistant. The III instar larval stage (lab culture) had a LD50 of 26 Gy as compared to LD 50 of 928 Gy in case of adult flies have ∼ 160 times higher tolerance compared to humans. Prolonged rearing comparable to 'domestication' might have induced reduction in tolerance. Larval stages have a lower tolerance than adults possibly due to higher metabolic rate. Adults are post-mitotic in nature with very low rate of cell division. This may contribute to higher tolerance. This however is in contradiction to studies of midge (Chironomous) where larvae also have higher tolerance. (author)

  20. 0.25μm radiation tolerant technology for space applications

    International Nuclear Information System (INIS)

    Haddad, N.; Brady, F.; Scott, T.; Yoder, J.

    1999-01-01

    Lockheed Martin federal systems has developed a state-of-the-art radiation tolerant 0,25 μm CMOS capability that is compatible with commercial foundries as well as radiation hardened fabrication. A technology test chip was designed, fabricated and evaluated for performance, power and radiation hardness in order to validate the methodology and evaluate the technology. Testing results show that -) the active transistor threshold shift is negligible for 0.25 μm CMOS, -) the hardened STI (shallow trench isolation) can support Mega-rad applications, and -) the holding voltage is well beyond the operating voltage of 2.5 V. This technology is intended to support high density, high performance and low power space applications

  1. Radiation tolerant fiber optic humidity sensors for High Energy Physics applications

    CERN Document Server

    Berruti, Gaia Maria; Cusano, Andrea

    This work is devoted to the development of fiber optic humidity sensors to be applied in high-energy physics applications and in particular in experiments currently running at CERN. The high radiation level resulting from the operation of the accelerator at full luminosity can cause serious performance deterioration of the silicon sensors which are responsible for the particle tracking. To increase their lifetime, the sensors must be kept cold at temperatures below 0 C. At such low temperatures, any condensation risk has to be prevented and a precise thermal and hygrometric control of the air filling and surrounding the tracker detector cold volumes is mandatory. The technologies proposed at CERN for relative humidity monitoring are mainly based on capacitive sensing elements which are not designed with radiation resistance characteristic. In this scenario, fiber optic sensors seem to be perfectly suitable. Indeed, the fiber itself, if properly selected, can tolerate a very high level of radiation, optical fi...

  2. The Radiation Tolerant Electronics for the LHC Cryogenic Controls: Basic Design and First Operational Experience

    CERN Document Server

    Casas-Cubillos, J; Rodríguez-Ruiz, M A

    2008-01-01

    The LHC optics is based in the extensive use of superconducting magnets covering 23 km inside the tunnel. The associated cryogenic system for keeping the magnets in nominal conditions is hence distributed all around the 27 km LHC tunnel and the cryogenic instrumentation submitted to the LHC radiation environment is composed of about 18’000 sensors and actuators. Radiation Tolerant (RadTol) electronics was designed and procured in order to keep the signals integrity against electromagnetic interference and to reduce cabling costs required in case of sending the analog signals into the 30 radiation protected areas. This paper presents the basic design, the qualification of the main RadTol components and the first operational results.

  3. Iso-effect table for radiation tolerance of the human spinal cord

    International Nuclear Information System (INIS)

    Cohen, L.; Creditor, M.

    1981-01-01

    Available literature on radiation injury to the human spinal cord was collected into a comprehensive data set relating the incidence of myelopathy to dosage, number of fractions and total treatment time. The data was analyzed using a search program (RAD3) to derive best-fitting cell kinetic parameters on the assumption that radiation myelopathy arises from cellular depletion in the irradiated tissues. From these parameters iso-effect tables were constructed for a wide range of treatment schedules, including daily treatment as well as fractionation at longer intervals. The tables provide a set of limiting doses, above which the risk of radiation injury to the spinal cord becomes substantial. General application of NSD tolerance limits could lead to systematic overdosage of the spinal cord, especially with large individual fractions or short treatment times. We conclude that the computed iso-effect tables provide a more reliable clinical guide than conventional time-dose equations

  4. Late effects of radiation on the lumbar spinal cord of guinea pigs: Re-treatment tolerance

    International Nuclear Information System (INIS)

    Mason, K.A.; Withers, H.R.; Chiang, Chi-Shiun

    1993-01-01

    Using a guinea pig model of lumbar myelopathy, various factors affecting the tolerance of spinal cord to irradiation were assessed: (a) extent of initial injury; (b) time interval between priming and test doses; and (c) animal age at the time of initial radiation treatment. A 3 cm section of lumbar spinal cord of guinea pigs was irradiated with fractionated doses of 4.5 Gy gamma rays given as 9 fractions per week. Guinea pigs were primed with 9 x 4.5 Gy in 7 days which is 60% of the ED 50 for a continuous course of treatment. After 28 or 40 weeks, animal were retreated with 6-14 fractions of 4.5 Gy. Animals were observed for 2 years following the priming dose and both the incidence and latency of myelopathy recorded. Young adult guinea pigs (8 wk old) showed both a decreased radiation tolerance and latency compared to old individuals (40 wk old). At 28 or 40 wk after 9 x 4.5 Gy, only about 8% of the initial injury was remembered in young adult guinea pigs. The amount of residual injury was dependent on the initial damage as a proportion of the tolerance dose. The spinal cord shows a greater capacity for long-term recovery than generally appreciated and re-treatment doses clinically prescribed may be lower than necessary. 8 refs., 3 figs., 2 tabs

  5. Studies on the mechanism of stable graft--host tolerance in canine and human radiation chimeras

    International Nuclear Information System (INIS)

    Storb, R.; Tsoi, M.S.; Weiden, P.L.; Graham, T.C.; Thomas, E.D.

    1976-01-01

    In studies with dogs, marrow donors were immunized against their chimeras by repeated skin grafts which they rejected. Lymphocytes from chimeras and donors were tested for cell inhibition by exposure to skin fibroblasts from chimeras and donors. Results were not compatible with the concept that tolerance in radiation chimeras is maintained by serum-blocking factors. They provide circumstantial evidence against the possibility that the stable chimeric state is the result of the deletion of a close or inactivation of donor lymphocytes specifically responsive for host antigens. They are most consistent with the possibility that a suppressor-cell population is responsible for the maintenance of tolerance. Human recipients of marrow transplants were tested with the cell inhibition assay. Although the incidence of positive cell inhibition and blocking was somewhat higher than in the dog, results were not compatible with the concept that serum blocking is the sole mechanism for maintaining the stable chimeric state in human patients

  6. Radiation-tolerant cable management systems for remote handling applications in the nuclear industry

    International Nuclear Information System (INIS)

    Cullen, S.; Thom, M.

    1993-01-01

    Experience has shown that one of the most vulnerable areas within remote handling equipment is the umbilical cable and termination system. Repairs of a damaged system can be very long due to poorly designed termination techniques. Over the past five years W.L. Gore has gained considerable experience in the design and manufacture of cable systems, utilising unique radiation tolerant materials and manufacturing processes. The cable systems manufactured at the W.L. Gore, Dunfermline, Scotland facility have proven to give excellent performance in the most demanding of remote handling applications. (author)

  7. ARTIST: advanced radiation-tolerant information and sensor system for teleoperation

    International Nuclear Information System (INIS)

    Schmidt, D.; Pathe, V.; Ostertag, M.; Dittrich, F.; Dumbreck, A.; Sirat, G.; Katzouraki, M.

    1993-01-01

    ARTIST integrates a stereoscopic camera and a rangefinder as sensor package into a high-precision pan-and-tilt head and represents the recorded data in a clear and comprehensive way for telemanipulation and control tasks as well as for remote driving. The sensors as well as the pan-and-tilt head are radiation-tolerant so they can be used in nuclear environments. The pan-and-tilt head and work station are completely configured and developed with the emphasis on multisensor integration, real-time video processing and graphical position representation. An efficient man-machine-interface appropriate software is included. (author)

  8. Development of radiation tolerant components for the Quench Protection System at CERN

    Science.gov (United States)

    Bitterling, O.; Denz, R.; Steckert, J.; Uznanski, S.

    2016-01-01

    This paper describes the results of irradiation campaigns with the high resolution Analog to Digital Converter (ADC) ADS1281. This ADC will be used as part of a revised quench detection circuit for the 600 A corrector magnets at the CERN Large Hadron Collider (LHC) . To verify the radiation tolerance of the ADC an irradiation campaign using a proton beam, applying doses up to 3,4 kGy was conducted. The resulting data and an analysis of the found failure modes is discussed in this paper. Several mitigation measures are described that allow to reduce the error rate to levels acceptable for operation as part of the LHC QPS.

  9. Development of radiation tolerant components for the Quench Protection System at CERN

    International Nuclear Information System (INIS)

    Bitterling, O.; Denz, R.; Steckert, J.; Uznanski, S.

    2016-01-01

    This paper describes the results of irradiation campaigns with the high resolution Analog to Digital Converter (ADC) ADS1281. This ADC will be used as part of a revised quench detection circuit for the 600 A corrector magnets at the CERN Large Hadron Collider (LHC) . To verify the radiation tolerance of the ADC an irradiation campaign using a proton beam, applying doses up to 3,4 kGy was conducted. The resulting data and an analysis of the found failure modes is discussed in this paper. Several mitigation measures are described that allow to reduce the error rate to levels acceptable for operation as part of the LHC QPS

  10. Design of Radiation-Tolerant Structural Alloys for Generation IV Nuclear Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Allen, T.R.; Was, G.S.; Bruemmer, S.M.; Gan, J.; Ukai, S.

    2005-12-28

    The objective of this program is to improve the radiation tolerance of both austenitic and ferritic-martensitic (F-M) alloys projected for use in Generation IV systems. The expected materials limitations of Generation IV components include: creep strength, dimensional stability, and corrosion/stress corrosion compatibility. The material design strategies to be tested fall into three main categories: (1) engineering grain boundaries; (2) alloying, by adding oversized elements to the matrix; and (3) microstructural/nanostructural design, such as adding matrix precipitates. These three design strategies were tested across both austenitic and ferritic-martensitic alloy classes

  11. Gamma radiation tolerance in different life stages of the fruit fly Drosophila melanogaster.

    Science.gov (United States)

    Paithankar, Jagdish Gopal; Deeksha, K; Patil, Rajashekhar K

    2017-04-01

    Insects are known to have higher levels of radiation tolerance than mammals. The fruit fly Drosophila provides opportunities for genetic analysis of radiation tolerance in insects. A knowledge of stage-specific sensitivity is required to understand the mechanisms and test the existing hypothesis of insect radiation tolerance. Drosophila melanogaster were irradiated using gamma rays at different life stages. Irradiation doses were chosen to start from 100-2200 Gy with increments of 100 Gy, with a dose rate of 12.5 and 25 Gy/min. The threshold of mortality, LD 50 and LD 100 1 h post-irradiation was recorded for larvae and adults and 24 h post-irradiation for eggs and after 2-3 days for early and late pupae. Total antioxidant capacity for all the life stages was measured using the phosphomolybdenum method. Twenty-four hours post-irradiation, 100% mortality was recorded for eggs at 1000 Gy. One hour post irradiation 100% mortality was recorded at 1300 Gy for first instar larvae, 1700 Gy for second instar larvae, 1900 Gy for feeding third instar larvae and 2200 Gy for non-feeding third instar larvae. Post-irradiation complete failure of emergence (100% mortality) was observed at 130 Gy for early pupae and 1500 Gy for late pupae; 100% mortality was observed at 1500 Gy for adults. The values of LD 50 were recorded as 452 Gy for eggs, 1049 Gy for first instar larvae, 1350 Gy for second instar larvae, 1265 Gy for feeding third instar larvae, 1590 Gy for non-feeding third instar larvae, 50 Gy for early pupae, 969 Gy for late pupae, 1228 Gy for adult males and 1250 Gy for adult females. Early pupae were found to be prone to radiation, whereas the non-feeding third instar larvae were most resistant among all stages. The chromosome number being constant and total antioxidant capacity being nearly constant in all stages, we suggest that high rate of cell division during early pupae makes this stage sensitive to radiation.

  12. Role of interfaces i nthe design of ultra-high strength, radiation damage tolerant nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Nastasi, Michael A [Los Alamos National Laboratory; Baldwin, Jon K [Los Alamos National Laboratory; Wei, Qiangmin [Los Alamos National Laboratory; Li, Nan [Los Alamos National Laboratory; Mara, Nathan [Los Alamos National Laboratory; Zhang, Xinghang [Los Alamos National Laboratory; Fu, Engang [Los Alamos National Laboratory; Anderoglu, Osman [Los Alamos National Laboratory; Li, Hongqi [Los Alamos National Laboratory; Bhattacharyya, Dhriti [NON LANL

    2010-12-09

    The combination of high strength and high radiation damage tolerance in nanolaminate composites can be achieved when the individual layers in these composites are only a few nanometers thick and contain special interfaces that act both as obstacles to slip, as well as sinks for radiation-induced defects. The morphological and phase stabilities and strength and ductility of these nano-composites under ion irradiation are explored as a function of layer thickness, temperature and interface structure. Magnetron sputtered metallic multilayers such as Cu-Nb and V-Ag with a range of individual layer thickness from approximately 2 nm to 50 nm and the corresponding 1000 nm thick single layer films were implanted with helium ions at room temperature. Cross-sectional Transmission Electron Microscopy (TEM) was used to measure the distribution of helium bubbles and correlated with the helium concentration profile measured vis ion beam analysis techniques to obtain the helium concentration at which bubbles are detected in TEM. It was found that in multilayers the minimum helium concentration to form bubbles (approximately I nm in size) that are easily resolved in through-focus TEM imaging was several atomic %, orders of magnitude higher than that in single layer metal films. This observation is consistent with an increased solubility of helium at interfaces that is predicted by atomistic modeling of the atomic structures of fcc-bcc interfaces. At helium concentrations as high as 7 at.%, a uniform distribution of I nm diameter bubbles results in negligible irradiation hardening and loss of deformability in multi layers with layer thicknesses of a few nanometers. The control of atomic structures of interfaces to produce high helium solubility at interfaces is crucial in the design of nano-composite materials that are radiation damage tolerant. Reduced radiation damage also leads to a reduction in the irradiation hardening, particularly at layer thickness of approximately 5 run

  13. Application of organ tolerance dose-constraints in clinical studies in radiation oncology

    Energy Technology Data Exchange (ETDEWEB)

    Doerr, Wolfgang [Medical University/AKH Vienna, Dept. of Radiation Oncology/Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Comprehensive Cancer Center, Vienna (Austria); Technical University Dresden, Department of Radiotherapy and Radiation Oncology, OncoRay-National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Dresden (Germany); Task Group ' ' Tolerance Doses' ' of the German Society for Radiation Oncology (DEGRO), Berlin (Germany); Herrmann, Thomas [Task Group ' ' Tolerance Doses' ' of the German Society for Radiation Oncology (DEGRO), Berlin (Germany); Baumann, Michael [Technical University Dresden, Department of Radiotherapy and Radiation Oncology, OncoRay-National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Dresden (Germany); Task Group ' ' Tolerance Doses' ' of the German Society for Radiation Oncology (DEGRO), Berlin (Germany)

    2014-07-15

    In modern radiation oncology, tolerance dose-constraints for organs at risk (OAR) must be considered for treatment planning, but particularly in order to design clinical studies. Tolerance dose tables, however, only address one aspect of the therapeutic ratio of any clinical study, i.e., the limitation of adverse events, but not the desired potential improvement in the tumor effect of a novel treatment strategy. A sensible application of ''tolerance doses'' in a clinical situation requires consideration of various critical aspects addressed here: definition of tolerance dose, specification of an endpoint/symptom, consideration of radiation quality and irradiation protocol, exposed volume and dose distribution, and patient-related factors of radiosensitivity. The currently most comprehensive estimates of OAR radiation tolerance are in the QUANTEC compilations (2010). However, these tolerance dose values must only be regarded as a rough orientation and cannot answer the relevant question for the patients, i.e., if the study can achieve a therapeutic advantage; this can obviously be answered only by the final scientific analysis of the study results. Despite all limitations, the design of clinical studies should currently refer to the QUANTEC values for appreciation of the risk of complications, if needed supplemented by one's own data or further information from the literature. The implementation of a consensus on the safety interests of the patients and on an application and approval process committed to progress in medicine, with transparent quality-assuring requirements with regard to the structural safeguarding of the study activities, plays a central role in clinical research in radiation oncology. (orig.) [German] In der modernen Radioonkologie muessen Toleranzdosisgrenzen fuer die Risikoorgane (''organs at risk'', OAR) zur Behandlungsplanung, besonders aber zur Gestaltung klinischer Studien, herangezogen werden

  14. Spectroscopic investigation of ionizing-radiation tolerance of a Chlorophyceae green micro-alga

    Energy Technology Data Exchange (ETDEWEB)

    Farhi, E; Compagnon, E; Marzloff, V; Ollivier, J; Boisson, A M; Natali, F; Russo, D [Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9 (France); Rivasseau, C; Gromova, M; Bligny, R [CEA, Laboratoire de Physiologie Cellulaire Vegetale, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France); Coute, A [Museum National d' Histoire Naturelle, Laboratoire de Cryptogamie, 2 rue Buffon, 75005 Paris (France)

    2008-03-12

    Micro-organisms living in extreme environments are captivating in the peculiar survival processes they have developed. Deinococcus radiodurans is probably the most famous radio-resistant bacteria. Similarly, a specific ecosystem has grown in a research reactor storage pool, and has selected organisms which may sustain radiative stress. An original green micro-alga which was never studied for its high tolerance to radiations has been isolated. It is the only autotrophic eukaryote that develops in this pool, although contamination possibilities coming from outside are not unusual. Studying what could explain this irradiation tolerance is consequently very interesting. An integrative study of the effects of irradiation on the micro-algae physiology, metabolism, internal dynamics, and genomics was initiated. In the work presented here, micro-algae were stressed with irradiation doses up to 20 kGy (2 Mrad), and studied by means of nuclear magnetic resonance, looking for modifications in the metabolism, and on the IN13 neutron backscattering instrument at the ILL, looking for both dynamics and structural macromolecular changes in the cells.

  15. Spectroscopic investigation of ionizing-radiation tolerance of a Chlorophyceae green micro-alga

    International Nuclear Information System (INIS)

    Farhi, E; Compagnon, E; Marzloff, V; Ollivier, J; Boisson, A M; Natali, F; Russo, D; Rivasseau, C; Gromova, M; Bligny, R; Coute, A

    2008-01-01

    Micro-organisms living in extreme environments are captivating in the peculiar survival processes they have developed. Deinococcus radiodurans is probably the most famous radio-resistant bacteria. Similarly, a specific ecosystem has grown in a research reactor storage pool, and has selected organisms which may sustain radiative stress. An original green micro-alga which was never studied for its high tolerance to radiations has been isolated. It is the only autotrophic eukaryote that develops in this pool, although contamination possibilities coming from outside are not unusual. Studying what could explain this irradiation tolerance is consequently very interesting. An integrative study of the effects of irradiation on the micro-algae physiology, metabolism, internal dynamics, and genomics was initiated. In the work presented here, micro-algae were stressed with irradiation doses up to 20 kGy (2 Mrad), and studied by means of nuclear magnetic resonance, looking for modifications in the metabolism, and on the IN13 neutron backscattering instrument at the ILL, looking for both dynamics and structural macromolecular changes in the cells

  16. A Multi-Environment Thermal Control System With Freeze-Tolerant Radiator

    Science.gov (United States)

    Chen, Weibo; Fogg, David; Mancini, Nick; Steele, John; Quinn, Gregory; Bue, Grant; Littibridge, Sean

    2013-01-01

    Future space exploration missions require advanced thermal control systems (TCS) to dissipate heat from spacecraft, rovers, or habitats operating in environments that can vary from extremely hot to extremely cold. A lightweight, reliable TCS is being developed to effectively control cabin and equipment temperatures under widely varying heat loads and ambient temperatures. The system uses freeze-tolerant radiators, which eliminate the need for a secondary circulation loop or heat pipe systems. Each radiator has a self-regulating variable thermal conductance to its ambient environment. The TCS uses a nontoxic, water-based working fluid that is compatible with existing lightweight aluminum heat exchangers. The TCS is lightweight, compact, and requires very little pumping power. The critical characteristics of the core enabling technologies were demonstrated. Functional testing with condenser tubes demonstrated the key operating characteristics required for a reliable, freeze-tolerant TCS, namely (1) self-regulating thermal conductance with short transient responses to varying thermal loads, (2) repeatable performance through freeze-thaw cycles, and (3) fast start-up from a fully frozen state. Preliminary coolant tests demonstrated that the corrosion inhibitor in the water-based coolant can reduce the corrosion rate on aluminum by an order of magnitude. Performance comparison with state-of-the-art designs shows significant mass and power saving benefits of this technology.

  17. Tolerance to Gamma Radiation in the Tardigrade Hypsibius dujardini from Embryo to Adult Correlate Inversely with Cellular Proliferation.

    Directory of Open Access Journals (Sweden)

    Eliana Beltrán-Pardo

    Full Text Available Tardigrades are highly tolerant to desiccation and ionizing radiation but the mechanisms of this tolerance are not well understood. In this paper, we report studies on dose responses of adults and eggs of the tardigrade Hypsibius dujardini exposed to gamma radiation. In adults the LD50/48h for survival was estimated at ~ 4200 Gy, and doses higher than 100 Gy reduced both fertility and hatchability of laid eggs drastically. We also evaluated the effect of radiation (doses 50 Gy, 200 Gy, 500 Gy on eggs in the early and late embryonic stage of development, and observed a reduced hatchability in the early stage, while no effect was found in the late stage of development. Survival of juveniles from irradiated eggs was highly affected by a 500 Gy dose, both in the early and the late stage. Juveniles hatched from eggs irradiated at 50 Gy and 200 Gy developed into adults and produced offspring, but their fertility was reduced compared to the controls. Finally we measured the effect of low temperature during irradiation at 4000 Gy and 4500 Gy on survival in adult tardigrades, and observed a slight delay in the expressed mortality when tardigrades were irradiated on ice. Since H. dujardini is a freshwater tardigrade with lower tolerance to desiccation compared to limno-terrestrial tardigrades, the high radiation tolerance in adults, similar to limno-terrestrial tardigrades, is unexpected and seems to challenge the idea that desiccation and radiation tolerance rely on the same molecular mechanisms. We suggest that the higher radiation tolerance in adults and late stage embryos of H. dujardini (and in other studied tardigrades compared to early stage embryos may partly be due to limited mitotic activity, since tardigrades have a low degree of somatic cell division (eutely, and dividing cells are known to be more sensitive to radiation.

  18. Normal tissue tolerance to external beam radiation therapy: The stomach; Dose de tolerance a l'irradiation des tissus sains: l'estomac

    Energy Technology Data Exchange (ETDEWEB)

    Oberdiac, P. [Service de radiotherapie, hopital de Bellevue, CHU de Saint-Etienne, 42 - Saint-Etienne (France); Mineur, L. [Unite d' oncologie digestive et radiotherapie, institut Sainte-Catherine, 84 - Avignon (France)

    2010-07-15

    In the following article, we will discuss general issues relating to acute and late gastric's radiation toxicities. The tolerance of the stomach to complete or partial organ irradiation is more un-appreciated than for most other organs. We consulted the Medline database via PubMed and used the key words gastric - radiotherapy - toxicity. Currently, 60 Gy or less is prescribed in gastric radiation therapy. Acute clinical toxicity symptoms are predominantly nausea and vomiting. Although there is a general agreement that the whole stomach tolerance is for doses of 40 to 45 Gy without unacceptable complication, it is well established that a stomach dose of 35 Gy increases the risk of ulcer complications. (authors)

  19. 40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests

    Science.gov (United States)

    2010-07-01

    ... Permitted Tolerance for Conducting Radiative Tests E Table E-2 to Subpart E of Part 53 Protection of... Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 Pt. 53, Subpt. E, Table E-2 Table E-2 to Subpart E of Part 53—Spectral Energy Distribution and Permitted Tolerance for...

  20. The Xenon Test Chamber Q-SUN® for testing realistic tolerances of fungi exposed to simulated full spectrum solar radiation.

    Science.gov (United States)

    Dias, Luciana P; Araújo, Claudinéia A S; Pupin, Breno; Ferreira, Paulo C; Braga, Gilberto Ú L; Rangel, Drauzio E N

    2018-06-01

    The low survival of insect-pathogenic fungi when used for insect control in agriculture is mainly due to the deleterious effects of ultraviolet radiation and heat from solar irradiation. In this study, conidia of 15 species of entomopathogenic fungi were exposed to simulated full-spectrum solar radiation emitted by a Xenon Test Chamber Q-SUN XE-3-HC 340S (Q-LAB ® Corporation, Westlake, OH, USA), which very closely simulates full-spectrum solar radiation. A dendrogram obtained from cluster analyses, based on lethal time 50 % and 90 % calculated by Probit analyses, separated the fungi into three clusters: cluster 3 contains species with highest tolerance to simulated full-spectrum solar radiation, included Metarhizium acridum, Cladosporium herbarum, and Trichothecium roseum with LT 50  > 200 min irradiation. Cluster 2 contains eight species with moderate UV tolerance: Aschersonia aleyrodis, Isaria fumosorosea, Mariannaea pruinosa, Metarhizium anisopliae, Metarhizium brunneum, Metarhizium robertsii, Simplicillium lanosoniveum, and Torrubiella homopterorum with LT 50 between 120 and 150 min irradiation. The four species in cluster 1 had the lowest UV tolerance: Lecanicillium aphanocladii, Beauveria bassiana, Tolypocladium cylindrosporum, and Tolypocladium inflatum with LT 50  solar radiation before. We conclude that the equipment provided an excellent tool for testing realistic tolerances of fungi to full-spectrum solar radiation of microbial agents for insect biological control in agriculture. Copyright © 2018 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  1. Acute radiation reactions in oral and pharyngeal mucosa: tolerable levels in altered fractionation schedules

    International Nuclear Information System (INIS)

    Fowler, Jack F.; Harari, Paul M.; Leborgne, Felix; Leborgne, Jose H.

    2003-01-01

    by up to roughly 3-5 Gy10 in BED, with a request for further evidence. Conclusions:It is suggested that total BED should be used, as specified above. Parameters of α=0.35 Gy- 1 , α/β=10 Gy, Tk=7 days and Tp=2.5 days are suggested. The 'acute/ tolerance zone' then turns out to be 59-61 Gy10 for radiation-only treatments. Further information about the decrement caused by concurrent head-and-neck cancer chemoradiotherapy, possibly 3-5 Gy10, is required

  2. Lightweight Damage Tolerant, High-Temperature Radiators for Nuclear Power and Propulsion

    Science.gov (United States)

    Craven, Paul D.; SanSoucie, Michael P.

    2015-01-01

    NASA is increasingly emphasizing exploration to bodies beyond near-Earth orbit. New propulsion systems and new spacecraft are being built for these missions. As the target bodies get further out from Earth, high energy density systems, e.g., nuclear fusion, for propulsion and power will be advantageous. The mass and size of these systems, including supporting systems such as the heat exchange system, including thermal radiators, will need to be as small as possible. Conventional heat exchange systems are a significant portion of the total thermal management mass and size. Nuclear electric propulsion (NEP) is a promising option for high-speed, in-space travel due to the high energy density of nuclear fission power sources and efficient electric thrusters. Heat from the reactor is converted to power for use in propulsion or for system power. The heat not used in the power conversion is then radiated to space as shown in figure 1. Advanced power conversion technologies will require high operating temperatures and would benefit from lightweight radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature, thermal conductivity, and mass. These properties combine to allow significant decreases in the total mass of the radiators and significant increases in the operating temperature of the fins. A Center-funded project at NASA Marshall Space Flight Center has shown that high thermal conductivity, woven carbon fiber fins with no matrix material, can be used to dissipate waste heat from NEP systems and because of high specific power (kW/kg), will require less mass and possibly less total area than standard metal and composite radiator fins for radiating the same amount of heat. This project uses an innovative approach to reduce the mass and size required for the thermal radiators to the point that in-space NEP and power

  3. Enhanced radiation tolerance of ultrafine grained Fe–Cr–Ni alloy

    International Nuclear Information System (INIS)

    Sun, C.; Yu, K.Y.; Lee, J.H.; Liu, Y.; Wang, H.; Shao, L.; Maloy, S.A.; Hartwig, K.T.; Zhang, X.

    2012-01-01

    Highlights: ► Ultrafine grained Fe-Cr-Ni alloy was processed by equal channel angular pressing technique. ► The overall Helium bubble density and dislocation loop density were reduced by grain refinement. ► The ultrafine grained microstructure alleviated radiation-induced hardening. - Abstract: The evolutions of microstructure and mechanical properties of Fe–14Cr–16Ni (wt.%) alloy subjected to Helium ion irradiations were investigated. Equal channel angular pressing (ECAP) process was used to significantly reduce the average grain size from 700 μm to 400 nm. At a peak fluence level of 5.5 displacement per atom (dpa), helium bubbles, 0.5–2 nm in diameter, were observed in both coarse-grained (CG) and ultrafine grained (UFG) alloy. The density of He bubbles, dislocation loops, as well as radiation hardening were reduced in the UFG Fe–Cr–Ni alloy comparing to those in its CG counterpart. The results imply that radiation tolerance in bulk metals can be effectively enhanced by refinement of microstructures.

  4. Development of radiation tolerant semiconductor detectors for the Super-LHC

    CERN Document Server

    Moll, M; Al-Ajili, A A; Alfieri, G; Allport, P P; Artuso, M; Assouak, S; Avset, B S; Barabash, L; Barcz, A; Bates, R; Biagi, S F; Bilei, G M; Bisello, D; Blue, A; Blumenau, A; Boisvert, V; Bölla, G; Bondarenko, G B; Borchi, E; Borrello, L; Bortoletto, D; Boscardin, M; Bosisio, L; Bowcock, T J V; Brodbeck, T J; Broz, J; Bruzzi, M; Brzozowski, A; Buda, M; Buhmann, P; Buttar, C; Campabadal, F; Campbell, D; Candelori, A; Casse, G; Cavallini, A; Charron, S; Chilingarov, A; Chren, D; Cindro, V; Collins, P; Coluccia, R; Contarato, D; Coutinho, J; Creanza, D; Cunningham, W; Betta, G F D; Dawson, I; de Boer, Wim; De Palma, M; Demina, R; Dervan, P; Dittongo, S; Dolezal, Z; Dolgolenko, A; Eberlein, T; Eremin, V; Fall, C; Fasolo, F; Fizzotti, F; Fleta, C; Focardi, E; Forton, E; Fretwurst, E; García, C; García-Navarro, J E; Gaubas, E; Genest, M H; Gill, K A; Giolo, K; Glaser, M; Gössling, C; Golovine, V; Sevilla, S G; Gorelov, I; Goss, J; Bates, A G; Grégoire, G; Gregori, P; Grigoriev, E; Grillo, A A; Groza, A; Guskov, J; Haddad, L; Härkönen, J; Hauler, F; Hoeferkamp, M; Honniger, F; Horazdovsky, T; Horisberger, Roland Paul; Horn, M; Houdayer, A; Hourahine, B; Hughes, G; Ilyashenko, Yu S; Irmscher, K; Ivanov, A; Jarasiunas, K; Johansen, K M H; Jones, B K; Jones, R; Joram, C; Jungermann, L; Kalinina, E; Kaminski, P; Karpenko, A; Karpov, A; Kazlauskiene, V; Kazukauskas, V; Khivrich, V; Khomenkov, V; Kierstead, J A; Klaiber Lodewigs, J; Klingenberg, R; Kodys, P; Kohout, Z; Korjenevski, S; Koski, M; Kozlowski, R; Kozodaev, M; Kramberger, G; Krasel, O; Kuznetsov, A; Kwan, S; Lagomarsino, S; Lassila-Perini, K M; Lastovetsky, V F; Latino, G; Lazanu, S; Lazanu, I; Lebedev, A; Lebel, C; Leinonen, K; Leroy, C; Li Z; Lindström, G; Linhart, V; Litovchenko, A P; Litovchenko, P G; Lo Giudice, A; Lozano, M; Luczynski, Z; Luukka, P; Macchiolo, A; Makarenko, L F; Mandic, I; Manfredotti, C; Manna, N; Garcia, S Mi; Marunko, S; Mathieson, K; Melone, J; Menichelli, D; Messineo, A; Metcalfe, J; Miglio, S; Mikuz, M; Miyamoto, J; Monakhov, E; Moscatelli, F; Naoumov, D; Nossarzhevska, E; Nysten, J; Olivero, P; OShea, V; Palviainen, T; Paolini, C; Parkes, C; Passeri, D; Pein, U; Pellegrini, G; Perera, L; Petasecca, M; Piemonte, C; Pignatel, G U; Pinho, N; Pintilie, I; Pintilie, L; Polivtsev, L; Polozov, P; Popa, A; Popule, J; Pospísil, S; Pozza, A; Radicci, V; Rafí, J M; Rando, R; Röder, R; Rohe, T; Ronchin, S; Rott, C; Roy, A; Ruzin, A; Sadrozinski, H F W; Sakalauskas, S; Scaringella, M; Schiavulli, L; Schnetzer, S; Schumm, B; Sciortino, S; Scorzoni, A; Segneri, G; Seidel, S; Seiden, A; Sellberg, G; Sellin, P J; Sentenac, D; Shipsey, I; Sícho, P; Sloan, T; Solar, M; Son, S; Sopko, B; Sopko, V; Spencer, N; Stahl, J; Stolze, D; Stone, R; Storasta, J; Strokan, N; Sudzius, M; Surma, B; Suvorov, A; Svensson, B G; Tipton, P; Tomasek, M; Tsvetkov, A; Tuominen, E; Tuovinen, E; Tuuva, T; Tylchin, M; Uebersee, H; Uher, J; Ullán, M; Vaitkus, J V; Velthuis, J; Verbitskaya, E; Vrba, V; Wagner, G; Wilhelm, I; Worm, S; Wright, V; Wunstorf, R; Yiuri, Y; Zabierowski, P; Zaluzhny, A; Zavrtanik, M; Zen, M; Zhukov, V; Zorzi, N

    2005-01-01

    The envisaged upgrade of the Large Hadron Collider (LHC) at CERN towards the Super-LHC (SLHC) with a 10 times increased luminosity of 10challenges for the tracking detectors of the SLHC experiments. Unprecedented high radiation levels and track densities and a reduced bunch crossing time in the order of 10ns as well as the need for cost effective detectors have called for an intensive R&D program. The CERN RD50 collaboration "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" is working on the development of semiconductor sensors matching the requirements of the SLHC. Sensors based on defect engineered silicon like Czochralski, epitaxial and oxygen enriched silicon have been developed. With 3D, Semi-3D and thin detectors new detector concepts have been evaluated and a study on the use of standard and oxygen enriched p-type silicon detectors revealed a promising approach for radiation tolerant cost effective devices. These and other most recent advancements of the RD50 ...

  5. Evaluation of testing strategies for the radiation tolerant ATLAS n **+-in-n pixel sensor

    CERN Document Server

    Klaiber Lodewigs, Jonas M

    2003-01-01

    The development of particle tracker systems for high fluence environments in new high-energy physics experiments raises new challenges for the development, manufacturing and reliable testing of radiation tolerant components. The ATLAS pixel detector for use at the LHC, CERN, is designed to cover an active sensor area of 1.8 m**2 with 1.1 multiplied by 10 **8 read-out channels usable for a particle fluence up to 10 **1**5 cm**-**2 (1 MeV neutron equivalent) and an ionization dose up to 500 kGy of mainly charged hadron radiation. To cope with such a harsh environment the ATLAS Pixel Collaboration has developed a radiation hard n **+-in-n silicon pixel cell design with a standard cell size of 50 multiplied by 400 mum**2. Using this design on an oxygenated silicon substrate, sensor production has started in 2001. This contribution describes results gained during the development of testing procedures of the ATLAS pixel sensor and evaluates quality assurance procedures regarding their relevance for detector operati...

  6. Tolerance doses of cutaneous and mucosal tissues in ring-necked parakeets (Psittacula krameri) for external beam megavoltage radiation.

    Science.gov (United States)

    Barron, Heather W; Roberts, Royce E; Latimer, Kenneth S; Hernandez-Divers, Stephen; Northrup, Nicole C

    2009-03-01

    Currently used dosages for external-beam megavoltage radiation therapy in birds have been extrapolated from mammalian patients and often appear to provide inadequate doses of radiation for effective tumor control. To determine the tolerance doses of cutaneous and mucosal tissues of normal birds in order to provide more effective radiation treatment for tumors that have been shown to be radiation responsive in other species, ingluvial mucosa and the skin over the ingluvies of 9 ring-necked parakeets (Psittacula krameri) were irradiated in 4-Gy fractions to a total dose of either 48, 60, or 72 Gy using an isocentric cobalt-60 teletherapy unit. Minimal radiation-induced epidermal changes were present in the high-dose group histologically. Neither dose-related acute nor chronic radiation effects could be detected in any group grossly in cutaneous or mucosal tissue over a 9-month period. Radiation doses of 72 Gy in 4-Gy fractions were well tolerated in the small number of ring-necked parakeets in this initial tolerance dose study.

  7. Development of inspection equipment for fuel bundles of CANDU-PHWR using R981 underwater radiation tolerant camera

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Dae-Seo; Cho, Moon-Sung; Jo, Chang-Keun; Jun, Ji-Su; Jung, Jong Yeob; Park, Kwang-June; Suk, Ho-Chun

    2005-03-15

    The inspection equipment of fuel bundles was developed, which could perform visual inspection and dimensional measurement on fuel bundles of CANDU-PHWR, to evaluate, analyze the defective behavior of fuel bundles and inner surface of pressure tubes of inherent two-phase flow over 24kg/s in CANDU-6. The R981 radiation tolerant camera system with pan and tilt function was ordered and manufactured, which was waterproof, shielding radiation in underwater 10m in depth. The performance test, of the system ,due to camera-object distance was carried out in air/underwater atmosphere. The results of performance test of R981 radiation tolerant camera system are good. The inspection equipment of fuel bundles using R981 radiation tolerant camera system and underwater-radiation tolerant LVDT sensor(D5/200AW) was fabricated, which could perform visual inspection and dimensional measurement on fuel bundles of CANDU-PHWR with measurement accuracy 10{mu}m. This equipment will be utilizable integrity evaluation of fuel bundles which are irradiated in pressure tube of CANDU-PHWR.

  8. Aspect Ratio Model for Radiation-Tolerant Dummy Gate-Assisted n-MOSFET Layout.

    Science.gov (United States)

    Lee, Min Su; Lee, Hee Chul

    2014-01-01

    In order to acquire radiation-tolerant characteristics in integrated circuits, a dummy gate-assisted n-type metal oxide semiconductor field effect transistor (DGA n-MOSFET) layout was adopted. The DGA n-MOSFET has a different channel shape compared with the standard n-MOSFET. The standard n-MOSFET has a rectangular channel shape, whereas the DGA n-MOSFET has an extended rectangular shape at the edge of the source and drain, which affects its aspect ratio. In order to increase its practical use, a new aspect ratio model is proposed for the DGA n-MOSFET and this model is evaluated through three-dimensional simulations and measurements of the fabricated devices. The proposed aspect ratio model for the DGA n-MOSFET exhibits good agreement with the simulation and measurement results.

  9. Radiation tolerance study of a commercial 65 nm CMOS technology for high energy physics applications

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Lili, E-mail: lili03.ding@gmail.com [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); State Key Laboratory of Pulsed Radiation Simulation and Effect, Northwest Institute of Nuclear Technology, Xi' an (China); Gerardin, Simone [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); Bagatin, Marta [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); Bisello, Dario [Department of Physics and Astronomy, Padova University, Via Marzolo 8, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); Mattiazzo, Serena [Department of Physics and Astronomy, Padova University, Via Marzolo 8, 35131 Padova (Italy); Paccagnella, Alessandro [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy)

    2016-09-21

    This paper reports the radiation tolerance study of a commercial 65 nm technology, which is a strong candidate for the Large Hadron Collider applications. After exposure to 3 MeV protons till 1 Grad dose, the 65 nm CMOS transistors, especially the pMOSFETs, showed severe long-term degradation mainly in the saturation drain currents. There were some differences between the degradation levels in the nMOSFETs and the pMOSFETs, which were likely attributed to the positive charges trapped in the gate spacers. After exposure to heavy ions till multiple strikes, the pMOSFETs did not show any sudden loss of drain currents, the degradations in the characteristics were negligible.

  10. The effect of small radiation doses on the rat spinal cord: the concept of partial tolerance

    International Nuclear Information System (INIS)

    Ang, K.K.; Van Der Kogel, A.J.; Van Der Schueren, E.

    1983-01-01

    To evaluate the tolerance of the rat spinal cord to small radiation doses per fraction, an increasing number of fractions is required for induction of paralysis. The assessment of doses of 1-2 Gy, as used in the clinic, would require that over 100 fractions be given. The validity of replacing part of a fractionated irradiation of the spinal cord by a single large dose has been tested. Fractionated irradiation doses with 18 MeV X rays were followed by a ''top-up'' dose of 15 Gy as a single treatment. This is the fraction size of a treatment with two irradiation doses leading to paralysis in 50% of the animals (ED 50). Fractionated treatments were carried out with 2, 5, 10 and 20 fractions followed by the top-up dose of 15 Gy. the isoeffect curve, as a function of the number of fractions, has the same slope as experiments performed without top-up dose. The results show that the quality and quantity of cellular repair is not modified when part of a multifractionated exposure is replaced by a larger top-dose. An important consequence of this finding is, that in treatments with unequal fraction sizes, the partial tolerances can simply be added. Since a top-up dose can replace a sizable number of irradiation treatments, its application will allow investigations of the extent of sublethal damage repair for fraction sizes as low as 1 Gy

  11. Theoretical investigation on radiation tolerance of {{\\boldsymbol{M}}}_{{\\boldsymbol{n}}+1}{{\\boldsymbol{AX}}}_{{\\boldsymbol{n}}} phases

    Science.gov (United States)

    Yin, Ke-Di; Zhang, Xi-Tong; Huang, Qing; Xue, Jian-Ming

    2017-06-01

    Ternary {M}n+1{{AX}}n phases with layered hexagonal structures, as candidate materials used for next-generation nuclear reactors, have shown great potential in tolerating radiation damage due to their unique combination of ceramic and metallic properties. However, {M}n+1{{AX}}n materials behave differently in amorphization when exposed to energetic neutron and ion irradiations in experiment. We first analyze the irradiation tolerances of different {M}n+1{{AX}}n (MAX) phases in terms of electronic structure, including the density of states (DOS) and charge density map. Then a new method based on the Bader analysis with the first-principle calculation is used to estimate the stabilities of MAX phases under irradiation. Our calculations show that the substitution of Cr/V/Ta/Nb by Ti and Si/Ge/Ga by Al can increase the ionicities of the bonds, thus strengthening the radiation tolerance. It is also shown that there is no obvious difference in radiation tolerance between {M}n+1A{{{C}}}n and {M}n+1A{{{N}}}n due to the similar charge transfer values of C and N atoms. In addition, the improved radiation tolerance from Ti3AlC2 to Ti2AlC (Ti3AlC2 and Ti2AlC have the same chemical elements), can be understood in terms of the increased Al/TiC layer ratio. Criteria based on the quantified charge transfer can be further used to explore other {M}n+1{{AX}}n phases with respect to their radiation tolerance, playing a critical role in choosing appropriate MAX phases before they are subjected to irradiation in experimental test for future nuclear reactors. Project supported by the National Natural Science Foundation of China (Grant Nos. 91226202 and 91426304).

  12. Study in radiation tolerance of damaged liver induced by dimethylaminoazobenzene. Histological study using Wistar rats

    International Nuclear Information System (INIS)

    Izumiyama, Kazutaka; Kodama, Akihisa; Kono, Michio

    1997-01-01

    We studied to determine the tolerable dose of radiation in damaged liver using Wistar male rats aged 4 weeks. A damaged liver group fed on low-protein animal chow containing 0.07% dimethylaminoazobenzene (DAB) ad libitum. Rats feeding on the chow without DAB served as the normal liver group. In both groups, two rats each underwent irradiation of the right half of the liver with doses of 5 Gy, 10 Gy, 15 Gy, or 20 Gy using a 15 MeV electron beam. The animals were sacrificed 2 or 4 weeks after irradiation, and the irradiated and non-irradiated parts of the liver were compared histologically with respect to hepatocellular necrosis, the extent of degeneration, and the degree of inflammatory cell infiltration, as well as the degree of inflammatory cell infiltration and fibrosis in Glisson's capsule. Secondly, in the normal liver group, 6 rats were irradiated with dose of 20 Gy, and in the damaged liver group, 6 rats each were irradiated with doses of 10 Gy, 12 Gy, 15 Gy or 20 Gy, and the same study was performed. In the normal liver group, no histological differences were seen between the irradiated and non-irradiated parts of the liver even when irradiated with 20 Gy dose. In the damaged liver group, there were no differences between the irradiated and non-irradiated parts of the liver in animals given 15 Gy or 10 Gy. In the 12 Gy group, however, one out of three rats each showed more severe changes in the irradiated part at 2 and 4 weeks after irradiation. One out of six rats in the 15 Gy group and four out of six rats in the 20 Gy group died in the first week after irradiation. In the damaged liver group, a single irradiation of up to 10 Gy delivered to one half of the liver was tolerable. At doses of 12 Gy or higher, however, irreversible changes occurred in some animals, and deaths occurred at 15 Gy or 20 Gy. Since even 20 Gy was tolerated in the normal liver group, damaged liver showed a lower tolerance than normal liver. (author)

  13. Radiation Tolerance of Controlled Fusion Welds in High Temperature Oxidation Resistant FeCrAl Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    High temperature oxidation resistant iron-chromium-aluminum (FeCrAl) alloys are candidate alloys for nuclear applications due to their exceptional performance during off-normal conditions such as a loss-of-coolant accident (LOCA) compared to currently deployed zirconium-based claddings [1]. A series of studies have been completed to determine the weldability of the FeCrAl alloy class and investigate the weldment performance in the as-received (non-irradiated) state [2,3]. These initial studies have shown the general effects of composition and microstructure on the weldability of FeCrAl alloys. Given this, limited details on the radiation tolerance of FeCrAl alloys and their weldments exist. Here, the highest priority candidate FeCrAl alloys and their weldments have been investigated after irradiation to enable a better understanding of FeCrAl alloy weldment performance within a high-intensity neutron field. The alloys examined include C35M (Fe-13%Cr-5% Al) and variants with aluminum (+2%) or titanium carbide (+1%) additions. Two different sub-sized tensile geometries, SS-J type and SS-2E (or SS-mini), were neutron irradiated in the High Flux Isotope Reactor to 1.8-1.9 displacements per atom (dpa) in the temperature range of 195°C to 559°C. Post irradiation examination of the candidate alloys was completed and included uniaxial tensile tests coupled with digital image correlation (DIC), scanning electron microscopy-electron back scattered diffraction analysis (SEM-EBSD), and SEM-based fractography. In addition to weldment testing, non-welded parent material was examined as a direct comparison between welded and non-welded specimen performance. Both welded and non-welded specimens showed a high degree of radiation-induced hardening near irradiation temperatures of 200°C, moderate radiation-induced hardening near temperatures of 360°C, and almost no radiation-induced hardening at elevated temperatures near 550°C. Additionally, low-temperature irradiations showed

  14. Normal tissue tolerance to external beam radiation therapy: Esophagus; Dose de tolerance a l'irradiation des tissus sains: l'oesophage

    Energy Technology Data Exchange (ETDEWEB)

    Bera, G.; Pointreau, Y. [Clinique d' oncologie-radiotherapie, centre Henry-S.-Kaplan, hopital Bretonneau, CHU de Tours, 37 - Tours (France); Denis, F.; Dupuis, O. [Centre Jean-Bernard, clinique Victor-Hugo, 72 - Le-Mans (France); Orain, I. [Service d' anatomie et cytologie pathologiques, hopital Trousseau, CHU de Tours, 37 - Tours (France); Crehange, G. [Departement de radiotherapie, centre Georges-Francois-Leclerc, 21 - Dijon (France)

    2010-07-15

    The esophagus is a musculo-membranous tube through which food passes from the pharynx to the stomach. Due to its anatomical location, it can be exposed to ionizing radiation in many external radiotherapy indications. Radiation-induced esophageal mucositis is clinically revealed by dysphagia and odynophagia, and usually begins 3 to 4 weeks after the start of radiation treatment. With the rise of multimodality treatments (e.g., concurrent chemoradiotherapy, dose escalation and accelerated fractionation schemes), esophageal toxicity has become a significant dose-limiting issue. Understanding the predictive factors of esophageal injury may improve the optimal delivery of treatment plans. It may help to minimize the risks, hence increasing the therapeutic ratio. Based on a large literature review, our study describes both early and late radiation-induced esophageal injuries and highlights some of the predictive factors for cervical and thoracic esophagus toxicity. These clinical and dosimetric parameters are numerous but none is consensual. The large number of dosimetric parameters strengthens the need of an overall analysis of the dose/volume histograms. The data provided is insufficient to recommend their routine use to prevent radiation-induced esophagitis. Defining guidelines for the tolerance of the esophagus to ionizing radiation remains essential for a safe and efficient treatment. (authors)

  15. A radiation tolerance study of the ALICE TPC Readout Control Unit 2

    CERN Document Server

    Zhao, Chengxin; Balk, Helge; Alme, Johan

    2017-11-17

    ALICE is a general-purpose detector that is designed to study the physics of quark-gluon plasma. The Time Projection Chamber (TPC) is one of the major detectors of ALICE. The TPC electronics consists of 4356 Front-end cards (FECs), which are controlled by 216 Readout Control Units (RCU). Each RCU connects to between 18 and 25 FECs using a multi-drop bus. In LHC Run1, the Readout Control Unit 1 (RCU1) performed even better than specification. However, in Run2 the energy of colliding beams is increased from 8 TeV to 14 TeV (maximum value) and higher luminosity, which leads to larger event size and higher radiation load on the electronics. As a solution, the Readout Control Unit 2 (RCU2) is designed to provide faster readout speed and improved radiation tolerance with respect to the RCU1. The RCU2 is conceptually similar to the RCU1 and it reuses the existing infrastructure and readout architecture of the TPC electronics. However, the multi-drop bus is split into four branches from the two branches and the bandw...

  16. LEVEL-1 DATA DRIVER CARD - A high bandwidth radiation tolerant aggregator board for detectors

    CERN Document Server

    Gkountoumis, Panagiotis; The ATLAS collaboration

    2018-01-01

    The Level-1 Data Driver Card (L1DDC) was designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The detectors located at the muon Small Wheels will be replaced by a set of precision tracking and trigger detectors, the resistive Micromegas (MM) and the small-strip Thin Gap Chambers (sTGC). After the upgrade, the number of interactions per bunch-crossing will be increased up to 140, resulting in a dramatically large amount of produced data. The high number of electronic channels (about two million for the MM and about 300k for the sTGC) along with a harsh environment (radiation dose up to 1700Gy (inner radius) and a magnetic field up to 0:4T in the end cap region) led to the development of new radiation tolerant electronics and a scalable readout scheme able to handle the new data rates. In addition, correction mechanisms for Single Event Upsets (SEU) and communication errors must be implemented to assure the integrity of the transmitted data. The L1DDC i...

  17. Evaluation of radiation tolerance of TMR designs in SRAM-based FPGA.

    CERN Document Server

    Shibin, Konstantin

    2016-01-01

    During the Summer Student program in CERN I was working in the CMS Muon Drift Tube group, building a setup for evaluating the radiation tolerance of the drift tube signal encoding hardware (Time-to-Digital Converter, TDC) implemented in SRAM-based FPGA using Triple Modular Redundancy (TMR). While commercially available SRAM-based FPGAs have more computational power, are more advanced in general than flash-based FPGAs and are the most suitable technology for implementing the TDC logic (also taking into account the performance requirements), in the context of operation inside an environment with high levels of ionizing radiation (such as inside CMS DT detector) they are more susceptible to configuration memory bit flips – Single Event Upsets (SEUs) - due to lower required energy for a memory bit being flipped. The effect of a SEU inside the configuration memory might change the functionality of the underlying building blocks of FPGA and if the respective blocks were involved in implementing the desired custom...

  18. Development of radiation-tolerant components for the quench detection system at the CERN Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Bitterling, Oliver

    2017-04-03

    This works describes the results of a three year project to improve the radiation tolerance of the Quench Protection System of the CERN Large Hadron Collider. Radiation-induced premature beam aborts have been a limiting factor for accelerator availability in the recent years. Furthermore, the future upgrade of the Large Hadron Collider to its High Luminosity phase will further increase the radiation load and has higher requirements for the overall machine availability. Therefore equipment groups like the Quench protection groups have used the last years to redesign many of their systems to fulfill those requirements. In support of the development of radiation-tolerant systems, several proton beam irradiation campaigns were conducted to determine the inherent radiation tolerance of a selection of varied electronic components. Using components from this selection a new Quench Protection System for the 600 A corrector magnets was developed. The radiation tolerance of this system was further improved by developing a filter and error correction system for all discovered failure modes. Furthermore, compliance of the new system with the specification was shown by simulating the behavior of the system using data taken from the irradiation campaigns. The resulting system is operational since the beginning of 2016 and has in the first 9 months of operation not shown a single radiation-induced failure. Using results from simulations and irradiation campaigns the predicted failure cross section for the full new 600 A Quench Protection System is 4.358±0.564.10{sup -10} cm{sup 2} which is one order of magnitude lower than the target set during the development of this system.

  19. Development of radiation-tolerant components for the quench detection system at the CERN Large Hadron Collider

    International Nuclear Information System (INIS)

    Bitterling, Oliver

    2017-01-01

    This works describes the results of a three year project to improve the radiation tolerance of the Quench Protection System of the CERN Large Hadron Collider. Radiation-induced premature beam aborts have been a limiting factor for accelerator availability in the recent years. Furthermore, the future upgrade of the Large Hadron Collider to its High Luminosity phase will further increase the radiation load and has higher requirements for the overall machine availability. Therefore equipment groups like the Quench protection groups have used the last years to redesign many of their systems to fulfill those requirements. In support of the development of radiation-tolerant systems, several proton beam irradiation campaigns were conducted to determine the inherent radiation tolerance of a selection of varied electronic components. Using components from this selection a new Quench Protection System for the 600 A corrector magnets was developed. The radiation tolerance of this system was further improved by developing a filter and error correction system for all discovered failure modes. Furthermore, compliance of the new system with the specification was shown by simulating the behavior of the system using data taken from the irradiation campaigns. The resulting system is operational since the beginning of 2016 and has in the first 9 months of operation not shown a single radiation-induced failure. Using results from simulations and irradiation campaigns the predicted failure cross section for the full new 600 A Quench Protection System is 4.358±0.564.10 -10 cm 2 which is one order of magnitude lower than the target set during the development of this system.

  20. An iterative method applied to optimize the design of PIN photodiodes for enhanced radiation tolerance and maximum light response

    International Nuclear Information System (INIS)

    Cedola, A.P.; Cappelletti, M.A.; Casas, G.; Peltzer y Blanca, E.L.

    2011-01-01

    An iterative method based on numerical simulations was developed to enhance the proton radiation tolerance and the responsivity of Si PIN photodiodes. The method allows to calculate the optimal values of the intrinsic layer thickness and the incident light wavelength, in function of the light intensity and the maximum proton fluence to be supported by the device. These results minimize the effects of radiation on the total reverse current of the photodiode and maximize its response to light. The implementation of the method is useful in the design of devices whose operation point should not suffer variations due to radiation.

  1. An FMEA evaluation of intensity modulated radiation therapy dose delivery failures at tolerance criteria levels.

    Science.gov (United States)

    Faught, Jacqueline Tonigan; Balter, Peter A; Johnson, Jennifer L; Kry, Stephen F; Court, Laurence E; Stingo, Francesco C; Followill, David S

    2017-11-01

    The objective of this work was to assess both the perception of failure modes in Intensity Modulated Radiation Therapy (IMRT) when the linac is operated at the edge of tolerances given in AAPM TG-40 (Kutcher et al.) and TG-142 (Klein et al.) as well as the application of FMEA to this specific section of the IMRT process. An online survey was distributed to approximately 2000 physicists worldwide that participate in quality services provided by the Imaging and Radiation Oncology Core - Houston (IROC-H). The survey briefly described eleven different failure modes covered by basic quality assurance in step-and-shoot IMRT at or near TG-40 (Kutcher et al.) and TG-142 (Klein et al.) tolerance criteria levels. Respondents were asked to estimate the worst case scenario percent dose error that could be caused by each of these failure modes in a head and neck patient as well as the FMEA scores: Occurrence, Detectability, and Severity. Risk probability number (RPN) scores were calculated as the product of these scores. Demographic data were also collected. A total of 181 individual and three group responses were submitted. 84% were from North America. Most (76%) individual respondents performed at least 80% clinical work and 92% were nationally certified. Respondent medical physics experience ranged from 2.5 to 45 yr (average 18 yr). A total of 52% of individual respondents were at least somewhat familiar with FMEA, while 17% were not familiar. Several IMRT techniques, treatment planning systems, and linear accelerator manufacturers were represented. All failure modes received widely varying scores ranging from 1 to 10 for occurrence, at least 1-9 for detectability, and at least 1-7 for severity. Ranking failure modes by RPN scores also resulted in large variability, with each failure mode being ranked both most risky (1st) and least risky (11th) by different respondents. On average MLC modeling had the highest RPN scores. Individual estimated percent dose errors and severity

  2. Normal tissue tolerance to external beam radiation therapy: Thyroid; Dose de tolerance des tissus sains: la thyroide

    Energy Technology Data Exchange (ETDEWEB)

    Berges, O.; Giraud, P. [Service d' oncologie-radiotherapie, hopital europeen Georges-Pompidou, universite Paris Descartes, 75 - Paris (France); Belkacemi, Y. [Service d' oncologie-radiotherapie, CHU Henri-Mondor, universite Paris 12, 94 - Creteil (France)

    2010-07-15

    The thyroid is the most developed endocrine gland of the body. Due to its anatomical location, it may be exposed to ionizing radiation in external radiotherapy involving head and neck. This review aims to describe the thyroid radiation disorders, probably under-reported in the literature, their risk factors and follow-up procedures. The functional changes after external beam radiation consists mainly of late effects occurring beyond 6 months, and are represented by the clinical and subclinical hypothyroidism. Its incidence is approximately 20 to 30% and it can occur after more than 25 years after radiation exposure. Hyperthyroidism and auto-immune manifestations have been described in a lesser proportion. The morphological changes consist of benign lesions, primarily adenomas, and malignant lesions, the most feared and which incidence is 0.35%. The onset of hypothyroidism depends of the total dose delivered to the gland, and the irradiated. Modern techniques of conformal radiotherapy with modulated intensity could improve the preservation of the thyroid, at the expense of the increase in low doses and the theoretical risk of secondary cancers. (authors)

  3. Level-1 Data Driver Card - A high bandwidth radiation tolerant aggregator board for detectors

    CERN Document Server

    Gkountoumis, Panagiotis; The ATLAS collaboration

    2017-01-01

    The Level-1 Data Driver Card (L1DDC) was designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The L1DDC is a high speed aggregator board capable of communicating with multiple front-end electronic boards. It collects the Level-1 data along with monitoring data and transmits them to a network interface through bidirectional and/or unidirectional fiber links at 4.8 Gbps each. In addition, the L1DDC board distributes trigger, time and configuration data coming from the network interface to the front-end boards. The L1DDC is fully compatible with the Phase II upgrade where the trigger rate is expected to reach the 1 MHz. Three different types of L1DDC boards will be fabricated handling up to 10.080 Gbps of user data. It consist of custom made radiation tolerant ASICs: the GigaBit Transceiver (GBTx), the FEAST DC-DC converter, the Slow Control Adapter (SCA), and the Versatile Tranceivers (VTRX) and transmitters (VTTX). The overall scheme of the data acquis...

  4. A large dynamic range radiation-tolerant analog memory in a quarter- micron CMOS technology

    CERN Document Server

    Anelli, G; Rivetti, A

    2001-01-01

    An analog memory prototype containing 8*128 cells has been designed in a commercial quarter-micron CMOS process. The aim of this work is to investigate the possibility of designing large dynamic range mixed-mode switched capacitor circuits for high-energy physics (HEP) applications in deep submicron CMOS technologies. Special layout techniques have been used to make the circuit radiation tolerant. The memory cells employ gate-oxide capacitors for storage, permitting a very high density. A voltage write-voltage read architecture has been chosen to minimize the sensitivity to absolute capacitor values. The measured input voltage range is 2.3 V (the power supply voltage V/sub DD/ is equal to 2.5 V), with a linearity of almost 8 bits over 2 V. The dynamic range is more than 11 bits. The pedestal variation is +or-0.5 mV peak-to-peak. The noise measured, which is dominated by the noise of the measurement setup, is around 0.8 mV rms. The characteristics of the memory have been measured before irradiation and after 1...

  5. A large dynamic range radiation tolerant analog memory in a quarter micron CMOS technology

    CERN Document Server

    Anelli, G; Rivetti, A

    2000-01-01

    A 8*128 cell analog memory prototype has been designed in a commercial 0.25 jam CMOS process. The aim of this work was to investigate the possibility of designing large dynamic range mixed- mode switched capacitor circuits for High-Energy Physics (HEP) applications in deep submicron CMOS technologies. Special layout techniques have been used to make the circuit radiation tolerant left bracket 1 right bracket . The memory cells employ gate-oxide capacitors for storage, allowing for a very high density. A voltage write - voltage read architecture has been chosen to minimize the sensitivity to absolute capacitor values. The measured input voltage range is 2.3 V (V//D//D = 2.5 V), with a linearity of at least 7.5 bits over 2 V. The dynamic range is more than 11 bits. The pedestal variation is plus or minus 0.5 mV peak-to-peak. The noise measured, which is dominated by the noise of the measurement setup, is around 0.8 mV rms. The characteristics of the memory have been measured before irradiation and after lOMrd (...

  6. Radiation-tolerant, red-sensitive CCDs for dark energy investigations

    International Nuclear Information System (INIS)

    Roe, N.A.; Bebek, C.J.; Dawson, K.S.; Emes, J.H.; Fabricius, M.H.; Fairfield, J.A.; Groom, D.E.; Holland, S.E.; Karcher, A.; Kolbe, W.F.; Palaio, N.P.; Wang, G.

    2007-01-01

    We describe the development of thick (200-300 μm), fully depleted p-channel, charge-coupled devices (CCDs). The advantages of these CCDs relative to conventional thin, n-channel CCDs include: high quantum efficiency over a wide range of wavelengths, extending into the near-infrared; negligible fringing at long (∼900-1000 nm) wavelengths; improved radiation tolerance; and a small point-spread function controlled through the application of the bias voltage. These visible-to-near-infrared light detectors are good candidates for the next generation of large focal-plane mosaics under development for dark energy measurements. The Dark Energy Survey has selected these CCDs for the focal plane of a new camera being designed for the Blanco 4 m telescope at CTIO in Chile. They also meet all the requirements for the visible-light detectors for the SuperNova/Acceleration Probe, a satellite-based experiment designed to make precision measurements of dark energy

  7. The GBT-SCA, a radiation tolerant ASIC for detector control applications in SLHC experiments

    CERN Document Server

    Gabrielli, A; Kloukinas, K; Marchioro, A; Moreira, P; Ranieri, A; De Robertis, D

    2009-01-01

    This work describes the architecture of the GigaBit Transceiver – Slow Control Adapter (GBT–SCA) ASIC suitable for the control and monitoring applications of the embedded front-end electronics in the future SLHC experiments. The GBT–SCA is part the GBT chipset currently under development for the SLHC detector upgrades. It is designed for radiation tolerance and it will be fabricated in a commercial 130 nm CMOS technology. The paper discusses the GBT-SCA architecture, the data transfer protocol, the ASIC interfaces, and its integration with the GBT optical link. The GBT–SCA is one the components of the GBT system chipset. It is proposed for the future SLHC experiments and is designed to be configurable matching different front-end system requirements. The GBT-SCA is intended for the slow control and monitoring of the embedded front end electronics and implements a point-to-multi point connection between one GBT optical link ASIC and several front end ASICs. The GBT-SCA connects to a dedicated electrica...

  8. Normal tissue tolerance to external beam radiation therapy: Skin; Dose de tolerance des tissus sains: la peau et les phaneres

    Energy Technology Data Exchange (ETDEWEB)

    Ginot, A.; Doyen, J.; Hannoun-Levi, J.M.; Courdi, A. [Service d' oncologie-radiotherapie, centre Antoine-Lacassagne, 06 - Nice (France)

    2010-07-15

    Acute skin toxicity is frequent during radiation therapy and can lead to temporary arrest of the treatment. Chronic toxicity can occur and conduct to cosmetic problems. Alopecia is the most frequent toxicity concerning hair and is most of the time reversible. Several factors linked to patients influence skin toxicity, such as under-nutrition, old age, obesity, smoking, skin diseases, autoimmune diseases, failure of DNA reparation. Skin, hair and nail toxicities depend also on radiation schedule. Acute toxicity is greater when dose per fraction increases. Chronic and acute toxicities are more often when total dose increases. Under 45 Gy, the risk of severe skin toxicity is low, and begins above 50 Gy. Skin toxicity depends also on the duration of radiotherapy and split course schedules are associated with less toxicities. Irradiation surface seems to influence skin toxicity but interaction is more complex. Reirradiation is often feasible in case of cancer recurrence but with a risk of grade 3-4 toxicity above all in head and neck cancer. The benefit/risk ratio has to be always precisely evaluated. Permanent alopecia is correlated with the follicle dose. Modern techniques of radiation therapy allow to spare skin. (authors)

  9. Normal tissue tolerance to external beam radiation therapy: Cardiac structures; Dose de tolerance des tissus sains: le coeur

    Energy Technology Data Exchange (ETDEWEB)

    Doyen, J. [Service d' oncologie-radiotherapie, centre Antoine-Lacassagne, 06 - Nice (France); Giraud, P. [Universite Rene-Descartes Paris 5, 75 - Paris (France); Service d' oncologie-radiotherapie, hopital europeen Georges-Pompidou, 75 - Paris (France); Belkacemi, Y. [Faculte de medecine de Creteil, universite Paris 12, 94 - Creteil (France); Service d' oncologie-radiotherapie, CHU Henri-Mondor, 94 - Creteil (France)

    2010-07-15

    Radiation thoracic tumors may be associated with cardiac toxicity because of the central position of the heart in the thorax. The present review aims to describe the cardiotoxicity during radiotherapy of different tumor sites most associated with this complication and the risk factors of cardiotoxicity during radiation therapy. Medline literature searches were performed using the following cardiac - heart - radiotherapy - toxicity - cardiotoxicity - breast cancer - lymphoma. Cardiac toxicity after breast cancer and mediastinal lymphoma is the most reported radiation-induced complication. The most frequent clinical complications are pericarditis, congestive heart failure, and heart infarction. These events are mostly asymptomatic. Thus clinicians have to give particular attention to these complications. Anthracycline treatment is a major risk factor for additional cardiotoxicity during radiotherapy with a synergistic effect. Correction of cardiovascular risk is an important point of the prevention of heart complications. Total dose delivered to the planned target volume (PTV), the dose per fraction and the irradiated volume were correlated to the risk of cardiotoxicity. Volume of heart receiving 35 Gy must be inferior to 30% and dose per fraction should not exceed 2 Gy when dose of prescription exceeds 30 Gy. Maximum heart distance (maximal thickness of heart irradiated) must be less than 1 cm during irradiation of breast cancer. Modern irradiation techniques seem to be associated with a limited risk of heart complication. The use of anthracycline, other cardio-toxic chemotherapies and targeted therapies should incite for great caution by performing a careful treatment planning and optimisation. (authors)

  10. A > 4 MGy radiation tolerant 8 THzOhm transimpedance amplifier with 50 dB dynamic range

    International Nuclear Information System (INIS)

    Verbeeck, J; Steyaert, M; Leroux, P

    2013-01-01

    A 130 nm Transimpedance Amplifier has been developed with a 255 MHz bandwidth, 90 dBΩ transimpedance gain and a dynamic input range of 1:325 or 50 dB for a photo-diode capacitance of 0.75 pF. The equivalent integrated input noise is 160 nA - 25°C. The gain of the voltage amplifier, used in the transimpedance amplifier (TIA), degrades less than 3% over a temperature range from -40 °C up to 125 °C. The TIA and attenuator exhibit a radiation tolerance larger than 4 MGy, as evidenced by radiation assessment.

  11. Effect of gamma radiation on different explants of sweet potato (Ipomoea batatas L. (Lam)) to induce NaCl tolerance

    International Nuclear Information System (INIS)

    Gutierrez-Rosati, A.

    1997-01-01

    Clonal lines tolerant to NaCl were obtained by combining in vitro culture and gamma radiation in two Peruvian varieties 'Amarillo de Quillabamba' and 'Nemanete'. The most suitable explants were pedicel sections and leaf blades. Embryogenic callus was induced on basal MS basal medium containing 0.5 ppm 2,4-D. The embryogenic calli were irradiated with 5 Gy from a 137 Cs source. Several putative mutants appeared to be stable. (author). 9 refs, 3 tabs

  12. Effect of gamma radiation on different explants of sweet potato (Ipomoea batatas L. (Lam)) to induce NaCl tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez-Rosati, A [Biology Dept., National Agriculture Univ., La Molina, Lima (Peru)

    1997-07-01

    Clonal lines tolerant to NaCl were obtained by combining in vitro culture and gamma radiation in two Peruvian varieties `Amarillo de Quillabamba` and `Nemanete`. The most suitable explants were pedicel sections and leaf blades. Embryogenic callus was induced on basal MS basal medium containing 0.5 ppm 2,4-D. The embryogenic calli were irradiated with 5 Gy from a {sup 137}Cs source. Several putative mutants appeared to be stable. (author). 9 refs, 3 tabs.

  13. Selection and characterizations of radiation-induced salinity-tolerant lines in rice

    International Nuclear Information System (INIS)

    Lee, I.S.; Kim, D.S.; Lee, S.J.; Song, H.S.; Lim, Y.P.; Lee, Y.I.

    2003-01-01

    NaCl tolerant cell lines were selected from irradiated callus, which were generated from seed cultures. M 1 -regenerates were obtained from the salt-tolerant callus cultured on the auxin-free medium for 30 days. Some regenerants were more tolerant than the parent variety (Dongjinbyeo) on a medium containing 0.75 % NaCl. Seeds (M 3 5,000 lines) derived from M 2 lines were grown to the 3 leaf stage. M 3 lines were soaked with a 0.75 % salt solution for 3 weeks and 350 salt-tolerant genotypes were selected. Among the M 3 350 lines, forty tolerant lines were selected from a saline field (10~14 mS) near the sea coast. Of the forty lines, two lines (18-1 and 50-1) showed more improved plant height, panicle length, tillering number, spikelet number and yield than those of the original variety. Thirty primers were screened and two RAPD markers were identified, which appeared in both the salt-tolerant lines (18-1 and 50-1). From DNA-hybridization experiments, it appeared that the fragment arose from the middle-repetitive copy sequences. The transcript involved in the marker showed a higher expression in the salt-tolerant lines than the sensitive lines. The salt-tolerant lines would be useful as a resource for salt-tolerant breeding. (author)

  14. Tolerance of the canine bladder to intraoperative radiation therapy: an experimental study

    International Nuclear Information System (INIS)

    Kinsella, T.J.; Sindelar, W.F.; DeLuca, A.M.; Barnes, M.; Tochner, Z.; Mixon, A.; Glatstein, E.

    1988-01-01

    An experimental study of bladder tolerance to intraoperative radiotherapy (IORT) was designed using a large animal model (adult American Foxhounds, weight 25-30 kg) to access acute and late radiation effects. Dogs were subjected to laparotomy where the bladder was mobilized and IORT was delivered using a 5 cm circular cone through a cystotomy incision with 12 MeV electrons. The bladder trigone including both ureteral orifices and the proximal urethra was irradiated in groups of 3 dogs with doses of 0, 20, 25, 30, 35, and 40 Gy. Dogs were followed clinically with repeat urinalysis, intravenous pyelogram (IVP), and cystometrogram at 1 month and then Q6 months for up to 4 years. One dog from each dose group was sacrificed electively at 1 and 2 years, whereas the other dog is being followed clinically for a minimum of 4 years. Complete autopsies were performed with particular attention to genitourinary and pelvic structures. No clinically detectable acute toxicity resulted from IORT to the bladder. Three of 15 IORT dogs (1 each at 25, 35, and 40 Gy) showed obstruction of a ureteral orifice with 2 dogs dying of renal failure secondary to bilateral hydronephrosis within 1-2 years of treatment. The remaining 12 IORT dogs and 3 control dogs have normal repeat IVP's and renal function with up to 4 years of follow-up. Serial cystometry demonstrates no major loss of bladder contractility or volume. At autopsy, histological changes of mucosal thinning and telangiectasia with submucosal fibrosis were confined to the IORT field and appeared dose-related. However, the bladder epithelium remained intact at all doses. The ureterovesical junction in animals receiving 20 Gy showed mild fibrosis of the lamina propria and moderate chronic inflammation. Above 20 Gy, these histological changes at the U-V junction were more pronounced with gross stenosis in 3 animals as predicted by the IVP

  15. Normal tissue tolerance to external beam radiation therapy: Peripheral nerves; Dose de tolerance a l'irradiation des tissus sains: les nerfs peripheriques

    Energy Technology Data Exchange (ETDEWEB)

    Henriques de Figueiredo, B.; Dejean, C.; Sargos, P.; Kantor, G. [Departement de radiotherapie, institut Bergonie, centre regional de lutte contre le cancer, 33 - Bordeaux (France); Huchet, A.; Mamou, N. [Service d' oncologie medicale et de radiotherapie, CHU Saint-Andre, 33 - Bordeaux (France); Loiseau, H. [Service de neurochirurgie, CHU Pellegrin, 33 - Bordeaux (France)

    2010-07-15

    Plexopathies and peripheral neuropathies appear progressively and with several years delay after radiotherapy. These lesions are observed principally after three clinical situations: supraclavicular and axillar irradiations for breast cancer, pelvic irradiations for various pathologies and limb irradiations for soft tissue sarcomas. Peripheral nerves and plexus (brachial and lumbosacral) are described as serial structures and are supposed to receive less than a given maximum dose linked to the occurrence of late injury. Literature data, mostly ancient, define the maximum tolerable dose to a threshold of 60 Gy and highlight also a great influence of fractionation and high fraction doses. For peripheral nerves, most frequent late effects are pain with significant differences of occurrence between 50 and 60 Gy. At last, associated pathologies (diabetes, vascular pathology, neuropathy) and associated treatments have probably to be taken into account as additional factors, which may increase the risk of these late radiation complications. (authors)

  16. Mechanism of radiation tolerance in higher plants. Radiation damage of DNA in cultured tobacco BY-2 cells and implication from its repair process

    International Nuclear Information System (INIS)

    Yokota, Yuichiro; Narumi, Issay; Funayama, Tomoo; Kobayashi, Yasuhiko; Tanaka, Jun; Inoue, Masayoshi

    2007-01-01

    This paper describes the mechanism of radiation tolerance at the cellular level in higher plants, of which fundamental study basis is rather poor, in cultured cells in the title (BY-2 cells, Nicotiana tabacum L., allotetraploid). When compared with LD 50 of radiation in higher animals (2.4-8.6 Gy), higher plants are generally tolerant to radiation (known LD 50 , >360-2000 Gy). Authors have made unicellular BY-2 cells (protoplasts) by enzyme treatment to see their colony forming ability (CFA) and have found those cells are also resistant to radiation: D 10 (10% CFA dose) (Gy) is found to be 8.2-47.2 by radiation with various linear energy transfer (LET)s like gamma ray and heavy ion beams, in contrast to human D 10 (1.17-8.12, by X-ray and carbon beam). Double strand break (DSB) of DNA by radiation per one BY-2 cell initially occurs 7-10 times more frequently than mammalian cells (CHO-K1). However, DSB repair in BY-2 cells is found only as efficient as in mammalian cells: a slow repair relative to DSB number. Checkpoint mechanism of DNA damage is found poorly working in BY-cells, which results in frequent chromosome aberration like micronucleus. Authors consider that, for an herbaceous plant, to precede the cell cycle rather than to recover from the genomic instability can be profitable for growing more rapidly to have more sunlight energy than other individuals. Improvement of plants by gene technological approach with such a mean as mutation by radiation is conceivably important from aspects of food supply and of ecological environment. (R.T.)

  17. Implications of the quadratic cell survival curve and human skin radiation ''tolerance doses'' on fractionation and superfractionation dose selection

    International Nuclear Information System (INIS)

    Douglas, B.G.

    1982-01-01

    An analysis of early published multifraction orthovoltage human acute skin irradiation tolerance isoeffect doses is presented. It indicates that human acute skin radiation reactions may result from the repetition, with each dose fraction, of a cell survival curve of the form: S = e/sup -(αD + βD 2 )/). The analysis also shows no need for an independent proliferation related time factor for skin, for daily treatments of six weeks or less in duration. The value obtained for the constant β/α for orthovoltage irradiation from these data is 2.9 x 10 -3 rad -1 for the cell line determining acute skin tolerance. A radiation isoeffect relationship, based on the quadratic cell survival curve, is introduced for human skin. This relationship has some advantages over the nominal standard dose (NSD). First, its use is not restricted to tolerance level reactions. Second, a modification of the relationship, which is also introduced, may be employed in the selection of doses per treatment when irradiation dose fractions are administered at short intervals where repair of sublethal injury is incomplete

  18. The study of the extreme radiation tolerance mechanisms of the bacterium Deinococcus deserti by a functional genomics approach

    International Nuclear Information System (INIS)

    Dulermo, R.

    2009-12-01

    The genome of Deinococcus deserti, a highly radiation-tolerant bacterium, was analyzed and compared to those of D. radiodurans and D. geothermalis. About 230 proteins are specifically conserved in these 3 species, including IrrE, a regulator protein essential for radio tolerance. D.deserti has several supplementary DNA repair genes, like imuY and dnaE2 (trans-lesion DNA polymerases). Moreover, D. deserti has 3 recA that code for 2 different RecA proteins (RecAC et RecAP). To study these genes, genetic tools were developed for D. deserti. Different results suggest that IrrE, required for the induction of several genes after irradiation, has peptidase activity. The 2 RecA proteins are functional for DNA repair. D. deserti is mutable by UV, which requires ImuY, DnaE2 and RecAC, but not RecAP. (author)

  19. Design of a MGy radiation tolerant resolver-to-digital convertor IC for remotely operated maintenance in harsh environments

    Energy Technology Data Exchange (ETDEWEB)

    Leroux, Paul, E-mail: paul.leroux@kuleuven.be [KU Leuven, Dept. of Electrical Engineering (ESAT), AdvISe, Kleinhoefstraat 4, 2440 Geel (Belgium); Van Koeckhoven, Wesley; Verbeeck, Jens [KU Leuven, Dept. of Electrical Engineering (ESAT), AdvISe, Kleinhoefstraat 4, 2440 Geel (Belgium); Van Uffelen, Marco; Esqué, Salvador; Ranz, Roberto; Damiani, Carlo [Fusion for Energy, Torres Diagonal Litoral B3, Josep Pla 2, 08019 Barcelona (Spain); Hamilton, David [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul-lez-Durance (France)

    2014-10-15

    During future ITER maintenance operations, sensors and their embarked electronics will be exposed to a hostile and radioactive environment. This paper presents the design of a MGy radiation tolerant 16 bit resolver-to-digital converter (RDC) in 130 nm CMOS technology. The RDC features a Type II digital tracking loop, able to track resolvers with speeds up to 300 rps, and excitation frequencies up to 4 kHz. The RDC uses two integrated ΔΣ-analog-to-digital converters (ADCs) to digitize the resolver outputs. The 16 bit, 10 kHz ADCs utilize a correlated double sampling technique to remove radiation induced offset and 1/f-noise. The front-end features a static angular resolution of 16 bits (4.2 arcsec{sub rms}) and a resolution of 10 bits (6 arcmin{sub rms}) at a rotor speed of 100 rps. The circuit has a simulated radiation tolerance exceeding 1 MGy. It has the ability to operate under temperatures up to 125 °C, and to allow multiplexing with signals from other conventional sensors for compact, robust read-out architectures.

  20. Radiation response of the rat cervical spinal cord after irradiation at different ages: Tolerance, latency and pathology

    International Nuclear Information System (INIS)

    Ruifrok, A.C.C.; Van Der Kogel, A.J.; Stephens, L.C.

    1994-01-01

    Investigation of the age dependent single-dose radiation tolerance, latency to radiation myelopathy, and the histopathological changes after irradiation of the rat cervical spinal cord is presented. Rats were irradiated with graded single doses of 4 MV photons to the cervical spinal cord. When the rats showed definite signs of paresis of the forelegs, they were killed and processed for histological examination. The radiation dose resulting in paresis due to white matter damage in 50% of the animals (ED 50 ) after single dose irradiation was about 21.5 Gy at all ages ≥ 2 weeks. Only the Ed 50 at 1 week was significantly lower. The latency to the development of paresis clearly changed with the age at irradiation, from about 2 weeks after irradiation at 1 week to 6-8 months after irradiation at age ≥ 8 weeks. The white matter damage was similar in all symptomatic animals studied. The most prominent were areas with diffuse demyelination and swollen axons, often with focal necrosis, accompanied by glial reaction. This was observed in all symptomatic animals, irrespective of the age at irradiation. Expression of vascular damage appeared to depend on the age at irradiation. Although the latency to myelopathy is clearly age dependent, single dose tolerance is not age dependent at age ≥ 2 weeks in the rat cervical spinal cord. The white matter damage is similar in all symptomatic animals studied, but the vasculopathies appear to be influenced by the age at irradiation. It is concluded that white matter damage and vascular damage are separate phenomena contributing to the development of radiation myelopathy, expression of which may depend on the radiation dose applied and the age at irradiation. 28 refs., 5 figs., 3 tabs

  1. Tolerance and efficiency of radiation therapy treatment of the pelvic lymph nodes in patients with prostate cancer

    International Nuclear Information System (INIS)

    Hegemann, Nina-Sophie

    2013-01-01

    Tolerance and efficiency of radiation therapy treatment of the pelvic lymph nodes were assessed in 122 patients with prostate cancer. With no severe observed late toxicity the incidence for lymph node metastases was between 3,0% (primarily irradiated patients without lymph node or distant metastases) and 100% (primarily irradiated patients with lymph node and distant metastases) after 3 years. As it seems, the following subgroups might possibly profit the most from a dose escalation in the pelvic lymph nodes: primarily irradiated patients with positive lymph nodes and postoperatively irradiated patients in adjuvant/additive situation, with a biochemical or a local/lymph node recurrence.

  2. A proposed GaAs-based superlattice solar cell structure with high efficiency and high radiation tolerance

    Science.gov (United States)

    Goradia, Chandra; Clark, Ralph; Brinker, David

    1985-01-01

    A solar cell structure is proposed which uses a GaAs nipi doping superlattice. An important feature of this structure is that photogenerated minority carriers are very quickly collected in a time shorter than bulk lifetime in the fairly heavily doped n and p layers and these carriers are then transported parallel to the superlattice layers to selective ohmic contacts. Assuming that these already-separated carriers have very long recombination lifetimes, due to their being across an indirect bandgap in real space, it is argued that the proposed structure may exhibit superior radiation tolerance along with reasonably high beginning-of-life efficiency.

  3. Minimalist fault-tolerance techniques for mitigating single-event effects in non-radiation-hardened microcontrollers

    Science.gov (United States)

    Caldwell, Douglas Wyche

    Commercial microcontrollers--monolithic integrated circuits containing microprocessor, memory and various peripheral functions--such as are used in industrial, automotive and military applications, present spacecraft avionics system designers an appealing mix of higher performance and lower power together with faster system-development time and lower unit costs. However, these parts are not radiation-hardened for application in the space environment and Single-Event Effects (SEE) caused by high-energy, ionizing radiation present a significant challenge. Mitigating these effects with techniques which require minimal additional support logic, and thereby preserve the high functional density of these devices, can allow their benefits to be realized. This dissertation uses fault-tolerance to mitigate the transient errors and occasional latchups that non-hardened microcontrollers can experience in the space radiation environment. Space systems requirements and the historical use of fault-tolerant computers in spacecraft provide context. Space radiation and its effects in semiconductors define the fault environment. A reference architecture is presented which uses two or three microcontrollers with a combination of hardware and software voting techniques to mitigate SEE. A prototypical spacecraft function (an inertial measurement unit) is used to illustrate the techniques and to explore how real application requirements impact the fault-tolerance approach. Low-cost approaches which leverage features of existing commercial microcontrollers are analyzed. A high-speed serial bus is used for voting among redundant devices and a novel wire-OR output voting scheme exploits the bidirectional controls of I/O pins. A hardware testbed and prototype software were constructed to evaluate two- and three-processor configurations. Simulated Single-Event Upsets (SEUs) were injected at high rates and the response of the system monitored. The resulting statistics were used to evaluate

  4. Enhancement of radiation tolerance in GaAs/AlGaAs core–shell and InP nanowires

    Science.gov (United States)

    Li, Fajun; Xie, Xiaolong; Gao, Qian; Tan, Liying; Zhou, Yanping; Yang, Qingbo; Ma, Jing; Fu, Lan; Tan, Hark Hoe; Jagadish, Chennupati

    2018-06-01

    Radiation effects on semiconductor nanowires (NWs) have attracted the attention of the research community due to their potential applications in space and atomic fields. The effective implementation of NW devices in a radiation environment is a matter of concern. Here, the photoluminescence (PL) and time-resolved PL (TRPL) measurements were performed on both GaAs and InP NWs at room temperature before and after 1 MeV H+ irradiation with fluences ranging from 1 × 1011 to 5 × 1013 p cm‑2. It is found that the degradation of lifetime is size-dependent, and typically the minority carrier lifetime damage coefficient is closely correlated with the material and NW diameter. Compared to GaAs and InP bulk material counterparts, the lifetime damage coefficient of NWs decreases by a factor of about one order of magnitude. After irradiation, GaAs NWs with a smaller diameter show a much lower lifetime damage coefficient while InP NWs show an increase in carrier radiative lifetime. The increased size-dependent radiation hardness is mainly attributed to the defect sink effect and/or the improvement of a room temperature dynamic annealing mechanism of the NWs. The InP NWs also showed higher radiation tolerance than GaAs NWs.

  5. Enhancement of radiation tolerance in GaAs/AlGaAs core-shell and InP nanowires.

    Science.gov (United States)

    Li, Fajun; Xie, Xiaolong; Gao, Qian; Tan, Liying; Zhou, Yanping; Yang, Qingbo; Ma, Jing; Fu, Lan; Tan, Hark Hoe; Jagadish, Chennupati

    2018-06-01

    Radiation effects on semiconductor nanowires (NWs) have attracted the attention of the research community due to their potential applications in space and atomic fields. The effective implementation of NW devices in a radiation environment is a matter of concern. Here, the photoluminescence (PL) and time-resolved PL (TRPL) measurements were performed on both GaAs and InP NWs at room temperature before and after 1 MeV H + irradiation with fluences ranging from 1 × 10 11 to 5 × 10 13 p cm -2 . It is found that the degradation of lifetime is size-dependent, and typically the minority carrier lifetime damage coefficient is closely correlated with the material and NW diameter. Compared to GaAs and InP bulk material counterparts, the lifetime damage coefficient of NWs decreases by a factor of about one order of magnitude. After irradiation, GaAs NWs with a smaller diameter show a much lower lifetime damage coefficient while InP NWs show an increase in carrier radiative lifetime. The increased size-dependent radiation hardness is mainly attributed to the defect sink effect and/or the improvement of a room temperature dynamic annealing mechanism of the NWs. The InP NWs also showed higher radiation tolerance than GaAs NWs.

  6. Layout techniques to enhance the radiation tolerance of standard CMOS technologies demonstrated on a pixel detector readout chip

    CERN Document Server

    Snoeys, W; Burns, M; Campbell, M; Cantatore, E; Carrer, N; Casagrande, L; Cavagnoli, A; Dachs, C; Di Liberto, S; Formenti, F; Giraldo, A; Heijne, Erik H M; Jarron, Pierre; Letheren, M F; Marchioro, A; Martinengo, P; Meddi, F; Mikulec, B; Morando, M; Morel, M; Noah, E; Paccagnella, A; Ropotar, I; Saladino, S; Sansen, Willy; Santopietro, F; Scarlassara, F; Segato, G F; Signe, P M; Soramel, F; Vannucci, Luigi; Vleugels, K

    2000-01-01

    A new pixel readout prototype has been developed at CERN for high- energy physics applications. This full mixed mode circuit has been implemented in a commercial 0.5 mu m CMOS technology. Its radiation tolerance has been enhanced by designing all NMOS transistors in enclosed geometry and introducing guardrings wherever necessary. The technique is explained and its effectiveness demonstrated on various irradiation measurements on individual transistors and on the prototype. Circuit performance started to degrade only after a total dose of 600 krad-1.7 Mrad depending on the type of radiation. 10 keV X-rays, /sup 60/Co gamma-rays, 6.5 MeV protons, and minimum ionizing particles were used. Implications of this layout approach on the circuit design and perspectives for even deeper submicron technologies are discussed. (20 refs).

  7. Characterization of a wide dynamic-range, radiation-tolerant charge-digitizer asic for monitoring of Beam losses

    CERN Document Server

    Guido Venturini, G G; Dehning, B; Kayal, M

    2012-01-01

    An Application Specific Integrated Circuit (ASIC) has been designed and fabricated to provide a compact solution to digitize current signals from ionization chambers and diamond detectors, employed as beam loss monitors at CERN and several other high energy physics facilities. The circuit topology has been devised to accept positive and negative currents, to have a wide dynamic range (above 120 dB), withstand radiation levels over 10 Mrad and offer different modes of operation, covering a broad range of applications. Furthermore, an internal conversion reference is employed in the digitization, to provide an accurate absolute measurement. This paper discusses the detailed characterization of the first prototype: linearity, radiation tolerance and temperature dependence of the conversion, as well as implications and system-level considerations regarding its use for beam instrumentation applications in a high energy physics facility.

  8. Radiation tolerance qualification for maintenance tasks in the future fusion reactors: from fibre-optic components to robust data links

    International Nuclear Information System (INIS)

    Uffelen, M. van; Fernandez, A. Fernandez; Brichard, B.; Berghmans, F.; Decreton, M.

    2003-01-01

    The future International Thermonuclear Experimental Reactor (ITER) requires remote handling tools for its maintenance that will operate in a harsh environment. The numerous instrumentation cables for this maintenance equipment call for (de)multiplexing solutions, in order to reduce the umbilical size. Fibre-optic data links, using commercial-off-the-shelf (COTS) components, are seriously considered as a radiation tolerant solution, offering wavelength encoded multiplexing possibilities. However, an adapted modus operandi for a reliable assessment of this evolving technology is needed, to enable their long-term implementation in a radiation environment. In this paper, we present a methodology towards qualification methods for these instrumentation data links, and illustrate it with results obtained for different individual components. These results should enable the future design of robust architectures for communication links

  9. Radiation tolerance of the FOXFET biasing scheme for AC-coupled Si microstrip detectors

    International Nuclear Information System (INIS)

    Bacchetta, N.; Gotra, Yu.; Bisello, D.; Da Ros, R.; Giraldo, A.; Fusaro, G.; Paccagnella, A.; Univ. di Cagliari; Verzellesi, G.; Univ. di Padova

    1993-01-01

    The radiation response of FOXFETs has been studied for proton, gamma and neutron exposures. The punch-through behavior, which represents the normal FET operating conditions in Si microstrip detectors, has been found to be much less sensitive to radiation damage than threshold voltage. The device performance has been elucidated by means of two-dimensional simulations. The main radiation effects have been also taken into account in the numerical analysis and separately examined

  10. Damage-Tolerant, Lightweight, High-Temperature Radiator for Nuclear Powered Spacecraft

    Data.gov (United States)

    National Aeronautics and Space Administration — Game-changing propulsion systems are often enabled by novel designs using advanced materials. Radiator performance dictates power output for nuclear electric...

  11. The tolerance of skin grafts to postoperative radiation therapy in patients with soft-tissue sarcoma

    International Nuclear Information System (INIS)

    Lawrence, W.T.; Zabell, A.; McDonald, H.D.

    1986-01-01

    During the last ten years at the National Cancer Institute, 11 patients have received 12 courses of postoperative adjuvant radiation therapy to skin grafts used for wound closure after the resection of soft-tissue sarcomas. The intervals between grafting and the initiation of radiation ranged between 3 and 20 weeks, and 4 patients received chemotherapy at the same time as their radiation. Ten of the 12 irradiated grafts remained intact after the completion of therapy. One graft had several small persistently ulcerated areas that required no further surgical treatment, and one graft required a musculocutaneous flap for reconstruction of a persistent large ulcer. Acute radiation effects on the grafted skin sometimes developed at slightly lower doses than usually seen with normal skin, but these acute effects necessitated a break in therapy on only five occasions. Concurrent chemotherapy and a relatively short interval between grafting and the initiation of radiation seemed to contribute to more severe radiation reactions. This experience indicates that postoperative adjuvant radiation therapy can be delivered to skin grafted areas without undue fear of complications, especially if the graft is allowed to heal adequately prior to initiating therapy and if chemotherapy is not given in conjunction with radiation

  12. Radiation-hardened gate-around n-MOSFET structure for radiation-tolerant application-specific integrated circuits

    International Nuclear Information System (INIS)

    Lee, Min Su; Lee, Hee Chul

    2012-01-01

    To overcome the total ionizing dose effect on an n-type metal-oxide-semiconductor field-effect transistor (n-MOSFET), we designed a radiation-hardened gate-around n-MOSFET structure and evaluated it through a radiation-exposure experiment. Each test device was fabricated in a commercial 0.35-micron complementary metal-oxide-semiconductor (CMOS) process. The fabricated devices were evaluated under a total dose of 1 Mrad (Si) at a dose rate of 250 krad/h to obtain very high reliability for space electronics. The experimental results showed that the gate-around n-MOSFET structure had very good performance against 1 Mrad (Si) of gamma radiation, while the conventional n-MOSFET experienced a considerable amount of radiation-induced leakage current. Furthermore, a source follower designed with the gate-around transistor worked properly at 1 Mrad (Si) of gamma radiation while a source follower designed with the conventional n-MOSFET lost its functionality.

  13. Radiation induced variation in potato for tolerance to salinity using tissue culture technique

    International Nuclear Information System (INIS)

    Sharabash, M.T.

    2001-01-01

    Meristem-tips of potato (Solanum tuberosum) cv. 'Diamant', obtained from tuber sprouts, were cultured on MS medium, and multiplied into plantlets through micropropagation. To induce variation for salt tolerance, the obtained plantlets were irradiated with 0, 20, and 40 Gy gamma rays at 27.7 rad/sec. Irradiated plantlets were cut into single nodes and cultured on MS medium, supplemented with 2000 and 4000 ppm NaCI. Salt tolerant plantlets were transferred for tuberization on MS liquid medium supplemented with the same concentration of NaCI. Micro-tubers, collected after 6 weeks of culture, had fresh weight between 0.03 to 0.3 g. Mini-tubers were obtained by planting micro-tubers in 25 cm pots under insect proof greenhouse. Mini-tuber number per plant ranged from 3 to 6, and the mini-tuber weight ranged from 0.5-3.0 g, depending upon the treatment. Further studies are in progress to produce conventional tubers under salinity stress from the promising variants, specially those tolerant to 4000 ppm, and to assure the stability of the obtained variants. (author)

  14. The effect of gamma radiation from sources "6"0Co of soybean for shade tolerant

    International Nuclear Information System (INIS)

    Lilik Harsanti; Yulidar

    2016-01-01

    Gamma rays are electromagnetic waves that have a very strong penetrating power. One of the sources of gamma rays is from "6"0Co. The gamma rays have strong penetration power can be used of plant breeding to create new genetic diversity in the make of high-yielding varieties. Irradiation of gamma rays at a dose of 300 gray and 400 gray on soybean Denna 1 seed varieties has been done, then it was planted as M.1 the plants look healthy and robust and strong stems. The parameters observed plant height, sum book leaf, sum seed, sum pod and Percentage plant to live shade tolerant. The parameters observed were good: plant height doze 300 Gy (37.76 cm) and 400 gray (33.03 cm) The number of branches with doze 300 Gy (1.75) and 400 Gy (1.95), number of pod with doze 300 Gy (26.25) and 400 Gy (24.72), number of seed with doze 300 Gy (35.55 kg) and 400 Gy (33.65 kg), number of Naut with doze 300 Gy (9.28) and 400 Gy (8.53) and the percentage of plants capable of shade tolerant with doze 300 Gy (85) and 400 Gy(75). In conclusion, selection mutant lines of soybeans shade tolerant at generation M1 and next generation. (author)

  15. High Resolution, Radiation Tolerant Focal Plane Array for Lunar And Deep Space Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Aerius Photonics and its partners propose the development of a high resolution, radiation hardened 3-D FLASH Focal Plane Array (FPA), with performance expected to be...

  16. Radiation-Tolerant Reprogrammable FPGA for Digital Signal Processing Circuits, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Field Programmable Gate Arrays are a widely used technology; however, they are generally limited in reprogrammability. Radiation hard, low power and high density...

  17. Radiation Tolerance of A2Ti2O7 Materials - A Question of Bonding?

    International Nuclear Information System (INIS)

    Whittle, Karl R.; Lumpkin, Gregory R.; Smith, Katherine L.; Blackford, Mark G.; Harvey, Elizabeth J.; Zaluzec, Nestor J.

    2007-01-01

    The resistance of Ln 2 Ti 2 O 7 (Ln = lanthanide) compounds to radiation damage is an important topic in the understanding and development of new materials by which radioactive nuclear waste can safely be immobilised. A model has been developed, from previously published density functional theory and molecular orbital theory simulations of the band structure for Ln 2 Ti 2 O 7 materials. This model provides a chemical interpretation of radiation stability. (authors)

  18. Preliminary Results on FeCrAl Alloys in the As-received and Welded State Designed to Have Enhanced Weldability and Radiation Tolerance

    International Nuclear Information System (INIS)

    Field, Kevin G.; Gussev, Maxim N.; Hu, Xunxiang; Yamamoto, Yukinori

    2015-01-01

    The present report summarizes and discusses the recent results on developing a modern, nuclear grade FeCrAl alloy designed to have enhanced radiation tolerance and weldability. The alloys used for these investigations are modern FeCrAl alloys based on a Fe-13Cr-5Al-2Mo-0.2Si-0.05Y alloy (in wt.%, designated C35M). Development efforts have focused on assessing the influence of chemistry and microstructure on the fabricability and performance of these newly developed alloys. Specific focus was made to assess the weldability, thermal stability, and radiation tolerance.

  19. Preliminary Results on FeCrAl Alloys in the As-received and Welded State Designed to Have Enhanced Weldability and Radiation Tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hu, Xunxiang [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-30

    The present report summarizes and discusses the recent results on developing a modern, nuclear grade FeCrAl alloy designed to have enhanced radiation tolerance and weldability. The alloys used for these investigations are modern FeCrAl alloys based on a Fe-13Cr-5Al-2Mo-0.2Si-0.05Y alloy (in wt.%, designated C35M). Development efforts have focused on assessing the influence of chemistry and microstructure on the fabricability and performance of these newly developed alloys. Specific focus was made to assess the weldability, thermal stability, and radiation tolerance.

  20. Lead tolerance and cellular distribution in Elsholtzia splendens using synchrotron radiation micro-X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie [MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Tian, Shengke [MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); University of Florida, Institute of Food and Agricultural Science, Indian River Research and Education Center, Fort Pierce, FL 34945 (United States); Lu, Lingli; Shohag, M.J.I.; Liao, Haibing [MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Yang, Xiaoe, E-mail: xyang@zju.edu.cn [MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Elsholtzia splendens had a good ability of lead tolerance and accumulation. Black-Right-Pointing-Pointer Pb was mostly restricted to the vascular bundles and epidermis tissues. Black-Right-Pointing-Pointer Pb and Ca shared most similar distribution patterns in E. splendens. - Abstract: Hydroponic experiments were conducted to investigate the tolerance and spatial distribution of lead (Pb) in Elsholtzia splendens-a copper (Cu) accumulator plant using synchrotron-based micro-X-ray fluorescence. According to chlorophyll concentration and chlorophyll fluorescence parameters, E. splendens displayed certain tolerance at 100 {mu}M Pb treatment. Lead concentration in roots, stems and leaves of E. splendens reached 45,183.6, 1657.6, and 380.9 mg kg{sup -1}, respectively. Pb was mostly accumulated in the roots, and there were also high concentrations of Pb been transported into stems and leaves. Micro-XRF analysis of the stem and leaf cross section revealed that Pb was mostly restricted in the vascular bundles and epidermis tissues of both stem and leaf of E. splendens. The correlation between distribution of K, Ca, Zn and Pb were analyzed. There were significant positive correlations (P < 0.01) among Pb and Ca, K, Zn distribution both in stem and leaf of E. splendens. However, among the three elements, Ca shared the most similar distribution pattern and the highest correlation coefficients with Pb in both stem and leaf cross section of E. splendens. This suggests that Ca may play an important role in Pb accumulation in stem and leaf of E. splendens.

  1. A radiation tolerant Data link board for the ATLAS Tile Cal upgrade

    Science.gov (United States)

    Åkerstedt, H.; Bohm, C.; Muschter, S.; Silverstein, S.; Valdes, E.

    2016-01-01

    This paper describes the latest, full-functionality revision of the high-speed data link board developed for the Phase-2 upgrade of ATLAS hadronic Tile Calorimeter. The link board design is highly redundant, with digital functionality implemented in two Xilinx Kintex-7 FPGAs, and two Molex QSFP+ electro-optic modules with uplinks run at 10 Gbps. The FPGAs are remotely configured through two radiation-hard CERN GBTx deserialisers (GBTx), which also provide the LHC-synchronous system clock. The redundant design eliminates virtually all single-point error modes, and a combination of triple-mode redundancy (TMR), internal and external scrubbing will provide adequate protection against radiation-induced errors. The small portion of the FPGA design that cannot be protected by TMR will be the dominant source of radiation-induced errors, even if that area is small.

  2. High-Intensity Radiated Field Fault-Injection Experiment for a Fault-Tolerant Distributed Communication System

    Science.gov (United States)

    Yates, Amy M.; Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Gonzalez, Oscar R.; Gray, W. Steven

    2010-01-01

    Safety-critical distributed flight control systems require robustness in the presence of faults. In general, these systems consist of a number of input/output (I/O) and computation nodes interacting through a fault-tolerant data communication system. The communication system transfers sensor data and control commands and can handle most faults under typical operating conditions. However, the performance of the closed-loop system can be adversely affected as a result of operating in harsh environments. In particular, High-Intensity Radiated Field (HIRF) environments have the potential to cause random fault manifestations in individual avionic components and to generate simultaneous system-wide communication faults that overwhelm existing fault management mechanisms. This paper presents the design of an experiment conducted at the NASA Langley Research Center's HIRF Laboratory to statistically characterize the faults that a HIRF environment can trigger on a single node of a distributed flight control system.

  3. Analysis of the Failures and Corrective Actions for the LHC Cryogenics Radiation Tolerant Electronics and its Field Instruments

    CERN Document Server

    Balle, Ch; Vauthier, N

    2014-01-01

    The LHC cryogenic system radiation tolerant electronics and their associated field instruments have been in nominal conditions since before the commissioning of the first LHC beams in September 2008. This system is made of about 15’000 field instruments (thermometers, pressure sensors, liquid helium level gauges, electrical heaters and position switches), 7’500 electronic cards and 853 electronic crates. Since mid-2008 a software tool has been deployed, this allows an operator to report a problem and then lists the corrective actions. The tool is a great help in detecting recurrent problems that may be tackled by a hardware or software consolidation. The corrective actions range from simple resets, exchange of defective equipment, repair of electrical connectors, etc. However a recurrent problem that heals by itself is present on some channels. This type of fault is extremely difficult to diagnose and it appears as a temporary opening of an electrical circuit; its duration can range from a few minutes to ...

  4. Fractionated radiation therapy in the treatment of intracranial meningiomas: local control, functional efficacy, and tolerance in 91 patients

    International Nuclear Information System (INIS)

    Maire, Jean-Philippe; Caudry, Michel; Guerin, Jean; Celerier, Denis; San Galli, Francois; Causse, Nicole; Trouette, Renaud; Dautheribes, Michel

    1995-01-01

    Purpose: To evaluate efficacy and tolerance of external fractionated radiation therapy (RT) in the treatment of intracranial meningiomas. Methods and Materials: From January 1981 to September 1993, 91 patients with intracranial meningiomas were treated with fractionated RT. Indications were as follows: (a) incomplete surgical resection, 29 patients; (b) tumor recurrences without considering the amount of the second resection, if performed, 14 patients; (c) completely excised angioblastic, aggressive benign, and anaplastic tumors, 8 patients; (d) medically inoperable and basilar tumors where operation would involve considerable danger or permanent neurological damage, 44 patients. Most patients were irradiated with 6 to 9 MV photon beams. A three- to four-field technique with coned-down portals was used. Doses were calculated on the 95% isodose and were given 5 days a week for a median total dose of 52 Gy (1.80 Gy/fraction). Results: Median follow-up from radiation therapy was 40 months. Acute tolerance was excellent, but there were six late delayed injuries. Tumor recurrences occurred in six cases. Six patients died from their tumor or RT complications, 19 from nontumoral reasons. Three, 5- and 10-year survival rates were 82, 71, and 40%, respectively. The most significant prognostic factor was age: 5-year survival rate was 86% for patients less than 65 years and 37% for patients more than 65. However, there were no differences in recurrence-free survival rates between patients younger than 65 and the oldest ones. Of 60 symptomatic patients with neurological deficits, 43 had neurological improvement (72%), beginning in some cases within 15 to 20 days after starting RT. Conclusion: These results reassess the role of fractionated RT in the treatment of meningiomas, and stress on its efficacy, especially on cranial nerves palsies, without severe toxicity in most cases

  5. LHCb: Radiation tolerance tests of SRAM-based FPGAs for the possible usage in the readout electronics for the LHCb experiment

    CERN Multimedia

    Faerber, C; Wiedner, D; Leveringzon, B; Ekelhof, R

    2013-01-01

    This paper describes radiation studies of SRAM-based FPGAs as a central component of the electronics for a possible upgrade of the LHCb Outer Tracker readout electronics to a frequency of 40 MHz. Two Arria GX FPGAs were irradiated with 20 MeV protons to radiation doses of up to 7 Mrad. During and between the irradiation periods the different FPGA currents, the package temperature, the firmware error rate, the PLL stability, and the stability of a 32 channel TDC implemented on the FPGA were monitored. Results on the radiation tolerance of the FPGA and the measured firmware error rates will be presented. The Arria GX FPGA fulfils the radiation tolerance required for the LHCb upgrade (30 krad) and an expected firmware error rate of 10$^{-6}$ Hz makes the chip viable for the LHCb Upgrade.

  6. Heat- and radiation-induced radio- and thermo-tolerance of Zea mays seedlings

    International Nuclear Information System (INIS)

    Gikoshvili, T.I.; Vagabova, M.Eh.; Vilenchik, M.M.; Kuzin, A.M.

    1985-01-01

    It was shown that γ-irradiation of Zea mays seedlings with low doses (1-3 Gy) induced thermotolerance, and preheating up to 43 deg C increased their radioresistance and thermotolerance. A hypothesis of the formation of common protective proteins after exposure to low - level radiation and heat is discussed

  7. Long-term tolerance and outcomes for dose escalation in early salvage post-prostatectomy radiation therapy

    International Nuclear Information System (INIS)

    Safdieh, Joseph; Schwartz, David; Weiner, Joseph; Weiss, Jeffrey P.; Madeb, Isaac; Rotman, Marvin; Schreiber, David; Rineer, Justin

    2014-01-01

    To study the long-term outcomes and tolerance in our patients who received dose escalated radiotherapy in the early salvage post-prostatectomy setting. The medical records of 54 consecutive patients who underwent radical prostatectomy subsequently followed by salvage radiation therapy (SRT) to the prostate bed between 2003-2010 were analyzed. Patients included were required to have a pre-radiation prostate specific antigen level (PSA) of 2 ng/mL or less. The median SRT dose was 70.2 Gy. Biochemical failure after salvage radiation was defined as a PSA level >0.2 ng/mL. Biochemical control and survival endpoints were analyzed using the Kaplan-Meier method. Univariate and multivariate Cox regression analysis were used to identify the potential impact of confounding factors on outcomes. The median pre-SRT PSA was 0.45 ng/mL and the median follow-up time was 71 months. The 4- and 7-year actuarial biochemical control rates were 75.7% and 63.2%, respectively. The actuarial 4- and 7-year distant metastasis-free survival was 93.7% and 87.0%, respectively, and the actuarial 7-year prostate cancer specific survival was 94.9%. Grade 3 late genitourinary toxicity developed in 14 patients (25.9%), while grade 4 late genitourinary toxicity developed in 2 patients (3.7%). Grade 3 late gastrointestinal toxicity developed in 1 patient (1.9%), and grade 4 late gastrointestinal toxicity developed in 1 patient (1.9%). In this series with long-term follow-up, early SRT provided outcomes and toxicity profiles similar to those reported from the three major randomized trials studying adjuvant radiation therapy.

  8. Radiation tolerance of a spin-dependent tunnelling magnetometer for space applications

    International Nuclear Information System (INIS)

    Persson, Anders; Thornell, Greger; Nguyen, Hugo

    2011-01-01

    To meet the increasing demand for miniaturized space instruments, efforts have been made to miniaturize traditional magnetometers, e.g. fluxgate and spin-exchange relaxation-free magnetometers. These have, for different reasons, turned out to be difficult. New technologies are needed, and promising in this respect are tunnelling magnetoresistive (TMR) magnetometers, which are based on thin film technology. However, all new space devices first have to be qualified, particularly in terms of radiation resistance. A study on TMR magnetometers' vulnerability to radiation is crucial, considering the fact that they employ a dielectric barrier, which can be susceptible to charge trapping from ionizing radiation. Here, a TMR-based magnetometer, called the spin-dependent tunnelling magnetometer (SDTM), is presented. A magnetometer chip consisting of three Wheatstone bridges, with an angular pitch of 120°, was fabricated using microstructure technology. Each branch of the Wheatstone bridges consists of eight pairs of magnetic tunnel junctions (MTJs) connected in series. Two such chips are used to measure the three-dimensional magnetic field vector. To investigate the SDTM's resistance to radiation, one branch of a Wheatstone bridge was irradiated with gamma rays from a Co 60 source with a dose rate of 10.9 rad min −1 to a total dose of 100 krad. The TMR of the branch was monitored in situ, and the easy axis TMR loop and low-frequency noise characteristics of a single MTJ were acquired before and after irradiation with the total dose. It was concluded that radiation did not influence the MTJs in any noticeable way in terms of the TMR ratio, coercivity, magnetostatic coupling or low-frequency noise

  9. Radiation tolerance of nanostructured ZrN coatings against swift heavy ion irradiation

    International Nuclear Information System (INIS)

    Janse van Vuuren, A.; Skuratov, V.A.; Uglov, V.V.; Neethling, J.H.; Zlotski, S.V.

    2013-01-01

    Nano-structured zirconium nitride layers – on Si substrates – of various thicknesses (0.1, 3, 10 and 20 μm) were irradiated with 167 MeV Xe, 250 MeV Kr and 695 MeV Bi ions to fluences in the range from 3 × 10 12 to 2.6 × 10 15 cm −2 for Xe, 1 × 10 13 to 7.06 × 10 13 cm −2 for Kr and 10 12 to 10 13 cm −2 for Bi. The purpose of these irradiation experiments is to simulate the effects of fission fragment bombardment on nanocrystalline ZrN. The irradiated layers where subsequently analysed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and nano-indentation hardness testing (NIH) techniques. XRD, TEM and NIH results indicate that ZrN has a very high tolerance to the effects of high energy irradiation

  10. Infusion of donor lymphocytes into stable canine radiation chimeras: implications for mechanism of transplantation tolerance

    International Nuclear Information System (INIS)

    Weiden, P.L.; Storb, R.; Tsoi, M.S.; Graham, T.C.; Lerner, K.G.; Thomas, E.D.

    1976-01-01

    Canine radiation chimeras were used to investigate further mechanism(s) responsible for maintaining the stable chimeric state. In an attempt to elucidate the nature of this postulated active mechanism, the cytotoxicity of donor lymphocytes for fibroblasts of the chimera and the presence or absence of serum-blocking factors were assessed in vitro by using a cellular inhibition (CI) assay. The presence of serum-blocking factors did not protect against the development of significant GVHD in two chimeras (fatal in one). GVHD did not occur in four other chimeras after infusion of cytotoxic donor lymphocytes despite the absence of serum-blocking factors. These and previous results suggest that serum-blocking factors are not the mechanism suppressing the development of GVHD in canine radiation chimeras, and raise the possibility that a suppressor cell population may be responsible for preventing GVHD

  11. Second Annual Progress Report on Radiation Tolerance of Controlled Fusion Welds in High Temperature Oxidation Resistant FeCrAl Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Richard H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Briggs, Samuel A. [Univ. of Wisconsin, Madison, WI (United States)

    2016-12-30

    The present report summarizes and discusses the current results and on-going activity towards developing a modern, nuclear grade FeCrAl alloy designed to have enhanced radiation tolerance and weldability under the Department of Energy (DOE) Nuclear Energy Enabling Technologies (NEET) program.

  12. The GBT-SCA, a radiation tolerant ASIC for detector control and monitoring applications in HEP experiments

    International Nuclear Information System (INIS)

    Caratelli, A.; Bonacini, S.; Kloukinas, K.; Marchioro, A.; Moreira, P.; Oliveira, R. De; Paillard, C.

    2015-01-01

    The future upgrades of the LHC experiments will increase the beam luminosity leading to a corresponding growth of the amounts of data to be treated by the data acquisition systems. To address these needs, the GBT (Giga-Bit Transceiver optical link [1,2]) architecture was developed to provide the simultaneous transfer of readout data, timing and trigger signals as well as slow control and monitoring data. The GBT-SCA ASIC, part of the GBT chip-set, has the purpose to distribute control and monitoring signals to the on-detector front-end electronics and perform monitoring operations of detector environmental parameters. In order to meet the requirements of different front-end ASICs used in the experiments, it provides various user-configurable interfaces capable to perform simultaneous operations. It is designed employing radiation tolerant design techniques to ensure robustness against SEUs and TID radiation effects and is implemented in a commercial 130 nm CMOS technology. This work presents the GBT-SCA architecture, the ASIC interfaces, the data transfer protocol, and its integration with the GBT optical link

  13. High-Speed, Radiation-Tolerant Laser Drivers in 0.13 $\\mu$m CMOS Technology for HEP Applications

    CERN Document Server

    AUTHOR|(CDS)2073369; Moreira, Paulo; Calvo, Daniela; De Remigis, Paolo; Olantera, Lauri; Soos, Csaba; Troska, Jan; Wyllie, Ken

    2014-01-01

    The gigabit laser driver (GBLD) and low-power GBLD (LpGBLD) are two radiation-tolerant laser drivers designed to drive laser diodes at data rates up to 4.8 Gb/s. They have been designed in the framework of the gigabit-transceiver (GBT) and versatile-link projects to provide fast optical links capable of operation in the radiation environment of future high-luminosity high-energy physics experiments. The GBLD provides laser bias and modulation currents up to 43 mA and 24 mA, respectively. It can thus be used to drive vertical cavity surface emitting laser (VCSEL) and edge-emitting laser diodes. A pre-emphasis circuit, which can provide up to 12 mA in 70 ps pulses, has also been implemented to compensate for high external capacitive loads. The current driving capabilities of the LpGBLD are 2 times smaller that those of the GBLD as it has been optimized to drive VCSELs in order to minimize the power consumption. Both application-specific integrated circuits are designed in 0.13 m commercial complementary metal-o...

  14. Antiradiation Vaccine: Technology Development- Radiation Tolerance,Prophylaxis, Prevention And Treatment Of Clinical Presentation After Heavy Ion Irradiation.

    Science.gov (United States)

    Popov, Dmitri; Maliev, Slava; Jones, Jeffrey

    Introduction: Research in the field of biological effects of heavy charged particles is necessary for both heavy-ion therapy (hadrontherapy) and protection from the exposure to galactic cosmic radiation in long-term manned space missions.[Durante M. 2004] In future crew of long-term manned missions could operate in exremely high hadronic radiation areas of space and will not survive without effective radiation protection. An Antiradiation Vaccine (AV) must be an important part of a countermeasures regimen for efficient radiation protection purposes of austronauts-cosmonauts-taukonauts: immune-prophylaxis and immune-therapy of acute radiation toxic syndromes developed after heavy ion irradiation. New technology developed (AV) for the purposes of radiological protection and improvement of radiation tolerance and it is quite important to create protective immune active status which prevent toxic reactions inside a human body irradiated by high energy hadrons.[Maliev V. et al. 2006, Popov D. et al.2008]. High energy hadrons produce a variety of secondary particles which play an important role in the energy deposition process, and characterise their radiation qualities [Sato T. et al. 2003] Antiradiation Vaccine with specific immune-prophylaxis by an anti-radiation vaccine should be an important part of medical management for long term space missions. Methods and experiments: 1. Antiradiation vaccine preparation standard, mixture of toxoid form of Radiation Toxins [SRD-group] which include Cerebrovascular RT Neurotoxin, Cardiovascular RT Neurotoxin, Gastrointestinal RT Neurotoxin, Hematopoietic RT Hematotoxin. Radiation Toxins of Radiation Determinant Group isolated from the central lymph of gamma-irradiated animals with Cerebrovascular, Cardiovascular, Gastro-intestinal, Hematopoietic forms of ARS. Devices for radiation are "Panorama", "Puma". 2. Heavy ion exposure was accomplished at Department of Research Institute of Nuclear Physics, Dubna, Russia. The heavy ions

  15. Normal tissue tolerance to external beam radiation therapy: Adult bone; Dose de tolerance a l'irradiation des tissus sains: l'os chez l'adulte

    Energy Technology Data Exchange (ETDEWEB)

    Sargos, P.; Mamou, N.; Dejean, C.; Henriques de Figueiredo, B.; Kantor, G. [Departement de radiotherapie, Centre regional de lutte contre le cancer, institut Bergonie, 33 - Bordeaux (France); Huchet, A. [Departement de radiotherapie, hopital Saint-Andre, 33 - Bordeaux (France); Italiano, A. [Service d' oncologie medicale, Centre regional de lutte contre le cancer, institut Bergonie, 33 - Bordeaux (France)

    2010-07-15

    Radiation tolerance for bone tissue has been mostly evaluated with regard to bone fracture. Main circumstances are mandibula osteoradionecrosis, hip and costal fracture, and patent or radiologic fractures in the treated volume. After radiation therapy of bone metastasis, the analysis of related radiation fracture is difficult to individualize from a pathologic fracture. Frequency of clinical fracture is less than 5% in the large series or cohorts and is probably under-evaluated for the asymptomatic lesions. Women older than 50 years and with osteoporosis are probably the main population at risk. Dose-effect relations are difficult to qualify in older series. Recent models evaluating radiations toxicity on diaphysa suggest an important risk after 60 Gy, for high dose-fraction and for a large volume. (authors)

  16. Construction tolerances for low loss, dielectric coated, metallic waveguide for transmission optical radiation

    International Nuclear Information System (INIS)

    Sandweiss, J.

    1984-08-01

    The transmission of radiation, in a specific mode of interest for the IFELA, past a symmetric step in dielectric coating thickness has been calculated. The result shows that the transmission loss depends on the quantity (s/D) 2 and vanishes to first order in the ratio of the step s to the guide aperture D. With the reasonable assumption that this feature holds for all forms of surface imperfections, the attenuation length due to imperfections has been estimated. It is found that rms surface roughness of approx. 0.1 μ m leads to attenuation lengths of 25 km or greater

  17. Tolerance of the different structures of the eye to therapeutic ionizing radiation

    International Nuclear Information System (INIS)

    Fernandez-Vicioso, E.; Ruiz-Cruces, R.; Faulkner, K.

    2001-01-01

    Primary tumours of the visual apparatus are rare, although radiation therapy of tumours near the eye is becoming increasingly more common in daily practice. These tumours often incur the incidental irradiation of eye structures, even when the latter are not clinically involved with the tumour. Depending on the dose and irradiated volume some damage to the different structures of the visual apparatus may occur. In addition, the time to expression and severity of injury are dose-dependent. This review analyses the most recent literature and proposes daily practice guidelines. (author)

  18. Radiation tolerance of nanostructured ZrN coatings against swift heavy ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Janse van Vuuren, A., E-mail: arnojvv@gmail.com [Centre for HRTEM, Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth (South Africa); Skuratov, V.A. [Flerov Laboratory for Nuclear Reactions, Joint Institute for Nuclear Research, Dubna (Russian Federation); Uglov, V.V. [Department of Solid State Physics, Physics Faculty Belarusian State University, Minsk (Belarus); Neethling, J.H. [Centre for HRTEM, Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth (South Africa); Zlotski, S.V. [Department of Solid State Physics, Physics Faculty Belarusian State University, Minsk (Belarus)

    2013-11-15

    Nano-structured zirconium nitride layers – on Si substrates – of various thicknesses (0.1, 3, 10 and 20 μm) were irradiated with 167 MeV Xe, 250 MeV Kr and 695 MeV Bi ions to fluences in the range from 3 × 10{sup 12} to 2.6 × 10{sup 15} cm{sup −2} for Xe, 1 × 10{sup 13} to 7.06 × 10{sup 13} cm{sup −2} for Kr and 10{sup 12} to 10{sup 13} cm{sup −2} for Bi. The purpose of these irradiation experiments is to simulate the effects of fission fragment bombardment on nanocrystalline ZrN. The irradiated layers where subsequently analysed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and nano-indentation hardness testing (NIH) techniques. XRD, TEM and NIH results indicate that ZrN has a very high tolerance to the effects of high energy irradiation.

  19. In vitro induction of variation through radiation for late blight resistance and heat tolerance in potato

    Energy Technology Data Exchange (ETDEWEB)

    Minocha, J L; Das, A; Gopal, J; Gosal, S S [Biotechnology Centre, Punjab Agricultural Univ., Ludhiana, Punjab (India)

    1997-07-01

    In vitro plants were obtained from nodal sections of sprouts of cvs. `Kufri Jyoti` and `Kufri Chandramukhi` of potato cultured on MS medium with 3% sucrose. Callus from leaves of in vitro cultured plantlets was induced on modified Linsmaier and Skoog medium supplemented with 5 mg/1 NAA. The obtained shoots and calli were irradiated with 20 and 40 Gy gamma rays. Irradiatied shoots were transferred to MS medium with 8% sucrose for multiplication, and then to MS medium with 8% sucrose and 10 mg/1 BAP to induce microtuber formation, which gave on average 1.3 microtubers per plant. The microtubers were planted in pots and variation was observed in plant morphology and tuber characters. To study variation for late blight resistance, irradiated calli were kept on Gamborg B-5 medium with culture filtrate of Phytophthora infestans. To induce variation for heat tolerance, in vitro shoots from irradiated material were mass-propagated and allowed to produce microtubers at high temperature. (author). 3 refs, 3 tabs.

  20. In vitro induction of variation through radiation for late blight resistance and heat tolerance in potato

    International Nuclear Information System (INIS)

    Minocha, J.L.; Das, A.; Gopal, J.; Gosal, S.S.

    1997-01-01

    In vitro plants were obtained from nodal sections of sprouts of cvs. 'Kufri Jyoti' and 'Kufri Chandramukhi' of potato cultured on MS medium with 3% sucrose. Callus from leaves of in vitro cultured plantlets was induced on modified Linsmaier and Skoog medium supplemented with 5 mg/1 NAA. The obtained shoots and calli were irradiated with 20 and 40 Gy gamma rays. Irradiatied shoots were transferred to MS medium with 8% sucrose for multiplication, and then to MS medium with 8% sucrose and 10 mg/1 BAP to induce microtuber formation, which gave on average 1.3 microtubers per plant. The microtubers were planted in pots and variation was observed in plant morphology and tuber characters. To study variation for late blight resistance, irradiated calli were kept on Gamborg B-5 medium with culture filtrate of Phytophthora infestans. To induce variation for heat tolerance, in vitro shoots from irradiated material were mass-propagated and allowed to produce microtubers at high temperature. (author). 3 refs, 3 tabs

  1. Design of an FPGA-based Radiation Tolerant Agent for Worldfip Fieldbus

    CERN Document Server

    Penacoba, G; Gousiou, E; Page, S; Palluel, J; Serrano, J; van der Bij, E

    2011-01-01

    CERN makes extensive use of the WorldFIP fieldbus interface in the LHC and other accelerators in the preinjectors chain. Following the decision of the provider of the components to stop the developments in this field and foreseeing the potential problems in the subsequent support, CERN decided to purchase the design information of these components and in-source the future developments using this technology. The first in-house design concerns a replacement for the MicroFIP chip whose last version was manufactured in an IC feature size found to be more vulnerable to radiation of high energy particles than the previous versions. NanoFIP is a CERN design based on a Flash FPGA implementing a subset of the functionality allowed by the communication standard, fitting the requirements of the different users and including the robustness against radiation as a design constraint. The development presented involved several groups at CERN working together in the framework of the Open Hardware Repository collaboration, and...

  2. Physiological factors affecting renal radiation tolerance: a guide to the treatment of late effects

    International Nuclear Information System (INIS)

    Robbins, M.E.C.; Hopewell, J.W.

    1986-01-01

    The results presented provide preliminary information concerning the ability of vasoactive compounds to modify the reduction in renal haemodynamics following renal irradiation. The two compounds are widely used in the clinical treatment of hypertension. The radiation-induced changes in glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) observed in bilaterally irradiated pigs which received 150 mg indoramin daily were similar to those seen in pigs which received radiation alone: if anything the former exhibited greater decline in renal function. Two of the three Captopril-treated animals appeared to show a reduced impairment of renal function compared with irradiated controls. It is not known why the remaining pig did not show a similar response. However, plasma renin levels in this pig, measured 10 weeks after irradiation, were markedly higher than in the other two animals, i.e. 10.7 compared with 2.3 and 4.5 pmol -1 ml -1 , possibly reflecting greater renal damage. The total renal weight at postmortem of this pig was considerably reduced (approx. 50%), whereas the renal weights of the remaining Captopril-treated pigs were similar to those of age-related controls. (UK)

  3. Proposal of low-cost COTS safety MCU for radiation tolerant controls in CBM detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lucio Martinez, Jose Antonio; Kebschull, Udo [Infrastructure and Computer Systems in Data Processing, Goethe University Frankfurt (Germany); Collaboration: CBM-Collaboration

    2016-07-01

    Amid general necessity of a robust slow control system for detectors, a DCS board with a cheap COTS MCU conceived for safety critical applications, and that supports conventional RTEMS+EPICS, is being designed for hostile environments. E.g. To operate inside detectors. For this purpose such MCU, which has redundancy features like lockstep run and ECC-SECDED error correction on flash and SRAM internal memories, was tested under radiation condition at the SPS beamtime parasitically to a detector test in CERN. In this preliminary beam-test, RTEMS+EPICS simplifies controls management and in this case supported data acquisition by monitoring the fault registers of the MCU and transmitting them with the ethernet interface, as a backup method the JTAG was used to inspect such registers to confirm the register reads. The results suggest that this is a reliable MCU for hostile conditions.

  4. Peripheral nerve and ureteralo tolerance to intraoperative radiation therapy; Clinical and dose-response analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, E.G.; Gunderson, L.L.; Martin, J.K.; Baers, R.W.; Nagorney, D.M.; Podratz, K.C. (Mayo Clinic, Rochester, MN (USA))

    1990-07-01

    Between April 1981 and July 1984, 51 received intraoperative radiation therapy (IORT) as a component of therapy for the management of primary of recurrent pelvic malignancies which were initially unresectable for cure. For these patients, curative surgical alternatives did not exist, or would have involved extensive procedures such as pelvic exenteration, distal sacrectomy, hemipelvectomy, or hemicorporectemy. The primary disease was colorectal in 38 patients. Treatment consisted of external beam radiation (range 3000 to 6890 cGy, median 5040 cGy), surgical debulking when feasible, and an intraoperative electron beam boost to the gross of microscopic residual desease (dose range 1000 to 2500 cGy, median 1750 cGy) utilizing 9-18 MeV electrons. The most common IORT associated toxicities were peripheral neurophaty and ureteral obstruction. None were life-threatening or fatal in severity. Of the 50 patients evaluable for neurotoxicity analysis, 16 (32%) developed peripheral neurophaty consisting of pain in 16 patients, numbness and tingling in 11, and weakness in 8. The pain, numbness and tingling resolved in about 40% of patients, while weakness resolved in only 1 of 8. Sixteen ureters were initially unobstructed by tumor at the time of IORT. Of these, 10 (63%) subsequently showed evidence of obstruction and hydronephrosis. The development of neurotoxicity was more common at IORT doses of 1500 cGy or more versus 1000 cGy. Ureteral obstruction with hydronephrosis occurred more frequently at IORT doses of 1250 cGy or more compared to 1000 cGy. There was no relationship between the likelihood of developing complications and the total external beam dose. The observed dependence of human nerve toxicity primarily on the IORT dose is consistent with data generated form animal experiments. (author). 21 refs.; 4 tabs.

  5. Radiation tolerance of the spinal cord previously-damaged by tumor operation: long term neurological improvement and time-dose-volume relationships after irradiation of intraspinal gliomas

    International Nuclear Information System (INIS)

    Kopelson, G.

    1982-01-01

    Of 26 patients with intramedullary spinal cord gliomas (9 astrocytomas, 5 glioblastomas, 12 ependymomas) seen at the Massachusetts General Hospital from 1962-1980, 24 were irradiated (21 initially and 3 after post-surgical recurrence). Those 19 patients who survived at least 1 year after completion of irradiation were evaluated for post-irradiation neurological changes.No patient developed radiation myelopathy. Return to a permanently and completely normal neurological status occured for 33/51 (65%) of pre-irradiation neurological deficits. The major cause of post-irradiation neurological deterioration was tumor recurrence. Although 18/19 patients had their thoracic or lumbar spinal cords irradiated, each with field sizes greater than 10 cm, spinal cord doses approaching, equalling, or occasionally exceeding various definitions of spinal cord tolerance were tolerated well without evidence of radiation myelopathy. Spinal cords of patients with intramedullary gliomas, often with major neurological deficits prior to irradiation, may be treated safely to doses approaching or equalling spinal cord tolerance levels. These doses are expected to locally control most ependymomas and astrocytomas without an increased radiation myelopathy. Caution should be observed if doses higher than this are contemplated in an attempt to cure glioblastoma, because the 5% tolerance level of the damaged spinal remains to be defined

  6. Experimental Evolution of UV-C Radiation Tolerance: Emergence of Adaptive and Non-Adaptive Traits in Escherichia coli Under Differing Flux Regimes

    Science.gov (United States)

    Moffet, A.; Okansinski, A.; Sloan, C.; Grace, J. M.; Paulino-Lima, I. G.; Gentry, D.; Rothschild, L. J.; Camps, M.

    2014-12-01

    High-energy ultraviolet (UV-C) radiation is a significant challenge to life in environments such as high altitude areas, the early Earth, the Martian surface, and space. As UV-C exposure is both a selection pressure and a mutagen, adaptation dynamics in such environments include a high rate of change in both tolerance-related and non-tolerance-related genes, as well changes in linkages between the resulting traits. Determining the relationship between the intensity and duration of the UV-C exposure, mutation rate, and emergence of UV-C resistance will inform our understanding of both the emergence of radiation-related extremophily in natural environments and the optimal strategies for generating artificial extremophiles. In this study, we iteratively exposed an Escherichia colistrain to UV-C radiation of two different fluxes, 3.3 J/m^2/s for 6 seconds and 0.5 J/m^2/s for 40 seconds, with the same overall fluence of 20 J/m^2. After each iteration, cells from each exposure regime were assayed for increased UV-C tolerance as an adaptive trait. The exposed cells carried a plasmid bearing a TEM beta-lactamase gene, which in the absence of antibiotic treatment is a neutral reporter for mutagenesis. Sequencing of this gene allowed us to determine the baseline mutation frequency for each flux. As an additional readout for adaptation, the presence of extended-spectrum beta-lactamase mutations was tested by plating UV-exposed cultures in cefotaxime plates. We observed an increase of approximately one-million-fold in UV-C tolerance over seven iterations; no significant difference between the two fluxes was found. Future work will focus on identifying the genomic changes responsible for the change in UV-C tolerance; determining the mechanisms of the emerged UV-C tolerance; and performing competition experiments between the iteration strains to quantify fitness tradeoffs resulting from UV-C adaptation.

  7. Epitaxial silicon detectors for particle tracking-Radiation tolerance at extreme hadron fluences

    International Nuclear Information System (INIS)

    Lindstroem, Gunnar; Dolenc, Irena; Fretwurst, Eckhart; Hoenniger, Frank; Kramberger, Gregor; Moll, Michael; Nossarzewska, Elsbieta; Pintilie, Ioana; Roeder, Ralf

    2006-01-01

    Diodes processed on n-type epitaxial silicon with a thickness of 25, 50 and 75 μm had been irradiated with reactor neutrons and high-energy protons (24 GeV/c) up to integrated fluences of Φ eq =10 16 cm -2 . Systematic experiments on radiation-induced damage effects revealed the following results: in contrast to standard and oxygen-enriched float zone (FZ) silicon devices no space charge sign inversion was observed after irradiation. It is shown that the radiation-generated concentration of deep acceptors, dominating the behavior of n-type FZ diodes, is compensated by creation of shallow donors. Thus a positive space charge is maintained throughout the irradiation up to the highest fluence and even during prolonged elevated-temperature annealing cycles. Defect analysis studies using thermally stimulated current measurements attribute the effect to a damage-induced shallow donor at E C -0.23 eV. It is argued that, as in the case of thermal donors, oxygen dimers, out diffusing from the Cz substrate during the diode processing, are responsible precursers. Results from extensive annealing experiments at elevated temperatures are verified by comparison with prolonged room-temperature annealing. These results showed that in contrast to FZ detectors, which always have to be cooled, room-temperature storage during beam off periods of future elementary particle physics experiments would even be beneficial for n-type epi-silicon detectors. A dedicated experiment at CERN-PS had successfully proven this expectation. It was verified, that in such a scenario the depletion voltage for the epi-detector could always be kept at a moderate level throughout the full S-LHC operation (foreseen upgrade of the large hadron collider). Practically no difference with respect to FZ-silicon devices was found in the damage-induced bulk generation current. The charge trapping measured with 90 Sr electrons (mip's) is also almost identical to what was expected. A charge collection efficiency of

  8. Epitaxial silicon detectors for particle tracking-Radiation tolerance at extreme hadron fluences

    Energy Technology Data Exchange (ETDEWEB)

    Lindstroem, Gunnar [Institute for Experimental Physics, University of Hamburg, Hamburg, 22761 (Germany)]. E-mail: gunnar.lindstroem@desy.de; Dolenc, Irena [Jozef Stefan Institute, University of Ljubljana, Ljubljana, 100 (Slovenia); Fretwurst, Eckhart [Institute for Experimental Physics, University of Hamburg, Hamburg, 22761 (Germany); Hoenniger, Frank [Institute for Experimental Physics, University of Hamburg, Hamburg, 22761 (Germany); Kramberger, Gregor [Jozef Stefan Institute, University of Ljubljana, Ljubljana, 100 (Slovenia); Moll, Michael [CERN, Geneva, 1211 (Switzerland); Nossarzewska, Elsbieta [ITME, Institute for Electronocs Materials Technology, Warsaw, 01919 (Poland); Pintilie, Ioana [National Institute of Materials Physics, Bucharest, 077125 (Romania); Roeder, Ralf [CiS Institute for Microsensors gGmbH, Erfurt, 99099 (Germany)

    2006-11-30

    Diodes processed on n-type epitaxial silicon with a thickness of 25, 50 and 75 {mu}m had been irradiated with reactor neutrons and high-energy protons (24 GeV/c) up to integrated fluences of {phi} {sub eq}=10{sup 16} cm{sup -2}. Systematic experiments on radiation-induced damage effects revealed the following results: in contrast to standard and oxygen-enriched float zone (FZ) silicon devices no space charge sign inversion was observed after irradiation. It is shown that the radiation-generated concentration of deep acceptors, dominating the behavior of n-type FZ diodes, is compensated by creation of shallow donors. Thus a positive space charge is maintained throughout the irradiation up to the highest fluence and even during prolonged elevated-temperature annealing cycles. Defect analysis studies using thermally stimulated current measurements attribute the effect to a damage-induced shallow donor at E {sub C}-0.23 eV. It is argued that, as in the case of thermal donors, oxygen dimers, out diffusing from the Cz substrate during the diode processing, are responsible precursers. Results from extensive annealing experiments at elevated temperatures are verified by comparison with prolonged room-temperature annealing. These results showed that in contrast to FZ detectors, which always have to be cooled, room-temperature storage during beam off periods of future elementary particle physics experiments would even be beneficial for n-type epi-silicon detectors. A dedicated experiment at CERN-PS had successfully proven this expectation. It was verified, that in such a scenario the depletion voltage for the epi-detector could always be kept at a moderate level throughout the full S-LHC operation (foreseen upgrade of the large hadron collider). Practically no difference with respect to FZ-silicon devices was found in the damage-induced bulk generation current. The charge trapping measured with {sup 90}Sr electrons (mip's) is also almost identical to what was expected

  9. Growth under visible light increases conidia and mucilage production and tolerance to UV-B radiation in the plant pathogenic fungus Colletotrichum acutatum.

    Science.gov (United States)

    de Menezes, Henrique D; Massola, Nelson S; Flint, Stephan D; Silva, Geraldo J; Bachmann, Luciano; Rangel, Drauzio E N; Braga, Gilberto U L

    2015-01-01

    Light conditions can influence fungal development. Some spectral wavebands can induce conidial production, whereas others can kill the conidia, reducing the population size and limiting dispersal. The plant pathogenic fungus Colletotrichum acutatum causes anthracnose in several crops. During the asexual stage on the host plant, Colletototrichum produces acervuli with abundant mucilage-embedded conidia. These conidia are responsible for fungal dispersal and host infection. This study examined the effect of visible light during C. acutatum growth on the production of conidia and mucilage and also on the UV tolerance of these conidia. Conidial tolerance to an environmentally realistic UV irradiance was determined both in conidia surrounded by mucilage on sporulating colonies and in conidial suspension. Exposures to visible light during fungal growth increased production of conidia and mucilage as well as conidial tolerance to UV. Colonies exposed to light produced 1.7 times more conidia than colonies grown in continuous darkness. The UV tolerances of conidia produced under light were at least two times higher than conidia produced in the dark. Conidia embedded in the mucilage on sporulating colonies were more tolerant of UV than conidia in suspension that were washed free of mucilage. Conidial tolerance to UV radiation varied among five selected isolates. © 2014 The American Society of Photobiology.

  10. Thermo tolerant and ethanol producing saccharomyces cerevisiae mutants using gamma radiation

    International Nuclear Information System (INIS)

    Karima, H.M.; Ismail, A.A.; El-Batal, A.I.

    1997-01-01

    Gene manipulation now plays the main role in fermentation industries. However, throughout ethanol production processes, it appeared the requirements for the selection of higher-producing isolate(s) associated, at the same time, with heat-resistant to overcome higher degrees above 30-35 degree, a step which, actually, will reduce final - producing costs. A total of 43 yeast isolates were selected, after exposure of the strain saccharomyces cervisiae to different doses of gamma radiation. Isolated varied in colony size from the original strain as well as among themselves. These isolates were screened for their ability to grow on glucose and supplemented cane molasses media at 30 degree and 40 degree. Out fo them, only 13 isolates proved to grow well on 40 degree. Furthermore, determination of ethanol production by each of these mutants revealed that yielded in general, 16 to 52.0% increase in alcohol production at 40 degree on cane molasses medium (17.5% w/v initial sugars), compared to the original strain. At 40 degree, maximum ethanol yield was 0.63 coupled with 9.5% ethanol concentration and 85.1% sugar conversion which represents 40, 46.2 and 3.4% increase, respectively from the parental strain

  11. HRTEM Study of Oxide Nanoparticles in K3-ODS Ferritic Steel Developed for Radiation Tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Hsiung, L; Fluss, M; Tumey, S; Kuntz, J; El-Dasher, B; Wall, M; Choi, W; Kimura, A; Willaime, F; Serruys, Y

    2009-11-02

    Crystal and interfacial structures of oxide nanoparticles and radiation damage in 16Cr-4.5Al-0.3Ti-2W-0.37 Y{sub 2}O{sub 3} ODS ferritic steel have been examined using high-resolution transmission electron microscopy (HRTEM) techniques. Oxide nanoparticles with a complex-oxide core and an amorphous shell were frequently observed. The crystal structure of complex-oxide core is identified to be mainly monoclinic Y{sub 4}Al{sub 2}O{sub 9} (YAM) oxide compound. Orientation relationships between the oxide and the matrix are found to be dependent on the particle size. Large particles (> 20 nm) tend to be incoherent and have a spherical shape, whereas small particles (< 10 nm) tend to be coherent or semi-coherent and have a faceted interface. The observations of partially amorphous nanoparticles and multiple crystalline domains formed within a nanoparticle lead us to propose a three-stage mechanism to rationalize the formation of oxide nanoparticles containing core/shell structures in as-fabricated ODS steels. Effects of nanoparticle size and density on cavity formation induced by (Fe{sup 8+} + He{sup +}) dual-beam irradiation are briefly addressed.

  12. Normal tissue tolerance to external beam radiation therapy: Larynx and pharynx

    International Nuclear Information System (INIS)

    Debelleix, C.; Pointreau, Y.; Calais, G.; Pointreau, Y.; Lafond, C.; Denis, F.; Bourhis, J.H.

    2010-01-01

    For head and neck cancers, the radiation dose usually needed to sterilize a macroscopic tumour is at least 70 Gy in conventional fractionation. In the larynx, this dose level enables optimal tumour control while exposing the patient to a limited risk of severe complications. For oropharynx and nasopharynx tumors, it is sometimes possible to limit the dose received by the larynx according to the extent of the primary lesion. Thus, if the tumour constraints permit, the maximum dose to the larynx must be less than 63 to 66 Gy. To reduce the risk of laryngeal edema, it is recommended if possible to limit the mean non-involved larynx dose to 40 to 45 Gy. In the pharynx, literature's data suggested to minimize the volume of the pharyngeal constrictor muscles receiving a dose greater than or equal to 60 Gy. Limiting the volume receiving a dose greater than or equal to 50 Gy reduces the risk of dysphagia. These dose constraints should be tailored to each patient taking into account the extent of the initial primary lesion, the possible addition of chemotherapy or a modified fractionation radiotherapy. (authors)

  13. Ionizing-radiation resistance in the desiccation-tolerant cyanobacterium Chroococcidiopsis

    Science.gov (United States)

    Billi, D.; Friedmann, E. I.; Hofer, K. G.; Caiola, M. G.; Ocampo-Friedmann, R.

    2000-01-01

    The effect of X-ray irradiation on cell survival, induction, and repair of DNA damage was studied by using 10 Chroococcidiopsis strains isolated from desert and hypersaline environments. After exposure to 2.5 kGy, the percentages of survival for the strains ranged from 80 to 35%. In the four most resistant strains, the levels of survival were reduced by 1 or 2 orders of magnitude after irradiation with 5 kGy; viable cells were recovered after exposure to 15 kGy but not after exposure to 20 kGy. The severe DNA damage evident after exposure to 2.5 kGy was repaired within 3 h, and the severe DNA damage evident after exposure to 5 kGy was repaired within 24 h. The increase in trichloroacetic acid-precipitable radioactivity in the culture supernatant after irradiation with 2.5 kGy might have been due to cell lysis and/or an excision process involved in DNA repair. The radiation resistance of Chroococcidiopsis strains may reflect the ability of these cyanobacteria to survive prolonged desiccation through efficient repair of the DNA damage that accumulates during dehydration.

  14. Atomic scale simulations of pyrochlore oxides with a tight-binding variable-charge model: implications for radiation tolerance

    International Nuclear Information System (INIS)

    Sattonnay, G; Tétot, R

    2014-01-01

    Atomistic simulations with new interatomic potentials derived from a tight-binding variable-charge model were performed in order to investigate the lattice properties and the defect formation energies in Gd 2 Ti 2 O 7 and Gd 2 Zr 2 O 7 pyrochlores. The main objective was to determine the role played by the defect stability on the radiation tolerance of these compounds. Calculations show that the titanate has a more covalent character than the zirconate. Moreover, the properties of oxygen Frenkel pairs, cation antisite defects and cation Frenkel pairs were studied. In Gd 2 Ti 2 O 7 the cation antisite defect and the Ti-Frenkel pair are not stable: they evolve towards more stable defect configurations during the atomic relaxation process. This phenomenon is driven by a decrease of the Ti coordination number down to five which leads to a local atomic reorganization and strong structural distortions around the defects. These kinds of atomic rearrangements are not observed around defects in Gd 2 Zr 2 O 7 . Therefore, the defect stability in A 2 B 2 O 7 depends on the ability of B atoms to accommodate high coordination number (higher than six seems impossible for Ti). The accumulation of structural distortions around Ti-defects due to this phenomenon could drive the Gd 2 Ti 2 O 7 amorphization induced by irradiation. (paper)

  15. Analysis of the failures and corrective actions for the LHC cryogenics radiation tolerant electronics and its field instruments

    Energy Technology Data Exchange (ETDEWEB)

    Balle, Christoph; Casas, Juan; Vauthier, Nicolas [CERN, TE Department, 1211 Geneva (Switzerland)

    2014-01-29

    The LHC cryogenic system radiation tolerant electronics and their associated field instruments have been in nominal conditions since before the commissioning of the first LHC beams in September 2008. This system is made of about 15’000 field instruments (thermometers, pressure sensors, liquid helium level gauges, electrical heaters and position switches), 7’500 electronic cards and 853 electronic crates. Since mid-2008 a software tool has been deployed, this allows an operator to report a problem and then lists the corrective actions. The tool is a great help in detecting recurrent problems that may be tackled by a hardware or software consolidation. The corrective actions range from simple resets, exchange of defective equipment, repair of electrical connectors, etc. However a recurrent problem that heals by itself is present on some channels. This type of fault is extremely difficult to diagnose and it appears as a temporary opening of an electrical circuit; its duration can range from a few minutes to several months. This paper presents the main type of problems encountered during the last four years, their evolution over time, the various hardware or software consolidations that have resulted and whether they have had an impact in the availability of the LHC beam.

  16. Radiation-induced in vitro mutagenesis system for salt tolerance and other agronomic characters in sugarcane (Saccharum officinarum L.

    Directory of Open Access Journals (Sweden)

    Ashok A. Nikam

    2015-02-01

    Full Text Available Gamma ray-induced in vitro mutagenesis and selection for salt (NaCl tolerance were investigated in sugarcane (Saccharum officinarum L.. Embryogenic callus cultures were irradiated (10 to 80 Gy and subjected to in vitro selection by exposure of irradiated callus to NaCl (0, 50, 100, 150, 200, and 250 mmol L− 1. Increasing NaCl concentrations resulted in growth reduction and increased membrane damage. Salt-selected callus lines were characterized by the accumulation of proline, glycine betaine, and Na+ and K+ concentration. Higher accumulation of proline and glycine betaine was observed in NaCl stressed callus irradiated at 20 Gy. Na+ concentration increased and K+ concentration decreased with increasing salt level. Irradiated callus showed 50–60% regeneration under NaCl stress, and in vitro-regenerated plants were acclimatized in the greenhouse, with 80–85% survival. A total of 138 irradiated and salt-selected selections were grown to maturity and their agronomic performance was evaluated under normal and saline conditions. Of these, 18 mutant clones were characterized for different agro-morphological characters and some of the mutant clones exhibited improved sugar yield with increased Brix%, number of millable canes, and yield. The result suggest that radiation-induced mutagenesis offers an effective way to enhance genetic variation in sugarcane.

  17. Evaluation of radiation tolerance of FETs used for Astro-E2 hard X-ray detector (HXD-II)

    International Nuclear Information System (INIS)

    Itoh, Takeshi; Niko, Hisako; Kokubun, Motohide; Makishima, Kazuo; Kawaharada, Madoka; Takahashi, Isao; Miyasaka, Hiromasa

    2005-01-01

    We evaluated the radiation tolerance of three types of metal-can MOS Field Effect Transistors (FETs). They are candidates for flight electronics of the Hard X-ray Detector (HXD-II) experiment which is onboard the cosmic X-ray satellite Astro-E2 scheduled for launch in 2005. We irradiated FETs with a Co60γ-ray source under several different experimental conditions, and measured changes in their I-V characteristic curves. After a 10krad irradiation during which the gate voltage is set at 0V, all types showed a decrease in the switching voltage by ∼0.2-0.4V. In addition, the gate conductance increased under some irradiation conditions. These experimental results may be explained in terms of trapped charges and boundary levels in the oxide layer beneath the gate electrode. We have confirmed that at least two types of FETs can be used in our satellite-borne experiment, one as relay-driving FETs and the other in TTL-ECL conversion circuits

  18. Use of radiation and in vitro techniques for development of salt tolerant mutants in sugarcane and potato

    International Nuclear Information System (INIS)

    Saif-Ur-Rasheed, M.; Asad, S.; Zafar, Y.; Waheed, R.A.

    2001-01-01

    Sugarcane and potato are propagated vegetatively and are important crops in Pakistan. Protocols were established to initiate callus and regenerate plants in sugarcane and to multiply potato in- vitro from nodal segments. Cultures of potato and sugarcane were irradiated with 5, 20, 40, and 60 Gy. Increase in radiation dose above 20 Gy reduced regeneration capacity of sugarcane callus. Doses higher than 20 Gy were lethal to micropropagated plants of potato. Culture of irradiated sugarcane callus on media containing salt was tried, but no regeneration was obtained. Variants for tolerance to salinity were selected, and evaluated under saline field conditions at four locations. The study showed that the selected variants of both sugarcane and potato were sensitive to high levels of salinity. Variants tested within the same salinity treatment did not differ significantly from each other in the traits investigated. Only boron uptake in the variants was much higher on saline soil than on the normal soil. Polymorphism was detected among the variants by DNA fingerprinting using randomly amplified polymorphic DNA (RAPD) markers. RAPD analysis showed that most of the variants reverted back to normal type. It is concluded that a large number of variants need be screened to obtain the desired mutants. (author)

  19. Normal tissue tolerance to external beam radiation therapy: Rectum; Dose de tolerance a l'irradiation des tissus sains: le rectum

    Energy Technology Data Exchange (ETDEWEB)

    Blanchard, P. [Departement de radiotherapie, institut Gustave-Roussy, 94 - Villejuif (France); Chapet, O. [Service d' oncologie-radiotherapie, centre hospitalier Lyon-Sud, 69 - Pierre-Benite (France)

    2010-07-15

    Radiation proctitis is among the most frequent radiation-induced toxicities. This is related to the high frequency of pelvic tumours and the key role of radiotherapy in the treatment of these tumours. Late rectal toxicity usually occurs within the first two years after the completion of a radiotherapy course. Rectal bleeding and a rectal syndrome are the main symptoms, and can be associated to fistulas or rectal ulcers. Clinical factors, such as diabetes mellitus, a severe acute radiation toxicity, small rectal volume or radiation hypersensitivity, are associated with late rectal toxicity. Dosimetric factors derived from the analysis of dose-volume histograms can also predict the occurrence of radiation proctitis, and help to adapt the prescribed dose and the ballistic of irradiation. (authors)

  20. Analysis of drought-tolerant sugar beet (Beta vulgaris L.) mutants induced with gamma radiation using SDS-PAGE and ISSR markers.

    Science.gov (United States)

    Sen, Ayse; Alikamanoglu, Sema

    2012-01-01

    Drought is one of the major environmental stresses which greatly affect the plant growth and productivity. In the present study, various doses (0-75Gy) of gamma rays were applied to investigate the effect of radiation on shoot tip explants. It was observed that the regeneration rates and plant fresh weights decreased significantly with an increase in radiation dose. The optimal irradiation doses for mutation induction were determined at 15 and 20Gy. Afterwards, the induction of somatic mutation in sugar beet (Beta vulgaris L.) was investigated by irradiation of shoot tips with 15 and 20Gy gamma rays. Irradiated shoot tips were sub-cultured and M(1)V(1)-M(1)V(3) generations were obtained. Mutants tolerant to drought stress were selected on MS medium, supplemented with 10 and 20gl(-1) PEG6000. Of the M(1)V(3) plantlets, drought-tolerant mutants were selected. Leaf soluble proteins obtained from the control and drought-tolerant mutants were analyzed by SDS-PAGE. A total of 22 protein bands were determined and 2 of them were observed to be drought-tolerant mutants except the control. Polymorphism was also detected among the control and drought-tolerant mutants by DNA fingerprinting using ISSR markers. A total of 106 PCR fragments were amplified with 19 ISSR primers and 91 of them were polymorphic. The dendrograms were separated into two main clusters. First cluster included M8 mutant plant, which was applied 20Gy gamma radiation and regenerated on selective culture media containing 10gl(-1) PEG6000 concentration, and the second cluster was further divided into five sub-clusters. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Analysis of drought-tolerant sugar beet (Beta vulgaris L.) mutants induced with gamma radiation using SDS-PAGE and ISSR markers

    International Nuclear Information System (INIS)

    Sen, Ayse; Alikamanoglu, Sema

    2012-01-01

    Drought is one of the major environmental stresses which greatly affect the plant growth and productivity. In the present study, various doses (0–75 Gy) of gamma rays were applied to investigate the effect of radiation on shoot tip explants. It was observed that the regeneration rates and plant fresh weights decreased significantly with an increase in radiation dose. The optimal irradiation doses for mutation induction were determined at 15 and 20 Gy. Afterwards, the induction of somatic mutation in sugar beet (Beta vulgaris L.) was investigated by irradiation of shoot tips with 15 and 20 Gy gamma rays. Irradiated shoot tips were sub-cultured and M 1 V 1 –M 1 V 3 generations were obtained. Mutants tolerant to drought stress were selected on MS medium, supplemented with 10 and 20 gl −1 PEG6000. Of the M 1 V 3 plantlets, drought-tolerant mutants were selected. Leaf soluble proteins obtained from the control and drought-tolerant mutants were analyzed by SDS-PAGE. A total of 22 protein bands were determined and 2 of them were observed to be drought-tolerant mutants except the control. Polymorphism was also detected among the control and drought-tolerant mutants by DNA fingerprinting using ISSR markers. A total of 106 PCR fragments were amplified with 19 ISSR primers and 91 of them were polymorphic. The dendrograms were separated into two main clusters. First cluster included M8 mutant plant, which was applied 20 Gy gamma radiation and regenerated on selective culture media containing 10 g l −1 PEG6000 concentration, and the second cluster was further divided into five sub-clusters.

  2. Analysis of drought-tolerant sugar beet (Beta vulgaris L.) mutants induced with gamma radiation using SDS-PAGE and ISSR markers

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ayse, E-mail: senayse@istanbul.edu.tr [Istanbul University, Faculty of Science, Department of Biology, 34459 Vezneciler, Istanbul (Turkey); Alikamanoglu, Sema [Istanbul University, Faculty of Science, Department of Biology, 34459 Vezneciler, Istanbul (Turkey)

    2012-10-15

    Drought is one of the major environmental stresses which greatly affect the plant growth and productivity. In the present study, various doses (0-75 Gy) of gamma rays were applied to investigate the effect of radiation on shoot tip explants. It was observed that the regeneration rates and plant fresh weights decreased significantly with an increase in radiation dose. The optimal irradiation doses for mutation induction were determined at 15 and 20 Gy. Afterwards, the induction of somatic mutation in sugar beet (Beta vulgaris L.) was investigated by irradiation of shoot tips with 15 and 20 Gy gamma rays. Irradiated shoot tips were sub-cultured and M{sub 1}V{sub 1}-M{sub 1}V{sub 3} generations were obtained. Mutants tolerant to drought stress were selected on MS medium, supplemented with 10 and 20 gl{sup -1} PEG6000. Of the M{sub 1}V{sub 3} plantlets, drought-tolerant mutants were selected. Leaf soluble proteins obtained from the control and drought-tolerant mutants were analyzed by SDS-PAGE. A total of 22 protein bands were determined and 2 of them were observed to be drought-tolerant mutants except the control. Polymorphism was also detected among the control and drought-tolerant mutants by DNA fingerprinting using ISSR markers. A total of 106 PCR fragments were amplified with 19 ISSR primers and 91 of them were polymorphic. The dendrograms were separated into two main clusters. First cluster included M8 mutant plant, which was applied 20 Gy gamma radiation and regenerated on selective culture media containing 10 g l{sup -1} PEG6000 concentration, and the second cluster was further divided into five sub-clusters.

  3. Complete genome sequence of Arthrobacter alpinus ERGS4:06, a yellow pigmented bacterium tolerant to cold and radiations isolated from Sikkim Himalaya.

    Science.gov (United States)

    Kumar, Rakshak; Singh, Dharam; Swarnkar, Mohit Kumar; Singh, Anil Kumar; Kumar, Sanjay

    2016-02-20

    Arthrobacter alpinus ERGS4:06, a yellow pigmented bacterium which exhibited tolerance to cold and UV radiations was isolated from the glacial stream of East Rathong glacier in Sikkim Himalaya. Here we report the 4.3Mb complete genome assembly that has provided the basis for potential role of pigments as a survival strategy to combat stressed environment of cold and high UV-radiation and additionally the ability to produce cold active industrial enzymes. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Epidermal transmittance and phenolic composition in leaves of atrazine-tolerant and atrazine-sensitive cultivars of Brassica napus grown under enhanced UV-B radiation

    International Nuclear Information System (INIS)

    Olsson, L.C.; Veit, M.; Bornman, J.F.

    1999-01-01

    Experiments were conducted on the atrazine-tolerant mutant Stallion and the atrazine-sensitive cv. Paroll of Brassica napus L., which were grown under either visible light or with the addition of UV-B radiation (280–320 nm) for 15 days. The mutant has been shown to be sensitive to high levels of visible light as compared to the atrazine-sensitive cultivar and therefore we wished to determine plant response to UV-B radiation with respect to potential pigment changes, certain anatomical features, radiation penetration and partial photosynthesis. With regard to pigment changes, we were particularly interested in whether the compositional shift in flavonol pigments under enhanced UV-B radiation, previously suggested to favour increased antioxidant activity, is confined to the adaxial epidermis, which generally receives most UV-B radiation or whether the pigment shift is also inducible in the abaxial epidermis.As was to be expected, the penetration of UV-B radiation (310 nm) was lower in the UV-B-exposed plants, which was correlated with an increased amount of UV-screening pigments in the adaxial and abaxial epidermal layers. The main flavonoid glycosides showed the largest shift from kaempferol to quercetin as aglycone moiety in the adaxial epidermal layer. However, in the abaxial epidermal layer the hydroxycinnamic acid (HCA) derivatives and kaempferol glycosides were predominant. Penetration of 430 nm light was higher after UV-B exposure, and probably contributed to the fact that photosynthetic efficiency of photosystem II was unchanged or higher after UV-B exposure. UV-B radiation decreased leaf area in the atrazine-tolerant mutant only. Both cultivars showed an increased leaf thickness after UV-B exposure due to cell elongation mainly of the palisade tissue. This was especially evident in the mutant

  5. Radiation Tolerant Embedded Memory

    National Research Council Canada - National Science Library

    Smith, Brian

    2003-01-01

    ... event effects, and will scale to smaller geometries to provide the same performance. we then designed arrays of that memory to build up blocks to be used in complex Cool-RAD(tm) parts such as microprocessors and digital signal processors.

  6. Tolerance of the High Energy X-ray Imaging Technology ASIC to potentially destructive radiation processes in Earth-orbit-equivalent environments

    Science.gov (United States)

    Ryan, D. F.; Baumgartner, W. H.; Wilson, M.; Benmoussa, A.; Campola, M.; Christe, S. D.; Gissot, S.; Jones, L.; Newport, J.; Prydderch, M.; Richards, S.; Seller, P.; Shih, A. Y.; Thomas, S.

    2018-02-01

    The High Energy X-ray Imaging Technology (HEXITEC) ASIC is designed on a 0.35 μm CMOS process to read out CdTe or CZT detectors and hence provide fine-pixellated spectroscopic imaging in the range 2-200 keV. In this paper, we examine the tolerance of HEXITEC to both potentially destructive cumulative and single event radiation effects. Bare ASICs are irradiated with X-rays up to a total ionising dose (TID) of 1 Mrad (SiO2) and bombarded with heavy ions with linear energy transfer (LET) up to 88.3 MeV mg-1 cm-2. HEXITEC is shown to operate reliably below a TID of 150 krad, have immunity to fatal single event latchup (SEL) and have high tolerance to non-fatal SEL up to LETs of at least 88.3 MeV mg-1 cm-2. The results are compared to predictions of TID and SELs for various Earth-orbits and aluminium shielding thicknesses. It is found that HEXITEC's radiation tolerance to both potentially destructive cumulative and single event effects is sufficient to reliably operate in these environments with moderate shielding.

  7. Mechanisms of tolerance in murine radiation bone marrow chimeras. II. Absence of nonspecific suppression in mature chimeras

    International Nuclear Information System (INIS)

    Auchincloss, H. Jr.; Sachs, D.H.

    1983-01-01

    Spleen cells from a series of allogeneic bone marrow chimeras were sensitized in vitro with stimulator cells from major histocompatibility complex recombinant strains of mice. The combinations were chosen such that both tolerated (host or donor) and nontolerated (third-party) antigens were present on the same stimulator cells in order to determine whether the tolerated host antigens might elicit nonspecific suppressor mechanisms affecting the cell-mediated lympholysis (CML) response to the nontolerated antigens. No evidence for such nonspecific suppression was obtained in several types of assays. Therefore, if suppressor mechanisms exist that mediate such tolerance in mature allogeneic chimeras then these mechanisms must be highly antigen-specific

  8. Radiation tolerance of the pig kidney: a model for determining overall time and fraction factors for preserving renal function

    International Nuclear Information System (INIS)

    Hopewell, J.W.

    1975-01-01

    The Ellis Nominal Standard Dose system has attracted clinical interest for estimating irregular treatment schedules in radiotherapy. This study attempts to examine the system applied to renal tolerance in swine by looking for some regular relationship between time, dose, and fractionation. Also examined was renal function up to two years after treatment. These data indicate that renal tolerance may not be predictable by any simple mathematical expression

  9. Mechanisms of tolerance in murine radiation bone marrow chimeras. I. Nonspecific suppression of alloreactivity by spleen cells from early, but not late, chimeras

    International Nuclear Information System (INIS)

    Auchincloss, H. Jr.; Sachs, D.H.

    1983-01-01

    Allogeneic chimeras were prepared using lethally irradiated B6 hosts and untreated marrow from exsanguinated BALB/c donors. For about two months after reconstitution, chimeras had very weak antihost cell-mediated lymphocytotoxicity (CML) reactivity and little third-party alloreactivity. During this time a cell population capable of suppressing CML reactivity against both host and third-party alloantigens (i.e., antigen-nonspecific) was demonstrated in chimera spleens by in vitro mixing experiments. The putative suppressor cells were Thy-1-negative and radiation-sensitive. Subsequently, mature chimeras showed host tolerance and strong third-party alloreactivity. At this point suppressor mechanisms could no longer be demonstrated. These data are consistent with a clonal elimination hypothesis in that they do not provide evidence to indicate that maintenance of specific immune tolerance is mediated by an active suppressor mechanism

  10. Normal tissue tolerance to external beam radiation therapy: Spinal cord; Tolerance a l'irradiation des tissus sains: moelle epiniere

    Energy Technology Data Exchange (ETDEWEB)

    Habrand, J.L. [Departement de radiotherapie, institut Gustave-Roussy, 94 - Villejuif (France); Centre de protontherapie, institut Curie, 91 - Orsay (France); Drouet, F. [Departement de radiotherapie, centre Rene-Gauducheau, 44 - Nantes (France)

    2010-07-15

    Radiation myelopathy is one of the most dreadful complications of radiation therapy. Despite multiple animal experiments and human autopsic series, its pathogenesis remains largely unknown. In most instances, the classical aspect of myelomalacia combines glial and vascular injuries in various sequences. Recent studies point out the role of oligo-dendrocytes and their precursors, as well as of intercellular mediators (cytokines and stress molecules). The clinical presentation comprises a spectrum of non specific neurological symptoms whose evolution is sometimes regressive but more commonly progressive and life-threatening. Usually, it occurs following a latent period of six months to two years after irradiation of the cervical, thoracic or upper lumbar spine to a dose in excess of 50 Gy, conventionally fractionated. Nonetheless, these typical features can be altered by extrinsic factors, such as hypo fractionation/acceleration of the dose, multiple surgical procedures, chemotherapy especially mega therapy, or neurotoxic drugs. Conversely, hyperfractionated regimens that take into account protracted half-time repair of sublethal damages to the CNS, as well as sophisticated estimates of the dose to the cord and QA programs during the treatment course minimize such risks. (authors)

  11. Normal tissue tolerance to external beam radiation therapy: Testicles; Dose de tolerance a l'irradiation des tissus sain: les testicules

    Energy Technology Data Exchange (ETDEWEB)

    Champetier, C.; Gross, E.; Zaccariotto, A.; Duberge, T.; Guerder, C. [Service de radiotherapie, hopital de la Timone, 13 - Marseille (France); Pointreau, Y. [Pole Henry-S.-Kaplan, CHU Bretonneau, 37 - Tours (France); Ortholan, C. [Centre Antoine-Lacassagne, 06 - Nice (France); Chauvet, B. [Institut Sainte-Catherine, 84 - Avignon (France)

    2010-07-15

    Although there is very little evidence for direct irradiation of the testes, they may receive significant doses, especially in the treatment of pelvic tumors in adults and in pediatrics. The exocrine function of the testis seems to be more sensitive to radiotherapy. There is a risk of sterility, even after low doses of radiation. In the adult or the child who has reached puberty, we should propose a self-preservation of semen prior to radiotherapy. In pre-pubescent children, the problem is more delicate. In all cases, it is necessary to limit the dose to the testicles without affecting the coverage of tumour volume. Patients and/or their care-givers should be systematically informed of the risk of infertility related to irradiation. (authors)

  12. FF-EMU: a radiation tolerant ASIC for the distribution of timing, trigger and control signals in the CMS End-Cap Muon detector

    International Nuclear Information System (INIS)

    Campagnari, C; Costantino, N; Magazzù, G; Tongiani, Claudio

    2012-01-01

    A radiation tolerant integrated circuit for the distribution of clock, trigger and control signals in the Front-End electronics of the CMS End-Cap Muon detector has been developed in the IBM CMOS 130nm technology. The circuit houses transmitter and receiver interfaces to serial links implementing the FF-LYNX protocol that allows the integrated transmission of triggers and data frames with different latency constraints. Encoder and decoder modules associate signal transitions to FF-LYNX frames. The system and the ASIC architecture and behavior and the results of test and characterization of the ASIC prototypes will be presented.

  13. In vitro mutants identification of banana (Musa sp.) with tolerance to toxin from Fusarium oxysporum f. sp cubense, treating buds with several gamma radiation doses

    International Nuclear Information System (INIS)

    Moura, Adriana Muniz Mendes de; Houllou-Kido, Laureen Michelle; Franca, Jose Geraldo Eugenio de; Colaco, Waldeciro

    1999-01-01

    Mutants of banana, obtained through treatment with different level of gamma-radiation (0; 10; 20; 30; 40 Gy), were initially cultivated in vitro in medium for rapid clonal propagation during 30 days. These treatment affected the shoot tips development ratio. Some plants developed necrosis and died, but some of the shoot tips emitted new gems. These material were cultivated in medium 20% of the toxin of Fusarium oxysporum cubense. During the selection period, the necrosis occurrence and death of susceptible shoot tips were observed. Whereas the tolerant shoot tips kept themselves green during the entire selection process. At the end of the selection process, eight shoot tips were obtained. (author)

  14. Conducted and radiated emission tests for fault tolerant power distribution system ECPS-100 developed for PHWR700MW C and I

    International Nuclear Information System (INIS)

    Das, Shantanu; Yadav, Ramnayan

    2016-01-01

    Electronics devices when designed to meet specific requirements, the designers do not generally envisage the amount of electromagnetic interference that this particular device may give as power line conducted noise and radiated noise. After the product is developed, the quantification of the same is carried out in certified EMI-EMC set-up to get these figures of conducted emissions (CE) and radiated emissions (RE), and its mitigation as per limits of the chosen standard. In the latest TM embodiment of Fault Tolerant Power Distribution System ECPS"T"M (Electronics Corporation Power Supply) developed for NPCIL (PHWR700MW plant) we carried out CE and RE tests and quantified the spectrum obtained for CE and RE, and mitigated them as per CISPR22 standards. In this short article we bring out the CE and RE results of the latest product ECPS, done at EMI-EMC Centre of ECIL Hyderabad. (author)

  15. Normal tissue tolerance to external beam radiation therapy: Larynx and pharynx; Dose de tolerance a l'irradiation des tissus sains: larynx et pharynx

    Energy Technology Data Exchange (ETDEWEB)

    Debelleix, C. [Service de radiotherapie, centre hospitalier Dax-Cote d' Argent, 40 - Dax (France); Service de radiotherapie, hopital Saint-Andre, CHU de Bordeaux, 33 - Bordeaux (France); Pointreau, Y.; Calais, G. [Service de radiotherapie, centre regional universitaire de cancerologie Henry-S.-Kaplan, hopital Bretonneau, CHU de Tours, 37 - Tours (France); Universite Francois-Rabelais, 37 - Tours (France); Pointreau, Y. [CNRS, UMR 6239 Genetique, immunotherapie, chimie et cancer, 37 - Tours (France); Laboratoire de pharmacologie-toxicologie, CHRU de Tours, 37 - Tours (France); Lafond, C.; Denis, F. [Centre Jean-Bernard, clinique Victor-Hugo, 72 - Le Mans (France); Bourhis, J.H. [Institut Gustave-Roussy, 94 - Villejuif (France)

    2010-07-15

    For head and neck cancers, the radiation dose usually needed to sterilize a macroscopic tumour is at least 70 Gy in conventional fractionation. In the larynx, this dose level enables optimal tumour control while exposing the patient to a limited risk of severe complications. For oropharynx and nasopharynx tumors, it is sometimes possible to limit the dose received by the larynx according to the extent of the primary lesion. Thus, if the tumour constraints permit, the maximum dose to the larynx must be less than 63 to 66 Gy. To reduce the risk of laryngeal edema, it is recommended if possible to limit the mean non-involved larynx dose to 40 to 45 Gy. In the pharynx, literature's data suggested to minimize the volume of the pharyngeal constrictor muscles receiving a dose greater than or equal to 60 Gy. Limiting the volume receiving a dose greater than or equal to 50 Gy reduces the risk of dysphagia. These dose constraints should be tailored to each patient taking into account the extent of the initial primary lesion, the possible addition of chemotherapy or a modified fractionation radiotherapy. (authors)

  16. Radiation-hardened MRAM-based LUT for non-volatile FPGA soft error mitigation with multi-node upset tolerance

    Science.gov (United States)

    Zand, Ramtin; DeMara, Ronald F.

    2017-12-01

    In this paper, we have developed a radiation-hardened non-volatile lookup table (LUT) circuit utilizing spin Hall effect (SHE)-magnetic random access memory (MRAM) devices. The design is motivated by modeling the effect of radiation particles striking hybrid complementary metal oxide semiconductor/spin based circuits, and the resistive behavior of SHE-MRAM devices via established and precise physics equations. The models developed are leveraged in the SPICE circuit simulator to verify the functionality of the proposed design. The proposed hardening technique is based on using feedback transistors, as well as increasing the radiation capacity of the sensitive nodes. Simulation results show that our proposed LUT circuit can achieve multiple node upset (MNU) tolerance with more than 38% and 60% power-delay product improvement as well as 26% and 50% reduction in device count compared to the previous energy-efficient radiation-hardened LUT designs. Finally, we have performed a process variation analysis showing that the MNU immunity of our proposed circuit is realized at the cost of increased susceptibility to transistor and MRAM variations compared to an unprotected LUT design.

  17. Multicenter Evaluation of the Tolerability of Combined Treatment With PD-1 and CTLA-4 Immune Checkpoint Inhibitors and Palliative Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Andrew [Department of Radiation Oncology, Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Division of Radiation Oncology, University of Ottawa, Ottawa, Ontario (Canada); Wilhite, Tyler J. [Harvard Medical School, Boston, Massachusetts (United States); Pike, Luke R.G. [Harvard Radiation Oncology Program, Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Cagney, Daniel N.; Aizer, Ayal A.; Taylor, Allison; Spektor, Alexander; Krishnan, Monica [Department of Radiation Oncology, Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Ott, Patrick A. [Department of Medical Oncology and Center for Immuno-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Balboni, Tracy A. [Department of Radiation Oncology, Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Hodi, F. Stephen [Department of Medical Oncology and Center for Immuno-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Schoenfeld, Jonathan D., E-mail: jdschoenfeld@partners.org [Department of Radiation Oncology, Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States)

    2017-06-01

    Purpose: To analyze immune-related adverse events (ir-AEs) in patients treated with radiation and immune checkpoint blockade. Methods and Materials: We retrospectively reviewed records from patients with metastatic non-small cell lung cancer, melanoma, or renal cell cancer who received at least 1 cycle of a CTLA-4 or PD-1 inhibitor and radiation. Immune-related adverse events, defined using Common Terminology Criteria for Adverse Events version 4.0, were tabulated in relation to treatment variables, and associations with sequencing and timing were assessed. Results: We identified 133 patients, of whom 28 received a CTLA-4 inhibitor alone, 88 received a PD-1 inhibitor alone, and 17 received both classes of inhibitors either sequentially (n=13) or concurrently (n=4). Fifty-six patients received radiation within 14 days of an immune checkpoint inhibitor. Forty-six patients experienced at least 1 ir-AE (34.6%). Patients receiving both CTLA-4 and PD-1 inhibitors experienced more any-grade ir-AEs as compared with either individually (71% vs 29%, P=.0008). Any-grade ir-AEs occurred in 39% of patients in whom radiation was administered within 14 days of immunotherapy, compared with 23% of other patients (P=.06) and more often in patients who received higher equivalent dose in 2-Gy fractions (EQD2) EQD2 (P=.01). However, most toxicities were mild. There were no associations between site irradiated and specific ir-AEs. Conclusions: Our data suggest the combination of focal palliative radiation and CTLA-4 and/or PD-1 inhibitors is well tolerated, with manageable ir-AEs that did not seem to be associated with the particular site irradiated. Although conclusions are limited by the heterogeneity of patients and treatments, and future confirmatory studies are needed, this information can help guide clinical practice for patients receiving immune checkpoint therapy who require palliative radiation therapy.

  18. Temporal Lobe Reactions After Carbon Ion Radiation Therapy: Comparison of Relative Biological Effectiveness–Weighted Tolerance Doses Predicted by Local Effect Models I and IV

    Energy Technology Data Exchange (ETDEWEB)

    Gillmann, Clarissa, E-mail: clarissa.gillmann@med.uni-heidelberg.de [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Jäkel, Oliver [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Heidelberg Ion Beam Therapy Center (HIT), Heidelberg (Germany); Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany); Schlampp, Ingmar [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Karger, Christian P. [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2014-04-01

    Purpose: To compare the relative biological effectiveness (RBE)–weighted tolerance doses for temporal lobe reactions after carbon ion radiation therapy using 2 different versions of the local effect model (LEM I vs LEM IV) for the same patient collective under identical conditions. Methods and Materials: In a previous study, 59 patients were investigated, of whom 10 experienced temporal lobe reactions (TLR) after carbon ion radiation therapy for low-grade skull-base chordoma and chondrosarcoma at Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt, Germany in 2002 and 2003. TLR were detected as visible contrast enhancements on T1-weighted MRI images within a median follow-up time of 2.5 years. Although the derived RBE-weighted temporal lobe doses were based on the clinically applied LEM I, we have now recalculated the RBE-weighted dose distributions using LEM IV and derived dose-response curves with Dmax,V-1 cm³ (the RBE-weighted maximum dose in the remaining temporal lobe volume, excluding the volume of 1 cm³ with the highest dose) as an independent dosimetric variable. The resulting RBE-weighted tolerance doses were compared with those of the previous study to assess the clinical impact of LEM IV relative to LEM I. Results: The dose-response curve of LEM IV is shifted toward higher values compared to that of LEM I. The RBE-weighted tolerance dose for a 5% complication probability (TD{sub 5}) increases from 68.8 ± 3.3 to 78.3 ± 4.3 Gy (RBE) for LEM IV as compared to LEM I. Conclusions: LEM IV predicts a clinically significant increase of the RBE-weighted tolerance doses for the temporal lobe as compared to the currently applied LEM I. The limited available photon data do not allow a final conclusion as to whether RBE predictions of LEM I or LEM IV better fit better clinical experience in photon therapy. The decision about a future clinical application of LEM IV therefore requires additional analysis of temporal lobe reactions in a

  19. Efficacy and tolerability of concurrent weekly low dose cisplatin during radiation treatment of localised muscle invasive bladder transitional cell carcinoma: A report of two sequential Phase II studies from the Trans Tasman Radiation Oncology Group

    International Nuclear Information System (INIS)

    Gogna, Nirdosh Kumar; Matthews, John H.L.; Turner, Sandra L.; Mameghan, Heidi; Duchesne, Gillian M.; Spry, Nigel; Berry, Martin P.; Keller, Jacqui; Tripcony, Lee

    2006-01-01

    Background and purpose: To determine the feasibility, toxicity, and clinical effectiveness of concurrent weekly cisplatin chemotherapy in conjunction with definitive radiation in the treatment of localised muscle invasive bladder cancer. Patients and methods: In January 1997 the Trans Tasman Radiation Oncology Group embarked on a Phase II study (TROG 97.01) of weekly cisplatin (35 mg/m 2 x 7 doses) plus radiation to a dose of 63 Gy over 7 weeks. Following an interim toxicity analysis, the dose intensity of cisplatin was reduced to 6 cycles and the radiation schedule changed to 64 Gy over 6.5 weeks leading to the second study (TROG 99.06). A total of 113 patients were enrolled. Results: Acute grade 3 urinary toxicity occurred in 23% of the patients. Acute grade 4 pelvic toxicity was not seen. Thirty-eight patients (33%) experienced grade 3 or 4 cisplatin related toxicities with 15 patients (12%) requiring significant dose modification. The reduced dose intensity in Study 99.06 improved tolerability. Incidence of significant late morbidity was low (6%). Seventy-nine patients (70%) achieved complete remission at the 6 month cystoscopic assessment. Local invasive recurrence was seen in 11 of the 79 patients (14%). In 18 patients (16%) isolated superficial TCC/CIS were detected (6 months and beyond).The local control rate was 45% with a functional bladder being retained in 69 of the 113 patients (61%). RFS and DSS at 5 years were 33% and 50%, respectively. Conclusion: Our two sequential Phase II studies have shown that concurrent chemoradiation using weekly cisplatin in the management of localised invasive bladder TCC is feasible and reasonably well tolerated. This approach is currently being investigated further in a randomised study

  20. Multi-gigabit low-power radiation-tolerant data links and improved data motion in trackers

    International Nuclear Information System (INIS)

    Miller, M; Brewer, F; Wang, D; Magazzu, G

    2014-01-01

    We present a set of links based on data-transmission IP in 130nm designed for rapid integration into ASIC designs. These links are designed for use in very high radiation environments as occur in high energy physics experiments. The designs are additionally low power and small area, easing integration with other electronic systems. These links are well suited to use in tracking detectors. Trackers, due to their close proximity to the collision, are subject to very high levels of radiation, and hence require such radiation hardened electronics. The portfolio of radiation hardened data transmission blocks consists of a 1Gbps serializer/deserializer with a very low power consumption ∼ 1mW for each. A differential transmitter and differential receiver rated at 3GHz, both designed to be much faster than needed, as insurance against radiation damage. Finally, the impact of a prototype low-latency, low-power ( < 60mW total link power) 5Gbps link is considered. Case analysis of the impacts of using lower powered, higher speed blocks in hypothetical trackers is studied, showing power improvements relative to alternative technologies

  1. How does solar ultraviolet-B radiation improve drought tolerance of silver birch (Betula pendula Roth.) seedlings?

    Science.gov (United States)

    Robson, T Matthew; Hartikainen, Saara M; Aphalo, Pedro J

    2015-05-01

    We hypothesized that solar ultraviolet (UV) radiation would protect silver birch seedlings from the detrimental effects of water stress through a coordinated suite of trait responses, including morphological acclimation, improved control of water loss through gas exchange and hydraulic sufficiency. To better understand how this synergetic interaction works, plants were grown in an experiment under nine treatment combinations attenuating ultraviolet-A and ultraviolet-B (UVB) from solar radiation together with differential watering to create water-deficit conditions. In seedlings under water deficit, UV attenuation reduced height growth, leaf production and leaf length compared with seedlings receiving the full spectrum of solar radiation, whereas the growth and morphology of well-watered seedlings was largely unaffected by UV attenuation. There was an interactive effect of the treatment combination on water relations, which was more apparent as a change in the water potential at which leaves wilted or plants died than through differences in gas exchange. This suggests that changes occur in the cell wall elastic modulus or accumulation of osmolites in cells under UVB. Overall, the strong negative effects of water deficit are partially ameliorated by solar UV radiation, whereas well-watered silver birch seedlings are slightly disadvantaged by the solar UV radiation they receive. © 2014 John Wiley & Sons Ltd.

  2. An investigation of the combined effects of radiation and cytotoxic drugs on the tolerance of the central nervous system

    International Nuclear Information System (INIS)

    Morris, A.D.

    1983-01-01

    The effects of combined treatment with radiation and methotrexate have been evaluated in the brain and spinal cord of the rat. In the brain, changes in the cell population of the subependymal plate region were used as a quantitative measure of damage after treatment with methotrexate, radiation (single or split-dose exposure) and combination-treatment. In all cases, the cell types most severely affected were those believed to represent the stem-cell population of the subependymal plate. This led to a complex re-distribution of the other cell types within the subependymal plate region. Reduction in the stem-cell population was accompanied by a decline in the mitotic count. It was not possible to conclude whether methotrexate had an additive or a dose-modifying action on the radiation response of subependymal plate cells. (author)

  3. Proposal for the award of a contract, without competitive tendering, for the supply of radiation-tolerant anti-fuse FPGAs for the LHC

    CERN Document Server

    2004-01-01

    This document concerns the award of a contract, without competitive tendering, for the supply of 14 800 radiation-tolerant anti-fuse Field Programmable Gate Arrays (FPGAs) for the LHC. For the reasons explained in this document, the Finance Committee is invited to agree to the negotiation of a contract with MEMEC (CH), for the supply of 14 800 anti-fuse FPGAs for a total amount of 574 330 US dollars (654 900 Swiss francs), not subject to revision, with an option for up to 2960 additional anti-fuse FPGAs for an amount not exceeding 114 866 US dollars (130 980 Swiss francs) bringing the total amount to 689 196 US dollars (758 880 Swiss francs) not subject to revision. The amounts in Swiss francs have been calculated using the present rate of exchange.

  4. Indexes of carbohydrate exchange (CE) and results of toleration test to glucose after effect of low dose of ionizing radiation in late periods

    International Nuclear Information System (INIS)

    Akhmetov, E.A.

    1997-01-01

    The indexes of tolerance test to glucose and values of generalized criterion (GC) being information index of CE system status were determined for 100 liquidators of Chernobyl accident with purpose of study of carbohydrate exchange (CE) status. Analysis of these mean values was carried out according to participation data in liquidation works, exposition duration, rate of radioactive contamination of zone, absorbed dose of external irradiation and age of examined persons. Contribution of each studied components of radiation factor on CE status is estimated. It is determined that both the absorbed dose and the exposition duration are main factors influencing on CE. In examined group there were 32 men with disorders of CE , 20 of them (GC=18.33±0.48) were placed to group of higher risk, 9 men have high tolerance of organism to glucose (GC=32.84±1.37) and 3 men have diabetes of II type (GC=68.6±2.16). Frequency of cases of liquidators' of Chernobyl accident CE disorders allows to made conclusion that ills have dis-function of endocrine section of pancreas

  5. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  6. Optic nerve tolerance to single and fractionated radiation simulating radiosurgery: a rabbit model using visual evoked potentials, fundoscopy and histology

    International Nuclear Information System (INIS)

    Bastin, Kenneth; Mehta, Minesh

    1997-01-01

    Purpose/Objective: To develop a rabbit model enabling single or fractionated optic nerve irradiation, measure post-irradiation visual evoked potentials (VEP), fundoscopic and histopathologic changes, and relate different radiation dosing fractions to these measurable physiologic changes. Materials and Methods: Forty male New Zealand white rabbits underwent surgical right orbital prolapse with template-guided optic nerve irradiation using an iridium-192 high dose rate afterloader. Rabbits were randomized into single fraction groups (0 (control), 10, 12.5, 15, 20, and 30 Gy (3 per group); or two fraction groups of 0 (control) 5, 7.5, 10, 15, and 20 Gy (3 per group); or three fractions groups of 10 and 15 Gy (2 per group). Bilateral fundoscopy and pattern-reversal VEPs (0.5 and 1 c/deg, 1 hertz) were performed at 6 and 12 months (mos) following scheduled irradiation. VEP peaks (P1) were measured. Sacrifice and necropsy followed 12 month evaluation, allowing for histological changes. Results: Excluding deaths from anesthesia (2), CNS mite infection (2), sepsis, pyothorax, 'undetermined' and technically non-analyzable VEP recordings, 24 complete rabbit data sets were evaluated. Fundoscopy demonstrated no gross changes at any dose. Histopathology demonstrated generalized optic nerve atrophy without radiation dose correlation. Among single fraction groups, VEP showed a 6 mos post-irradiation P1 prolongation only in the 20 and 30 Gy groups (maximum 67%). At 12 mos lower dose single fraction groups had a prolonged P1 peak. All fractionated groups above 5 Gy x 2 had P1 prolongation times at 6 mos (maximum 46% in the 15 Gy x 3 data set) but by 12 mos these groups had non-measurable, deteriorated VEPs. Correlating VEP P1 latency with the calculated linear quadratic formula (LQM) biologically equivalent dose (BED,α/β=3) for each group demonstrated a general correlation (t-Test P<.001) as shown: Conclusion: Using a rabbit model for selective optic nerve irradiation we conclude

  7. Effect of Mg$^{2+}$ ions co-doping on timing performance and radiation tolerance of Cerium doped Gd$_{3}$Al$_{2}$Ga$_{3}$O$_{12}$ crystals

    CERN Document Server

    Lucchini, M.T.; Bohacek, P.; Gundacker, S.; Kamada, K.; Nikl, M.; Petrosyan, A.; Yoshikawa, A.; Auffray, E.

    2016-01-01

    Inorganic scintillators with high density and high light yield are of major interest for applications in medical imaging and high energy physics detectors. In this work, the optical and scintillation properties of Mg co-doped Ce:Gd3Al2Ga3O12 crystals, grown using Czochralski technique, have been investigated and compared with Ce:Gd3Al2Ga3O12 ones prepared with identical technology. Improvements in the timing performance of the Mg co-doped samples with respect to Ce:Gd3Al2Ga3O12 ones have been measured, namely a substantial shortening of the rise time and scintillation decay components and lower afterglow were achieved. In particular, a significantly better coincidence time resolution of 233 ps FWHM, being a fundamental parameter for TOF-PET devices, has been observed in Mg co-doped crystals. The samples have also shown a good radiation tolerance under high doses of γ-rays, making them suitable candidates for applications in harsh radiation environments, such as detectors at future collider experiments.

  8. Effect of Mg"2"+ ions co-doping on timing performance and radiation tolerance of Cerium doped Gd_3Al_2Ga_3O_1_2 crystals

    International Nuclear Information System (INIS)

    Lucchini, M.T.; Babin, V.; Bohacek, P.; Gundacker, S.; Kamada, K.; Nikl, M.; Petrosyan, A.; Yoshikawa, A.; Auffray, E.

    2016-01-01

    Inorganic scintillators with high density and high light yield are of major interest for applications in medical imaging and high energy physics detectors. In this work, the optical and scintillation properties of Mg co-doped Ce:Gd_3Al_2Ga_3O_1_2 crystals, grown using Czochralski technique, have been investigated and compared with Ce:Gd_3Al_2Ga_3O_1_2 ones prepared with identical technology. Improvements in the timing performance of the Mg co-doped samples with respect to Ce:Gd_3Al_2Ga_3O_1_2 ones have been measured, namely a substantial shortening of the rise time and scintillation decay components and lower afterglow were achieved. In particular, a significantly better coincidence time resolution of 233 ps FWHM, being a fundamental parameter for TOF-PET devices, has been observed in Mg co-doped crystals. The samples have also shown a good radiation tolerance under high doses of γ-rays, making them suitable candidates for applications in harsh radiation environments, such as detectors at future collider experiments.

  9. Space-Based FPGA Radio Receiver Design, Debug, and Development of a Radiation-Tolerant Computing System

    Directory of Open Access Journals (Sweden)

    Zachary K. Baker

    2010-01-01

    Full Text Available Los Alamos has recently completed the latest in a series of Reconfigurable Software Radios, which incorporates several key innovations in both hardware design and algorithms. Due to our focus on satellite applications, each design must extract the best size, weight, and power performance possible from the ensemble of Commodity Off-the-Shelf (COTS parts available at the time of design. A large component of our work lies in determining if a given part will survive in space and how it will fail under various space radiation conditions. Using two Xilinx Virtex 4 FPGAs, we have achieved 1 TeraOps/second signal processing on a 1920 Megabit/second datastream. This processing capability enables very advanced algorithms such as our wideband RF compression scheme to operate at the source, allowing bandwidth-constrained applications to deliver previously unattainable performance. This paper will discuss the design of the payload, making electronics survivable in the radiation of space, and techniques for debug.

  10. Effects of T cell depletion in radiation bone marrow chimeras. II. Requirement for allogeneic T cells in the reconstituting bone marrow inoculum for subsequent resistance to breaking of tolerance

    International Nuclear Information System (INIS)

    Sykes, M.; Sheard, M.A.; Sachs, D.H.

    1988-01-01

    The ability of normal recipient-type lymphocytes to break tolerance in long-term allogenic radiation chimeras has been investigated. Reconstitution of lethally irradiated mice with a mixture of syngeneic and allogeneic T cell-depleted (TCD) bone marrow (BM) has previously been shown to lead to mixed chimerism and permanent, specific tolerance to donor and host alloantigen (3-5). If allogeneic T cells are not depleted from the reconstituting inoculum, complete allogeneic chimerism results; however, no clinical evidence for GVHD is observed, presumably due to the protective effect provided by syngeneic TCD BM. This model has now been used to study the effects of allogenic T cells administered in reconstituting BM inocula on stability of long-term tolerance. We have attempted to break tolerance in long-term chimeras originally reconstituted with TCD or non-TCD BM by challenging them with inocula containing normal, nontolerant recipient strain lymphocytes. tolerance was broken with remarkable ease in recipients of mixed marrow inocula in which both original BM components were TCD. In contrast, tolerance in chimeras originally reconstituted with non-TCD allogeneic BM was not affected by such inocula. Susceptibility to loss of chimerism and tolerance was not related to initial levels of chimerism per se, but rather to T cell depletion of allogeneic BM, since chimeras reconstituted with TCD allogeneic BM alone (mean level of allogeneic chimerism 98%) were as susceptible as mixed chimeras to the tolerance-breaking effects of such inocula. The possible contribution of GVH reactivity to this resistance was investigated using an F1 into parent strain combination. In these animals, the use of non-TCD F1 BM inocula for reconstitution did not lead to resistance to the tolerance-breaking effects of recipient strain splenocytes

  11. Radiation tolerance of the cervical spinal cord: incidence and dose-volume relationship of symptomatic and asymptomatic late effects following high dose irradiation of paraspinal tumors

    International Nuclear Information System (INIS)

    Liu, Mitchell C.C.; Munzenrider, John E.; Finkelstein, Dianne; Liebsch, Norbert; Adams, Judy; Hug, Eugen B.

    1997-01-01

    changes was between 2 and 8.5 months after radiation therapy. Two risk factors appeared to have significant impact when all incidences were considered: proton portion of tumor dose > 55 CGE (p=.023), and spinal cord surface dose ≥ 60 CGE (p=.045). For patients receiving 55 CGE to >1.5cc of spinal cord, the risk of developing imaging changes was significantly higher (p=.0074). Age < 40 years was found to be correlated with higher incidence of Lhermitt's syndrome (p=.002). No variable was significant for predicting incidence of sensory or motor deficits. Conclusions: For chordomas and chondrosarcomas of the cervical spine, requiring high radiation doses, the guidelines of limiting maximum spinal cord surface dose to ≤ 64 CGE and maximum spinal cord center dose to ≤ 53 CGE appears safe. For the patients who had been treated within the above tolerance dose, none of them had developed motor deficits. Both a significant dose response relationship as well as volume effect for symptomatic or asymptomatic spinal cord changes were observed. The incidence of 1 patient, who developed motor damage after higher radiation doses to the spinal cord than generally allowed, emphasizes the importance of strict guidelines for critical, normal tissues in high dose, conformal radiation treatment

  12. Radiation tolerance studies using fault injection on the Readout Control FPGA design of the ALICE TPC detector

    Science.gov (United States)

    Alme, J.; Fehlker, D.; Lippmann, C.; Mager, M.; Rehman, A. U.; Røed, K.; Röhrich, D.; Ullaland, K.

    2013-01-01

    Single Event Upsets (SEUs) are a major concern for the TPC Readout Control Unit (RCU) of the ALICE experiment. A SEU is defined as a radiation related bit-flip in a memory cell, and a SEU in the onboard SRAM based FPGA of the RCU may lead to corrupted data or, even worse, a system malfunction. The latter situation will affect the operation of the ALICE detector since it causes a premature end of data taking. Active partial reconfiguration is utilized in a dedicated reconfiguration solution on the RCU, and this makes it possible to implement fault injection. Fault injection means inserting bit flips in the configuration memory of the FPGA in a controlled laboratory environment. This paper presents the results of the fault injection study and shows how this result can be combined with SEU measurements to estimate the functional failure rate as a function of luminosity.

  13. SU-E-J-258: Inter- and Intra-Fraction Setup Stability and Couch Change Tolerance for Image Guided Radiation Therapy

    International Nuclear Information System (INIS)

    Teboh, Forbang R; Agee, M; Rowe, L; Creasy, T; Schultz, J; Bell, R; Wong, J; Armour, E

    2014-01-01

    Purpose: Immobilization devices combine rigid patient fixation as well as comfort and play a key role providing the stability required for accurate radiation delivery. In the setup step, couch re-positioning needed to align the patient is derived via registration of acquired versus reference image. For subsequent fractions, replicating the initial setup should yield identical alignment errors when compared to the reference. This is not always the case and further couch re-positioning can be needed. An important quality assurance measure is to set couch tolerances beyond which additional investigations are needed. The purpose of this work was to study the inter-fraction couch changes needed to re-align the patient and the intra-fraction stability of the alignment as a guide to establish the couch tolerances. Methods: Data from twelve patients treated on the Accuray CyberKnife (CK) system for fractionated intracranial radiotherapy and immobilized with Aquaplast RT, U-frame, F-Head-Support (Qfix, PA, USA) was used. Each fraction involved image acquisitions and registration with the reference to re-align the patient. The absolute couch position corresponding to the approved setup alignment was recorded per fraction. Intra-fraction set-up corrections were recorded throughout the treatment. Results: The average approved setup alignment was 0.03±0.28mm, 0.15±0.22mm, 0.06±0.31mm in the L/R, A/P, S/I directions respectively and 0.00±0.35degrees, 0.03±0.32degrees, 0.08±0.45degrees for roll, pitch and yaw respectively. The inter-fraction reproducibility of the couch position was 6.65mm, 10.55mm, and 4.77mm in the L/R, A/P and S/I directions respectively and 0.82degrees, 0.71degrees for roll and pitch respectively. Intra-fraction monitoring showed small average errors of 0.21±0.21mm, 0.00±0.08mm, 0.23±0.22mm in the L/R, A/P, S/I directions respectively and 0.03±0.12degrees, 0.04±0.25degrees, and 0.13±0.15degrees in the roll, pitch and yaw respectively. Conclusion

  14. SU-E-J-258: Inter- and Intra-Fraction Setup Stability and Couch Change Tolerance for Image Guided Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Teboh, Forbang R; Agee, M; Rowe, L; Creasy, T; Schultz, J; Bell, R; Wong, J; Armour, E [Johns Hopkins University, Baltimore, MD (United States)

    2014-06-01

    Purpose: Immobilization devices combine rigid patient fixation as well as comfort and play a key role providing the stability required for accurate radiation delivery. In the setup step, couch re-positioning needed to align the patient is derived via registration of acquired versus reference image. For subsequent fractions, replicating the initial setup should yield identical alignment errors when compared to the reference. This is not always the case and further couch re-positioning can be needed. An important quality assurance measure is to set couch tolerances beyond which additional investigations are needed. The purpose of this work was to study the inter-fraction couch changes needed to re-align the patient and the intra-fraction stability of the alignment as a guide to establish the couch tolerances. Methods: Data from twelve patients treated on the Accuray CyberKnife (CK) system for fractionated intracranial radiotherapy and immobilized with Aquaplast RT, U-frame, F-Head-Support (Qfix, PA, USA) was used. Each fraction involved image acquisitions and registration with the reference to re-align the patient. The absolute couch position corresponding to the approved setup alignment was recorded per fraction. Intra-fraction set-up corrections were recorded throughout the treatment. Results: The average approved setup alignment was 0.03±0.28mm, 0.15±0.22mm, 0.06±0.31mm in the L/R, A/P, S/I directions respectively and 0.00±0.35degrees, 0.03±0.32degrees, 0.08±0.45degrees for roll, pitch and yaw respectively. The inter-fraction reproducibility of the couch position was 6.65mm, 10.55mm, and 4.77mm in the L/R, A/P and S/I directions respectively and 0.82degrees, 0.71degrees for roll and pitch respectively. Intra-fraction monitoring showed small average errors of 0.21±0.21mm, 0.00±0.08mm, 0.23±0.22mm in the L/R, A/P, S/I directions respectively and 0.03±0.12degrees, 0.04±0.25degrees, and 0.13±0.15degrees in the roll, pitch and yaw respectively. Conclusion

  15. Brachial plexus dose tolerance in head and neck cancer patients treated with sequential intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Thomas, Tarita O; Refaat, Tamer; Choi, Mehee; Bacchus, Ian; Sachdev, Sean; Rademaker, Alfred W; Sathiaseelan, Vythialingam; Karagianis, Achilles; Mittal, Bharat B

    2015-01-01

    We aimed to study the radiation induced brachial plexopathy in patients with head and neck squamous cell carcinoma (HNSCC) treated with Sequential Intensity Modulated Radiation Therapy (S-IMRT). This IRB approved study included 68 patients with HNSCC treated consecutively. Detailed dose volume histogram data was generated for ipsilateral and contralateral brachial plexus (BP) volumes receiving a specified dose (Vds) i.e. V50-V75 and dose in Gray covering specified percent of BP volume (Dvs) i.e. D5-D30 and maximum point doses (Dmax). To assess BP injury all patients’ charts were reviewed in detail for sign and symptoms of BP damage. Post-hoc comparisons were done using Tukey-Kramer method to account for multiple significance testing. The mean and maximum doses to BP were significantly different (p < .05) based on tumor site, nodal status and tumor stage. The mean volume to the ipsilateral BP for V50, V60, V70, and V75 were 7.01 cc, 4.37 cc, 1.47 cc and 0.24 cc, respectively. The mean dose delivered to ≤5% of ipsilateral BP was 68.70 Gy (median 69.5Gy). None of the patients had acute or late brachial plexopathy or any other significant neurological complications, with a minimum follow up of two years (mean 54 months). In this study cohort, at a minimum of two-years follow up, the mean dose of 68.7Gy, a median dose to 69.5Gy to ≤5% of ipsilateral BP, and a median Dmax of 72.96Gy did not result in BP injury when patients were treated with S-IMRT technique. However, longer follow up is needed

  16. Quantitative in vivo assessment of radiation injury of the liver using Gd-EOB-DTPA enhanced MRI: tolerance dose of small liver volumes

    Directory of Open Access Journals (Sweden)

    Pech Maciej

    2011-04-01

    Full Text Available Abstract Backround Hepatic radiation toxicity restricts irradiation of liver malignancies. Better knowledge of hepatic tolerance dose is favourable to gain higher safety and to optimize radiation regimes in radiotherapy of the liver. In this study we sought to determine the hepatic tolerance dose to small volume single fraction high dose rate irradiation. Materials and methods 23 liver metastases were treated by CT-guided interstitial brachytherapy. MRI was performed 3 days, 6, 12 and 24 weeks after therapy. MR-sequences were conducted with T1-w GRE enhanced by hepatocyte-targeted Gd-EOB-DTPA. All MRI data sets were merged with 3D-dosimetry data. The reviewer indicated the border of hypointensity on T1-w images (loss of hepatocyte function or hyperintensity on T2-w images (edema. Based on the volume data, a dose-volume-histogram was calculated. We estimated the threshold dose for edema or function loss as the D90, i.e. the dose achieved in at least 90% of the pseudolesion volume. Results At six weeks post brachytherapy, the hepatocyte function loss reached its maximum extending to the former 9.4Gy isosurface in median (i.e., ≥9.4Gy dose exposure led to hepatocyte dysfunction. After 12 and 24 weeks, the dysfunctional volume had decreased significantly to a median of 11.4Gy and 14Gy isosurface, respectively, as a result of repair mechanisms. Development of edema was maximal at six weeks post brachytherapy (9.2Gy isosurface in median, and regeneration led to a decrease of the isosurface to a median of 11.3Gy between 6 and 12 weeks. The dose exposure leading to hepatocyte dysfunction was not significantly different from the dose provoking edema. Conclusion Hepatic injury peaked 6 weeks after small volume irradiation. Ongoing repair was observed up to 6 months. Individual dose sensitivity may differ as demonstrated by a relatively high standard deviation of threshold values in our own as well as all other published data.

  17. Reirradiation of Prostate Cancer Local Failures After Previous Curative Radiation Therapy: Long-Term Outcome and Tolerance

    International Nuclear Information System (INIS)

    Zilli, Thomas; Benz, Eileen; Dipasquale, Giovanna; Rouzaud, Michel; Miralbell, Raymond

    2016-01-01

    Purpose: To evaluate the safety, feasibility, side-effect profile, and proof of concept of external beam radiation therapy (EBRT) with or without a brachytherapy (BT) boost for salvage of exclusive local failure after primary EBRT for prostate cancer. Methods and Materials: Fourteen patients with presumed exclusive local recurrence after primary EBRT with or without BT were considered eligible for reirradiation. The median normalized total dose in 2-Gy fractions (NTD_2_G_y, α/β ratio = 1.5 Gy) was 74 Gy (range, 66-98.4 Gy) at first irradiation. Median time between the first irradiation and the reirradiation was 6.1 years (range, 4.7-10.2 years). Results: Between 2003 and 2008 salvage treatment was delivered with a median NTD_2_G_y of 85.1 Gy (range, 70-93.4) to the prostate with EBRT with (n=10) or without (n=4) BT. Androgen deprivation was given to 12 patients (median time of 12 months). No grade ≥3 toxicity was observed during and within 6 weeks after RT. After a median follow-up of 94 months (range, 48-172 months) after salvage RT, 5-year grade ≥3 genitourinary and gastrointestinal toxicity-free survival figures were 77.9% ± 11.3% and 57.1% ± 13.2%, respectively. Four patients presented with combined grade 4 genitourinary/gastrointestinal toxicity. The 5-year biochemical relapse-free, local relapse-free, distant metastasis-free, and cancer-specific survival rates were 35.7% ± 12.8%, 50.0% ± 13.4%, 85.7% ± 9.4%, and 100%, respectively. Conclusion: Salvage whole-gland reirradiation for patients with a suspicion of exclusive local recurrence after initial RT may be associated with a high rate of severe radiation-induced side effects and poor long-term biochemical and local control.

  18. Effects of ultraviolet-B radiation on fish: Histologic comparison of a UVB-sensitive and a UVB-tolerant species

    Science.gov (United States)

    Blazer, V.S.; Fabacher, D.L.; Little, E.E.; Ewing, M.S.; Kocan, K.M.

    1997-01-01

    Lahontan cutthroat trout Oncorhynchus clarki henshawi were sensitive to simulated solar ultraviolet-B radiation (UVB) and exhibited grossly visible signs of sunburn upon exposure. Razorback suckers Xyrauchen texanus, however, were tolerant to simulated solar UVB and showed no grossly visible signs of exposure. Cutthroat trout also had considerably less of an unidentified, possibly photoprotective, substance in the skin than did razorback suckers. In all attempt to characterize the cellular response to simulated solar UVB exposure in the skin of these two species, we examined sections from UVB-exposed fish by light and electron microscopy. Cutthroat trout showed grossly visible signs of sunburn by 48 h. Histologic observations included a sloughing of the mucous cells, necrosis and edema in the epidermis and dermis, and, in some cases, secondary fungal infections. Razorback suckers did not show any visible signs of sunburn during 72 h of experimental exposure. Histologic analyses revealed that cell necrosis had occurred, but the severe necrosis and sloughing noted in cutthroat trout was not observed. An increase in epidermal thickness, apparently due to hypertrophy and hyperplasia of large PAS-negative cells, occurred in the razorback suckers. These cells contained a large central region of low electron density and appeared to be club cells. In some, extensive interdigitation of the electron-lucent cytoplasm with adjacent epithelial cell margins occurred. Near the surface of the epidermis these cells were larger and the interface with epithelial cells lacked complex interdigitation. These cells may contain the substance that appears to protect razorback suckers against UV-B radiation.

  19. Weanling piglet cerebellum: a surrogate for tolerance to MRT (microbeam radiation therapy) in pediatric neuro-oncology

    Science.gov (United States)

    Laissue, Jean A.; Blattmann, Hans; Di Michiel, Marco; Slatkin, Daniel N.; Lyubimova, Nadia; Guzman, Raphael; Zimmermann, Werner; Birrer, Stephan; Bley, Tim; Kircher, Patrick; Stettler, Regina; Fatzer, Rosmarie; Jaggy, Andre; Smilowitz, Henry; Brauer, Elke; Bravin, Alberto; Le Duc, Geraldine; Nemoz, Christian; Renier, Michel; Thomlinson, William C.; Stepanek, Jiri; Wagner, Hans-Peter

    2001-12-01

    The cerebellum of the weanling piglet (Yorkshire) was used as a surrogate for the radiosensitive human infant cerebellum in a Swiss-led program of experimental microbeam radiation therapy (MRT) at the ESRF. Five weanlings in a 47 day old litter of seven, and eight weanlings in a 40 day old litter of eleven were irradiated in November, 1999 and June, 2000, respectively. A 1.5 cm-wide x 1.5 xm-high array of equally space approximately equals 20-30 micrometers wide, upright microbeams spaced at 210 micrometers intervals was propagated horizontally, left to right, through the cerebella of the prone, anesthetized piglets. Skin-entrance intra-microbeam peak adsorbed doses were uniform, either 150, 300, 425, or 600 gray (Gy). Peak and inter-microbeam (valley) absorbed doses in the cerebellum were computed with the PSI version of the Monte Carlo code GEANT and benchmarked using Gafchromic and radiochromic film microdosimetry. For approximately equals 66 weeks [first litter; until euthanasia], or approximately equals 57 weeks [second litter; until July 30, 2001] after irradiation, the littermates were developmentally, behaviorally, neurologically and radiologically normal as observed and tested by experienced farmers and veterinary scientists unaware of which piglets were irradiated or sham-irradiated. Morever, MRT implemented at the ESRF with a similar array of microbeams and a uniform skin-entrance peak dose of 625 Gy, followed by immunoprophylaxis, was shown to be palliative or curative in young adult rats bearing intracerebral gliosarcomas. These observations give further credence to MRT's potential as an adjunct therapy for brain tumors in infancy, when seamless therapeutic irradiation of the brain is hazardous.

  20. First Annual Progress Report on Radiation Tolerance of Controlled Fusion Welds in High Temperature Oxidation Resistant FeCrAl Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hu, Xunxiang [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Richard H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-12-01

    The present report summarizes and discusses the first year efforts towards developing a modern, nuclear grade FeCrAl alloy designed to have enhanced radiation tolerance and weldability under the Department of Energy (DOE) Nuclear Energy Enabling Technologies (NEET) program. Significant efforts have been made within the first year of this project including the fabrication of seven candidate FeCrAl alloys with well controlled chemistry and microstructure, the microstructural characterization of these alloys using standardized and advanced techniques, mechanical properties testing and evaluation of base alloys, the completion of welding trials and production of weldments for subsequent testing, the design of novel tensile specimen geometry to increase the number of samples that can be irradiated in a single capsule and also shorten the time of their assessment after irradiation, the development of testing procedures for controlled hydrogen ingress studies, and a detailed mechanical and microstructural assessment of weldments prior to irradiation or hydrogen charging. These efforts and research results have shown promise for the FeCrAl alloy class as a new nuclear grade alloy class.

  1. Performance of new radiation tolerant thin n-in-p Silicon pixel sensors for the CMS experiment at High Luminosity LHC

    CERN Document Server

    Dalla Betta, G.F; Darbo, G; Dinardo, Mauro; Giacomini, G; Menasce, Dario; Meschini, Marco; Messineo, Alberto; Moroni, Luigi; Rivera, Ryan Allen; Ronchin, S; Uplegger, Lorenzo; Viliani, Lorenzo; Zoi, Irene; Zuolo, Davide

    2017-01-01

    The High Luminosity upgrade of the CERN-LHC (HL-LHC) demands for a new high-radiation tolerant solid-state pixel sensor capable of surviving fluencies up to a few 10$^{16}$ particles/cm$^2$ at $\\sim$3 cm from the interaction point. To this extent the INFN ATLAS-CMS joint research activity in collaboration with Fondazione Bruno Kessler-FBK, is aiming at the development of thin n-in-p type pixel sensors for the HL-LHC. The R and D covers both planar and single-sided 3D columnar pixel devices made with the Si-Si Direct Wafer Bonding technique, which allows for the production of sensors with 100~$\\mu {\\rm m}$ and 130~$\\mu {\\rm m}$ active thickness for planars, and 130~$\\mu {\\rm m}$ for 3D sensors, the thinnest ones ever produced so far. First prototypes of hybrid modules bump-bonded to the present CMS readout chip have been tested in beam tests. Preliminary results on their performance before and after irradiation are presented.

  2. Performance of the THS4302 and the Class V Radiation-Tolerant THS4304-SP Silicon Germanium Wideband Amplifiers at Extreme Temperatures

    Science.gov (United States)

    Patterson, Richard L.; Elbuluk, Malik; Hammoud, Ahmad; VanKeuls, Frederick W.

    2009-01-01

    This report discusses the performance of silicon germanium, wideband gain amplifiers under extreme temperatures. The investigated devices include Texas Instruments THS4304-SP and THS4302 amplifiers. Both chips are manufactured using the BiCom3 process based on silicon germanium technology along with silicon-on-insulator (SOI) buried oxide layers. The THS4304-SP device was chosen because it is a Class V radiation-tolerant (150 kRad, TID silicon), voltage-feedback operational amplifier designed for use in high-speed analog signal applications and is very desirable for NASA missions. It operates with a single 5 V power supply [1]. It comes in a 10-pin ceramic flatpack package, and it provides balanced inputs, low offset voltage and offset current, and high common mode rejection ratio. The fixed-gain THS4302 chip, which comes in a 16-pin leadless package, offers high bandwidth, high slew rate, low noise, and low distortion [2]. Such features have made the amplifier useful in a number of applications such as wideband signal processing, wireless transceivers, intermediate frequency (IF) amplifier, analog-to-digital converter (ADC) preamplifier, digital-to-analog converter (DAC) output buffer, measurement instrumentation, and medical and industrial imaging.

  3. ALDO: A radiation-tolerant, low-noise, adjustable low drop-out linear regulator in 0.35 μm CMOS technology

    International Nuclear Information System (INIS)

    Carniti, P.; Cassina, L.; Gotti, C.; Maino, M.; Pessina, G.

    2016-01-01

    In this work we present ALDO, an adjustable low drop-out linear regulator designed in AMS 0.35 μm CMOS technology. It is specifically tailored for use in the upgraded LHCb RICH detector in order to improve the power supply noise for the front end readout chip (CLARO). ALDO is designed with radiation-tolerant solutions such as an all-MOS band-gap voltage reference and layout techniques aiming to make it able to operate in harsh environments like High Energy Physics accelerators. It is capable of driving up to 200 mA while keeping an adequate power supply filtering capability in a very wide frequency range from 10 Hz up to 100 MHz. This property allows us to suppress the noise and high frequency spikes that could be generated by a DC/DC regulator, for example. ALDO also shows a very low noise of 11.6 μV RMS in the same frequency range. Its output is protected with over-current and short detection circuits for a safe integration in tightly packed environments. Design solutions and measurements of the first prototype are presented.

  4. ALDO: A radiation-tolerant, low-noise, adjustable low drop-out linear regulator in 0.35 μm CMOS technology

    Energy Technology Data Exchange (ETDEWEB)

    Carniti, P., E-mail: paolo.carniti@mib.infn.it [INFN, Sezione di Milano Bicocca, I-20126 Milano (Italy); Dipartimento di Fisica, Università di Milano Bicocca, I-20126 Milano (Italy); Cassina, L.; Gotti, C.; Maino, M.; Pessina, G. [INFN, Sezione di Milano Bicocca, I-20126 Milano (Italy); Dipartimento di Fisica, Università di Milano Bicocca, I-20126 Milano (Italy)

    2016-07-11

    In this work we present ALDO, an adjustable low drop-out linear regulator designed in AMS 0.35 μm CMOS technology. It is specifically tailored for use in the upgraded LHCb RICH detector in order to improve the power supply noise for the front end readout chip (CLARO). ALDO is designed with radiation-tolerant solutions such as an all-MOS band-gap voltage reference and layout techniques aiming to make it able to operate in harsh environments like High Energy Physics accelerators. It is capable of driving up to 200 mA while keeping an adequate power supply filtering capability in a very wide frequency range from 10 Hz up to 100 MHz. This property allows us to suppress the noise and high frequency spikes that could be generated by a DC/DC regulator, for example. ALDO also shows a very low noise of 11.6 μV RMS in the same frequency range. Its output is protected with over-current and short detection circuits for a safe integration in tightly packed environments. Design solutions and measurements of the first prototype are presented.

  5. ALDO: A radiation-tolerant, low-noise, adjustable low drop-out linear regulator in 0.35 μm CMOS technology

    Science.gov (United States)

    Carniti, P.; Cassina, L.; Gotti, C.; Maino, M.; Pessina, G.

    2016-07-01

    In this work we present ALDO, an adjustable low drop-out linear regulator designed in AMS 0.35 μm CMOS technology. It is specifically tailored for use in the upgraded LHCb RICH detector in order to improve the power supply noise for the front end readout chip (CLARO). ALDO is designed with radiation-tolerant solutions such as an all-MOS band-gap voltage reference and layout techniques aiming to make it able to operate in harsh environments like High Energy Physics accelerators. It is capable of driving up to 200 mA while keeping an adequate power supply filtering capability in a very wide frequency range from 10 Hz up to 100 MHz. This property allows us to suppress the noise and high frequency spikes that could be generated by a DC/DC regulator, for example. ALDO also shows a very low noise of 11.6 μV RMS in the same frequency range. Its output is protected with over-current and short detection circuits for a safe integration in tightly packed environments. Design solutions and measurements of the first prototype are presented.

  6. Stereotactic Body Radiation Therapy for Locally Advanced and Borderline Resectable Pancreatic Cancer Is Effective and Well Tolerated

    Energy Technology Data Exchange (ETDEWEB)

    Chuong, Michael D. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Springett, Gregory M. [Gastrointestinal Tumor Program, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Freilich, Jessica M.; Park, Catherine K. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Weber, Jill M. [Gastrointestinal Tumor Program, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Mellon, Eric A. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Hodul, Pamela J.; Malafa, Mokenge P.; Meredith, Kenneth L. [Gastrointestinal Tumor Program, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Hoffe, Sarah E. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Shridhar, Ravi, E-mail: ravi.shridhar@moffitt.org [Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, Florida (United States)

    2013-07-01

    Purpose: Stereotactic body radiation therapy (SBRT) provides high rates of local control (LC) and margin-negative (R0) resections for locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC), respectively, with minimal toxicity. Methods and Materials: A single-institution retrospective review was performed for patients with nonmetastatic pancreatic cancer treated with induction chemotherapy followed by SBRT. SBRT was delivered over 5 consecutive fractions using a dose painting technique including 7-10 Gy/fraction to the region of vessel abutment or encasement and 5-6 Gy/fraction to the remainder of the tumor. Restaging scans were performed at 4 weeks, and resectable patients were considered for resection. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Results: Seventy-three patients were evaluated, with a median follow-up time of 10.5 months. Median doses of 35 Gy and 25 Gy were delivered to the region of vessel involvement and the remainder of the tumor, respectively. Thirty-two BRPC patients (56.1%) underwent surgery, with 31 undergoing an R0 resection (96.9%). The median OS, 1-year OS, median PFS, and 1-year PFS for BRPC versus LAPC patients was 16.4 months versus 15 months, 72.2% versus 68.1%, 9.7 versus 9.8 months, and 42.8% versus 41%, respectively (all P>.10). BRPC patients who underwent R0 resection had improved median OS (19.3 vs 12.3 months; P=.03), 1-year OS (84.2% vs 58.3%; P=.03), and 1-year PFS (56.5% vs 25.0%; P<.0001), respectively, compared with all nonsurgical patients. The 1-year LC in nonsurgical patients was 81%. We did not observe acute grade ≥3 toxicity, and late grade ≥3 toxicity was minimal (5.3%). Conclusions: SBRT safely facilitates margin-negative resection in patients with BRPC pancreatic cancer while maintaining a high rate of LC in unresectable patients. These data support the expanded implementation of SBRT for pancreatic cancer.

  7. Crafting tolerance

    DEFF Research Database (Denmark)

    Kirchner, Antje; Freitag, Markus; Rapp, Carolin

    2011-01-01

    Ongoing changes in social structures, orientation, and value systems confront us with the growing necessity to address and understand transforming patterns of tolerance as well as specific aspects, such as social tolerance. Based on hierarchical analyses of the latest World Values Survey (2005......–08) and national statistics for 28 countries, we assess both individual and contextual aspects that influence an individual's perception of different social groupings. Using a social tolerance index that captures personal attitudes toward these groupings, we present an institutional theory of social tolerance. Our...

  8. Radiation tolerant combinational logic cell

    Science.gov (United States)

    Maki, Gary R. (Inventor); Gambles, Jody W. (Inventor); Whitaker, Sterling (Inventor)

    2009-01-01

    A system has a reduced sensitivity to Single Event Upset and/or Single Event Transient(s) compared to traditional logic devices. In a particular embodiment, the system includes an input, a logic block, a bias stage, a state machine, and an output. The logic block is coupled to the input. The logic block is for implementing a logic function, receiving a data set via the input, and generating a result f by applying the data set to the logic function. The bias stage is coupled to the logic block. The bias stage is for receiving the result from the logic block and presenting it to the state machine. The state machine is coupled to the bias stage. The state machine is for receiving, via the bias stage, the result generated by the logic block. The state machine is configured to retain a state value for the system. The state value is typically based on the result generated by the logic block. The output is coupled to the state machine. The output is for providing the value stored by the state machine. Some embodiments of the invention produce dual rail outputs Q and Q'. The logic block typically contains combinational logic and is similar, in size and transistor configuration, to a conventional CMOS combinational logic design. However, only a very small portion of the circuits of these embodiments, is sensitive to Single Event Upset and/or Single Event Transients.

  9. Early Mucosal Reactions During and After Head-and-Neck Radiotherapy: Dependence of Treatment Tolerance on Radiation Dose and Schedule Duration

    International Nuclear Information System (INIS)

    Fenwick, John D.; Lawrence, Geoff P.; Malik, Zafar; Nahum, Alan E.; Mayles, W. Philip M.

    2008-01-01

    Purpose: To more precisely localize the dose-time boundary between head-and-neck radiotherapy schedules inducing tolerable and intolerable early mucosal reactions. Methods and Materials: Total cell-kill biologically effective doses (BED CK ) have been calculated for 84 schedules, including incomplete repair effects, but making no other corrections for the effect of schedule duration T. [BED CK ,T] scatterplots are graphed, overlying BED CKboundary (T) curves on the plots and using discriminant analysis to optimize BED CKboundary (T) to best represent the boundary between the tolerable and intolerable schedules. Results: More overlap than expected is seen between the tolerable and intolerable treatments in the 84-schedule [BED CK ,T] scatterplot, but this was largely eliminated by removing gap and tolerated accelerating schedules from the plot. For the remaining 57 predominantly regular schedules, the BED CKboundary (T) boundary increases with increasing T (p = 0.0001), curving upwards significantly nonlinearly (p = 0.00007) and continuing to curve beyond 15 days (p = 0.035). The regular schedule BED CKboundary (T) boundary does not describe tolerability well for accelerating schedules (p = 0.002), with several tolerated accelerating schedules lying above the boundary where regular schedules would be intolerable. Gap schedule tolerability also is not adequately described by the regular schedule boundary (p = 0.04), although no systematic offset exists between the regular boundary and the overall gap schedule tolerability pattern. Conclusions: All schedules analyzed (regular, gap, and accelerating) with BED CK values below BED CKboundary (T)=69.5x(T/32.2)/sin((T/32.2) (radians) )-3.5Gy 10 (forT≤50 days) are tolerable, and many lying above the boundary are intolerable. The accelerating schedules analyzed were tolerated better overall than are the regular schedules with similar [BED CK ,T] values.

  10. Om tolerance

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2007-01-01

    Begrebet tolerance og dets betydninger diskuteres med henblik på en tydeliggørelse af begrebets forbindelse med stat, religion, ytringsfrihed, skeptisk erkendelsesteori, antropologi og pædagogik.......Begrebet tolerance og dets betydninger diskuteres med henblik på en tydeliggørelse af begrebets forbindelse med stat, religion, ytringsfrihed, skeptisk erkendelsesteori, antropologi og pædagogik....

  11. Radiations

    International Nuclear Information System (INIS)

    Pujol Mora, J.

    1999-01-01

    The exposition to ionizing radiations is a constant fact in the life of the human being and its utilization as diagnostic and therapeutic method is generalized. However, it is notorious how as years go on, the fear to the ionizing radiation seems to persist too, and this fact is not limited to the common individual, but to the technical personnel and professional personnel that labors with them same. (S. Grainger) [es

  12. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  13. Radiation

    International Nuclear Information System (INIS)

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  14. Towards Tolerance

    NARCIS (Netherlands)

    Lisette Kuyper; Jurjen Iedema; Saskia Keuzenkamp

    2013-01-01

    Across Europe, public attitudes towards lesbian, gay and bisexual (LGB) individuals range from broad tolerance to widespread rejection. Attitudes towards homosexuality are more than mere individual opinions, but form part of the social and political structures which foster or hinder the equality

  15. Intolerant tolerance.

    Science.gov (United States)

    Khushf, G

    1994-04-01

    The Hyde Amendment and Roman Catholic attempts to put restrictions on Title X funding have been criticized for being intolerant. However, such criticism fails to appreciate that there are two competing notions of tolerance, one focusing on the limits of state force and accepting pluralism as unavoidable, and the other focusing on the limits of knowledge and advancing pluralism as a good. These two types of tolerance, illustrated in the writings of John Locke and J.S. Mill, each involve an intolerance. In a pluralistic context where the free exercise of religion is respected, John Locke's account of tolerance is preferable. However, it (in a reconstructed form) leads to a minimal state. Positive entitlements to benefits like artificial contraception or nontherapeutic abortions can legitimately be resisted, because an intolerance has already been shown with respect to those that consider the benefit immoral, since their resources have been coopted by taxation to advance an end that is contrary to their own. There is a sliding scale from tolerance (viewed as forbearance) to the affirmation of communal integrity, and this scale maps on to the continuum from negative to positive rights.

  16. Conformal radiation therapy of localized prostate cancer: acute tolerance and early evaluation of effectiveness; Konformierende Strahlentherapie des lokalisierten Prostatakarzinoms: Akute Toleranz und fruehe Wirksamkeit

    Energy Technology Data Exchange (ETDEWEB)

    Zierhut, D. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany); Flentje, M. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany); Sroka-Perez, G. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany); Rudat, V. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany); Engenhart-Cabillic, R. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany); Wannenmacher, M. [Klinische Radiologie, Radiologische Universitaetsklinik Heidelberg (Germany)

    1997-02-01

    Aim: In a prospective trial early effectiveness and acute toxicity of conformal 3D-planned radiotherapy for localized prostate cancer was quantified using dose-volume-histogramms and evaluated with respect of treatment technique. Results: Eleven patients (of 32) had none, 15 mild (RTOG grade 1) and 6 moderate symptoms (RTOG grade 2, mainly diarrhoea, dysuria and polyuria). Acute complications leading to treatment interruption did not occur. In 16 patients symptoms disappeared within 6 weeks after radiotherapy. Only 2 men had symptoms which lasted longer than 3 months and were endoscopically examined. Up to now no late complications were detected. Incidence and severity of toxicity was significantly (p<0,05) related to the size of treatment volume. Akute toxicity was found to depend statistically significant (p<0,05) on the proportional volume of bladder and rectum, irradiated with more than 35 Gy. In 81% of the patients with pretherapeutic elevated PSA levels normalisation of PSA was observed. Overall mean PSA levels of 15.7{+-}22.6 {mu}g/l at the beginning of radiotherapy fell to 2.1{+-}3.7 {mu}g/l 6 weeks after irradiation. Only 1 Patient relapsed locally 22 months after radiation therapy. Conclusion: We conclude that due to modern 3D-planned conformal techniques with optimization of treatment dose and improved protection of critical organs such as urinary bladder and rectum, radiotherapy allows an effective and well tolerated therapy of localized prostatic carcinoma. (orig./VHE) [Deutsch] Ziel: Quantifizierung der fruehen Wirksamkeit und akuten Toxizitaet der 3D-geplanten und konformierenden Strahlentherapie des lokalisierten Prostatakarzinoms mittels Dosis-Volumen-Histogramm sowie Untersuchung der Abhaengigkeit von der Bestrahlungstechnik in einer prospektiven Studie. Ergebnisse: Elf Patienten hatten keine, 15 leichte (RTOG Grad I) und sechs maessiggradige Nebenwirkungen (RTOG Grad II, meist Diarrhoe, Dysurie und Polyurie). Bei keinem Patienten musste die

  17. Salt Tolerance

    OpenAIRE

    Xiong, Liming; Zhu, Jian-Kang

    2002-01-01

    Studying salt stress is an important means to the understanding of plant ion homeostasis and osmo-balance. Salt stress research also benefits agriculture because soil salinity significantly limits plant productivity on agricultural lands. Decades of physiological and molecular studies have generated a large body of literature regarding potential salt tolerance determinants. Recent advances in applying molecular genetic analysis and genomics tools in the model plant Arabidopsis thaliana are sh...

  18. Infectious Tolerance

    OpenAIRE

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, ...

  19. Infectious Tolerance

    Science.gov (United States)

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, freshly isolated CD4+ T helper (Th) cells. This infectious suppressive activity, transferred from CD25+ Treg cells via cell contact, is cell contact–independent and partially mediated by soluble transforming growth factor (TGF)-β. The induction of suppressive properties in conventional CD4+ Th cells represents a mechanism underlying the phenomenon of infectious tolerance. This explains previously published conflicting data on the role of TGF-β in CD25+ Treg cell–induced immunosuppression. PMID:12119350

  20. Integration of Principles of Systems Biology and Radiation Biology: Toward Development of in silico Models to Optimize IUdR-Mediated Radiosensitization of DNA Mismatch Repair Deficient (Damage Tolerant) Human Cancers

    International Nuclear Information System (INIS)

    Kinsella, Timothy J.; Gurkan-Cavusoglu, Evren; Du, Weinan; Loparo, Kenneth A.

    2011-01-01

    Over the last 7 years, we have focused our experimental and computational research efforts on improving our understanding of the biochemical, molecular, and cellular processing of iododeoxyuridine (IUdR) and ionizing radiation (IR) induced DNA base damage by DNA mismatch repair (MMR). These coordinated research efforts, sponsored by the National Cancer Institute Integrative Cancer Biology Program (ICBP), brought together system scientists with expertise in engineering, mathematics, and complex systems theory and translational cancer researchers with expertise in radiation biology. Our overall goal was to begin to develop computational models of IUdR- and/or IR-induced base damage processing by MMR that may provide new clinical strategies to optimize IUdR-mediated radiosensitization in MMR deficient (MMR − ) “damage tolerant” human cancers. Using multiple scales of experimental testing, ranging from purified protein systems to in vitro (cellular) and to in vivo (human tumor xenografts in athymic mice) models, we have begun to integrate and interpolate these experimental data with hybrid stochastic biochemical models of MMR damage processing and probabilistic cell cycle regulation models through a systems biology approach. In this article, we highlight the results and current status of our integration of radiation biology approaches and computational modeling to enhance IUdR-mediated radiosensitization in MMR − damage tolerant cancers.

  1. High lenticular tolerance to ultraviolet radiation-B by pigmented guinea-pig; application of a safety limit strategy for UVR-induced cataract.

    Science.gov (United States)

    Mody, Vino C; Kakar, Manoj; Söderberg, Per G; Löfgren, Stefan

    2012-05-01

    The purpose of this study was to determine a threshold measure, maximum tolerable dose (MTD), for avoidance of UVR-B-induced cataract in the pigmented guinea-pig. Thirty pupil-dilated anesthetized young female guinea-pigs, divided into five equal groups, received between 0 and 84.9 kJ/m(2) unilateral UVR-B. Lens extraction and in vitro lens photography occurred 24 hr after exposure. Measurement of intensity of lens light scattering served as quantifying tool for the degree of cataract. Data analysis included regression, using a second order polynomial model. The applied MTD concept was based on the UVR-B dose-response curve obtained for the pigmented guinea-pig. A smaller number of pigmented guinea-pigs, pigmented rats and albino rats underwent morphometric analysis of the anterior segment geometry. All eyes exposed to UVR-B developed cataract in the anterior subcapsular region. MTD for avoidance of UVR-B-induced cataract was 69.0 kJ/m(2) in the pigmented guinea-pig. Iris was considerably thicker in the guinea-pig than in the rats. Lens blockage by the dilated iris was lowest in the guinea-pig. Maximum tolerable dose for avoidance of UVR-B-induced cataract in the pigmented guinea-pig was 69.0 kJ/m(2), over 10-fold higher than the threshold 5 kJ/m(2) obtained by Pitts et al. in the pigmented rabbit. Maximum tolerable dose is an appropriate method for estimation of toxicity for UVR-B-induced cataract in the guinea-pig. The pigmented guinea-pig is significantly less sensitive to UVR-B exposure than the pigmented rabbit and pigmented rat. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

  2. Acquired immunologic tolerance in chimeras and histocompatibility factors in cattle and their relationship to those in humans. Final report. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Stone, W.H.

    1976-03-01

    During the course of this project we have studied 35 pairs of chimeric cattle twins. It is now clear that fractionated doses of whole-body /sup 60/Co irradiation can cause marked shifts in the proportions of the two erythrocyte populations that make up the chimeric mixture. However, it has not been possible to eliminate one of the two cell types and thus abrogate the acquired immunologic tolerance. The results of our extensive skin-grafting experiments are remarkable because they show that a chimeric twin may mount a sufficient immune response to reject its cotwin's skin while remaining completely tolerant to erythropoietic elements of its cotwin. In conjunction with these studies, we have acquired sufficient data to define a major histocompatibility locus in cattle using alloimmune anti-lymphocyte typing sera as well as the mixed lymphocyte culture technic. This project has also yielded a considerable number of new immunogenetic parameters for cattle, monkeys and birds. Such parameters are useful for basic and applied studies in immunology.

  3. Repressive Tolerance

    DEFF Research Database (Denmark)

    Pedersen, Morten Jarlbæk

    2017-01-01

    Consultation of organised interests and others when drafting laws is often seen as an important source of both input and output legitimacy. But whereas the input side of the equation stems from the very process of listening to societal actors, output legitimacy can only be strengthened if consult......Consultation of organised interests and others when drafting laws is often seen as an important source of both input and output legitimacy. But whereas the input side of the equation stems from the very process of listening to societal actors, output legitimacy can only be strengthened...... a substantial effect on the substance of laws – shows that there is a great difference in the amenability of different branches of government but that, in general, authorities do not listen much despite a very strong consultation institution and tradition. A suggestion for an explanation could be pointing...... to an administrative culture of repressive tolerance of organised interests: authorities listen but only reacts in a very limited sense. This bears in it the risk of jeopardising the knowledge transfer from societal actors to administrative ditto thus harming the consultation institutions’ potential for strengthening...

  4. Biological studies on the tolerance of different developmental stages of the mosquito, Culex Pipiens to gamma radiation through the first five generations

    Energy Technology Data Exchange (ETDEWEB)

    Soliman, I Abul Yazid I

    1993-12-31

    The biological effects of irradiating of the immature stages of Culex Pipiens with chronic doses of gamma radiation in the successive generations were studied. The results obtained a re summarized as follow: A- Egg Irradiation. B- Larval Irradiation. C-Pupal Irradiation. D-Combined effect of irradiation and dimilin on (a) Egg stage. (b) Larval Stage. (c) Pupal Stage. 23 tabs.,19 figs.,86 refs. Thesis (Ms.c)

  5. Implications of mycosporine-like amino acid and antioxidant defenses in UV-B radiation tolerance for the algae species Ptercladiella capillacea and Gelidium amansii.

    Science.gov (United States)

    Lee, Tse-Min; Shiu, Chia-Tai

    2009-02-01

    Ultraviolet-B (UV-B) radiation (0.5, 1.0, 1.5, and 3.0Wm(-2)) induced higher H(2)O(2) production and lipid peroxidation in alga Gelidium amansii inhabiting in lower subtidal regions than upper subtidal alga Ptercladiella capillacea. Compared to G. amansii, mycosporine-like amino acid (MAA) concentration in P. capillacea was higher and can be increased by 0.5-1.0Wm(-2) UV-B, while carotenoid concentration was lower but also increased by 1.5-3.0Wm(-2) UV-B. UV-B increased ascorbate concentration, but to a higher degree in P. capillacea. UV-B decreased glutathione concentration, but to a higher degree in G. amansii. UV-B increased ascorbate peroxidase (APX) and glutathione reductase (GR) activities in P.capillacea but decreased them in G. amansii. UV-B increased superoxide dismutase and catalase activities, but to a higher degree in G. amansii. So, G. amansii suffered greater oxidative stress from UV-B radiation. P. capillacea can effectively reduce UV-B sensitivity by increasing sunscreen ability and antioxidant defense capacity.

  6. Fiducial-free CyberKnife stereotactic body radiation therapy (SBRT) for single vertebral body metastases: acceptable local control and normal tissue tolerance with 5 fraction approach

    Energy Technology Data Exchange (ETDEWEB)

    Gill, Beant; Oermann, Eric; Ju, Andrew; Suy, Simeng; Yu, Xia; Rabin, Jennifer [Department of Radiation Medicine, Georgetown University Hospital,, Washington, DC (United States); Kalhorn, Christopher; Nair, Mani N.; Voyadzis, Jean-Marc [Department of Neurosurgery, Georgetown University Hospital,, Washington, DC (United States); Unger, Keith; Collins, Sean P.; Harter, K. W.; Collins, Brian T., E-mail: collinsb@gunet.georgetown.edu [Department of Radiation Medicine, Georgetown University Hospital,, Washington, DC (United States)

    2012-04-26

    This retrospective analysis examines the local control and toxicity of five-fraction fiducial-free CyberKnife stereotactic body radiation therapy (SBRT) for single vertebral body (VB) metastases. All patients had favorable performance status (ECOG 0–1), oligometastatic disease, and no prior spine irradiation. A prescribed dose of 30–35 Gy was delivered in five fractions to the planning target volume (PTV) using the CyberKnife with X-sight spine tracking. Suggested maximum spinal cord and esophagus point doses were 30 and 40 Gy, respectively. A median 30 Gy (IQR, 30–35 Gy) dose was delivered to a median prescription isodose line of 70% (IQR, 65–77%) to 20 patients. At 34 months median follow-up (IQR, 25–40 months) for surviving patients, the 1- and 2-year Kaplan–Meier local control estimates were 80 and 73%, respectively. Two of the five local failures were infield in patients who had received irradiation to the gross tumor volume and three were paravertebral failures just outside the PTV in patients with prior corpectomy. No local failures occurred in patients who completed VB radiation alone. The 1- and 2-year Kaplan–Meier overall survival estimates were 80 and 57%, respectively. Most deaths were attributed to metastatic disease; one death was attributed to local recurrence. The mean maximum point doses were 26.4 Gy (SD, 5.1 Gy) to the spinal cord and 29.1 Gy (SD, 8.9 Gy) to the esophagus. Patients receiving maximum esophagus point doses greater than 35 Gy experienced acute dysphagia (Grade I/II). No spinal cord toxicity was documented. Five-fraction fiducial-free CyberKnife SBRT is an acceptable treatment option for newly diagnosed VB metastases with promising local control rates and minimal toxicity despite the close proximity of such tumors to the spinal cord and esophagus. A prospective study aimed at further enhancing local control by targeting the intact VB and escalating the total dose is planned.

  7. Charge collection and non-ionizing radiation tolerance of CMOS pixel sensors using a 0.18 μm CMOS process

    Science.gov (United States)

    Zhang, Ying; Zhu, Hongbo; Zhang, Liang; Fu, Min

    2016-09-01

    The proposed Circular Electron Positron Collider (CEPC) will be primarily aimed for precision measurements of the discovered Higgs boson. Its innermost vertex detector, which will play a critical role in heavy-flavor tagging, must be constructed with fine-pitched silicon pixel sensors with low power consumption and fast readout. CMOS pixel sensor (CPS), as one of the most promising candidate technologies, has already demonstrated its excellent performance in several high energy physics experiments. Therefore it has been considered for R&D for the CEPC vertex detector. In this paper, we present the preliminary studies to improve the collected signal charge over the equivalent input capacitance ratio (Q / C), which will be crucial to reduce the analog power consumption. We have performed detailed 3D device simulation and evaluated potential impacts from diode geometry, epitaxial layer properties and non-ionizing radiation damage. We have proposed a new approach to improve the treatment of the boundary conditions in simulation. Along with the TCAD simulation, we have designed the exploratory prototype utilizing the TowerJazz 0.18 μm CMOS imaging sensor process and we will verify the simulation results with future measurements.

  8. Predictors of Rectal Tolerance Observed in a Dose-Escalated Phase 1-2 Trial of Stereotactic Body Radiation Therapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D.W. Nathan [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Cho, L. Chinsoo [Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota (United States); Straka, Christopher [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Christie, Alana [Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Lotan, Yair [Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Pistenmaa, David [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado, Denver, Colorado (United States); Nanda, Akash [Department of Radiation Oncology, University of Florida Health Cancer Center at Orlando Health, Orlando, Florida (United States); Kueplian, Patrick [Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California (United States); Brindle, Jeffrey [Prairie Lakes Hospital, Watertown, South Dakota (United States); Cooley, Susan; Perkins, Alida [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Raben, David [Department of Radiation Oncology, University of Colorado, Denver, Colorado (United States); Xie, Xian-Jin [Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Timmerman, Robert D., E-mail: robert.timmerman@utsouthwestern.edu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)

    2014-07-01

    Purpose: To convey the occurrence of isolated cases of severe rectal toxicity at the highest dose level tested in 5-fraction stereotactic body radiation therapy (SBRT) for localized prostate cancer; and to rationally test potential causal mechanisms to guide future studies and experiments to aid in mitigating or altogether avoiding such severe bowel injury. Methods and Materials: Clinical and treatment planning data were analyzed from 91 patients enrolled from 2006 to 2011 on a dose-escalation (45, 47.5, and 50 Gy in 5 fractions) phase 1/2 clinical study of SBRT for localized prostate cancer. Results: At the highest dose level, 6.6% of patients treated (6 of 91) developed high-grade rectal toxicity, 5 of whom required colostomy. Grade 3+ delayed rectal toxicity was strongly correlated with volume of rectal wall receiving 50 Gy >3 cm{sup 3} (P<.0001), and treatment of >35% circumference of rectal wall to 39 Gy (P=.003). Grade 2+ acute rectal toxicity was significantly correlated with treatment of >50% circumference of rectal wall to 24 Gy (P=.010). Conclusion: Caution is advised when considering high-dose SBRT for treatment of tumors near bowel structures, including prostate cancer. Threshold dose constraints developed from physiologic principles are defined, and if respected can minimize risk of severe rectal toxicity.

  9. Phase II Pilot Study of Bevacizumab in Combination with Temozolomide and Regional Radiation Therapy for Up-Front Treatment of Patients With Newly Diagnosed Glioblastoma Multiforme: Interim Analysis of Safety and Tolerability

    International Nuclear Information System (INIS)

    Lai, Albert; Filka, Emese; McGibbon, Bruce; Nghiemphu, Phioanh Leia; Graham, Carrie; Yong, William H.; Mischel, Paul; Liau, Linda M.; Bergsneider, Marvin; Pope, Whitney; Selch, Michael; Cloughesy, Tim

    2008-01-01

    Purpose: To assess interim safety and tolerability of a 10-patient, Phase II pilot study using bevacizumab (BV) in combination with temozolomide (TMZ) and regional radiation therapy (RT) in the up-front treatment of patients with newly diagnosed glioblastoma. Methods and Materials: All patients received standard external beam regional RT of 60.0 Gy in 30 fractions started within 3 to 5 weeks after surgery. Concurrently TMZ was given daily at 75 mg/m 2 for 42 days during RT, and BV was given every 2 weeks at 10 mg/kg starting with the first day of RT/TMZ. After a 2-week interval upon completion of RT, the post-RT phase commenced with resumption of TMZ at 150 to 200 mg/m 2 for 5 days every 4 weeks and continuation of BV every 2 weeks. Results: For these 10 patients, toxicities were compiled until study discontinuation or up to ∼40 weeks from initial study treatment for those remaining on-study. In terms of serious immediate or delayed neurotoxicity, 1 patient developed presumed radiation-induced optic neuropathy. Among the toxicities that could be potentially treatment related, relatively high incidences of fatigue, myelotoxicity, wound breakdown, and deep venous thrombosis/pulmonary embolism were observed. Conclusion: The observed toxicities were acceptable to continue enrollment toward the overall target group of 70 patients. Preliminary efficacy analysis shows encouraging mean progression-free survival. At this time data are not sufficient to encourage routine off-label use of BV combined with TMZ/RT in the setting of newly diagnosed glioblastoma without longer follow-up, enrollment of additional patients, and thorough efficacy assessment

  10. Development and evaluation of drought tolerant mutant germplasm of cereals and legume

    International Nuclear Information System (INIS)

    Sobieh, S. E. S.

    2000-10-01

    A report on (i) response of some induced gamma ray mutations in sesame for drought tolerance in the newly reclaimed sandy soil and (ii) an attempt to improve bread wheat for water stress tolerance using gamma radiation

  11. Teaching Tolerance? Associational Diversity and Tolerance Formation

    DEFF Research Database (Denmark)

    Rapp, Carolin; Freitag, Markus

    2015-01-01

    , a closer look is taken at how associational diversity relates to the formation of tolerance and the importance of associations as schools of tolerance are evaluated. The main theoretical argument follows contact theory, wherein regular and enduring contact in diverse settings reduces prejudice and thereby...

  12. Radiated Emissions Test Approach

    Science.gov (United States)

    2015-10-02

    1. Draft Department of Transportation (DOT) Test Plan to Develop : Interference Tolerance Masks for GNSS Receivers in the L1 : Radiofrequency Band (1559 1610 MHz) provides high level : overview of radiated emissions test setup : 2. Presenta...

  13. Radiation myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Howell, D A [Derbyshire Royal Infirmary, Derby (UK)

    1979-10-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed.

  14. Radiation myelopathy

    International Nuclear Information System (INIS)

    Howell, D.A.

    1979-01-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed. (UK)

  15. NEW RADIATION RESISTANT GREASES

    Energy Technology Data Exchange (ETDEWEB)

    DasGupta, Sharda; Slobodian, J. T.

    1962-11-20

    New radiation resistant greases were prepared from commercially available greases by carrying out radioinduced reactions with styrene. The radiation tolerances of the products were 250-1000 fold more than the starting materials and any product of similar properties now available. The various properties of the new products initially and after exposure to large radiation doses were in no case inferior to the original greases and in some respects improvements were observed. Radiation tolerance of commercial greases could be enhanced by the addition of polystyrene to form a physical mixture rather than copolymers. The reaction mechanisms involved at all stages were studied using infrared spectroscopic techniques. (P.C.H.)

  16. Human tolerance to space flight

    Science.gov (United States)

    Huntoon, C. L.

    1989-01-01

    Medical studies of astronauts and cosmonauts before, during, and after space missions have identified several effects of weightlessness and other factors that influence the ability of humans to tolerate space flight. Weightlessness effects include space motion sickness, cardiovascular abnormalities, reduction in immune system function, loss of red blood cells, loss of bone mass, and muscle atrophy. Extravehicular activity (EVA) increases the likelihood that decompression sickness may occur. Radiation also gives reason for concern about health of crewmembers, and psychological factors are important on long-term flights. Countermeasures that have been used include sensory preadaptation, prebreathing and use of various air mixtures for EVA, loading with water and electrolytes, exercise, use of pharmacological agents and special diets, and psychological support. It appears that humans can tolerate and recover satisfactorily from at least one year of space flight, but a number of conditions must be further ameliorated before long-duration missions can be considered routine.

  17. Lactose tolerance tests

    Science.gov (United States)

    Hydrogen breath test for lactose tolerance ... Two common methods include: Lactose tolerance blood test Hydrogen breath test The hydrogen breath test is the preferred method. It measures the amount of hydrogen ...

  18. Radiation effects in semiconductors

    CERN Document Server

    2011-01-01

    There is a need to understand and combat potential radiation damage problems in semiconductor devices and circuits. Written by international experts, this book explains the effects of radiation on semiconductor devices, radiation detectors, and electronic devices and components. These contributors explore emerging applications, detector technologies, circuit design techniques, new materials, and innovative system approaches. The text focuses on how the technology is being used rather than the mathematical foundations behind it. It covers CMOS radiation-tolerant circuit implementations, CMOS pr

  19. Recognition and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms...... or interpretations of recognition and toleration are considered, confusing and problematic uses of the terms are noted, and the compatibility of toleration and recognition is discussed. The article argues that there is a range of legitimate and importantly different conceptions of both toleration and recognition...

  20. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out...... that there is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...... of the nominal feedback con-troller....

  1. Radiation retinopathy

    International Nuclear Information System (INIS)

    Wara, W.M.; Irvine, A.R.; Neger, R.E.; Howes, E.L. Jr.; Phillips, T.L.

    1979-01-01

    The records were reviewed of all patients treated with irradiation to the eye at the University of California, San Francisco, between 1960 and 1975. Eight patients were identified who had developed radiation retinopathy 1 to 3 years postrirradiation. Lesions included retinal vascular occlusions, hemorrhages, microaneurysms, exudates, neovascularization, vitreous hemorrhage, retinal detachments, and optic atrophy with blindness. Four patients had received less than 5000 rad in 6 weeks to the retina, a dose usually considered within normal tissue tolerance

  2. Mechanical tolerance stackup and analysis

    CERN Document Server

    Fischer, Bryan R

    2004-01-01

    BackgroundDimensioning and TolerancingTolerance Format and Decimal PlacesConverting Plus/Minus Dimensions and Tolerances into Equal Bilaterally Toleranced DimensionsVariation and Sources of VariationTolerance AnalysisWorst-case Tolerance StackupsStatistical Tolerance StackupsGeometric Dimensioning and Tolerancing (GD&T)Converting Plus/Minus Tolerancing to Positional Tolerancing and Projected Tolerance ZonesDiametral and Radial Tolerance StackupsSpecifying Material Condition Modifiers and Their Effect on Tolerance Stackups The Tolerance Stackup SketchThe Tolerance Stackup Report FormTolerance S

  3. Final Report: Energetics of Radiation Tolerant Nanoceramics

    International Nuclear Information System (INIS)

    Castro, Ricardo

    2016-01-01

    The report describes in details the achievements of the project addressing the performance of nanomaterials in radioactive environments. The project addresses the fundamentals of the role of interface features on the defect dynamics during irradiation and present models to predict behavior based on thermodynamic properties. Papers and products, including formation of students in this strategic area, are presented in details as well.

  4. High speed radiation tolerant data links

    Energy Technology Data Exchange (ETDEWEB)

    Brewer, Forrest [Univ. of California, Santa Barbara, CA (United States); Incandela, Joseph [Univ. of California, Santa Barbara, CA (United States)

    2016-04-01

    This project was slated to design and develop Rad-Hard IP components for 1Gb/s links and supporting hardware designs such as PLL, SER/DES, pad drivers and receivers and custom protocol hardware for the 1Gb/s channel. Also included in the proposal was a study of a hardened memory to be used as a packet buffer for channel and data concentrator components to meet the 1 Gb/s specification. Over the course of the proposal, technology change and innovation of hardware designs lead us away from the 1 Gb/s goal to contemplate much higher performance link IP which, we believed better met the goals of physics experiments. Note that CERN microelectronics had managed to create a 4.7 Gb/s link designed to drive optical fibers and containing infrastructure for connecting much lower bandwidth front-end devices. Our own work to that point had shown the possibility of constructing a link with much lower power, lower physical overhead but of equivalent performance that could be designed to integrate directly onto the front-end ASIC (ADC and data encoding) designs. Substantial overall power savings and experimental simplicity could be achieved by eliminating data transmission to data concentrators and data concentrators and related hardened buffering themselves, with conversion to optical media at a removed distance from the experiment core. We had already developed and tested Rad-Hard SER/DES components (1Gb in 130nm standard cells) and redundant Pad Drivers/Receivers (3+ Gb/s designed and measured performance), and had a viable 1Gb/s link design based on redundant a stuttered clock receiver and classical PLL, so the basic goals of the proposal had been achieved. Below, in chronological order, are the products and tools we constructed, as well as our tests and publications.

  5. Final Report: Energetics of Radiation Tolerant Nanoceramics

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Ricardo [Univ. of California, Davis, CA (United States)

    2016-12-20

    The report describes in details the achievements of the project addressing the performance of nanomaterials in radioactive environments. The project addresses the fundamentals of the role of interface features on the defect dynamics during irradiation and present models to predict behavior based on thermodynamic properties. Papers and products, including formation of students in this strategic area, are presented in details as well.

  6. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2013-01-01

    Under conditions of pluralism different cultures, interests or values can come into conflict, which raises the problem of how to secure peaceful co-existence. The idea of toleration historically emerged as an answer to this problem. Recently Rainer Forst has argued that toleration should not just...... be based on a modus vivendi designed to secure peaceful co-existence, but should be based on moral reasons. Forst therefore advances what he calls the ‘respect conception’ of toleration as an in itself morally desirable type of relationship, which is furthermore the only conception of toleration...... that avoids various so-called ‘paradoxes of toleration’. The paper first examines whether Forst’s respect conception can be applied descriptively to distinguish between actual patterns of behaviour and classify different acts of toleration. Then the focus is shifted to toleration out of respect as a normative...

  7. Tolerance in Drosophila

    OpenAIRE

    Atkinson, Nigel S.

    2009-01-01

    The set of genes that underlie ethanol tolerance (inducible resistance) are likely to overlap with the set of genes responsible for ethanol addiction. Whereas addiction is difficult to recognize in simple model systems, behavioral tolerance is readily identifiable and can be induced in large populations of animals. Thus, tolerance lends itself to analysis in model systems with powerful genetics. Drosophila melanogaster has been used by a variety of laboratories for the identification of genes...

  8. Compromise and Toleration

    DEFF Research Database (Denmark)

    Rostbøll, Christian F.

    Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature, justifi...... in compromise are more stringent than those for being tolerated. Still, the limits of compromise cannot be drawn to narrowly if it is to remain its value as a form of agreement that respects and embodies the differences of opinion in society.......Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature......, justification, and limits of compromise if we see it merely as a matter of toleration. While toleration is mainly a matter of accepting citizens' equal right to co-existence as subjects to law, political compromise includes the parties in making law – it makes them co-authors of law. Toleration entails...

  9. Tolerances in micro manufacturing

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Zhang, Yang; Islam, Aminul

    This paper describes a method for analysis of tolerances in micro manufacturing. It proposes a mapping oftolerances to dimensions and compares this with current available international standards. The analysisdocuments that tolerances are not scaled down as the absolute dimension. In practice...

  10. Fault tolerant computing systems

    International Nuclear Information System (INIS)

    Randell, B.

    1981-01-01

    Fault tolerance involves the provision of strategies for error detection damage assessment, fault treatment and error recovery. A survey is given of the different sorts of strategies used in highly reliable computing systems, together with an outline of recent research on the problems of providing fault tolerance in parallel and distributed computing systems. (orig.)

  11. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    be based on a modus vivendi designed to secure peaceful co-existence, but should be based on moral reasons. Forst therefore advances what he calls the ‘respect conception’ of toleration as an in itself morally desirable type of relationship, which is furthermore the only conception of toleration...

  12. Recognition and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms or inter...

  13. Remember Tolerance Differently

    DEFF Research Database (Denmark)

    Tønder, Lars

    2012-01-01

    This essay questions the linear conception of history which often accompanies the way contemporary democratic theory tends to disavow tolerance's discontinuities and remainders. In the spirit of Foucault's genealogy of descent, the idea is to develop a new sense of tolerance's history, not by inv......This essay questions the linear conception of history which often accompanies the way contemporary democratic theory tends to disavow tolerance's discontinuities and remainders. In the spirit of Foucault's genealogy of descent, the idea is to develop a new sense of tolerance's history......, not by invoking a critique external to contemporary democratic theory, but by witnessing the history of tolerance paraliptically, with an eye to what it obscures and yet presupposes....

  14. Effect of Mg.sup.2+./sup. ions co-doping on timing performance and radiation tolerance of Cerium doped Gd.sub.3./sub.Al.sub.2./sub.Ga.sub.3./sub.O.sub.12./sub. crystals

    Czech Academy of Sciences Publication Activity Database

    Lucchini, M.T.; Babin, Vladimir; Boháček, Pavel; Gundacker, S.; Kamada, K.; Nikl, Martin; Petrosyan, A.; Yoshikawa, A.; Auffray, E.

    2016-01-01

    Roč. 816, Apr (2016), s. 176-183 ISSN 0168-9002 R&D Projects: GA ČR GAP204/12/0805 EU Projects: European Commission(XE) 644260 - INTELUM; European Commission(XE) 690599 - ASCIMAT Grant - others:EU COST Fast advanced Scintillator Timing (FAST)(XE) TD COST Action TD1401 Institutional support: RVO:68378271 Keywords : inorganic scintillators * medical imaging * calorimeters * time-of-flight * radiation tolerance Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.362, year: 2016

  15. In vitro mutants identification of banana (Musa sp.) with tolerance to toxin from Fusarium oxysporum f. sp cubense, treating buds with several gamma radiation doses; Identificacao in vitro de mutantes de banana maca (Musa sp.) tolerantes a toxina do Fusarium oxysporum f. sp. cubense, a partir de gemas tratadas com diferentes doses de radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Adriana Muniz Mendes de; Houllou-Kido, Laureen Michelle; Franca, Jose Geraldo Eugenio de [Empresa Pernambucana de Pesquisa Agropecuaria, Recife, PE (Brazil); Colaco, Waldeciro [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear

    1999-11-01

    Mutants of banana, obtained through treatment with different level of gamma-radiation (0; 10; 20; 30; 40 Gy), were initially cultivated in vitro in medium for rapid clonal propagation during 30 days. These treatment affected the shoot tips development ratio. Some plants developed necrosis and died, but some of the shoot tips emitted new gems. These material were cultivated in medium 20% of the toxin of Fusarium oxysporum cubense. During the selection period, the necrosis occurrence and death of susceptible shoot tips were observed. Whereas the tolerant shoot tips kept themselves green during the entire selection process. At the end of the selection process, eight shoot tips were obtained. (author) 7 refs.

  16. A Multirelational Account of Toleration

    DEFF Research Database (Denmark)

    Ferretti, Maria Paola; Lægaard, Sune

    2013-01-01

    Toleration classically denotes a relation between two agents that is characterised by three components: objection, power, and acceptance overriding the objection. Against recent claims that classical toleration is not applicable in liberal democracies and that toleration must therefore either be ...

  17. State, religion and toleration

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2009-01-01

    Contribution to Religion and State - From separation to cooperation? Legal-philosophical reflections for a de-secularized world. (IVR Cracow Special Workshop). Eds. Bart. C. Labuschagne & Ari M. Solon. Abstract: Toleration is indeed a complex phenomenon. A discussion of the concept will have...... to underline not only the broadmindedness and liberty of individuals or of groups, but also the relevant distinctions and arguments in political philosophy, epistemology, philosophy of religion and philosophical anthropology and their connection with educational issues. Through a discussion of these relations......, the essay argues three theses: (1) Toleration is not reducible to an ethics of spiritual freedom. (2) Toleration is not neutral to fanatism. (3) Toleration involves esteem for the person....

  18. Tolerance doses for treatment planning

    International Nuclear Information System (INIS)

    Lyman, J.T.

    1985-10-01

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD 5 ) or 50% (TD 50 ) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs

  19. A Theory of Tolerance

    OpenAIRE

    Corneo, Giacomo; Jeanne, Olivier

    2006-01-01

    We develop an economic theory of tolerance where styles of behaviour are invested with symbolic value. Value systems are endogenous and taught by parents to their children. In conjunction with actual behaviour, value systems determine the esteem enjoyed by individuals. Intolerant individuals have all symbolic value invested in a single style of behaviour, whereas tolerant people have diversified values. The proposed model identifies a link between the unpredictability of children's lifestyles...

  20. An abnormal carbohydrate tolerance in acromegaly

    International Nuclear Information System (INIS)

    Qi Jinwu

    1988-01-01

    An abnormal secretion of plasma human growth hormore (hGH) and insulin in 67 acromegalic patients had been previously treated by external pituitary radiation were studied. All subjects, following an overnight fast, a standard 100 g oral glucose tolerance test, were performed and venous blood samples were taken at 0, 30, 60, 120 and 180 min. They were measured for blood glucose, plasma insulin and hGH. The results of this study have shown that, of the 67 subjects, 23 cases had an abnormal glucose tolerance(34.32%). Diabetes was detected in 17 cases (23.37%) and 6 patients had decreased glucose tolerance(8.69%). In all, hGH levels were consistantly above 5 ng/ml and were not suppressed after an oral glucose load. In these patients, however, about one-third had abnormal glucose tolerance. Low plasma insulin response to glucose and that of the releasing were evident in them than the normal glucose tolerance and a healthy control group. In addition, the mechanism of the abnormal secretion of hGH and insulin were disscussed

  1. Radiation danger

    International Nuclear Information System (INIS)

    Gergely, S.M.

    1986-01-01

    The author is a journalist and has written the book 4 weeks after the Chernobyl accident because 'the experts have failed in informing on the consequences of Chernobyl in a way to keep the insecurity in the population within tolerable limits'. It is aimed at the interested layman. First the events as seen through the Austria media and the measures taken by the authorities during the 4 weeks are reviewed. In the rest of the books there is elementary information on some aspects of radioactivity, reactors and radiation limits although 'the connection between radioactivity and health is very complex'. (G.Q.)

  2. Radiation hormesis in plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Lee, Byung Hun; Shin, In Chul; Lim, Young Taek

    2000-04-01

    This research was performed to investigate the effects of low dose {gamma}-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as subsequent high doses of radiation or Phytophthora blight of pepper could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant (POD) were accomplished in the plant irradiated with different dose of {gamma}-ray. (author)

  3. Radiation hormesis in plant

    International Nuclear Information System (INIS)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Lee, Byung Hun; Shin, In Chul; Lim, Young Taek

    2000-04-01

    This research was performed to investigate the effects of low dose γ-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as subsequent high doses of radiation or Phytophthora blight of pepper could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant (POD) were accomplished in the plant irradiated with different dose of γ-ray. (author)

  4. Radiation injury to the nervous system

    International Nuclear Information System (INIS)

    Gutin, P.H.; Leibel, S.A.; Sneline, G.E.

    1991-01-01

    This book is designed to describe to the radiation biologist, radiation oncologist, neurologist, neurosurgeon, medical oncologist, and neuro-oncologist, the current state of knowledge about the tolerance of the nervous system to various kinds of radiation, the mechanisms of radiation injury, and how nervous system tolerance and injury are related to the more general problem of radiation damage to normal tissue of all types. The information collected here should stimulate interest in and facilitate the growing research effort into radiation injury to the nervous system

  5. Escaping the tolerance trap

    International Nuclear Information System (INIS)

    Hammoudeh, S.; Madan, V.

    1994-01-01

    In order to examine the implications of the weakening of OPEC's responsiveness in adjusting its production levels, this paper explicitly incorporates rigidity in the quantity adjustment mechanism, thereby extending previous research which assumed smooth quantity adjustments. The rigidity is manifested in a tolerance range for the discrepancy between the declared target price and that of the market. This environment gives rise to a 'tolerance trap' which impedes the convergence process and inevitably brings the market to a standstill before its reaches the targeted price and revenue objectives. OPEC's reaction to the standstill has important implications for the achievement of the target-based equilibrium and for the potential collapse of the market price. This paper examines OPEC's policy options in the tolerance trap and reveals that the optional policy in order to break this impasse and move closer to the equilibrium point is gradually to reduce output and not to flood the market. (Author)

  6. Fault tolerant linear actuator

    Science.gov (United States)

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  7. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  8. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    2004-01-01

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  9. Tolerances of microorganisms to extreme environmental conditions

    International Nuclear Information System (INIS)

    West, J.M.; Arme, S.C.

    1985-03-01

    Microbial isolates from sites relevant to the disposal of radioactive wastes have been subjected to extreme environmental conditions in order to ascertain their tolerance ability. Two groups were chosen, sulphate reducing bacteria and sulphur oxidising bacteria, because of their potential effects on waste containment. They have been subjected to high temperatures, pressures and radiation (delta-emissions) in optimal media conditions and their ability to tolerate the conditions has been ascertained by epifluorescence microscopy and adenosine tri-phosphate (ATP) analysis followed by 'culture-on' to assess post experimental viability. Results indicate that the sulphate reducers in general, are more tolerant to these conditions than the sulphur oxidisers, some proving to be thermophilic. The sulphate reducer showed increased growth rates, as determined by population numbers, at 50 0 C and survived at 80 0 C, 4,500 psig (310 bar) with no subsequent loss in viability. Gamma irradiation of this group and an isolate of 10 5 rad over 4 hours had no effect on population numbers or viability. Such resistances are not apparent with the sulphur oxidisers whose numbers decreased with increasing radiation dose and are destroyed with pressure. (author)

  10. Toleration, Groups, and Multiculturalism

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    have the ability to interfere with the group’s activities, an object of dislike or disapproval, an agent enjoying non-interference or a moral patient. This means that 'toleration of groups' can mean quite different things depending on the exact meaning of 'group' in relation to each component...

  11. Fault Tolerant Control Systems

    DEFF Research Database (Denmark)

    Bøgh, S. A.

    This thesis considered the development of fault tolerant control systems. The focus was on the category of automated processes that do not necessarily comprise a high number of identical sensors and actuators to maintain safe operation, but still have a potential for improving immunity to component...

  12. Toleration and its enemies

    DEFF Research Database (Denmark)

    Jarvad, Ib Martin

    2010-01-01

    After a presentation of the development of freedom of expression in Danish constitutional law, to freedom of the press in European human rights law - the Jersild case- to a right to mock and ridicule other faiths in recent Danish practice, the essay of Locke on toleration is examined, its...

  13. A little toleration, please

    Science.gov (United States)

    McKnight, C.

    2000-01-01

    Value pluralism does not imply relativism or subjectivism about values. What it does is allow respect for an at least limited toleration of values with which one may profoundly disagree. Thus a doctor can respect the autonomy of a patient whose values he does not share. Key Words: Pluralism • multiculturalism • relativism • subjectivism • patient autonomy PMID:11129842

  14. Deconstructing tolerance with clobazam

    Science.gov (United States)

    Wechsler, Robert T.; Sankar, Raman; Montouris, Georgia D.; White, H. Steve; Cloyd, James C.; Kane, Mary Clare; Peng, Guangbin; Tworek, David M.; Shen, Vivienne; Isojarvi, Jouko

    2016-01-01

    Objective: To evaluate potential development of tolerance to adjunctive clobazam in patients with Lennox-Gastaut syndrome. Methods: Eligible patients enrolled in open-label extension study OV-1004, which continued until clobazam was commercially available in the United States or for a maximum of 2 years outside the United States. Enrolled patients started at 0.5 mg·kg−1·d−1 clobazam, not to exceed 40 mg/d. After 48 hours, dosages could be adjusted up to 2.0 mg·kg−1·d−1 (maximum 80 mg/d) on the basis of efficacy and tolerability. Post hoc analyses evaluated mean dosages and drop-seizure rates for the first 2 years of the open-label extension based on responder categories and baseline seizure quartiles in OV-1012. Individual patient listings were reviewed for dosage increases ≥40% and increasing seizure rates. Results: Data from 200 patients were included. For patients free of drop seizures, there was no notable change in dosage over 24 months. For responder groups still exhibiting drop seizures, dosages were increased. Weekly drop-seizure rates for 100% and ≥75% responders demonstrated a consistent response over time. Few patients had a dosage increase ≥40% associated with an increase in seizure rates. Conclusions: Two-year findings suggest that the majority of patients do not develop tolerance to the antiseizure actions of clobazam. Observed dosage increases may reflect best efforts to achieve seizure freedom. It is possible that the clinical development of tolerance to clobazam has been overstated. ClinicalTrials.gov identifier: NCT00518713 and NCT01160770. Classification of evidence: This study provides Class III evidence that the majority of patients do not develop tolerance to clobazam over 2 years of treatment. PMID:27683846

  15. Heat tolerance in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari

    As a consequence of global climate change, heat stress together with other abiotic stresses will remain an important determinant of future food security. Wheat (Triticum aestivum L.) is the third most important crop of the world feeding one third of the world population. Being a crop of temperate...... climate, wheat is sensitive to heat stress. We need to understand how our crops will perform in these changing climatic conditions and how we can develop varieties, which are more tolerant. The PhD study focussed on understanding heat tolerance in wheat with a combined approach of plant physiology...... and quantitative genetics in particular, plant phenotyping based quantitative trait loci (QTL) discovery for a physiological trait under heat stress. Chlorophyll a fluorescence trait, Fv/Fm was used as a phenotyping tool, as it reflects the effect of heat stress on maximum photochemical efficiency of photosystem...

  16. Radiation hormesis in plant

    International Nuclear Information System (INIS)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Cun, Ki Jung; Shin, In Chul; Lim, Young Taek

    1999-04-01

    This research was performed to investigate the effects of low dose γ-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as acid rain or soil types could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant enzyme (POD) were accomplished in the plant irradiated with difference dosage of γ-ray

  17. Radiation hormesis in plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Cun, Ki Jung; Shin, In Chul; Lim, Young Taek

    1999-04-01

    This research was performed to investigate the effects of low dose {gamma}-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as acid rain or soil types could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant enzyme (POD) were accomplished in the plant irradiated with difference dosage of {gamma}-ray.

  18. Radiation effects after low dose chronic long-term exposure

    International Nuclear Information System (INIS)

    Fliedner, T.M.; Friesecke, I.

    1997-01-01

    This document approaches the radiation effects after low dose chronic long-term exposure, presenting examples occurred, the pathophysiologic mechanisms for cell system tolerance in elevated radiation fields, and the diagnostic and therapeutic possibilities

  19. Radiation-resistant asporogenic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Yano, K [Tokyo Univ. (Japan). Faculty of Agriculture

    1975-09-01

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned.

  20. Radiation-resistant asporogenic bacteria

    International Nuclear Information System (INIS)

    Yano, Keiji

    1975-01-01

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned. (Tsukamoto, Y.)

  1. Socially-Tolerable Discrimination

    OpenAIRE

    Amegashie, J. Atsu

    2008-01-01

    History is replete with overt discrimination on the basis of race, gender, age, citizenship, ethnicity, marital status, academic performance, health status, volume of market transactions, religion, sexual orientation, etc. However, these forms of discrimination are not equally tolerable. For example, discrimination based on immutable or prohibitively unalterable characteristics such as race, gender, or ethnicity is much less acceptable. Why? I develop a simple rent-seeking model of conflict w...

  2. Basic radiation effects in nuclear power electronics technology

    International Nuclear Information System (INIS)

    Gover, J.E.; Srour, J.R.

    1985-05-01

    An overview is presented of the effects of radiation in microelectronics technology. The approach taken throughout these notes is to review microscopic phenomena associated with radiation effects and to show how these lead to macroscopic effects in semiconductor devices and integrated circuits. Bipolar integrated circuits technology is reviewed in Appendix A. Appendix B gives present and future applications of radiation-tolerant microelectronics in nuclear power applications as well as the radiation tolerance requirements of these applications

  3. Fault Tolerant Computer Architecture

    CERN Document Server

    Sorin, Daniel

    2009-01-01

    For many years, most computer architects have pursued one primary goal: performance. Architects have translated the ever-increasing abundance of ever-faster transistors provided by Moore's law into remarkable increases in performance. Recently, however, the bounty provided by Moore's law has been accompanied by several challenges that have arisen as devices have become smaller, including a decrease in dependability due to physical faults. In this book, we focus on the dependability challenge and the fault tolerance solutions that architects are developing to overcome it. The two main purposes

  4. Toleration, Synthesis or Replacement?

    DEFF Research Database (Denmark)

    Holtermann, Jakob v. H.; Madsen, Mikael Rask

    2016-01-01

    , in order to answer is not yet another partisan suggestion, but rather an attempt at making intelligible both the oppositions and the possibilities of synthesis between normative and empirical approaches to law. Based on our assessment and rational reconstruction of current arguments and positions, we...... therefore outline a taxonomy consisting of the following three basic, ideal-types in terms of the epistemological understanding of the interface of law and empirical studies: toleration, synthesis and replacement. This tripartite model proves useful with a view to teasing out and better articulating...

  5. Radiation chemistry

    International Nuclear Information System (INIS)

    Rodgers, F.; Rodgers, M.A.

    1987-01-01

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

  6. Ethnopoly promotes tolerance

    CERN Document Server

    CERN Bulletin

    2010-01-01

    On Friday 23 April, 225 primary school children from the eight schools in Meyrin-Cointrin and their accompanying adults took part in a big game of Ethnopoly. Private individuals, associations, administrations, shopkeepers and CERN all opened their doors to them to talk about their countries, their customs and what they are doing to promote tolerance and integration.   The CERN stand set up at ForumMeyrin for the Ethnopoly game. Scurrying from one place to another, the 10 and 11 year olds were made aware of the rich cultural diversity of their commune, which is home to 130 different nationalities. Physicists and engineers from CERN took up residence in the Forum Meyrin for the day in order to talk to the children about the advantages of international collaboration, a subject dear to the Organization's heart. They welcomed around fifty children in the course of the day, conveying to them a message of tolerance: despite their differences, the 10,000 scientists and other members of the CERN...

  7. Secondary Disease in Radiation Chimeras

    Energy Technology Data Exchange (ETDEWEB)

    Congdon, C. C. [Biology Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-07-15

    A review of research dealing directly or indirectly with the development of bidirectional tolerance in radiation chimeras has been made, emphasizing some of the contemporary research on this subject in Oak Ridge and Knoxville. By controlling such factors as cell dose, age of donor animal and day of cell injection, it was possible to achieve bidirectional tolerance. Attempts to reduce bidirectional tolerance in favour of increasing the graft-versus-host reaction were less successful. Hypoxic caging demonstrated a new approach to achieving bidirectional tolerance through physiological competition for growth. Graft-versus-host reactions have a lower growth priority than marrow regeneration or erythropoietic hyperplasia. Study of pathologic processes, immunologic capability and the-biochemical lesions in radiation chimeras all lead to new ideas that involve bidirectional tolerance. The investigations on dose rate in radiation suppression of the immune response and on LD{sub 50} (30- to 90-day)values after injection of different numbers of marrow cells all have a bearing on control of the host-versus-graft response and therefore are important in understanding bidirectional tolerance. (author)

  8. Fault-tolerant computing systems

    International Nuclear Information System (INIS)

    Dal Cin, M.; Hohl, W.

    1991-01-01

    Tests, Diagnosis and Fault Treatment were chosen as the guiding themes of the conference. However, the scope of the conference included reliability, availability, safety and security issues in software and hardware systems as well. The sessions were organized for the conference which was completed by an industrial presentation: Keynote Address, Reconfiguration and Recover, System Level Diagnosis, Voting and Agreement, Testing, Fault-Tolerant Circuits, Array Testing, Modelling, Applied Fault Tolerance, Fault-Tolerant Arrays and Systems, Interconnection Networks, Fault-Tolerant Software. One paper has been indexed separately in the database. (orig./HP)

  9. Salt Tolerance in Soybean

    Institute of Scientific and Technical Information of China (English)

    Tsui-Hung Phang; Guihua Shao; Hon-Ming Lam

    2008-01-01

    Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.

  10. Delay tolerant networks

    CERN Document Server

    Gao, Longxiang; Luan, Tom H

    2015-01-01

    This brief presents emerging and promising communication methods for network reliability via delay tolerant networks (DTNs). Different from traditional networks, DTNs possess unique features, such as long latency and unstable network topology. As a result, DTNs can be widely applied to critical applications, such as space communications, disaster rescue, and battlefield communications. The brief provides a complete investigation of DTNs and their current applications, from an overview to the latest development in the area. The core issue of data forward in DTNs is tackled, including the importance of social characteristics, which is an essential feature if the mobile devices are used for human communication. Security and privacy issues in DTNs are discussed, and future work is also discussed.

  11. Radiation and radiation protection

    International Nuclear Information System (INIS)

    Landfermann, H.H.; Solbach, C.

    1992-11-01

    The brochure explains the major types of radiation, the radiation sources, effects, uses, and risks, as well as the regulatory system adopted by the government in order to keep the risks as low as possible. (orig./DG) [de

  12. Tolerance of the brain and spinal cord to conventional irradiation

    International Nuclear Information System (INIS)

    Leibel, S.A.; Sheline, G.E.

    1991-01-01

    In this paper, the authors discuss the clinical features and time-dose relations associated with radiation injury of the brain and spinal cord. Limits of radiation tolerance have not been well defined. In general, the literature on central nervous system (CNS) injury is anecdotal and incomplete. Relevant information such as total dose at the site of injury, size and number of treatment fractions, overall treatment time, radiation field arrangement, and volume treated is often omitted. Therefore, it is difficult to formulate firm conclusions regarding the risk of radiation injury and its association with any given set of therapeutic approaches and patient characteristics. The material presented in this chapter is based on conventional photon and gamma irradiation, and does not apply to large single dose fractions used in stereotaxic small-field external irradiation (radiosurgery) or to other forms of ionizing radiation such as neutrons or heavy particles

  13. School-industry partnership - Radiation

    International Nuclear Information System (INIS)

    Ruuskanen, Antti

    1995-01-01

    'Mere are several well-known obstacles to tolerance of nuclear power such as wastes and risks of accident. However, there is a single underlying factor which is, indeed, poorly understood by the general public, namely ionizing radiation. Radiation is one of those natural phenomena not taught to everybody in school. That is why IVO decided to co-operate with schools and teachers, and arrange lessons about radiation. Considering that some parents of pupils follow closely what their children are taught in school, this school-industry partnership may indirectly inform some adults about radiation, too

  14. School-industry partnership - Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ruuskanen, Antti [IVO Group (Finland)

    1995-07-01

    'Mere are several well-known obstacles to tolerance of nuclear power such as wastes and risks of accident. However, there is a single underlying factor which is, indeed, poorly understood by the general public, namely ionizing radiation. Radiation is one of those natural phenomena not taught to everybody in school. That is why IVO decided to co-operate with schools and teachers, and arrange lessons about radiation. Considering that some parents of pupils follow closely what their children are taught in school, this school-industry partnership may indirectly inform some adults about radiation, too.

  15. Tolerance of the human spinal cord to single dose radiosurgery

    International Nuclear Information System (INIS)

    Ryu, S.; Zhu, G.; Yin, F.-F.; Ajlouni, M.; Kim, J.H.

    2003-01-01

    Tolerance of the spinal cord to the single dose of radiation is not well defined. Although there are cases of human spinal cord tolerance from re-irradiation to the same cord level, the information about the tolerance of human spinal cord to single large dose of radiosurgery is not available. We carried out spinal radiosurgery to treat spinal metastasis and studied the single dose tolerance of the human spinal cord in an ongoing dose escalation paradigm. A total of 39 patients with 48 lesions of spinal metastasis were treated with single dose radiosurgery at Henry Ford Hospital. The radiosurgery dose was escalated from 8 Gy to 16 Gy at 2 Gy increment. The radiation dose was prescribed to periphery of the spinal tumor. The radiation dose to the spinal cord was estimated by computerized dosimetry. The median follow-up time was 10 months (range 6-18 months) from the radiosurgery. The endpoint of the study was to demonstrate the efficacy of the spinal radiosurgery and to determine the tolerance of human spinal cord to single dose radiosurgery. The dose to the spinal cord was generally less than 50 % of the prescribed radiation dose. The volume of the spinal cord that received higher than this dose was less than 20 % of the anterior portion of the spinal cord. Maximum single dose of 8 Gy was delivered to the anterior 20 % of the spinal cord in this dose escalation study. The dose volume histogram will be presented. There was no acute or subacute radiation toxicity detected clinically and radiologically during the maximum follow-up of 20 months. Further dose escalation is in progress. The single tolerance dose of the human spinal cord appears to be at least 8 Gy when it was given to the 20 % of the cord volume, although the duration of follow up is not long enough to detect severe late cord toxicity. This study offers a valuable radiobiological basis of the normal spinal cord tolerance, and opens spinal radiosurgery as a safe treatment for spinal metastasis

  16. Radiation measurement

    International Nuclear Information System (INIS)

    Go, Sung Jin; Kim, Seung Guk; No, Gyeong Seok; Park, Myeong Hwan; Ann, Bong Seon

    1998-03-01

    This book explains technical terms about radiation measurement, which are radiation, radiation quantity and unit such as prefix of international unit, unit for defence purposes of radiation, coefficient of radiation and interaction, kinds and principles of radiation detector, ionization chamber, G-M counter, G-M tube, proportional counter, scintillation detector, semiconductor radiation detector, thermoluminescence dosimeter, PLD, others detector, radiation monitor, neutron detector, calibration of radiation detector, statistics of counting value, activation analysis and electronics circuit of radiation detector.

  17. Shaping tolerant attitudes towards immigrants

    DEFF Research Database (Denmark)

    Rapp, Carolin

    2017-01-01

    This article contributes to the ongoing discussion on how tolerance may be fostered in Western European countries and to the question of how contextual factors such as welfare state expenditures may contribute to this formation. Tolerance is understood as a basic democratic principle that helps c...

  18. Legal Quality, Inequality, and Tolerance

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    Previous findings suggest that income inequality leads to lower legal quality. This paper argues that voters' tolerance of inequality exerts an additional influence. Empirical findings suggest that inequality leads to lower legal quality due to its effect on trust while the tolerance of inequality...

  19. Legal Quality, Inequality, and Tolerance

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    2004-01-01

    Previous findings suggest that income inequality leads to lower legal quality. This paper argues that voters' tolerance of inequality exerts an additional influence. Empirical findings suggest that inequality leads to lower legal quality due to its effect on trust while the tolerance of inequality...

  20. Tolerance Issue in Kazakh Culture

    Science.gov (United States)

    Aubakirova, Saltanat S.; Ismagambetova, Zukhra N.; Karabayeva, Aliya G.; Rysbekova, Shamshiya S.; Mirzabekova, Alma Sh.

    2016-01-01

    In this article the authors reveal the basic cultural mechanisms that influence the formation of the tolerance strategy in Kazakh and Kazakhstan society, show its basic directions, as well as its importance for the modern Kazakhstan society and the formation of intercultural communication with foreign countries. Tolerance is a necessary element of…

  1. Tolerance-Based Feature Transforms

    NARCIS (Netherlands)

    Reniers, Dennie; Telea, Alexandru

    2007-01-01

    Tolerance-based feature transforms (TFTs) assign to each pixel in an image not only the nearest feature pixels on the boundary (origins), but all origins from the minimum distance up to a user-defined tolerance. In this paper, we compare four simple-to-implement methods for computing TFTs on binary

  2. Radiation hardness assurances categories for COTS technologies

    International Nuclear Information System (INIS)

    Hash, G.L.; Shaneyfelt, M.R.; Sexton, F.W.; Winokur, P.S.

    1997-01-01

    A comparison of the radiation tolerance of three commercial, and one radiation hardened SRAM is presented for four radiation environments. This work has shown the difficulty associated with strictly categorizing a device based solely on its radiation response, since its category depends on the specific radiation environment considered. For example, the 3.3-V Paradigm SRAM could be considered a radiation-tolerant device except for its SEU response. A more useful classification depends on the methods the manufacturer uses to ensure radiation hardness, i.e. whether specific design and process techniques have been used to harden the device. Finally, this work has shown that burned-in devices may fail functionally as much as 50% lower in total dose environments than non-burned-in devices. No burn-in effect was seen in dose-rate upset, latchup, or SEE environments. The user must ensure that total dose lot acceptance testing was performed on burned-in devices

  3. Radiation tolerance of Si{sub 1−y}C{sub y} source/drain n-type metal oxide semiconductor field effect transistors with different carbon concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, Toshiyuki, E-mail: nakashima_t@cdk.co.jp [Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki (Japan); Chuo Denshi Kogyo Co., Ltd., 3400 Kohoyama, Matsubase, Uki, Kumamoto (Japan); Asai, Yuki; Hori, Masato; Yoneoka, Masashi; Tsunoda, Isao; Takakura, Kenichiro [Kumamoto National College of Technology, 2659-2 Suya, Koshi, Kumamoto 861-1102 (Japan); Gonzalez, Mireia Bargallo [Institut de Microelectronica de Barcelona (Centre Nacional de Microelectronica — Consejo Superior de Investigaciones Cientificas) Campus UAB, 08193 Bellaterra (Spain); Simoen, Eddy [imec, Kapeldreef 75, B-3001 Leuven (Belgium); Claeys, Cor [imec, Kapeldreef 75, B-3001 Leuven (Belgium); Department of Electrical Engineering, KU Leuven, Kasteelpark Arenberg 10, B-3001 Leuven (Belgium); Yoshino, Kenji [Interdisciplinary Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki (Japan)

    2014-04-30

    The 2-MeV electron radiation damage of silicon–carbon source/drain (S/D) n-type metal oxide semiconductor field effect transistors with different carbon (C) concentrations is studied. Before irradiation, an enhancement of the electron mobility with C concentration of the S/D stressors is clearly observed. On the other hand, after electron irradiation, both the threshold voltage shift and the maximum electron mobility degradation are independent on the C concentration for all electron fluences studied. These results indicate that the strain induced electron mobility enhancement due to the C doping is retained after irradiation in the studied devices. - Highlights: • We have investigated the electron irradiation effect of the Si{sub 1−y}C{sub y} S/D n-MOSFETs. • The threshold voltage variations by irradiation are independent on the C doping. • The electron-mobility decreased for all C concentrations by electron irradiation. • The strain induced mobility enhancement effect is retained after irradiation.

  4. Safety and radiation-enhancing effect of sodium glycididazole in loco regionally advanced laryngeal cancers previously treated with platinum-containing chemotherapy regimens: a preliminary report; Tolerance et effet radiosensibilisateur du sodium glycididazole chez des patients atteints de cancer du larynx localement evolue ayant prealablement recu une chimiotherapie a base de cisplatine: rapport preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Y.C.; Wu, R.; Xu, Z.G.; Zhang, X.Y.; Wu, L.N.; Wang, Y.M.; Zheng, W.; Chen, X.D.; Chi, F.; Zhang, Z.Y.; Li, X.; Jin, X.Y.; Chen, W.; Wang, S.L.; Xiao, F.D.; Wang, E.Y.; Dong, X.Q.; Jia, M.X.; Li, Y. [China Medical Univ., Dept. of Medical Oncology, Shengjing Hospital, Shenyang, PR (China); Fan, G.L. [Harbin First Hospital, Dept. of Otorhinolaryngology, PR (China); Hao, S.H.; Zhang, L.B.; Zhang, H.B. [General Hospital of Shenyang Military Region, Dept. of Nuclear Medicine and Radiology, Shenyang, PR (China); Xia, H.H.X. [Novartis Pharmaceuticals Corporation, East Hanover, New Jersey (United States)

    2010-01-15

    Purpose: To determine the safety and radiation-enhancing effect of sodium glycididazole in laryngeal squamous cell carcinoma (stage T3-4,N0-3,M0) with conventional radiotherapy. Patients and methods: Patients with locoregional advanced laryngeal cancer (stage T3-4,N0-3,M0) were included: group 1(control, n = 30)were not administered of sodium glycididazole; group 2 (test, n = 30) received sodium glycididazole at a dose of 700 mg/m2 intravenous infusion 30 minutes before radiotherapy three times a week. Surrogate end-points of efficacy were tumor and nodal size. Safety parameters were vomiting, nausea, mucositis, laryngeal edema, esophagus and skin reaction, dysphagia, dyspnea, neurological deficit. Patients were evaluated weekly during treatment for 7 weeks and thereafter monthly for 3 months. Results: In the test, the overall response rate was 88.89% (95% CI, 71.00-97.00%) at 7 weeks and 92.59% (95% CI, 76.00 to 99.00%) at 1 month of follow-up. In the control, the overall response rate was 62.5% (95% CI, 41.00 to 81.00%) at 7 weeks and 58.33% (95% CI, 37.00 to 78.00%) at 1 month of follow-up. The short-term locoregional response rate was better in the test group at 7 weeks (p = 0.027) and at 1 month (p = 0.005) of follow-up. The test group had significantly more nausea and vomiting in weeks 1 (p = 0.047), 2 (p = 0.007), and 3 (p = 0.01) of treatment. Conclusions: The study indicates sodium glycididazole is an effective radiation-enhancing agent that improves short-term locoregional control and is well tolerated in patients with loco regionally advanced laryngeal cancer. (authors)

  5. Radiation induced liver disease: A clinical update

    International Nuclear Information System (INIS)

    Benson, R.; Madan, R.; Chander, S.; Kilambi, R.

    2016-01-01

    Radiation-induced liver disease (RILD) or radiation hepatitis is a sub-acute form of liver injury due to radiation. It is one of the most dreaded complications of radiation which prevents radiation dose escalation and re irradiation for hepatobiliary or upper gastrointestinal malignancies. This complication should be kept in mind whenever a patient is planned for irradiation of these malignancies. Although, incidence of RILD is decreasing due to better knowledge of liver tolerance, improved investigation modalities and modern radiation delivery techniques, treatment options are still limited. In this review article, we have focussed on pathophysiology, risk factors, prevention and management of RILD

  6. Tolerance and chimerism.

    Science.gov (United States)

    Kolb, Hans-Jochem; Guenther, Wolfgang; Gyurkocza, Boglarka; Hoetzl, Florian; Simoes, Belinda; Falk, Christine; Schleuning, Michael; Ledderose, Georg

    2003-05-15

    Stem-cell transplantation from human leukocyte antigen (HLA)-haploidentical family members carries a high risk of rejection and graft-versus-host disease (GVHD) if donor and recipient differ by more than one HLA antigen. The authors have developed treatment protocols from studies in dog leukocyte antigen-haploidentical dogs that prevent rejection and modify GVHD to the extent that patients with aggressive hematologic neoplasia can be treated with success. Principal improvements have been achieved in the use of cyclophosphamide and total-body irradiation for conditioning and T-cell depletion for prevention of GVHD. More recently, the combination of marrow and CD6-depleted mobilized donor blood cells (MDBC) has been introduced for HLA-haploidentical transplantation on the basis that CD6-depleted MDBC contain immunoregulatory cells besides stem cells and natural killer cells. Clinical results are reported on 36 patients with high-risk hematologic neoplasia. The results encourage the use of HLA-haploidentical stem-cell transplantation at an earlier stage of the disease. This method could also be of use for tolerance induction in organ transplantation.

  7. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  8. Mechanical tolerance stackup and analysis

    CERN Document Server

    Fischer, Bryan R

    2011-01-01

    Use Tolerance Analysis Techniques to Avoid Design, Quality, and Manufacturing Problems Before They Happen Often overlooked and misunderstood, tolerance analysis is a critical part of improving products and their design processes. Because all manufactured products are subject to variation, it is crucial that designers predict and understand how these changes can affect form, fit, and function of parts and assemblies--and then communicate their findings effectively. Written by one of the developers of ASME Y14.5 and other geometric dimension and tolerancing (GD&T) standards, Mechanical Tolerance

  9. Advanced cloud fault tolerance system

    Science.gov (United States)

    Sumangali, K.; Benny, Niketa

    2017-11-01

    Cloud computing has become a prevalent on-demand service on the internet to store, manage and process data. A pitfall that accompanies cloud computing is the failures that can be encountered in the cloud. To overcome these failures, we require a fault tolerance mechanism to abstract faults from users. We have proposed a fault tolerant architecture, which is a combination of proactive and reactive fault tolerance. This architecture essentially increases the reliability and the availability of the cloud. In the future, we would like to compare evaluations of our proposed architecture with existing architectures and further improve it.

  10. Tolerance to and cross tolerance between ethanol and nicotine.

    Science.gov (United States)

    Collins, A C; Burch, J B; de Fiebre, C M; Marks, M J

    1988-02-01

    Female DBA mice were subjected to one of four treatments: ethanol-containing or control diets, nicotine (0.2, 1.0, 5.0 mg/kg/hr) infusion or saline infusion. After removal from the liquid diets or cessation of infusion, the animals were challenged with an acute dose of ethanol or nicotine. Chronic ethanol-fed mice were tolerant to the effects of ethanol on body temperature and open field activity and were cross tolerant to the effects of nicotine on body temperature and heart rate. Nicotine infused animals were tolerant to the effects of nicotine on body temperature and rotarod performance and were cross tolerant to the effects of ethanol on body temperature. Ethanol-induced sleep time was decreased in chronic ethanol- but not chronic nicotine-treated mice. Chronic drug treatment did not alter the elimination rate of either drug. Chronic ethanol treatment did not alter the number or affinity of brain nicotinic receptors whereas chronic nicotine treatment elicited an increase in the number of [3H]-nicotine binding sites. Tolerance and cross tolerance between ethanol and nicotine is discussed in terms of potential effects on desensitization of brain nicotinic receptors.

  11. Accident tolerant fuel analysis

    International Nuclear Information System (INIS)

    2014-01-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced ''RISMC toolkit'' that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional ''accident-tolerant'' (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant

  12. Radiation hard cryogenic silicon detectors

    International Nuclear Information System (INIS)

    Casagrande, L.; Abreu, M.C.; Bell, W.H.; Berglund, P.; Boer, W. de; Borchi, E.; Borer, K.; Bruzzi, M.; Buontempo, S.; Chapuy, S.; Cindro, V.; Collins, P.; D'Ambrosio, N.; Da Via, C.; Devine, S.; Dezillie, B.; Dimcovski, Z.; Eremin, V.; Esposito, A.; Granata, V.; Grigoriev, E.; Hauler, F.; Heijne, E.; Heising, S.; Janos, S.; Jungermann, L.; Konorov, I.; Li, Z.; Lourenco, C.; Mikuz, M.; Niinikoski, T.O.; O'Shea, V.; Pagano, S.; Palmieuri, V.G.; Paul, S.; Pirollo, S.; Pretzl, K.; Rato, P.; Ruggiero, G.; Smith, K.; Sonderegger, P.; Sousa, P.; Verbitskaya, E.; Watts, S.; Zavrtanik, M.

    2002-01-01

    It has been recently observed that heavily irradiated silicon detectors, no longer functional at room temperature, 'resuscitate' when operated at temperatures below 130 K. This is often referred to as the 'Lazarus effect'. The results presented here show that cryogenic operation represents a new and reliable solution to the problem of radiation tolerance of silicon detectors

  13. Improvement of CMOS VLSI rad tolerance by processing technics

    International Nuclear Information System (INIS)

    Guyomard, D.; Desoutter, I.

    1986-01-01

    The following study concerns the development of integrated circuits for fields requiring only relatively low radiation tolerance levels, and especially for the civil spatial district area. Process modifications constitute our basic study. They have been carried into effects. Our work and main results are reported in this paper. Well known 2.5 and 3 μm CMOS technologies are under our concern. A first set of modifications enables us to double the cumulative dose tolerance of a 4 Kbit SRAM, keeping at the same time the same kind of damage. We obtain memories which tolerate radiation doses as high as 16 KRad(Si). Repetitivity of the results, linked to the quality assurance of this specific circuit, is reported here. A second set of modifications concerns the processing of gate array. In particular, the choice of the silicon substrate type, (epitaxy substrate), is under investigation. On the other hand, a complete study of a test vehicule allows us to accurately measure the rad tolerance of various components of the Cell library [fr

  14. Morphine tolerance offers protection from radiogenic performance deficits

    International Nuclear Information System (INIS)

    Mickley, G.A.; Stevens, K.E.; Burrows, J.M.; White, G.A.; Gibbs, G.L.

    1983-01-01

    When rats are exposed to a sufficiently large dose of ionizing radiation they exhibit lethargy, hypokinesia, and deficits in performance. These and other behavioral changes parallel those often observed in this species after a large dose of morphine. Since the release of endogenous opiates has been implicated in some stress reactions, we sought to determine if they might play a part in radiogenic behavioral deficits. Rats were trained to criterion on a signaled avoidance task. Some subjects were then implanted with a pellet containing 75 mg of morphine. Other animals received placebo implants. Over a number of days, morphine tolerance was evaluated by measurement of body temperature changes. Prior to 2500 rad 60 Co exposure or sham irradiation, morphine (or placebo) pellets were removed. Twenty-four hours later rats were retested to assess their performance on the avoidance task. Morphine-tolerant subjects performed significantly better than the irradiated placebo-implanted group and no differently than morphine-tolerant/sham-irradiated animals. Morphine tolerance seems to provide a degree of behavioral radiation resistance. These data are consistent with the hypothesis that endogenous opiate hyperexcretion may play some part in the behavioral deficits often observed after irradiation

  15. TEMPERATURE TOLERANCES AND OSMOREGULATION IN ...

    African Journals Online (AJOL)

    The salinity and temperature tolerances of some burrowiq bivalves which oc:eur ... Along most of the estuary the salinity normally remains close to that of seawater (35'/.) ...... grapsoid crabs, Hemigrapsus nudus and Hemigrapsus oregonensis.

  16. TOLERANCE OF Abelmoschus esculentus (L

    African Journals Online (AJOL)

    Cletus

    Key word: - Tolerance, diesel oil, polluted soil, Abelmoschus esculentus. INTRODUCTION ... errors -of the mean values were calculated for the replicate readings and data .... African Schools and Colleges, 2nd Ed. University Press Limited ...

  17. Antibiotic tolerance and microbial biofilms

    DEFF Research Database (Denmark)

    Folkesson, Anders

    Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We study the dynamics of antibiotic action within hydrodynamic flow chamber biofilms of Escherichia coli and Pseudomonas aeruginosa using isogenic mutants and fluorescent gene...... expression reporters and we address the question of how biofilm organization affects antibiotic susceptibility. The dynamics of microbial killing is monitored by viable count determination, and confocal laser microscopy. Our work shows that the apparent increased antibiotic tolerance is due to the formation...... of antibiotic tolerant subpopulations within the biofilm. The formation of these subpopulations is highly variable and dependent on the antibiotic used, the biofilm structural organization and the induction of specific tolerance mechanisms....

  18. Feasibility Analysis and Design of a Fault Tolerant Computing System: A TMR Microprocessor System Design of 64-Bit Cots Microprocessors

    National Research Council Canada - National Science Library

    Eken, Huseyin

    2001-01-01

    The purpose of this thesis is to analyze and determine the feasibility of implementing a fault tolerant computing system that is able to function in the presence of radiation induced Single Event Upsets (SEU...

  19. Cytokine regulation of immune tolerance

    OpenAIRE

    Wu, Jie; Xie, Aini; Chen, Wenhao

    2014-01-01

    The immune system provides defenses against invading pathogens while maintaining immune tolerance to self-antigens. This immune homeostasis is harmonized by the direct interactions between immune cells and the cytokine environment in which immune cells develop and function. Herein, we discuss three non-redundant paradigms by which cytokines maintain or break immune tolerance. We firstly describe how anti-inflammatory cytokines exert direct inhibitory effects on immune cells to enforce immune ...

  20. Women’s G Tolerance

    Science.gov (United States)

    1986-08-01

    for the groups matched by age (70 pairs), weight sickness, uncomfortable feelings of distension in arms (26 pairs), and act~vity status (84 pairs...mass-spring-damper) s ,stem Straining G tolerance, being dpendent on skeletal having a resonant frequency above about I Hz. As muscular strength and...of the women’s G tolerance stud\\ scclic variations in muscular strength and endurance. was below 0.1 Hz (11), the production of any significant

  1. Fault-tolerant rotary actuator

    Science.gov (United States)

    Tesar, Delbert

    2006-10-17

    A fault-tolerant actuator module, in a single containment shell, containing two actuator subsystems that are either asymmetrically or symmetrically laid out is provided. Fault tolerance in the actuators of the present invention is achieved by the employment of dual sets of equal resources. Dual resources are integrated into single modules, with each having the external appearance and functionality of a single set of resources.

  2. Behavioral Tolerance to Anticholinergic Agents

    Science.gov (United States)

    1986-11-20

    Medicine , 47, 137-141. 7. Kurtz, P.J. (1977) Behavioral and biochemical effects of the carbamate insecticide, mobam. Pharmacology Biochemistry & Behavior...tolerance to marihuana in rats. Pharmacology Biochemistry and Behavior, 1, 73-76. 43 40. Olson, J. and Carder, B. (1974) Behavioral tolerance to... marihuana as a function of amount of prior training. Pharmacology Biochemistry and Behavior, 2, 243-247. 41. Sidman, M. (1960) Tactics of Scientific

  3. Prediction of Glucose Tolerance without an Oral Glucose Tolerance Test

    Directory of Open Access Journals (Sweden)

    Rohit Babbar

    2018-03-01

    Full Text Available IntroductionImpaired glucose tolerance (IGT is diagnosed by a standardized oral glucose tolerance test (OGTT. However, the OGTT is laborious, and when not performed, glucose tolerance cannot be determined from fasting samples retrospectively. We tested if glucose tolerance status is reasonably predictable from a combination of demographic, anthropometric, and laboratory data assessed at one time point in a fasting state.MethodsGiven a set of 22 variables selected upon clinical feasibility such as sex, age, height, weight, waist circumference, blood pressure, fasting glucose, HbA1c, hemoglobin, mean corpuscular volume, serum potassium, fasting levels of insulin, C-peptide, triglyceride, non-esterified fatty acids (NEFA, proinsulin, prolactin, cholesterol, low-density lipoprotein, HDL, uric acid, liver transaminases, and ferritin, we used supervised machine learning to estimate glucose tolerance status in 2,337 participants of the TUEF study who were recruited before 2012. We tested the performance of 10 different machine learning classifiers on data from 929 participants in the test set who were recruited after 2012. In addition, reproducibility of IGT was analyzed in 78 participants who had 2 repeated OGTTs within 1 year.ResultsThe most accurate prediction of IGT was reached with the recursive partitioning method (accuracy = 0.78. For all classifiers, mean accuracy was 0.73 ± 0.04. The most important model variable was fasting glucose in all models. Using mean variable importance across all models, fasting glucose was followed by NEFA, triglycerides, HbA1c, and C-peptide. The accuracy of predicting IGT from a previous OGTT was 0.77.ConclusionMachine learning methods yield moderate accuracy in predicting glucose tolerance from a wide set of clinical and laboratory variables. A substitution of OGTT does not currently seem to be feasible. An important constraint could be the limited reproducibility of glucose tolerance status during a

  4. 75 FR 29908 - Prothioconazole; Pesticide Tolerances

    Science.gov (United States)

    2010-05-28

    .... The straw numerical value (5 ppm) is matched between the U.S. and Codex. The tolerance definition for... lower (0.07 ppm) than the recommended U.S. group tolerance. The 0.07 ppm value is the current U.S. tolerance value for wheat, but will be replaced by the cereal grain group tolerance. Canada does not...

  5. 78 FR 40027 - Novaluron; Pesticide Tolerances

    Science.gov (United States)

    2013-07-03

    ...). This regulation additionally deletes the time- limited tolerance for strawberry, as that tolerance..., pears, potatoes, strawberries, and tomatoes and utilized estimates for PCT for recently registered uses... deletes the time-limited tolerance for strawberry, as that tolerance expired on December 31, 2011. VI...

  6. Search for heavy lepton resonances decaying to a Z boson and a lepton in proton-proton collisions at √(s)=8 TeV with the ATLAS detector and investigations of radiation tolerant silicon-strip detectors for the high-luminosity LHC upgrade of the ATLAS inner detector

    Energy Technology Data Exchange (ETDEWEB)

    Wiik-Fuchs, Liv

    2017-03-09

    The success of particle physics experiments, like those at the Large Hardon Collider (LHC) at CERN, relies on a worldwide interdisciplinary collaboration in a variety of different fields. This thesis contributes to two vital aspects in this area of research:in the first part of a search for heavy trilepton resonances decaying to a Z boson and an electron or muon is presented, while the second part focusses on research and development of radiation tolerant silicon tracking detectors designed for the upgrade of the ATLAS detector for the future luminosity upgrade of the LHC. The search for trilepton resonances is based on pp collision data taken at a centre-of-mass energy of 8 TeV by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 20.3 fb{sup -1}. To reconstruct the narrow resonance, events with at least three leptons (electrons or muons) with a high-transverse momentum are selected. Two of these leptons are required to be consistent with originating from a Z boson decay. Since no significant excess above Standard Model background predictions is observed, 95% confidence level upper limits on the production cross section of trilepton resonances beyond the Standard Model are derived. The results of this analysis are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 113-176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100-474 GeV are excluded. The second part of this thesis focusses on the development of radiation-tolerant silicon strip detectors for the luminosity upgrade of the ATLAS detector envisaged to commence in the year 2016. This thesis includes the results of several studies which contribute to multiple key aspects required for a successful upgrade of the silicon strip detector of the ATLAS Inner Tracker. Among these are the results of a beam test providing the first comparative results between

  7. Search for heavy lepton resonances decaying to a Z boson and a lepton in proton-proton collisions at √(s)=8 TeV with the ATLAS detector and investigations of radiation tolerant silicon-strip detectors for the high-luminosity LHC upgrade of the ATLAS inner detector

    International Nuclear Information System (INIS)

    Wiik-Fuchs, Liv

    2017-01-01

    The success of particle physics experiments, like those at the Large Hardon Collider (LHC) at CERN, relies on a worldwide interdisciplinary collaboration in a variety of different fields. This thesis contributes to two vital aspects in this area of research:in the first part of a search for heavy trilepton resonances decaying to a Z boson and an electron or muon is presented, while the second part focusses on research and development of radiation tolerant silicon tracking detectors designed for the upgrade of the ATLAS detector for the future luminosity upgrade of the LHC. The search for trilepton resonances is based on pp collision data taken at a centre-of-mass energy of 8 TeV by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 20.3 fb"-"1. To reconstruct the narrow resonance, events with at least three leptons (electrons or muons) with a high-transverse momentum are selected. Two of these leptons are required to be consistent with originating from a Z boson decay. Since no significant excess above Standard Model background predictions is observed, 95% confidence level upper limits on the production cross section of trilepton resonances beyond the Standard Model are derived. The results of this analysis are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 113-176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100-474 GeV are excluded. The second part of this thesis focusses on the development of radiation-tolerant silicon strip detectors for the luminosity upgrade of the ATLAS detector envisaged to commence in the year 2016. This thesis includes the results of several studies which contribute to multiple key aspects required for a successful upgrade of the silicon strip detector of the ATLAS Inner Tracker. Among these are the results of a beam test providing the first comparative results between

  8. Rad-Tolerant, Thermally Stable, High-Speed Fiber-Optic Network for Harsh Environments

    Science.gov (United States)

    Leftwich, Matt; Hull, Tony; Leary, Michael; Leftwich, Marcus

    2013-01-01

    Future NASA destinations will be challenging to get to, have extreme environmental conditions, and may present difficulty in retrieving a spacecraft or its data. Space Photonics is developing a radiation-tolerant (rad-tolerant), high-speed, multi-channel fiber-optic transceiver, associated reconfigurable intelligent node communications architecture, and supporting hardware for intravehicular and ground-based optical networking applications. Data rates approaching 3.2 Gbps per channel will be achieved.

  9. Handbook of radiation effects

    International Nuclear Information System (INIS)

    Holmes-Siedle, A.; Adams, L.

    1993-01-01

    This handbook is intended to serve as a tool for designers of equipment and scientific instruments in cases where they are required to ensure the survival of the equipment in radiation environments. High-technology materials, especially semiconductors and optics, tend to degrade on exposure to radiation in many different ways. Intense high-energy radiation environments are found in nuclear reactors and accelerators, machines for radiation therapy, industrial sterilization, and space. Some engineers have to build equipment which will survive a nuclear explosion from a hostile source. Proper handling of a disaster with radioactive materials requires equipment which depends utterly on semiconductor microelectronics and imaging devices. Thus the technology of radiation-tolerant electronics is an instrument for good social spheres as diverse as disaster planning and the exploration of Mars. In order to design equipment for intense environments like those described above, then degradation from high-energy irradiation must be seen as a basic design parameter. The aim of this handbook is to assist the engineer or student in that thought; to make it possible to write intelligent specifications; to offer some understanding of the complex variety of effects which occur when high-technology components encounter high-energy radiation; and to go thoroughly into the balance of choices of how to alleviate the effects and hence achieve the design aims of the project. Separate abstracts were prepared for 15 chapters of this book

  10. Ionizing radiation, radiation sources, radiation exposure, radiation effects. Pt. 2

    International Nuclear Information System (INIS)

    Schultz, E.

    1985-01-01

    Part 2 deals with radiation exposure due to artificial radiation sources. The article describes X-ray diagnosis complete with an analysis of major methods, nuclear-medical diagnosis, percutaneous radiation therapy, isotope therapy, radiation from industrial generation of nucler energy and other sources of ionizing radiation. In conclusion, the authors attempt to asses total dose, genetically significant dose and various hazards of total radiation exposure by means of a summation of all radiation impacts. (orig./WU) [de

  11. B cells in operational tolerance.

    Science.gov (United States)

    Chesneau, M; Danger, R; Soulillou, J-P; Brouard, S

    2018-02-16

    Transplantation is currently the therapy of choice for endstage organ failure even though it requires long-term immunosuppresive therapy, with its numerous side effects, for acceptance of the transplanted organ. In rare cases however, patients develop operational tolerance, that is, graft survival without immunosuppression. Studies conducted on these patients reveal genetic, phenotypic, and functional signatures. They provide a better understanding of the immunological mechanisms involved in operational tolerance and define biomarkers that could be used to adapt immunosuppressive treatment to the individual, safely reduce immunosuppression doses, and ideally and safely guide immunosuppression withdrawal. This review summarizes studies that suggest a role for B cells as biomarkers of operational tolerance and discusses the use of B cells as a predictive tool for immunologic risk. Copyright © 2018. Published by Elsevier Inc.

  12. Atoms, radiation, and radiation protection

    International Nuclear Information System (INIS)

    Turner, J.E.

    1986-01-01

    This book describes basic atomic and nuclear structure, the physical processes that result in the emission of ionizing radiations, and external and internal radiation protection criteria, standards, and practices from the standpoint of their underlying physical and biological basis. The sources and properties of ionizing radiation-charged particles, photons, and neutrons-and their interactions with matter are discussed in detail. The underlying physical principles of radiation detection and systems for radiation dosimetry are presented. Topics considered include atomic physics and radiation; atomic structure and radiation; the nucleus and nuclear radiation; interaction of heavy charged particles with matter; interaction of beta particles with matter; phenomena associated with charged-particle tracks; interaction of photons with matter; neutrons, fission and criticality; methods of radiation detection; radiation dosimetry; chemical and biological effects of radiation; radiation protection criteria and standards; external radiation protection; and internal dosimetry and radiation protection

  13. Natural radiation

    International Nuclear Information System (INIS)

    Feliciano, Vanusa Maria Delage

    2016-01-01

    Cosmic radiation, as well as cosmogenic radiation, terrestrial radiation, radon and thorium are introduced in this chapter 3. The distribution of natural radiation sources is treated, where the percentage distribution of the contribution relative to exposure to radiation from natural and artificial sources is also included

  14. Exercise (effort) tolerance and factors affecting this tolerance for liquidators of consequences of the ChNPP accident

    International Nuclear Information System (INIS)

    Khomazyuk, I.N.

    1992-01-01

    Physical efficiency and factors affecting it for persons exposed to irradiation (the radiation dose being in the range up to 0.75 Gy) has been studied. 670 participants of liquidating the consequences of ChNPP accident have been examined. Depending on the radiation doses to which the people have been exposed the liquidators have been subdivided into 4 groups: for the 1st group the radiation doses ranging from 0.25 to 0.75 Gy; for the 2nd group the radiation doses ranging from 0.10 to 0.24 Gy; for the 3rd group the radiation doses ranging from 0.05 to 0.10 Gy; for the 4th group the radiation dose being up to 0.05 Gy. The physical load was ensured with veloergometer. The results have made it possible to estimate one of the basic health criterion for liquidators of consequences of ChNPP accident (i.e. exercise (effort) tolerance). No direct relationship of the exercise magnitude and the radiation dose within the range up to 0.75 Gy and the irradiation time have been observed. The correlation of the exercise magnitude with due account to age has been provided. 15 refs.; 2 tabs

  15. Methods to establish flaw tolerances

    International Nuclear Information System (INIS)

    Varga, T.

    1978-01-01

    Three conventional methods used to establish flaw tolerances are compared with new approaches using fracture mechanics. The conventional methods are those based on (a) non-destructive testing methods; (b) fabrication and quality assurance experience; and (c) service and damage experience. Pre-requisites of fracture mechanics methods are outlined, and summaries given of linear elastic mechanics (LEFM) and elastoplastic fracture mechanics (EPFM). The latter includes discussion of C.O.D.(crack opening displacement), the J-integral and equivalent energy. Proposals are made for establishing flaw tolerances. (U.K.)

  16. Tolerating extremism : to what extent should intolerance be tolerated?

    NARCIS (Netherlands)

    Guiora, Amos Neuser

    2013-01-01

    In discussing extremism, the key questions are: to whom is a duty owed and what are the limits of intolerance that are to be tolerated? Answering these questions requires examining limits and rights; analyzing them in the context of extremism is the ‘core’ of this book. While freedom of speech and

  17. Radiation Tolerant Low Power Precision Time Source, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The availability of small, low power atomic clocks is now a reality for ground-based and airborne navigation systems. Kernco's Low Power Precision Time Source...

  18. Reprogrammable Radiation Tolerant Secure Network Access Module, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Communications security (COMSEC) is essential to satellite communications. Its role continues to grow as the available bandwidth expands to meet the ever increasing...

  19. Radiation Tolerant 802.16 Wireless Network, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Exploration of planetary surfaces will require a communication architecture that supports operational capabilities in which fixed and mobile assets on the planetary...

  20. Enhancement of Radiation Tolerance by Interfaces in Nanostructured Metallic Materials

    Science.gov (United States)

    2013-06-05

    these point defects can aggregate to form defect clusters, which can be dislocation loops, voids, or stacking fault tetrahe- dron .[2] High densities of...loops and stacking fault tetrahe- dron [1–4]. Void swelling and He embrittlement may lead to severe degradation of mechanical properties [5,6]. It is of

  1. Normal tissue tolerance to external beam radiation therapy: Ovaries

    International Nuclear Information System (INIS)

    Gross, E.; Champetier, C.; Zaccariotto, A.; Duberge, T.; Guerder, C.; Pointreau, Y.; Ortholan, C.; Chauvet, B.

    2010-01-01

    Clinical situations requiring protections of ovaries are mainly paediatric irradiations and pre-menopausal pelvic irradiations. The main complication of ovarian irradiation is the induced castration. Ovaries are extremely radiosensitive organs with strong interpersonal variations. The castrative effect of irradiation depends mainly on two factors: patient's age and the dose delivered to ovaries. The surgical technique of ovarian transposition allows to minimize the dose received by ovaries by taking them away, out of irradiation fields; the aim is to exclude them from the volume receiving 5 Gy or more, and if possible from those receiving 2 Gy. This technique becomes integrated into a multidisciplinary approach of conservation of fertility for patients exposed to other cytotoxic treatments. (authors)

  2. Radiation Hardened Ethernet PHY and Switch Fabric, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Innoflight will develop a new family of radiation hardened (up to 3 Mrad(Si)), fault-tolerant, high data-rate (up to 8 Gbps), low power Gigabit Ethernet PHY and...

  3. Radiation enteritis

    International Nuclear Information System (INIS)

    Ochsner, S.F.; Head, L.H.

    1973-01-01

    A comprehensive review of radiation enteritis is presented. Experience in clinical radiation therapy has indicated that the small bowel is the segment of the alimentary tract that is most susceptible to radiation damage. (U.S.)

  4. Radiation monitor

    International Nuclear Information System (INIS)

    Pao, C.T.; Green, W.K.

    1978-01-01

    A system for indicating radiation from a radioactive fluid such as a gas wherein simultaneous indications of the activity concentration of radioactivity of the gas, the radiation dose rate and average energy of the radiation are provided

  5. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  6. Radiation sickness

    Science.gov (United States)

    ... exposure to ionizing radiation. There are two main types of radiation: nonionizing and ionizing. Nonionizing radiation comes in the form of light, radio waves, microwaves and radar. These forms usually don't cause tissue damage. ...

  7. Ionizing radiation

    International Nuclear Information System (INIS)

    Kruger, J.

    1989-01-01

    Ionizing radiation results in biological damage that differs from other hazardous substances and is highly dangerous to man. Ionizing radiation cannot be perceived by man's sense organs and the biological damage cannot be detected immediately afterwards (except in very high doses). Every human being is exposed to low doses of radiation. The structure of the atom; sources of ionizing radiation; radiation units; biological effects; norms for radiation protection; and the national control in South Africa are discussed. 1 fig., 5 refs

  8. Tolerance of snakes to hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.

    1996-01-01

    Sensitivity of carotid blood flow to increased gravitational force acting in the head-to-tail direction(+Gz) was studied in diverse species of snakes hypothesized to show adaptive variation of response. Tolerance to increased gravity was measured red as the maximum graded acceleration force at which carotid blood flow ceased and was shown to vary according to gravitational adaptation of species defined by their ecology and behavior. Multiple regression analysis showed that gravitational habitat, but not body length, had a significant effect on Gz tolerance. At the extremes, carotid blood flow decreased in response to increasing G force and approached zero near +1 Gz in aquatic and ground-dwelling species, whereas in climbing species carotid flow was maintained at forces in excess of +2 Gz. Tolerant (arboreal) species were able to withstand hypergravic forces of +2 to +3 Gz for periods up to 1 h without cessation of carotid blood flow or loss of body movement and tongue flicking. Data suggest that the relatively tight skin characteristic of tolerant species provides a natural antigravity suit and is of prime importance in counteracting Gz stress on blood circulation.

  9. Assessing Your Board's Risk Tolerance

    Science.gov (United States)

    Griswold, John S.; Jarvis, William F.

    2014-01-01

    In the wake of the financial crisis, trustees of many endowed nonprofit institutions realized that their portfolio was riskier than they thought and their own ability to tolerate loss wasn't as strong as they imagined. What can board and investment committee members do to improve their ability to assess their--and their institution's--capacity for…

  10. Toleration, Multiculturalism and Mistaken Belief

    Science.gov (United States)

    Standish, Paul

    2006-01-01

    Doubts have been expressed about the virtue of toleration, especially in view of what some have seen as its complicity with a morality of anything goes. More rigorous arguments have been provided by Peter Gardner and Harvey Siegel against the relativism evident in certain versions of multiculturalism and in the new religious studies. This article…

  11. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    1978-01-01

    The Cancergram deals with all aspects of radiation carcinogenesis. The term radiation here includes U-V radiation and the entire electromagnetic spectrum, electron and other charged particle beams, neutrons, and alpha and beta radiation from radioactive substances. Abstracts included concern relationships between radiation and carcinogenesis in humans, experimental induction of tumors in animals by irradiation, studies on the mechanism of radiation carcinogenesis at the cellular level, studies of RBE, dose response or dose threshold in relation to radiation carcinogenesis, and methods and policies for control of radiation exposure in the general population. In general, this Cancergram excludes abstracts on radio-therapy, radiologic diagnosis, radiation pathology, and radiation biology, where these articles have no bearing on radiation carcinogenesis

  12. Radiation hard diamond sensors for future tracking applications

    International Nuclear Information System (INIS)

    Adam, W.; Boer, W. de; Borchi, E.

    2006-01-01

    Progress in experimental particle physics in the coming decade depends crucially upon the ability to carry out experiments in high-radiation areas. In order to perform these complex and expensive experiments, new radiation hard technologies must be developed. This paper discusses the use of diamond detectors in future tracking applications and their survivability in the highest radiation environments. We present results of devices constructed with the newest polycrystalline and single crystal Chemical Vapor Deposition diamond and their tolerance to radiation

  13. Conducting field trials for frost tolerance breeding in cereals.

    Science.gov (United States)

    Cattivelli, Luigi

    2014-01-01

    Cereal species can be damaged by frost either during winter or at flowering stage. Frost tolerance per se is only a part of the mechanisms that allow the plants to survive during winter; winterhardiness also considers other biotic or physical stresses that challenge the plants during the winter season limiting their survival rate. While frost tolerance can also be tested in controlled environments, winterhardiness can be determined only with field evaluations. Post-heading frost damage occurs from radiation frost events in spring during the reproductive stages. A reliable evaluation of winterhardiness or of post-heading frost damage should be carried out with field trials replicated across years and locations to overcome the irregular occurrence of natural conditions which satisfactorily differentiate genotypes. The evaluation of post-heading frost damage requires a specific attention to plant phenology. The extent of frost damage is usually determined with a visual score at the end of the winter.

  14. Physiological determinants of human acute hypoxia tolerance.

    Science.gov (United States)

    2013-11-01

    AbstractIntroduction. We investigated possible physiological determinants of variability in hypoxia tolerance in subjects given a 5-minute normobaric exposure to 25,000 ft equivalent. Physiological tolerance to hypoxia was defined as the magnitude of...

  15. Persistence and drug tolerance in pathogenic yeast

    DEFF Research Database (Denmark)

    Bojsen, Rasmus Kenneth; Regenberg, Birgitte; Folkesson, Sven Anders

    2017-01-01

    In this review, we briefly summarize the current understanding of how fungal pathogens can persist antifungal treatment without heritable resistance mutations by forming tolerant persister cells. Fungal infections tolerant to antifungal treatment have become a major medical problem. One mechanism...

  16. Drought and submergence tolerance in plants

    Energy Technology Data Exchange (ETDEWEB)

    Du, Hewei; Zhou, Yufan; Oksenberg, Nir; Ronald, Pamela

    2017-11-14

    The invention provides methods of genetically modified plants to increase tolerance to drought and/or submergence. The invention additionally provides plants having increased drought and/or submergence tolerance engineered using such methods.

  17. Urbanism, Migration, and Tolerance: A Reassessment.

    Science.gov (United States)

    Wilson, Thomas C.

    1991-01-01

    Urbanism's impact on the personality may be stronger than previously thought. Finds that urban residence has a strong positive effect on tolerance. Migration also promotes tolerance, regardless of the size of the destination community. (DM)

  18. Recent results on CVD diamond radiation sensors

    Science.gov (United States)

    Weilhammer, P.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; v. d. Eijk, R.; van Eijk, B.; Fallou, A.; Fish, D.; Fried, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knopfle, K. T.; Krammer, M.; Manfredi, P. F.; Meier, D.; LeNormand; Pan, L. S.; Pernegger, H.; Pernicka, M.; Plano, R.; Re, V.; Riester, J. L.; Roe, S.; Roff; Rudge, A.; Schieber, M.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; RD 42 Collaboration

    1998-02-01

    CVD diamond radiation sensors are being developed for possible use in trackers in the LHC experiments. The diamond promises to be radiation hard well beyond particle fluences that can be tolerated by Si sensors. Recent results from the RD 42 collaboration on charge collection distance and on radiation hardness of CVD diamond samples will be reported. Measurements with diamond tracking devices, both strip detectors and pixel detectors, will be discussed. Results from beam tests using a diamond strip detector which was read out with fast, 25 ns shaping time, radiation-hard pipeline electronics will be presented.

  19. Radiation sensitivity of integrated circuits Pt. 1

    International Nuclear Information System (INIS)

    Bereczkine Kerenyi, Ilona

    1986-01-01

    The cosmic ray sensitivity of CMOS integrated circuits are overviewed in three parts. The aim is to analyze the effects of ionizing radiation on the degradation of electronic parameters, the effects of the electric state during irradiation, and the radiation hardening of ICs. In this Part 1 a general introduction of the response of semiconductors to cosmic radiation is given, and the radiation tolerance and hardening of small-scale integrated CMOS ICs is analyzed in detail. The devices include various basic inverters and simple gate ICs. (R.P.)

  20. 75 FR 17566 - Flutolanil; Pesticide Tolerances

    Science.gov (United States)

    2010-04-07

    ... ppm, and the greater tolerance value is needed to accommodate indirect residues from soybean..., and soybean hay at 2.5 ppm are being revoked since the same tolerance values are being established...; Pesticide Tolerances AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This...

  1. 77 FR 49732 - Cyprodinil; Pesticide Tolerances

    Science.gov (United States)

    2012-08-17

    .../puree (1x) and lemon/lime juice (1x) were used to modify the tolerance values. iii. Cancer. Based on the... the tolerance necessitate a higher value. Additionally, Codex has an established MRL on grape at 3 ppm...; Pesticide Tolerances AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This...

  2. 15 CFR 750.11 - Shipping tolerances.

    Science.gov (United States)

    2010-01-01

    ... in the ECCN applicable to your item reads “ $ value” or “in $ value”, there is no shipping tolerance... is no shipping tolerance with respect to the number of units. However, the value of all of your... shipping tolerance on this license because the items are controlled by an ECCN where “$ value” is the...

  3. 78 FR 18511 - Thiamethoxam; Pesticide Tolerances

    Science.gov (United States)

    2013-03-27

    ... Health Risk Assessment of New Uses on Strawberry, Pistachio, and Citrus; New Tolerance for Tea; and... Uses on Strawberry, Pistachio, and Citrus; New Tolerance for Tea; and Revised PHI and Tolerance for... ``Clothianidin--Aggregate Human Health Risk Assessment of New Uses on Strawberry, Pistachio, and Citrus; New...

  4. 77 FR 28493 - Propylene Oxide; Tolerance Actions

    Science.gov (United States)

    2012-05-15

    .... SUMMARY: EPA is establishing the tree nut crop group tolerance and separate tolerances on pistachio and...; nut, tree, group 14; and pistachio; and in 40 CFR 180.491(a)(2) tolerances for propylene chlorohydrin at 10.0 ppm on nut, pine; nut, tree, group 14; and pistachio. Also, in accordance with current Agency...

  5. 75 FR 26673 - Clethodim; Pesticide Tolerances

    Science.gov (United States)

    2010-05-12

    ... regulation establishes tolerances for residues of clethodim in or on the raw agricultural commodity artichoke... clethodim, in or on the raw agricultural commodity artichoke, globe at 1.3 parts per million (ppm... bushberry subgroup 13-07B tolerance from 3.0 ppm to 0.20 ppm and the globe artichoke tolerance from 1.3 ppm...

  6. Selection and characterisation of high ethanol tolerant ...

    African Journals Online (AJOL)

    15% ethanol tolerance. High level ethanol tolerant Saccharomyces yeast, Orc 6, was investigated for its potential application in ethanologenic fermentations. Data presented in this study revealed that Orc 6 yeast isolate tolerated osmotic stress above 12% (w/v) sorbitol and 15% (w/v) sucrose equivalent of osmotic pressure ...

  7. Zero Tolerance: Advantages and Disadvantages. Research Brief

    Science.gov (United States)

    Walker, Karen

    2009-01-01

    What are the positives and negatives of zero tolerance? What should be considered when examining a school's program? Although there are no definitive definitions of zero tolerance, two commonly used ones are as follows: "Zero tolerance means that a school will automatically and severely punish a student for a variety of infractions" (American Bar…

  8. What is Fault Tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Frei, C. W.; Kraus, K.

    2000-01-01

    Faults in automated processes will often cause undesired reactions and shut-down of a controlled plant, and the consequences could be damage to the plant, to personnel or the environment. Fault-tolerant control is the synonym for a set of recent techniques that were developed to increase plant...... availability and reduce the risk of safety hazards. Its aim is to prevent that simple faults develop into serious failure. Fault-tolerant control merges several disciplines to achieve this goal, including on-line fault diagnosis, automatic condition assessment and calculation of remedial actions when a fault...... is detected. The envelope of the possible remedial actions is wide. This paper introduces tools to analyze and explore structure and other fundamental properties of an automated system such that any redundancy in the process can be fully utilized to enhance safety and a availability....

  9. Fault Tolerant External Memory Algorithms

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Brodal, Gerth Stølting; Mølhave, Thomas

    2009-01-01

    Algorithms dealing with massive data sets are usually designed for I/O-efficiency, often captured by the I/O model by Aggarwal and Vitter. Another aspect of dealing with massive data is how to deal with memory faults, e.g. captured by the adversary based faulty memory RAM by Finocchi and Italiano....... However, current fault tolerant algorithms do not scale beyond the internal memory. In this paper we investigate for the first time the connection between I/O-efficiency in the I/O model and fault tolerance in the faulty memory RAM, and we assume that both memory and disk are unreliable. We show a lower...... bound on the number of I/Os required for any deterministic dictionary that is resilient to memory faults. We design a static and a dynamic deterministic dictionary with optimal query performance as well as an optimal sorting algorithm and an optimal priority queue. Finally, we consider scenarios where...

  10. Copper tolerance of Trichoderma species

    Directory of Open Access Journals (Sweden)

    Jovičić-Petrović Jelena

    2014-01-01

    Full Text Available Some Trichoderma strains can persist in ecosystems with high concentrations of heavy metals. The aim of this research was to examine the variability of Trichoderma strains isolated from different ecosystems, based on their morphological properties and restriction analysis of ITS fragments. The fungal growth was tested on potato dextrose agar, amended with Cu(II concentrations ranging from 0.25 to 10 mmol/l, in order to identify copper-resistant strains. The results indicate that some isolated strains of Trichoderma sp. show tolerance to higher copper concentrations. Further research to examine the ability of copper bioaccumulation by tolerant Trichoderma strains is needed. [Projekat Ministarstva nauke Republike Srbije, br. TR 31080 i br. III 43010

  11. A damage-tolerant glass.

    Science.gov (United States)

    Demetriou, Marios D; Launey, Maximilien E; Garrett, Glenn; Schramm, Joseph P; Hofmann, Douglas C; Johnson, William L; Ritchie, Robert O

    2011-02-01

    Owing to a lack of microstructure, glassy materials are inherently strong but brittle, and often demonstrate extreme sensitivity to flaws. Accordingly, their macroscopic failure is often not initiated by plastic yielding, and almost always terminated by brittle fracture. Unlike conventional brittle glasses, metallic glasses are generally capable of limited plastic yielding by shear-band sliding in the presence of a flaw, and thus exhibit toughness-strength relationships that lie between those of brittle ceramics and marginally tough metals. Here, a bulk glassy palladium alloy is introduced, demonstrating an unusual capacity for shielding an opening crack accommodated by an extensive shear-band sliding process, which promotes a fracture toughness comparable to those of the toughest materials known. This result demonstrates that the combination of toughness and strength (that is, damage tolerance) accessible to amorphous materials extends beyond the benchmark ranges established by the toughest and strongest materials known, thereby pushing the envelope of damage tolerance accessible to a structural metal.

  12. Modelling Accident Tolerant Fuel Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Hales, Jason Dean [Idaho National Laboratory; Gamble, Kyle Allan Lawrence [Idaho National Laboratory

    2016-05-01

    The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. The United States Department of Energy (DOE) through its Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is a three-year project to perform research on two accident tolerant concepts. The final outcome of the ATF HIP will be an in-depth report to the DOE Advanced Fuels Campaign (AFC) giving a recommendation on whether either of the two concepts should be included in their lead test assembly scheduled for placement into a commercial reactor in 2022. The two ATF concepts under investigation in the HIP are uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (Idaho National Laboratory, Los Alamos National Laboratory, and Argonne National Laboratory), a comprehensive multiscale approach to modeling is being used that includes atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. Model development and fuel performance analysis are critical since a full suite of experimental studies will not be complete before AFC must prioritize concepts for focused development. In this paper, we present simulations of the two proposed accident tolerance fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. Sensitivity analyses are completed using Sandia National Laboratories’ Dakota software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). We also outline the multiscale modelling approach being employed. Considerable additional work is required prior to preparing the recommendation report for the Advanced

  13. Historical overview of immunological tolerance.

    Science.gov (United States)

    Schwartz, Ronald H

    2012-04-01

    A fundamental property of the immune system is its ability to mediate self-defense with a minimal amount of collateral damage to the host. The system uses several different mechanisms to achieve this goal, which is collectively referred to as the "process of immunological tolerance." This article provides an introductory historical overview to these various mechanisms, which are discussed in greater detail throughout this collection, and then briefly describes what happens when this process fails, a state referred to as "autoimmunity."

  14. SALT TOLERANCE OF CROP PLANTS

    OpenAIRE

    Hamdia, M. A; Shaddad, M. A. K.

    2010-01-01

    Several environmental factors adversely affect plant growth and development and final yield performance of a crop. Drought, salinity, nutrient imbalances (including mineral toxicities and deficiencies) and extremes of temperature are among the major environmental constraints to crop productivity worldwide. Development of crop plants with stress tolerance, however, requires, among others, knowledge of the physiological mechanisms and genetic controls of the contributing traits at different pla...

  15. Fault Tolerant Wind Farm Control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2013-01-01

    In the recent years the wind turbine industry has focused on optimizing the cost of energy. One of the important factors in this is to increase reliability of the wind turbines. Advanced fault detection, isolation and accommodation are important tools in this process. Clearly most faults are deal...... scenarios. This benchmark model is used in an international competition dealing with Wind Farm fault detection and isolation and fault tolerant control....

  16. Stress tolerance of soil fungal communities from native Atlantic forests, reforestations, and a sand mining degraded area.

    Science.gov (United States)

    Ferreira, Paulo C; Pupin, Breno; Rangel, Drauzio E N

    2018-06-01

    Microorganisms are essential to the functionality of the soil, particularly in organic matter decomposition and nutrient cycling, which regulate plant productivity and shape the soil structure. However, biotic and abiotic stresses greatly disrupt soil fungal communities and, thereby, disturb the ecosystem. This study quantified seasonal tolerances to UV-B radiation and heat of fungal communities, which could be cultured, found in soil from two native Atlantic forest fragments called F1 and F2, five reforested areas (RA) planted in 1994, 1997, 2004, 2007, and 2009 with native species of the Atlantic forest, and one sand mining degraded soil (SMDS). The cold activity of the soil fungal communities (FC) from the eight different areas was also studied. Higher tolerance to UV-B radiation and heat was found in the FC from the SMDS and the 2009RA, where the incidence of heat and UV radiation from sun was more intense, which caused selection for fungal taxa that were more UV-B and heat tolerant in those areas. Conversely, the FC from the native forests and older reforested sites were very susceptible to heat and UV-B radiation. The cold activity of the soil FC from different areas of the study showed an erratic pattern of responses among the sampling sites. Little difference in tolerance to UV-B radiation and heat was found among the FC of soil samples collected in different seasons; in general soil FC collected in winter were less tolerant to UV-B radiation, but not for heat. In conclusion, FC from SMDS soil that receive intense heat and UV radiation, as well as with low nutrient availability, were more tolerant to both UV-B radiation and heat. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  17. SALT TOLERANCE OF CROP PLANTS

    Directory of Open Access Journals (Sweden)

    Hamdia, M. A

    2010-09-01

    Full Text Available Several environmental factors adversely affect plant growth and development and final yield performance of a crop. Drought, salinity, nutrient imbalances (including mineral toxicities and deficiencies and extremes of temperature are among the major environmental constraints to crop productivity worldwide. Development of crop plants with stress tolerance, however, requires, among others, knowledge of the physiological mechanisms and genetic controls of the contributing traits at different plant developmental stages. In the past 2 decades, biotechnology research has provided considerable insights into the mechanism of biotic stress tolerance in plants at the molecular level. Furthermore, different abiotic stress factors may provoke osmotic stress, oxidative stress and protein denaturation in plants, which lead to similar cellular adaptive responses such as accumulation of compatible solutes, induction of stress proteins, and acceleration of reactive oxygen species scavenging systems. Recently, the authores try to improve plant tolerance to salinity injury through either chemical treatments (plant hormones, minerals, amino acids, quaternary ammonium compounds, polyamines and vitamins or biofertilizers treatments (Asymbiotic nitrogen-fixing bacteria, symbiotic nitrogen-fixing bacteria and mycorrhiza or enhanced a process used naturally by plants to minimise the movement of Na+ to the shoot, using genetic modification to amplify the process, helping plants to do what they already do - but to do it much better."

  18. Tolerance of Snakes to Hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.

    1994-01-01

    Sensitivity of carotid blood flow to +Gz (head-to-tail) acceleration was studied in six species of snakes hypothesized to show varied adaptive cardiovascular responses to gravity. Blood flow in the proximal carotid artery was measured in 15 snakes before, during and following stepwise increments of +0.25Gz force produced on a 2.4 m diameter centrifuge. During centrifugation each snake was confined to a straight position within an individually- fitted acrylic tube with the head facing the center of rotation. We measured the centrifugal force at the tail of the snake in order to quantify the maximum intensity of force gradient promoting antero-posterior pooling of blood. Tolerance to increased gravity was quantified as the acceleration force at which carotid blood flow ceased. This parameter varied according to the gravitational adaptation of species defined by their ecology and behavior. At the extremes, carotid blood flow decreased in response to increasing gravity and approached zero near +1Gz in aquatic and ground-dwelling species, whereas in climbing species carotid flow was maintained at forces in excess of +2Gz. Surprisingly, tolerant (arboreal) species withstood hypergravic forces of +2 to +3 G. for periods up to 1 h without cessation of carotid blood flow or apparent loss of consciousness. Data suggest that relatively tight skin of the tolerant species provides a natural antigravity suit which is of prime importance in counteracting Gz stress on blood circulation.

  19. Radiation practices and radiation measurements

    International Nuclear Information System (INIS)

    2008-03-01

    The guide presents the principal requirements on accuracy of radiation measurements and on the approval, calibration and operating condition inspections of radiation meters, together with requirements for dosimetric services measuring the individual radiation doses of workers engaged in radiation work (approved dosimetric services). The Guide also sets out the definitions of quantities and units used in radiation measurements. The radiation protection quantities used for assessing the harmful effects of radiation and for expressing the maximum values for radiation exposure (equivalent dose and effective dose) are set out in Guide ST 7.2. This Guide concerns measurements of ionizing radiation involved in radiation practices, the results of which are used for determining the radiation exposure of workers engaged in radiation work and members of the public, and of patients subject to the use of radiation in health services, or upon the basis of which compliance with safety requirements of appliances currently in use and of their premises of use or of the workplaces of workers is ensured. The Guide also concerns measurements of the radon concentration of inhaled air in both workplaces and dwellings. The Guide does not apply to determining the radiation exposure of aircrews, determination of exposure caused by internal radiation, or measurements made to protect the public in the event of, or in preparation for abnormal radiation conditions

  20. Ultraviolet radiation and cyanobacteria.

    Science.gov (United States)

    Rastogi, Rajesh Prasad; Sinha, Rajeshwar P; Moh, Sang Hyun; Lee, Taek Kyun; Kottuparambil, Sreejith; Kim, Youn-Jung; Rhee, Jae-Sung; Choi, Eun-Mi; Brown, Murray T; Häder, Donat-Peter; Han, Taejun

    2014-12-01

    Cyanobacteria are the dominant photosynthetic prokaryotes from an ecological, economical, or evolutionary perspective, and depend on solar energy to conduct their normal life processes. However, the marked increase in solar ultraviolet radiation (UVR) caused by the continuous depletion of the stratospheric ozone shield has fueled serious concerns about the ecological consequences for all living organisms, including cyanobacteria. UV-B radiation can damage cellular DNA and several physiological and biochemical processes in cyanobacterial cells, either directly, through its interaction with certain biomolecules that absorb in the UV range, or indirectly, with the oxidative stress exerted by reactive oxygen species. However, cyanobacteria have a long history of survival on Earth, and they predate the existence of the present ozone shield. To withstand the detrimental effects of solar UVR, these prokaryotes have evolved several lines of defense and various tolerance mechanisms, including avoidance, antioxidant production, DNA repair, protein resynthesis, programmed cell death, and the synthesis of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. This study critically reviews the current information on the effects of UVR on several physiological and biochemical processes of cyanobacteria and the various tolerance mechanisms they have developed. Genomic insights into the biosynthesis of MAAs and scytonemin and recent advances in our understanding of the roles of exopolysaccharides and heat shock proteins in photoprotection are also discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Fault-tolerant architecture: Evaluation methodology

    International Nuclear Information System (INIS)

    Battle, R.E.; Kisner, R.A.

    1992-08-01

    The design and reliability of four fault-tolerant architectures that may be used in nuclear power plant control systems were evaluated. Two architectures are variations of triple-modular-redundant (TMR) systems, and two are variations of dual redundant systems. The evaluation includes a review of methods of implementing fault-tolerant control, the importance of automatic recovery from failures, methods of self-testing diagnostics, block diagrams of typical fault-tolerant controllers, review of fault-tolerant controllers operating in nuclear power plants, and fault tree reliability analyses of fault-tolerant systems

  2. Infrared Radiation and Blackbody Radiation

    OpenAIRE

    2005-01-01

    tut present graph Tutorial Presentation Graph Interactive Media Element This interactive tutorial covers the following: How infrared radiation was discovered., The regions of infrared radiation and their relations to temperature., The nature of blackbody radiation and Planck's radiation law., The relationship between temperature and the power emitted by radiation.The interactions in this tutorial include clicking to reveal new information, and questions that help students...

  3. Radiation therapy of thoracic and abdominal tumors

    International Nuclear Information System (INIS)

    LaRue, S.M.; Gillette, S.M.; Poulson, J.M.

    1995-01-01

    Until recently, radiotherapy of thoracic and abdominal tumors in animals has been limited. However, the availability of computerized tomography and other imaging techniques to aid in determining the extent of tumor, an increase in knowledge of dose tolerance of regional organs, the availability of isocentrically mounted megavoltage machines, and the willingness of patients to pursue more aggressive treatment is making radiation therapy of tumors in these regions far more common. Tumor remission has been reported after radiation therapy of thymomas. Radiation therapy has been used to treat mediastinal lymphoma refractory to chemotherapy, and may be beneficial as part of the initial treatment regimen for this disease. Chemodectomas are responsive to radiation therapy in human patients, and favorable response has also been reported in dogs. Although primary lung tumors in dogs are rare, in some cases radiation therapy could be a useful primary or adjunctive therapy. Lung is the dose-limiting organ in the thorax. Bladder and urethral tumors in dogs have been treated using intraoperative and external-beam radiation therapy combined with chemotherapy. These tumors are difficult to control locally with surgery alone, although the optimal method of combining treatment modalities has not been established. Local control of malignant perianal tumors is also difficult to achieve with surgery alone, and radiation therapy should be used. Intraoperative radiation therapy combined with external-beam radiation therapy has been used for the management of metastatic carcinoma to the sublumbar lymph nodes. Tolerance of retroperitoneal tissues may be decreased by disease or surgical manipulation

  4. Radiation-induced myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Gaenshirt, H [Heidelberg Univ. (F.R. Germany). Neurologische Klinik

    1975-10-01

    12 cases of radiation-induced myelopathy after /sup 60/Co teletherapy are reported on. Among these were 10 thoracal lesions, one cerviothoracal lesion, and one lesion of the medulla oblongata. In 9 cases, Hodgkin's disease had been the primary disease, tow patients had been irradiated because of suspected vertebral metastases of cancer of the breast, and one patient had suffered from a glomus tumour of the petrous bone. The spinal doses had exceeded the tolerance doses recommended in the relevant literature. There was no close correlation between the radiation dose and the course of the disease. The latency periods between the end of the radiotherapy and the onset of the neurological symptons varied from 6 to 16 mouths and were very constant in 7 cases with 6 to 9 months. The segmental height of the lesion corresponded to the level of irradiation. The presenting symptons of radiation-induced myelopathy are buruing dysaesthesias and Brown-Sequard's paralysis which may develop into transverse lesion of the cord with paraplegia still accompanied by dissociated perception disorders. The disease developed intermittently. Disturbances of the bladder function are frequent. The fluid is normal in most cases. Myelographic examinations were made in 8 cases. 3 cases developed into stationary cases exhibiting. Brown-Sequard syndrome, while 9 patients developed transverse lesion of the cord with paraplegia. 3 patients have died; antopsy findings are given for two of these. In the pathogenesis of radiation-induced myelopathy, the vascular factor is assumed to be of decisive importance.

  5. IRON-TOLERANT CYANOBACTERIA: IMPLICATIONS FOR ASTROBIOLOGY

    Science.gov (United States)

    Brown, Igor I.; Allen, Carlton C.; Mummey, Daniel L.; Sarkisova, Svetlana A.; McKay, David S.

    2006-01-01

    The review is dedicated to the new group of extremophiles - iron tolerant cyanobacteria. The authors have analyzed earlier published articles about the ecology of iron tolerant cyanobacteria and their diversity. It was concluded that contemporary iron depositing hot springs might be considered as relative analogs of Precambrian environment. The authors have concluded that the diversity of iron-tolerant cyanobacteria is understudied. The authors also analyzed published data about the physiological peculiarities of iron tolerant cyanobacteria. They made the conclusion that iron tolerant cyanobacteria may oxidize reduced iron through the photosystem of cyanobacteria. The involvement of both Reaction Centers 1 and 2 is also discussed. The conclusion that iron tolerant protocyanobacteria could be involved in banded iron formations generation is also proposed. The possible mechanism of the transition from an oxygenic photosynthesis to an oxygenic one is also discussed. In the final part of the review the authors consider the possible implications of iron tolerant cyanobacteria for astrobiology.

  6. Clinical and morphological aspects of radiation pneumonitis

    International Nuclear Information System (INIS)

    Schuh, D.; Eberhardt, H.J.

    1983-01-01

    Individually different radiation tolerance with relative dose dependence of the radioreaction could be revealed. Various radiation independent diseases of the lungs are predisposing factors of radiogenic pneumonitis. Even severe diffuse pneumonias can be clinically and radiologically asymptomatic. An enhanced toxic effect of combined cytostatic and radiotherapy could be demonstrated once more. Obviously irradiation causes lasting damage of the pulmonary tissue, being a changed but stereotype reaction to different irritations

  7. Radiation safety

    International Nuclear Information System (INIS)

    Jain, Priyanka

    2014-01-01

    The use of radiation sources is a privilege; in order to retain the privilege, all persons who use sources of radiation must follow policies and procedures for their safe and legal use. The purpose of this poster is to describe the policies and procedures of the Radiation Protection Program. Specific conditions of radiation safety require the establishment of peer committees to evaluate proposals for the use of radionuclides, the appointment of a radiation safety officer, and the implementation of a radiation safety program. In addition, the University and Medical Centre administrations have determined that the use of radiation producing machines and non-ionizing radiation sources shall be included in the radiation safety program. These Radiation Safety policies are intended to ensure that such use is in accordance with applicable State and Federal regulations and accepted standards as directed towards the protection of health and the minimization of hazard to life or property. It is the policy that all activities involving ionizing radiation or radiation emitting devices be conducted so as to keep hazards from radiation to a minimum. Persons involved in these activities are expected to comply fully with the Canadian Nuclear Safety Act and all it. The risk of prosecution by the Department of Health and Community Services exists if compliance with all applicable legislation is not fulfilled. (author)

  8. The failure-tolerant leader.

    Science.gov (United States)

    Farson, Richard; Keyes, Ralph

    2002-08-01

    "The fastest way to succeed," IBM's Thomas Watson, Sr., once said, "is to double your failure rate." In recent years, more and more executives have embraced Watson's point of view, coming to understand what innovators have always known: Failure is a prerequisite to invention. But while companies may grasp the value of making mistakes at the level of corporate practices, they have a harder time accepting the idea at the personal level. People are afraid to fail, and corporate culture reinforces that fear. In this article, psychologist and former Harvard Business School professor Richard Farson and coauthor Ralph Keyes discuss how companies can reduce the fear of miscues. What's crucial is the presence of failure-tolerant leaders--executives who, through their words and actions, help employees overcome their anxieties about making mistakes and, in the process, create a culture of intelligent risk-taking that leads to sustained innovation. Such leaders don't just accept productive failure, they promote it. Drawing from their research in business, politics, sports, and science, the authors identify common practices among failure-tolerant leaders. These leaders break down the social and bureaucratic barriers that separate them from their followers. They engage at a personal level with the people they lead. They avoid giving either praise or criticism, preferring to take a nonjudgmental, analytical posture as they interact with staff. They openly admit their own mistakes rather than trying to cover them up or shifting the blame. And they try to root out the destructive competitiveness built into most organizations. Above all else, failure-tolerant leaders push people to see beyond traditional definitions of success and failure. They know that as long as a person views failure as the opposite of success, rather than its complement, he or she will never be able to take the risks necessary for innovation.

  9. Radiation safety

    International Nuclear Information System (INIS)

    Woods, D.A.

    1982-01-01

    Sections include: dose units, dose limits, dose rate, potential hazards of ionizing radiations, control of internal and external radiation exposure, personal dosemeters, monitoring programs and transport of radioactive material (packaging and shielding)

  10. Synchrotron radiation

    International Nuclear Information System (INIS)

    Hallmeier, K.H.; Meisel, A.; Ranft, J.

    1982-01-01

    The physical background and the properties of synchrotron radiation are described. The radiation offers many useful applications in the fields of spectroscopy and structural investigations. Some examples are given

  11. Noise tolerant spatiotemporal chaos computing.

    Science.gov (United States)

    Kia, Behnam; Kia, Sarvenaz; Lindner, John F; Sinha, Sudeshna; Ditto, William L

    2014-12-01

    We introduce and design a noise tolerant chaos computing system based on a coupled map lattice (CML) and the noise reduction capabilities inherent in coupled dynamical systems. The resulting spatiotemporal chaos computing system is more robust to noise than a single map chaos computing system. In this CML based approach to computing, under the coupled dynamics, the local noise from different nodes of the lattice diffuses across the lattice, and it attenuates each other's effects, resulting in a system with less noise content and a more robust chaos computing architecture.

  12. Anhydrobiosis and Freezing-Tolerance

    DEFF Research Database (Denmark)

    McGill, Lorraine; Shannon, Adam; Pisani, Davide

    2015-01-01

    Anhydrobiotic animals can survive the loss of both free and bound water from their cells. While in this state they are also resistant to freezing. This physiology adapts anhydrobiotes to harsh environments and it aids their dispersal. Panagrolaimus davidi, a bacterial feeding anhydrobiotic nematode...... Panagrolaimus strains from tropical, temperate, continental and polar habitats and we analysed their phylogenetic relationships. We found that several other Panagrolaimus isolates can also survive freezing when fully hydrated and that tissue extracts from these freezing-tolerant nematodes can inhibit the growth...

  13. Radiation monitoring

    International Nuclear Information System (INIS)

    Larsson, L.Eh.; B'yuli, D.K.; Karmikel, Dzh.Kh.E.

    1985-01-01

    Recommendations on radiation monitoring of personnel, used medical ionizing radiation source, are given. The necessity to carry out radiation monitoring of situation at medical personnel's positions and personnel dosimetry is marked. It is convenient to subdivide radiation monitoring into 3 types: usual, surgical and special. Usual monitoring is connected with current work; surgical monitoring is carried out to receive information during a concrete operation; special monitoring is used to detect possible deviation from standard conditions of work or when suspecting them

  14. Medical radiation

    International Nuclear Information System (INIS)

    1992-01-01

    This leaflet in the At-a-Glance Series describes the medical use of X-rays, how X-rays help in diagnosis, radiation protection of the patient, staff protection, how radioactive materials in nuclear medicine examinations help in diagnosis and the use of radiation in radiotherapy. Magnetic resonance imaging, a diagnostic technique involving no ionizing radiation, is also briefly examined. The role of the NRPB in the medical use of radiation is outlined. (UK)

  15. Tolerance of canine portal vein anastomosis to intraoperative X-irradiation

    International Nuclear Information System (INIS)

    Ohara, K.; Takeshima, T.

    1987-01-01

    Tolerance of surgical portal vein anatomosis to intraoperative radiation therapy (IORT) was studied in dogs after single doses of zero, 10, 20 and 40 Gy (290 kVp X-rays). Portal venography was performed prior to IORT and before sacrificing. The dogs were sacrificed 3 and 12 months respectively after irradiation. Portal venography revealed no radiation induced anastomotic stenosis. Autopys disclosed macroscopic periportal fibrosis in all dogs, independent of radiation dose and observation periods. Microscopically, the three tunicas of the vein did not show any pathological changes after any dose level. (orig.)

  16. Ionizing radiation

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1982-01-01

    The subject is discussed under the headings: characteristics of ionizing radiations; biological effects; comparison of radiation and other industrial risks; principles of protection; cost-benefit analysis; dose limits; the control and monitoring of radiation; reference levels; emergency reference levels. (U.K.)

  17. Radiation watchdog

    International Nuclear Information System (INIS)

    Manning, R.

    1984-01-01

    Designated by WHO as a Collaborating Centre, the Radiation Emergency Assistance Center/Training Site (REAC/TS) in Oak Ridge, Tennessee provides assistance to all countries of the Americas in radiation accidents including human contamination or overexposure. It also conducts courses in radiation emergency response for health professionals from throughout the world

  18. Radiation hazards

    International Nuclear Information System (INIS)

    Rausch, L.

    1979-01-01

    On a scientific basis and with the aid of realistic examples, the author gives a popular introduction to an understanding and judgment of the public discussion over radiation hazards: Uses and hazards of X-ray examinations, biological radiation effects, civilisation risks in comparison, origins and explanation of radiation protection regulations. (orig.) [de

  19. The peer effect on pain tolerance.

    Science.gov (United States)

    Engebretsen, Solveig; Frigessi, Arnoldo; Engø-Monsen, Kenth; Furberg, Anne-Sofie; Stubhaug, Audun; de Blasio, Birgitte Freiesleben; Nielsen, Christopher Sivert

    2018-05-19

    Twin studies have found that approximately half of the variance in pain tolerance can be explained by genetic factors, while shared family environment has a negligible effect. Hence, a large proportion of the variance in pain tolerance is explained by the (non-shared) unique environment. The social environment beyond the family is a potential candidate for explaining some of the variance in pain tolerance. Numerous individual traits have previously shown to be associated with friendship ties. In this study, we investigate whether pain tolerance is associated with friendship ties. We study the friendship effect on pain tolerance by considering data from the Tromsø Study: Fit Futures I, which contains pain tolerance measurements and social network information for adolescents attending first year of upper secondary school in the Tromsø area in Northern Norway. Pain tolerance was measured with the cold-pressor test (primary outcome), contact heat and pressure algometry. We analyse the data by using statistical methods from social network analysis. Specifically, we compute pairwise correlations in pain tolerance among friends. We also fit network autocorrelation models to the data, where the pain tolerance of an individual is explained by (among other factors) the average pain tolerance of the individual's friends. We find a significant and positive relationship between the pain tolerance of an individual and the pain tolerance of their friends. The estimated effect is that for every 1 s increase in friends' average cold-pressor tolerance time, the expected cold-pressor pain tolerance of the individual increases by 0.21 s (p-value: 0.0049, sample size n=997). This estimated effect is controlled for sex. The friendship effect remains significant when controlling for potential confounders such as lifestyle factors and test sequence among the students. Further investigating the role of sex on this friendship effect, we only find a significant peer effect of male friends

  20. Future directions in radiation oncology

    International Nuclear Information System (INIS)

    Peters, L.

    1996-01-01

    Full text: Cancer treatment has evolved progressively over the years as a joint result of improvements in technology and better understanding of the biological responses of neoplastic and normal cells to cytotoxic agents. Although major therapeutic 'breakthroughs' are unlikely absent the discovery of exploitable fundamental differences between cancer cells and their normal homologs, further incremental improvements in cancer treatment results can confidently be expected as we apply existing knowledge better and take advantage of new research insights. Areas in which I can foresee significant improvements (in approximate chronological order) are as follows: better physical radiation dose distributions; more effective radiation and chemoradiation protocols based on radiobiological principles; more rational use of radiation adjuvants based on biologic criteria; use of novel targets and vectors for systemic radionuclide therapy; use of genetic markers of radiosensitivity to determine radiation dose tolerances; and use of radiation as a modulator of therapeutic gene expression. Radiation research has contributed greatly to the efficacy of radiation oncology as it is now practised but has even greater potential for the future

  1. Microbial stress tolerance for biofuels. Systems biology

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zonglin Lewis (ed.) [National Center for Agricultural Utilization Research, USDA-ARS, Peoria, IL (United States)

    2012-07-01

    The development of sustainable and renewable biofuels is attracting growing interest. It is vital to develop robust microbial strains for biocatalysts that are able to function under multiple stress conditions. This Microbiology Monograph provides an overview of methods for studying microbial stress tolerance for biofuels applications using a systems biology approach. Topics covered range from mechanisms to methodology for yeast and bacteria, including the genomics of yeast tolerance and detoxification; genetics and regulation of glycogen and trehalose metabolism; programmed cell death; high gravity fermentations; ethanol tolerance; improving biomass sugar utilization by engineered Saccharomyces; the genomics on tolerance of Zymomonas mobilis; microbial solvent tolerance; control of stress tolerance in bacterial host organisms; metabolomics for ethanologenic yeast; automated proteomics work cell systems for strain improvement; and unification of gene expression data for comparable analyses under stress conditions. (orig.)

  2. Ionizing radiations

    International Nuclear Information System (INIS)

    Newton, W.

    1984-01-01

    The purpose of this article is to simplify some of the relevant points of legislation, biological effects and protection for the benefit of the occupational health nurse not familiar with the nuclear industries. The subject is dealt with under the following headings; Understanding atoms. What is meant by ionizing radiation. Types of ionizing radiation. Effects of radiation: long and short term somatic effects, genetic effects. Control of radiation: occupational exposure, women of reproductive age, medical aspects, principles of control. The occupational health nurse's role. Emergency arrangements: national arrangements for incidents involving radiation, action to be taken by the nurse. Decontamination procedures: external and internal contamination. (U.K.)

  3. Radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redmayne, I.

    1986-05-21

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed.

  4. Radiation imaging

    International Nuclear Information System (INIS)

    Redmayne, Ian.

    1986-01-01

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed. (author)

  5. Gigarad-tolerant power switches and memory elements

    International Nuclear Information System (INIS)

    Joyner, W.T.; Becknell, G.F.; Donelson, J.M.A.

    1987-01-01

    A new class of silicon devices operating without p-n junctions has been studied for radiation hardness. The electric field in these devices is uniform over most of the device, thus causing high-voltage breakdown to increase with electrode spacing. Deep acceptor levels are created in the silicon by diffusing gold atoms into the lattice, or by electron radiation. These acceptor levels, near the center of the band gap, trap out electrons so that the low resistivity of the n-type doped wafer can be raised to intrinsic resistivity. Switching between a high-resistivity state at low currents and a low-resistivity state at high currents occurs at a definite threshold voltage, exhibiting characteristics similar to silicon-controlled rectifiers. Compensating 0.1 ohm-meter (10 ohm-cm) silicon wafers requires electron fluxes of 10 23 electrons per square meter (10 19 electrons per square centimeter). Experiments demonstrating gamma tolerance to 1 Gigarad(Si) are described. Calculations for maximum tolerable neutron fluence are shown, and a phenomenological explanation for these results is presented

  6. Development of radiation hardened pixel sensors for charged particle detection

    CERN Document Server

    Koziel, Michal

    2014-01-01

    CMOS Pixel Sensors are being developed since a few years to equip vertex detectors for future high-energy physics experiments with the crucial advantages of a low material budget and low production costs. The features simultaneously required are a short readout time, high granularity and high tolerance to radiation. This thesis mainly focuses on the radiation tolerance studies. To achieve the targeted readout time (tens of microseconds), the sensor pixel readout was organized in parallel columns restricting in addition the readout to pixels that had collected the signal charge. The pixels became then more complex, and consequently more sensitive to radiation. Different in-pixel architectures were studied and it was concluded that the tolerance to ionizing radiation was limited to 300 krad with the 0.35- m fabrication process currently used, while the targeted value was several Mrad. Improving this situation calls for implementation of the sensors in processes with a smaller feature size which naturally imp...

  7. A radiation-hardened two transistor memory cell for monolithic active pixel sensors in STAR experiment

    International Nuclear Information System (INIS)

    Wei, X; Dorokhov, A; Hu, Y; Gao, D

    2011-01-01

    Radiation tolerance of Monolithic Active Pixel Sensors (MAPS) is dramatically decreased when intellectual property (IP) memories are integrated for fast readout application. This paper presents a new solution to improve radiation hardness and avoid latch-up for memory cell design. The tradeoffs among radiation tolerance, area and speed are significantly considered and analyzed. The cell designed in 0.35 μm process satisfies the radiation tolerance requirements of STAR experiment. The cell size is 4.55 x 5.45 μm 2 . This cell is smaller than the IP memory cell based on the same process and is only 26% of a radiation tolerant 6T SRAM cell used in previous contribution. The write access time of the cell is less than 2 ns, while the read access time is 80 ns.

  8. SCHEME ANALYSIS TREE DIMENSIONS AND TOLERANCES PROCESSING

    OpenAIRE

    Constanta RADULESCU; Liviu Marius CÎRŢÎNĂ; Constantin MILITARU

    2011-01-01

    This paper presents one of the steps that help us to determine the optimal tolerances depending on thetechnological capability of processing equipment. To determine the tolerances in this way is necessary to takethe study and to represent schematically the operations are used in technological process of making a piece.Also in this phase will make the tree diagram of the dimensions and machining tolerances, dimensions andtolerances shown that the design execution. Determination processes, and ...

  9. Generalized tolerance sensitivity and DEA metric sensitivity

    OpenAIRE

    Neralić, Luka; E. Wendell, Richard

    2015-01-01

    This paper considers the relationship between Tolerance sensitivity analysis in optimization and metric sensitivity analysis in Data Envelopment Analysis (DEA). Herein, we extend the results on the generalized Tolerance framework proposed by Wendell and Chen and show how this framework includes DEA metric sensitivity as a special case. Further, we note how recent results in Tolerance sensitivity suggest some possible extensions of the results in DEA metric sensitivity.

  10. Generalized tolerance sensitivity and DEA metric sensitivity

    Directory of Open Access Journals (Sweden)

    Luka Neralić

    2015-03-01

    Full Text Available This paper considers the relationship between Tolerance sensitivity analysis in optimization and metric sensitivity analysis in Data Envelopment Analysis (DEA. Herein, we extend the results on the generalized Tolerance framework proposed by Wendell and Chen and show how this framework includes DEA metric sensitivity as a special case. Further, we note how recent results in Tolerance sensitivity suggest some possible extensions of the results in DEA metric sensitivity.

  11. Biosentinel: Improving Desiccation Tolerance of Yeast Biosensors for Deep-Space Missions

    Science.gov (United States)

    Dalal, Sawan; Santa Maria, Sergio R.; Liddell, Lauren; Bhattacharya, Sharmila

    2017-01-01

    BioSentinel is one of 13 secondary payloads to be deployed on Exploration Mission 1 (EM-1) in 2019. We will use the budding yeast Saccharomyces cerevisiae as a biosensor to determine how deep-space radiation affects living organisms and to potentially quantify radiation levels through radiation damage analysis. Radiation can damage DNA through double strand breaks (DSBs), which can normally be repaired by homologous recombination. Two yeast strains will be air-dried and stored in microfluidic cards within the payload: a wild-type control strain and a radiation sensitive rad51 mutant that is deficient in DSB repairs. Throughout the mission, the microfluidic cards will be rehydrated with growth medium and an indicator dye. Growth rates of each strain will be measured through LED detection of the reduction of the indicator dye, which correlates with DNA repair and the amount of radiation damage accumulated. Results from BioSentinel will be compared to analog experiments on the ISS and on Earth. It is well known that desiccation can damage yeast cells and decrease viability over time. We performed a screen for desiccation-tolerant rad51 strains. We selected 20 re-isolates of rad51 and ran a weekly screen for desiccation-tolerant mutants for five weeks. Our data shows that viability decreases over time, confirming previous research findings. Isolates L2, L5 and L14 indicate desiccation tolerance and are candidates for whole-genome sequencing. More time is needed to determine whether a specific strain is truly desiccation tolerant. Furthermore, we conducted an intracellular trehalose assay to test how intracellular trehalose concentrations affect or protect the mutant strains against desiccation stress. S. cerevisiae cell and reagent concentrations from a previously established intracellular trehalose protocol did not yield significant absorbance measurements, so we tested varying cell and reagent concentrations and determined proper concentrations for successful

  12. Identification of Novel Desiccation-Tolerant S. cerevisiae Strains for Deep Space Biosensors

    Science.gov (United States)

    Tieze, Sofia Massaro; Santa Maria, Sergio R.; Liddell, Lauren; Bhattacharya, Sharmila

    2017-01-01

    NASA's BioSentinel mission, a secondary payload that will fly on the Space Launch Systems first Exploration Mission (EM-1), utilizes the budding yeast S. cerevisiae to study the biological response to the deep space radiation environment. Yeast samples are desiccated prior to launch to suspend growth and metabolism while the spacecraft travels to its target heliocentric orbit beyond Low Earth Orbit. Each sample is then rehydrated at the desired time points to reactivate the cells. A major risk in this mission is the loss of cell viability that occurs in the recovery period following the desiccation and rehydration process. Cell survival is essential for the detection of the biological response to features in the deep space environment, including ionizing radiation.The aim of this study is to mitigate viable cell loss in future biosensors by identifying mutations and genes that confer tolerance to desiccation stress in rad51, a radiation-sensitive yeast strain. We initiated a screen for desiccation-tolerance after rehydrating cells that were desiccated for three years, and selected various clones exhibiting robust growth. To verify retention of radiation sensitivity in the isolated clonesa crucial feature for a successful biosensorwe exposed them to ionizing radiation. Finally, to elucidate the genetic and molecular bases for observed desiccation-tolerance, we will perform whole-genome sequencing of those rad51 clones that exhibit both robust growth and radiation sensitivity following desiccation. The identification and characterization of desiccation-tolerant strains will allow us to engineer a biological model that will be resilient in face of the challenges of the deep space environment, and will thus ensure the experimental success of future biosensor missions.

  13. Re-irradiation tolerance in the rat spinal cord

    International Nuclear Information System (INIS)

    Shun Wong, C.; Poon, J.K.; Hill, R.P.

    1993-01-01

    The influence of the level of initial radiation damage on the long term recovery and re-irradiation tolerance in the rat spinal cord was investigated. Rats were irradiated with 0, 10, 20, 30 and 36 daily fractions of 2.15 Gy initially representing 0, 25, 50, 75 and 90% of cord tolerance. After an interval of 20 weeks, retreatments were given using graded single doses of X-ray. The end-point was paralysis of the forelimbs due to white matter necrosis. Latent times to paralysis were inversely proportional to the level of initial injury and retreatment doses. The retreatment ED 50 s were 19.0, 17.0, 15.7, 14.0 and 11.8 Gy for the control animals and animals irradiated initially with 10. 20, 30 and 36 fractions of 2.15 Gy respectively. Using the extrapolated response dose (ERD) concept, α/β of 3.0 Gy, the retreatment of ED 50 s in % ERD were 81, 70, 58 and 42% after initial doses of 25, 50, 75 and 90% ERD respectively. The level of initial injury appeared to influence the proportion of residual injury. For an initial injury of 25 and 90% of ERD, the respective residual injury was 74 and 65% of the initial damage; for an initial injury of 50 and 75% ERD, the residual injury decreased to 59 and 57% respectively. It is concluded that there was significant long-term recovery in the rat spinal cord, and that the level of initial radiation damage influenced both the treatment tolerance and the time expression of injury. (author). tabs

  14. Radiation protection

    International Nuclear Information System (INIS)

    Jain, Aman; Sharma, Shivam; Parasher, Abhishek

    2014-01-01

    Radiation dose measurement, field of radiobiology, is considered to be critical factor for optimizing radiation protection to the health care practitioners, patients and the public. This lead to equipment that has dose - area product meters permanently installed. In many countries and even institution, the range of equipment is vast and with the opportunity for radiation protection and dose recording varies considerably. Practitioners must move with the changed demands of radiation protection but in many cases without assistance of modern advancements in technology Keeping the three basic safety measures Time, Dose and Shielding we can say 'Optimum dose is safe dose' instead of 'No dose is safe dose'. The purpose enclosed within the title 'Radiation Protection'. The use of radiation is expanding widely everyday around the world and crossing boundaries of medical imaging, diagnostic and. The way to get the ''As low as reasonably achievable' is only achievable by using methodology of radiation protection and to bring the concern of general public and practitioners over the hazards of un-necessary radiation dose. Three basic principles of radiation protection are time, distance and shielding. By minimizing the exposure time increasing the distance and including the shielding we can reduce the optimum range of dose. The ability of shielding material to attenuate radiation is generally given as half value layer. This is the thickness of the material which will reduce the amount of radiation by 50%. Lab coat and gloves must be worn when handling radioactive material or when working in a labeled radiation work area. Safety glasses or other appropriate splash shields should be used when handling radioactive material. 1. Reached to low dose level to occupational workers, public as per prescribed dose limit. 2. By mean of ALARA principle we achieved the protection from radiation besides us using the radiation for our benefit

  15. An analysis of tolerance levels in IMRT quality assurance procedures

    International Nuclear Information System (INIS)

    Basran, Parminder S.; Woo, Milton K.

    2008-01-01

    Increased use of intensity modulated radiation therapy (IMRT) has resulted in increased efforts in patient quality assurance (QA). Software and detector systems intended to streamline the IMRT quality assurance process often report metrics, such as percent discrepancies between measured and computed doses, which can be compared to benchmark or threshold values. The purpose of this work is to examine the relationships between two different types of IMRT QA processes in order to define, or refine, appropriate tolerances values. For 115 IMRT plans delivered in a 3 month period, we examine the discrepancies between (a) the treatment planning system (TPS) and results from a commercial independent monitor unit (MU) calculation program; (b) TPS and results from a commercial diode-array measurement system; and (c) the independent MU calculation and the diode-array measurements. Statistical tests were performed to assess significance in the IMRT QA results for different disease site and machine models. There is no evidence that the average total dose discrepancy in the monitor unit calculation depends on the disease site. Second, the discrepancies in the two IMRT QA methods are independent: there is no evidence that a better --or worse--monitor unit validation result is related to a better--or worse--diode-array measurement result. Third, there is marginal benefit in repeating the independent MU calculation with a more suitable dose point, if the initial IMRT QA failed a certain tolerance. Based on these findings, the authors conclude at some acceptable tolerances based on disease site and IMRT QA method. Specifically, monitor unit validations are expected to have a total dose discrepancy of 3% overall, and 5% per beam, independent of disease site. Diode array measurements are expected to have a total absolute dose discrepancy of 3% overall, and 3% per beam, independent of disease site. The percent of pixels exceeding a 3% and 3 mm threshold in a gamma analysis should be

  16. 76 FR 22045 - Fluopicolide; Pesticide Tolerances

    Science.gov (United States)

    2011-04-20

    ... regulation establishes tolerances for residues of fluopicolide and its metabolites in or on multiple... occurred at dose levels where significant maternal toxicity (severe body weight gain decrements and...

  17. Enhancing drought tolerance in C(4) crops.

    Science.gov (United States)

    Lopes, Marta S; Araus, Jose Luis; van Heerden, Philippus D R; Foyer, Christine H

    2011-05-01

    Adaptation to abiotic stresses is a quantitative trait controlled by many different genes. Enhancing the tolerance of crop plants to abiotic stresses such as drought has therefore proved to be somewhat elusive in terms of plant breeding. While many C(4) species have significant agronomic importance, most of the research effort on improving drought tolerance has focused on maize. Ideally, drought tolerance has to be achieved without penalties in yield potential. Possibilities for success in this regard are highlighted by studies on maize hybrids performed over the last 70 years that have demonstrated that yield potential and enhanced stress tolerance are associated traits. However, while our understanding of the molecular mechanisms that enable plants to tolerate drought has increased considerably in recent years, there have been relatively few applications of DNA marker technologies in practical C(4) breeding programmes for improved stress tolerance. Moreover, until recently, targeted approaches to drought tolerance have concentrated largely on shoot parameters, particularly those associated with photosynthesis and stay green phenotypes, rather than on root traits such as soil moisture capture for transpiration, root architecture, and improvement of effective use of water. These root traits are now increasingly considered as important targets for yield improvement in C(4) plants under drought stress. Similarly, the molecular mechanisms underpinning heterosis have considerable potential for exploitation in enhancing drought stress tolerance. While current evidence points to the crucial importance of root traits in drought tolerance in C(4) plants, shoot traits may also be important in maintaining high yields during drought.

  18. Synthesis of Fault-Tolerant Embedded Systems

    DEFF Research Database (Denmark)

    Eles, Petru; Izosimov, Viacheslav; Pop, Paul

    2008-01-01

    This work addresses the issue of design optimization for fault- tolerant hard real-time systems. In particular, our focus is on the handling of transient faults using both checkpointing with rollback recovery and active replication. Fault tolerant schedules are generated based on a conditional...... process graph representation. The formulated system synthesis approaches decide the assignment of fault-tolerance policies to processes, the optimal placement of checkpoints and the mapping of processes to processors, such that multiple transient faults are tolerated, transparency requirements...

  19. Establishing soil loss tolerance: an overview

    Directory of Open Access Journals (Sweden)

    Costanza Di Stefano

    2016-09-01

    Full Text Available Soil loss tolerance is a criterion for establishing if a soil is potentially subjected to erosion risk, productivity loss and if a river presents downstream over-sedimentation or other off-site effects are present at basin scale. At first this paper reviews the concept of tolerable soil loss and summarises the available definitions and the knowledge on the recommended values and evaluating criteria. Then a threshold soil loss value, at the annual temporal scale, established for limiting riling was used for defining the classical soil loss tolerance. Finally, some research needs on tolerable soil loss are listed.

  20. Cumulative radiation effect

    International Nuclear Information System (INIS)

    Kirk, J.; Gray, W.M.; Watson, E.R.

    1977-01-01

    In five previous papers, the concept of Cumulative Radiation Effect (CRE) has been presented as a scale of accumulative sub-tolerance radiation damage, with a unique value of the CRE describing a specific level of radiation effect. Simple nomographic and tabular methods for the solution of practical problems in radiotherapy are now described. An essential feature of solving a CRE problem is firstly to present it in a concise and readily appreciated form, and, to do this, nomenclature has been introduced to describe schedules and regimes as compactly as possible. Simple algebraic equations have been derived to describe the CRE achieved by multi-schedule regimes. In these equations, the equivalence conditions existing at the junctions between schedules are not explicit and the equations are based on the CREs of the constituent schedules assessed individually without reference to their context in the regime as a whole. This independent evaluation of CREs for each schedule has resulted in a considerable simplification in the calculation of complex problems. The calculations are further simplified by the use of suitable tables and nomograms, so that the mathematics involved is reduced to simple arithmetical operations which require at the most the use of a slide rule but can be done by hand. The order of procedure in the presentation and calculation of CRE problems can be summarised in an evaluation procedure sheet. The resulting simple methods for solving practical problems of any complexity on the CRE-system are demonstrated by a number of examples. (author)

  1. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  2. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

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

  3. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

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

  4. Radiation-hardened CMOS integrated circuits

    International Nuclear Information System (INIS)

    Derbenwick, G.F.; Hughes, R.C.

    1977-01-01

    Electronic circuits that operate properly after exposure to ionizing radiation are necessary for nuclear weapon systems, satellites, and apparatus designed for use in radiation environments. The program to develop and theoretically model radiation-tolerant integrated circuit components has resulted in devices that show an improvement in hardness up to a factor of ten thousand over earlier devices. An inverter circuit produced functions properly after an exposure of 10 6 Gy (Si) which, as far as is known, is the record for an integrated circuit

  5. Bracketing effects on risk tolerance

    Directory of Open Access Journals (Sweden)

    Ester Moher

    2010-08-01

    Full Text Available Research has shown that risk tolerance increases when multiple decisions and associated outcomes are presented together in a broader ``bracket'' rather than one at a time. The present studies disentangle the influence of problem bracketing (presenting multiple investment options together from that of outcome bracketing (presenting the aggregated outcomes of multiple decisions, factors which have been deliberately confounded in previous research. In the standard version of the bracketing task, in which participants decide how much of an initial endowment to invest into each in a series of repeated, identical gambles, we find a problem bracketing effect but not an outcome bracketing effect. However, this pattern of results does not generalize to the cases of non-identical gambles nor discrete choice, where we fail to find the standard bracketing effect.

  6. Euro-Multiculturalism and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    The underlying concept of multiculturalism in many European discussions is different from that made prominent by the classic cases, e.g. in Canada, that have functioned as paradigm cases which the most prominent theories of multiculturalism have been tailored to fit and justify. “Euro-multicultur......The underlying concept of multiculturalism in many European discussions is different from that made prominent by the classic cases, e.g. in Canada, that have functioned as paradigm cases which the most prominent theories of multiculturalism have been tailored to fit and justify. “Euro......, and b) that it is under-inclusive in the sense that it collapses multiculturalism into standard liberal political theory and fails to explain what is distinctive about multiculturalism. Finally the paper shows that multiculturalism in this sense can involve issues of toleration....

  7. Targeting phenotypically tolerant Mycobacterium tuberculosis

    Science.gov (United States)

    Gold, Ben; Nathan, Carl

    2016-01-01

    While the immune system is credited with averting tuberculosis in billions of individuals exposed to Mycobacterium tuberculosis, the immune system is also culpable for tempering the ability of antibiotics to deliver swift and durable cure of disease. In individuals afflicted with tuberculosis, host immunity produces diverse microenvironmental niches that support suboptimal growth, or complete growth arrest, of M. tuberculosis. The physiological state of nonreplication in bacteria is associated with phenotypic drug tolerance. Many of these host microenvironments, when modeled in vitro by carbon starvation, complete nutrient starvation, stationary phase, acidic pH, reactive nitrogen intermediates, hypoxia, biofilms, and withholding streptomycin from the streptomycin-addicted strain SS18b, render M. tuberculosis profoundly tolerant to many of the antibiotics that are given to tuberculosis patients in a clinical setting. Targeting nonreplicating persisters is anticipated to reduce the duration of antibiotic treatment and rate of post-treatment relapse. Some promising drugs to treat tuberculosis, such as rifampicin and bedaquiline, only kill nonreplicating M. tuberculosis in vitro at concentrations far greater than their minimal inhibitory concentrations against replicating bacilli. There is an urgent demand to identify which of the currently used antibiotics, and which of the molecules in academic and corporate screening collections, have potent bactericidal action on nonreplicating M. tuberculosis. With this goal, we review methods of high throughput screening to target nonreplicating M. tuberculosis and methods to progress candidate molecules. A classification based on structures and putative targets of molecules that have been reported to kill nonreplicating M. tuberculosis revealed a rich diversity in pharmacophores. However, few of these compounds were tested under conditions that would exclude the impact of adsorbed compound acting during the recovery phase of

  8. Tracking the evolution of a cold stress associated gene family in cold tolerant grasses

    DEFF Research Database (Denmark)

    Sandve, Simen R; Rudi, Heidi; Asp, Torben

    2008-01-01

    to the repeat motifs of the IRI-domain in cold tolerant grasses. Finally we show that the LRR-domain of carrot and grass IRI proteins both share homology to an Arabidopsis thaliana LRR-trans membrane protein kinase (LRR-TPK). Conclusion The diverse IRI-like genes identified in this study tell a tale...... of a complex evolutionary history including birth of an ice binding domain, a burst of gene duplication events after cold tolerant grasses radiated from rice, protein domain structure differentiation between paralogs, and sub- and/or neofunctionalisation of IRI-like proteins. From our sequence analysis we...

  9. 77 FR 4890 - Damage Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures, and Damage Tolerance...

    Science.gov (United States)

    2012-02-01

    ...-AJ52, 2120-AJ51 Damage Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures, and Damage Tolerance and Fatigue Evaluation for Metallic Structures; Correction AGENCY: Federal Aviation Administration... Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures'' (76 FR 74655), published December 1...

  10. Dose effect relationships in cervical and thoracic radiation myelopathies

    International Nuclear Information System (INIS)

    Holdorff, B.

    1980-01-01

    The course and prognosis of radiation myelopathies are determined by 3 factors: the segmental (vertical) location of the lesion, the extent of the transverse syndrome (complete or incomplete) and the radiation dose. The median spinal dose in cervical radiation myelopathies with fatal outcome was higher than in survivals with an incomplete transverse syndrome. In thoracic radiation myelopathies a dose difference between complete and incomplete transverse syndromes could be found as well. Incomplete transverse syndromes as submaximum radiation injuries are more suitable for the determination of the spinal tolerance dose than complete transverse syndromes. The lowest threshold could be stated for cases following high-volume irradiation of the lymphatic system. (Auth.)

  11. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation

    International Nuclear Information System (INIS)

    Gaikwad, Pallavi S.; Panicker, Lata; Mohole, Madhura; Sawant, Sangeeta; Mukhopadhyaya, Rita; Nath, Bimalendu B.

    2016-01-01

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.

  12. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gaikwad, Pallavi S. [Stress Biology Research Laboratory, Department of Zoology, Savitribai Phule University, Pune, 411007 (India); Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Panicker, Lata [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Mohole, Madhura; Sawant, Sangeeta [Bioinformatics Center, Savitribai Phule Pune University, Pune, 411007 (India); Mukhopadhyaya, Rita [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Nath, Bimalendu B., E-mail: bbnath@gmail.com [Stress Biology Research Laboratory, Department of Zoology, Savitribai Phule University, Pune, 411007 (India)

    2016-08-05

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.

  13. Radiation injury

    International Nuclear Information System (INIS)

    Hubner, K.F.

    1988-01-01

    Radiation accidents and incidents continue to be of great interest and concern to the public. Issues such as the threat of nuclear war, the Chernobyl reactor accident, or reports of sporadic incidences of accidental radiation exposure keep this interest up and maintain a high level of fear among the public. In this climate of real concern and radiation phobia, physicians should not only be prepared to answer questions about acute or late effects of ionizing radiation, but also be able to participate in the initial assessment and management of individuals who have been exposed to ionizing radiation or contaminated with radioactive material. Some of the key facts about radiation injury and its medical treatment are discussed by the author

  14. Cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Capdevielle, J N

    1984-01-01

    First, the different instruments and techniques of cosmic particle detection are presented. Then the passage of the cosmic particles through the atmosphere is studied: electrons, photons, muons. The collective behavior of the different categories is also studied, the electromagnetic cascade is distinguished from the hadron cascade. Through the principal physical properties of the radiation and the medium, the ''mean'' aspects of the radiation are then successively dealt with out of the atmosphere, at different altitudes until the sea level, then at great depths. A chapter is devoted to cosmic radiation of more than 10,000 GeV, studied separately. Then solar radiation in universe is studied through their propagation in solar system and their origin. At last, the cosmic radiation effects are studied in environment (cosmic biophysics) and some applications of cosmic radiation are presented.

  15. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk

  16. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  17. Radiation meter

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, P H

    1990-05-30

    Measuring means comprising first and second silicon PIN diode detectors both being covered with a thin layer of conducting material and the second detector being additionally covered with a relatively thick layer of material, the thickness being chosen such that beta radiation dose rate can be measured in beta radiation fields of high or medium energy, and in the presence of X and gamma radiation. (author). 2 figs.

  18. Radiation regulation

    International Nuclear Information System (INIS)

    Braithwaite, J.; Grabosky, P.

    1985-01-01

    The five main areas of radiation regulation considered are radiation exposure in the mining of uranium and other minerals, exposure in the use of uranium in nuclear reactors, risks in the transport of radioactive materials and hazards associated with the disposal of used materials. In Australia these problems are regulated by mines departments, the Australian Atomic Energy Commission and radiation control branches in state health departments. Each of these instutional areas of regulation is examined

  19. Radiation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on radiation chemistry of heavy elements that includes the following topics: radiation chemistry of plutonium in nitric acid solutions (spectrophotometric analysis and gamma radiolysis of Pu(IV) and Pu(VI) in nitric acid solution); EPR studies of intermediates formed in radiolytic reactions with aqueous medium; two-phase radiolysis and its effect on the distribution coefficient of plutonium; and radiation chemistry of nitric acid. (DHM)

  20. Tolerance of the Brachial Plexus to High-Dose Reirradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Allen M., E-mail: achen5@kumc.edu; Yoshizaki, Taeko; Velez, Maria A.; Mikaeilian, Argin G.; Hsu, Sophia; Cao, Minsong

    2017-05-01

    Purpose: To study the tolerance of the brachial plexus to high doses of radiation exceeding historically accepted limits by analyzing human subjects treated with reirradiation for recurrent tumors of the head and neck. Methods and Materials: Data from 43 patients who were confirmed to have received overlapping dose to the brachial plexus after review of radiation treatment plans from the initial and reirradiation courses were used to model the tolerance of this normal tissue structure. A standardized instrument for symptoms of neuropathy believed to be related to brachial plexus injury was utilized to screen for toxicity. Cumulative dose was calculated by fusing the initial dose distributions onto the reirradiation plan, thereby creating a composite plan via deformable image registration. The median elapsed time from the initial course of radiation therapy to reirradiation was 24 months (range, 3-144 months). Results: The dominant complaints among patients with symptoms were ipsilateral pain (54%), numbness/tingling (31%), and motor weakness and/or difficulty with manual dexterity (15%). The cumulative maximum dose (Dmax) received by the brachial plexus ranged from 60.5 Gy to 150.1 Gy (median, 95.0 Gy). The cumulative mean (Dmean) dose ranged from 20.2 Gy to 111.5 Gy (median, 63.8 Gy). The 1-year freedom from brachial plexus–related neuropathy was 67% and 86% for subjects with a cumulative Dmax greater than and less than 95.0 Gy, respectively (P=.05). The 1-year complication-free rate was 66% and 87%, for those reirradiated within and after 2 years from the initial course, respectively (P=.06). Conclusion: The development of brachial plexus–related symptoms was less than expected owing to repair kinetics and to the relatively short survival of the subject population. Time-dose factors were demonstrated to be predictive of complications.