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Sample records for forschungsreaktor triga heidelberg

  1. Completed Decommissioning of the Research Reactor TRIGA Heidelberg We are specialised in Decommissioning a Research Reactor in Germany now

    SciTech Connect

    Juenger-Graef, B.; Hoever, K.; Moser, T.; Berthold, M.; Blenski, H.J.

    2006-07-01

    This paper describes the decommissioning of the TRIGA Heidelberg II reactor which was used until 1999, and of the TRIGA Heidelberg I reactor, which was for the last 20 years in a safe containment. (authors)

  2. Reeducation at Heidelberg University.

    ERIC Educational Resources Information Center

    Giles, Geoffrey J.

    1997-01-01

    Utilizes German archival records to illuminate crucial post-war events at Heidelberg University. The university became the focal point of attempts to define the theoretical and practical meaning of "geistige Umerziehung" (spiritual reeducation). Discusses the conflict between U.S. authorities and such esteemed German scholars as Karl Jaspers and…

  3. Survival of Salmonella Heidelberg in hummus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella Heidelberg is the fourth-most commonly reported Salmonella serotype to cause human illness. There have been several outbreaks and recalls caused by S. Heidelberg in ready to eat foods. Recently, 700 people became ill from ingesting hummus shirazi contaminated with S. Heidelberg. This stud...

  4. Progress at the Heidelberg EBIT

    NASA Astrophysics Data System (ADS)

    Crespo López-Urrutia, J. R.; Braun, J.; Brenner, G.; Bruhns, H.; Dimopoulou, C.; Draganic, I. N.; Fischer, D.; González Martínez, A. J.; Lapierre, A.; Mironov, V.; Moshammer, R.; Soria Orts, R.; Tawara, H.; Trinczek, M.; Ullrich, J.

    2004-01-01

    Two years after the relocation of the Heidelberg EBIT, several experiments are already in operation. Spectroscopic measurements in the optical region have delivered the most precise reported wavelengths for highly charged ions, in the case of the forbidden transitions of Ar XIV and Ar XV. The lifetimes of the metastable levels involved in those transitions has been determined with an error of less than 0.2%. A new, fully automatized x-ray crystal spectrometer allows systematic measurements with very high precision and reproducibility. Absolute measurements of the Lyman series of H-like ions are currently underway. Dielectronic recombination studies have yielded information on rare processes, as two-electron-one photon transitions in Ar16+, or the interference effects between dielectronic and radiative recombination in Hg77+. The apparatus can now operate at electron beam currents of more than 500 mA, and energies up to 100 keV. A further beam energy increase is planned in the near future. Ions can be extracted from the trap and transported to external experiments. Up to 4 × 107 Ar16+ ions per second can be delivered to a 1 cm diameter target at 10 m distance. Charge-exchange experiments with U64+ colliding with a cold He atomic beam have been carried out, as well as experiments aiming at the optimization of the charge state distribution of the extracted via dielectronic recombination. Two new EBITs, currently in advanced state of construction in Heidelberg, will be used for experiments at the VUV free electron laser at TESLA (Hamburg) and for the charge breeding of short-lived radioactive isotopes at the TRIUMF ISAC facility.

  5. NRF TRIGA packaging

    SciTech Connect

    Clements, M.D.

    1995-11-01

    Training Reactor Isotopes, General Atomics (TRIGA{reg_sign}) Reactors are in use at four US Department of Energy (DOE) complex facilities and at least 23 university, commercial, or government facilities. The development of the Neutron Radiography Facility (NRF) TRIGA packaging system began in October 1993. The Hanford Site NRF is being shut down and requires an operationally user-friendly transportation and storage packaging system for removal of the TRIGA fuel elements. The NRF TRIGA packaging system is designed to remotely remove the fuel from the reactor and transport the fuel to interim storage (up to 50 years) on the Hanford Site. The packaging system consists of a cask and an overpack. The overpack is used only for transport and is not necessary for storage. Based upon the cask`s small size and light weight, small TRIGA reactors will find it versatile for numerous refueling and fuel storage needs. The NRF TRIGA packaging design also provides the basis for developing a certifiable and economical packaging system for other TRIGA reactor facilities. The small size of the NRF TRIGA cask also accommodates placing the cask into a larger certified packaging for offsite transport. The Westinghouse Hanford Company NRF TRIGA packaging, as described herein can serve other DOE sites for their onsite use, and the design can be adapted to serve university reactor facilities, handling a variety of fuel payloads.

  6. Heidelberg's Lessons on Literacy, History, and Understanding.

    ERIC Educational Resources Information Center

    Call, Jolayne Sillito

    2000-01-01

    This personal response to German history by a professor attending a major conference at the University of Heidelberg reflects on the country's long history of education and research, the role of language in history, a speech urging tolerance by the Dutch woman who protected Anne Frank's family, and her reactions to a visit to the Dachau…

  7. Assessing the Significance of Salmonella Heidelberg Infections in Egg-Laying Flocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella Heidelberg has been common in North American poultry (including commercial laying flocks) for many years. Public health authorities have implicated both poultry meat and eggs as significant sources for the transmission of S. Heidelberg infections to humans. S. Heidelberg colonizes the int...

  8. Extension of TRIGA reactor capabilities

    SciTech Connect

    Gietzen, A.J.

    1980-07-01

    The first TRIGA reactor went into operation at 10 kW about 22 years ago. Since that time 55 TRIGAs have been put into operation including steady-state powers up to 14,000 kW and pulsing reactors that pulse to 20,000,000 kW. Five more are under construction and a proposal will soon be submitted for a reactor of 25,000 kW. Along with these increases in power levels (and the corresponding fluxes) the experimental facilities have also been expanded. In addition to the installation of new TRIGA reactors with enhanced capabilities many of the older reactors have been modified and upgraded. Also, a number of reactors originally fueled with plate fuel were converted to TRIGA fuel to take advantage of the improved technical and safety characteristics, including the ability for pulsed operation. In order to accommodate increased power and performance the fuel has undergone considerable evolution. Most of the changes have been in the geometry, enrichment and cladding material. However, more recently further development on the UZrH alloy has been carried out to extend the uranium content up to 45% by weight. This increased U content is necessary to allow the use of less than 20% enrichment in the higher powered reactors while maintaining longer core lifetime. The instrumentation and control system has undergone remarkable improvement as the electronics technology has evolved so rapidly in the last two decades. The information display and the circuitry logic has also undergone improvements for enhanced ease of operation and safety. (author)

  9. TRIGA research reactor activities around the world

    SciTech Connect

    Chesworth, R.H.; Razvi, J.; Whittemore, W.L. )

    1991-11-01

    Recent activities at several overseas TRIGA installations are discussed in this paper, including reactor performance, research programs under way, and plans for future upgrades. The following installations are included: (1) 14,000-kW TRIGA at the Institute for Nuclear Research, Pitesti, Romania; (2) 2,000-kW TRIGA Mark II at the Institute of Nuclear Technology, Dhaka, Bangladesh; (3) 3,000-kW TRIGA conversion, Philippine Nuclear Research Institute, Quezon City, Philippines; and (4) other ongoing installations, including a 1,500-kW TRIGA Mark II at Rabat, Morocco, and a 1,000-kW conversion/upgrade at the Institute Asunto Nucleares, Bogota, Columbia.

  10. Progress with the MPIK/UW-PTMS in Heidelberg

    NASA Astrophysics Data System (ADS)

    Diehl, Christoph; Blaum, Klaus; Höcker, Martin; Ketter, Jochen; Pinegar, David B.; Streubel, Sebastian; Van Dyck, Robert S.

    2011-07-01

    The precise determination of the 3He/3H mass ratio, and hence the tritium β-decay endpoint energy E 0, is of relevance for the measurement of the electron anti-neutrino mass performed by the Karlsruhe Tritium Neutrino experiment (KATRIN). By determining this ratio to an uncertainty of 1 part in 1011, systematic errors of E 0 can be checked in the data analysis of KATRIN. To reach this precision, a Penning Trap Mass Spectrometer was constructed at the University of Washington and has been transferred to the Max Planck Institute for Nuclear Physics in Heidelberg at the end of 2008. Since then it is called MPIK/UW-PTMS. Special design features are the utilization of an external ion source and a double trap configuration. The external Penning ion source efficiently ionizes the helium and tritium gas and can give superior elimination of unwanted ion species compared to the previously utilized in-trap-ionization by electrons from a field-emission point. The design as a double Penning trap allows a faster measurement procedure. This should help to avoid problems resulting from long-term drifts in the experimental conditions. Additionally, the laboratory in Heidelberg was carefully prepared to have very stable environmental conditions. Experimental challenges and the first Heidelberg results with the new spectrometer are presented.

  11. Radioactivity of spent TRIGA fuel

    NASA Astrophysics Data System (ADS)

    Usang, M. D.; Nabil, A. R. A.; Alfred, S. L.; Hamzah, N. S.; Abi, M. J. B.; Rawi, M. Z. M.; Abu, M. P.

    2015-04-01

    Some of the oldest TRIGA fuel in the Malaysian Reaktor TRIGA PUSPATI (RTP) is approaching the limit of its end of life with burn-up of around 20%. Hence it is prudent for us to start planning on the replacement of the fuel in the reactor and other derivative activities associated with it. In this regard, we need to understand all of the risk associated with such operation and one of them is to predict the radioactivity of the fuel, so as to estimate the safety of our working conditions. The radioactivity of several fuels are measured and compared with simulation results to confirm the burnup levels of the selected fuels. The radioactivity measurement are conducted inside the water tank to reduce the risk of exposure and in this case the detector wrapped in plastics are lowered under water. In nuclear power plant, the general practice was to continuously burn the fuel. In research reactor, most operations are based on the immediate needs of the reactor and our RTP for example operate periodically. By integrating the burnup contribution for each core configuration, we simplify the simulation of burn up for each core configuration. Our results for two (2) fuel however indicates that the dose from simulation underestimate the actual dose from our measurements. Several postulates are investigated but the underlying reason remain inconclusive.

  12. Radioactivity of spent TRIGA fuel

    SciTech Connect

    Usang, M. D. Nabil, A. R. A.; Alfred, S. L.; Hamzah, N. S.; Abi, M. J. B.; Rawi, M. Z. M.; Abu, M. P.

    2015-04-29

    Some of the oldest TRIGA fuel in the Malaysian Reaktor TRIGA PUSPATI (RTP) is approaching the limit of its end of life with burn-up of around 20%. Hence it is prudent for us to start planning on the replacement of the fuel in the reactor and other derivative activities associated with it. In this regard, we need to understand all of the risk associated with such operation and one of them is to predict the radioactivity of the fuel, so as to estimate the safety of our working conditions. The radioactivity of several fuels are measured and compared with simulation results to confirm the burnup levels of the selected fuels. The radioactivity measurement are conducted inside the water tank to reduce the risk of exposure and in this case the detector wrapped in plastics are lowered under water. In nuclear power plant, the general practice was to continuously burn the fuel. In research reactor, most operations are based on the immediate needs of the reactor and our RTP for example operate periodically. By integrating the burnup contribution for each core configuration, we simplify the simulation of burn up for each core configuration. Our results for two (2) fuel however indicates that the dose from simulation underestimate the actual dose from our measurements. Several postulates are investigated but the underlying reason remain inconclusive.

  13. Nuclear physics in Heidelberg in the years 1950 to 1980. Personal recollections

    NASA Astrophysics Data System (ADS)

    Weidenmüller, Hans A.

    2015-09-01

    After World War II, nuclear physics was a central research theme in the Faculty of Physics and Astronomy at Heidelberg University. That tendency was amplified by the founding of the Max-Planck-Institut für Kernphysik in Heidelberg in 1958. The author witnessed these developments as a student and, later, as a member of the Heidelberg Faculty and of the Max-Planck-Institut.

  14. [A Rosenfeld seminar in Heidelberg 1981 to 1986. A retrospect].

    PubMed

    Schoenhals, Helen; Wildberger, Helga

    2015-01-01

    Rosenfeld led a clinical study group in Heidelberg from 1981 until his death in 1986. His influence on the German psychoanalytic community spread rapidly and widely. The authors, who had been members of the study group, describe their personal experience of Rosenfeld's supervision and how it impacted their own clinical work. They go on to give their personal view of Rosenfeld's great effect on the psychoanalytic community of that time, a time when psychoanalysts eagerly sought help for their treatment of severely disturbed patients in a traumatized post-war nation. PMID:26595989

  15. [Heidelberger study on psychoanalytic therapy of children and adolescents: methodology].

    PubMed

    Fahrig, H

    1999-11-01

    In the representative studies published so far on the outcome of analytic child psychotherapy (Dührssen 1964; Fonagy and Target 1996) no techniques of treatment were mentioned. The following paper describes in detail the technique of treatment on which the Heidelberg Study "On the Therapeutic Outcome in Child and Adolescent Psychotherapy" is based, as it developed from 1975 to 1993 at the Heidelberg Institute for Child and Adolescent Psychotherapy. Starting from Piaget's findings that the cognitive faculties of a child up to the age of 11 completely differ from those of an adult and taking into consideration the cerebral information processing and "the intellect pervadet sensory" (Schopenhauer) it is demonstrated that children take their intrapsychic and interpersonal conflicts into analytic play therapy or into role play on analogous levels. Protected by a safe distance from being aware of their conflicts they will on the analogous levels understand, work through, partially solve their conflicts and make use of it in reality without conscious recognition. The term "analogous level" is defined and the manifold possibilities of therapeutic intervention on this level are demonstrated. The efficacy of therapeutic treatment on analogous levels is discussed. PMID:10616294

  16. Activation analysis using Cornell TRIGA

    SciTech Connect

    Hossain, Tim Z.

    1994-07-01

    A major use of the Cornell TRIGA is for activation analysis. Over the years many varieties of samples have been analyzed from a number of fields of interest ranging from geology, archaeology and textiles. More recently the analysis has been extended to high technology materials for applications in optical and semiconductor devices. Trace analysis in high purity materials like Si wafers has been the focus in many instances, while in others analysis of major/minor components were the goals. These analysis has been done using the delayed mode. Results from recent measurements in semiconductors and other materials will be presented. In addition the near future capability of using prompt gamma activation analysis using the Cornell cold neutron beam will be discussed. (author)

  17. The Heidelberg CSR: Stored Ion Beams in a Cryogenic Environment

    SciTech Connect

    Wolf, A.; Hahn, R. von; Grieser, M.; Orlov, D. A.; Fadil, H.; Welsch, C. P.; Andrianarijaona, V.; Diehl, A.; Schroeter, C. D.; Crespo Lopez-Urrutia, J. R.; Weber, T.; Mallinger, V.; Schwalm, D.; Ullrich, J.; Rappaport, M.; Urbain, X.; Haberstroh, Ch.; Quack, H.; Zajfman, D.

    2006-03-20

    A cryogenic electrostatic ion storage ring CSR is under development at the Max-Planck Institute for Nuclear Physics in Heidelberg, Germany. Cooling of the ultrahigh vacuum chamber is envisaged to lead to extremely low pressures as demonstrated by cryogenic ion traps. The ring will apply electron cooling with electron beams of a few eV up to 200 eV. Through long storage times of 1000 s as well as through the low wall temperature, internal cooling of infrared-active molecular ions to their rotational ground state will be possible and their collisions with merged collinear beams of electrons and neutral atoms can be detected with high energy resolution. In addition storage of slow highly charged ions is foreseen. Using a fixed in-ring gas target and a reaction microscope, collisions of the stored ions at a speed of the order of the atomic unit can be kinematically reconstructed. The layout and the cryogenic concept are introduced.

  18. Heidelberg edge perimeter employment in glaucoma diagnosis--preliminary report.

    PubMed

    Mulak, Małgorzata; Szumny, Dorota; Sieja-Bujewska, Anna; Kubrak, Magdalena

    2012-01-01

    In recent years, the authors have seen huge progress in the diagnosis of eye diseases. One of the new diagnostic devices is HEP (Heidelberg Edge Perimeter) - for early diagnosis of glaucoma and its progression. It combines visual field test and HRT (Heidelberg Retina Tomograph), which allows authors to obtain the image of the mutual relation between the structure and the function of the sight organ. It could be also used to assess patients with impaired retina, optic nerve and neurological deficits. The SAP function is more suitable for the detection and monitoring of neurological deficits, moderately advanced and advanced glaucoma as well as other diseases associated with extensive or deep visual field deficits, such as ischemic optic neuropathy. FDF stimulus was designed specifically to detect early glaucoma-related changes in the visual field. For about a year, the Ophthalmology Clinic in Wrocław has owned a new, unique HEP perimeter. The authors present examples of patients diagnosed and treated at the Clinic, with respect to whom the perimeter results obtained using Octopus type perimeter and HEP contour perimeter have been compared. This method has its advantages: it is non-invasive, objective, provides the opportunity to repeat and compare results obtained from subsequent tests. The disadvantages are the difficulty in adapting to a new stimulus, which is not a circular light stimulus, but an outline that is hard to notice for some patients. Although according to the manufacturer the testing time should not exceed 4-5 minutes, it takes 14-15 minutes in many patients. The test is not suitable for patients showing lower manual skills and less attention and those who tire out easily. The HEP perimeter is an innovative method for diagnosing the earliest changes in ganglion cells, that is pre-perimetric glaucoma, or when changes in the visual field are undetectable in a standard test. PMID:23356204

  19. "Heidelberg standard examination" and "Heidelberg standard procedures" - Development of faculty-wide standards for physical examination techniques and clinical procedures in undergraduate medical education.

    PubMed

    Nikendei, C; Ganschow, P; Groener, J B; Huwendiek, S; Köchel, A; Köhl-Hackert, N; Pjontek, R; Rodrian, J; Scheibe, F; Stadler, A-K; Steiner, T; Stiepak, J; Tabatabai, J; Utz, A; Kadmon, M

    2016-01-01

    The competent physical examination of patients and the safe and professional implementation of clinical procedures constitute essential components of medical practice in nearly all areas of medicine. The central objective of the projects "Heidelberg standard examination" and "Heidelberg standard procedures", which were initiated by students, was to establish uniform interdisciplinary standards for physical examination and clinical procedures, and to distribute them in coordination with all clinical disciplines at the Heidelberg University Hospital. The presented project report illuminates the background of the initiative and its methodological implementation. Moreover, it describes the multimedia documentation in the form of pocketbooks and a multimedia internet-based platform, as well as the integration into the curriculum. The project presentation aims to provide orientation and action guidelines to facilitate similar processes in other faculties. PMID:27579354

  20. A Computer Code for TRIGA Type Reactors.

    Energy Science and Technology Software Center (ESTSC)

    1992-04-09

    Version 00 TRIGAP was developed for reactor physics calculations of the 250 kW TRIGA reactor. The program can be used for criticality predictions, power peaking predictions, fuel element burn-up calculations and data logging, and in-core fuel management and fuel utilization improvement.

  1. Decommissioning of the Northrop TRIGA reactor

    SciTech Connect

    Cozens, George B.; Woo, Harry; Benveniste, Jack; Candall, Walter E.; Adams-Chalmers, Jeanne

    1986-07-01

    An overview of the administrative and operational aspects of decommissioning and dismantling the Northrop Mark F TRIGA Reactor, including: planning and preparation, personnel requirements, government interfacing, costs, contractor negotiations, fuel shipments, demolition, disposal of low level waste, final survey and disposition of the concrete biological shielding. (author)

  2. Effect of essential oil compound on shedding and colonization of Salmonella enterica serovar Heidelberg in broilers.

    PubMed

    Alali, W Q; Hofacre, C L; Mathis, G F; Faltys, G

    2013-03-01

    The objectives of this study were to determine the effect of an essential oil blend (EO; carvacrol, thymol, eucalyptol, lemon) administered in drinking water on the performance, mortality, water consumption, pH of crop and ceca, and Salmonella enterica serovar Heidelberg fecal shedding and colonization in broiler birds following Salmonella Heidelberg challenge and feed withdrawal. Chicks were randomly assigned to water treatments containing 0.05, 0.025, or 0.0125% EO or untreated controls. Treatments were administered in drinking water on 0 to 7 and 35 to 42 d. One-half of the chicks were challenged with Salmonella Heidelberg and placed in pens with unchallenged chicks on d 1. Performance, mortality, water consumption, and pH were determined during the 42-d study. Prevalence of Salmonella Heidelberg was determined on drag swabs (0, 14, and 42 d) and in the ceca and crops (42 d). The 0.05% EO administered in drinking water significantly (P < 0.05) reduced Salmonella Heidelberg colonization in crops of challenged birds, significantly lowered the feed conversion ratio, and increased weight gain compared with controls. The 0.025% and 0.015% EO in drinking water significantly lowered the feed conversion ratio and increased weight gain compared with controls, but did not significantly reduce Salmonella Heidelberg colonization in the crops. The EO in drinking water did not significantly reduce Salmonella Heidelberg colonization in ceca or fecal shedding in broilers. The EO used in the study may control Salmonella Heidelberg contamination in crops of broilers when administered in drinking water and therefore may reduce the potential for cross-contamination of the carcass when the birds are processed. PMID:23436536

  3. Monte Carlo modelling of TRIGA research reactor

    NASA Astrophysics Data System (ADS)

    El Bakkari, B.; Nacir, B.; El Bardouni, T.; El Younoussi, C.; Merroun, O.; Htet, A.; Boulaich, Y.; Zoubair, M.; Boukhal, H.; Chakir, M.

    2010-10-01

    The Moroccan 2 MW TRIGA MARK II research reactor at Centre des Etudes Nucléaires de la Maâmora (CENM) achieved initial criticality on May 2, 2007. The reactor is designed to effectively implement the various fields of basic nuclear research, manpower training, and production of radioisotopes for their use in agriculture, industry, and medicine. This study deals with the neutronic analysis of the 2-MW TRIGA MARK II research reactor at CENM and validation of the results by comparisons with the experimental, operational, and available final safety analysis report (FSAR) values. The study was prepared in collaboration between the Laboratory of Radiation and Nuclear Systems (ERSN-LMR) from Faculty of Sciences of Tetuan (Morocco) and CENM. The 3-D continuous energy Monte Carlo code MCNP (version 5) was used to develop a versatile and accurate full model of the TRIGA core. The model represents in detailed all components of the core with literally no physical approximation. Continuous energy cross-section data from the more recent nuclear data evaluations (ENDF/B-VI.8, ENDF/B-VII.0, JEFF-3.1, and JENDL-3.3) as well as S( α, β) thermal neutron scattering functions distributed with the MCNP code were used. The cross-section libraries were generated by using the NJOY99 system updated to its more recent patch file "up259". The consistency and accuracy of both the Monte Carlo simulation and neutron transport physics were established by benchmarking the TRIGA experiments. Core excess reactivity, total and integral control rods worth as well as power peaking factors were used in the validation process. Results of calculations are analysed and discussed.

  4. NFR TRIGA package design review report

    SciTech Connect

    Clements, M.D.

    1994-08-26

    The purpose of this document is to compile, present and document the formal design review of the NRF TRIGA packaging. The contents of this document include: the briefing meeting presentations, package description, design calculations, package review drawings, meeting minutes, action item lists, review comment records, final resolutions, and released drawings. This design review required more than two meeting to resolve comments. Therefore, there are three meeting minutes and two action item lists.

  5. 14. U.S. TRIGA users conference. Final program and summary of papers

    SciTech Connect

    1994-07-01

    The following papers were presented at the Conference: Early Development and Use of the TRIGA Reactor; Results of the MCNP Analysis of 20/20 LEU Fuel for the Oregon State University TRIGA Reactor; Upgradeable 2MW TRIGA Reactor Design for the Morocco Nuclear Energy Center McClellan Nuclear Radiation Center TRIGA Reactor: Four Years of Operations.

  6. Fission product release from TRIGA-LEU reactor fuels

    SciTech Connect

    Baldwin, N.L.; Foushee, F.C.; Greenwood, J.S

    1980-07-01

    Due to present international concerns over nuclear proliferation, TRIGA reactor fuels will utilize only low-enriched uranium (LEU) (enrichment <20%). This requires increased total uranium loading per unit volume of fuel in order to maintain the appropriate fissile loading. Tests were conducted to determine the fractional release of gaseous and metallic fission products from typical uranium-zirconium hydride TRIGA fuels containing up to 45 wt-% uranium. These tests, performed in late 1977 and early 1978, were similar to those conducted earlier on TRIGA fuels with 8.5 wt-% U. Fission gas release measurements were made on prototypic specimens from room temperature to 1100 deg. C in the TRIGA King Furnace Facility. The fuel specimens were irradiated in the TRIGA reactor at a low power level. The fractional releases of the gaseous nuclides of krypton and xenon were measured under steady-state operating conditions. Clean helium was used to sweep the fission gases released during irradiation from the furnace into a standard gas collection trap for gamma counting. The results of these tests on TRIGA-LEU fuel agree well with data from the similar, earlier tests on TRIGA fuel. The correlation used to calculate the release of fission products from 8.5 wt-% U TRIGA fuel applies equally well for U contents up to 45 wt-%. (author)

  7. 12. U.S. TRIGA users conference. Papers and abstracts

    SciTech Connect

    1990-07-01

    The Conference presentations were devoted to the following topics: new developments and improvements, including modifications of TRIGA reactors and equipment; experiments with TRIGA reactors (Neutron Radiography); radiochemistry, radioisotope production and beam irradiations (experiment applications, simulation); reactor physics - fuel utilization; reactor operation and maintenance experience; safety aspects, licensing and radiation protection.

  8. Antimicrobial resistance of Salmonella enterica serovar Heidelberg isolated from poultry in Alberta.

    PubMed

    St Amand, Joan A; Otto, Simon J G; Cassis, Rashed; Annett Christianson, Colleen B

    2013-08-01

    Salmonella enterica serovar Heidelberg is one of the top three serovars implicated in human infections in Canada. In 2003, the Canadian Integrated Program for Antimicrobial Resistance Surveillance reported antimicrobial resistance (AMR) in S. Heidelberg in Canada. The study objective was to investigate the AMR of S. Heidelberg isolated from poultry in Alberta. We examined 951 S. Heidelberg poultry isolates obtained during 1996 to 2010 and tested against 18 antibiotics using the Sensititre AVIAN1F system. Temporal resistance patterns were analysed using single-level logistic regression models. Continuous variables were included in the multivariable models. Multivariable models were built and variables and interactions were included in these final models. Data were analysed using Stata 11 Intercooled. Ceftiofur resistance ranged annually from 0 to 10.5% and gentamicin resistance ranged annually from 0 to 33.3%; no isolates were enrofloxacin resistant. Resistance to amoxicillin (annual range 0 to 42.6%) varied significantly by time and interaction with commodity type. Meat turkey S. Heidelberg isolates had higher ceftiofur resistance compared with chickens: layers plus layer breeders (odds ratio = 22.6, P < 0.01) and broiler breeders (odds ratio = 9.1, P < 0.01). Gentamicin resistance decreased significantly over the study period (odds ratio = 0.72 per year, P < 0.01). Tetracycline (TET) resistance changed significantly over time (annual range 0 to 39.6%), interacting with poultry commodity type. Meat turkey isolate TET resistance, higher overall than that of chicken, increased throughout the study. All turkey breeder isolates were resistant to TET. In conclusion, this study provides AMR data for S. Heidelberg isolates from the Alberta poultry industry and demonstrated significant trends in resistance, both temporal and between poultry commodities. PMID:23815674

  9. THE JOINT EUROPEAN-UNITED STATES NDEA INSTITUTE FOR ADVANCED STUDY, MANNHEIM-HEIDELBERG.

    ERIC Educational Resources Information Center

    VAN TESLAAR, A.P.

    THE EUROPEAN COORDINATOR AND RESIDENT CO-DIRECTOR OF THE MANNHEIM-HEIDELBERG BRANCH OF THE SUMMER 1966 LANGUAGE INSTITUTE IN FRANCE AND GERMANY PREPARED THIS EVALUATION OF THE INTERNATIONAL VENTURE. DESIGNED TO ANALYZE THE INNOVATIONAL ASPECTS OF THE 1966 INSTITUTE WITH THE IDEA OF STRENGTHENING THE EFFECTIVENESS OF THIS AND SIMILAR PROGRAMS, THE…

  10. Multidrug-Resistant Salmonella Heidelberg Associated with Mechanically Separated Chicken at a Correctional Facility.

    PubMed

    Taylor, Amanda L; Murphree, Rendi; Ingram, L Amanda; Garman, Katie; Solomon, Deborah; Coffey, Eric; Walker, Deborah; Rogers, Marsha; Marder, Ellyn; Bottomley, Marie; Woron, Amy; Thomas, Linda; Roberts, Sheri; Hardin, Henrietta; Arjmandi, Parvin; Green, Alice; Simmons, Latoya; Cornell, Allyson; Dunn, John

    2015-12-01

    We describe multidrug-resistant (MDR) Salmonella Heidelberg infections associated with mechanically separated chicken (MSC) served at a county correctional facility. Twenty-three inmates met the case definition. All reported diarrhea, 19 (83%) reported fever, 16 (70%) reported vomiting, 4 (17%) had fever ≥103°F, and 3 (13%) were hospitalized. A case-control study found no single food item significantly associated with illness. Salmonella Heidelberg with an indistinguishable pulsed-field gel electrophoresis pattern was isolated from nine stool specimens; two isolates displayed resistance to a total of five drug classes, including the third-generation cephalosporin, ceftriaxone. MDR Salmonella Heidelberg might have contributed to the severity of illness. Salmonella Heidelberg indistinguishable from the outbreak subtype was isolated from unopened MSC. The environmental health assessment identified cross-contamination through poor food-handling practices as a possible contributing factor. Proper hand-washing techniques and safe food-handling practices were reviewed with the kitchen supervisor. PMID:26540115

  11. Novel Surveillance of Salmonella enterica Serotype Heidelberg Epidemics in a Closed Community

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During 2003-2005, a systematic and regularly timed human and farm-animal wastewater sampling scheme existed in several prison units in Texas. In early July 2003, an outbreak of gastroenteritis caused by Salmonella enterica serotype Heidelberg occurred in the human population at one site. Wastewate...

  12. Fission-product release from TRIGA-LEU reactor fuels

    SciTech Connect

    Baldwin, N.L.; Foushee, F.C.; Greenwood, J.S.

    1980-11-01

    The release of fission products, both gaseous and volatile metals, from TRIGA fuel is important for the analysis of possible accident conditions related to reactor operation and the design of future TRIGA fuel systems. Because of present national concerns over nuclear proliferation, it has become clear that future reactor fuels will, of necessity, utilize low-enriched uranium (LEU, enrichment <20%). This will require increasing the total uranium loading per unit volume of the higher-loaded TRIGA fuels for the purpose of maintaining the appropriate fissile loading. Because of these new developments, tests were conducted to determine the fractional release of gaseous and metallic fission products from typical uranium-zirconium hydride TRIGA fuels containing 8.5 to 45 wt % uranium.

  13. Northrop Triga facility decommissioning plan versus actual results

    SciTech Connect

    Gardner, F.W.

    1986-01-01

    This paper compares the Triga facility decontamination and decommissioning plan to the actual results and discusses key areas where operational activities were impacted upon by the final US Nuclear Regulatory Commission (NRC)-approved decontamination and decommissioning plan. Total exposures for fuel transfer were a factor of 4 less than planned. The design of the Triga reactor components allowed the majority of the components to be unconditionally released.

  14. TRIGA Mark II benchmark experiment; Part II: Pulse operation

    SciTech Connect

    Mele, I.; Ravnik, M.; Trkov, A. )

    1994-01-01

    Experimental results of pulse parameters and control rod worth measurements at TRIGA Mark 2 reactor in Ljubljana are presented. The measurements were performed with a completely fresh, uniform, and compact core. Only standard fuel elements with 12 wt% uranium were used. Special efforts were made to get reliable and accurate results at well-defined experimental conditions, and it is proposed to use the results as a benchmark test case for TRIGA reactors.

  15. The Heidelberg Basin Drilling Project - Sedimentology and Stratigraphy of the Quaternary succession

    NASA Astrophysics Data System (ADS)

    Ellwanger, Dietrich; Gabriel, Gerald; Hahne, Jürgen; Hoselmann, Christian; Menzies, John; Simon, Theo; Weidenfeller, Michael; Wielandt-Schuster, Ulrike

    2010-05-01

    Within the context of the Heidelberg Basin Drilling Project (Gabriel et al. 2008), a detailed sediment succession is presented here based upon deep drillings taken at Heidelberg UniNord and Mannheim Käfertal. Sediment structures, and micromorphological and pollen analyses were conducted and used to reconsider some of the climate transitions within the lower Pleistocene. A new and novel scenario is postulated regarding the preservation of Quaternary sediment packages within the Cenozoic Graben environment of the Heidelberg basin. The palynological evidence comprises the periods of warm climate of the Holsteinian (mainly Abies (fir), some Fagus (beech), Pterocarya & Azolla); the Cromerian (Pinus-Picea-QM (pine-spruce-QM)); the Bavelian (Abies, Tsuga (hemlock fir), QM & phases of increased NAP including Pinus); the Waalian (Abies, Tsuga, QM); and the Tiglian (Fagus & early Pleistocene taxa especially Sciadopytis, downward increasing Tertiary taxa). The sediment package was studied both macroscopically and microscopically. Both techniques provide evidence of fluvial, lacustrine and mass movement sedimentary processes. Some include evidence of periglacial processes (silt droplets within fine grained sands indicative of frozen ground conditions). The periglacial structures are often, not always, accompanied by pollen spectra dominated by pine and NAP. E.g. the Tiglian part of the succession shows periglacial sediment structures at its base and top but not in its middle sections. I.e. it appears not as a series of warm and cold phases but rather as a constant warm period with warm-cold-alternations at its bottom and top. All results illustrate sediment preservation in the Heidelberg basin almost throughout the Quaternary. This may be due to tectonic subsidence, but also to compaction by sediment loading of underlying fine sediments (Oligocene to Quaternary) leading to incomplete but virtually continuous sediment preservation (Tanner et al. 2009). References Gabriel, G

  16. The Haus der Astronomie in Heidelberg-A New Center for Education and Outreach

    NASA Astrophysics Data System (ADS)

    Staude, J.

    2011-06-01

    Since October 2009, a unique facility is being erected on the grounds of the Max Planck Institute for Astronomy on top of the Königstuhl Mountain above Heidelberg, in the immediate vicinity of the State Observatory. It will be dedicated to the communication between scientists, to the development of educational material for junior and high school students, to the training of teachers and student teachers in physics, astronomy and natural sciences, and to the information of the media and the general public about new developments and results in astronomical research. The building will be donated by the Klaus Tschira Foundation, while the Max Planck Society, the University and the City of Heidelberg, and the State Departments of Research and of Education will share the running costs of the new institution.

  17. Association between socioeconomic and demographic characteristics and utilization of colonoscopy in the EPIC-Heidelberg cohort.

    PubMed

    Hermann, Silke; Friedrich, Susanne; Haug, Ulrike; Rohrmann, Sabine; Becker, Nikolaus; Kaaks, Rudolf

    2015-03-01

    We aimed to describe the utilization of colonoscopy and its association with sociodemographic characteristics within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort study. We included 15 014 study participants (43% men) of the EPIC-Heidelberg cohort recruited between 1994 and 1998. At baseline recruitment, as well as in the 3-yearly follow-up surveys, study participants completed questionnaires on lifestyle, socioeconomic background variables, health status, and use of medications and medical services, including colonoscopy examinations. The present analyses focused on participants who completed the question on colonoscopy examination in all follow-up rounds. Our results show that by the end of the fourth follow-up round, more than half of all participants of the EPIC-Heidelberg cohort had had a colonoscopy. Colonoscopy was associated with some socioeconomic and demographic characteristics: a positive association with vocational training level as well as overall socioeconomic status level [International Standard Classification of Education (ISCED) classification]. A negative association was found for household size and employment status. Colonoscopy usage increased steeply within the subgroup of participants older than 55 years of age and decreased again within the subgroup of participants older than 75 years of age. Organized colorectal cancer screening should include a written invitation system, to overcome the problem of sociodemographic-related differential awareness of and attendance at colonoscopy examinations. Also, the high proportion of prescreened individuals should be taken into account to avoid unnecessary re-examinations. PMID:25244156

  18. Subsurface structure and hydrocarbon occurrence, Heidelberg-Sand Hill graben system, southeast Mississippi

    SciTech Connect

    Bowman, J.K.; Meylan, M.A.

    1986-09-01

    The subsurface structure and hydrocarbon distribution of the Heidelberg-Sand Hill graben system have been determined using 575 electric logs, existing field studies, and proprietary seismic data. This graben system, located on the eastern side of the Mississippi Salt basin, extends for about 55 mi north-northwest-south-southeast from Jasper County to Greene County, Mississippi. Heidelberg, Sandersville, Choctaw, Pool Creek, North Wausau, Wausau, Thompson Creek, South Thompson Creek, Flat Branch, North Sand Hill, and Avera oil fields are situated along the graben (from north to south). Cumulative oil production is about 170 million bbl, with about 83% from Heidelberg field. Eutaw and Tuscaloosa sandstones are the chief reservoirs. Structure contour maps and structure cross sections perpendicular to the trend of the graben have been used to define the character of the system. The graben is superimposed on a Louann Salt ridge and associated piercement domes. The location of the salt ridge may be controlled by faulting of the pre-Louann basement (Phillips fault system). Most hydrocarbons are found in upthrown fault closure along either the eastern or western bounding faults. Downthrown Selma chalk, Mooringsport shales, or other impermeable units provide the seal. Minor amounts of oil occur within the graben, either in fault closure or faulted anticlinal closure formed by salt uplift or simultaneous rollover into the principal bounding faults.

  19. 7. biennial U.S. TRIGA users' conference. Papers and abstracts

    SciTech Connect

    1980-07-01

    The conference covers the following topics: new developments in the TRIGA system; uses of microprocessors in control and monitoring and measurement of TRIGA performance parameters; safeguards, emergency planning, reactor standards; research facilities, fuel tests and calculations; TRIGA reactor parameters: emergency training.

  20. A consistent magnetic polarity stratigraphy of Plio-Pleistocene fluvial sediments from the Heidelberg Basin (Germany)

    NASA Astrophysics Data System (ADS)

    Scheidt, Stephanie; Hambach, Ulrich; Rolf, Christian

    2014-05-01

    Deep drillings in the Heidelberg Basins provide access to one of the thickest and most complete successions of Quaternary and Upper Pliocene continental sediments in Central-Europe [1]. In absence of any comprehensive chronostratigraphic model, these sediments are so far classified by lithological and hydrogeological criteria. Therefore the age of this sequence is still controversially discussed ([1], [2]). In spite of the fact that fluvial sediments are a fundamental challenge for the application of magnetic polarity stratigraphy we performed a thorough study on four drilling cores (from Heidelberg, Ludwigshafen and nearby Viernheim). Here, we present the results from the analyses of these cores, which yield to a consistent chronostratigraphic framework. The components of natural remanent magnetisation (NRM) were separated by alternating field and thermal demagnetisation techniques and the characteristic remanent magnetisations (ChRM) were isolated by principle component analysis [3]. Due to the coring technique solely inclination data of the ChRM is used for the determination of the magnetic polarity stratigraphy. Rock magnetic proxies were applied to identify the carriers of the remanent magnetisation. The investigations prove the NRM as a stable, largely primary magnetisation acquired shortly after deposition (PDRM). The Matuyama-Gauss boundary is clearly defined by a polarity change in each core, as suggested in previous work [4]. These findings are in good agreement with the biostratigraphic definition of the base of the Quaternary ([5], [6], [7]). The Brunhes-Matuyama boundary could be identified in core Heidelberg UniNord 1 and 2 only. Consequently, the position of the Jaramillo and Olduvai subchron can be inferred from the lithostratigraphy and the development of fluvial facies architecture in the Rhine system. The continuation of the magnetic polarity stratigraphy into the Gilbert chron (Upper Pliocene) allows alternative correlation schemes for the cores

  1. A 5 MW TRIGA reactor design for radioisotope production

    SciTech Connect

    Veca, Anthony R.; Whittemore, William L.

    1994-07-01

    The production and preparation of commercial-scale quantities of radioisotopes has become an important activity as their medical and industrial applications continue to expand. There are currently various large multipurpose research reactors capable of producing ample quantities of radioisotopes. These facilities, however, have many competing demands placed upon them by a wide variety of researchers and scientific programs which severely limit their radioisotope production capability. A demonstrated need has developed for a simpler reactor facility dedicated to the production of radioisotopes on a commercial basis. This smaller, dedicated reactor could provide continuous fission and activation product radioisotopes to meet commercial requirements for the foreseeable future. The design of a 5 MW TRIGA reactor facility, upgradeable to 10 MW, dedicated to the production of industrial and medical radioisotopes is discussed. A TRIGA reactor designed specifically for this purpose with its demonstrated long core life and simplicity of operation would translate into increased radioisotope production. As an example, a single TRIGA could supply the entire US needs for Mo-99. The facility is based on the experience gained by General Atomics in the design, installation, and construction of over 60 other TRIGAs over the past 35 years. The unique uranium-zirconium hydride fuel makes TRIGA reactors inexpensive to build and operate, reliable in their simplicity, highly flexible due to unique passive safety, and environmentally friendly because of minimal power requirements and long-lived fuel. (author)

  2. Status of the TRIGA shipments to the INEEL from Europe

    SciTech Connect

    Mustin, T.; Stump, R.C.; Tyacke, M.J.

    1997-10-09

    This paper reports the activities underway by the US Department of Energy (DOE) for returning Training, Research, Isotope, General Atomics (TRIGA) spent nuclear fuel (SNF) from foreign research reactors (FRR) in four European countries to the Idaho National Engineering and Environmental Laboratory (INEEL). Those countries are Germany, Italy, Romania, and Slovenia. This is part of the ``Nuclear Weapons Nonproliferation Policy`` of returning research reactor SNF containing uranium enriched in the US. This paper describes the results of a pre-assessment trip in September, 1997, to these countries, including: history of the reactors and research being performed; inventory of TRIGA SNF; fuel types (stainless steel, aluminum, or Incoloy) and enrichments; and each country`s plans for returning their TRIGA SNF to the INEEL.

  3. TRIGA MARK-II source term

    NASA Astrophysics Data System (ADS)

    Usang, M. D.; Hamzah, N. S.; J. B., Abi M.; M. Z., M. Rawi; Abu, M. P.

    2014-02-01

    ORIGEN 2.2 are employed to obtain data regarding γ source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel.

  4. TRIGA MARK-II source term

    SciTech Connect

    Usang, M. D. Hamzah, N. S. Abi, M. J. B. Rawi, M. Z. M. Rawi Abu, M. P.

    2014-02-12

    ORIGEN 2.2 are employed to obtain data regarding γ source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel.

  5. TRIGA spent-fuel storage criticality analysis

    SciTech Connect

    Ravnik, M.; Glumac, B.

    1996-06-01

    A criticality safety analysis of a pool-type storage for spent TRIGA Mark II reactor fuel is presented. Two independent computer codes are applied: the MCNP Monte Carlo code and the WIMS lattice cell code. Two types of fuel elements are considered: standard fuel elements with 12 wt% uranium concentration and FLIP fuel elements. A parametric study of spent-fuel storage lattice pitch, fuel element burnup, and water density is presented. Normal conditions and postulated accident conditions are analyzed. A strong dependence of the multiplication factor on the distance between the fuel elements and on the effective water density is observed. A multiplication factor <1 may be expected for an infinite array of fuel rods at center-to-center distances >6.5 cm, regardless of the fuel element type and burnup. At shorter distances, the subcriticality can be ensured only by adding absorbers to the array of fuel rods even if the fuel rods were burned to {approximately}20% burnup. The results of both codes agree well for normal conditions. The results show that WIMS may be used as a complement to the Monte Carlo code in some parts of the criticality analysis.

  6. Assessment of the Optic Nerve Head Parameters Using Heidelberg Retinal Tomography III in Preterm Children

    PubMed Central

    Alshaarawi, Salem; Shatriah, Ismail; Zunaina, Embong; Wan Hitam, Wan Hazabbah

    2014-01-01

    Background Variations in optic nerve head morphology and abnormal retinal vascular pattern have been described in preterm children using digital image analysis of fundus photograph, optical coherence tomograph and serial funduscopy. We aimed to compare the optic nerve head parameters in preterm and term Malay children using Heidelberg Retinal Tomograph III. Design A cross sectional study. Methodology/Principal Findings Thirty-two preterm Malay children who were born at up to 32 weeks postconception, and 32 term Malay children aged 8–16 years old were recruited into this cross sectional study, which was conducted in the Hospital Universiti Sains Malaysia, Malaysia from January to December 2011. Their optic nerves were scanned and analyzed using a Heidelberg Retinal Tomography (HRT) III (Heidelberg Engineering, Germany). Preterm children showed an increased rim volume (SD) (0.56 (0.26) vs 0.44 (0.18) mm3, respectively), smaller cup shape (SD) (0.18 (0.07) vs 0.25 (0.06) mm, respectively), increased height variation contour (SD) (0.44 (0.14) vs 0.35 (0.08) mm, respectively), and increased cup depth (SD) (0.24 (0.11) vs 0.17 (0.05) mm3, respectively) when compared to their normal peers (p<0.05). There were no significant differences in the mean disc area, cup area, cup to disc ratio or rim area between the preterm and term children (p>0.05) in our study. Conclusions/Significance Preterm children exhibit different characteristics of optic nerve head parameters with HRT III analysis. Increased cup depth in preterm children suggests a need for close observation and monitoring. It may raise suspicion of pediatric glaucoma when proper documentation of intraocular pressure and clinical funduscopy are unsuccessful in uncooperative children. PMID:24551076

  7. Evolution of liver transplantation at the University of Heidelberg: interventions influencing patient referral.

    PubMed

    Schmied, Bruno Martin; Mehrabi, Arianeb; Schallert, Claudia; Schemmer, Peter; Sauer, Peter; Encke, Jens; Uhl, Waldemar; Friess, Helmut; Kraus, Thomas W; Büchler, Markus W; Schmidt, Jan

    2005-09-27

    In Heidelberg, liver transplantation was first performed in 1987. In this article, we report our experience with an interdisciplinary approach (intervention) to improve the internal and external acceptance of the liver transplantation program. Formation of a transplant team and interdisciplinary standard setting of pre-, peri-, and postoperative protocols significantly stimulated this process. Involvement of the referring doctors in patient's treatment by transferring competencies enhanced patients referral to our center and increased the numbers of patients on the waiting list, an indispensable factor for organ allocation by Eurotransplant and transplantation. Involvement of patient organizations increased patient acceptance in the program. PMID:16286894

  8. [The Heidelberg trichina dispute. A parasitologic episode from the year 1840].

    PubMed

    Giese, C

    1996-01-01

    Since the initial zoological description of "Trichina spiralis" (later renamed "Trichinella spiralis") by Owen in 1835 several other scientists had observed trichinas in human muscles, when an inglorious dispute about priorities arose between the anatomists Kobelt and Bischoff at the Heidelberg University in 1840 because of one of those findings. The genesis of trichinosis was only to be explained in 1860 by Zenker, while Bischoff, who was among the leading 19th century embryologists, then still believed in a "generatio spontanea" as it has been described in the context of the chronological outline of the "trichina dispute". PMID:8765543

  9. Extended-Spectrum Cephalosporin-Resistant Salmonella enterica serovar Heidelberg Strains, the Netherlands(1).

    PubMed

    Liakopoulos, Apostolos; Geurts, Yvon; Dierikx, Cindy M; Brouwer, Michael S M; Kant, Arie; Wit, Ben; Heymans, Raymond; van Pelt, Wilfrid; Mevius, Dik J

    2016-07-01

    Extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg strains (JF6X01.0022/XbaI.0251, JF6X01.0326/XbaI.1966, JF6X01.0258/XbaI.1968, and JF6X01.0045/XbaI.1970) have been identified in the United States with pulsed-field gel electrophoresis. Our examination of isolates showed introduction of these strains in the Netherlands and highlight the need for active surveillance and intervention strategies by public health organizations. PMID:27314180

  10. Extended-Spectrum Cephalosporin-Resistant Salmonella enterica serovar Heidelberg Strains, the Netherlands1

    PubMed Central

    Geurts, Yvon; Dierikx, Cindy M.; Brouwer, Michael S.M.; Kant, Arie; Wit, Ben; Heymans, Raymond; van Pelt, Wilfrid; Mevius, Dik J.

    2016-01-01

    Extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg strains (JF6X01.0022/XbaI.0251, JF6X01.0326/XbaI.1966, JF6X01.0258/XbaI.1968, and JF6X01.0045/XbaI.1970) have been identified in the United States with pulsed-field gel electrophoresis. Our examination of isolates showed introduction of these strains in the Netherlands and highlight the need for active surveillance and intervention strategies by public health organizations. PMID:27314180

  11. Transmissible Plasmid Containing Salmonella enterica Heidelberg Isolates Modulate Cytokine Production During Early Stage of Interaction with Intestinal Epithelial Cells.

    PubMed

    Gokulan, Kuppan; Khare, Sangeeta; Williams, Katherine; Foley, Steven L

    2016-08-01

    The variation in cytokine production during bacterial invasion of human intestinal epithelial cells (IECs) is a contributing factor for progression of the infection. A few Salmonella enterica Heidelberg strains isolated from poultry products harbor transmissible plasmids (TPs), including those that encode a type-IV secretion system. Earlier, we showed that these TPs are responsible for increased virulence during infection. This study examines the potential role of these TPs in cytokine production in IECs. This study showed that S. Heidelberg strains containing TPs (we refer as virulent strains) caused decreased interleukin (IL)-10 production in IECs after 1 h infection. The virulent strains induced a high level of tumor necrosis factor-α production under identical conditions. The virulent strains of S. Heidelberg also altered the production of IL-2, IL-17, and granulocyte macrophage colony-stimulating factor compared to an avirulent strain. As a part of infection, bacteria cross the epithelial barrier and encounter intestinal macrophages. Hence, we examined the cytotoxic mechanism of strains of S. Heidelberg in macrophages. Scanning electron microscopy showed cell necrosis occurs during the early stage of infection. In conclusion, virulent S. Heidelberg strains were able to modify the host cytokine profile during the early stages of infection and also caused necrosis in macrophages. PMID:27082282

  12. Heidelberg standard examination” and “Heidelberg standard procedures” – Development of faculty-wide standards for physical examination techniques and clinical procedures in undergraduate medical education

    PubMed Central

    Nikendei, C.; Ganschow, P.; Groener, J. B.; Huwendiek, S.; Köchel, A.; Köhl-Hackert, N.; Pjontek, R.; Rodrian, J.; Scheibe, F.; Stadler, A.-K.; Steiner, T.; Stiepak, J.; Tabatabai, J.; Utz, A.; Kadmon, M.

    2016-01-01

    The competent physical examination of patients and the safe and professional implementation of clinical procedures constitute essential components of medical practice in nearly all areas of medicine. The central objective of the projects “Heidelberg standard examination” and “Heidelberg standard procedures”, which were initiated by students, was to establish uniform interdisciplinary standards for physical examination and clinical procedures, and to distribute them in coordination with all clinical disciplines at the Heidelberg University Hospital. The presented project report illuminates the background of the initiative and its methodological implementation. Moreover, it describes the multimedia documentation in the form of pocketbooks and a multimedia internet-based platform, as well as the integration into the curriculum. The project presentation aims to provide orientation and action guidelines to facilitate similar processes in other faculties. PMID:27579354

  13. Nationwide outbreak of multidrug-resistant Salmonella Heidelberg infections associated with ground turkey: United States, 2011.

    PubMed

    Routh, J A; Pringle, J; Mohr, M; Bidol, S; Arends, K; Adams-Cameron, M; Hancock, W T; Kissler, B; Rickert, R; Folster, J; Tolar, B; Bosch, S; Barton Behravesh, C; Williams, I T; Gieraltowski, L

    2015-11-01

    On 23 May 2011, CDC identified a multistate cluster of Salmonella Heidelberg infections and two multidrug-resistant (MDR) isolates from ground turkey retail samples with indistinguishable pulsed-field gel electrophoresis patterns. We defined cases as isolation of outbreak strains in persons with illness onset between 27 February 2011 and 10 November 2011. Investigators collected hypothesis-generating questionnaires and shopper-card information. Food samples from homes and retail outlets were collected and cultured. We identified 136 cases of S. Heidelberg infection in 34 states. Shopper-card information, leftover ground turkey from a patient's home containing the outbreak strain and identical antimicrobial resistance profiles of clinical and retail samples pointed to plant A as the source. On 3 August, plant A recalled 36 million pounds of ground turkey. This outbreak increased consumer interest in MDR Salmonella infections acquired through United States-produced poultry and played a vital role in strengthening food safety policies related to Salmonella and raw ground poultry. PMID:25865382

  14. Salmonella heidelberg enteritis and bacteremia. An epidemic on two pediatric wards.

    PubMed

    Rice, P A; Craven, C; Wells, J G

    1976-04-01

    Symptomatic infection with Salmonella heidelberg developed in 55 children after their admission to the pediatric wards of two adjacent hospiatls in San Juan, Puerto Rico. Many of these children had been hospitalized for the treatment of diarrhea of unidentified etiology. In 25 of these patients, Salmonella bacteremia was documented. Five had clinically unsuspected and untreated bacteremia with no evidence of complications during the follow-up period of four and a half months. The remaining 30 had "standard" symptomatic infection due to S. heidelberg. Eight children died; four of these proved to be bacteremic. The index patient, who also introduced the infection into one of the hospitals, was identified. Person to person spread perpetuated the outbreak within and between the two hospitals for nearly four months. Although neonates with salmonellosis had a higher rate of bacteremia than other children, no other specific predisposing factors for Salmonella bacteremia were identified. Laboratory studies of the epidemic strain revealed neither invasive nor enterotoxic properties of the organisms, nor enhanced virulence in laboratory mice. Cohort nursing and isolation of patients with positive cultures halted the epidemic. Nontyphoid Salmonella bacteremia, sometimes clinically unsuspected and self-limited, should be recognized as a frequent accompaniment of Salmonella enteritis in young hospitalized children. PMID:1274984

  15. Technical and dosimetric aspects of the total skin electron beam technique implemented at Heidelberg University Hospital

    PubMed Central

    Hensley, Frank W.; Major, Gerald; Edel, Carolin; Hauswald, Henrik; Bischof, Marc

    2013-01-01

    Aim To give a technical description and present the dosimetric proporties of the total skin electron beam technique implemented at Heidelberg University Hospital. Background Techniques used for total skin electron beam irradiation were developed as early as in the 1960s to 1980s and have, since then, hardly changed. However, new measurements of the established methods allow deeper insight into the dose distributions and reasons for possible deviations from uniform dose. Materials and methods The TSEI technique applied at Heidelberg University Hospital since 1992 consists of irradiating the patient with a superposition of two beams of low energy electrons at gantry angles of 72° and 108° while he is rotating in a standing position on a turntable at 370 cm distance from the accelerator. The energy of the electron beam is degraded to 3.9 MeV by passing through an attenuator of 6 mm of Perspex. A recent re-measurement of the dose distribution is presented using modern dosimetry tools like a linear array of ionization chambers in combination with established methods like thermoluminescent detectors and film dosimetry. Results The measurements show a strong dependence of dose uniformity on details of the setup like gantry angles. Conclusions Dose uniformity of −4/+8% to the majority of the patient's skin can be achieved, however, for the described rotational technique overdoses up to more than 20% in small regions seem unavoidable. PMID:24936332

  16. Outbreak of Salmonella Heidelberg infections linked to a single poultry producer -- 13 states, 2012-2013.

    PubMed

    2013-07-12

    In June 2012, the Oregon Health Authority and the Washington State Department of Health noted an increase in the number of Salmonella enterica serotype Heidelberg clinical isolates sharing an identical pulsed-field gel electrophoresis (PFGE) pattern. In 2004, this pattern had been linked to chicken from Foster Farms by the Washington State Department of Health; preliminary 2012 interviews with infected persons also indicated exposure to Foster Farms chicken. On August 2, 2012, CDC's PulseNet* detected a cluster of 19 Salmonella Heidelberg clinical isolates matching the outbreak pattern. This report summarizes the investigation by CDC, state and local health departments, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA-FSIS), and the Food and Drug Administration (FDA) and reinforces the importance of safe food handling to prevent illness. A total of 134 cases from 13 states were identified, including 33 patients who were hospitalized. This multifaceted investigation used standard epidemiologic and laboratory data along with patient shopper card purchase information, and PFGE data from the retail meat component of the National Antimicrobial Resistance Monitoring System (NARMS)†, a relatively novel tool in outbreak investigation, to link the outbreak strain to chicken from Foster Farms. PMID:23842445

  17. ORIGEN2 calculations supporting TRIGA irradiated fuel data package

    SciTech Connect

    Schmittroth, F.A.

    1996-09-20

    ORIGEN2 calculations were performed for TRIGA spent fuel elements from the Hanford Neutron Radiography Facility. The calculations support storage and disposal and results include mass, activity,and decay heat. Comparisons with underwater dose-rate measurements were used to confirm and adjust the calculations.

  18. 78 FR 26811 - Dow Chemical Company, Dow TRIGA Research Reactor; License Renewal for the Dow Chemical TRIGA...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ...) published a notice in the Federal Register on July 20, 2012 (77 FR 42771), ``License Renewal for the Dow...: I. Correction In the Federal Register (FR) of July 20, 2012, in FR Doc. 2012- 17733, on page 42772... COMMISSION Dow Chemical Company, Dow TRIGA Research Reactor; License Renewal for the Dow Chemical...

  19. Estimation of gastric residence time of the Heidelberg capsule in humans: effect of varying food composition

    SciTech Connect

    Mojaverian, P.; Ferguson, R.K.; Vlasses, P.H.; Rocci, M.L. Jr.; Oren, A.; Fix, J.A.; Caldwell, L.J.; Gardner, C.

    1985-08-01

    In animal and human studies, the gastric emptying of large (greater than 1 mm) indigestible solids is due to the activity of the interdigestive migrating myoelectric complex. The gastric residence time (GRT) of an orally administered, nondigestible, pH-sensitive, radiotelemetric device (Heidelberg capsule) was evaluated in three studies in healthy volunteers. In 6 subjects, the GRT of the Heidelberg capsule was compared with the half-emptying time (t1/2) of diethylenetriaminepentaacetic acid labeled with technetium 99m after a 4-ml/kg liquid fatty meal. The mean (+/-SD) GRT (4.3 +/- 1.4 h) was significantly (p less than 0.001) longer than the mean t1/2 (1.1 +/- 0.3 h); the GRT was prolonged compared with the t1/2 in each subject. In a randomized, crossover trial in 10 subjects, frequent feeding caused a dramatic prolongation in mean GRT of the capsule compared with the fasting state (greater than 14.5 vs. 0.5 h, p less than 0.005). In another crossover study in 6 subjects, the GRT of the capsule was evaluated after an overnight fast, a standard breakfast including solid food, and a liquid meal (i.e., 200 ml of diluted light cream). The mean GRT was 2.6 +/- 0.9 h after the liquid meal vs. 1.2 +/- 0.8 h after fasting (p less than 0.025). The mean GRT after the breakfast was 4.8 +/- 1.5 h, which was significantly greater than that after fasting (p less than 0.001) and after the liquid meal (p less than 0.01). These data suggest that the GRT of the Heidelberg capsule is a marker of the interdigestive migrating myoelectric complex in humans, the interdigestive migrating myoelectric complex can be markedly delayed by frequent feedings with solids, and the interdigestive migrating myoelectric complex is delayed by both liquid and solid meals.

  20. Compact soft x-ray spectrometer for plasma diagnostics at the Heidelberg Electron Beam Ion Trap

    SciTech Connect

    Lapierre, A.; Crespo Lopez-Urrutia, J. R.; Baumann, T. M.; Epp, S. W.; Gonchar, A.; Gonzalez Martinez, A. J.; Liang, G.; Rohr, A.; Soria Orts, R.; Simon, M. C.; Tawara, H.; Versteegen, R.; Ullrich, J.

    2007-12-15

    A compact flat-field soft x-ray grazing-incidence grating spectrometer equipped with a cryogenically cooled back-illuminated charge-coupled device camera was built and implemented at the Heidelberg Electron Beam Ion Trap. The instrument spans the spectral region from 1 to 37 nm using two different gratings. In slitless operation mode, it directly images a radiation source, in this case ions confined in an electron beam ion trap, with high efficiency and reaching hereby a resolving power of {lambda}/{delta}{lambda} congruent with 130 at 2 nm and of {lambda}/{delta}{lambda} congruent with 600 at 28 nm. Capable of automatized operation, its low noise and excellent stability make it an ideal instrument not only for spectroscopic diagnostics requiring wide spectral coverage but also for precision wavelength measurements.

  1. Dependence of optic disc parameters on disc area according to Heidelberg Retina Tomograph: Part II.

    NASA Astrophysics Data System (ADS)

    Machekhin, V.; Manaenkova, G.; Bondarenko, O.

    2007-05-01

    With the help of Heidelberg Retina Tomograph (HRT-II) optic disc parameters in 211 eyes of 115 healthy patients with refraction Em +/- 3,0 D and 96 eyes of 72 patients with myopia 3,5-14,0 D without any signs of glaucoma were studied. Analysis of optic disc parameters were carried out in 5 groups of patients according to disc area: less than 1,5 mm2, 1,5- 2,5 mm2, 2,5-3,0 mm2, 3,0-3,5 mm2 and more than 3,5 mm2. An accurate depending on disc area was revealed for all optic disc parameters in all sectors, which was manifested by increasing cup disc and rim disc (area and volume) and other parameters. We consider it is necessary to use the proper tables for right interpretation of received data for early diagnosis of glaucoma.

  2. Bounds on new Majoron models from the Heidelberg-Moscow experiment

    SciTech Connect

    Guenther, M.; Hellmig, J.; Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V.; Maier, B.; Paes, H.; Petry, F.; Ramachers, Y.; Strecker, H.; Voellinger, M.; Balysh, A.; Belyaev, S.T.; Demehin, A.; Gurov, A.; Kondratenko, I.; Kotelnikov, D.; Lebedev, V.I.; Mueller, A.

    1996-09-01

    In recent years several new Majoron models were invented to avoid the shortcomings of the ordinary models while leading to observable decay rates in double {beta} experiments. We give the first experimental half-life bounds on double {beta} decays with new Majoron emission and derive bounds on the effective neutrino-Majoron couplings from the data of the {sup 76}Ge Heidelberg-Moscow experiment. While stringent half-life limits for all decay modes and the coupling constants of the ordinary models were obtained, small matrix elements and phase space integrals result in much weaker limits on the effective coupling constants of the new Majoron models. {copyright} {ital 1996 The American Physical Society.}

  3. Optics and experimental resolution of the Heidelberg slit-scan flow fluorometer

    NASA Astrophysics Data System (ADS)

    Hausmann, Michael; Wickert, Burkhard; Vogel, Michael; Schurwanz, Michael; Doelle, Juergen; Wolf, Dietmar; Aldinger, Klaus; Cremer, Christoph G.

    1996-01-01

    Slit-scan flow fluorometry is a laser-technological approach for accelerated screening and sorting of fluorescence labelled metaphase chromosomes. Details of the optics of the Heidelberg slit-scan sorter are presented. In a fluid stream the fluorescence labelled chromosomes rapidly pass one at a time by a scanning laser beam. The laser can be focused by a less complex optic consisting of only a few commercially available lenses. The laser intensity distribution around the focus was measured for 488 nm for two lens configurations. Although the light distribution obtained by such an optic is normally not aberration free, the requirements of a 'ribbonlike' shape in the center of the fluid stream can be fulfilled. Since the chromosomes are oriented perpendicularly to the laser beam by hydrodynamic focusing of the fluid stream, the fluorescence intensity along the chromosome axis can be measured time (equals spatially) resolved. According to their intensity profiles the chromosomes can be classified. Signal processing of the profiles can be performed in less than 600 microseconds, so that in the order of hundred chromosomes per second can be sorted out by a computer controlled electro-acoustic sorting unit. The final spatial resolution of a slit-scan flow sorter is not only affected by the focusing optics of the laser but also by the fluid stream, the detection optics and electronics, as well as by the computer analysis algorithm. Calculations often consider only the optics under ideal conditions. Here, a method is shown how to estimate the overall resolution of a slit-scan flow fluorometer experimentally. According to this criterion the resolution of the Heidelberg slit-scan sorter for 488 nm fluorescence excitation was estimated to be 2.4 micrometer in its basic optical configuration and 1.7 micrometer with additional correction of chromatic aberration effects.

  4. Maximizing time from the constraining European Working Time Directive (EWTD): The Heidelberg New Working Time Model

    PubMed Central

    2014-01-01

    Background The introduction of the European Working Time Directive (EWTD) has greatly reduced training hours of surgical residents, which translates into 30% less surgical and clinical experience. Such a dramatic drop in attendance has serious implications such compromised quality of medical care. As the surgical department of the University of Heidelberg, our goal was to establish a model that was compliant with the EWTD while avoiding reduction in quality of patient care and surgical training. Methods We first performed workload analyses and performance statistics for all working areas of our department (operation theater, emergency room, specialized consultations, surgical wards and on-call duties) using personal interviews, time cards, medical documentation software as well as data of the financial- and personnel-controlling sector of our administration. Using that information, we specifically designed an EWTD-compatible work model and implemented it. Results Surgical wards and operating rooms (ORs) were not compliant with the EWTD. Between 5 pm and 8 pm, three ORs were still operating two-thirds of the time. By creating an extended work shift (7:30 am-7:30 pm), we effectively reduced the workload to less than 49% from 4 pm and 8 am, allowing the combination of an eight-hour working day with a 16-hour on call duty; thus, maximizing surgical resident training and ensuring patient continuity of care while maintaining EDTW guidelines. Conclusion A precise workload analysis is the key to success. The Heidelberg New Working Time Model provides a legal model, which, by avoiding rotating work shifts, assures quality of patient care and surgical training. PMID:25984433

  5. Cortical reorganization in recent-onset tinnitus patients by the Heidelberg Model of Music Therapy

    PubMed Central

    Krick, Christoph M.; Grapp, Miriam; Daneshvar-Talebi, Jonas; Reith, Wolfgang; Plinkert, Peter K.; Bolay, Hans Volker

    2015-01-01

    Pathophysiology and treatment of tinnitus still are fields of intensive research. The neuroscientifically motivated Heidelberg Model of Music Therapy, previously developed by the German Center for Music Therapy Research, Heidelberg, Germany, was applied to explore its effects on individual distress and on brain structures. This therapy is a compact and fast application of nine consecutive 50-min sessions of individualized therapy implemented over 1 week. Clinical improvement and long-term effects over several years have previously been published. However, the underlying neural basis of the therapy's success has not yet been explored. In the current study, the therapy was applied to acute tinnitus patients (TG) and healthy active controls (AC). Non-treated patients were also included as passive controls (PTC). As predicted, the therapeutic intervention led to a significant decrease of tinnitus-related distress in TG compared to PTC. Before and after the study week, high-resolution MRT scans were obtained for each subject. Assessment by repeated measures design for several groups (Two-Way ANOVA) revealed structural gray matter (GM) increase in TG compared to PTC, comprising clusters in precuneus, medial superior frontal areas, and in the auditory cortex. This pattern was further applied as mask for general GM changes as induced by the therapy week. The therapy-like procedure in AC also elicited similar GM increases in precuneus and frontal regions. Comparison between structural effects in TG vs. AC was calculated within the mask for general GM changes to obtain specific effects in tinnitus patients, yielding GM increase in right Heschl's gyrus, right Rolandic operculum, and medial superior frontal regions. In line with recent findings on the crucial role of the auditory cortex in maintaining tinnitus-related distress, a causative relation between the therapy-related GM alterations in auditory areas and the long-lasting therapy effects can be assumed. PMID:25745385

  6. Cortical reorganization in recent-onset tinnitus patients by the Heidelberg Model of Music Therapy.

    PubMed

    Krick, Christoph M; Grapp, Miriam; Daneshvar-Talebi, Jonas; Reith, Wolfgang; Plinkert, Peter K; Bolay, Hans Volker

    2015-01-01

    Pathophysiology and treatment of tinnitus still are fields of intensive research. The neuroscientifically motivated Heidelberg Model of Music Therapy, previously developed by the German Center for Music Therapy Research, Heidelberg, Germany, was applied to explore its effects on individual distress and on brain structures. This therapy is a compact and fast application of nine consecutive 50-min sessions of individualized therapy implemented over 1 week. Clinical improvement and long-term effects over several years have previously been published. However, the underlying neural basis of the therapy's success has not yet been explored. In the current study, the therapy was applied to acute tinnitus patients (TG) and healthy active controls (AC). Non-treated patients were also included as passive controls (PTC). As predicted, the therapeutic intervention led to a significant decrease of tinnitus-related distress in TG compared to PTC. Before and after the study week, high-resolution MRT scans were obtained for each subject. Assessment by repeated measures design for several groups (Two-Way ANOVA) revealed structural gray matter (GM) increase in TG compared to PTC, comprising clusters in precuneus, medial superior frontal areas, and in the auditory cortex. This pattern was further applied as mask for general GM changes as induced by the therapy week. The therapy-like procedure in AC also elicited similar GM increases in precuneus and frontal regions. Comparison between structural effects in TG vs. AC was calculated within the mask for general GM changes to obtain specific effects in tinnitus patients, yielding GM increase in right Heschl's gyrus, right Rolandic operculum, and medial superior frontal regions. In line with recent findings on the crucial role of the auditory cortex in maintaining tinnitus-related distress, a causative relation between the therapy-related GM alterations in auditory areas and the long-lasting therapy effects can be assumed. PMID:25745385

  7. [From stand-alone solution to longitudinal communication curriculum--development and implementation at the Faculty of Medicine in Heidelberg].

    PubMed

    Sator, Marlene; Jünger, Jana

    2015-05-01

    At the Faculty of Medicine in Heidelberg, implementation of an interdisciplinary longitudinal curriculum was started in 2001 with the goal of achieving sustained promotion of communicative and clinical competences. The aim of this paper is to describe the development and implementation of Heidelberg's longitudinal communication curriculum. Furthermore, innovative aspects and strategies are discussed. The methodological approaches for development and implementation were Kern's "Six-step Approach" and a SWOT analysis. The process resulted in an innovative communication curriculum that starts with an integrated curriculum for developing clinical and communicative competence in the pre-clinical phase and continues in the clinical phase with medical communication and interactive training. Satisfaction with the communication curriculum and its effectiveness were rated highly by students. Residents who had graduated from Faculty of Medicine in Heidelberg rated the extent to which they had communicative competencies at the time of their graduation at their disposal significantly higher than residents who had graduated from the other 4 medical faculties in Baden-Württemberg. The experiences gained in Heidelberg can be applied by other faculties. PMID:25941988

  8. TRIGA reactor facility at the Armed Forces Radiobiology Research Institute: A simplified technical description. revision. Technical report

    SciTech Connect

    Moore, M.L.

    1994-01-01

    This publication provides a simplified technical description of the TRIGA research reactor at AFRRI. Topics covered include general principles of reactor operation and a description of the TRIGA reactor and its unique features.

  9. Identification of leaking TRIGA fuel elements

    SciTech Connect

    Bennion, John S.; Crawford, Kevan C.; Gansauge, Todd C.; Sandquist, Gary M.

    1990-07-01

    The 100 kW TRIGA Mark I Nuclear Reactor at the University of Utah achieved initial criticality in October, 1975. Previously irradiated fuel consisting of stainless-steel- and aluminum-clad elements was acquired from the University of Arizona and the U.S. Army's Harry Diamond Laboratories in Adelphi, Maryland. Past core configurations have been comprised of both types of fuel with the aluminum-clad elements normally restricted to outer hexagonal rings of the core to provide a large safety margin between actual fuel temperature and limits set forth in the facility Technical Specifications. On October 20, 1987, trace cesium-137 contamination was discovered during routine analysis of the ion-exchange resin in the demineralizer circuit. The presence of Cs-137 indicated a possible clad defect resulting in the leakage of fission products. Reactor operations were allowed only to assist in identifying the source of the leakage. Pool water samples obtained following a two-hour operation at full power were spectroscopically analyzed and found to contain very small amounts of short-lived noble gases (e.g., Kr-85m, Kr-87, Kr-88, Xe-138) and their decay daughter products (e.g., Rb-88, Cs-138). Samples of the gaseous effluent from the facility collected in activated charcoal canisters showed no indication of fission product contamination. The small amount of activity released to the pool water suggested that a single defective element was responsible for the leakage. The instrumented fuel element and the aluminum-clad fuel were initially suspected as sources of the leakage. A simple scheme was devised to identify the defective element by exchanging four or five elements from the core with fuel in storage and then operating the reactor at 90 kW power for two hours. A pool water sample was then taken and analyzed to determine if the damaged element had been removed from the core. This process was repeated several times until all of the aluminum-clad fuel and several stainless

  10. High-Precision Mass Measurements At TRIGA-TRAP

    NASA Astrophysics Data System (ADS)

    Smorra, C.; Beyer, T.; Blaum, K.; Block, M.; Eberhardt, K.; Eibach, M.; Herfurth, F.; Ketelaer, J.; Knuth, K.; Nörtershäuser, W.; Nagy, Sz.

    2010-04-01

    In order to study neutron-rich nuclides far from the valley of stability as well as long-lived actinoids the double Penning-trap mass spectrometer TRIGA-TRAP has been recently installed at the research reactor TRIGA Mainz. Short-lived neutron-rich fission products are produced by thermal neutron-induced fission of an actinoid target installed close to the reactor core. A helium gas-jet system with carbon aerosol particles is used to extract the fission products to the experiment. The Penning trap system has already been commissioned. Off-line mass measurements are routinely performed using a recently developed laser ablation ion source, and the gas-jet system has been tested. An overview of the experiment and current status will be given.

  11. High-Precision Mass Measurements At TRIGA-TRAP

    SciTech Connect

    Smorra, C.; Eibach, M.; Beyer, T.; Blaum, K.; Block, M.; Herfurth, F.; Eberhardt, K.; Ketelaer, J.; Knuth, K.; Noertershaeuser, W.; Nagy, Sz.

    2010-04-30

    In order to study neutron-rich nuclides far from the valley of stability as well as long-lived actinoids the double Penning-trap mass spectrometer TRIGA-TRAP has been recently installed at the research reactor TRIGA Mainz. Short-lived neutron-rich fission products are produced by thermal neutron-induced fission of an actinoid target installed close to the reactor core. A helium gas-jet system with carbon aerosol particles is used to extract the fission products to the experiment. The Penning trap system has already been commissioned. Off-line mass measurements are routinely performed using a recently developed laser ablation ion source, and the gas-jet system has been tested. An overview of the experiment and current status will be given.

  12. Operational characteristics of the new 12 wt% TRIGA fuel

    SciTech Connect

    Boyle, P.; Levine, S.H.

    1997-12-01

    It has been reported that an instrumented TRIGA fuel element, I-15, had higher than normal fuel temperatures. As shown in Fig. 1, one of the newest instrumented fuel elements, I-17, has fuel temperatures equal to/and or higher than that of I-15. Another new fuel element, I-16, behaves similarly to I-17, and this is before they have been pulsed (the first pulses increase the steady-state temperature). Thus, there is a significant increase in the measured fuel temperatures of the newest TRIGA fuel received from General Atomics. They are estimated to measure fuel temperatures that exceed 600{degrees}C when in the B-ring at 1 MW at their beginning of life (BOL). The purpose of this summary is to report on the measurements performed with these new fuel elements and to describe the effect that the new information is having on the future fuel management plans for the Penn State Breazeale Research Reactor.

  13. Implementation of an aerodynamic lens for TRIGA-SPEC

    NASA Astrophysics Data System (ADS)

    Grund, J.; Düllmann, Ch. E.; Eberhardt, K.; Nagy, Sz.; van de Laar, J. J. W.; Renisch, D.; Schneider, F.

    2016-06-01

    We report on the optimization of the gas-jet system employed to couple the TRIGA-SPEC experiment to the research reactor TRIGA Mainz. CdI2 aerosol particles suspended in N2 as carrier gas are used for an effective transport of fission products from neutron induced 235 U fission from the target chamber to a surface ion source. Operating conditions of the gas-jet were modified to enable the implementation of an aerodynamic lens, fitting into the limited space available in front of the ion source. The lens boosts the gas-jet efficiency by a factor of 4-10. The characterization of the gas-jet system as well as the design of the aerodynamic lens and efficiency studies are presented and discussed.

  14. TRIGA FUEL PHASE I AND II CRITICALITY CALCULATION

    SciTech Connect

    L. Angers

    1999-11-23

    The purpose of this calculation is to characterize the criticality aspect of the codisposal of TRIGA (Training, Research, Isotopes, General Atomic) reactor spent nuclear fuel (SNF) with Savannah River Site (SRS) high-level waste (HLW). The TRIGA SNF is loaded into a Department of Energy (DOE) standardized SNF canister which is centrally positioned inside a five-canister defense SRS HLW waste package (WP). The objective of the calculation is to investigate the criticality issues for the WP containing the five SRS HLW and DOE SNF canisters in various stages of degradation. This calculation will support the analysis that will be performed to demonstrate the viability of the codisposal concept for the Monitored Geologic Repository (MGR).

  15. Status of the TRIGA shipments to the INEEL from Asia

    SciTech Connect

    Tyacke, M.; George, W.; Petrasek, A.; Stump, R.C.; Patterson, J.

    1997-10-09

    This paper will report on preparations being made for returning Training, Research, Isotope, General Atomics (TRIGA) foreign research reactor (FRR) spent fuel from South Korea and Indonesia to the Idaho National Engineering and Environmental Laboratory (INEEL). The roles of US Department of Energy, INEEL, and NAC International in implementing a safe shipment are provided. Special preparations necessitated by making a shipment through a west coast port of the US to the INEEL will be explained. The institutional planning and actions needed to meet the unique political and operational environment for making a shipment from Asia to INEEL will be discussed. Facility preparation at both the INEEL and the FRRs is discussed. Cask analysis needed to properly characterize the various TRIGA configurations, compositions, and enrichments is discussed. Shipping preparations will include an explanation of the integrated team of spent fuel transportation specialists, and shipping resources needed to retrieve the fuel from foreign research reactor sites and deliver it to the INEEL.

  16. Computational analysis of irradiation facilities at the JSI TRIGA reactor.

    PubMed

    Snoj, Luka; Zerovnik, Gašper; Trkov, Andrej

    2012-03-01

    Characterization and optimization of irradiation facilities in a research reactor is important for optimal performance. Nowadays this is commonly done with advanced Monte Carlo neutron transport computer codes such as MCNP. However, the computational model in such calculations should be verified and validated with experiments. In the paper we describe the irradiation facilities at the JSI TRIGA reactor and demonstrate their computational characterization to support experimental campaigns by providing information on the characteristics of the irradiation facilities. PMID:22154389

  17. TRIGA: Telecommunications Protocol Processing Subsystem Using Reconfigurable Interoperable Gate Arrays

    NASA Technical Reports Server (NTRS)

    Pang, Jackson; Pingree, Paula J.; Torgerson, J. Leigh

    2006-01-01

    We present the Telecommunications protocol processing subsystem using Reconfigurable Interoperable Gate Arrays (TRIGA), a novel approach that unifies fault tolerance, error correction coding and interplanetary communication protocol off-loading to implement CCSDS File Delivery Protocol and Datalink layers. The new reconfigurable architecture offers more than one order of magnitude throughput increase while reducing footprint requirements in memory, command and data handling processor utilization, communication system interconnects and power consumption.

  18. Temperature feedback of TRIGA MARK-II fuel

    NASA Astrophysics Data System (ADS)

    Usang, M. D.; Minhat, M. S.; Rabir, M. H.; M. Rawi M., Z.

    2016-01-01

    We study the amount of temperature feedback on reactivity for the three types of TRIGA fuel i.. ST8, ST12 and LEU fuel, are used in the TRIGA MARK II reactor in Malaysia Nuclear Agency. We employ WIMSD-5B for the calculation of kin f for a single TRIGA fuel surrounded by water. Typical calculations of TRIGA fuel reactivity are usually limited to ST8 fuel, but in this paper our investigation extends to ST12 and LEU fuel. We look at the kin f of our model at various fuel temperatures and calculate the amount reactivity removed. In one instance, the water temperature is kept at room temperature of 300K to simulate sudden reactivity increase from startup. In another instance, we simulate the sudden temperature increase during normal operation where the water temperature is approximately 320K while observing the kin f at various fuel temperatures. For accidents, two cases are simulated. The first case is for water temperature at 370K and the other is without any water. We observe that the higher Uranium content fuel such as the ST12 and LEU have much smaller contribution to the reactivity in comparison to the often studied ST8 fuel. In fact the negative reactivity coefficient for LEU fuel at high temperature in water is only slightly larger to the negative reactivity coefficient for ST8 fuel in void. The performance of ST8 fuel in terms of negative reactivity coefficient is cut almost by half when it is in void. These results are essential in the safety evaluation of the reactor and should be carefully considered when choices of fuel for core reconfiguration are made.

  19. Steady-State Axial Temperature and Flow Velocity in Triga Channel.

    Energy Science and Technology Software Center (ESTSC)

    2007-02-28

    Version 00 TRISTAN-IJS is a computer program for calculating steady-state axial temperature distribution and flow velocity through a vertical coolant channel in low power TRIGA reactor core, cooled by natural circulation. It is designed for steady-state thermohydraulic analysis of TRIGA research reactors operating at a low power level of 1-2 MW.

  20. An RFQ cooler and buncher for the TRIGA-SPEC experiment

    NASA Astrophysics Data System (ADS)

    Beyer, T.; Blaum, K.; Block, M.; Düllmann, Ch. E.; Eberhardt, K.; Eibach, M.; Frömmgen, N.; Geppert, C.; Gorges, C.; Grund, J.; Hammen, M.; Kaufmann, S.; Krieger, A.; Nagy, Sz.; Nörterhäuser, W.; Renisch, D.; Smorra, C.; Will, E.

    2014-01-01

    A linear Paul trap for cooling of ion beams, the former cooler for emittance elimination radiofrequency quadrupole (RFQ) at MISTRAL/ISOLDE, has been installed and commissioned at the TRIGA-SPEC experiment located at the research reactor TRIGA Mainz. It is connected to a hot-surface-ionization ion source and a subsequent mass separator for ionization and pre-separation of neutron-rich fission products as delivered from the reactor. The capability of accumulating and bunching ion beams has been implemented to provide low-emittance ion pulses of 250 ns width containing up to 106 ions. A technical description of the upgraded RFQ as well as its characterization with stable ions is presented. Its installation allows delivery of low-emittance ion bunches to the two branches of the TRIGA-SPEC experiment, namely TRIGA-TRAP and TRIGA-LASER.

  1. Proposed modification of an instrumented TRIGA fuel element so that it may be handled with a standard TRIGA fuel handling tool

    SciTech Connect

    Doane, Harry J.

    1992-07-01

    Instrumented fuel elements whose thermocouples are no longer functional are still a useful source of reactor fuel. Their usefulness is hampered somewhat by the extension tubing that must extend above water level to keep the thermocouple extension leads dry and to keep pool water from interacting with the gas tight lead seal which is made below the lower coupling in the extension tubing. This facility proposes to modify an instrumented TRIGA fuel element by removing the extension tubing at the lower coupling and attaching to it a top end fixture that is normally supplied with a standard TRIGA fuel element. This would then allow movement of the modified fuel element with a standard TRIGA fuel handling tool. This paper will present the considerations involved in performing this modification and the presenter will solicit any useful information that might be contributed by attendees of the TRIGA Owners' Conference. (author)

  2. A unified framework for glaucoma progression detection using Heidelberg Retina Tomograph images

    PubMed Central

    Belghith, Akram; Balasubramanian, Madhusudhanan; Bowd, Christopher; Weinreb, Robert N.; Zangwill, Linda M.

    2014-01-01

    Glaucoma, the second leading cause of blindness worldwide, is an optic neuropthy characterized by distinctive changes in the optic nerve head (ONH) and visual field. The detection of glaucomatous progression is one of the most important and most challenging aspects of primary open angle glaucoma (OAG) management. In this context, ocular imaging equipment is increasingly sophisticated, providing quantitative tools to measure structural changes in ONH topography, an essential element in determining whether the disease is getting worse. In particular, the Heidelberg Retina Tomograph (HRT), a confocal scanning laser technology, has been commonly used to detect glaucoma and monitor its progression. In this paper, we present a new framework for detection of glaucomatous progression using HRT images. In contrast to previous works that do not integrate a priori knowledge available in the images, particularly the spatial pixel dependency in the change detection map, the Markov Random Field is proposed to handle such dependency. To our knowledge, this is the first application of the Variational Expectation Maximization (VEM) algorithm for inferring topographic ONH changes in the glaucoma progression detection framework. Diagnostic performance of the proposed framework is compared to recently proposed methods of progression detection. PMID:24709053

  3. International outbreak investigation of Salmonella Heidelberg associated with in-flight catering.

    PubMed

    Rebolledo, J; Garvey, P; Ryan, A; O'Donnell, J; Cormican, M; Jackson, S; Cloak, F; Cullen, L; Swaan, C M; Schimmer, B; Appels, R W; Nygard, K; Finley, R; Sreenivasan, N; Lenglet, A; Gossner, C; McKeown, P

    2014-04-01

    Rapid and wide dispersal of passengers after flights makes investigation of flight-related outbreaks challenging. An outbreak of Salmonella Heidelberg was identified in a group of Irish travellers returning from Tanzania. Additional international cases sharing the same flight were identified. Our aim was to determine the source and potential vehicles of infection. Case-finding utilized information exchange using experts' communication networks and national surveillance systems. Demographic, clinical and food history information was collected. Twenty-five additional cases were identified from Ireland, The Netherlands, Norway, USA and Canada. We conducted a case-control study which indicated a significant association between illness and consumption of milk tart (OR 10.2) and an egg dish (OR 6) served on-board the flight. No food consumed before the flight was associated with illness. Cases from countries other than Ireland provided supplementary information that facilitated the identification of likely vehicles of infection. Timely, committed international collaboration is vital in such investigations. PMID:23890227

  4. [The primary radiotherapy of inoperable or recurrent pancreatic carcinoma--Heidelberg patients from 1982 to 1992].

    PubMed

    Latz, D; Schraube, P; Eble, M J

    1993-07-01

    Between 1982 and 1992, 34 patients with locally advanced or relapsed adenocarcinoma of the pancreas were treated at the Department of Radiotherapy in Heidelberg. 14 patients were treated with a combined radiochemotherapy with 5-FU, the other patients were irradiated alone. In all cases irradiation was done with high energy photons. 15 patients received an irradiation with doses between 30 and 44 Gy, and twelve patients between 45 and 66 Gy (median 50 Gy). Seven patients were treated intraoperatively during an exploration laparotomy with fast electrons (10 to 18 MeV, 15 to 20 Gy) and postoperatively with additional 30 to 41 Gy. The median survival of the patients treated with the higher doses or in combination with the IORT showed a significant advantage of nine vs. 2.9 months. There was no benefit in median survival for the patients treated with radiochemotherapy. In retrospective analysis of the percutaneous treated patient collective a pain relief was observed in nine patients. In the prospective treatment protocol of the IORT in 4/4 patients a pain relief was rapidly reached. PMID:8342111

  5. Electron cyclotron resonance ion source experience at the Heidelberg Ion Beam Therapy Center.

    PubMed

    Winkelmann, T; Cee, R; Haberer, T; Naas, B; Peters, A; Scheloske, S; Spädtke, P; Tinschert, K

    2008-02-01

    Radiotherapy with heavy ions is an upcoming cancer treatment method with to date unparalleled precision. It associates higher control rates particularly for radiation resistant tumor species with reduced adverse effects compared to conventional photon therapy. The accelerator beam lines and structures of the Heidelberg Ion Beam Therapy Center (HIT) have been designed under the leadership of GSI, Darmstadt with contributions of the IAP Frankfurt. Currently, the accelerator is under commissioning, while the injector linac has been completed. When the patient treatment begins in 2008, HIT will be the first medical heavy ion accelerator in Europe. This presentation will provide an overview about the project, with special attention given to the 14.5 GHz electron cyclotron resonance (ECR) ion sources in operation with carbon, hydrogen, helium, and oxygen, and the experience of one year of continuous operation. It also displays examples for beam emittances, measured in the low energy beam transport. In addition to the outlook of further developments at the ECR ion sources for a continuously stable operation, this paper focuses on some of the technical processings of the past year. PMID:18315121

  6. Low Energy Electron Cooling and Accelerator Physics for the Heidelberg CSR

    SciTech Connect

    Fadil, H.; Grieser, M.; Hahn, R. von; Orlov, D.; Schwalm, D.; Wolf, A.; Zajfman, D.

    2006-03-20

    The Cryogenic Storage Ring (CSR) is currently under construction at MPI-K in Heidelberg. The CSR is an electrostatic ring with a total circumference of about 34 m, straight section length of 2.5 m and will store ions in the 20 {approx} 300 keV energy range (E/Q). The cryogenic system in the CSR is expected to cool the inner vacuum chamber down to 2 K. The CSR will be equipped with an electron cooler which has also to serve as an electron target for high resolution recombination experiments. In this paper we present the results of numerical investigations of the CSR lattice with finite element calculations of the deflection and focusing elements of the ring. We also present a layout of the CSR electron cooler which will have to operate in low energy mode to cool 20 keV protons in the CSR, as well as numerical estimations of the cooling times to be expected with this device.

  7. Ultra-Cold Electron Beams for the Heidelberg TSR and CSR

    SciTech Connect

    Orlov, D. A.; Lestinsky, M.; Sprenger, F.; Schwalm, D.; Wolf, A.; Terekhov, A. S.

    2006-03-20

    A cold electron target with a cryogenic GaAs-photocathode electron source was developed for the Heidelberg Test Storage Ring. Two independent electron facilities (cooler and target) allow to separate cooling of the ion beam from target operation improving the quality of electron and ion beams. In addition a strong gain in the resolution was achieved with a help of a cryogenic photoelecron source providing dc electron currents up to 0.5 mA with an emission energy spread of about 10 meV. In first recombination measurements at the target, performed on HD +, H{sub 3}{sup +} and Sc18+, low energy resonant structures at milli-eV collision energies revealed unprecedented low transverse and longitudinal electron temperatures of about 0.5 meV and 0.025 meV, respectively. The photocathode source will be also used to provide cold beams for electron cooling of low-energy ions stored at the electrostatic Cryogenic Storage Ring which will be built at MPIK. The perspectives of photocathode-driven electron coolers operating at very low laboratory energies are discussed.

  8. Optic disc classification by the Heidelberg Retina Tomograph and by physicians with varying experience of glaucoma

    PubMed Central

    Andersson, S; Heijl, A; Bengtsson, B

    2011-01-01

    Purpose To compare the diagnostic accuracy of the Heidelberg Retina Tomograph's (HRT) Moorfields regression analysis (MRA) and glaucoma probability score (GPS) with that of subjective grading of optic disc photographs performed by ophthalmologists with varying experience of glaucoma and by ophthalmology residents. Methods Digitized disc photographs and HRT images from 97 glaucoma patients with visual field defects and 138 healthy individuals were classified as either within normal limits (WNL), borderline (BL), or outside normal limits (ONL). Sensitivity and specificity were compared for MRA, GPS, and the physicians. Analyses were also made according to disc size and for advanced visual field loss. Results Forty-five physicians participated. When BL results were regarded as normal, sensitivity was significantly higher (P<5%) for both MRA and GPS compared with the average physician, 87%, 79%, and 62%, respectively. Specificity ranged from 86% for MRA to 97% for general ophthalmologists, but the differences were not significant. In eyes with small discs, sensitivity was 75% for MRA, 60% for the average doctor, and 25% for GPS; in eyes with large discs, sensitivity was 100% for both GPS and MRA, but only 68% for physicians. Conclusion Our results suggest that sensitivity of MRA is superior to that of the average physician, but not that of glaucoma experts. MRA correctly classified all eyes with advanced glaucoma and showed the best sensitivity in eyes with small optic discs. PMID:21836629

  9. Whom Do Centenarians Rely on for Support? Findings From the Second Heidelberg Centenarian Study.

    PubMed

    Boerner, Kathrin; Jopp, Daniela S; Park, Min-Kyung S; Rott, Christoph

    2016-01-01

    This paper provides a detailed picture of the sources and types of informal support available to centenarians, depending on their housing and care arrangements. Participants were 112 centenarians and 96 primary contacts of centenarians enrolled in the population-based Second Heidelberg Centenarian Study. Findings indicate that children of centenarians were their primary source of support in daily life. Those without living children had overall less help. Most frequently reported was help with administrative tasks, regardless of centenarians' residence or living arrangement. All other types of help (e.g., with activities of daily living and housework) were reported by about one-third and were mostly provided by children; centenarians without children were more likely to have friends/neighbors involved in some of these tasks. The one category reported by a third of the centenarians regardless of residence, living arrangements, or presence of a child was help with socializing/companionship. Findings constitute an important step toward identifying and meeting the support needs of centenarians and their families. Policy implications are discussed. PMID:26959657

  10. Colonization of internal organs by Salmonella serovars Heidelberg and Typhimurium in experimentally infected laying hens housed in enriched colony cages at different stocking densities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contaminated eggs produced by infected commercial laying flocks are often implicated as sources of human infections with Salmonella Enteritidis, but Salmonella serovars Heidelberg and Typhimurium have also been significantly associated with egg-transmitted illness. Contamination of the edible conten...

  11. Molecular characterization of Salmonella Paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are human pathogens frequently isolated from poultry. As a step towards implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance (COIPARS), this study characterized molecular patt...

  12. Development of the ageing management database of PUSPATI TRIGA reactor

    NASA Astrophysics Data System (ADS)

    Ramli, Nurhayati; Maskin, Mazleha; Tom, Phongsakorn Prak; Husain, Nurfazila; Farid, Mohd Fairus Abd; Ramli, Shaharum; Adnan, Amirul Syazwan; Abidin, Nurul Husna Zainal

    2016-01-01

    Since its first criticality in 1982, PUSPATI TRIGA Reactor (RTP) has been operated for more than 30 years. As RTP become older, ageing problems have been seen to be the prominent issues. In addressing the ageing issues, an Ageing Management (AgeM) database for managing related ageing matters was systematically developed. This paper presents the development of AgeM database taking into account all RTP major Systems, Structures and Components (SSCs) and ageing mechanism of these SSCs through the system surveillance program.

  13. TRIGA high wt -% LEU fuel development program. Final report

    SciTech Connect

    West, G.B.

    1980-07-01

    The principal purpose of this work was to investigate the characteristics of TRIGA fuel where the contained U-235 was in a relatively high weight percent (wt %) of LEU (low enriched uranium - enrichment of less than 20%) rather than a relatively low weight percent of HEU (high enriched uranium). Fuel with up to 45 wt % U was fabricated and found to be acceptable after metallurgical examinations, fission product retention tests and physical property examinations. Design and safety analysis studies also indicated acceptable prompt negative temperature coefficient and core lifetime characteristics for these fuels.

  14. The SANS facility at the Pitesti 14MW TRIGA reactor

    SciTech Connect

    Ionita, I. Grabcev, B.; Todireanu, S.; Constantin, F.; Shvetsov, V.; Anghel, E.; Popescu, G.; Mincu, M.; Datcu, A.

    2006-12-15

    The SANS facility existing at the Pitesti 14MW TRIGA reactor is presented. The main characteristics and the preliminary evaluation of the installation performances are given. A monochromatic neutron beam with 1.5 A {<=} {lambda} {<=} 5 A is produced by a mechanical velocity selector with helical slots. A fruitful partnership was established between INR Pitesti (Romania) and JINR Dubna (Russia). The first step in this cooperation consists in the manufacturing in Dubna of a battery of gas-filled positional detectors devoted to the SANS instrument.

  15. Hydrogen and Oxygen Gas Production in the UT TRIGA Reflector

    SciTech Connect

    D. S. O'Kelly

    2000-11-12

    In December 1999, The University of Texas at Austin (UT) reported an unusual condition associated with the annular graphite reflector surrounding the Nuclear Engineering Teaching Laboratory (NETL) TRIGA reactor. The aluminum container encapsulating the graphite showed signs of bulging or swelling. Further, during an investigation of this occurrence, bubbles were detected coming from a weld in the aluminum. The gas composition was approximately 2:1 hydrogen to oxygen. After safety review and equipment fabrication, the reflector was successfully vented and flooded. The ratio of the gases produced is unusual, and the gas production mechanism has not yet been explained.

  16. Differential ex vivo responses of primary leukocytes from turkey pedigree lines to Salmonella Heidelberg.

    PubMed

    Potter, Tiffany D; Glover, Paige K; Evans, Nicholas P; Dalloul, Rami A

    2016-02-01

    Escalating product recalls as a consequence of Salmonella-contaminated poultry products have resulted in detrimental economic impacts in the poultry industry. One potential long-term alternative method to Salmonella prevention is genetic selection to improve innate resistance. This study evaluated the ex vivo effects of Salmonella Heidelberg (SH) on phagocytic and bactericidal leukocyte function in turkeys from six pedigree lines (A-F). Day-of-hatch poults (n = 48) were placed and raised in cages (2 birds/gender/genetic line/cage) to 35 d when heterophils and peripheral blood mononuclear cells (PBMCs) were extracted from males and females of each line. Cells were used in phagocytic and bactericidal assays to determine the ex vivo effects of SH on turkey leukocyte activity. Data were analyzed using the Fit Model platform in JMP Pro 10.0 (SAS Institute Inc.) with differences considered significant at P ≤ 0.05 and data reported as LS Means with SEM. Although genetic line had no significant effect on phagocytosis of SH by heterophils and PBMCs, cumulatively, female cells exhibited higher phagocytosis potential than those from males. The main effect of gender was significant on bactericidal activity of PBMCs when incubated at a 1:10 and 1:100 PBMC to SH ratio. Genetic line also had a significant effect on bactericidal activity of PBMCs with cells from line F exhibiting the best activity. These results suggest that gender had a marked cumulative effect on phagocytosis of SH by heterophils and PBMCs while both genetic line and gender had a prominent effect on bacterial killing of SH by turkey PBMCs. Once able to determine genetic markers associated with these immune responses to Salmonella, genetic selection for increased resistance may become feasible in turkeys. PMID:26706359

  17. Transport of fission products with a helium gas-jet at TRIGA-SPEC

    NASA Astrophysics Data System (ADS)

    Eibach, M.; Beyer, T.; Blaum, K.; Block, M.; Eberhardt, K.; Herfurth, F.; Geppert, C.; Ketelaer, J.; Ketter, J.; Krämer, J.; Krieger, A.; Knuth, K.; Nagy, Sz.; Nörtershäuser, W.; Smorra, C.

    2010-02-01

    A helium gas-jet system for the transport of fission products from the research reactor TRIGA Mainz has been developed, characterized and tested within the TRIGA-SPEC experiment. For the first time at TRIGA Mainz carbon aerosol particles have been used for the transport of radionuclides from a target chamber with high efficiency. The radionuclides have been identified by means of γ-spectroscopy. Transport time, efficiency as well as the absolute number of transported radionuclides for several species have been determined. The design and the characterization of the gas-jet system are described and discussed.

  18. Analysis of cocked fuel elements in the AFRRI TRIGA Mark-F reactor

    SciTech Connect

    Sholtis, Joseph A. Jr.

    1982-07-01

    The Armed Forces Radiobiology Research Institute (AFRRI) TRIGA Mark-F pulsing reactor has experienced eight cocked fuel elements during the period 5 November 1974 through 17 February 1982. Although there are no adverse health and safety consequences associated with their occurrence and there is no credible potential for system damage, cocked TRIGA fuel elements do cause inconvenience to the reactor staff and a temporary delay in operations. This paper presents the history of cocked TRIGA fuel elements at AFRRI, discusses possible mechanisms for their occurrence, and outlines a plan to isolate and ultimately determine their actual cause.

  19. Modification of the Core Cooling System of TRIGA 2000 Reactor

    SciTech Connect

    Umar, Efrizon; Fiantini, Rosalina

    2010-06-22

    To accomplish safety requirements, a set of actions has to be performed following the recommendations of the IAEA safety series 35 applied to research reactor. Such actions are considered in modernization of the old system, improving the core cooling system and safety evaluations. Due to the complexity of the process and the difficulty in putting the apparatus in the reactor core, analytical and experimental study on the determination of flow and temperature distribution in the whole coolant channel are difficult to be done. In the present work, a numerical study of flow and temperature distribution in the coolant channel of TRIGA 2000 has been carried out using CFD package. For this study, simulations were carried out on 3-D tested model. The model consists of the reactor tank, thermal and thermalizing column, reflector, rotary specimen rack, chimney, fuel element, primary pipe, diffuser, beam tube and a part of the core are constructed by 1.50 million unstructured tetrahedral cell elements. The results show that for the initial condition (116 fuel elements in the core) and for the inlet temperature of 24 deg. C and the primary velocity of 5.6 m/s, there no boiling phenomena occur in the coolant channel. Due to this result, it is now possible to improve the core cooling system of TRIGA 2000 reactor. Meanwhile, forced flow from the diffuser system only affected the flow pattern in the outside of chimney and put on a small effect to the fluid flow's velocity in the inside of chimney.

  20. Modification of the Core Cooling System of TRIGA 2000 Reactor

    NASA Astrophysics Data System (ADS)

    Umar, Efrizon; Fiantini, Rosalina

    2010-06-01

    To accomplish safety requirements, a set of actions has to be performed following the recommendations of the IAEA safety series 35 applied to research reactor. Such actions are considered in modernization of the old system, improving the core cooling system and safety evaluations. Due to the complexity of the process and the difficulty in putting the apparatus in the reactor core, analytical and experimental study on the determination of flow and temperature distribution in the whole coolant channel are difficult to be done. In the present work, a numerical study of flow and temperature distribution in the coolant channel of TRIGA 2000 has been carried out using CFD package. For this study, simulations were carried out on 3-D tested model. The model consists of the reactor tank, thermal and thermalizing column, reflector, rotary specimen rack, chimney, fuel element, primary pipe, diffuser, beam tube and a part of the core are constructed by 1.50 million unstructured tetrahedral cell elements. The results show that for the initial condition (116 fuel elements in the core) and for the inlet temperature of 24°C and the primary velocity of 5.6 m/s, there no boiling phenomena occur in the coolant channel. Due to this result, it is now possible to improve the core cooling system of TRIGA 2000 reactor. Meanwhile, forced flow from the diffuser system only affected the flow pattern in the outside of chimney and put on a small effect to the fluid flow's velocity in the inside of chimney.

  1. Design Verification Report Neutron Radiography Facility (NRF) TRIGA Fuel Storage Systems

    SciTech Connect

    CARRELL, R.D.

    2002-01-31

    This report outlines the methods, procedures, and outputs developed during the Neutron Radiography Facility (NRF) Training, Research and Isotope Production, General Atomics (TRIGA) fuel storage system design and fabrication.

  2. [Quality assurance in heart surgery: 8 years experience with a "feedback-control" system in Heidelberg].

    PubMed

    Vahl, C F; Meinzer, P; Thomas, G; Osswald, B R; Hagl, S

    1996-12-01

    An important aspect of quality assurance in cardiac surgery covers the epidemiological analysis of patient data. After an 8 year period of clinical experience with quality assurance, we summarize and evaluate current concepts and actual experiences regarding a special type of database application and organisation ("feedback-control-system") for quality assurance. It had been developed to meet and solve the problems related to the data acquisition process, that are typically present in the clinical routine of quality assurance. In 1988 the "feedback-control-system" was designed and implemented in the Department of Cardiac Surgery at Heidelberg University. Since then it had been continuously improved and adapted to satisfy current needs in cardiac surgery. More than 1500 items are now recorded routinely per patient. At present, detailed information of more than 10,000 patients is available for the specific methods of analysis in the field of quality assurance. The basic concept included 1. the integration of the data acquisition in the daily clinical routine, 2. the evaluation and improvement of collected data material by means of "output-functions", that require previously recorded reliable data (that is automatically computer generated operation reports, letters, statistics, accounting etc.), and 3. to ensure that the medical and non-medical staff members participate in the advantages and the responsibilities of the data-base system for quality assurance. Analyses of perioperative risks and results, early discovery of trends, identification of special subpopulations receiving special types of treatment in cardiac surgery etc. have now become a regularly performed tool in clinical routine. This includes the availability of "problem profiles", "trend analysis", the use of simple concluding statistics as well as the calculation of multivariable models. This internal quality assurance is completed by "multicentric" comparisons with further hospitals already using the

  3. Heidelberg-Moscow {beta}{beta} experiment with {sup 76}Ge: Full setup with five detectors

    SciTech Connect

    Guenther, M.; Hellmig, J.; Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V.; Maier, B.; Paes, H.; Petry, F.; Ramachers, Y.; Strecker, H.; Voellinger, M.; Balysh, A.; Belyaev, S.T.; Demehin, A.; Gurov, A.; Kondratenko, I.; Kotelnikov, D.; Lebedev, V.I.; Mueller, A.

    1997-01-01

    The full setup of the Heidelberg-Moscow double {beta} decay experiment is presented. This experiment gives at present the most stringent upper bound, improving the neutrino mass limit into the sub-eV range. Out of 19.2 kg of 86{percent} enriched {sup 76}Ge five crystals were grown with a total mass of 11.51 kg. Since February 1995 all five detectors, corresponding to 10.96 kg active mass, are in regular operation in the Gran Sasso underground laboratory, four of them in a common shield. No signal is observed for the neutrinoless double {beta} decay (0{nu}{beta}{beta}). The measured data from the first three enriched detectors with a statistical significance of 13.60 kgyr result in a new half-life limit of T{sub 1/2}(0{sup +}{r_arrow}0{sup +}){gt}7.4{times}10{sup 24} yr (90{percent} C.L.). With this limit a Majorana mass of the neutrinos larger than 0.6 eV (90{percent} C.L.) is excluded. From the data taken in the previously operated setup with three enriched detectors in a common shielding and a statistical significance of 10.58 kgyr new results are extracted for the two neutrino double {beta} decay (2{nu}{beta}{beta}) of {sup 76}Ge. The procedure of a quantitative and model-independent description of the background via a Monte Carlo simulation is outlined in some detail. The combined result is T{sub 1/2}{sup 2{nu}}=[1.77{sub {minus}0.01}{sup +0.01}(stat){sub {minus}0.11}{sup +0.13}(sys)]{times}10{sup 21} yr. Further on the results concerning new Majoron models and the impact on SUSY parameters are briefly reviewed. Future improvements on the background with the application of digital pulse shape analysis are discussed and an outlook on the future of {beta}{beta} research is given. {copyright} {ital 1996} {ital The American Physical Society}

  4. Risks Involved in the Use of Enrofloxacin for Salmonella Enteritidis or Salmonella Heidelberg in Commercial Poultry

    PubMed Central

    Morales-Barrera, Eduardo; Calhoun, Nicole; Lobato-Tapia, Jose L.; Lucca, Vivian; Prado-Rebolledo, Omar; Hernandez-Velasco, Xochitl; Merino-Guzman, Ruben; Petrone-García, Victor M.; Latorre, Juan D.; Mahaffey, Brittany D.; Teague, Kyle D.; Graham, Lucas E.; Wolfenden, Amanda D.; Baxter, Mikayla F. A.; Hargis, Billy M.; Tellez, Guillermo

    2016-01-01

    The objectives of the present study were to evaluate the risks involved in the use of Enrofloxacin for Salmonella Enteritidis (SE) or Salmonella Heidelberg (SH) in commercial poultry and determine the effects of a probiotic as an antibiotic alternative. Two experiments were conducted to evaluate the risks involved in the use of Enrofloxacin for SE or SH in commercial poultry. Experiment 1 consisted of two trials. In each trial, chickens were assigned to one of three groups; control + SE challenged; Enrofloxacin 25 mg/kg + SE; and Enrofloxacin 50 mg/kg + SE. Chickens received Enrofloxacin in the drinking water from days 1 to 5 of age. On day 6, all groups received fresh water without any treatment. All chickens were orally gavaged with 107 cfu/chick of SE at 7 days of age and euthanized on 8 days of age. In Experiment 2, turkey poults were assigned to one of the three groups; control + SH; probiotic + SH; and Enrofloxacin 50 mg/kg + SH. Poults received probiotic or Enrofloxacin in the drinking water from days 1 to 5 of age. On day 6, poults received fresh water without any treatment. Poults were orally gavaged with 107 cfu/poult of SH at 7 days of age. Poults were weighed and humanely killed 24 h post-SH challenge to evaluate serum concentration of fluorescein isothiocyanate-dextran to evaluate intestinal permeability, metagenomics, and SH infection. In both trials of Experiment 1, chickens treated with Enrofloxacin were more susceptible to SE organ invasion and intestinal colonization when compared with control non-treated chickens (P < 0.05). In Experiment 2, poults treated with 50 mg/kg of Enrofloxacin showed an increase in body weight, however, this group also showed an increase in SH susceptibility, intestinal permeability, and lower proportion of Firmicutes and Bacteroidetes, but with control group had the highest proportion of Proteobacteria. By contrast, poults that received the probiotic had the highest

  5. TRIGA-SPEC: the prototype of MATS and LaSpec

    NASA Astrophysics Data System (ADS)

    Kaufmann, S.; Beyer, T.; Blaum, K.; Block, M.; Düllmann, Ch E.; Eberhardt, K.; Eibach, M.; Geppert, C.; Gorges, C.; Grund, J.; Hammen, M.; Krämer, J.; Nagy, Sz; Nörtershäuser, W.; Renisch, D.; Schneider, F.; Wendt, K.

    2015-04-01

    Investigation of short-lived nuclei is a challenging task that MATS and LaSpec will handle at the low energy branch of Super-FRS at FAIR. The groundwork for those experiments is laid-out already today at the TRIGA-SPEC facility as a powerful development platform located at the research reactor TRIGA Mainz. The latest status, new developments and first results of commissioning runs are presented here.

  6. A combined wet/dry sipping cell for investigating failed TRIGA fuel elements

    SciTech Connect

    Hammer, J.; Gallhammer, H.; Bock, H.

    1988-07-01

    Investigation for a failed TRIGA fuel element is performed with the help of a combined wet/dry sipping cell, which has been designed and fabricated at the Atominstitut Vienna. In this sipping cell a TRIGA fuel element can be studied for fission product release, both at normal and at elevated temperatures. This report describes the design features of the sipping cell and the fission product identification procedure with the help of a high purity Germanium detector and a multichannel analyzer.

  7. Code System to Calculate Mixed Cores in TRIGA Mark II Research Reactor.

    Energy Science and Technology Software Center (ESTSC)

    2001-08-29

    Version 00 TRIGLAV is a computer program for reactor calculations of mixed cores in a TRIGA Mark II research reactor. It can be applied for fuel element burn-up calculations, for power and flux distributions calculations and for reactivity predictions. The TRIGLAV program requires the WIMS-D4 program with the original WIMS cross-section library extended for TRIGA reactor specific nuclides. This package includes the code TRIGAC, which is a new version of TRIGAP.

  8. Environmental Assessment: Relocation and storage of TRIGA{reg_sign} reactor fuel, Hanford Site, Richland, Washington

    SciTech Connect

    1995-08-01

    In order to allow the shutdown of the Hanford 308 Building in the 300 Area, it is proposed to relocate fuel assemblies (101 irradiated, three unirradiated) from the Mark I TRIGA Reactor storage pool. The irradiated fuel assemblies would be stored in casks in the Interim Storage Area in the Hanford 400 Area; the three unirradiated ones would be transferred to another TRIGA reactor. The relocation is not expected to change the offsite exposure from all Hanford Site 300 and 400 Area operations.

  9. Assessment results of the Indonesian TRIGA SNF to be shipped to INEEL

    SciTech Connect

    Jefimoff, J.; Robb, A.K.; Wendt, K.M.; Syarip, I.; Alfa, T.

    1997-10-09

    This paper describes the Training, Research, Isotope, General Atomics (TRIGA) spent nuclear fuel (SNF) examination performed by technical personnel from the Idaho National Engineering and Environmental Laboratory (INEEL) at the Bandung and Yogyakarta research reactor facilities in Indonesia. The examination was required before the SNF would be accepted for transportation to and storage at the INEEL. This paper delineates the Initial Preparations prior to the Indonesian foreign research reactor (FRR) fuel examination. The technical basis for the examination, the TRIGA SNF Acceptance Criteria, and the physical condition required for transportation, receipt and storage of the TRIGA SNF at the INEEL is explained. In addition to the initial preparations, preparation descriptions of the Work Plan For TRIGA Fuel Examination, the Underwater Examination Equipment used, and personnel Examination Team Training are included. Finally, the Fuel Examination and Results of the aluminum and stainless steel clad TRIGA fuel examination have been summarized. Lessons learned from all the activities completed to date is provided in an addendum. The initial preparations included: (1) coordination between the INEEL, FRR or Badan Tenaga Atom Nasional (BATAN), DOE-HQ, and the US State Department and Embassy; (2) incorporating Savannah River Site (SRS) FRR experience and lessons learned; (3) collecting both FRR facility and spent fuel data, and issuing a radionuclide report (Radionuclide Mass Inventory, Activity, Decay Heat, and Dose Rate Parametric Data for TRIGA Spent Nuclear Fuels) needed for transportation and fuel acceptance at the INEEL; and (4) preexamination work at the research reactor for the fuel examination.

  10. The characterization of Salmonella enterica serotypes isolated from the scalder tank water of a commercial poultry processing plant: Recovery of a multidrug-resistant Heidelberg strain.

    PubMed

    Rothrock, Michael J; Ingram, Kimberly D; Gamble, John; Guard, Jean; Cicconi-Hogan, Kellie M; Hinton, Arthur; Hiett, Kelli L

    2015-03-01

    The recent multistate outbreak of a multidrug-resistant (MDR) Salmonella Heidelberg strain from commercial poultry production highlights the need to better understand the reservoirs of these zoonotic pathogens within the commercial poultry production and processing environment. As part of a larger study looking at temporal changes in microbial communities within the major water tanks within a commercial processing facility, this paper identifies and characterizes Salmonella enterica isolated from the water in a final scalder tank at 3 times during a typical processing day: prior to the birds entering the tank (start), halfway through the processing day (mid), and after the final birds were scalded (end). Over 3 consecutive processing days, no Salmonella were recovered from start-of-day water samples, while a total of 56 Salmonella isolates were recovered from the mid-day and end-of-day scalder water samples. Traditional and newer PCR-based serotyping methods eventually identified these isolates as either group C3 S. Kentucky (n=45) and group B S. Heidelberg (n=11). While none of the S. Kentucky isolates possessed any resistances to the antimicrobials tested, all S. Heidelberg isolates were found to be multidrug resistant to 5 specific antimicrobials representing 3 antimicrobial classes. Due to the potential public health impact of S. Heidelberg and the recent nationwide poultry-associated outbreak of multidrug-resistant S. Heidelberg, future studies should focus on understanding the transmission and environmental growth dynamics of this serotype within the commercial poultry processing plant environment. PMID:25681479

  11. New fuel management plan for the Penn State TRIGA

    SciTech Connect

    Hughes, D.; Boyle, P.; Levine, S.H.

    1996-12-31

    The Pennsylvania State University (PSU) Breazeale TRIGA has utilized 12 wt% U fuel in the core since July 1992, when six 12 wt% U fuel elements were loaded to replace the depleted 8.5 wt% U fuel in the centermost ring, the B ring. This reload increased the cold k{sub eff} from 1.03 to 1.05, the cold k{sub eff} of 1.03 being the minimum k{sub eff} that will permit 1-MW operation for a sustained period. In the next fuel reload, this 12 wt% U fuel is to be moved outward to the adjacent ring, the C ring, and six fresh 12 wt% U fuel elements are to be added to the B ring. It was determined that using the 12 wt% U in place of 8.5 wt% U fuel reduced fuel costs by a factor of 6, and continuing this use of six 12 wt% U fuel elements for each reload maintained the lower fuel costs. This reloading technique worked successfully, requiring only 26 additional 12 wt% U elements to be loaded into the core during the last 23 yr. Recently, however, a new instrumented 12 wt% U fuel element read much higher temperatures than all previous similar fuel elements. Its measured fuel temperature at 1 MW is 585{degrees}C. As a result, the PSU TRIGA now operates at or below 60% full power to prevent this element from reaching fuel temperatures well above 500{degrees}C. The purpose of this paper is to describe a new fuel management strategy developed to use 12 wt% U fuel, which permits 1-MW operation and limits the maximum fuel temperature to {approx}500{degrees}C.

  12. Reactor instrumentation renewal of the TRIGA reactor Vienna, Austria

    SciTech Connect

    Boeck, H.; Weiss, H.; Hood, W.E.; Hyde, W.K.

    1992-07-01

    The TRIGA Mark-II reactor at the Atominstitut in Vienna, Austria is replacing its twenty-four year old instrumentation system with a microprocessor based control system supplied by General Atomics. Ageing components, new governmental safety requirements and a need for state of the art instrumentation for training students has spurred the demand for new reactor instrumentation. In Austria a government appointed expert is assigned the responsibility of reviewing the proposed installation and verifying all safety aspects. After a positive review, final assembly and checkout of the instrumentation system may commence. The instrumentation system consists of three basic modules: the control system console, the data acquisition console and the NH-1000 wide range channel. Digital communications greatly reduce interwiring requirements. Hardwired safety channels are independent of computer control, thus, the instrumentation system in no way relies on any computer intervention for safety function. In addition, both the CSC and DAC computers are continuously monitored for proper operation via watchdog circuits which are capable of shutting down the reactor in the event of computer malfunction. Safety channels include two interlocked NMP-1000 multi-range linear channels for steady state mode, an NPP-1000 linear safety channel for pulse mode and a set of three independent fuel temperature monitoring channels. The microprocessor controlled wide range NM- 1000 digital neutron monitor (fission chamber based) functions as a startup/operational channel, and provides all power level related Interlocks. The Atominstitut TRIGA reactor is configured for four modes of operation: manual mode, automatic mode (servo control), pulsing mode and square wave mode. Control of the standard control rods is via stepping motor control rod drives, which offers the operator the choice of which control rods are operated by the servo system in automatic and square wave model. (author)

  13. Tri-Gas Pressurization System Testing and Modeling for Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Taylor, B.; Polsgrove, R.; Stephens, J.; Hedayat, A.

    2014-01-01

    The use of Tri-gas in rocket propulsion systems is somewhat of a new technology. This paper defines Tri-gas as a mixture of gases composed largely of helium with a small percentage of a stoichiometric mixture of hydrogen and oxygen. When exposed to a catalyst the hydrogen and oxygen in the mixture combusts, significantly raising the temperature of the mixture. The increase in enthalpy resulting from the combustion process significantly decreases the required quantity of gas needed to pressurize the ullage of the vehicle propellant tanks. The objective of this effort was to better understand the operating characteristics of Tri-gas in a pressurization system with low temperature applications. In conjunction with ongoing programs at NASA Marshall Space Flight Center, an effort has been undertaken to evaluate the operating characteristics of Tri-gas through modeling and bench testing. Through improved understanding of the operating characteristics, the risk of using this new technology in a launch vehicle propulsion system was reduced. Bench testing of Tri-gas was a multistep process that targeted gas characteristics and performance aspects that pose a risk to application in a pressurization system. Pressurization systems are vital to propulsion system performance. Keeping a target ullage pressure in propulsions tanks is necessary to supply propellant at the conditions and flow rates required to maintain desired engine functionality. The first component of testing consisted of sampling Tri-gas sources that had been stagnant for various lengths of time in order to determine the rate at which stratification takes place. Second, a bench test was set up in which Tri-gas was sent through a catalyst bed. This test was designed to evaluate the performance characteristics of Tri-gas, under low temperature inlet temperatures, in a flight-like catalyst bed reactor. The third, most complex, test examined the performance characteristics of Tri-gas at low temperature temperatures

  14. 78 FR 5840 - Notice of License Termination for University of Illinois Advanced TRIGA Reactor, License No. R-115

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ... COMMISSION Notice of License Termination for University of Illinois Advanced TRIGA Reactor, License No. R-115... No. R-115, for the University of Illinois Advanced TRIGA Reactor (ATR). The NRC has terminated the..., Facility Operating License No. R-115 is terminated. The above referenced documents may be examined,...

  15. An analysis of decommissioning costs for the AFRRI TRIGA reactor facility

    SciTech Connect

    Forsbacka, Matt

    1990-07-01

    A decommissioning cost analysis for the AFRRI TRIGA Reactor Facility was made. AFRRI is not at this time suggesting that the AFRRI TRIGA Reactor Facility be decommissioned. This report was prepared to be in compliance with paragraph 50.33 of Title 10, Code of Federal Regulations which requires the assurance of availability of future decommissioning funding. The planned method of decommissioning is the immediate decontamination of the AFRRI TRIGA Reactor site to allow for restoration of the site to full public access - this is called DECON. The cost of DECON for the AFRRI TRIGA Reactor Facility in 1990 dollars is estimated to be $3,200,000. The anticipated ancillary costs of facility site demobilization and spent fuel shipment is an additional $600,000. Thus the total cost of terminating reactor operations at AFRRI will be about $3,800,000. The primary basis for this cost estimate is a study of the decommissioning costs of a similar reactor facility that was performed by Battelle Pacific Northwest Laboratory (PNL) as provided in USNRC publication NUREG/CR-1756. The data in this study were adapted to reflect the decommissioning requirements of the AFRRI TRIGA. (author)

  16. Neutron and gamma radiography of UO{sub 2} and TRIGA fuel elements

    SciTech Connect

    Robinson, A.H.; Gao, Y.C.; Johnson, A.G.; Ringle, J.C.

    1982-07-01

    The Oregon State TRIGA Reactor neutron radiography facility has been used to produce both neutron and gamma radiographs of reactor fuel. In this paper a comparison of the applicability of neutron and gamma radiography to both UO{sub 2} fuel pins and TRIGA fuel elements is made. In the case of UO{sub 2} fuel, conventional thermal neutron radiography produces excellent quality radiographs. These radiographs may be used to detect various defects in the fuel such as enrichment differences, cracks, end-capping, inclusions, etc. For TRIGA fuel elements, conventional thermal neutron radiography will not show the internal structure. This is due to the high hydrogen content of the fuel. These elements are typically 8.5 w/o uranium in Zr-H{sub 1.7}; the density of hydrogen in the fuel being about 80 percent that of water. Further, while epithermal radiography significantly improves the radiographs, defects may go undetected. As an alternative to neutron radiography, high energy gamma radiographs of TRIGA fuel elements have been taken using the same facility. The gamma spectrum emitted by the reactor core is sufficiently high in energy that very good radiographs may be obtained with this technique. These radiographs show excellent detail for the internal structure of the TRIGA fuel. (author)

  17. Thermal hydraulics modeling of the US Geological Survey TRIGA reactor

    NASA Astrophysics Data System (ADS)

    Alkaabi, Ahmed K.

    The Geological Survey TRIGA reactor (GSTR) is a 1 MW Mark I TRIGA reactor located in Lakewood, Colorado. Single channel GSTR thermal hydraulics models built using RELAP5/MOD3.3, RELAP5-3D, TRACE, and COMSOL Multiphysics predict the fuel, outer clad, and coolant temperatures as a function of position in the core. The results from the RELAP5/MOD3.3, RELAP5-3D, and COMSOL models are similar. The TRACE model predicts significantly higher temperatures, potentially resulting from inappropriate convection correlations. To more accurately study the complex fluid flow patterns within the core, this research develops detailed RELAP5/MOD3.3 and COMSOL multichannel models of the GSTR core. The multichannel models predict lower fuel, outer clad, and coolant temperatures compared to the single channel models by up to 16.7°C, 4.8°C, and 9.6°C, respectively, as a result of the higher mass flow rates predicted by these models. The single channel models and the RELAP5/MOD3.3 multichannel model predict that the coolant temperatures in all fuel rings rise axially with core height, as the coolant in these models flows predominantly in the axial direction. The coolant temperatures predicted by the COMSOL multichannel model rise with core height in the B-, C-, and D-rings and peak and then decrease in the E-, F-, and G-rings, as the coolant tends to flow from the bottom sides of the core to the center of the core in this model. Experiments at the GSTR measured coolant temperatures in the GSTR core to validate the developed models. The axial temperature profiles measured in the GSTR show that the flow patterns predicted by the COMSOL multichannel model are consistent with the actual conditions in the core. Adjusting the RELAP5/MOD3.3 single and multichannel models by modifying the axial and cross-flow areas allow them to better predict the GSTR coolant temperatures; however, the adjusted models still fail to predict accurate axial temperature profiles in the E-, F-, and G-rings.

  18. Long-term effects of the “Heidelberg Model of Music Therapy” in patients with chronic tinnitus

    PubMed Central

    Argstatter, Heike; Grapp, Miriam; Hutter, Elisabeth; Plinkert, Peter; Bolay, Hans Volker

    2012-01-01

    Objective The “Heidelberg Model of Music Therapy for Chronic Tinnitus” is a manualized short term treatment (nine 50-minutes sessions of individualized therapy on five consecutive days). It has proven to be efficient in reducing tinnitus symptoms in the short run. Now the long-term impact of the treatment after up to 5.4 years should be explored. Materials and methods 206 patients who had attended the neuro-music therapy were addressed in a structured follow-up questionnaire survey. 107 complete questionnaires entered analysis. Follow-up time was 2.65 (SD 1.1) years. Results 76% of the patients achieved a reliable reduction in their tinnitus scores, the overall tinnitus distress as measured by the Mini-TQ diminished from 11.9 (SD = 4.9) to 7.4 (SD = 5.2) points, 87% of the patients were satisfied by the way they were treated during therapy, and 71% of the patients did not undergo any further treatment after. Evaluation of therapeutic elements displays, that only music therapy specific interventions were rated helpful by the patients. Tinnitus related factors (such as tinnitus pitch or loudness, time since onset) did not influence therapy outcome but female gender, positive therapeutic relationship, and higher initial Mini-TQ scores became apparent as factors predicting better chances for greater therapy success. Discussion The “Heidelberg Model of Music Therapy for Chronic Tinnitus” seems to be effective in the long run. The outcome effect size of d’ = 0.89, can be accounted for as “large” effect and falls into the upper range value compared to established treatments. PMID:22993646

  19. Retinal Thickness in People with Diabetes and Minimal or No Diabetic Retinopathy: Heidelberg Spectralis Optical Coherence Tomography

    PubMed Central

    Chalam, Kakarla V.; Bressler, Susan B.; Edwards, Allison R.; Berger, Brian B.; Bressler, Neil M.; Glassman, Adam R.; Grover, Sandeep; Gupta, Shailesh K.; Nielsen, Jared S.

    2012-01-01

    Purpose. To evaluate macular thickness in people with diabetes but minimal or no retinopathy using Heidelberg Spectralis optical coherence tomography (OCT). Methods. In a multicenter, cross-sectional study of mean retinal thickness, on Spectralis OCT in the nine standard OCT subfields, spanning a zone with 6-mm diameter, center point, and total retinal volume were evaluated. Central subfield (CSF) thickness was evaluated for association with demographic and clinical factors. Stratus OCT scans also were performed on each participant. Results. The analysis included 122 eyes (122 participants) with diabetes and no (n = 103) or minimal diabetic retinopathy (n = 19) and no macular retinal thickening on clinical exam. Average CSF thickness was 270 ± 24 μm. Central subfield thickness was significantly greater in males relative to females (mean 278 ± 23 μm vs. 262 ± 22 μm, P < 0.001). After adjusting for gender, no additional factors were found to be significantly associated with CSF thickness (P > 0.10). Mean Stratus OCT CSF thickness was 199 ± 24 μm. Conclusions. Mean CSF thickness is approximately 70 μm thicker when measured with Heidelberg Spectralis OCT as compared with Stratus OCT among individuals with diabetes in the absence of retinopathy or with minimal nonproliferative retinopathy and a normal macular architecture. CSF thickness values ≥320 μm for males and 305 μm for females (∼2 SDs above the average for this normative cohort) are proposed as gender-specific thickness levels to have reasonable certainty that diabetic macular edema involving the CSF is present using Spectralis measurements. PMID:23132803

  20. Colonization of internal organs by Salmonella serovars Heidelberg and Typhimurium in experimentally infected laying hens housed in enriched colony cages at different stocking densities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contaminated eggs produced by infected commercial laying flocks are often implicated as sources of human infections with Salmonella Enteritidis, but Salmonella serovars Heidelberg and Typhimurium have also been associated with egg-transmitted illness. Contamination of the edible contents of eggs is ...

  1. Molecular characterization of Salmonella paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis.

    PubMed

    Donado-Godoy, Pilar; Byrne, Barbara A; Hume, Michael; León, Maribel; Pérez-Gutiérrez, Enriqué; Vives Flores, Martha J; Clavijo, Viviana; Holguin, Ángela; Romero-Zuñiga, Juan J; Castellanos, Ricardo; Tafur, McAllister; Smith, Woutrina A

    2015-04-01

    Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are pathogens of public health importance that are frequently isolated from poultry. As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance, this study characterized molecular patterns of Salmonella Paratyphi B dT+ and Salmonella Heidelberg isolated from poultry farms, fecal samples, and retail chicken meat using pulsed-field gel electrophoresis (PFGE). The objective of this study was to determine the genetic relationship among isolates and to determine potential geographically predominant genotypes. Based on PFGE analysis, both serovars exhibited high heterogeneity: the chromosomal DNA fingerprints of 82 Salmonella Paratyphi B dT+ isolates revealed 42 PFGE patterns, whereas the 21 isolates of Salmonella Heidelberg revealed 10 patterns. Similar genotypes of both serovars were demonstrated to be present on farms and in retail outlets. For Salmonella Paratyphi B dT+, closely genetically related strains were found among isolates coming from different farms and different integrated poultry companies within two departments (Santander and Cundinamarca) and also from farms located in the two geographically distant departments. For Salmonella Heidelberg, there were fewer farms with genetically related isolates than for Salmonella Paratyphi B dT+. A possible dissemination of similar genotypes of both serovars along the poultry production chain is hypothesized, and some facilitating factors existing in Colombia are reviewed. PMID:25836408

  2. Characterization of multidrug-resistant Salmonella enterica serovar Heidelberg from a ground turkey-associated outbreak in the United States in 2011

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In March 2011, a multi-state outbreak of Salmonella enterica ser. Heidelberg infections was investigated. Pulsed-field gel electrophoresis (PFGE) analysis of isolates from suspected cases and an epidemiologic investigation identified 136 case patients from 34 states from February to September. Two...

  3. Interpretation of TRIGA reactivity transients with RELAP5/PARCS coupled-code

    SciTech Connect

    Bandini, G.; Meloni, P.; Polidori, M.

    2006-07-01

    In the frame of future experiments to carried out upon TRIGA reactors, which aim to verify the real feasibility of the ADS (Accelerator Driven System) concept, it is essential to build a numerical tool able to simulate the dynamic behaviour of the reactor in subcritical configuration. This model developed to support the design of subcritical experiments and the safety analysis of the reactor, as a first step has to be assessed against the experimental data available for the critical reactor. To this purpose the thermal-hydraulic/ neutronic numerical model based on the RELAP5/PARCS coupled-code is been tested against the experimental reactivity transients conducted on the RC1-TRIGA reactor at the ENEA Casaccia Research Center in forecast of the TRADE (TRIGA Accelerator Driven Experiment) subcritical experience. The results of the calculations already performed show a qualitative good agreement with the experimental data and allow to address the future developments and improvements of the numerical model. (authors)

  4. TRIGA Mark II Criticality Benchmark Experiment with Burned Fuel

    SciTech Connect

    Persic, Andreja; Ravnik, Matjaz; Zagar, Tomaz

    2000-12-15

    The experimental results of criticality benchmark experiments performed at the Jozef Stefan Institute TRIGA Mark II reactor are presented. The experiments were performed with partly burned fuel in two compact and uniform core configurations in the same arrangements as were used in the fresh fuel criticality benchmark experiment performed in 1991. In the experiments, both core configurations contained only 12 wt% U-ZrH fuel with 20% enriched uranium. The first experimental core contained 43 fuel elements with average burnup of 1.22 MWd or 2.8% {sup 235}U burned. The last experimental core configuration was composed of 48 fuel elements with average burnup of 1.15 MWd or 2.6% {sup 235}U burned. The experimental determination of k{sub eff} for both core configurations, one subcritical and one critical, are presented. Burnup for all fuel elements was calculated in two-dimensional four-group diffusion approximation using the TRIGLAV code. The burnup of several fuel elements was measured also by the reactivity method.

  5. Behavior of 12 wt% TRIGA fuel after many years of operation

    SciTech Connect

    Levine, S.H.; Boyle, P.

    1997-12-01

    In July 1972, six 12 wt% Uzr-H TRIGA fuel elements were loaded into the B-ring, the innermost ring, of the Penn State Breazeale Research Reactor (PSBR) to increase its k{sub eff}. Of these initial six fuel elements, three remain in the core, and the other three fuel elements had to be removed from the core. The purpose of this summary is to present operational-type data on the 12 wt% Uzr-H TRIGA fuel elements that have been in the PSBR during the past 25 yr and to postulate reasons for the structural change of those removed from the core.

  6. TRIGA Mark II benchmark experiment; Part I: Steady-state operation

    SciTech Connect

    Mele, I.; Ravnik, M.; Trkov, A. )

    1994-01-01

    The experimental results of startup tests after reconstruction and modification of the TRIGA Mark II reactor in Ljubljana are presented. The experiments were performed with a completely fresh, compact, and uniform core. The operating conditions were well defined and controlled, so that the results can be used as a benchmark test case for TRIGA reactor calculations. Both steady-state and pulse mode operation were tested. In this paper, the following steady-state experiments are treated: critical core and excess reactivity, control rod worths, fuel element reactivity worth distribution, fuel temperature distribution, and fuel temperature reactivity coefficient.

  7. Neutron fluence and energy reproducibility of a 2-dollar TRIGA reactor Pulse

    SciTech Connect

    Payne, Rosara F.; Drader, Jessica A.; Friese, Judah I.; Greenwood, Lawrence R.; Hines, Corey C.; Metz, Lori A.; Kephart, Jeremy D.; King, Matthew D.; Pierson, Bruce D.; Smith, Jeremy D.; Wall, Donald E.

    2009-10-01

    Washington State University’s 1 MW TRIGA reactor has a long history of utilization for neutron activation analysis (NAA). TRIGA reactors have the ability to pulse, reach supercritical (k>1) for short bursts of time. At this high power and fast time the energy spectrum and neutron fluence are largely uncharacterized. The pulse neutron energy spectrum and fluence were determined by the activation of Cu, Au, Co, Fe, and Ti. These analyses were completed with and without Cd shielding to determine reproducibility between pulses. The applications and implications of the neutron energy and fluence reproducibility to the use of pulsed NAA will be discussed.

  8. The U-ZrH{sub x} alloy: Its properties and use in TRIGA fuel

    SciTech Connect

    Simnad, M.T.

    1980-07-01

    The uranium-zirconium-hydride fuel is an integral fuel-moderator system. Development of the UZr-hydride fuel technology has been under way at General Atomic since 1957. During this period over 6000 fuel elements have been fabricated for the TRIGA reactors. Over 25,000 pulses have been performed with the TRIGA fuel elements at General Atomic. The TRIGA fuel was developed around the concept of inherent safety. The development and the characteristics of the TRIGA fuels are described in this paper. The fabrication techniques have been developed to the point where the production of fuel bodies containing controlled amounts of hydrogen and burnable poison (erbium) has been carried out in sizes up to 1.5 in. in diameter. The instrumented fuel elements have been designed to determine the temperatures in the fuels and claddings and to record the gas pressures in the fuel elements, under both steady- state and pulsed operations. The physical, mechanical and corrosion properties of the fuel are presented, along with empirical correlations relating irradiation behavior and fission product retention to temperature, composition, burnup, and neutron flux and fluence. (author)

  9. Analysis of decommissioning costs for the AFRRI TRIGA reactor facility. Technical report

    SciTech Connect

    Forsbacka, M.; Moore, M.

    1989-12-01

    This report provides a cost analysis for decommissioning the Armed Forces Radiobiology Research Institute (AFRRI) TRIGA reactor facility. AFRRI is not suggesting that the AFRRI TRIGA reactor facility be decommissioned. This report was prepared in compliance with paragraph 50.33 of Title 10, Code of Federal Regulations, which requires that funding for the decommissioning of reactor facilities be available when licensed activities cease. The planned method of decommissioning is complete decontamination (DECON) of the AFRRI TRIGA reactor site to allow for restoration of the site to full public access. The cost of DECON in 1990 dollars is estimated to be $3,200,000. The anticipated ancillary costs of facility site demobilization and spent fuel shipment will be an additional $600,000. Thus, the total cost of terminating reactor operations at AFRRI will be about $3,800,000. The primary basis for developing this cost estimate was a study of the decommissioning costs of similar reactor facility performed by Battelle Pacific Northwest Laboratory, as provided in U.S. Nuclear Regulatory Commission publication NUREG/CR-1756. The data in this study were adapted to reflect the decommissioning requirements of the AFRRI TRIGA reactor facility.

  10. 10. biennial U.S. TRIGA users' conference. Papers and abstracts

    SciTech Connect

    1986-07-01

    The conference cover the following main topics for TRIGA reactors: reactor instrumentation and measurements of reactor parameters, reactor operation and modifications, design innovation and service works, fast neutron spectrum, fuel examination, neutron flux, heat transfer, accidents analysis, corrosion problems, fuel failures and fuel management, mechanical problems and maintenance.

  11. A combined gamma scanning and optical inspection system for spent TRIGA fuel

    SciTech Connect

    Boeck, H.; Allmer, G.

    1990-07-01

    A multipurpose lead container is used to investigate both the burn-up and the mechanical condition of standard TRIGA fuel elements. Especially in view of ageing reactor cores, this equipment is important to determine the further use of a specific fuel element and, therefore, saves operational costs.

  12. 11. biennial U.S. TRIGA users' conference. Papers and abstracts

    SciTech Connect

    1988-07-01

    The Conference was devoted to different aspects of TRIGA reactors design, operation and applications. The main topics concerned fuel elements, control rod drive system; modelling of corrosion damage and other chemical and material studies; neutron flux measurements and spectrum; irradiation devices; fuel element failures; neutron radiography etc.

  13. An Integrated Marine Propulsion System Utilising TRIGA{sup TM} Fuel

    SciTech Connect

    Manach, G.; Monnez, J-P.; Freeman, M.J.; Newell, A.; Brushwood, J.M.; Thompson, A.; Collins, C.; Scholes, N.; Hamilton, P.J.; Beeley, P.A.

    2004-07-01

    This paper describes the reactor physics, shielding, thermal hydraulics, reactor dynamics and safety studies conducted to develop a proposed Integrated Marine Propulsion System (IMPS) utilising TRIGA{sup TM} type uranium zirconium hydride fuel. The study has demonstrated that the IMPS plant is feasible and meets the design safety principles and safety criteria imposed on the study. (authors)

  14. Cryogenic Concept for the Low-energy Electrostatic Cryogenic Storage Ring (CSR) at MPI-K in Heidelberg

    SciTech Connect

    Hahn, R. von; Andrianarijaona, V.; Crespo Lopez-Urrutia, J. R.; Fadil, H.; Grieser, M.; Mallinger, V.; Orlov, D. A.; Schroeter, C. D.; Schwalm, D.; Ullrich, J.; Weber, T.; Wolf, A.; Haberstroh, Ch.; Quack, H.; Rappaport, M.; Zajfman, D.

    2006-04-27

    At the Max-Planck-Institut fuer Kernphysik in Heidelberg a next generation electrostatic storage ring for cryogenic temperatures is under development. The main focus of this unique machine is the research on ions, molecules and clusters up to bio molecules in the energy range of 20-300 keV at low temperatures down to 2 Kelvin. The achievement of this low temperature for all material walls seen by the ions in the storage ring will allow novel experiments to be performed, such as rotational and vibrational state control of molecular ions and their interaction with ultra-low energy electrons and laser radiation. The low temperature of the storage ring not only causes a strong reduction of black body radiation incident onto the stored particles, but also acts as a large cryopump, expected to lead to a vacuum in the 10-15 mbar range. In this paper the cryogenic concept of the storage ring and the related vacuum design will be presented.

  15. In Vivo Non Linear Optical (NLO) Imaging in Live Rabbit Eyes Using the Heidelberg Two-Photon Laser Ophthalmoscope

    PubMed Central

    Hao, Ming; Flynn, Kevin; Nien-Shy, Chyong; Jester, Bryan E.; Winkler, Moritz; Brown, Donald J.; La Schiazza, Olivier; Bille, Josef; Jester, James V.

    2010-01-01

    Imaging of non-linear optical (NLO) signals generated from the eye using ultrafast pulsed lasers has been limited to the study of ex vivo tissues because of the use of conventional microscopes with slow scan speeds. The purpose of this study was to evaluate the ability of a novel, high scan rate ophthalmoscope to generate NLO signals using an attached femtosecond laser. NLO signals were generated and imaged in live, anesthetized albino rabbits using a newly designed Heidelberg Two-Photon Laser Ophthalmoscope with attached 25 mW femtosecond laser having a central wavelength of 780 nm, pulsewidth of 75 fs, and a repetition rate of 50 MHz. To assess two-photon excited fluorescent (TPEF) signal generation, cultured rabbit corneal fibroblasts (RCF) were first labeled by Blue-green fluorescent FluoSpheres (1 μm diameter) and then cells were micro-injected into the central cornea. Clumps of RCF cells could be detected by both reflectance and TPEF imaging at 6 hours after injection. By 6 days, RCF containing fluorescent microspheres confirmed by TPEF showed a more spread morphology and had migrated from the original injection site. Overall, this study demonstrates the potential of using NLO microscopy to sequentially detect TPEF signals from live, intact corneas. We conclude that further refinement of the Two-photon laser Ophthalmoscope should lead to the development of an important, new clinical instrument capable of detecting NLO signals from patient corneas. PMID:20558159

  16. Agreement in identification of glaucomatous progression between the optic disc photography and Heidelberg retina tomography in young glaucomatous patients

    PubMed Central

    Hentova-Sencanic, Paraskeva; Sencanic, Ivan; Trajković, Goran; Bozic, Marija; Bjelovic, Nevena

    2014-01-01

    AIM To evaluate concordance between the clinical assessment of glaucomatous progression of the optic disc photography and progression identified by Heidelberg Retina Tomograph (HRT) in patients with suspected primary juvenile open angle glaucoma (JOAG). METHODS Optic disc photographs and corresponding HRT II series were reviewed. Optic disc changes between first and final photographs were noted as well as progression identified by HRT topographic change analysis (TCA) and rim area regression line (RARL) Agreement between progression indentified by photography and HRT methods was assessed. Progression, determined from optic disc photographs by consensus assessment was used as the reference standard. RESULTS A total of 31 patients (59 eyes) with suspected JOAG were studied. Agreement for progression/no progression between TCA and photography was obtained in 4 progressing eyes and 38 stable eyes (71.19%, k=0.11). Agreement for progression/no progression between RARL and photography was detected in 5 progressing eyes and in 34 stable eyes (66.10%, k=0.15). The number of HRT per patient was statistically higher in the progressing group (P=0.034). CONCLUSION Agreement for detection of longitudinal changes between photography and HRT analysis was poor. One way to improve the chance of discovery of the progression could be increasing the number of HRT examinations. PMID:24967194

  17. Exploration of Halley's Comet. Based on the 20th ESLAB Symposium, held in Heidelberg, F.R. Germany, 27 - 31 October 1986.

    NASA Astrophysics Data System (ADS)

    Grewing, M.; Praderie, F.; Reinhard, R.

    This book contains all the papers that originally appeared in the Comet Halley dedicated issue to the journal Astronomy and Astrophysics, Vol. 187, No. 1/2 (1987) (see 44.003.013) and, in addition, a summary of the scientific results presented at the Heidelberg conference and give papers providing background information on the various space missions to Halley's Comet and the International Halley Watch - see abstracts 011.046, 013.115, 051.064 - 051.67.

  18. Creating student sleuths: how a team of graduate students helped solve an outbreak of Salmonella Heidelberg infections associated with kosher broiled chicken livers.

    PubMed

    Hanson, Heather; Hancock, W Thane; Harrison, Cassandra; Kornstein, Laura; Waechter, HaeNa; Reddy, Vasudha; Luker, John; Malavet, Michelle; Huth, Paula; Gieraltowski, Laura; Balter, Sharon

    2014-08-01

    Since 2009, the New York City Department of Health and Mental Hygiene (DOHMH) has received FoodCORE funding to hire graduate students to conduct in-depth food exposure interviews of salmonellosis case patients. In 2011, an increase in the number of Salmonella Heidelberg infections with pulsed-field gel electrophoresis Xba I pattern JF6X01.0022 among observant Jewish communities in New York and New Jersey was investigated. As this pattern is common nationwide, some cases identified were not associated with the outbreak. To reduce the number of background cases, DOHMH focused on the community initially identified in the outbreak and defined a case as a person infected with the outbreak strain of Salmonella Heidelberg with illness onset from 1 April to 17 November 2011 and who consumed a kosher diet, spoke Yiddish, or self-identified as Jewish. Nationally, 190 individuals were infected with the outbreak strain of Salmonella Heidelberg; 63 New York City residents met the DOHMH case definition. In October 2011, the graduate students (Team Salmonella) interviewed three case patients who reported eating broiled chicken livers. Laboratory testing of chicken liver samples revealed the outbreak strain of Salmonella Heidelberg. Although they were only partially cooked, the livers appeared fully cooked, and consumers and retail establishment food handlers did not cook them thoroughly before eating or using them in a ready-to-eat spread. This investigation highlighted the need to prevent further illnesses from partially cooked chicken products. Removing background cases helped to focus the investigation. Training graduate students to collect exposure information can be a highly effective model for conducting foodborne disease surveillance and outbreak investigations for local and state departments of public health. PMID:25198602

  19. Association of Transferable Quinolone Resistance Determinant qnrB19 with Extended-Spectrum β-Lactamases in Salmonella Give and Salmonella Heidelberg in Venezuela

    PubMed Central

    González, Fanny

    2013-01-01

    Four nontyphoidal Salmonella strains with resistance to extended-spectrum cephalosporins and nonclassical quinolone resistance phenotype were studied. Two S. Give were isolated from pediatric patients with acute gastroenteritis, and two S. Heidelberg were recovered from raw chicken meat. Phenotypic characterization included antimicrobial susceptibility testing and detection of extended-spectrum β-lactamases (ESBLs) by the double-disc synergy method. The detection of quinolone resistance-determining regions (QRDR) of gyrA, gyrB, and gyrC genes, blaESBLs genes, and plasmid-mediated quinolone resistance (PMQR) determinants was carried out by molecular methods. Plasmid analysis included Southern blot and restriction patterns. Transferability of resistance genes was examined by transformation. blaTEM-1 + blaSHV-12 genes were detected in S. Give SG9611 and blaTEM-1 + blaCTX-M-2 in the other three strains: S. Give SG9811, S. Heidelberg SH7511, and SH7911. Regardless of origin and serovars, the qnrB19 gene was detected in the 4 strains studied. All determinants of resistance were localized in plasmids and successfully transferred by transformation. This study highlights the circulation of qnrB19 associated with blaTEM-1, blaSHV-12, and blaCTX-M-2 in S. Give and S. Heidelberg in Venezuela. The recognition of factors associated with increasing resistance and the study of the molecular mechanisms involved can lead to a more focused use of antimicrobial agents. PMID:24187555

  20. Estimating the number of human cases of ceftiofur-resistant Salmonella enterica serovar Heidelberg in Québec and Ontario, Canada.

    PubMed

    Otto, Simon J G; Carson, Carolee A; Finley, Rita L; Thomas, M Kate; Reid-Smith, Richard J; McEwen, Scott A

    2014-11-01

    A stochastic model was used to estimate the number of human cases of ceftiofur-resistant Salmonella enterica serovar Heidelberg in Québec and Ontario attributable to chicken consumption and excess cases attributable to human prior antimicrobial consumption. The annual mean incidence of S. Heidelberg (Québec/Ontario) decreased from 70/62 cases per 100 000 in 2004 to 29/30 cases per 100 000 in 2007 (Québec)/2008 (Ontario), increasing to 59/45 cases per 100 000 in 2011. The annual mean incidence of ceftiofur-resistant cases from chicken decreased from 8/7 cases per 100 000 in 2004 to 1/1 cases per 100 000 in 2007 (Québec)/2008 (Ontario), increasing to 7/5 cases per 100 000 in 2011. The annual mean total number of excess ceftiofur-resistant cases from chicken attributable to human prior antimicrobial consumption (Québec/Ontario) decreased from 71/123 in 2004 to 6/24 in 2007 (Québec)/2008 (Ontario), but increased to 62/91 in 2011. This model will support future work to determine the increased severity, mortality and healthcare costs for ceftiofur-resistant Salmonella Heidelberg infections. These results provide a basis for the evaluation of future public health interventions to address antimicrobial resistance. PMID:24982036

  1. Association Between Alzheimer's Disease and Glaucoma: A Study Based on Heidelberg Retinal Tomography and Frequency Doubling Technology Perimetry

    PubMed Central

    Cesareo, Massimo; Martucci, Alessio; Ciuffoletti, Elena; Mancino, Raffaele; Cerulli, Angelica; Sorge, Roberto P.; Martorana, Alessandro; Sancesario, Giuseppe; Nucci, Carlo

    2015-01-01

    Aim: To assess the frequency of glaucoma-like alterations in Alzheimer's disease (AD) patients using Heidelberg Retinal Tomograph III (HRT-3) and Frequency Doubling Technology (FDT) perimetry. Methods: The study included 51 eyes of 51 AD subjects and 67 eyes of 67 age- and sex-matched controls. Subjects underwent an ophthalmological examination including measurements of intraocular pressure (IOP), Matrix FDT visual field testing, optic nerve head morphology and retinal nerve fiber layer thickness (RNFLt) assessment by slit-lamp biomicroscopy and HRT-3. Results: The frequency of alterations was significantly higher in the AD group (27.5 vs. 7.5%; p = 0.003; OR = 4.69). AD patients showed lower IOP (p = 0.000) despite not significantly different values of central corneal thickness (CCT) between the groups (p = 0.336). Of all the stereometric parameters measured by HRT-3, RNFLt was significantly lower in AD patients (p = 0.013). This group also had significantly worse results in terms of Moorfields Regression Analysis (p = 0.027). Matrix showed significantly worse Mean Deviation (MD) (p = 0.000) and Pattern Standard Deviation (PSD) (p = 0.000) values and more altered Glaucoma Hemifield Test (p = 0.006) in AD patients. Pearson's R correlation test showed that Mini Mental State Examination is directly correlated with MD (R = 0.349; p = 0.034) and inversely correlated with PSD (R = −0.357; p = 0.030). Conclusion: Patients with AD have a higher frequency of glaucoma-like alterations, as detected by the use of HRT-3. These alterations were not associated with elevated IOP or abnormal CCT values. PMID:26733792

  2. Infection of Murine Macrophages by Salmonella enterica Serovar Heidelberg Blocks Murine Norovirus Infectivity and Virus-induced Apoptosis.

    PubMed

    Agnihothram, Sudhakar S; Basco, Maria D S; Mullis, Lisa; Foley, Steven L; Hart, Mark E; Sung, Kidon; Azevedo, Marli P

    2015-01-01

    Gastroenteritis caused by bacterial and viral pathogens constitutes a major public health threat in the United States accounting for 35% of hospitalizations. In particular, Salmonella enterica and noroviruses cause the majority of gastroenteritis infections, with emergence of sporadic outbreaks and incidence of increased infections. Although mechanisms underlying infections by these pathogens have been individually studied, little is known about the mechanisms regulating co-infection by these pathogens. In this study, we utilized RAW 264.7 murine macrophage cells to investigate the mechanisms governing co-infection with S. enterica serovar Heidelberg and murine norovirus (MNV). We demonstrate that infection of RAW 264.7 cells with S. enterica reduces the replication of MNV, in part by blocking virus entry early in the virus life cycle, and inducing antiviral cytokines later in the infection cycle. In particular, bacterial infection prior to, or during MNV infection affected virus entry, whereas MNV entry remained unaltered when the virus infection preceded bacterial invasion. This block in virus entry resulted in reduced virus replication, with the highest impact on replication observed during conditions of co-infection. In contrast, bacterial replication showed a threefold increase in MNV-infected cells, despite the presence of antibiotic in the medium. Most importantly, we present evidence that the infection of MNV-infected macrophages by S. enterica blocked MNV-induced apoptosis, despite allowing efficient virus replication. This apoptosis blockade was evidenced by reduction in DNA fragmentation and absence of poly-ADP ribose polymerase (PARP), caspase 3 and caspase 9 cleavage events. Our study suggests a novel mechanism of pathogenesis whereby initial co-infection with these pathogens could result in prolonged infection by either of these pathogens or both together. PMID:26658916

  3. The impact of education on risk factors and the occurrence of multimorbidity in the EPIC-Heidelberg cohort

    PubMed Central

    Nagel, Gabriele; Peter, Richard; Braig, Stefanie; Hermann, Silke; Rohrmann, Sabine; Linseisen, Jakob

    2008-01-01

    Background In aging populations, the prevalence of multimorbidity is high, and the role of socioeconomic status and its correlates is not well described. Thus, we investigated the association between educational attainment and multimorbidity in a prospective cohort study, taking also into account intermediate factors that could explain such associations. Methods We included 13,781 participants of the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC), who were 50–75 years at the end of follow-up. Information on diet and lifestyle was collected at recruitment (1994–1998). During a median follow-up of 8.7 years, information on chronic conditions and death were collected. Results Overall, the prevalence of multimorbidity (>= 2 concurrent chronic diseases) was 67.3%. Compared to the highest educational category, the lowest was statistically significantly associated with increased odds of multimorbidity in men (OR = 1.43; 95% CI 1.28–1.61) and women (OR = 1.33; 95% CI 1.18–1.57). After adjustment, the positive associations were attenuated (men: OR = 1.28; 95% CI 1.12–1.46; women: OR = 1.16; 95% CI 0.99–1.36). Increasing BMI was more strongly than smoking status an intermediate factor in the association between education and multimorbidity. Conclusion In this German population, the prevalence of multimorbidity is high and is significantly associated with educational level. Increasing BMI is the most important predictor of this association. However, even the fully adjusted model, i.e. considering also other known risk factors for chronic diseases, could not entirely explain socio-economic inequalities in multimorbidity. Educational level should be considered in the development and implementation of prevention strategies of multimorbidity. PMID:19014444

  4. Optic nerve head parameters of high-definition optical coherence tomography and Heidelberg retina tomogram in perimetric and preperimetric glaucoma

    PubMed Central

    Begum, Viquar Unnisa; Addepalli, Uday Kumar; Senthil, Sirisha; Garudadri, Chandra Sekhar; Rao, Harsha Laxmana

    2016-01-01

    Background: Heidelberg retina tomogram (HRT) and optical coherence tomography (OCT) are two widely used imaging modalities to evaluate the optic nerve head (ONH) in glaucoma. Purpose: To compare the ONH parameters of HRT3 and high-definition OCT (HD-OCT) and evaluate their diagnostic abilities in perimetric and preperimetric glaucoma. Design: Cross-sectional analysis. Methods: 35 control eyes (24 subjects), 21 preperimetric glaucoma eyes (15 patients), and 64 perimetric glaucoma eyes (44 patients) from the Longitudinal Glaucoma Evaluation Study underwent HRT3 and HD-OCT examinations. Statistical Analysis: Agreement between the ONH parameters of HRT and HD-OCT were assessed using Bland-Altman plots. Diagnostic abilities of ONH parameters were evaluated using area under the receiver operating characteristic curves (AUCs), sensitivity at fixed specificity, and likelihood ratios (LR). Results: Optic disc area, vertical cup to disc ratio, and cup volume with HD-OCT were larger than with HRT, while the rim area was smaller with HD-OCT (P < 0.001 for all comparisons). AUCs of all HD-OCT ONH parameters (0.90-0.97 in perimetric and 0.62-0.71 in preperimetric glaucoma) were comparable (P > 0.10) to the corresponding HRT ONH parameters (0.81-0.95 in perimetric and 0.55-0.72 in preperimetric glaucoma). LRs associated with diagnostic categorization of ONH parameters of both HD-OCT and HRT were associated with larger effects on posttest probability of perimetric compared to preperimetric glaucoma. Conclusions: ONH measurements of HD-OCT and HRT3 cannot be used interchangeably. Though the diagnostic abilities of ONH parameters of HD-OCT and HRT in glaucoma were comparable, the same were significantly lower in preperimetric compared to perimetric glaucoma. PMID:27221679

  5. Reproducibility of optic disk evaluation in supine subjects with a Heidelberg Retina Tomograph II laser tomographic scanner

    PubMed Central

    Harada, Yosuke; Akita, Tomoyuki; Takenaka, Joji; Nakamura-Kadohiro, Yuko; Tanaka, Junko; Kiuchi, Yoshiaki

    2016-01-01

    Aim The aim of this study was to determine the reproducibility and reliability of optic disk evaluation in supine subjects with a Heidelberg Retina Tomograph II (HRT II). Methods One eye was randomly selected for evaluation by HRT II in each of eleven healthy subjects. Five images were obtained by each of two experienced operators at two separate visits with the subjects in both sitting and supine positions. A stand was constructed to allow stable, handheld operation of the HRT II head for imaging of the supine subjects. Measurements of optic disk parameters obtained in the supine position were compared with those obtained in the sitting position. The reliability of measurements in the supine position was evaluated by calculating both the coefficients of variation for measurements made by one observer on the first visit and the interobserver and intervisit intraclass correlation coefficients (ICCs); the values obtained were compared with those obtained for the sitting position. Results Measurements of all parameters made in the supine position were highly similar to those made in the sitting position. The coefficients of variation obtained for each parameter in the sitting and supine positions ranged from 5.67% to 14.16% and from 2.18% to 16.08%, respectively. The interobserver ICC values in the sitting and supine positions were ≥0.978 and ≥0.989, respectively. The intervisit ICC values in the sitting and supine positions were ≥0.958 and ≥0.983, respectively. Conclusion Handheld operation of the HRT II in a custom-designed stand is feasible for optic disk evaluation in the supine subjects who were not able to maintain the sitting position. PMID:27601876

  6. Infection of Murine Macrophages by Salmonella enterica Serovar Heidelberg Blocks Murine Norovirus Infectivity and Virus-induced Apoptosis

    PubMed Central

    Agnihothram, Sudhakar S.; Basco, Maria D. S.; Mullis, Lisa; Foley, Steven L.; Hart, Mark E.; Sung, Kidon; Azevedo, Marli P.

    2015-01-01

    Gastroenteritis caused by bacterial and viral pathogens constitutes a major public health threat in the United States accounting for 35% of hospitalizations. In particular, Salmonella enterica and noroviruses cause the majority of gastroenteritis infections, with emergence of sporadic outbreaks and incidence of increased infections. Although mechanisms underlying infections by these pathogens have been individually studied, little is known about the mechanisms regulating co-infection by these pathogens. In this study, we utilized RAW 264.7 murine macrophage cells to investigate the mechanisms governing co-infection with S. enterica serovar Heidelberg and murine norovirus (MNV). We demonstrate that infection of RAW 264.7 cells with S. enterica reduces the replication of MNV, in part by blocking virus entry early in the virus life cycle, and inducing antiviral cytokines later in the infection cycle. In particular, bacterial infection prior to, or during MNV infection affected virus entry, whereas MNV entry remained unaltered when the virus infection preceded bacterial invasion. This block in virus entry resulted in reduced virus replication, with the highest impact on replication observed during conditions of co-infection. In contrast, bacterial replication showed a threefold increase in MNV-infected cells, despite the presence of antibiotic in the medium. Most importantly, we present evidence that the infection of MNV-infected macrophages by S. enterica blocked MNV-induced apoptosis, despite allowing efficient virus replication. This apoptosis blockade was evidenced by reduction in DNA fragmentation and absence of poly-ADP ribose polymerase (PARP), caspase 3 and caspase 9 cleavage events. Our study suggests a novel mechanism of pathogenesis whereby initial co-infection with these pathogens could result in prolonged infection by either of these pathogens or both together. PMID:26658916

  7. Natural and mixed convection in the cylindrical pool of TRIGA reactor

    NASA Astrophysics Data System (ADS)

    Henry, R.; Tiselj, I.; Matkovič, M.

    2016-05-01

    Temperature fields within the pool of the JSI TRIGA MARK II nuclear research reactor were measured to collect data for validation of the thermal hydraulics computational model of the reactor tank. In this context temperature of the coolant was measured simultaneously at sixty different positions within the pool during steady state operation and two transients. The obtained data revealed local peculiarities of the cooling water dynamics inside the pool and were used to estimate the coolant bulk velocity above the reactor core. Mixed natural and forced convection in the pool were simulated with a Computational Fluid Dynamics code. A relatively simple CFD model based on Unsteady RANS turbulence model was found to be sufficient for accurate prediction of the temperature fields in the pool during the reactor operation. Our results show that the simple geometry of the TRIGA pool reactor makes it a suitable candidate for a simple natural circulation benchmark in cylindrical geometry.

  8. Validation of neutron flux redistribution factors in JSI TRIGA reactor due to control rod movements.

    PubMed

    Kaiba, Tanja; Žerovnik, Gašper; Jazbec, Anže; Štancar, Žiga; Barbot, Loïc; Fourmentel, Damien; Snoj, Luka

    2015-10-01

    For efficient utilization of research reactors, such as TRIGA Mark II reactor in Ljubljana, it is important to know neutron flux distribution in the reactor as accurately as possible. The focus of this study is on the neutron flux redistributions due to control rod movements. For analyzing neutron flux redistributions, Monte Carlo calculations of fission rate distributions with the JSI TRIGA reactor model at different control rod configurations have been performed. Sensitivity of the detector response due to control rod movement have been studied. Optimal radial and axial positions of the detector have been determined. Measurements of the axial neutron flux distribution using the CEA manufactured fission chambers have been performed. The experiments at different control rod positions were conducted and compared with the MCNP calculations for a fixed detector axial position. In the future, simultaneous on-line measurements with multiple fission chambers will be performed inside the reactor core for a more accurate on-line power monitoring system. PMID:26141293

  9. Analysis of safety limits of the Moroccan TRIGA MARK II research reactor

    NASA Astrophysics Data System (ADS)

    Erradi, L.; Essadki, H.

    2001-06-01

    The main objective of this study is to check the ability of the Moroccan TRIGA MARK II research reactor, designed to use natural convection cooling, to operate at its nominal power (2 MW) with sufficient safety margins. The neutronic analysis of the core has been performed using Leopard and Mcrac codes and the parameters of interest were the power distributions, the power peaking factors and the core excess reactivity. The thermal hydraulic analysis of the TRIGA core was performed using the French code FLICA designed for transient and study state situations. The main safety related parameters of the core have been evaluated with special emphasises on the following: maximum fuel temperature, minimum DNBR and maximum void fraction. The obtained results confirm the designer predictions except for the void fraction.

  10. Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz

    NASA Astrophysics Data System (ADS)

    Karch, J.; Sobolev, Yu.; Beck, M.; Eberhardt, K.; Hampel, G.; Heil, W.; Kieser, R.; Reich, T.; Trautmann, N.; Ziegner, M.

    2014-04-01

    The performance of the solid deuterium ultra-cold neutron (UCN) source at the pulsed reactor TRIGA Mainz with a maximum peak energy of 10MJ is described. The solid deuterium converter with a volume of cm3 (8mol), which is exposed to a thermal neutron fluence of n/cm2, delivers up to 240000 UCN ( m/s) per pulse outside the biological shield at the experimental area. UCN densities of 10 cm3 are obtained in stainless-steel bottles of 10 L. The measured UCN yields compare well with the predictions from a Monte Carlo simulation developed to model the source and to optimize its performance for the upcoming upgrade of the TRIGA Mainz into a user facility for UCN physics.

  11. NASA Marshall Space Flight Center Tri-gas Thruster Performance Characterization

    NASA Technical Reports Server (NTRS)

    Dorado, Vanessa; Grunder, Zachary; Schaefer, Bryce; Sung, Meagan; Pedersen, Kevin

    2013-01-01

    Historically, spacecraft reaction control systems have primarily utilized cold gas thrusters because of their inherent simplicity and reliability. However, cold gas thrusters typically have a low specific impulse. It has been determined that a higher specific impulse can be achieved by passing a monopropellant fluid mixture through a catalyst bed prior to expulsion through the thruster nozzle. This research analyzes the potential efficiency improvements from using tri-gas, a mixture of hydrogen, oxygen, and an inert gas, which in this case is helium. Passing tri-gas through a catalyst causes the hydrogen and oxygen to react and form water vapor, ultimately heating the exiting fluid and generating a higher specific impulse. The goal of this project was to optimize the thruster performance by characterizing the effects of varying several system components including catalyst types, catalyst lengths, and initial catalyst temperatures.

  12. Verifying the Asymmetric Multiple Position Neutron Source (AMPNS) method using the TRIGA reactor

    SciTech Connect

    Kim, Soon-Sam; Leyine, S.H.

    1984-07-01

    A new experimental/analytical method has been developed using the Penn State Breazeale (TRIGA) reactor, to measure the k{sub eff} of a damaged core, e.g., the TMI-2 core, and unfold its k{sub infinity} distribution. This new method, the Asymmetric Multiple Position Neutron Source (AMPNS) method, uses the response of several neutron detectors in fixed positions around the core periphery (and possibly in the core) when a neutron source is placed sequentially in different discrete core positions. Experiments have been performed with the Penn State Breazeale TRIGA Reactor (PSBR) and analyzed with appropriate neutron calculations, using PSU-LEOPARD and EXTERMINATOR-II (EXT-II), to verify the method.

  13. Transport model based on three-dimensional cross-section generation for TRIGA core analysis

    SciTech Connect

    Kriangchaiporn, N.; Ivanov, K.; Haghighat, A.; Sears, C. F.

    2006-07-01

    The development of a three-dimensional (3-D) transport model for TRIGA core analysis based on the discrete ordinates (S{sub n}) method has been conducted. The effective fine- and broad- group structures for the TRIGA cross-section libraries were selected based on CPXSD (Contribution and Point-wise Cross-Section Driven) methodology. Different 3-D pin/core configurations are used to verify and validate the selected effective group structures. Thirteen-group structure was finally selected to be used for core analysis. The results agree with continuous energy cross-section Monte Carlo calculations for eigenvalues and normalized pin power distributions, which are used as a reference in this research. (authors)

  14. Experimental power density distribution benchmark in the TRIGA Mark II reactor

    SciTech Connect

    Snoj, L.; Stancar, Z.; Radulovic, V.; Podvratnik, M.; Zerovnik, G.; Trkov, A.; Barbot, L.; Domergue, C.; Destouches, C.

    2012-07-01

    In order to improve the power calibration process and to benchmark the existing computational model of the TRIGA Mark II reactor at the Josef Stefan Inst. (JSI), a bilateral project was started as part of the agreement between the French Commissariat a l'energie atomique et aux energies alternatives (CEA) and the Ministry of higher education, science and technology of Slovenia. One of the objectives of the project was to analyze and improve the power calibration process of the JSI TRIGA reactor (procedural improvement and uncertainty reduction) by using absolutely calibrated CEA fission chambers (FCs). This is one of the few available power density distribution benchmarks for testing not only the fission rate distribution but also the absolute values of the fission rates. Our preliminary calculations indicate that the total experimental uncertainty of the measured reaction rate is sufficiently low that the experiments could be considered as benchmark experiments. (authors)

  15. Validation of the Serpent 2 code on TRIGA Mark II benchmark experiments.

    PubMed

    Ćalić, Dušan; Žerovnik, Gašper; Trkov, Andrej; Snoj, Luka

    2016-01-01

    The main aim of this paper is the development and validation of a 3D computational model of TRIGA research reactor using Serpent 2 code. The calculated parameters were compared to the experimental results and to calculations performed with the MCNP code. The results show that the calculated normalized reaction rates and flux distribution within the core are in good agreement with MCNP and experiment, while in the reflector the flux distribution differ up to 3% from the measurements. PMID:26516989

  16. Analysis of JSI TRIGA MARK II reactor physical parameters calculated with TRIPOLI and MCNP.

    PubMed

    Henry, R; Tiselj, I; Snoj, L

    2015-03-01

    New computational model of the JSI TRIGA Mark II research reactor was built for TRIPOLI computer code and compared with existing MCNP code model. The same modelling assumptions were used in order to check the differences of the mathematical models of both Monte Carlo codes. Differences between the TRIPOLI and MCNP predictions of keff were up to 100pcm. Further validation was performed with analyses of the normalized reaction rates and computations of kinetic parameters for various core configurations. PMID:25576735

  17. Conceptual design of fuel transfer cask for Reactor TRIGA PUSPATI (RTP)

    NASA Astrophysics Data System (ADS)

    Muhamad, Shalina Sheik; Hamzah, Mohd Arif Arif B.

    2014-02-01

    Spent fuel transfer cask is used to transfer a spent fuel from the reactor tank to the spent fuel storage or for spent fuel inspection. Typically, the cask made from steel cylinders that are either welded or bolted closed. The cylinder is enclosed with additional steel, concrete, or other material to provide radiation shielding and containment of the spent fuel. This paper will discuss the Conceptual Design of fuel transfer cask for Reactor TRIGA Puspati (RTP).

  18. Production of {sup 99}Mo using LEU and molybdenum targets in a 1 MW Triga reactor

    SciTech Connect

    Mo, S.C.

    1993-12-31

    The production of {sup 99}Mo using Low Enriched Uranium (LEU) and natural molybdenum targets in a 1 MW Triga reactor is investigated. The successive linear programming technique is applied to minimize the target loadings for different yield constraints. The irradiation time is related to the kinetics of the growth and decay of {sup 99}Mo. The feasibility of a neutron generated based {sup 99}Mo production system is discussed.

  19. Conceptual design of fuel transfer cask for Reactor TRIGA PUSPATI (RTP)

    SciTech Connect

    Muhamad, Shalina Sheik; Hamzah, Mohd Arif Arif B.

    2014-02-12

    Spent fuel transfer cask is used to transfer a spent fuel from the reactor tank to the spent fuel storage or for spent fuel inspection. Typically, the cask made from steel cylinders that are either welded or bolted closed. The cylinder is enclosed with additional steel, concrete, or other material to provide radiation shielding and containment of the spent fuel. This paper will discuss the Conceptual Design of fuel transfer cask for Reactor TRIGA Puspati (RTP)

  20. STRUCTURAL CALCULATIONS FOR THE CODISPOSAL OF TRIGA SPENT NUCLEAR FUEL IN A WASTE PACKAGE

    SciTech Connect

    S. Mastilovic

    1999-07-28

    The purpose of this analysis is to determine the structural response of a TRIGA Department of Energy (DOE) spent nuclear fuel (SNF) codisposal canister placed in a 5-Defense High Level Waste (DHLW) waste package (WP) and subjected to a tipover design basis event (DBE) dynamic load; the results will be reported in terms of displacements and stress magnitudes. This activity is associated with the WP design.

  1. Conversion and evaluation of the THOR reactor core to TRIGA fuel elements

    SciTech Connect

    Li, S.-H.; Shiau, L.-C.

    1990-07-01

    The THOR reactor is a pool type 1 MW research reactor and has been operated since 1961. The original MTR fuel elements have been gradually replaced by TRIGA fuel elements since 1977 and the conversion completed in 1987. The calculations were performed for various core configurations by using computer codes, WIMS/CITATION. The computing results have been evaluated and compared with the core measurements after the fuel conversion. The analysis results are in good correspondence with the measurements. (author)

  2. Fundamental approach to TRIGA steady-state thermal-hydraulic CHF analysis.

    SciTech Connect

    Feldman, E.; Nuclear Engineering Division

    2008-03-30

    Methods are investigated for predicting the power at which critical heat flux (CHF) occurs in TRIGA reactors that rely on natural convection for primary flow. For a representative TRIGA reactor, two sets of functions are created. For the first set, the General Atomics STAT code and the more widely-used RELAP5-3D code are each employed to obtain reactor flow rate as a function of power. For the second set, the Bernath correlation, the 2006 Groeneveld table, the Hall and Mudawar outlet correlation, and each of the four PG-CHF correlations for rod bundles are used to predict the power at which CHF occurs as a function of channel flow rate. The two sets of functions are combined to yield predictions of the power at which CHF occurs in the reactor. A combination of the RELAP5-3D code and the 2006 Groeneveld table predicts 67% more CHF power than does a combination of the STAT code and the Bernath correlation. Replacing the 2006 Groeneveld table with the Bernath CHF correlation (while using the RELAP5-3D code flow solution) causes the increase to be 23% instead of 67%. Additional RELAP5-3D flow-versus-power solutions obtained from Reference 1 and presented in Appendix B for four specific TRIGA reactors further demonstrates that the Bernath correlation predicts CHF to occur at considerably lower power levels than does the 2006 Groeneveld table. Because of the lack of measured CHF data in the region of interest to TRIGA reactors, none of the CHF correlations considered can be assumed to provide the definitive CHF power. It is recommended, however, to compare the power levels of the potential limiting rods with the power levels at which the Bernath and 2006 Groeneveld CHF correlations predict CHF to occur.

  3. Role of decommissioning plan and its progress for the PUSPATI TRIGA Reactor

    SciTech Connect

    Zakaria, Norasalwa Mustafa, Muhammad Khairul Ariff Anuar, Abul Adli Idris, Hairul Nizam Ba'an, Rohyiza

    2014-02-12

    Malaysian nuclear research reactor, the PUSPATI TRIGA Reactor, reached its first criticality in 1982, and since then, it has been serving for more than 30 years for training, radioisotope production and research purposes. Realizing the age and the need for its decommissioning sometime in the future, a ground basis of assessment and an elaborative project management need to be established, covering the entire process from termination of reactor operation to the establishment of final status, documented as the Decommissioning Plan. At international level, IAEA recognizes the absence of Decommissioning Plan as one of the factors hampering progress in decommissioning of nuclear facilities in the world. Throughout the years, IAEA has taken initiatives and drawn out projects in promoting progress in decommissioning programmes, like CIDER, DACCORD and R2D2P, for which Malaysia is participating in these projects. This paper highlights the concept of Decommissioning plan and its significances to the Agency. It will also address the progress, way forward and challenges faced in developing the Decommissioning Plan for the PUSPATI TRIGA Reactor. The efforts in the establishment of this plan helps to provide continual national contribution at the international level, as well as meeting the regulatory requirement, if need be. The existing license for the operation of PUSPATI TRIGA Reactor does not impose a requirement for a decommissioning plan; however, the renewal of license may call for a decommissioning plan to be submitted for approval in future.

  4. Neutron flux characterisation of the Pavia TRIGA Mark II research reactor for radiobiological and microdosimetric applications.

    PubMed

    Alloni, D; Prata, M; Salvini, A; Ottolenghi, A

    2015-09-01

    Nowadays the Pavia TRIGA reactor is available for national and international collaboration in various research fields. The TRIGA Mark II nuclear research reactor of the Pavia University offers different in- and out-core neutron irradiation channels, each characterised by different neutron spectra. In the last two years a campaign of measurements and simulations has been performed in order to guarantee a better characterisation of these different fluxes and to meet the demands of irradiations that require precise information on these spectra in particular for radiobiological and microdosimetric studies. Experimental data on neutron fluxes have been collected analysing and measuring the gamma activity induced in thin target foils of different materials irradiated in different TRIGA experimental channels. The data on the induced gamma activities have been processed with the SAND II deconvolution code and finally compared with the spectra obtained with Monte Carlo simulations. The comparison between simulated and measured spectra showed a good agreement allowing a more precise characterisation of the neutron spectra and a validation of the adopted method. PMID:25958412

  5. Fluid Flow Characteristic Simulation of the Original TRIGA 2000 Reactor Design Using Computational Fluid Dynamics Code

    NASA Astrophysics Data System (ADS)

    Fiantini, Rosalina; Umar, Efrizon

    2010-06-01

    Common energy crisis has modified the national energy policy which is in the beginning based on natural resources becoming based on technology, therefore the capability to understanding the basic and applied science is needed to supporting those policies. National energy policy which aims at new energy exploitation, such as nuclear energy is including many efforts to increase the safety reactor core condition and optimize the related aspects and the ability to build new research reactor with properly design. The previous analysis of the modification TRIGA 2000 Reactor design indicates that forced convection of the primary coolant system put on an effect to the flow characteristic in the reactor core, but relatively insignificant effect to the flow velocity in the reactor core. In this analysis, the lid of reactor core is closed. However the forced convection effect is still presented. This analysis shows the fluid flow velocity vector in the model area without exception. Result of this analysis indicates that in the original design of TRIGA 2000 reactor, there is still forced convection effects occur but less than in the modified TRIGA 2000 design.

  6. Role of decommissioning plan and its progress for the PUSPATI TRIGA Reactor

    NASA Astrophysics Data System (ADS)

    Zakaria, Norasalwa; Mustafa, Muhammad Khairul Ariff; Anuar, Abul Adli; Idris, Hairul Nizam; Ba'an, Rohyiza

    2014-02-01

    Malaysian nuclear research reactor, the PUSPATI TRIGA Reactor, reached its first criticality in 1982, and since then, it has been serving for more than 30 years for training, radioisotope production and research purposes. Realizing the age and the need for its decommissioning sometime in the future, a ground basis of assessment and an elaborative project management need to be established, covering the entire process from termination of reactor operation to the establishment of final status, documented as the Decommissioning Plan. At international level, IAEA recognizes the absence of Decommissioning Plan as one of the factors hampering progress in decommissioning of nuclear facilities in the world. Throughout the years, IAEA has taken initiatives and drawn out projects in promoting progress in decommissioning programmes, like CIDER, DACCORD and R2D2P, for which Malaysia is participating in these projects. This paper highlights the concept of Decommissioning plan and its significances to the Agency. It will also address the progress, way forward and challenges faced in developing the Decommissioning Plan for the PUSPATI TRIGA Reactor. The efforts in the establishment of this plan helps to provide continual national contribution at the international level, as well as meeting the regulatory requirement, if need be. The existing license for the operation of PUSPATI TRIGA Reactor does not impose a requirement for a decommissioning plan; however, the renewal of license may call for a decommissioning plan to be submitted for approval in future.

  7. Transition from HEU to LEU fuel in Romania's 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.; Snelgrove, J.L.

    1991-01-01

    The 14-MW TRIGA steady state reactor (SSR) located in Pitesti, Romania, first went critical in the fall of 1979. Initially, the core configuration for full power operation used 29 fuel clusters each containing a 5 {times} 5 square array of HEU (10 wt%) -- ZrH -- Er (2.8 wt%) fuel-moderator rods (1.295 cm o.d.) clad in Incology. With a total inventory of 35 HEU fuel clusters, burnup considerations required a gradual expansion of the core from 29 to 32 and finally to 35 clusters before the reactor was shut down because of insufficient excess reactivity. At this time each of the original 29 fuel clusters had an overage {sup 235}U burnup in the range from 50 to 62%. Because of the US policy regarding the export of highly enriched uranium, fresh HEU TRIGA replacement fuel is not available. After a number of safety-related measurements, the SSR is expected to resume full power operation in the near future using a mixed core containing five LEU TRIGA clusters of the same geometry as the original fuel but with fuel-moderator rods containing 45 wt% U (19.7% {sup 235}U enrichment) and 1.1 wt% Er. Rods for 14 additional LEU fuel clusters will be fabricated by General Atomics. In support of the SSR mixed core operation numerous neutronic calculations have been performed. This paper presents some of the results of those calculations.

  8. Transition from HEU to LEU fuel in Romania`s 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.; Snelgrove, J.L.

    1991-12-31

    The 14-MW TRIGA steady state reactor (SSR) located in Pitesti, Romania, first went critical in the fall of 1979. Initially, the core configuration for full power operation used 29 fuel clusters each containing a 5 {times} 5 square array of HEU (10 wt%) -- ZrH -- Er (2.8 wt%) fuel-moderator rods (1.295 cm o.d.) clad in Incology. With a total inventory of 35 HEU fuel clusters, burnup considerations required a gradual expansion of the core from 29 to 32 and finally to 35 clusters before the reactor was shut down because of insufficient excess reactivity. At this time each of the original 29 fuel clusters had an overage {sup 235}U burnup in the range from 50 to 62%. Because of the US policy regarding the export of highly enriched uranium, fresh HEU TRIGA replacement fuel is not available. After a number of safety-related measurements, the SSR is expected to resume full power operation in the near future using a mixed core containing five LEU TRIGA clusters of the same geometry as the original fuel but with fuel-moderator rods containing 45 wt% U (19.7% {sup 235}U enrichment) and 1.1 wt% Er. Rods for 14 additional LEU fuel clusters will be fabricated by General Atomics. In support of the SSR mixed core operation numerous neutronic calculations have been performed. This paper presents some of the results of those calculations.

  9. Gross Gamma Dose Rate Measurements for TRIGA Spent Nuclear Fuel Burnup Validation

    SciTech Connect

    Winston, Philip Lon; Sterbentz, James William

    2001-04-01

    Gross gamma-ray dose rates from six spent TRIGA fuel elements were measured and compared to calculated values as a means to validate the reported element burnups. A newly installed and functional gamma-ray detection subsystem of the In-Cell Examination System was used to perform the measurements and is described in some detail. The analytical methodology used to calculate the corresponding dose rates is presented along with the calculated values. Comparison of the measured and calculated dose rates for the TRIGA fuel elements indicates good agreement (less than a factor of 2 difference). The intent of the subsystem is to measure the gross gamma dose rate and correlate the measurement to a calculated dose rate based on the element s known burnup and other pertinent spent fuel information. Although validation of the TRIGA elements’ burnup is of primary concern in this paper, the measurement and calculational techniques can be used to either validate an element’s reported burnup or provide a burnup estimate for an element with an unknown burnup.

  10. NATCRCTR: One-dimensional thermal-hydraulics analysis code for natural-circulation TRIGA reactors

    SciTech Connect

    Feltus, M.A.; Rubinaccio, G.

    1996-12-31

    The Pennsylvania State University nuclear engineering department is evaluating the upgrade of the Reed College (Portland, Oregon) TRIGA reactor from 250 kW to 1 MW in two areas: thermal-hydraulics and steady-state neutronics analysis. This analysis was initiated as a cooperative effort between Penn State and Reed College as a training project for two International Atomic Energy Agency (IAEA) fellows from Ghana. The two Ghanaian IAEA fellows were assisted by G. Rubinaccio, an undergraduate, who undertook the task of writing the new computer programs for the thermal-hydraulic and physics evaluation as a three-credit special design project course. The Reed College TRIGA, which has a fixed graphite radial reflector, is cooled by natural circulation, without external cross-flow; whereas, the Penn State Breazeale Reactor has significant crossflow into its sides. To model the Reed TRIGA, the NATCRCTR program has been developed from first principles using the following assumptions: 1. The core is surrounded by the fixed reflector structure, which acts as a one-dimensional channel. 2. The core inlet temperature distribution is constant at the core bottom. 3. The axial heat flux distribution is a chopped cosine shape. 4. The heat transfer in the fuel is primarily in the radial directions. 5. A small gap between the fuel and cladding exists. The NATCRCTR code is used to find the peak centerline fuel, gap, and cladding surface temperatures, based on assumed flux and engineering peaking factors.

  11. Gross Gamma Dose Rate Measurements for TRIGA Spent Nuclear Fuel Burnup Validation

    SciTech Connect

    Winston, P.L.; Sterbentz, J.W.

    2002-07-01

    Gross gamma-ray dose rates from six spent TRIGA fuel elements were measured and compared to calculated values as a means to validate the reported element burnups. A newly installed and functional gamma-ray detection subsystem of the In-Cell Examination System was used to perform the measurements and is described in some detail. The analytical methodology used to calculate the corresponding dose rates is presented along with the calculated values. Comparison of the measured and calculated dose rates for the TRIGA fuel elements indicates good agreement (less than a factor of 2 difference). The intent of the subsystem is to measure the gross gamma dose rate and correlate the measurement to a calculated dose rate based on the element s known burnup and other pertinent spent fuel information. Although validation of the TRIGA elements' burnup is of primary concern in this paper, the measurement and calculational techniques can be used to either validate an element's reported burnup or provide a burnup estimate for an element with an unknown burnup. (authors)

  12. Fluid Flow Characteristic Simulation of the Original TRIGA 2000 Reactor Design Using Computational Fluid Dynamics Code

    SciTech Connect

    Fiantini, Rosalina; Umar, Efrizon

    2010-06-22

    Common energy crisis has modified the national energy policy which is in the beginning based on natural resources becoming based on technology, therefore the capability to understanding the basic and applied science is needed to supporting those policies. National energy policy which aims at new energy exploitation, such as nuclear energy is including many efforts to increase the safety reactor core condition and optimize the related aspects and the ability to build new research reactor with properly design. The previous analysis of the modification TRIGA 2000 Reactor design indicates that forced convection of the primary coolant system put on an effect to the flow characteristic in the reactor core, but relatively insignificant effect to the flow velocity in the reactor core. In this analysis, the lid of reactor core is closed. However the forced convection effect is still presented. This analysis shows the fluid flow velocity vector in the model area without exception. Result of this analysis indicates that in the original design of TRIGA 2000 reactor, there is still forced convection effects occur but less than in the modified TRIGA 2000 design.

  13. Transport model based on three-dimensional cross-section generation for TRIGA core analysis

    NASA Astrophysics Data System (ADS)

    Kriangchaiporn, Nateekool

    This dissertation addresses the development of a reactor core physics model based on 3-D transport methodology utilizing 3-D multigroup fuel lattice cross-section generation and core calculation for PSBR. The proposed 3-D transport calculation scheme for reactor core simulations is based on the TORT code. The methodology includes development of algorithms for 2-D and 3-D cross-section generation. The fine- and broad-group structures for the TRIGA cross-section generation problems were developed based on the CPXSD (Contributon and Point-wise Cross-Section Driven) methodology that selects effective group structure. Along with the study of cross section generation, the parametric studies for SN calculations were performed to evaluate the impact of the spatial meshing, angular, and scattering order variables and to obtain the suitable values for cross-section collapsing of the TRIGA cell problem. The TRIGA core loading 2 is used to verify and validate the selected effective group structures. Finally, the 13 group structure was selected to use for core calculations. The results agree with continuous energy for eigenvalues and normalized pin power distribution. The Monte Carlo solutions are used as the references.

  14. Effect of Photorefractive Keratectomy on Optic Nerve Head Topography and Retinal Nerve Fiber Layer Thickness Measured by Heidelberg Retina Tomograph 3

    PubMed Central

    Nilforushan, Naveed; Azadi, Pejvak; Soudi, Reza; Shaheen, Yahya; Sheibani, Kourosh

    2016-01-01

    Purpose: To determine whether photorefractive keratectomy (PRK) has a significant effect on optic nerve head (ONH) parameters and peripapillary retinal nerve fiber layer (RNFL) thickness measured by the Heidelberg Retina Tomograph 3 (Heidelberg Engineering GmbH, Heidelberg, Germany) in eyes with low to moderate myopia. Methods: This prospective, interventional case series, includes 43 consecutive myopic eyes which were assessed on the day of PRK and 3 months postoperatively using the HRT3. Among the stereometric parameters, we compared disc area, linear cup disc ratio, cup shape measure, global rim area, global rim volume, RNFL height variation contour and mean RNFL thickness; out of the Glaucoma Probability Score (GPS) we assessed changes in global value, rim steepness temporal/superior, and temporal/inferior, as well as cup size and cup depth before and after PRK. Results: Mean refractive error before and after PRK were −3.24 ± 1.31 and −0.20 ± 0.42 diopters, respectively. No significant change occurred in disc area, linear cup disc ratio, cup shape measure, rim area and rim volume among the stereometric parameters; and in rim steepness temporal/superior and rim steepness temporal/inferior in the GPS before and after PRK using the default average keratometry. However, RNFL height variation contour, mean RNFL thickness, and cup size and depth were significantly altered after PRK (P < 0.05). Conclusion: PRK can affect some HRT3 parameters. Although the most important stereometric parameters for differentiating normal, suspect or glaucomatous patients such as rim and cup measurements in stereometric parameters were not changed. PMID:27413492

  15. Retinal Nerve Fiber and Optic Disc Morphology in Patients with Human Immunodeficiency Virus Using the Heidelberg Retina Tomography 3

    PubMed Central

    Bartsch, Dirk-Uwe; Kozak, Igor; Grant, Igor; Knudsen, Victoria L.; Weinreb, Robert N.; Lee, Byung Ro; Freeman, William R.

    2015-01-01

    Purpose To use novel confocal scanning ophthalmoscopy technology to test hypothesis that HIV-seropositive patients without history of retinitis with a history of a low CD4 count are more likely to have damage to their retinal nerve fiber layer (RNFL) when compared to patients with high CD4 count. In addition, we compared optic disc morphologic changes with glaucoma. Design Cross-sectional study. Participants and Controls 171 patients were divided into four groups. The control group consisted of 40 eyes of 20 HIV-seronegative patients. The second group consisted of 80 eyes of 41 HIV-positive patients whose CD4 cell count never dropped below 100 (1.0 x 109/L). The third group consisted of 44 eyes of 26 HIV-positive patients with a history of low CD4 counts <100. Fourth group consisted of 79 eyes of 79 patients with confirmed glaucoma who served as positive controls. Testing Confocal scanning laser ophthalmoscopy was performed with the Heidelberg Retina Tomograph (HRT3) and data were analyzed with HRT3, software (Heyex version 1.5.10.0). Main Outcome Measures Disc area, cup area, cup volume, rim volume, mean cup depth, maximum cup depth, cup-to-disc ration, mean RNFL thickness, and RNFL cross-sectional area. Results Analysis of the global optic nerve and cup parameters showed no difference in disk area among the four groups. There was also no difference in cup, rim volume, mean cup depth, or maximum cup depth among the first three groups but they were all different from glaucoma group. The RNFL was thinner in glaucoma and both HIV-positive groups compared to HIV-seronegative subjects. The cross sectional RNFL area was thinner in both high and low CD4 HIV-positive groups compared to HIV-seronegative group in the nasal and temporal/inferior sectors, respectively. Glaucoma group showed thinning in all sectors. Conclusions HIV retinopathy results in retinal nerve fiber layer loss without structural optic nerve supportive tissue change. RNFL damage may occur early in HIV

  16. First experimental-based characterization of oxygen ion beam depth dose distributions at the Heidelberg Ion-Beam Therapy Center

    NASA Astrophysics Data System (ADS)

    Kurz, C.; Mairani, A.; Parodi, K.

    2012-08-01

    Over the last decades, the application of proton and heavy-ion beams to external beam radiotherapy has rapidly increased. Due to the favourable lateral and depth dose profile, the superposition of narrow ion pencil beams may enable a highly conformal dose delivery to the tumour, with better sparing of the surrounding healthy tissue in comparison to conventional radiation therapy with photons. To fully exploit the promised clinical advantages of ion beams, an accurate planning of the patient treatments is required. The clinical treatment planning system (TPS) at the Heidelberg Ion-Beam Therapy Center (HIT) is based on a fast performing analytical algorithm for dose calculation, relying, among others, on laterally integrated depth dose distributions (DDDs) simulated with the FLUKA Monte Carlo (MC) code. Important input parameters of these simulations need to be derived from a comparison of the simulated DDDs with measurements. In this work, the first measurements of 16O ion DDDs at HIT are presented with a focus on the determined Bragg peak positions and the understanding of factors influencing the shape of the distributions. The measurements are compared to different simulation approaches aiming to reproduce the acquired data at best. A simplified geometrical model is first used to optimize important input parameters, not known a priori, in the simulations. This method is then compared to a more realistic, but also more time-consuming simulation approach better accounting for the experimental set-up and the measuring process. The results of this work contributed to a pre-clinical oxygen ion beam database, which is currently used by a research TPS for corresponding radio-biological cell experiments. A future extension to a clinical database used by the clinical TPS at HIT is foreseen. As a side effect, the performed investigations showed that the typical water equivalent calibration approach of experimental data acquired with water column systems leads to slight

  17. First experimental-based characterization of oxygen ion beam depth dose distributions at the Heidelberg Ion-Beam Therapy Center.

    PubMed

    Kurz, C; Mairani, A; Parodi, K

    2012-08-01

    Over the last decades, the application of proton and heavy-ion beams to external beam radiotherapy has rapidly increased. Due to the favourable lateral and depth dose profile, the superposition of narrow ion pencil beams may enable a highly conformal dose delivery to the tumour, with better sparing of the surrounding healthy tissue in comparison to conventional radiation therapy with photons. To fully exploit the promised clinical advantages of ion beams, an accurate planning of the patient treatments is required. The clinical treatment planning system (TPS) at the Heidelberg Ion-Beam Therapy Center (HIT) is based on a fast performing analytical algorithm for dose calculation, relying, among others, on laterally integrated depth dose distributions (DDDs) simulated with the FLUKA Monte Carlo (MC) code. Important input parameters of these simulations need to be derived from a comparison of the simulated DDDs with measurements. In this work, the first measurements of (16)O ion DDDs at HIT are presented with a focus on the determined Bragg peak positions and the understanding of factors influencing the shape of the distributions. The measurements are compared to different simulation approaches aiming to reproduce the acquired data at best. A simplified geometrical model is first used to optimize important input parameters, not known a priori, in the simulations. This method is then compared to a more realistic, but also more time-consuming simulation approach better accounting for the experimental set-up and the measuring process. The results of this work contributed to a pre-clinical oxygen ion beam database, which is currently used by a research TPS for corresponding radio-biological cell experiments. A future extension to a clinical database used by the clinical TPS at HIT is foreseen. As a side effect, the performed investigations showed that the typical water equivalent calibration approach of experimental data acquired with water column systems leads to slight

  18. Phase Space Generation for Proton and Carbon Ion Beams for External Users’ Applications at the Heidelberg Ion Therapy Center

    PubMed Central

    Tessonnier, Thomas; Marcelos, Tiago; Mairani, Andrea; Brons, Stephan; Parodi, Katia

    2016-01-01

    In the field of radiation therapy, accurate and robust dose calculation is required. For this purpose, precise modeling of the irradiation system and reliable computational platforms are needed. At the Heidelberg Ion Therapy Center (HIT), the beamline has been already modeled in the FLUKA Monte Carlo (MC) code. However, this model was kept confidential for disclosure reasons and was not available for any external team. The main goal of this study was to create efficiently phase space (PS) files for proton and carbon ion beams, for all energies and foci available at HIT. PSs are representing the characteristics of each particle recorded (charge, mass, energy, coordinates, direction cosines, generation) at a certain position along the beam path. In order to achieve this goal, keeping a reasonable data size but maintaining the requested accuracy for the calculation, we developed a new approach of beam PS generation with the MC code FLUKA. The generated PSs were obtained using an infinitely narrow beam and recording the desired quantities after the last element of the beamline, with a discrimination of primaries or secondaries. In this way, a unique PS can be used for each energy to accommodate the different foci by combining the narrow-beam scenario with a random sampling of its theoretical Gaussian beam in vacuum. PS can also reproduce the different patterns from the delivery system, when properly combined with the beam scanning information. MC simulations using PS have been compared to simulations, including the full beamline geometry and have been found in very good agreement for several cases (depth dose distributions, lateral dose profiles), with relative dose differences below 0.5%. This approach has also been compared with measured data of ion beams with different energies and foci, resulting in a very satisfactory agreement. Hence, the proposed approach was able to fulfill the different requirements and has demonstrated its capability for application to

  19. Genomic Comparison of Non-Typhoidal Salmonella enterica Serovars Typhimurium, Enteritidis, Heidelberg, Hadar and Kentucky Isolates from Broiler Chickens

    PubMed Central

    Dhanani, Akhilesh S.; Block, Glenn; Dewar, Ken; Forgetta, Vincenzo; Topp, Edward; Beiko, Robert G.; Diarra, Moussa S.

    2015-01-01

    Background Non-typhoidal Salmonella enterica serovars, associated with different foods including poultry products, are important causes of bacterial gastroenteritis worldwide. The colonization of the chicken gut by S. enterica could result in the contamination of the environment and food chain. The aim of this study was to compare the genomes of 25 S. enterica serovars isolated from broiler chicken farms to assess their intra- and inter-genetic variability, with a focus on virulence and antibiotic resistance characteristics. Methodology/Principal Finding The genomes of 25 S. enterica isolates covering five serovars (ten Typhimurium including three monophasic 4,[5],12:i:, four Enteritidis, three Hadar, four Heidelberg and four Kentucky) were sequenced. Most serovars were clustered in strongly supported phylogenetic clades, except for isolates of serovar Enteritidis that were scattered throughout the tree. Plasmids of varying sizes were detected in several isolates independently of serovars. Genes associated with the IncF plasmid and the IncI1 plasmid were identified in twelve and four isolates, respectively, while genes associated with the IncQ plasmid were found in one isolate. The presence of numerous genes associated with Salmonella pathogenicity islands (SPIs) was also confirmed. Components of the type III and IV secretion systems (T3SS and T4SS) varied in different isolates, which could explain in part, differences of their pathogenicity in humans and/or persistence in broilers. Conserved clusters of genes in the T3SS were detected that could be used in designing effective strategies (diagnostic, vaccination or treatments) to combat Salmonella. Antibiotic resistance genes (CMY, aadA, ampC, florR, sul1, sulI, tetAB, and srtA) and class I integrons were detected in resistant isolates while all isolates carried multidrug efflux pump systems regardless of their antibiotic susceptibility profile. Conclusions/Significance This study showed that the predominant

  20. Comparison of methods for quantitating Salmonella enterica Typhimurium and Heidelberg strain attachment to reusable plastic shipping container coupons and preliminary assessment of sanitizer efficacy.

    PubMed

    Shi, Zhaohao; Baker, Christopher A; Lee, Sang In; Park, Si Hong; Kim, Sun Ae; Ricke, Steven C

    2016-09-01

    Salmonella serovars, one of the leading contributors to foodborne illness and are especially problematic for foods that are not cooked before consumption, such as fresh produce. The shipping containers that are used to transport and store fresh produce may play a role in cross contamination and subsequent illnesses. However, methods for quantitatively attached cells are somewhat variable. The overall goal of this study was to compare conventional plating with molecular methods for quantitating attached representative strains for Salmonella Typhimurium and Heidelberg on reusable plastic containers (RPC) coupons, respectively. We attached Salmonella enterica serovar Typhimurium ATCC 14028 and serovar Heidelberg SL486 (parent and an antibiotic resistant marker strain) to plastic coupons (2.54 cm(2)) derived from previously used shipping containers by growing for 72 h in tryptic soy broth. The impact of the concentration of sanitizer on log reductions between unsanitized and sanitized coupons was evaluated by exposing attached S. Typhimurium cells to 200 ppm and 200,000 ppm sodium hypochlorite (NaClO). Differences in sanitizer effectiveness between serovars were also evaluated with attached S. Typhimurium compared to attached S. Heidelberg populations after being exposed to 200 ppm peracetic acid (PAA). Treatment with NaClO caused an average of 2.73 ± 0.23 log CFU of S. Typhimurium per coupon removed with treatment at 200 ppm while 3.36 ± 0.54 log CFU were removed at 200,000 ppm. Treatment with PAA caused an average of 2.62 ± 0.15 log CFU removed for S. Typhimurium and 1.41 ± 0.17 log CFU for S. Heidelberg (parent) and 1.61 ± 0.08 log CFU (marker). Lastly, scanning electron microscopy (SEM) was used to visualize cell attachment and coupon surface topography. SEM images showed that remaining attached cell populations were visible even after sanitizer application. Conventional plating and qPCR yielded similar levels of enumerated bacterial populations

  1. The history and perspective of Romania-USA cooperation in the field of technologic transfer of TRIGA reactor concept

    SciTech Connect

    Ciocaanescu, M.; Ionescu, M.

    1996-08-01

    The cooperation between Romania and the USA in the field of technologic transfer of nuclear research reactor technology began with the steady state 14 MW{sub t} TRIGA reactor, installed at INR Pitesti, Romania. It is the first in the range of TRIGA reactors proposed as a materials testing reactor. The first criticality was reached in November 19, 1979 and first operation at 14 MW{sub t} level was in February 1980. The paper will present the short history of this cooperation and the perspective for a new cooperation for building a Nuclear Heating Plant using the TRIGA reactor concept for demonstration purpose. The energy crisis is a world-wide problem which affects each country in different ways because the resources and the consumption are unfairly distributed. World-wide research points out that the fossil fuel sources are not to be considered the main energy sources for the long term as they are limited.

  2. High-temperature Chemical Compatibility of As-fabricated TRIGA Fuel and Type 304 Stainless Steel Cladding

    SciTech Connect

    Dennis D. Keiser, Jr.; Jan-Fong Jue; Eric Woolstenhulme; Kurt Terrani; Glenn A. Moore

    2012-09-01

    Chemical interaction between TRIGA fuel and Type-304 stainless steel cladding at relatively high temperatures is of interest from the point of view of understanding fuel behavior during different TRIGA reactor transient scenarios. Since TRIGA fuel comes into close contact with the cladding during irradiation, there is an opportunity for interdiffusion between the U in the fuel and the Fe in the cladding to form an interaction zone that contains U-Fe phases. Based on the equilibrium U-Fe phase diagram, a eutectic can develop at a composition between the U6Fe and UFe2 phases. This eutectic composition can become a liquid at around 725°C. From the standpoint of safe operation of TRIGA fuel, it is of interest to develop better understanding of how a phase with this composition may develop in irradiated TRIGA fuel at relatively high temperatures. One technique for investigating the development of a eutectic phase at the fuel/cladding interface is to perform out-of-pile diffusion-couple experiments at relatively high temperatures. This information is most relevant for lightly irradiated fuel that just starts to touch the cladding due to fuel swelling. Similar testing using fuel irradiated to different fission densities should be tested in a similar fashion to generate data more relevant to more heavily irradiated fuel. This report describes the results for TRIGA fuel/Type-304 stainless steel diffusion couples that were annealed for one hour at 730 and 800°C. Scanning electron microscopy with energy- and wavelength-dispersive spectroscopy was employed to characterize the fuel/cladding interface for each diffusion couple to look for evidence of any chemical interaction. Overall, negligible fuel/cladding interaction was observed for each diffusion couple.

  3. Development of TRIGA-based experimental device for fiber optics in-core instrumentation testing for VHTRs

    SciTech Connect

    Johns, J. M.; Tsvetkov, P. V.

    2012-07-01

    Given the harsh environments of high temperature reactors, new in-core instrumentation has to be developed, since existing approaches may fail prematurely in VHTRs. The paper discusses ongoing efforts to support progress of suitable advanced in-core instrumentation technologies and develop an experimental approach for evaluation of their performance within VHTRs via emulation of VHTR in-core conditions in TRIGA reactors. Successful completion of the presented computational analysis concludes the first phase of the project. As demonstrated, it is proposed to use a high temperature furnace with fluence equivalency in operating TRIGA reactors. (authors)

  4. Assessment results of the South Korea TRIGA SNF to be shipped to INEEL

    SciTech Connect

    Cole, C.M.; Dirk, W.J.; Cottam, R.E.; Paik, S.T.

    1997-10-09

    This paper describes the Training, Research, Isotope, General Atomics (TRIGA) spent nuclear fuel (SNF) examination at the Seoul and the Taejon Research Reactor Facilities in South Korea. The examination was required before the SNF would be accepted for transportation and storage at the INEEL. The results of the aluminum and stainless steel clad TRIGA fuel examination have been summarized. A description of the examination team training, the examination work plan and examination equipment is also included. This paper also explains the technical basis for the examination and physical condition criteria used to determine what, if any, additional packaging would be required for transportation and for the receipt and storage of the fuel at the INEEL. This paper delineates the preparation activities prior to the fuel examinations and includes (1) collecting spent fuel data; (2) preparatory work by the Korean Atomic Energy Research Institute (KAERI) for fuel examination: (3) preparation of a radionuclide report, Radionuclide Mass Inventory, Activity, Decay Heat, and Dose Rate Parametric Data for TRIGA Spent Nuclear Fuels needed to provide input data for transportation and fuel acceptance at the Idaho National Engineering and Environmental Laboratory (INEEL); (4) gathering FRR Facility data; and (5) coordination between the INEEL and KAERI. Included, are the unanticipated conditions encountered in the unloading of fuel from the dry storage casks in Taejon in preparation for examination, a description of the damaged condition of the fuel removed from the casks, and the apparent cause of the damages. Lessons learned from all the activities are also addressed. A brief description of the preparatory work for the shipment of the spent fuel from Korea to INEEL is included.

  5. Monte Carlo Simulation of the TRIGA Mark II Benchmark Experiment with Burned Fuel

    SciTech Connect

    Jeraj, Robert; Zagar, Tomaz; Ravnik, Matjaz

    2002-03-15

    Monte Carlo calculations of a criticality experiment with burned fuel on the TRIGA Mark II research reactor are presented. The main objective was to incorporate burned fuel composition calculated with the WIMSD4 deterministic code into the MCNP4B Monte Carlo code and compare the calculated k{sub eff} with the measurements. The criticality experiment was performed in 1998 at the ''Jozef Stefan'' Institute TRIGA Mark II reactor in Ljubljana, Slovenia, with the same fuel elements and loading pattern as in the TRIGA criticality benchmark experiment with fresh fuel performed in 1991. The only difference was that in 1998, the fuel elements had on average burnup of {approx}3%, corresponding to 1.3-MWd energy produced in the core in the period between 1991 and 1998. The fuel element burnup accumulated during 1991-1998 was calculated with the TRIGLAV in-house-developed fuel management two-dimensional multigroup diffusion code. The burned fuel isotopic composition was calculated with the WIMSD4 code and compared to the ORIGEN2 calculations. Extensive comparison of burned fuel material composition was performed for both codes for burnups up to 20% burned {sup 235}U, and the differences were evaluated in terms of reactivity. The WIMSD4 and ORIGEN2 results agreed well for all isotopes important in reactivity calculations, giving increased confidence in the WIMSD4 calculation of the burned fuel material composition. The k{sub eff} calculated with the combined WIMSD4 and MCNP4B calculations showed good agreement with the experimental values. This shows that linking of WIMSD4 with MCNP4B for criticality calculations with burned fuel is feasible and gives reliable results.

  6. Modification of the radial beam port of ITU TRIGA Mark II research reactor for BNCT applications.

    PubMed

    Akan, Zafer; Türkmen, Mehmet; Çakir, Tahir; Reyhancan, İskender A; Çolak, Üner; Okka, Muhittin; Kiziltaş, Sahip

    2015-05-01

    This paper aims to describe the modification of the radial beam port of ITU (İstanbul Technical University) TRIGA Mark II research reactor for BNCT applications. Radial beam port is modified with Polyethylene and Cerrobend collimators. Neutron flux values are measured by neutron activation analysis (Au-Cd foils). Experimental results are verified with Monte Carlo results. The results of neutron/photon spectrum, thermal/epithermal neutron flux, fast group photon fluence and change of the neutron fluxes with the beam port length are presented. PMID:25746919

  7. Determination of the irradiation field at the research reactor TRIGA Mainz for BNCT.

    PubMed

    Nagels, S; Hampel, G; Kratz, J V; Aguilar, A L; Minouchehr, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L; Wortmann, B

    2009-07-01

    For the application of the BNCT for the excorporal treatment of organs at the TRIGA Mainz, the basic characteristics of the radiation field in the thermal column as beam geometry, neutron and gamma ray energies, angular distributions, neutron flux, as well as absorbed gamma and neutron doses must be determined in a reproducible way. To determine the mixed irradiation field thermoluminescence detectors (TLD) made of CaF(2):Tm with a newly developed energy-compensation filter system and LiF:Mg,Ti materials with different (6)Li concentrations and different thicknesses as well as thin gold foils were used. PMID:19380234

  8. Monte Carlo design for a new neutron collimator at the ENEA Casaccia TRIGA reactor.

    PubMed

    Burgio, N; Rosa, R

    2004-10-01

    The TRIGA RC-1 1MW reactor operating at ENEA Casaccia Center is currently being developed as a second neutron imaging facility that shall be devoted to computed tomography as well as neutron tomography. In order to reduce the gamma-ray content in the neutron beam, the reactor tangential piercing channel was selected. A set of Monte Carlo simulation was used to design the neutron collimator, to determine the preliminary choice of the materials to be employed in the collimator design. PMID:15246415

  9. Cryostat system for investigation on new neutron moderator materials at reactor TRIGA PUSPATI

    NASA Astrophysics Data System (ADS)

    Dris, Zakaria bin; Mohamed, Abdul Aziz bin; Hamid, Nasri A.; Azman, Azraf; Ahmad, Megat Harun Al Rashid Megat; Jamro, Rafhayudi; Yazid, Hafizal

    2016-01-01

    A simple continuous flow (SCF) cryostat was designed to investigate the neutron moderation of alumina in high temperature co-ceramic (HTCC) and polymeric materials such as Teflon under TRIGA neutron environment using a reflected neutron beam from a monochromator. Cooling of the cryostat will be carried out using liquid nitrogen. The cryostat will be built with an aluminum holder for moderator within stainless steel cylinder pipe. A copper thermocouple will be used as the temperature sensor to monitor the moderator temperature inside the cryostat holder. Initial measurements of neutron spectrum after neutron passing through the moderating materials have been carried out using a neutron spectrometer.

  10. Technical Specifications for the Neutron Radiography Facility (TRIGA Mark 1 Reactor). Revision 6

    SciTech Connect

    Tomlinson, R.L.; Perfect, J.F.

    1988-04-01

    These Technical Specifications state the limits under which the Neutron Radiography Facility, with its associated TRIGA Mark I Reactor, is operated by the Westinghouse Hanford Company for the US Department of Energy. These specifications cover operation of the Facility for the purpose of examination of specimens (including contained fissile material) by neutron radiography, for the irradiation of specimens in the pneumatic transfer system and approved in-core or in-pool irradiation facilities and operator training. The Final Safety Analysis Report (TC-344) and its supplements, and these Technical Specifications are the basic safety documents of the Neutron Radiography Facility.

  11. Unique applications of research reactors with TRIGA UZrH[sub x] fuel

    SciTech Connect

    Whittemore, W.L. )

    1993-01-01

    The TRIGA reactor fuel (UZrH[sub x]) in research reactors provides significant safety features that have permitted varied and unique applications. The safety features include a very large, prompt, negative temperature coefficient of reactivity; very high safety limit for fuel temperature (1150[degrees]C); and large fission product retention even for unclad fuel. The recognized safety of these reactors has permitted them to be located as appropriate on university campuses in buildings housing lecture halls and in hospitals. It has also facilitated installation of in-core or near-core experiments and facilities, including liquid hydrogen or other cryogenic neutron sources.

  12. Neutronics analysis of the proposed 25-MW leu TRIGA Multipurpose Research Reactor

    SciTech Connect

    Nurdin, M.; Bretscher, M.M.; Snelgrove, J.L.

    1982-01-01

    More than two years ago the government of Indonesia announced plans to purchase a research reactor for the Puspiptek Research Center in Serpong Indonesia to be used for isotope production, materials testing, neutron physics measurements, and reactor operator training. Reactors using low-enriched uranium (LEU) plate-type and rod-type fuel elements were considered. This paper deals with the neutronic evaluation of the rod-type 25-MW LEU TRIGA Multipurpose Research Reactor (MPRR) proposed by the General Atomic Company of the United States of America.

  13. 76 FR 69296 - University of Utah, University of Utah TRIGA Nuclear Reactor, Notice of Issuance of Renewed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... published in the Federal Register on July 21, 2011 (76 FR 43733-43737). The NRC received no request for a..., 2011 (76 FR 60091-60094), and concluded that renewal of the facility operating license will not have a... COMMISSION University of Utah, University of Utah TRIGA Nuclear Reactor, Notice of Issuance of...

  14. Assessment of Early Toxicity and Response in Patients Treated With Proton and Carbon Ion Therapy at the Heidelberg Ion Therapy Center Using the Raster Scanning Technique

    SciTech Connect

    Rieken, Stefan; Habermehl, Daniel; Nikoghosyan, Anna; Jensen, Alexandra; Haberer, Thomas; Jaekel, Oliver; Muenter, Marc W.; Welzel, Thomas; Debus, Juergen; Combs, Stephanie E.

    2011-12-01

    Puropose: To asses early toxicity and response in 118 patients treated with scanned ion beams to validate the safety of intensity-controlled raster scanning at the Heidelberg Ion Therapy Center. Patients and Methods: Between November 2009 and June 2010, we treated 118 patients with proton and carbon ion radiotherapy (RT) using active beam delivery. The main indications included skull base chordomas and chondrosarcomas, salivary gland tumors, and gliomas. We evaluated early toxicity within 6 weeks after RT and the initial clinical and radiologic response for quality assurance in our new facility. Results: In all 118 patients, few side effects were observed, in particular, no high numbers of severe acute toxicity were found. In general, the patients treated with particle therapy alone showed only a few single side effects, mainly Radiation Therapy Oncology Group/Common Terminology Criteria grade 1. The most frequent side effects and cumulative incidence of single side effects were observed in the head-and-neck patients treated with particle therapy as a boost and photon intensity-modulated RT. The toxicities included common radiation-attributed reactions known from photon RT, including mucositis, dysphagia, and skin erythema. The most predominant imaging responses were observed in patients with high-grade gliomas and those with salivary gland tumors. For skull base tumors, imaging showed a stable tumor outline in most patients. Thirteen patients showed improvement of pre-existing clinical symptoms. Conclusions: Side effects related to particle treatment were rare, and the overall tolerability of the treatment was shown. The initial response was promising. The data have confirmed the safe delivery of carbon ions and protons at the newly opened Heidelberg facility.

  15. Startup experience at the University of Texas TRIGA Mark II Reactor

    SciTech Connect

    Bauer, Thomas L.; Wehring, Bernard W.

    1992-07-01

    After eight years of singular effort, the UT-TRIGA Mark II research reactor was licensed and is fully operational. This reactor is the focus of a new reactor laboratory facility which is located at the Balcones Research Center, a north Austin campus of The University of Texas at Austin. The UT-TRIGA reactor is licensed for 1.1 MW steady power operation and 3 dollar pulsing. A startup program was implemented upon receipt of the facility license on January 17, 1992. Several facility features are unique to this startup. Among these were the use of fuel with various burnup and a digital control system. The reactor laboratory staff with assistance from a General Atomics instrumentation engineer performed all phases of the startup program. Core loading began in February 1992 with final testing completed in May 1992. Several unusual problems were encountered during this time. Experiment authorizations have been written to resume Neutron Activation Analysis programs and isotope production. Several neutron beam tube experiments are in the design and test phase. (author)

  16. Study of the effect of {sup 135}Xe poison on the temperature coefficient of TRIGA fuel

    SciTech Connect

    Iorgulis, Constantin

    1992-07-01

    A study of the influence of {sup 135}Xe on the prompt negative temperature coefficient of the 14-MW Romanian TRIGA reactor has been performed. Because of its large absorption cross section below 0.1 eV, we expected that {sup 135}Xe might make a positive contribution to the temperature coefficient because the higher-energy neutrons are less likely to be absorbed by the Xe. This effect would be largest about 16 hours after reactor shutdown. In order to investigate this phenomenon, we have performed cell and core calculations for various fuel temperatures, burnups, and {sup 135}Xe levels. These calculations indeed show a positive contribution of {sup 135}Xe to the temperature coefficient, especially for high burnups, where little {sup 167}Er remains to absorb the higher-energy neutrons. Work is in progress to evaluate the effect of the smaller negative temperature coefficient on the consequences of reactivity insertion accidents in unfavorable situations of {sup 135}Xe poisoning of the Romanian TRIGA core. (author)

  17. Radionuclide mass inventory, activity, decay heat, and dose rate parametric data for TRIGA spent nuclear fuels

    SciTech Connect

    Sterbentz, J.W.

    1997-03-01

    Parametric burnup calculations are performed to estimate radionuclide isotopic mass and activity concentrations for four different Training, Research, and Isotope General Atomics (TRIGA) nuclear reactor fuel element types: (1) Aluminum-clad standard, (2) Stainless Steel-clad standard, (3) High-enrichment Fuel Life Improvement Program (FLIP), and (4) Low-enrichment Fuel Life Improvement Program (FLIP-LEU-1). Parametric activity data are tabulated for 145 important radionuclides that can be used to generate gamma-ray emission source terms or provide mass quantity estimates as a function of decay time. Fuel element decay heats and dose rates are also presented parametrically as a function of burnup and decay time. Dose rates are given at the fuel element midplane for contact, 3.0-feet, and 3.0-meter detector locations in air. The data herein are estimates based on specially derived Beginning-of-Life (BOL) neutron cross sections using geometrically-explicit TRIGA reactor core models. The calculated parametric data should represent good estimates relative to actual values, although no experimental data were available for direct comparison and validation. However, because the cross sections were not updated as a function of burnup, the actinide concentrations may deviate from the actual values at the higher burnups.

  18. Fundamental approach to TRIGA steady-state thermal-hydraulic CHF analysis

    SciTech Connect

    Feldman, E.E.

    2008-07-15

    Methods are investigated for predicting the power at which critical heat flux (CHF) occurs in TRIGA reactors that rely on natural convection for primary flow. For a representative TRIGA reactor, two sets of functions are created. For the first set, the General Atomics STAT code and the more widely-used RELAP5-3D code are each employed to obtain reactor flow rate as a function of power. For the second set, the Bernath correlation, the 2006 Groeneveld table, the Hall and Mudawar outlet correlation, and each of the four PG-CHF correlations for rod bundles are used to predict the power at which CHF occurs as a function of channel flow rate. The two sets of functions are combined to yield predictions of the power at which CHF occurs in the reactor. A combination of the RELAP5-3D code and the 2006 Groeneveld table predicts 67% more CHF power than does a combination of the STAT code and the Bernath correlation. (author)

  19. Cross sections for fuel depletion and radioisotope production calculations in TRIGA reactors

    SciTech Connect

    Aguilar, H.F.; Mazon, R.R.

    1994-07-01

    For TRIGA Reactors, the fuel depletion and isotopic inventory calculations, depends on the computer code and in the cross sections of some important actinides used. Among these we have U-235, U-238, Pu-239, Pu-240 and Pu-241. We choose ORIGEN2, a code with a good reputation in this kind of calculations, we observed the cross sections for these actinides in the libraries that we have (PWR's and BWR), the fission cross section for U-235 was about 50 barns. We used a PWR library and our results were not satisfactory, specially for standard elements. We decided to calculate cross sections more suitable for our reactor, for that purpose we simulate the standard and FLIP TRIGA cells with the transport code WIMS. We used the fuel average flux and COLAPS (a home made program), to generate suitable cross sections for ORIGEN2, by collapsing the WIMS library cross sections of these nuclides. For the radioisotope production studies using the Central Thimble, we simulate the A and B rings and used the A average flux to collapse cross sections. For these studies, the required nuclides sometimes are not present in WIMS library, for them we are planning to process the ENDF/B data, with NJOY system, and include the cross sections to WIMS library or to collapse them using the appropriate average-flux and the program COLAPS. (author)

  20. Reduced enrichment neutronics evaluation for Texas A and M's TRIGA reactor

    SciTech Connect

    Rajalakshmi, M.J.; Reuscher, J.A. )

    1990-06-01

    The Texas A and M Nuclear Science Center reactor (NSCR) designed by General Atomics (GA) uses a fuel-life improvement program TRIGA fuel element. It is composed of 8.5 wt% uranium in U-ZrH{sub 1.6}-Er fuel with a {sup 235}U enrichment of 70 at.% and 1.5 wt% of erbium. The US Nuclear Regulatory Commission requires that the enrichment not exceed 20 at.% for the next loading, provided the fuel is available. To meet this requirement GA has developed shrouded four-rod clusters using low-enriched U-ZrH{sub 1.6}-Er fuel for TRIGA cores operating at powers up to 2 MW. This fuel contains 20 wt% of uranium with an enrichment of 20 at.% and 0.5 wt% of erbium and a homogeneous mixture of hydrogen moderator. Thermal-hydraulic calculations show the feasibility of operating the NSCR at 2 MW. The objective of this study is to assess the ability of the NSCR to operate at 2 MW using the reduced-enrichment fuel. This study also covers a three-dimensional neutronics analysis of the NSCR core using the new fuel. Results obtained are compared with results obtained with another candidate fuel, BeO-UO{sub 2}-Er.

  1. Electron versus proton accelerator driven sub-critical system performance using TRIGA reactors at power

    SciTech Connect

    Carta, M.; Burgio, N.; D'Angelo, A.; Santagata, A.; Petrovich, C.; Schikorr, M.; Beller, D.; Felice, L. S.; Imel, G.; Salvatores, M.

    2006-07-01

    This paper provides a comparison of the performance of an electron accelerator-driven experiment, under discussion within the Reactor Accelerator Coupling Experiments (RACE) Project, being conducted within the U.S. Dept. of Energy's Advanced Fuel Cycle Initiative (AFCI), and of the proton-driven experiment TRADE (TRIGA Accelerator Driven Experiment) originally planned at ENEA-Casaccia in Italy. Both experiments foresee the coupling to sub-critical TRIGA core configurations, and are aimed to investigate the relevant kinetic and dynamic accelerator-driven systems (ADS) core behavior characteristics in the presence of thermal reactivity feedback effects. TRADE was based on the coupling of an upgraded proton cyclotron, producing neutrons via spallation reactions on a tantalum (Ta) target, with the core driven at a maximum power around 200 kW. RACE is based on the coupling of an Electron Linac accelerator, producing neutrons via photoneutron reactions on a tungsten-copper (W-Cu) or uranium (U) target, with the core driven at a maximum power around 50 kW. The paper is focused on analysis of expected dynamic power response of the RACE core following reactivity and/or source transients. TRADE and RACE target-core power coupling coefficients are compared and discussed. (authors)

  2. University of Illinois nuclear pumped laser program. [experiments with a TRIGA pulsed reactor with a broad pulse and a low peak flux

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1979-01-01

    The development of nuclear pumped lasers with improved efficiency, energy storage capability, and UF6 volume pumping is reviewed. Results of nuclear pumped laser experiments using a TRIGA-type pulsed reactor are outlined.

  3. Relative fission product yield determination in the USGS TRIGA Mark I reactor

    NASA Astrophysics Data System (ADS)

    Koehl, Michael A.

    Fission product yield data sets are one of the most important and fundamental compilations of basic information in the nuclear industry. This data has a wide range of applications which include nuclear fuel burnup and nonproliferation safeguards. Relative fission yields constitute a major fraction of the reported yield data and reduce the number of required absolute measurements. Radiochemical separations of fission products reduce interferences, facilitate the measurement of low level radionuclides, and are instrumental in the analysis of low-yielding symmetrical fission products. It is especially useful in the measurement of the valley nuclides and those on the extreme wings of the mass yield curve, including lanthanides, where absolute yields have high errors. This overall project was conducted in three stages: characterization of the neutron flux in irradiation positions within the U.S. Geological Survey TRIGA Mark I Reactor (GSTR), determining the mass attenuation coefficients of precipitates used in radiochemical separations, and measuring the relative fission products in the GSTR. Using the Westcott convention, the Westcott flux, modified spectral index, neutron temperature, and gold-based cadmium ratios were determined for various sampling positions in the USGS TRIGA Mark I reactor. The differential neutron energy spectrum measurement was obtained using the computer iterative code SAND-II-SNL. The mass attenuation coefficients for molecular precipitates were determined through experiment and compared to results using the EGS5 Monte Carlo computer code. Difficulties associated with sufficient production of fission product isotopes in research reactors limits the ability to complete a direct, experimental assessment of mass attenuation coefficients for these isotopes. Experimental attenuation coefficients of radioisotopes produced through neutron activation agree well with the EGS5 calculated results. This suggests mass attenuation coefficients of molecular

  4. Long-term observations of 14C-based atmospheric fossil fuel CO2 (FFCO2) and the CO/FFCO2 ratio in the Heidelberg urban environment

    NASA Astrophysics Data System (ADS)

    Levin, Ingeborg; Hammer, Samuel; Kromer, Bernd

    2013-04-01

    Urban environments are large emitters of fossil fuel CO2 and of combustion-related pollutants, such as carbon monoxide (CO). While huge efforts are currently undertaken to agree on commitments to reduce fossil fuel CO2 emissions, these have not really been successful yet, and the global atmospheric CO2 abundance is still increasing. However, the implementation of emission controls on pollutants, e.g. from traffic, seem to have been more efficient, based on recent emission inventory data (e.g. http://www.statistik.baden-wuerttemberg.de). In order to verify this bottom-up information we present here ten years of quasi-continuous atmospheric observations of CO2, fossil fuel CO2 (FFCO2) and CO in Heidelberg. The fossil fuel CO2 component is determined from integrated radiocarbon (14CO2) measurements, exploiting the fact that fossil fuel CO2 lacks 14C (e.g. Levin et al., Geophys. Res. Lett. 30, 2003). Our measurements show that the fossil fuel CO2 level in the Heidelberg suburbs has not significantly changed (i.e. decreased) in the last decade. Observed inter-annual variations are rather due to inter-annual changes of atmospheric transport, as was already reported by Levin and Rödenbeck (Naturwissenschaften 95, 2008). However, we find a ca. 25% change in the CO/FFCO2 ratio of the regional concentration offsets compared to background levels from about 14.5 ppb/ppm in 2002 to about 11 ppb/ppm in 2009. This observation is in very good agreement with the emission statistic for the closer catchment area of our measurement site. The Statistische Landesamt, Baden-Württemberg (http://www.statistik.baden-wuerttemberg.de) reported a change in the CO to FFCO2 emission ratio for the city area of Heidelberg from 13.8 ppb/ppm in 2000 to 10.5 ppb/ppm in 2007. A more than 20% decrease of the CO/FFCO2 emission ratio is also reported for the whole state of Baden-Württemberg (south-west Germany), but note that these ratios are generally smaller, between 11.5 and 9 ppb/ppm, due to a

  5. The characteristic assessment of spent ion exchange resin from PUSPATI TRIGA REACTOR (RTP) for immobilization process

    SciTech Connect

    Wahida, Nurul; Yasir, Muhamad Samudi; Majid, Amran Ab; Irwan, M. N.; Wahab, Mohd Abd; Marzukee, Nik; Paulus, Wilfred; Phillip, Esther; Thanaletchumy

    2014-09-03

    In this paper, spent ion exchange resin generated from PUSPATI TRIGA reactor (RTP) in Malaysian Nuclear Agency were characterized based on the water content, radionuclide content and radionuclide leachability. The result revealed that the water content in the spent resin is 48%. Gamma spectrometry analysis indicated the presence of {sup 134}Cs, {sup 137}Cs, {sup 152}Eu, {sup 54}Mn, {sup 58}Co, {sup 60}Co and {sup 65}Zn. The leachability test shows a small concentrations (<1 Bq/l) of {sup 152}Eu and {sup 134}Cs were leached out from the spent resin while {sup 60}Co activity concentrations slightly exceeded the limit generally used for industrial wastewater i.e. 1 Bq/l. Characterization of spent ion exchange resin sampled from RTP show that this characterization is important as a basis to immobilize this radioactive waste using geopolymer technology.

  6. Simulation on reactor TRIGA Puspati core kinetics fueled with thorium (Th) based fuel element

    NASA Astrophysics Data System (ADS)

    Mohammed, Abdul Aziz; Pauzi, Anas Muhamad; Rahman, Shaik Mohmmed Haikhal Abdul; Zin, Muhamad Rawi Muhammad; Jamro, Rafhayudi; Idris, Faridah Mohamad

    2016-01-01

    In confronting global energy requirement and the search for better technologies, there is a real case for widening the range of potential variations in the design of nuclear power plants. Smaller and simpler reactors are attractive, provided they can meet safety and security standards and non-proliferation issues. On fuel cycle aspect, thorium fuel cycles produce much less plutonium and other radioactive transuranic elements than uranium fuel cycles. Although not fissile itself, Th-232 will absorb slow neutrons to produce uranium-233 (233U), which is fissile. By introducing Thorium, the numbers of highly enriched uranium fuel element can be reduced while maintaining the core neutronic performance. This paper describes the core kinetic of a small research reactor core like TRIGA fueled with a Th filled fuel element matrix using a general purpose Monte Carlo N-Particle (MCNP) code.

  7. Operation and reactivity measurements of an accelerator driven subcritical TRIGA reactor

    NASA Astrophysics Data System (ADS)

    O'Kelly, David Sean

    Experiments were performed at the Nuclear Engineering Teaching Laboratory (NETL) in 2005 and 2006 in which a 20 MeV linear electron accelerator operating as a photoneutron source was coupled to the TRIGA (Training, Research, Isotope production, General Atomics) Mark II research reactor at the University of Texas at Austin (UT) to simulate the operation and characteristics of a full-scale accelerator driven subcritical system (ADSS). The experimental program provided a relatively low-cost substitute for the higher power and complexity of internationally proposed systems utilizing proton accelerators and spallation neutron sources for an advanced ADSS that may be used for the burning of high-level radioactive waste. Various instrumentation methods that permitted ADSS neutron flux monitoring in high gamma radiation fields were successfully explored and the data was used to evaluate the Stochastic Pulsed Feynman method for reactivity monitoring.

  8. Verification of MCNP simulation of neutron flux parameters at TRIGA MK II reactor of Malaysia.

    PubMed

    Yavar, A R; Khalafi, H; Kasesaz, Y; Sarmani, S; Yahaya, R; Wood, A K; Khoo, K S

    2012-10-01

    A 3-D model for 1 MW TRIGA Mark II research reactor was simulated. Neutron flux parameters were calculated using MCNP-4C code and were compared with experimental results obtained by k(0)-INAA and absolute method. The average values of φ(th),φ(epi), and φ(fast) by MCNP code were (2.19±0.03)×10(12) cm(-2)s(-1), (1.26±0.02)×10(11) cm(-2)s(-1) and (3.33±0.02)×10(10) cm(-2)s(-1), respectively. These average values were consistent with the experimental results obtained by k(0)-INAA. The findings show a good agreement between MCNP code results and experimental results. PMID:22885391

  9. Irradiation facility at the TRIGA Mainz for treatment of liver metastases.

    PubMed

    Hampel, G; Wortmann, B; Blaickner, M; Knorr, J; Kratz, J V; Lizón Aguilar, A; Minouchehr, S; Nagels, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L

    2009-07-01

    The TRIGA Mark II reactor at the University of Mainz provides ideal conditions for duplicating BNCT treatment as performed in Pavia, Italy, in 2001 and 2003 [Pinelli, T., Zonta, A., Altieri, S., Barni, S., Braghieri, A., Pedroni, P., Bruschi, P., Chiari, P., Ferrari, C., Fossati, F., Nano, R., Ngnitejeu Tata, S., Prati, U., Ricevuti, G., Roveda, L., Zonta, C., 2002. TAOrMINA: from the first idea to the application to the human liver. In: Sauerwein et al. (Eds.), Research and Development in Neutron Capture Therapy. Proceedings of the 10th International Congress on Neutron Capture Therapy, Monduzzi editore, Bologna, pp. 1065-1072]. In order to determine the optimal parameters for the planned therapy and therefore for the design of the thermal column, calculations were conducted using the MCNP-code and the transport code ATTILA. The results of the parameter study as well as a possible configuration for the irradiation of the liver are presented. PMID:19394836

  10. Accuracy studies with carbon clusters at the Penning trap mass spectrometer TRIGA-TRAP

    NASA Astrophysics Data System (ADS)

    Ketelaer, J.; Beyer, T.; Blaum, K.; Block, M.; Eberhardt, K.; Eibach, M.; Herfurth, F.; Smorra, C.; Nagy, Sz.

    2010-05-01

    Extensive cross-reference measurements of well-known frequency ratios using various sizes of carbon cluster ions 12Cn + (10≤n≤23) were performed to determine the effects limiting the accuracy of mass measurements at the Penning-trap facility TRIGA-TRAP. Two major contributions to the uncertainty of a mass measurement have been identified. Fluctuations of the magnetic field cause an uncertainty in the frequency ratio due to the required calibration by a reference ion of uf(νref)/νref = 6(2) × 10-11/min × Δt. A mass-dependent systematic shift of the frequency ratio of epsilonm(r)/r = -2.2(2) × 10-9 × (m-mref)/u has been found as well. Finally, the nuclide 197Au was used as a cross-check since its mass is already known with an uncertainty of 0.6 keV.

  11. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry.

    PubMed

    Wang, T K; Peir, J J

    2000-01-01

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products 97Zr/97Nb, 132I, and 140La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by reirradiating the spent fuels in a nuclear reactor. Based on the measured activities, 235U burn-up values can be deduced by iterative calculations. The complication caused by 239Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products 137Cs, 134Cs/137Cs ratio and 106Ru/137Cs ratio. PMID:10670930

  12. Determination of α and f parameters at the 14-MW TRIGA reactor at Pitesti, Romania

    NASA Astrophysics Data System (ADS)

    Bărbos, D.; Păunoiu, C.; Roth, C.

    2010-10-01

    For experimental α determination the two-monitor method has been applied to determine α parameter in the irradiation channels at TRIGA 14 MW reactor (SCN Pitesti). The modified two-monitor method by using Cd ratio measurements eliminates the introducing of systematic errors due to the inaccuracy of absolute nuclear data. This characterization of the epithermal neutron spectrum is used in the k0-method of NAA, implemented at the SCN Pitesti. Neutron spectrum parameters were determined in the inner irradiation channel XC-1 and for outer irradiation channels: Beryllium J-6, Beryllium J-7, and Beryllium K-11. For α and f parameter verification a standard reference material denominated ECRM379-1 was analyzed using k0 standardization.

  13. Neutron spectra at two beam ports of a TRIGA Mark III reactor loaded with HEU fuel.

    PubMed

    Vega-Carrillo, H R; Hernández-Dávila, V M; Aguilar, F; Paredes, L; Rivera, T

    2014-01-01

    The neutron spectra have been measured in two beam ports, one radial and another tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research in Mexico. Measurements were carried out with the reactor core loaded with high enriched uranium fuel. Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a (6)LiI(Eu) scintillator and 2, 3, 5, 8, 10 and 12 in.-diameter high-density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code. For each spectrum total flux, mean energy and ambient dose equivalent were determined. Measured spectra show fission, epithermal and thermal neutrons, being harder in the radial beam port. PMID:23746708

  14. Final qualification testing results for TRIGA low-enriched uranium fuel

    SciTech Connect

    West, G.B.; Simnad, M.T.; Copeland, G.L.

    1987-01-01

    Following the adoption of policies by the US government and other fuel supplier nations to limit, with few exceptions, export of fuels to those enriched to < 20% in /sup 235/U, GA Technologies undertook, starting in 1976, a rigorous program to develop uranium zirconium-hydride fuels with high uranium concentrations up to 3.7 g U/cm/sup 3/, while limiting the enrichment to < 20% in /sup 235/U. By increasing the uranium concentration from 8.5 to 45 wt% and by including erbium as a burnable poison, the long reactivity lifetime of the high-enriched uranium cores has been preserved. The achieved purpose of these low-enriched uranium (LEU) fuels was also to preserve all the unique safety features of the TRIGA fuel system - prompt negative temperature coefficient of reactivity, high fission product retentivity, chemical stability when quenched from high temperatures in water, and dimensional stability over a broad range of operating temperatures.

  15. Thermal hydraulic analysis for the Oregon State TRIGA reactor using RELAP5-3D

    SciTech Connect

    Marcum, W.R.; Woods, B.G.; Hartman, M.

    2008-07-15

    Thermal hydraulic analyses have being conducted at Oregon State University (OSU) in support of the conversion of the OSU TRIGA reactor (OSTR) core from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel as part of the Reduced Enrichment for Research and Test Reactors program. The goals of the thermal hydraulic analyses were to calculate natural circulation flow rates, coolant temperatures and fuel temperatures as a function of core power for both the HEU and LEU cores; calculate peak values of fuel temperature, cladding temperature, surface heat flux as well as departure from nuclear boiling ratio (DNBR) for steady state and pulse operation; and perform accident analyses for the accident scenarios identified in the OSTR safety analysis report. RELAP5-3D Version 2.4.2 was implemented to develop a model for the thermal hydraulic study. The OSTR core conversion is planned to take place in late 2008. (author)

  16. Development process of the new control console of ININ's TRIGA mark III reactor

    SciTech Connect

    Rivero-Gutierrez, T.

    2006-07-01

    A description of the development of the new ININ's TRIGA Mark III reactor control console is presented in this meeting. Most of the operation and safety monitoring of the reactor is carried out by means of a personal computer (PC), some interface cards, and an auxiliary computer that drives the control rod mechanisms. In this console, the safety actions are taken by the Protection System (SEC), which acquires the data directly from the safety related systems, specified in the reactor's console design technical specifications. The console, based on the concept of virtual instrumentation, is composed of a group of systems that make easier to the operator the activation of the sequential steps required to operate the reactor. (authors)

  17. Core Calculation of 1 MWatt PUSPATI TRIGA Reactor (RTP) using Monte Carlo MVP Code System

    SciTech Connect

    Karim, Julia Abdul

    2008-05-20

    The Monte Carlo MVP code system was adopted for the Reaktor TRIGA PUSAPTI (RTP) core calculation. The code was developed by a group of researcher of Japan Atomic Energy Agency (JAEA) first in 1994. MVP is a general multi-purpose Monte Carlo code for neutron and photon transport calculation and able to estimate an accurate simulation problems. The code calculation is based on the continuous energy method. This code is capable of adopting an accurate physics model, geometry description and variance reduction technique faster than conventional method as compared to the conventional scalar method. This code could achieve higher computational speed by several factors on the vector super-computer. In this calculation, RTP core was modeled as close as possible to the real core and results of keff flux, fission densities and others were obtained.

  18. The characteristic assessment of spent ion exchange resin from PUSPATI TRIGA REACTOR (RTP) for immobilization process

    NASA Astrophysics Data System (ADS)

    Wahida, Nurul; Yasir, Muhamad Samudi; Majid, Amran Ab; Wahab, Mohd Abd; Marzukee, Nik; Paulus, Wilfred; Phillip, Esther; Thanaletchumy, Irwan, M. N.

    2014-09-01

    In this paper, spent ion exchange resin generated from PUSPATI TRIGA reactor (RTP) in Malaysian Nuclear Agency were characterized based on the water content, radionuclide content and radionuclide leachability. The result revealed that the water content in the spent resin is 48%. Gamma spectrometry analysis indicated the presence of 134Cs, 137Cs, 152Eu, 54Mn, 58Co, 60Co and 65Zn. The leachability test shows a small concentrations (<1 Bq/l) of 152Eu and 134Cs were leached out from the spent resin while 60Co activity concentrations slightly exceeded the limit generally used for industrial wastewater i.e. 1 Bq/l. Characterization of spent ion exchange resin sampled from RTP show that this characterization is important as a basis to immobilize this radioactive waste using geopolymer technology.

  19. Criticality safety assessment of a TRIGA reactor spent-fuel pool under accident conditions

    SciTech Connect

    Glumac, B; Ravnik, M.; Logar, M.

    1997-02-01

    Additional criticality safety analysis of a pool-type storage for TRIGA spent fuel at the Jozef Stefan Institute in Ljubljana, Slovenia, is presented. Previous results have shown that subcriticality is not guaranteed for some postulated accidents (earthquake with subsequent fuel rack disintegration resulting in contact fuel pitch) under the assumption that the fuel rack is loaded with fresh 12 wt% standard fuel. To mitigate this deficiency, a study was done on replacing a certain number of fuel elements in the rack with cadmium-loaded absorber rods. The Monte Carlo computer code MCNP4A with an ENDF/B-V library and detailed three-dimensional geometrical model of the spent-fuel rack was used for this purpose. First, a minimum critical number of fuel elements was determined for contact pitch, and two possible geometries of rack disintegration were considered. Next, it was shown that subcriticality can be ensured when pitch is decreased from a rack design pitch of 8 cm to contact, if a certain number of fuel elements (8 to 20 out of 70) are replaced by absorber rods, which are uniformly mixed into the lattice. To account for the possibility that random mixing of fuel elements and absorber rods can occur during rack disintegration and result in a supercritical configuration, a probabilistic study was made to sample the probability density functions for random absorber rod lattice loadings. Results of the calculations show that reasonably low probabilities for supercriticality can be achieved (down to 10{sup {minus}6} per severe earthquake, which would result in rack disintegration and subsequent maximum possible pitch decrease) even in the case where fresh 12 wt% standard TRIGA fuel would be stored in the spent-fuel pool.

  20. McClellan Nuclear Radiation Center (MNRC) TRIGA reactor: Four years of operations

    SciTech Connect

    Heidel, C.C.; Richards, W.J.

    1994-07-01

    McClellan Air Force Base, at Sacramento, California, is headquarters for the Sacramento Air Force Logistics Center (SM-ALC). McClellan Air Force Base provides extensive inspection and maintenance capabilities for the F-111, F-1 5, and other military aircraft. Criticality of the MNRC TRIGA reactor was obtained on January 20, 1990 with 63 standard TRIGA fuel elements, three fuel-followed control rods and one air-followed control rod. Presently there are 93 fuel elements in the reactor core. The reactor can be operated at 1 MW steady state power, producing pulses up to three dollars worth of reactivity addition, and can be square waved up to 1 MW. The reactor core contains a circular grid plate and a graphite reflector assembly surrounding the core. Four tangential beam ports installed in the reflector assembly provide a thermal neutron flux to four radiography bays. The reactor tank is twenty-four (24) feet deep, seven and one-half (7.5) feet in diameter, and has a protrusion in the upper portion of the reactor tank. This protrusion is scheduled for use as a neutron thermal collimator in the future. Besides the neutron radiography capabilities, the reactor contains a pneumatic rabbit system, a central thimble, an in-core irradiation facility, and three additional cutouts that provide locations for additional irradiation facilities. The central thimble can be removed along with the B-ring locations of the upper portion of the grid plate to provide an additional and larger in-core irradiation facility. A new upper grid plate has been manufactured to expand one triangular cutout so that larger experiments can be inserted directly into the reactor core. Some operational problems experienced during the first four years of operations are the timeout of the CSC and DAC watchdogs, deterioration of the heat exchanger gaskets, and loss of thermocouples in the instrumented fuel elements. (author)

  1. Neutronic and thermal hydraulic analysis of the Geological Survey TRIGA Reactor

    NASA Astrophysics Data System (ADS)

    Shugart, Nicolas

    The United States Geological Survey TRIGA Reactor (GSTR) is a 1 MW reactor located in Lakewood, Colorado. In support of the GSTR's relicensing efforts, this project developed and validated a Monte Carlo N-Particle Version 5 (MCNP5) model of the GSTR reactor. The model provided estimates of the excess reactivity, power distribution and the fuel temperature, water temperature, void, and power reactivity coefficients for the current and limiting core. The MCNP5 model predicts a limiting core excess reactivity of 6.48 with a peak rod power of 22.2 kW. The fuel and void reactivity coefficients for the limiting core are strongly negative, and the core water reactivity coefficient is slightly positive, consistent with other TRIGA analyses. The average fuel temperature reactivity coefficient of the full power limiting core is -0.0135 /K while the average core void coefficient is -0.069 /K from 0-20 % void. The core water temperature reactivity coefficient is +0.012 /K. Following the neutronics analysis, the project developed RELAP5 and PARET-ANL models of the GSTR hot-rod fuel channel under steady state and transient conditions. The GSTR limiting core, determined as part of this analysis, provides a worst case operating scenario for the reactor. During steady state operations, the hot rod of the limiting core has a peak fuel temperature of 829 K and a minimum departure from nucleate boiling ratio of 2.16. After a $3.00 pulse reactivity insertion the fuel reaches a peak temperature is 1070 K. Examining the model results several seconds after a pulse reveals flow instabilities that result from weaknesses in the current two-channel model.

  2. First measurements of continuous δ18O-CO2 with a Fourier Transform InfraRed spectrometer in Heidelberg, Germany

    NASA Astrophysics Data System (ADS)

    Vardag, Sanam Noreen; Hammer, Samuel; Griffith, David; Levin, Ingeborg

    2014-05-01

    Continuous in-situ measurements of δ13C and δ18O in atmospheric CO2 open the door to differentiating between different CO2 source and sink components with high temporal resolution. Until now only few instruments have been able to provide a continuous measurement of the oxygen isotope ratio in CO2. The Fourier Transform InfraRed (FTIR) spectrometer measures both the 13C/12C and 18O/16O ratios of CO2, but the precision and accuracy of the δ18O-CO2 measurements have not yet been evaluated. Here we present a first analysis of δ18O-CO2 measurements with an FTIR trace gas and isotope analyser in Heidelberg. We find that the spectrometer resolves 18O in CO2 with a reproducibility of better than δ18O= ± 0.3 o as determined from target gas measurements over a period of ten months. An Allan variance test shows that the δ18O repeatability reaches 0.1 o for hourly means. The compatibility of the spectroscopic measurements was determined by comparing FTIR measurements of δ18O of ambient air to the mass-spectrometric measurements on flask samples episodically collected over two diurnal cycles (events). A compatibility of better than ± 0.1 o for δ18O was found during these comparisons. Even though the FTIR precision does not reach that of isotope ratio mass spectrometry, a number of interesting scientific applications seem possible. In particular, investigation of processes that govern the δ18O variability of atmospheric CO2 on the regional scale seem very promising. Two episodes of recent ambient air measurements in Heidelberg, one in winter and one in summer, illustrate how high resolution regional δ18O and δ13C records may provide a better understanding of the regional scale processes leading atmospheric CO2 variability. However, quantitative analysis requires comprehensive knowledge on the isotopic signature of different CO2 sources and sinks as well as the influencing water reservoirs, which may largely govern the δ18O-CO2 variability during summer.

  3. Palliative chemotherapy for gastroesophageal cancer in old and very old patients: A retrospective cohort study at the National Center for Tumor Diseases, Heidelberg

    PubMed Central

    Berger, Anne Katrin; Zschaebitz, Stefanie; Komander, Christine; Jäger, Dirk; Haag, Georg Martin

    2015-01-01

    AIM: To investigate the outcome of palliative chemotherapy in old patients with gastroesophageal cancer at the National Center for Tumor Diseases, Heidelberg. METHODS: Using a prospectively generated database, we retrospectively analyzed 55 patients ≥ 70 years under palliative chemotherapy for advanced gastroesophageal cancer at the outpatient clinic of the National Center for Tumor Diseases Heidelberg, Germany between January 2006 and December 2013. Further requirements for inclusion were (1) histologically proven diagnosis of gastroesophageal cancer; (2) advanced (metastatic or inoperable) disease; and (3) no history of radiation or radiochemotherapy. The clinical information included Eastern Cooperative Oncology Group performance status (ECOG PS), presence and site of metastases at diagnosis, date of previous surgery and perioperative chemotherapy, start and stop date of first-line treatment, toxicities and consecutive dosage reductions of first-line treatment, response to first-line therapy, date of progression, usage of second-line therapies and date and cause of death. Survival times [progression-free survival (PFS), overall survival (OS) and residual survival (RS)] were calculated. Toxicity and safety were examined. Prognostic factors including ECOG PS, age and previous perioperative treatment were analyzed. RESULTS: Median age of our cohort was 76 years. 86% of patients received a combination of two cytotoxic drugs. 76 percent of patients had an oxaliplatin-based first-line therapy with the oxaliplatin and 5-fluorouracil regimen being the predominantely chosen regimen (69%). Drug modifications due to toxicity were necessary in 56% of patients, and 11% of patients stopped treatment due to toxicities. Survival times of our cohort are in good accordance with the major phase III trials that included mostly younger patients: PFS and OS were 5.8 and 9.5 mo, respectively. Survival differed significantly between patient groups with low (≤ 1) and high (≥ 2

  4. Validation of the neutron and gamma fields in the JSI TRIGA reactor using in-core fission and ionization chambers.

    PubMed

    Žerovnik, Gašper; Kaiba, Tanja; Radulović, Vladimir; Jazbec, Anže; Rupnik, Sebastjan; Barbot, Loïc; Fourmentel, Damien; Snoj, Luka

    2015-02-01

    CEA developed fission chambers and ionization chambers were utilized at the JSI TRIGA reactor to measure neutron and gamma fields. The measured axial fission rate distributions in the reactor core are generally in good agreement with the calculated values using the Monte Carlo model of the reactor thus verifying both the computational model and the fission chambers. In future, multiple absolutely calibrated fission chambers could be used for more accurate online reactor thermal power monitoring. PMID:25479432

  5. The Heidelberg Airborne Imaging DOAS Instrument (HAIDI) - a novel Imaging DOAS device for 2-D and 3-D imaging of trace gases and aerosols

    NASA Astrophysics Data System (ADS)

    General, S.; Pöhler, D.; Sihler, H.; Bobrowski, N.; Frieß, U.; Zielcke, J.; Horbanski, M.; Shepson, P. B.; Stirm, B. H.; Simpson, W. R.; Weber, K.; Fischer, C.; Platt, U.

    2014-03-01

    Many relevant processes in tropospheric chemistry take place on rather small scales (e.g. tens to hundreds of meters) but often influence areas of several square kilometer. Thus, measurements of the involved trace gases with high spatial resolution are of great scientific interest. In order to identify individual sources and sinks and ultimately to improve chemical transport models, we developed a new airborne instrument, which is based on the well established DOAS method. The Heidelberg Airborne Imaging Differential Optical Absorption Spectrometer Instrument (HAIDI) is a passive imaging DOAS spectrometer, which is capable of recording horizontal and vertical trace gas distributions with a resolution of better than 100 m. Observable species include NO2, HCHO, C2H2O2, H2O, O3, O4, SO2, IO, OClO and BrO. Here we report a technical description of the instrument including its custom build spectrographs and CCD detectors. Also first results from measurements with the new instrument are presented. These comprise spatial resolved SO2 and BrO in volcanic plumes, mapped at Mt. Etna (Sicily, Italy), NO2 emissions in the metropolitan area of Indianapolis (Indiana, USA) as well as BrO and NO2 distributions measured during arctic springtime in context of the BROMEX campaign, which was performed 2012 in Barrow (Alaska, USA).

  6. The Heidelberg Airborne Imaging DOAS Instrument (HAIDI) - a novel imaging DOAS device for 2-D and 3-D imaging of trace gases and aerosols

    NASA Astrophysics Data System (ADS)

    General, S.; Pöhler, D.; Sihler, H.; Bobrowski, N.; Frieß, U.; Zielcke, J.; Horbanski, M.; Shepson, P. B.; Stirm, B. H.; Simpson, W. R.; Weber, K.; Fischer, C.; Platt, U.

    2014-10-01

    Many relevant processes in tropospheric chemistry take place on rather small scales (e.g., tens to hundreds of meters) but often influence areas of several square kilometer. Thus, measurements of the involved trace gases with high spatial resolution are of great scientific interest. In order to identify individual sources and sinks and ultimately to improve chemical transport models, we developed a new airborne instrument, which is based on the well established Differential Optical Absorption Spectroscopy (DOAS) method. The Heidelberg Airborne Imaging DOAS Instrument (HAIDI) is a passive imaging DOAS spectrometer, which is capable of recording horizontal and vertical trace gas distributions with a resolution of better than 100 m. Observable species include NO2, HCHO, C2H2O2, H2O, O3, O4, SO2, IO, OClO and BrO. Here we give a technical description of the instrument including its custom-built spectrographs and CCD detectors. Also first results from measurements with the new instrument are presented. These comprise spatial resolved SO2 and BrO in volcanic plumes, mapped at Mt. Etna (Sicily, Italy), NO2 emissions in the metropolitan area of Indianapolis (Indiana, USA) as well as BrO and NO2 distributions measured during arctic springtime in context of the BRomine, Ozone, and Mercury EXperiment (BROMEX) campaign, which was performed 2012 in Barrow (Alaska, USA).

  7. Centrosome and spindle pole body dynamics. Review and abstracts of the EMBO/EMBL Conference on Centrosomes and Spindle Pole Bodies, Heidelberg, September 13-17, 2002.

    PubMed

    2003-02-01

    Five years after the first meeting held on Centrosomes and Spindle Pole Bodies, a second meeting was organized by Tano Gonzalez, Eric Karsenti, Kip Sluder, and Mark Winey in Heidelberg, Germany. Sponsored by the gracious European community (EMBO/EMBL), the meeting was both spectacular and exhausting. The wealth of information delivered, the plethora of model systems and unique approaches described, and the free exchange of information by a cooperative and excited community of scientists overwhelmed all participants. Even the best prepared scholars could not have anticipated the avalanche of data and insights that poured from the presentations from beginning to end. Daily posters by young and senior scientists added dimension to round out the well-planned series of presentations. The meeting began with opening remarks by Eric Karsenti and Michel Bornens who reminded participants of the historical questions of the field. Where does the centrosome come from? What are the mechanisms that control centrosome assembly and duplication? How is duplication coordinated with the cell cycle? Why do some cells have centrosomes, while others do not? What are the components of the centrosome? Does the centrosome play an important role in disease? PMID:12529860

  8. Heidelberg-mCT-Analyzer: a novel method for standardized microcomputed-tomography-guided evaluation of scaffold properties in bone and tissue research.

    PubMed

    Westhauser, Fabian; Weis, Christian; Hoellig, Melanie; Swing, Tyler; Schmidmaier, Gerhard; Weber, Marc-André; Stiller, Wolfram; Kauczor, Hans-Ulrich; Moghaddam, Arash

    2015-11-01

    Bone tissue engineering and bone scaffold development represent two challenging fields in orthopaedic research. Micro-computed tomography (mCT) allows non-invasive measurement of these scaffolds' properties in vivo. However, the lack of standardized mCT analysis protocols and, therefore, the protocols' user-dependency make interpretation of the reported results difficult. To overcome these issues in scaffold research, we introduce the Heidelberg-mCT-Analyzer. For evaluation of our technique, we built 10 bone-inducing scaffolds, which underwent mCT acquisition before ectopic implantation (T0) in mice, and at explantation eight weeks thereafter (T1). The scaffolds' three-dimensional reconstructions were automatically segmented using fuzzy clustering with fully automatic level-setting. The scaffold itself and its pores were then evaluated for T0 and T1. Analysing the scaffolds' characteristic parameter set with our quantification method showed bone formation over time. We were able to demonstrate that our algorithm obtained the same results for basic scaffold parameters (e.g. scaffold volume, pore number and pore volume) as other established analysis methods. Furthermore, our algorithm was able to analyse more complex parameters, such as pore size range, tissue mineral density and scaffold surface. Our imaging and post-processing strategy enables standardized and user-independent analysis of scaffold properties, and therefore is able to improve the quantitative evaluations of scaffold-associated bone tissue-engineering projects. PMID:26716008

  9. Heidelberg-mCT-Analyzer: a novel method for standardized microcomputed-tomography-guided evaluation of scaffold properties in bone and tissue research

    PubMed Central

    Weis, Christian; Hoellig, Melanie; Swing, Tyler; Schmidmaier, Gerhard; Weber, Marc-André; Stiller, Wolfram; Kauczor, Hans-Ulrich; Moghaddam, Arash

    2015-01-01

    Bone tissue engineering and bone scaffold development represent two challenging fields in orthopaedic research. Micro-computed tomography (mCT) allows non-invasive measurement of these scaffolds’ properties in vivo. However, the lack of standardized mCT analysis protocols and, therefore, the protocols’ user-dependency make interpretation of the reported results difficult. To overcome these issues in scaffold research, we introduce the Heidelberg-mCT-Analyzer. For evaluation of our technique, we built 10 bone-inducing scaffolds, which underwent mCT acquisition before ectopic implantation (T0) in mice, and at explantation eight weeks thereafter (T1). The scaffolds’ three-dimensional reconstructions were automatically segmented using fuzzy clustering with fully automatic level-setting. The scaffold itself and its pores were then evaluated for T0 and T1. Analysing the scaffolds’ characteristic parameter set with our quantification method showed bone formation over time. We were able to demonstrate that our algorithm obtained the same results for basic scaffold parameters (e.g. scaffold volume, pore number and pore volume) as other established analysis methods. Furthermore, our algorithm was able to analyse more complex parameters, such as pore size range, tissue mineral density and scaffold surface. Our imaging and post-processing strategy enables standardized and user-independent analysis of scaffold properties, and therefore is able to improve the quantitative evaluations of scaffold-associated bone tissue-engineering projects. PMID:26716008

  10. The Effect of Pitch, Burnup, and Absorbers on a TRIGA Spent-Fuel Pool Criticality Safety

    SciTech Connect

    Logar, Marjan; Jeraj, Robert; Glumac, Bogdan

    2003-02-15

    It has been shown that supercriticality might occur for some postulated accident conditions at the TRIGA spent-fuel pool. However, the effect of burnup was not accounted for in previous studies. In this work, the combined effect of fuel burnup, pitch among fuel elements, and number of uniformly mixed absorber rods for a square arrangement on the spent-fuel pool k{sub eff} is investigated.The Monte Carlo computer code MCNP4B with the ENDF-B/VI library and detailed three dimensional geometry was used. The WIMS-D code was used to model the isotopic composition of the standard TRIGA and FLIP fuel for 5, 10, 20 and 30% burnup level and 2- and 4-yr cooling time.The results show that out of the three studied effects, pitch from contact (3.75 cm) up to rack design pitch (8 cm), number of absorbers from zero to eight, and burnup up to 30%, the pitch has the greatest influence on the multiplication factor k{sub eff}. In the interval in which the pitch was changed, k{sub eff} decreased for up to {approx}0.4 for standard and {approx}0.3 for FLIP fuel. The number of absorber rods affects the multiplication factor much less. This effect is bigger for more compact arrangements, e.g., for contact of standard fuel elements with eight absorber rods among them, k{sub eff} values are smaller for {approx}0.2 ({approx}0.1 for FLIP) than for arrangements without absorber rods almost regardless of the burnup. The effect of burnup is the smallest. For standard fuel elements, it is {approx}0.1 for almost all pitches and numbers of absorbers. For FLIP fuel, it is smaller for a factor of 3, but increases with the burnup for compact arrangements. Cooling time of fuel has just a minor effect on the k{sub eff} of spent-fuel pool and can be neglected in spent-fuel pool design.

  11. Optic nerve head analyser and Heidelberg retina tomograph: accuracy and reproducibility of topographic measurements in a model eye and in volunteers.

    PubMed Central

    Janknecht, P; Funk, J

    1994-01-01

    The accuracy and reproducibility of the optic nerve head analyser (ONHA) and the Heidelberg retina tomograph (HRT) were compared and the performance of the HRT in measuring fundus elevations was evaluated. The coefficient of variation of three repeated measurements in a model eye and in volunteers and the relative error in a model eye was calculated. With ONHA measurements the pooled coefficient of variation in volunteers was 9.3% in measuring cup areas and 8.4% in measuring the cup volume. In a model eye the pooled coefficient of variation was 7.6% for the parameter 'cup area' and 9.9% for the parameter 'cup volume'. The pooled relative error in the model eye was 6.6% for the parameter 'cup area' and 5.1% for the parameter 'cup volume'. With HRT measurements in volunteers the pooled coefficient of variation of both the parameters 'volume below contour' and 'volume below surface' was 6.9%. In the model eye the pooled coefficient of variation was 2.4% for the 'volume below contour' and 4.1% for the parameter 'volume below surface'. The pooled relative error in the model eye was 11.3% for the 'volume below contour' and 11% for the 'volume below surface'. The pooled relative error in measuring retinal elevations in the model eye was 3.8%. The coefficient of variation was 3.5%. The accuracies of the HRT and ONHA were similar. However, as the ONHA 'cup volume' is unreliable in patients because of the design of the ONHA whereas the HRT volume parameters are reliable it seems reasonable to assume that the HRT is superior to the ONHA. Only the HRT is capable of quantifying retinal elevations. Images PMID:7803352

  12. Corneal Segmentation Analysis Increases Glaucoma Diagnostic Ability of Optic Nerve Head Examination, Heidelberg Retina Tomograph's Moorfield's Regression Analysis, and Glaucoma Probability Score

    PubMed Central

    Saenz-Frances, F.; Jañez, L.; Berrozpe-Villabona, C.; Borrego-Sanz, L.; Morales-Fernández, L.; Acebal-Montero, A.; Mendez-Hernandez, C. D.; Martinez-de-la-Casa, J. M.; Santos-Bueso, E.; Garcia-Sanchez, J.; Garcia-Feijoo, J.

    2015-01-01

    Purpose. To study whether a corneal thickness segmentation model, consisting in a central circular zone of 1 mm radius centered at the corneal apex (zone I) and five concentric rings of 1 mm width (moving outwards: zones II to VI), could boost the diagnostic accuracy of Heidelberg Retina Tomograph's (HRT's) MRA and GPS. Material and Methods. Cross-sectional study. 121 healthy volunteers and 125 patients with primary open-angle glaucoma. Six binary multivariate logistic regression models were constructed (MOD-A1, MOD-A2, MOD-B1, MOD-B2, MOD-C1, and MOD-C2). The dependent variable was the presence of glaucoma. In MOD-A1, the predictor was the result (presence of glaucoma) of the analysis of the stereophotography of the optic nerve head (ONH). In MOD-B1 and MOD-C1, the predictor was the result of the MRA and GPS, respectively. In MOD-B2 and MOD-C2, the predictors were the same along with corneal variables: central, overall, and zones I to VI thicknesses. This scheme was reproduced for model MOD-A2 (stereophotography along with corneal variables). Models were compared using the area under the receiver operator characteristic curve (AUC). Results. MOD-A1-AUC: 0.771; MOD-A2-AUC: 0.88; MOD-B1-AUC: 0.736; MOD-B2-AUC: 0.845; MOD-C1-AUC: 0.712; MOD-C2-AUC: 0.838. Conclusion. Corneal thickness variables enhance ONH assessment and HRT's MRA and GPS diagnostic capacity. PMID:26180641

  13. Design of a PGAA Facility at the TRIGA Mark III of ININ, Mexico

    SciTech Connect

    Rios-Martinez, C.; Paredes-Gutierrez, L.; Arias, E. Alemon; Ortiz-Romero, M.E.

    2001-06-17

    A thermal neutron prompt gamma activation analysis (PGAA) facility is being developed at the TRIGA-Mark III research reactor, located at the Nabor Carrillo Nuclear Center of the Mexican Institute for Nuclear Research. The PGAA facility is to be built at the exit of a 3.9-m-long radial beam port, which pierces the graphite core reflector. The measured thermal neutron flux at the beam port exit is 0.7 x 10{sup 8} n/cm{sup 2}s, with an epithermal neutron flux of 0.66 x 10{sup 8} n/cm{sup 2}s and a gamma-ray dose of 0.1 Sv/h at full reactor power. Under these circumstances, the extraction of a suitable thermal neutron beam becomes quite challenging. The neutron beam filtering and collimation systems are to be designed for a substantial reduction of the background source components in order to maximize the usable thermal neutron intensity. To obtain reasonable PGAA performance from a filtered low-intensity thermal neutron beam, a Compton suppression feature is added to the detection system. Representative suppressed and unsuppressed spectra of paraffin (hydrogen) neutron capture gamma rays are shown.

  14. Long-lived activation products in TRIGA Mark II research reactor concrete shield: calculation and experiment

    NASA Astrophysics Data System (ADS)

    Žagar, Tomaž; Božič, Matjaž; Ravnik, Matjaž

    2004-12-01

    In this paper, a process of long-lived activity determination in research reactor concrete shielding is presented. The described process is a combination of experiment and calculations. Samples of original heavy reactor concrete containing mineral barite were irradiated inside the reactor shielding to measure its long-lived induced radioactivity. The most active long-lived (γ emitting) radioactive nuclides in the concrete were found to be 133Ba, 60Co and 152Eu. Neutron flux, activation rates and concrete activity were calculated for actual shield geometry for different irradiation and cooling times using TORT and ORIGEN codes. Experimental results of flux and activity measurements showed good agreement with the results of calculations. Volume of activated concrete waste after reactor decommissioning was estimated for particular case of Jožef Stefan Institute TRIGA reactor. It was observed that the clearance levels of some important long-lived isotopes typical for barite concrete (e.g. 133Ba, 41Ca) are not included in the IAEA and EU basic safety standards.

  15. Design of sample carrier for neutron irradiation facility at TRIGA MARK II nuclear reactor

    NASA Astrophysics Data System (ADS)

    Abdullah, Y.; Hamid, N. A.; Mansor, M. A.; Ahmad, M. H. A. R. M.; Yusof, M. R.; Yazid, H.; Mohamed, A. A.

    2013-06-01

    The objective of this work is to design a sample carrier for neutron irradiation experiment at beam ports of research nuclear reactor, the Reaktor TRIGA PUSPATI (RTP). The sample carrier was designed so that irradiation experiment can be performed safely by researchers. This development will resolve the transferring of sample issues faced by the researchers at the facility when performing neutron irradiation studies. The function of sample carrier is to ensure the sample for the irradiation process can be transferred into and out from the beam port of the reactor safely and effectively. The design model used was House of Quality Method (HOQ) which is usually used for developing specifications for product and develop numerical target to work towards and determining how well we can meet up to the needs. The chosen sample carrier (product) consists of cylindrical casing shape with hydraulic cylinders transportation method. The sample placing can be done manually, locomotion was by wheel while shielding used was made of boron materials. The sample carrier design can shield thermal neutron during irradiation of sample so that only low fluencies fast neutron irradiates the sample.

  16. Simulation of Collimator for Neutron Imaging Facility of TRIGA MARK II PUSPATI Reactor

    NASA Astrophysics Data System (ADS)

    Zin, Muhammad Rawi Mohamed; Jamro, Rafhayudi; Yazid, Khairiah; Hussain, Hishamuddin; Yazid, Hafizal; Ahmad, Megat Harun Al Rashid Megat; Azman, Azraf; Mohamad, Glam Hadzir Patai; Hamzah, Nai'im Syaugi; Abu, Mohamad Puad

    Neutron Radiography facility in TRIGA MARK II PUSPATI reactor is being upgraded to obtain better image resolution as well as reducing exposure time. Collimator and exposure room are the main components have been designed for fabrication. This article focuses on the simulation part that was carried out to obtain the profile of collimated neutron beam by utilizing the neutron transport protocol code in the Monte Carlo N-Particle (MCNP) software. Particular interest is in the selection of materials for inlet section of the collimator. Results from the simulation indicates that a combination of Bismuth and Sapphire, each of which has 5.0 cm length that can significantly filter both the gamma radiation and the fast neutrons. An aperture made of Cadmium with 1.0 cm opening diameter provides thermal neutron flux about 1.8 x108 ncm-2s-1 at the inlet, but reduces to 2.7 x106 ncm-2s-1 at the sample plane. Still the flux obtained is expected to reduces exposure time as well as gaining better image resolution.

  17. Critical heat flux in natural convection cooled TRIGA reactors with hexagonal bundle

    SciTech Connect

    Yang, J.; Avery, M.; De Angelis, M.; Anderson, M.; Corradini, M.; Feldman, E. E.; Dunn, F. E.; Matos, J. E.

    2012-07-01

    A three-rod bundle Critical Heat Flux (CHF) study at low flow, low pressure, and natural convection condition has been conducted, simulating TRIGA reactors with the hexagonally configured core. The test section is a custom-made trefoil shape tube with three identical fuel pin heater rods located symmetrically inside. The full scale fuel rod is electrically heated with a chopped-cosine axial power profile. CHF experiments were carried out with the following conditions: inlet water subcooling from 30 K to 95 K; pressure from 110 kPa to 230 kPa; mass flux up to 150 kg/m{sup 2}s. About 50 CHF data points were collected and compared with a few existing CHF correlations whose application ranges are close to the testing conditions. Some tests were performed with the forced convection to identify the potential difference between the CHF under the natural convection and forced convection. The relevance of the CHF to test parameters is investigated. (authors)

  18. Testing the applicability of the k0-NAA method at the MINT's TRIGA MARK II reactor

    NASA Astrophysics Data System (ADS)

    Siong, Wee Boon; Dung, Ho Manh; Wood, Ab. Khalik; Salim, Nazaratul Ashifa Abd.; Elias, Md. Suhaimi

    2006-08-01

    The Analytical Chemistry Laboratory at MINT is using the NAA technique since 1980s and is the only laboratory in Malaysia equipped with a research reactor, namely the TRIGA MARK II. Throughout the years the development of NAA technique has been very encouraging and was made applicable to a wide range of samples. At present, the k0 method has become the preferred standardization method of NAA ( k0-NAA) due to its multi-elemental analysis capability without using standards. Additionally, the k0 method describes NAA in physically and mathematically understandable definitions and is very suitable for computer evaluation. Eventually, the k0-NAA method has been adopted by MINT in 2003, in collaboration with the Nuclear Research Institute (NRI), Vietnam. The reactor neutron parameters ( α and f) for the pneumatic transfer system and for the rotary rack at various locations, as well as the detector efficiencies were determined. After calibration of the reactor and the detectors, the implemented k0 method was validated by analyzing some certified reference materials (including IAEA Soil 7, NIST 1633a, NIST 1632c, NIST 1646a and IAEA 140/TM). The analysis results of the CRMs showed an average u score well below the threshold value of 2 with a precision of better than ±10% for most of the elemental concentrations obtained, validating herewith the introduction of the k0-NAA method at the MINT.

  19. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    SciTech Connect

    Espinosa, G. Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    2015-07-23

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 10{sup 12} n cm{sup −2} s{sup −1}, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer{sup ®} PADC as neutron detection material, covered by 3 mm Plexiglas{sup ®} as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power.

  20. Analysis of higher than normal fuel temperatures in the hexagonal geometry TRIGA reactor

    SciTech Connect

    Hughes, D.; Boyle, P.; Levine, S.H.

    1996-12-31

    The 1-MW Pennsylvania State University TRIGA has hexagonal geometry and a water-filled central thimble. It was operated with all 8.5 wt% U fuel from December 1965 until July 1972, when 12 wt% U fuel elements replaced the 8.5 wt% U fuel in the centermost ring, the B ring. Although the power density of the 12 wt% U fuel was {approximately}35% greater than the corresponding 8.5 wt% U fuel, its maximum steady-state fuel temperature was always below 500{degrees}C when operating at 1 MW. Since that time, the core has been successfully loaded by placing six 12 wt% U fuel elements in the B ring. The used 12 wt% U fuel moved outward. Recently, however, a new instrumented 12 wt% U fuel element initially read a much higher fuel temperature than all previous similar fuel elements. The purpose of this paper is to present the calculations and experiments performed to correlate calculations with experimental data and to determine the cause of the higher fuel temperature for this element.

  1. Triga Mark III Reactor Operating Power and Neutron Flux Study by Nuclear Track Methodology

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    The operating power of a TRIGA Mark III reactor was studied using Nuclear Track Methodology (NTM). The facility has a Highly Enriched Uranium core that provides a neutron flux of around 2 x 1012 n cm-2 s-1 in the TO-2 irradiation channel. The detectors consisted of a Landauer® CR-39 (allyl diglycol polycarbonate) chip covered with a 3 mm Plexiglas® converter. After irradiation, the detectors were chemically etched in a 6.25M-KOH solution at 60±1 °C for 6 h. Track density was determined by a custom-made Digital Image Analysis System. The results show a direct proportionality between reactor power and average nuclear track density for powers in the range 0.1-7 kW. Data reproducibility and relatively low uncertainty (±3%) were achieved. NTM is a simple, fast and reliable technique that can serve as a complementary procedure to measure reactor operating power. It offers the possibility of calibrating the neutron flux density in any low power reactor.

  2. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    2015-07-01

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 1012 n cm-2 s-1, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer® PADC as neutron detection material, covered by 3 mm Plexiglas® as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power.

  3. K/sub infinity/-meter concept verified via subcritical-critical TRIGA experiments

    SciTech Connect

    Ocampo Mansilla, H.

    1983-01-01

    This work presents a technique for building a device to measure the k/sub infinity/ of a spent nuclear fuel assembly discharged from the core of a nuclear power plant. The device, called a k/sub infinity/-meter, consists of a cross-shaped subcritical assembly, two artificial neutron sources, and two separate neutron counting systems. The central position of the subcritical assembly is used to measure k/sub infinity/ of the spent fuel assembly. The initial subcritical assembly is calibrated to determine its k/sub eff/ and verify the assigned k/sub infinity/ of a selected fuel assembly placed in the central position. Count rates are taken with the fuel assembly of known k/sub infinity/'s placed in the central position and then repeated with a fuel assembly of unknown k/sub infinity/ placed in the central position. The count rate ratio of the unknown fuel assembly to the known fuel assembly is used to determine the k/sub infinity/ of the unknown fuel assembly. The k/sub infinity/ of the unknown fuel assembly is represented as a polynomial function of the count rate ratios. The coefficients of the polynomial equation are determined using the neutronic codes LEOPARD and EXTERMINATOR-II. The analytical approach has been validated by performing several subcritical/critical experiments, using the Penn State Breazeale TRIGA Reactor (PSBR), and comparing the experimental results with the calculations.

  4. A Multi-Phased Sampling Effort to Characterize a University TRIGA Research Reactor

    SciTech Connect

    Taylor, K.E.; Holm, R.L.

    2006-07-01

    A radiological characterization project was conducted at the University of Illinois (University) TRIGA research nuclear reactor in July 2005 as part of the long-term facility decommissioning project. The characterization effort included multiple survey and sampling techniques designed to assess both contamination of the reactor building and equipment and activation of reactor components and the reactor bio-shield. Radiation measurements included alpha and beta surface contamination measurements, gamma dose rate measurements, and gross gamma radiation measurements. Modeling was conducted based on the field measurements to predict concentrations of activation products in reactor components that were not directly sampled. The sampling effort included collecting removable contamination swipes, concrete samples from the reactor room floor and bio-shield, soil samples from below and around the perimeter of the reactor building, graphite samples from graphite moderator, and metal samples from reactor components. Concrete samples were obtained using an innovative technology that allowed for quick sample collection and analysis. Concrete, soil, graphite, and metal samples were analyzed on-site using liquid scintillation counters and gamma spectroscopy. Additional samples were sent off-site for analysis. (authors)

  5. Production of 37Ar in The University of Texas TRIGA reactor facility

    SciTech Connect

    Egnatuk, Christine M.; Lowrey, Justin; Biegalski, S.; Bowyer, Ted W.; Haas, Derek A.; Orrell, John L.; Woods, Vincent T.; Keillor, Martin E.

    2011-06-19

    The detection of {sup 37}Ar is important for on-site inspections for the Comprehensive Nuclear-Test-Ban Treaty monitoring. In an underground nuclear explosion this radionuclide is produced by {sup 40}Ca(n,{alpha}){sup 37}Ar reaction in surrounding soil and rock. With a half-life of 35 days, {sup 37}Ar provides a signal useful for confirming the location of an underground nuclear event. An ultra-low-background proportional counter developed by Pacific Northwest National Laboratory is used to detect {sup 37}Ar, which decays via electron capture. The irradiation of Ar gas at natural enrichment in the 3L facility within the Mark II TRIGA reactor facility at The University of Texas at Austin provides a source of {sup 37}Ar for the calibration of the detector. The {sup 41}Ar activity is measured by the gamma activity using an HPGe detector after the sample is removed from the core. Using the {sup 41}Ar/{sup 37}Ar production ratio and the {sup 41}Ar activity, the amount of {sup 37}Ar created is calculated. The {sup 41}Ar decays quickly (half-life of 109.34 minutes) leaving a radioactive sample of high purity {sup 37}Ar and only trace levels of {sup 39}Ar.

  6. TRIGA reactor facility at the Armed Forces Radiobiology Research Institute: a simplified technical description. Technical report

    SciTech Connect

    Moore, M.L.; Elsasser, S.

    1986-05-01

    In support of its mission the Armed Forces Radiobiology Research Institute (AFRRI) operates a medium-sized research nuclear reactor. The reactor is used to generate radiations, primarily neutrons and gamma rays, which are used to conduct experimental biomedical research and to produce isotopes. The radiations are delivered to the experiments in one of two ways: a pulse operation delivers a very short burst of high power, or a steady-state operation delivers a longer, continuous low- to medium-power exposure. The reactor is also used to train military personnel in reactor operations. TRIGA is an acronym for Training, Research, and Isotope, General Atomics. Mark-F is the specific General Atomics Reactor model, distinguished by a pool, a movable core, exposure-room facilities, and the ability to pulse to momentary high powers. Reactor operations at AFRRI began is 1962. In 1965, a change was made from aluminum-clad to stainless steel-clad fuel elements. Currently more than 150 multiple exposure experiments are performed each year using the reactor.

  7. Neutronic and thermal-hydraulic analysis of new irradiation channels inside the Moroccan TRIGA Mark II research reactor core.

    PubMed

    Chham, E; El Bardouni, T; Benaalilou, K; Boukhal, H; El Bakkari, B; Boulaich, Y; El Younoussi, C; Nacir, B

    2016-10-01

    This study was conducted to improve the capacity of radioisotope production in the Moroccan TRIGA Mark II research reactor, which is considered as one of the most important applications of research reactors. The aim of this study is to enhance the utilization of TRIGA core in the field of neutron activation and ensure an economic use of the fuel. The main idea was to create an additional irradiation channel (IC) inside the core. For this purpose, three new core configurations are proposed, which differ according to the IC position in the core. Thermal neutron flux distribution and other neutronic safety parameters such as power peaking factors, excess reactivity, and control rods worth reactivity were calculated using the Monte Carlo N-Particle Transport (MCNP) code and neutron cross-section library based on ENDF/B-VII evaluation. The calculated thermal flux in the central thimble (CT) and in the added IC for the reconfigured core is compared with the thermal flux in the CT of the existing core, which is taken as a reference. The results show that all the obtained fluxes in CTs are very close to the reference value, while a remarkable difference is observed between the fluxes in the new ICs and reference. This difference depends on the position of IC in the reactor core. To demonstrate that the Moroccan TRIGA reactor could safely operate at 2MW, with new configurations based on new ICs, different safety-related thermal-hydraulic parameters were investigated. The PARET model was used in this study to verify whether the safety margins are met despite the new modifications of the core. The results show that it is possible to introduce new ICs safely in the reactor core, because the obtained values of the parameters are largely far from compromising the safety of the reactor. PMID:27552124

  8. Extraction of pure thermal neutron beam for the proposed PGNAA facility at the TRIGA research reactor of AERE, Savar, Bangladesh

    NASA Astrophysics Data System (ADS)

    Alam, Sabina; Zaman, M. A.; Islam, S. M. A.; Ahsan, M. H.

    1993-10-01

    A study on collimators and filters for the design of a spectrometer for prompt gamma neutron activation analysis (PGNAA) at one of the radial beamports of the TRIGA Mark II reactor at AERE, Savar has been carried out. On the basis of this study a collimator and a filter have been designed for the proposed PGNAA facility. Calculations have been done for measuring neutron flux at various positions of the core of the reactor using the computer code TRIGAP. Gamma dose in the core of the reactor has also been measured experimentally using TLD technique in the present work.

  9. Neutron flux measurements at the TRIGA reactor in Vienna for the prediction of the activation of the biological shield.

    PubMed

    Merz, Stefan; Djuricic, Mile; Villa, Mario; Böck, Helmuth; Steinhauser, Georg

    2011-11-01

    The activation of the biological shield is an important process for waste management considerations of nuclear facilities. The final activity can be estimated by modeling using the neutron flux density rather than the radiometric approach of activity measurements. Measurement series at the TRIGA reactor Vienna reveal that the flux density next to the biological shield is in the order of 10(9)cm(-2)s(-1) at maximum power; but it is strongly influenced by reactor installations. The data allow the estimation of the final waste categorization of the concrete according to the Austrian legislation. PMID:21646026

  10. Conversion of TRIGA research reactors from high-enriched- to low-enriched-uranium fuels: owner/operator view

    SciTech Connect

    Feltz, D.E.

    1986-01-01

    In June 1985, the US Nuclear Regulatory Commission (NRC) commissioners issued a four-point directive to the NRC staff concerning the conversion of research reactors from the use of high-enriched-uranium (HEU) to low-enriched-uranium (LEU) fuels. As a result of this directive, the earlier concerns of the research reactor community that were presented to the NRC during the comment period of the 1984 proposed rule on HEU-LEU conversion must be dealt with now. This paper discusses the items of most concern to HEU TRIGA owner/operators for conversion to LEU fuel.

  11. Dose Calculations for the Co-Disposal WP-of HLW-Glass and the Triga SNF

    SciTech Connect

    G. Radulescu

    1999-08-02

    This calculation is prepared by the Monitored Geologic Repository (MGR) Waste Package Operations (WPO). The purpose of this calculation is to determine the surface dose rates of a codisposal waste package (WP) containing a centrally located Department of Energy (DOE) standardized 18-in. spent nuclear fuel (SNF) canister, loaded with the TRIGA (Training, Research, Isotopes, General Atomics) SNF. This canister is surrounded by five 3-m long canisters, loaded with Savannah River Site (SRS) high-level waste (HLW) glass. The results are to support the WP design and radiological analyses.

  12. Conceptual Design of a Clinical BNCT Beam in an Adjacent Dry Cell of the Jozef Stefan Institute TRIGA Reactor

    SciTech Connect

    Maucec, Marko

    2000-11-15

    The MCNP4B Monte Carlo transport code is used in a feasibility study of the epithermal neutron boron neutron capture therapy facility in the thermalizing column of the 250-kW TRIGA Mark II reactor at the Jozef Stefan Institute (JSI). To boost the epithermal neutron flux at the reference irradiation point, the efficiency of a fission plate with almost 1.5 kg of 20% enriched uranium and 2.3 kW of thermal power is investigated. With the same purpose in mind, the TRIGA reactor core setup is optimized, and standard fresh fuel elements are concentrated partly in the outermost ring of the core. Further, a detailed parametric study of the materials and dimensions for all the relevant parts of the irradiation facility is carried out. Some of the standard epithermal neutron filter/moderator materials, as well as 'pressed-only' low-density Al{sub 2}O{sub 3} and AlF{sub 3}, are considered. The proposed version of the BNCT facility, with PbF{sub 2} as the epithermal neutron filter/moderator, provides an epithermal neutron flux of {approx}1.1 x 10{sup 9} n/cm{sup 2}.s, thus enabling patient irradiation times of <60 min. With reasonably low fast neutron and photon contamination ([overdot]D{sub nfast}/{phi}{sub epi} < 5 x 10{sup -13} Gy.cm{sup 2}/n and [overdot]D{sub {gamma}} /{phi}{sub epi} < 3 x 10{sup -13} Gy.cm{sup 2}/n), the in-air performances of the proposed beam are comparable to all existing epithermal BNCT facilities. The design presents an equally efficient alternative to the BNCT beams in TRIGA reactor thermal columns that are more commonly applied. The cavity of the dry cell, a former JSI TRIGA reactor spent-fuel storage facility, adjacent to the thermalizing column, could rather easily be rearranged into a suitable patient treatment room, which would substantially decrease the overall developmental costs.

  13. Usefulness of High-Quality Core Genome Single-Nucleotide Variant Analysis for Subtyping the Highly Clonal and the Most Prevalent Salmonella enterica Serovar Heidelberg Clone in the Context of Outbreak Investigations.

    PubMed

    Bekal, S; Berry, C; Reimer, A R; Van Domselaar, G; Beaudry, G; Fournier, E; Doualla-Bell, F; Levac, E; Gaulin, C; Ramsay, D; Huot, C; Walker, M; Sieffert, C; Tremblay, C

    2016-02-01

    Salmonella enterica serovar Heidelberg is the second most frequently occurring serovar in Quebec and the third-most prevalent in Canada. Given that conventional pulsed-field gel electrophoresis (PFGE) subtyping for common Salmonella serovars, such as S. Heidelberg, yields identical subtypes for the majority of isolates recovered, public health laboratories are desperate for new subtyping tools to resolve highly clonal S. Heidelberg strains involved in outbreak events. As PFGE was unable to discriminate isolates from three epidemiologically distinct outbreaks in Quebec, this study was conducted to evaluate whole-genome sequencing (WGS) and phylogenetic analysis as an alternative to conventional subtyping tools. Genomes of 46 isolates from 3 Quebec outbreaks (2012, 2013, and 2014) supported by strong epidemiological evidence were sequenced and analyzed using a high-quality core genome single-nucleotide variant (hqSNV) bioinformatics approach (SNV phylogenomics [SNVphyl] pipeline). Outbreaks were indistinguishable by conventional PFGE subtyping, exhibiting the same PFGE pattern (SHEXAI.0001/SHEBNI.0001). Phylogenetic analysis based on hqSNVs extracted from WGS separated the outbreak isolates into three distinct groups, 100% concordant with the epidemiological data. The minimum and maximum number of hqSNVs between isolates from the same outbreak was 0 and 4, respectively, while >59 hqSNVs were measured between 2 previously indistinguishable outbreaks having the same PFGE and phage type, thus corroborating their distinction as separate unrelated outbreaks. This study demonstrates that despite the previously reported high clonality of this serovar, the WGS-based hqSNV approach is a superior typing method, capable of resolving events that were previously indistinguishable using classic subtyping tools. PMID:26582830

  14. Usefulness of High-Quality Core Genome Single-Nucleotide Variant Analysis for Subtyping the Highly Clonal and the Most Prevalent Salmonella enterica Serovar Heidelberg Clone in the Context of Outbreak Investigations

    PubMed Central

    Berry, C.; Reimer, A. R.; Van Domselaar, G.; Beaudry, G.; Fournier, E.; Doualla-Bell, F.; Levac, E.; Gaulin, C.; Ramsay, D.; Huot, C.; Walker, M.; Sieffert, C.; Tremblay, C.

    2015-01-01

    Salmonella enterica serovar Heidelberg is the second most frequently occurring serovar in Quebec and the third-most prevalent in Canada. Given that conventional pulsed-field gel electrophoresis (PFGE) subtyping for common Salmonella serovars, such as S. Heidelberg, yields identical subtypes for the majority of isolates recovered, public health laboratories are desperate for new subtyping tools to resolve highly clonal S. Heidelberg strains involved in outbreak events. As PFGE was unable to discriminate isolates from three epidemiologically distinct outbreaks in Quebec, this study was conducted to evaluate whole-genome sequencing (WGS) and phylogenetic analysis as an alternative to conventional subtyping tools. Genomes of 46 isolates from 3 Quebec outbreaks (2012, 2013, and 2014) supported by strong epidemiological evidence were sequenced and analyzed using a high-quality core genome single-nucleotide variant (hqSNV) bioinformatics approach (SNV phylogenomics [SNVphyl] pipeline). Outbreaks were indistinguishable by conventional PFGE subtyping, exhibiting the same PFGE pattern (SHEXAI.0001/SHEBNI.0001). Phylogenetic analysis based on hqSNVs extracted from WGS separated the outbreak isolates into three distinct groups, 100% concordant with the epidemiological data. The minimum and maximum number of hqSNVs between isolates from the same outbreak was 0 and 4, respectively, while >59 hqSNVs were measured between 2 previously indistinguishable outbreaks having the same PFGE and phage type, thus corroborating their distinction as separate unrelated outbreaks. This study demonstrates that despite the previously reported high clonality of this serovar, the WGS-based hqSNV approach is a superior typing method, capable of resolving events that were previously indistinguishable using classic subtyping tools. PMID:26582830

  15. Spatial variation in quartz cement type and concentration: An example from the Heidelberg formation (Teufelsmauer outcrops), Upper Cretaceous Subhercynian Basin, Germany

    NASA Astrophysics Data System (ADS)

    Fischer, Cornelius; Waldmann, Svenja; von Eynatten, Hilmar

    2013-06-01

    Spatial heterogeneity of cement abundance in sandstones is an important factor for reservoir compartmentalization. Here we present results on the variety of diagenetic products and spatial distribution of intense and focused silica cementation within otherwise friable sandstone without silica cements. The Cretaceous quartz arenite of the Teufelsmauer outcrops near Quedlinburg (Upper Cretaceous Heidelberg formation, Subhercynian Basin, Germany) is cemented by various types of diagenetic silica. The highly cemented sandstone sections contain both syntaxial quartz cement (concentrations: 11-31 vol.%) and microcrystalline pore-filling quartz cement (10-34 vol.%). Microcrystalline cement generations form the latest SiO2 precipitations and overgrow moderate to intense syntaxial rims. At outcrop and sedimentary basin scales, the occurrence of highly cemented sandstone is limited to an area of several hundreds of meters in lateral extension, but does not exceed a layer thickness of about 5 m. The highly cemented sandstone shows internal heterogeneity in cementation with preferred orientation of their length axis, suggesting mainly stationary fluid flow pathways during cementation of several silica generations. Most likely, the source of all diagenetic silica is owing to enhanced dissolution at cataclastic deformation bands, which are found within the same sandstone strata. As a mechanism for locally focused precipitation, we suggest a combination of (1) local enhancement of silica dissolution due to deformation and cataclasis and (2) enhanced fluid flow and expulsion during deformation related to the synchronous thrusting of the Harz block onto the Cretaceous Subhercynian Basin. We interpret that the expelled silica-enriched formation water experienced fluid mixing with ascending water from an overpressured, deeper regime, implying that the observed silica generations trace this unique zone of fluid expulsion, ascension, and mixing. Our investigations show that silica

  16. First measurements of continuous δ18O-CO2 with a Fourier Transform InfraRed spectrometer in Heidelberg, Germany

    NASA Astrophysics Data System (ADS)

    Vardag, S. N.; Hammer, S.; Sabasch, M.; Griffith, D. W. T.; Levin, I.

    2014-07-01

    The continuous in-situ measurement of δ18O in atmospheric CO2 opens a new door to differentiating between CO2 source and sink components with high temporal resolution. Continuous 13C-CO2 measurement systems have been commercially available already for some time, but until now, only few instruments have been able to provide a continuous measurement of the oxygen isotope ratio in CO2. Besides precise 13C/12C observations, the Fourier Transform InfraRed (FTIR) spectrometer also measures the 18O/16O ratio of CO2, but the precision and accuracy of the measurements has not been evaluated yet. Here we present a first analysis of δ18O-CO2 (and δ13C-CO2) measurements with the FTIR in Heidelberg. We find that our spectrometer measures 18O in CO2 with a reproducibility of better than 0.3‰ at a temporal resolution of less than 10 min, as determined from surveillance gas measurements over a period of ten months. An Allan deviation test shows that the δ18O repeatability reaches 0.15‰ for half-hourly means. The compatibility of our spectroscopic measurements was determined by comparing FTIR measurements of calibration gases and ambient air to mass-spectrometric measurements of flask samples, filled with the cylinder gases or episodically collected over a diurnal cycle (event). We found that direct cylinder gas measurements agree to 0.01 ± 0.04‰ (mean and standard deviation) for δ13C-CO2 and 0.01 ± 0.11‰ for δ18O. Two weekly episodes of recent ambient air measurements, one in winter and one in summer, are discussed in view of the question, which potential insights and new challenges combined highly resolved δ18O-CO2 and δ13C-CO2 records may provide in terms of better understanding regional scale continental carbon exchange processes.

  17. Confirmation of a realistic reactor model for BNCT dosimetry at the TRIGA Mainz

    SciTech Connect

    Ziegner, Markus; Schmitz, Tobias; Hampel, Gabriele; Khan, Rustam; Blaickner, Matthias; Palmans, Hugo; Sharpe, Peter; Böck, Helmuth

    2014-11-01

    Purpose: In order to build up a reliable dose monitoring system for boron neutron capture therapy (BNCT) applications at the TRIGA reactor in Mainz, a computer model for the entire reactor was established, simulating the radiation field by means of the Monte Carlo method. The impact of different source definition techniques was compared and the model was validated by experimental fluence and dose determinations. Methods: The depletion calculation code ORIGEN2 was used to compute the burn-up and relevant material composition of each burned fuel element from the day of first reactor operation to its current core. The material composition of the current core was used in a MCNP5 model of the initial core developed earlier. To perform calculations for the region outside the reactor core, the model was expanded to include the thermal column and compared with the previously established ATTILA model. Subsequently, the computational model is simplified in order to reduce the calculation time. Both simulation models are validated by experiments with different setups using alanine dosimetry and gold activation measurements with two different types of phantoms. Results: The MCNP5 simulated neutron spectrum and source strength are found to be in good agreement with the previous ATTILA model whereas the photon production is much lower. Both MCNP5 simulation models predict all experimental dose values with an accuracy of about 5%. The simulations reveal that a Teflon environment favorably reduces the gamma dose component as compared to a polymethyl methacrylate phantom. Conclusions: A computer model for BNCT dosimetry was established, allowing the prediction of dosimetric quantities without further calibration and within a reasonable computation time for clinical applications. The good agreement between the MCNP5 simulations and experiments demonstrates that the ATTILA model overestimates the gamma dose contribution. The detailed model can be used for the planning of structural

  18. Results of the MCNP analysis of 20/20 LEU fuel for the Oregon State University TRIGA Reactor

    SciTech Connect

    Dodd, B.; Klein, A.C.; Lewis, B.R.; Merritt, P.A.

    1995-12-31

    The Monte Carlo Neutron/Photon (MCNP) code has been used to perform the neutronics analysis required to support revision of the Oregon State University TRIGA Reactor (OSTR) Safety Analysis Report (SAR). The SAR revision is a necessary part of the preparation of the application for authorization to convert the OSTR core from High Enriched Uranium (HEU) FLIP fuel to a Low Enriched Uranium (LEU) fuel. Before MCNP was applied to LEU-fueled cores, it was first validated by comparing MCNP calculations on FLIP cores to historical, measured values for these cores. The LEU fuel considered was the 20 wt%, 20% enriched (20/20) TRIGA fuel approved by the Nuclear Regulatory Commission (NRC) in NUREG 1282. The results show that the 20/20 fuel is much more reactive than FLIP fuel. A just-critical OSTR FLIP core contains 65 elements, while a just-critical 20/20 core only needs 51 elements. Similarly, the current operational FLIP core consists of 88 elements, whereas a 20/20 core giving the same core excess only requires 65 elements. This presents a significant problem for the OSTR because of potentially significant neutron flux loss in experimental facilities. Further analysis shows that to achieve a full size operational core of about 90 LEU elements the erbium content of the LEU fuel would need to be increased from 0.47wt% to about 0.85 wt%.

  19. Results of the MCNP analysis of 20/20 LEU fuel for the Oregon State University TRIGA reactor

    SciTech Connect

    Dodd, B.; Klein, A.C.; Lewis, B.R.; Merritt, P.A

    1994-07-01

    The Monte Carlo Neutron/Photon (MCNP) code has been used to perform the neutronics analysis required to support revision of the Oregon State University TRIGA Reactor (OSTR) Safety Analysis Report (SAR). The SAR revision is a necessary part of the preparation of the application for authorization to convert the OSTR core from High Enriched Uranium (HEU) FLIP fuel to a Low Enriched Uranium (LEU) fuel. Before MCNP was applied to LEU-fueled cores, it was first validated by comparing MCNP calculations on FLIP cores to historical, measured values for these cores. The LEU fuel considered was the 20 wt%, 20 % enriched (20/20) TRIGA fuel approved by the Nuclear Regulatory Commission (NRC) in NUREG 1282. The results show that the 20/20 fuel is much more reactive than FLIP fuel. A just-critical OSTR FLIP core contains 65 elements, while a just-critical 20/20 core only needs 51 elements. Similarly, the current operational FLIP core consists of 88 elements, whereas a 20/20 core giving the same core excess only requires 65 elements. This presents a significant problem for the OSTR because of potentially significant neutron flux loss in experimental facilities. Further analysis shows that to achieve a full size operational core of about 90 LEU elements the erbium content of the LEU fuel would need to be increased from 0.47 wt% to about 0.85 wt%. (author)

  20. Implementation of k0-INAA standardisation at ITU TRIGA Mark II research reactor, Turkey based on k0-IAEA software

    NASA Astrophysics Data System (ADS)

    Esen, Ayse Nur; Haciyakupoglu, Sevilay

    2016-02-01

    The purpose of this study is to test the applicability of k0-INAA method at the Istanbul Technical University TRIGA Mark II research reactor. The neutron spectrum parameters such as epithermal neutron flux distribution parameter (α), thermal to epithermal neutron flux ratio (f) and thermal neutron flux (φth) were determined at the central irradiation channel of the ITU TRIGA Mark II research reactor using bare triple-monitor method. HPGe detector calibrations and calculations were carried out by k0-IAEA software. The α, f and φth values were calculated to be -0.009, 15.4 and 7.92·1012 cm-2 s-1, respectively. NIST SRM 1633b coal fly ash and intercomparison samples consisting of clay and sandy soil samples were used to evaluate the validity of the method. For selected elements, the statistical evaluation of the analysis results was carried out by z-score test. A good agreement between certified/reported and experimental values was obtained.

  1. Validating the Serpent Model of FiR 1 Triga Mk-II Reactor by Means of Reactor Dosimetry

    NASA Astrophysics Data System (ADS)

    Viitanen, Tuomas; Leppänen, Jaakko

    2016-02-01

    A model of the FiR 1 Triga Mk-II reactor has been previously generated for the Serpent Monte Carlo reactor physics and burnup calculation code. In the current article, this model is validated by comparing the predicted reaction rates of nickel and manganese at 9 different positions in the reactor to measurements. In addition, track-length estimators are implemented in Serpent 2.1.18 to increase its performance in dosimetry calculations. The usage of the track-length estimators is found to decrease the reaction rate calculation times by a factor of 7-8 compared to the standard estimator type in Serpent, the collision estimators. The differences in the reaction rates between the calculation and the measurement are below 20%.

  2. ["Should the staff's attitude towards the patients remain unchanged, I will not guarantee anything." Protest masculinity and coping of "rebellious patients" at the Heidelberg University Psychiatric Hospital on the eve of deinstitutionalization].

    PubMed

    Schwamm, Christoph

    2015-01-01

    This article analyses the illness experiences of male patients from the Heidelberg University Psychiatric Hospital during the protests against Psychiatry in the year 1973. Protest is one of the most important expressions of masculinity in socially disadvantaged men, such as men with mental disorders. The analysis of 100 medical records shows that some patients tried to construct themselves as men in a way that was explicitly motivated by antipsychiatric ideas: They questioned psychiatric authority, behaved "sexually inappropriate", or used drugs. On the eve of psychiatric reform in West Germany those patients were well aware that the alternative--complying with the treatment--would put them at considerable risk. In addition to the usual inference of hegemonic or normative masculinities as risk-factors, the behavior of those ,,rebellious patients" has to be interpreted as individual coping strategies. PMID:26219192

  3. Mass measurements on stable nuclides in the rare-earth region with the Penning-trap mass spectrometer TRIGA-TRAP

    NASA Astrophysics Data System (ADS)

    Ketelaer, J.; Audi, G.; Beyer, T.; Blaum, K.; Block, M.; Cakirli, R. B.; Casten, R. F.; Droese, C.; Dworschak, M.; Eberhardt, K.; Eibach, M.; Herfurth, F.; Minaya Ramirez, E.; Nagy, Sz.; Neidherr, D.; Nörtershäuser, W.; Smorra, C.; Wang, M.

    2011-07-01

    The masses of 15 stable nuclides in the rare-earth region have been measured with the Penning-trap mass spectrometer TRIGA-TRAP. This is the first series of absolute mass measurements linking these nuclides to the atomic-mass standard C12. Previously, nuclear reaction studies almost exclusively determined the literature values of these masses in the Atomic-Mass Evaluation. The TRIGA-TRAP results show deviations on the order of 3-4 standard deviations from the latest published values of the Atomic-Mass Evaluation 2003 for some cases. However, the binding-energy differences that are important for nuclear structure studies have been confirmed and improved. The new masses are discussed in the context of valence proton-neutron interactions using double differences of binding energies, δVpn(Z,N).

  4. Mass measurements on stable nuclides in the rare-earth region with the Penning-trap mass spectrometer TRIGA-TRAP

    SciTech Connect

    Ketelaer, J.; Audi, G.; Beyer, T.; Blaum, K.; Block, M.; Dworschak, M.; Herfurth, F.; Cakirli, R. B.; Casten, R. F.; Droese, C.; Eberhardt, K.; Eibach, M.; Smorra, C.; Minaya Ramirez, E.; Nagy, Sz.; Neidherr, D.; Noertershaeuser, W.; Wang, M.

    2011-07-15

    The masses of 15 stable nuclides in the rare-earth region have been measured with the Penning-trap mass spectrometer TRIGA-TRAP. This is the first series of absolute mass measurements linking these nuclides to the atomic-mass standard {sup 12}C. Previously, nuclear reaction studies almost exclusively determined the literature values of these masses in the Atomic-Mass Evaluation. The TRIGA-TRAP results show deviations on the order of 3-4 standard deviations from the latest published values of the Atomic-Mass Evaluation 2003 for some cases. However, the binding-energy differences that are important for nuclear structure studies have been confirmed and improved. The new masses are discussed in the context of valence proton-neutron interactions using double differences of binding energies, {delta}V{sub pn}(Z,N).

  5. Comparison of EPR response of alanine and Gd₂O₃-alanine dosimeters exposed to TRIGA Mainz reactor.

    PubMed

    Marrale, M; Schmitz, T; Gallo, S; Hampel, G; Longo, A; Panzeca, S; Tranchina, L

    2015-12-01

    In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of alanine pellets. Monte Carlo (MC) simulations of both response of alanine and Gd-added alanine pellets with FLUKA code were performed and a good agreement was achieved for pure alanine dosimeters. For Gd2O3-alanine deviations between MC simulations and experimental data were observed and discussed. PMID:26315099

  6. Adaptation of triple axis neutron spectrometer for SANS measurements using alumina samples at TRIGA reactor of Bangladesh

    NASA Astrophysics Data System (ADS)

    Ahmed, F. U.; Kamal, I.; Yunus, S. M.; Datta, T. K.; Azad, A. K.; Zakaria, A. K. M.; Goyal, P. S.

    2005-09-01

    Double crystal method known as Bonse and Hart's technique has been employed to develop small angle neutron scattering (SANS) facility on a triple axis neutron spectrometer at TRIGA Mark II (3 MW) research reactor of Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh. Two Si(1 1 1) crystals with very small mosaic spread ∼1 min have been used for this purpose. At an incident neutron wavelength of 1.24 Å, this device is useful for SANS in the Q range between 1.6×10 -3 and 10 -1 Å -1. This Q range allows investigating particle sizes and interparticle correlations on a length scale of ∼200 Å. Results of SANS experiments on three alumina (Al 2O 3) samples as performed using above setup are presented. It is seen that Al 2O 3 particles, indeed, scatter neutrons in regions of small angles. It is also seen that scattering is different for different samples showing that it changes with a change in particle size.

  7. OREGON STATE UNIVERSITY (OSU) TRAINING RESEARCH ISOTOPE GENERAL ATOMICS (TRIGA) OVERPACK CLOSURE WELDING PROCESS PARAMETER DEVELOPMENT & QUALIFICATION

    SciTech Connect

    CANNELL, G.R.

    2006-09-11

    Spent Nuclear Fuel (SNF) from the Oregon State University (OSU) TRIGA{reg_sign} Reactor is currently being stored in thirteen 55-gallon drums at the Hanford Site's low-level burial grounds. This fuel is soon to be retrieved from buried storage and packaged into new containers (overpacks) for interim storage at the Hanford Interim Storage Area (ISA). One of the key activities associated with this effort is final closure of the overpack by welding. The OSU fuel is placed into an overpack, a head inserted into the overpack top, and welded closed. Weld quality, for typical welded fabrication, is established through post-weld testing and nondestructive examination (NDE); however, in this case, once the SNF is placed into the overpack, routine testing and NDE are not feasible. An alternate approach is to develop and qualify the welding process/parameters, demonstrate beforehand that they produce the desired weld quality, and then verify parameter compliance during production welding. Fluor engineers have developed a Gas Tungsten Arc Welding (GTAW) technique and parameters, demonstrating that weld quality requirements for closure of packaged SNF overpacks are met, using this alternate approach. The following reviews the activities performed for this development and qualification effort.

  8. Active in-core irradiation of SiC JFETs at 300 C in a TRIGA nuclear reactor

    SciTech Connect

    McGarrity, J.; Scozzie, C.; Blackburn, J.; DeLancey, M.

    1996-12-31

    In this paper the authors demonstrate that SiC transistors have the potential to operate in the severe high temperature and radiation environments of commercial and space nuclear power sources. 6H-SiC FETs were exposed to neutron fluxes and gamma dose rates as high as 1.6 {times} 10{sup 12} n/cm{sup 2}/sec and 3.8 {times} 10{sup 4} rad(Si)/sec while they were maintained under bias at both 300 C and room temperature within the core of a TRIGA reactor operated at 200 kW power level. The radiation exposure was continuous and the bias on the devices was interrupted only to record the current-voltage characteristics at various accumulated neutron fluences from 10{sup 13} to 5 {times} 10{sup 15} n/cm{sup 2}. No significant degradation in the device characteristics was observed until the total neutron fluence exceeded 10{sup 15} n/cm{sup 2} for irradiation at 25 C, and no significant changes were observed even at 5 {times} 10{sup 15} n/cm{sup 2} at 300 C.

  9. Estimation of (41)Ar activity concentration and release rate from the TRIGA Mark-II research reactor.

    PubMed

    Hoq, M Ajijul; Soner, M A Malek; Rahman, A; Salam, M A; Islam, S M A

    2016-03-01

    The BAEC TRIGA research reactor (BTRR) is the only nuclear reactor in Bangladesh. Bangladesh Atomic Energy Regulatory Authority (BAERA) regulations require that nuclear reactor licensees undertake all reasonable precautions to protect the environment and the health and safety of persons, including identifying, controlling and monitoring the release of nuclear substances to the environment. The primary activation product of interest in terms of airborne release from the reactor is (41)Ar. (41)Ar is a noble gas readily released from the reactor stacks and most has not decayed by the time it moves offsite with normal wind speed. Initially (41)Ar is produced from irradiation of dissolved air in the primary water which eventually transfers into the air in the reactor bay. In this study, the airborne radioisotope (41)Ar generation concentration, ground level concentration and release rate from the BTRR bay region are evaluated theoretically during the normal reactor operation condition by several governing equations. This theoretical calculation eventually minimizes the doubt about radiological safety to determine the radiation level for (41)Ar activity whether it is below the permissible limit or not. Results show that the estimated activity for (41)Ar is well below the maximum permissible concentration limit set by the regulatory body, which is an assurance for the reactor operating personnel and general public. Thus the analysis performed within this paper is so much effective in the sense of ensuring radiological safety for working personnel and the environment. PMID:26736180

  10. Analytical analyses of startup measurements associated with the first use of LEU fuel in Romania's 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.; Snelgrove, J.L. ); Ciocanescu, M. )

    1992-01-01

    The 14-MW TRIGA steady state reactor (SSR) is located in Pitesti, Romania. Beginning with an HEU core (10 wt% U), the reactor first went critical in November 1979 but was shut down ten years later because of insufficient excess reactivity. Last November the Institute for Nuclear Research (INR), which operates the SSR, received from the ANL RERTR program a shipment of 125 LEU pins fabricated by General Atomics and of the same geometry as the original fuel but with an enrichment of 19.7% 235U and a loading of 45 wt% U. Using 100 of these pins, four LEU clusters, each containing a 5 x 5 square array of fuel rods, were assembled. These four LEU clusters replaced the four most highly burned HEU elements in the SSR. The reactor resumed operations last February with a 35-element mixed HEU/LEU core configuration. In preparation for full power operation of the SSR with this mixed HEU/LEU core, a number of measurements were made. These included control rod calibrations, excess reactivity determinations, worths of experiment facilities, reaction rate distributions, and themocouple measurements of fuel temperatures as a function of reactor power. This paper deals with a comparison of some of these measured reactor parameters with corresponding analytical calculations.

  11. Lifetime measurement of the Ar XIV 1s{sup 2}2s{sup 2}2p {sup 2}P{sub 3/2}{sup o} metastable level at the Heidelberg electron-beam ion trap

    SciTech Connect

    Lapierre, A.; Crespo Lopez-Urrutia, J. R.; Braun, J.; Brenner, G.; Bruhns, H.; Fischer, D.; Gonzalez Martinez, A. J.; Mironov, V.; Osborne, C.; Sikler, G.; Soria Orts, R.; Tawara, H.; Ullrich, J.; Shabaev, V. M.; Tupitsyn, I. I.; Volotka, A.

    2006-05-15

    We present the details of an accurate lifetime measurement of the 1s{sup 2}2s{sup 2}2p {sup 2}P{sub 3/2}{sup o} metastable level in boronlike Ar XIV performed at the Heidelberg electron beam ion trap [A. Lapierre et al., Phys. Rev. Lett. 95, 183001 (2005)]. The lifetime was inferred from decay curves resulting from deexcitation of the metastable level to its {sup 2}P{sub 1/2}{sup o} ground state through a magnetic-dipole (M1) transition upon cyclically turning on and off the electron beam. The measured lifetime of 9.573(4)((+12/-5)) ms (stat)(syst) is in disagreement with a trend of theoretical predictions of 9.53(1) ms, which include the effect of the electron anomalous magnetic moment. Systematic effects were investigated by studying with high statistical significance the dependence of the decay times of the curves on various trapping conditions. The asymptotic trend of the decay times observed for increasingly high trapping potentials, which indicates negligible ion losses within a ms time scale, is in agreement with a theoretical model describing the ion escape rate in electrostatic ion traps. However, for high trapping potentials, we observed an unexpected slowly decaying component suggesting the presence of trapped low-energy electrons. Their origin, dynamics, and temperature, as well as their possible effects on the measured lifetime were investigated.

  12. Calculation of the Activity Inventory for the TRIGA Reactor at the Medical University of Hannover (MHH) in Preparation for Dismantling the Facility

    SciTech Connect

    Hampel, G.; Scheller, F.; Bernnat, W.; Pfister, G.; Klaux, U.; Gerhards, E.

    2002-02-25

    It is planned to dismantle the TRIGA reactor facility at the Medical University of Hannover (MHH). Radioactive waste resulting from this dismantling will be disposed of externally, any remaining materials as well as the building structures will then be measured to ensure there is no residual activity. In preparation for this and to plan the techniques which will be used to dismantle the reactor, calculations were made in order to determine the amount of activity and the dose rates for the reactor tank and its inside components as well as for the biological shield and its radial beam tube.

  13. A high performance neutron powder diffractometer at 3 MW Triga Mark-II research reactor in Bangladesh

    NASA Astrophysics Data System (ADS)

    Kamal, I.; Yunus, S. M.; Datta, T. K.; Zakaria, A. K. M.; Das, A. K.; Aktar, S.; Hossain, S.; Berliner, R.; Yelon, W. B.

    2016-07-01

    A high performance neutron diffractometer called Savar Neutron Diffractometer (SAND) was built and installed at radial beam port-2 of TRIGA Mark II research reactor at AERE, Savar, Dhaka, Bangladesh. Structural studies of materials are being done by this technique to characterize materials crystallograpohically and magnetically. The micro-structural information obtainable by neutron scattering method is very essential for determining its technological applications. This technique is unique for understanding the magnetic behavior in magnetic materials. Ceramic, steel, electronic and electric industries can be benefited from this facility for improving their products and fabrication process. This instrument consists of a Popovicimonochromator with a large linear position sensitive detector array. The monochromator consists of nine blades of perfect single crystal of silicon with 6mm thickness each. The monochromator design was optimized to provide maximum flux on 3mm diameter cylindrical sample with a relatively flat angular dependence of resolution. Five different wave lengths can be selected by orienting the crystal at various angles. A sapphire filter was used before the primary collimator to minimize the first neutron. The detector assembly is composed of 15 linear position sensitive proportional counters placed at either 1.1 m or 1.6 m from the sample position and enclosed in a air pad supported high density polythene shield. Position sensing is obtained by charge division using 1-wide NIM position encoding modules (PEM). The PEMs communicate with the host computer via USB. The detector when placed at 1.1 m, subtends 30˚ (2θ) at each step and covers 120˚ in 4 steps. When the detector is placed at 1.6 m it subtends 20˚ at each step and covers 120˚ in 6 steps. The instrument supports both low and high temperature sample environment. The instrument supports both low and high temperature sample environment. The diffractometer is a state-of-the art technology

  14. Design of neutron beams for neutron capture therapy using a 300-kW slab TRIGA reactor

    SciTech Connect

    Liu, H.B.

    1995-03-01

    A design for a slab reactor to produce an epithermal neutron beam and a thermal neutron beam for use in neutron capture therapy (NCT) is described. A thin reactor with two large-area faces, a ``slab`` reactor, was planned using eighty-six 20% enriched TRIGA fuel elements and four B{sub 4}C control rods. Two neutron beams were designed: an epithermal neutron beam from one face and a thermal neutron beam from the other. The planned facility, based on this slab-reactor core with a maximum operating power of 300 kW, will provide an epithermal neutron beam of 1.8 {times} 10{sup 9} n{sub epi}/cm{sup 2}{center_dot}s intensity with low contamination by fast neutrons and gamma rays and a thermal neutron beam of 9.0 {times} 10{sup 9}n{sub th}/cm{sup 2}{center_dot}s intensity with low fast-neutron dose and gamma dose. Both neutron beams will be forward directed. Each beam can be turned on and off independently through its individual shutter. A complete NCT treatment using the designed epithermal or thermal neutron beam would take 30 or 20 min, respectively, under the condition of assuming 10{mu}g {sup 10}B/g in the blood. Such exposure times should be sufficiently short to maintain near-optimal target (e.g., {sup 10}B, {sup 157}Gd, and {sup 235}U) distribution in tumor versus normal tissues throughout the irradiation. With a low operating power of 300 kW, the heat generated in the core can be removed by natural convection through a pool of light water. The proposed design in this study could be constructed for a dedicated clinical NCT facility that would operate very safely.

  15. Automated system for neutron activation analysis determination of short lived isotopes at The DOW Chemical Company's TRIGA research reactor

    NASA Astrophysics Data System (ADS)

    Zieman, J. J.; Rigot, W. L.; Romick, J. D.; Quinn, T. J.; Kocher, C. W.

    1994-12-01

    An automated neutron activation analysis (NAA) system for the determination of short lived isotopes was constructed at The DOW Chemical Company's TRIGA Research Reactor in 1993. The NAA group of the Analytical Sciences Laboratory uses the reactor for thousands of analyses each year and therefore automation is important to achieve and maintain high throughput and precision (productivity). This project is complementary to automation of the long-lived counting facilities (see Romick et al., these Proceedings). Canberra/Nuclear Data Systems DEC-based software and electronics modules and an I/O mounting board are the basic commercial components. A Fortran program on a VAX computer controls I/O via ethernet to an Acquisition Interface Module (AIM). The AIM controls the γ spectrometer modules and is interfaced to a Remote Parallel Interface (RPI) module which controls the pneumatic transfer apparatus with TTL signals to the I/O mounting board. Near-infrared sensors are used to monitor key points in the transfer system. Spectra are acquired by a single HPGe detector mounted on a sliding rail to allow flexible and more reproducible counting geometries than with manual sample handling. The maximum sample size is 8 ml in a heat-sealed two dram vial. The sample vial is nested into a "rabbit" vial for irradiation which can be automatically removed prior to spectrum collection. The system was designed to be used by the reactor operator at the control console without the aid of an additional experimenter. Applications include the determination of selenium and silver in coal and water, fluorine in tetra-fluoro ethylene (TFE) coated membranes, aluminum and titanium in composite materials and trace fluorine in non-chlorinated cleaning solvents. Variable dead time software allows analysis for 77mSe despite high dead times from 16N encountered in samples.

  16. Evaluation of interprofessional education: lessons learned through the development and implementation of an interprofessional seminar on team communication for undergraduate health care students in Heidelberg – a project report

    PubMed Central

    Berger, Sarah; Mahler, Cornelia; Krug, Katja; Szecsenyi, Joachim; Schultz, Jobst-Hendrik

    2016-01-01

    Introduction: This project report describes the development, “piloting” and evaluation of an interprofessional seminar on team communication bringing together medical students and Interprofessional Health Care B.Sc. students at the Medical Faculty of Heidelberg University, Germany. Project Description: A five-member interprofessional team collaborated together on this project. Kolb’s experiential learning concept formed the theoretical foundation for the seminar, which explored three interprofessional competency areas: team work, communication and values/ethics. Evaluation for the purposes of quality assurance and future curricula development was conducted using two quantitative measures: descriptive analysis of a standardized course evaluation tool (EvaSys) ANOVA analysis of the German translation of the University of the West of England Interprofessional Questionnaire (UWE-IP-D). Results: The key finding from the standardized course evaluation was that the interprofessional seminars were rated more positively [M=2.11 (1 most positive and 5 most negative), SD=1, n=27] than the monoprofessional seminars [M=2.55, SD=0.98, n=90]. The key finding from the UWE-IP-D survey, comparing pre and post scores of the interprofessional (IP) (n=40) and monoprofessional (MP) groups (n=34), was that significant positive changes in mean scores for both groups towards communication, teamwork and interprofessional learning occurred. Conclusions: Lessons learnt included: a) recognising the benefit of being pragmatic when introducing interprofessional education initiatives, which enabled various logistical and attitudinal barriers to be overcome; b) quantitative evaluation of learning outcomes alone could not explain positive responses or potential influences of interprofessional aspects, which highlighted the need for a mixed methods approach, including qualitative methods, to enrich judgment formation on interprofessional educational outcomes. PMID:27280133

  17. Consistency of vitamin and/or mineral supplement use and demographic, lifestyle and health-status predictors: findings from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort.

    PubMed

    Li, Kuanrong; Kaaks, Rudolf; Linseisen, Jakob; Rohrmann, Sabine

    2010-10-01

    Cross-sectional studies suggest that dietary supplement use is associated with favourable demographic and lifestyle factors and certain health conditions. However, factors that affect the consistency of supplement use have not been investigated in prospective cohort studies. The aim of the present study was to seek baseline demographic, lifestyle and health-status predictors of subsequent consistent vitamin and/or mineral supplement use. A total of 8968 men and 10,672 women of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort, who answered the supplement-use questions in the baseline survey and two follow-up surveys, were categorised into three groups: consistent, inconsistent and never users. At baseline, 28.5 % of men and 38.6 % of women reported vitamin and/or mineral supplement use. After a median follow-up of 8.5 years, 14.6 % of men and 22.9 % of women were consistent users. During follow-up, 36.0 % of male and 26.6 % of female initial users stopped supplement use, whereas 27.8 % of male and 39.4 % of female initial non-users started supplement use. Women were more likely to be consistent users than men. Older age (≥ 50 years), lower BMI (< 25 kg/m2) and self-reported hyperlipidaemia were common predictors of consistent use for both sexes. Additional predictors included higher educational level for men, and being more physically active and higher lifetime alcohol consumption for women. Consistent users had the highest intake of dairy products, fish, fruits and vegetables, and wine but the lowest intake of total meat. We concluded that supplement use is a fairly unstable behaviour in free-living individuals. Individuals with a favourable lifestyle and healthier diet are more likely to show consistent supplementation. PMID:20441685

  18. Design, construction, and demonstration of a neutron beamline and a neutron imaging facility at a Mark-I TRIGA reactor

    NASA Astrophysics Data System (ADS)

    Craft, Aaron E.

    The fleet of research and training reactors is aging, and no new research reactors are planned in the United States. Thus, there is a need to expand the capabilities of existing reactors to meet users' needs. While many research reactors have beam port facilities, the original design of the United States Geological Survey TRIGA Reactor (GSTR) did not include beam ports. The MInes NEutron Radiography (MINER) facility developed by this thesis and installed at the GSTR provides new capabilities for both researchers and students at the Colorado School of Mines. The facility consists of a number of components, including a neutron beamline and beamstop, an optical table, an experimental enclosure and associated interlocks, a computer control system, a multi-channel plate imaging detector, and the associated electronics. The neutron beam source location, determined through Monte Carlo modeling, provides the best mixture of high neutron flux, high thermal neutron content, and low gamma radiation content. A Monte Carlo n-Particle (MCNP) model of the neutron beam provides researchers with a tool for designing experiments before placing objects in the neutron beam. Experimental multi-foil activation results, compared to calculated multi-foil activation results, verify the model. The MCNP model predicts a neutron beamline flux of 2.2*106 +/- 6.4*105 n/cm2-s based on a source particle rate determined from the foil activation experiments when the reactor is operating at a power of 950 kWt with the beam shutter fully open. The average cadmium ratio of the beamline is 7.4, and the L/D of the neutron beam is approximately 200+/-10. Radiographs of a sensitivity indicator taken using both the digital detector and the transfer foil method provide one demonstration of the radiographic capabilities of the new facility. Calibration fuel pins manufactured using copper and stainless steel surrogate fuel pellets provide additional specimens for demonstration of the new facility and offer a

  19. GEANT4 used for neutron beam design of a neutron imaging facility at TRIGA reactor in Morocco

    NASA Astrophysics Data System (ADS)

    Ouardi, A.; Machmach, A.; Alami, R.; Bensitel, A.; Hommada, A.

    2011-09-01

    Neutron imaging has a broad scope of applications and has played a pivotal role in visualizing and quantifying hydrogenous masses in metallic matrices. The field continues to expand into new applications with the installation of new neutron imaging facilities. In this scope, a neutron imaging facility for computed tomography and real-time neutron radiography is currently being developed around 2.0MW TRIGA MARK-II reactor at Maamora Nuclear Research Center in Morocco (Reuscher et al., 1990 [1]; de Menezes et al., 2003 [2]; Deinert et al., 2005 [3]). The neutron imaging facility consists of neutron collimator, real-time neutron imaging system and imaging process systems. In order to reduce the gamma-ray content in the neutron beam, the tangential channel was selected. For power of 250 kW, the corresponding thermal neutron flux measured at the inlet of the tangential channel is around 3×10 11 ncm 2/s. This facility will be based on a conical neutron collimator with two circular diaphragms with diameters of 4 and 2 cm corresponding to L/D-ratio of 165 and 325, respectively. These diaphragms' sizes allow reaching a compromise between good flux and efficient L/D-ratio. Convergent-divergent collimator geometry has been adopted. The beam line consists of a gamma filter, fast neutrons filter, neutron moderator, neutron and gamma shutters, biological shielding around the collimator and several stages of neutron collimator. Monte Carlo calculations by a fully 3D numerical code GEANT4 were used to design the neutron beam line ( http://www.info.cern.ch/asd/geant4/geant4.html[4]). To enhance the neutron thermal beam in terms of quality, several materials, mainly bismuth (Bi) and sapphire (Al 2O 3) were examined as gamma and neutron filters respectively. The GEANT4 simulations showed that the gamma and epithermal and fast neutron could be filtered using the bismuth (Bi) and sapphire (Al 2O 3) filters, respectively. To get a good cadmium ratio, GEANT 4 simulations were used to

  20. The Design and Construction of a Cold Neutron Source for Use in the Cornell University Triga Reactor

    NASA Astrophysics Data System (ADS)

    Young, Lydia Jane

    A cold neutron source has been designed and constructed for insertion into the 6"-radial beam port of the Cornell University TRIGA reactor for use with a neutron guide tube system. The main differences between this cold source and other existing sources are the use of heat conduction as the method of cooling and the use of mesitylene (1,3,5 -trimethylbenzene; melting point, 228(DEGREES)K; boiling point, 437(DEGREES)K) as the moderating material. This thesis describes the design and construction details of the cold neutron source, discusses its safety aspects, and presents its cryogenic performance curves and also the results of a test of its neutron moderating ability. A closed-cycle helium gas refrigerator, located outside the reactor shielding, cools the 500 cm('3) moderator chamber and its surrounding heat shield by heat conduction through two meters of copper and rod tubing. Moderator temperatures of 23 (+OR-) 3(DEGREES)K have been achieved. Mesitylene, a hydrocarbon, is an effective cold moderator because even at low temperatures the weakly hindered rotational motions of its methyl groups enable the absorption of small amounts of energy ((LESSTHEQ) 0.005 eV) from neutrons. The use of mesitylene simplifies the cold source design because it is a liquid at room temperature and thus, the usual design safeguards required for sources using gaseous moderators are not necessary. Moreover, the flammability of mesitylene is much smaller than that of hydrogen and methane, which are the commonly used cold moderators. A method of transferring and handling the mesitylene, a carcinogen, was devised to ensure minimal contact with this substance. To test the neutron moderating ability of the cold neutron source, an out-of-reactor neutron transmission experiment was performed with the moderator chamber first at room temperature and then at about 23(DEGREES)K. The results indicate that the neutron energy spectrum is strongly shifted to lower energies when the chamber is cold

  1. Material Sample Collection with Tritium and Gamma Analyses at the University of Illinois's Nuclear Research Laboratory TRIGA Nuclear Research Reactor

    SciTech Connect

    Charters, G.; Aggarwal, S.

    2006-07-01

    The University of Illinois in Champaign-Urbana has an Advanced TRIGA reactor facility which was built in 1960 and operated until August 1998. The facility was shutdown for a variety of reasons, primarily due to a lack of usage by the host institution. In 1998 the reactor went into SAFSTOR and finally shipped its fuel in 2004. At the present time a site characterization and decommissioning plan are in process and hope to be submitted to the NRC in early 2006. The facility had to be fully characterized and part of this characterization involved the collection and analysis of samples. This included various solid media such as, concrete, graphite, metals, and sub-slab surface soils for immediate analysis of Activation and Tritium contamination well below the easily measured surfaces. This detailed facility investigation provided a case to eliminate historical unknowns, increasing the confidence for the segregation and packaging of high specific activity Low Level Radwaste (LLRW), from which a strategy of 'surgical-demolition' and segregation could be derived thus maximizing the volumes of 'clean material'. Performing quantitative volumetric concrete or metal radio-analyses safer and faster (without lab intervention) was a key objective of this dynamic characterization approach. Currently, concrete core bores are shipped to certified laboratories where the concrete residue is run through a battery of tests to determine the contaminants. The existing core boring operation volatilises or washes out some of the contaminants (like tritium) and oftentimes cross-contaminates the are a around the core bore site. The volatilization of the contaminants can lead to airborne problems in the immediate vicinity of the core bore. Cross-contamination can increase the contamination area and thereby increase the amount of waste generated that needs to be treated and stabilized before disposal. The goal was to avoid those field activities that could cause this type of release. Therefore

  2. Dose calculation in biological samples in a mixed neutron-gamma field at the TRIGA reactor of the University of Mainz.

    PubMed

    Schmitz, Tobias; Blaickner, Matthias; Schütz, Christian; Wiehl, Norbert; Kratz, Jens V; Bassler, Niels; Holzscheiter, Michael H; Palmans, Hugo; Sharpe, Peter; Otto, Gerd; Hampel, Gabriele

    2010-10-01

    To establish Boron Neutron Capture Therapy (BNCT) for non-resectable liver metastases and for in vitro experiments at the TRIGA Mark II reactor at the University of Mainz, Germany, it is necessary to have a reliable dose monitoring system. The in vitro experiments are used to determine the relative biological effectiveness (RBE) of liver and cancer cells in our mixed neutron and gamma field. We work with alanine detectors in combination with Monte Carlo simulations, where we can measure and characterize the dose. To verify our calculations we perform neutron flux measurements using gold foil activation and pin-diodes. Material and methods. When L-α-alanine is irradiated with ionizing radiation, it forms a stable radical which can be detected by electron spin resonance (ESR) spectroscopy. The value of the ESR signal correlates to the amount of absorbed dose. The dose for each pellet is calculated using FLUKA, a multipurpose Monte Carlo transport code. The pin-diode is augmented by a lithium fluoride foil. This foil converts the neutrons into alpha and tritium particles which are products of the (7)Li(n,α)(3)H-reaction. These particles are detected by the diode and their amount correlates to the neutron fluence directly. Results and discussion. Gold foil activation and the pin-diode are reliable fluence measurement systems for the TRIGA reactor, Mainz. Alanine dosimetry of the photon field and charged particle field from secondary reactions can in principle be carried out in combination with MC-calculations for mixed radiation fields and the Hansen & Olsen alanine detector response model. With the acquired data about the background dose and charged particle spectrum, and with the acquired information of the neutron flux, we are capable of calculating the dose to the tissue. Conclusion. Monte Carlo simulation of the mixed neutron and gamma field of the TRIGA Mainz is possible in order to characterize the neutron behavior in the thermal column. Currently we also

  3. Thermal-Hydraulic Analysis of the 3-MW TRIGA MARK-II Research Reactor Under Steady-State and Transient Conditions

    SciTech Connect

    Huda, M.Q.; Bhuiyan, S.I.; Chakrobortty, T.K.; Sarker, M.M.; Mondal, M.A.W

    2001-07-15

    Important thermal-hydraulic parameters of the 3-MW TRIGA MARK-II research reactor operating under both steady-state and transient conditions are reported. Neutronic analyses were performed by using the CITATION diffusion code and the MCNP4B2 Monte Carlo code. The output of CITATION and MCNP4B2 were input to the PARET thermal-hydraulic code to study the steady-state and transient thermal-hydraulic behavior of the reactor. To benchmark the PARET model, data were obtained from different measurements performed by thermocouples in the instrumented fuel (IF) rod during the steady-state operation both under forced- and natural-convection mode and compared with the calculation. The mass flow rates needed for input to PARET were taken from the Final Safety Analysis Report for a downward forced coolant flow equivalent to 3500 gal/min. For natural convection cooling of the reactor, the mass flow rate was generated using the NCTRIGA code. Peak fuel temperatures measured by the thermocouples in the IF rods at different power levels of the TRIGA core were compared with the values calculated by PARET. The axial distribution of the temperatures of the fuel centerline, fuel surface, and the cladding surface in the hot channel were calculated for the reactor operating at the full-power level. Fuel surface heat flux and heat transfer coefficients for the hot channel were also calculated for the reactor operating at the full-power level. The investigated results were found to be in good agreement with the experimental and operational values. The testing of the PARET model calculations through benchmarking the available TRIGA experimental and operational data for pulse-mode operations showed that PARET can successfully be used to analyze the transient behavior of the reactor. Major transient parameters, such as peak power and prompt energy released after pulse, full-width at half-maximum of pulse peak, and maximum fuel centerline temperatures for different fuel elements at different

  4. Measurement of DNA damage induced by irradiation with gamma-rays from a TRIGA Mark II research reactor in human cells using Fast Micromethod.

    PubMed

    Hassanein, Hamdy; Müller, Claudia I; Schlösser, Dietmar; Kratz, Karl-Ludwig; Senyuk, Olga F; Schröder, Heinz C

    2002-06-01

    The Fast Micromethod is a novel quick and convenient microplate assay for determination of DNA single-strand breaks. This method measures the rate of unwinding of cellular DNA upon exposure to alkaline conditions using a fluorescent dye which preferentially binds to double-stranded DNA. Here we applied this method to determine the levels of DNA single-strand breaks in HeLa cells induced by y-irradiation deriving from fission isotopes and activation products at the TRIGA Mark II research reactor in Mainz. An increased strand scission factor (SSF) value, which is indicative for DNA damage, was found at doses of 1 Gy and higher. A similar increase in SSF value, which further increased in a dose-dependent manner, was found in human peripheral blood mononuclear cells after irradiation with 6 MV X-rays from a linear accelerator to give a total exposure of 0.5 to 10 Gy. PMID:12064446

  5. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons: I. Irradiation of human blood samples in the "dry cell" of the TRIGA Mark II nuclear reactor.

    PubMed

    Fajgelj, A; Lakoski, A; Horvat, D; Remec, I; Skrk, J; Stegnar, P

    1991-11-01

    A set-up for irradiation of biological samples in the TRIGA Mark II research reactor in Ljubljana is described. Threshold activation detectors were used for characterisation of the neutron flux, and the accompanying gamma dose was measured by TLDs. Human peripheral blood samples were irradiated "in vitro" and biological effects evaluated according to the unstable chromosomal aberrations induced. Biological effects of two types of cultivation of irradiated blood samples, the first immediately after irradiation and the second after 96 h storage, were studied. A significant difference in the incidence of chromosomal aberrations between these two types of samples was obtained, while our dose-response curve fitting coefficients alpha 1 = (7.71 +/- 0.09) x 10(-2) Gy-1 (immediate cultivation) and alpha 2 = (11.03 +/- 0.08) x 10(-2) Gy-1 (96 h delayed cultivation) are in both cases lower than could be found in the literature. PMID:1962281

  6. Preliminary TRIGA fuel burn-up evaluation by means of Monte Carlo code and computation based on total energy released during reactor operation

    SciTech Connect

    Borio Di Tigliole, A.; Bruni, J.; Panza, F.; Alloni, D.; Cagnazzo, M.; Magrotti, G.; Manera, S.; Prata, M.; Salvini, A.; Chiesa, D.; Clemenza, M.; Pattavina, L.; Previtali, E.; Sisti, M.; Cammi, A.

    2012-07-01

    Aim of this work was to perform a rough preliminary evaluation of the burn-up of the fuel of TRIGA Mark II research reactor of the Applied Nuclear Energy Laboratory (LENA) of the Univ. of Pavia. In order to achieve this goal a computation of the neutron flux density in each fuel element was performed by means of Monte Carlo code MCNP (Version 4C). The results of the simulations were used to calculate the effective cross sections (fission and capture) inside fuel and, at the end, to evaluate the burn-up and the uranium consumption in each fuel element. The evaluation, showed a fair agreement with the computation for fuel burn-up based on the total energy released during reactor operation. (authors)

  7. Validation of absolute axial neutron flux distribution calculations with MCNP with 197Au(n,γ)198Au reaction rate distribution measurements at the JSI TRIGA Mark II reactor.

    PubMed

    Radulović, Vladimir; Štancar, Žiga; Snoj, Luka; Trkov, Andrej

    2014-02-01

    The calculation of axial neutron flux distributions with the MCNP code at the JSI TRIGA Mark II reactor has been validated with experimental measurements of the (197)Au(n,γ)(198)Au reaction rate. The calculated absolute reaction rate values, scaled according to the reactor power and corrected for the flux redistribution effect, are in good agreement with the experimental results. The effect of different cross-section libraries on the calculations has been investigated and shown to be minor. PMID:24316530

  8. Dose estimation in B16 tumour bearing mice for future irradiation in the thermal column of the TRIGA reactor after B/Gd/LDL adduct infusion.

    PubMed

    Protti, N; Ballarini, F; Bortolussi, S; Bruschi, P; Stella, S; Geninatti, S; Alberti, D; Aime, S; Altieri, S

    2011-12-01

    To test the efficacy of a new (10)B-vector compound, the B/Gd/LDL adduct synthesised at Torino University, in vivo irradiations of murine tumours are in progress at the TRIGA Mark II reactor of the Pavia University. A localised B16 melanoma tumour is generated in C57BL/6 mice and subsequently infused with the adduct. During the irradiation, the mouse will be put in a shield to protect the whole body except the tumour in the back-neck area. To optimise the treatment set-up, MCNP simulations were performed. A very simplified mouse model was built using MCNP geometry capabilities, as well as the geometry of the shield made of 99% (10)B enriched boric acid. A hole in the shield is foreseen in correspondence of the back-neck region. Many configurations of the shield were tested in terms of neutron flux, dose distribution and mean induced activity in the tumour region and in the radiosensitive organs of the mouse. In the final set-up, up to five mice can be treated simultaneously in the reactor thermal column and the neutron fluence in the tumour region for 10 min of irradiation is of about 5×10(12) cm(-2). PMID:21459587

  9. Calculations of dose distributions in the lungs of a rat model irradiated in the thermal column of the TRIGA reactor in Pavia.

    PubMed

    Protti, N; Bortolussi, S; Stella, S; Gadan, M A; De Bari, A; Ballarini, F; Bruschi, P; Ferrari, C; Clerici, A M; Zonta, C; Bakeine, J G; Dionigi, P; Zonta, A; Altieri, S

    2009-07-01

    To test the possibility to apply boron neutron capture therapy (BNCT) to lung tumors, some rats are planned to be irradiated in the thermal column of the TRIGA reactor of the University of Pavia. Before the irradiation, lung metastases will be induced in BDIX rats, which will be subsequently infused with boronophenylalanine (BPA). During the irradiation, the rats will be positioned in a box designed to shield the whole animal except the thorax area. In order to optimize the irradiation set-up and to design a suitable shielding box, a set of calculations were performed with the MCNP Monte Carlo transport code. A rat model was constructed using the MCNP geometry capabilities and was positioned in a box with walls filled with lithium carbonate. A window was opened in front of the lung region. Different shapes of the holder and of the window were tested and analyzed in terms of the dose distribution obtained in the lungs and of the dose absorbed by the radiosensitive organs in the rat. The best configuration of the holder ensures an almost uniform thermal neutron flux inside the lungs (Phi(max)/Phi(min)=1.5), an irradiation time about 10 min long, to deliver at least 40 Gy(w) to the tumor, a mean lung dose of 5.9+/-0.4 Gy(w), and doses absorbed by all the other healthy tissues below the tolerance limits. PMID:19406647

  10. Analytical analyses of startup measurements associated with the first use of LEU fuel in Romania`s 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.; Snelgrove, J.L.; Ciocanescu, M.

    1992-12-01

    The 14-MW TRIGA steady state reactor (SSR) is located in Pitesti, Romania. Beginning with an HEU core (10 wt% U), the reactor first went critical in November 1979 but was shut down ten years later because of insufficient excess reactivity. Last November the Institute for Nuclear Research (INR), which operates the SSR, received from the ANL RERTR program a shipment of 125 LEU pins fabricated by General Atomics and of the same geometry as the original fuel but with an enrichment of 19.7% 235U and a loading of 45 wt% U. Using 100 of these pins, four LEU clusters, each containing a 5 x 5 square array of fuel rods, were assembled. These four LEU clusters replaced the four most highly burned HEU elements in the SSR. The reactor resumed operations last February with a 35-element mixed HEU/LEU core configuration. In preparation for full power operation of the SSR with this mixed HEU/LEU core, a number of measurements were made. These included control rod calibrations, excess reactivity determinations, worths of experiment facilities, reaction rate distributions, and themocouple measurements of fuel temperatures as a function of reactor power. This paper deals with a comparison of some of these measured reactor parameters with corresponding analytical calculations.

  11. Measurements of miniature ionization chamber currents in the JSI TRIGA Mark II reactor demonstrate the importance of the delayed contribution to the photon field in nuclear reactors

    NASA Astrophysics Data System (ADS)

    Radulović, Vladimir; Fourmentel, Damien; Barbot, Loïc; Villard, Jean-François; Kaiba, Tanja; Gašper, Žerovnik; Snoj, Luka

    2015-12-01

    The characterization of experimental locations of a research nuclear reactor implies the determination of neutron and photon flux levels within, with the best achievable accuracy. In nuclear reactors, photon fluxes are commonly calculated by Monte Carlo simulations but rarely measured on-line. In this context, experiments were conducted with a miniature gas ionization chamber (MIC) based on miniature fission chamber mechanical parts, recently developed by the CEA (French Atomic Energy and Alternative Energies Commission) irradiated in the core of the Jožef Stefan Institute TRIGA Mark II reactor in Ljubljana, Slovenia. The aim of the study was to compare the measured MIC currents with calculated currents based on simulations with the MCNP6 code. A discrepancy of around 50% was observed between the measured and the calculated currents; in the latter taking into consideration only the prompt photon field. Further experimental measurements of MIC currents following reactor SCRAMs (reactor shutdown with rapid insertions of control rods) provide evidence that over 30% of the total measured signal is due to the delayed photon field, originating from fission and activation products, which are untreated in the calculations. In the comparison between the measured and calculated values, these findings imply an overall discrepancy of less than 20% of the total signal which is still unexplained.

  12. Criticality and Safety Parameter Studies of a 3-MW TRIGA MARK-II Research Reactor and Validation of the Generated Cross-Section Library and Computational Method

    SciTech Connect

    Bhuiyan, S.I.; Mondal, M.A.W.; Sarker, M.M.; Rahman, M.; Shahdatullah, M.S.; Huda, M.Q.; Chakrobortty, T.K.; Khan, M.J.H

    2000-05-15

    This study deals with the analysis of some neutronics and safety parameters of the current core of a 3-MW TRIGA MARK-II research reactor and validation of the generated macroscopic cross-section library and calculational techniques by benchmarking with experimental, operational, and available Safety Analysis Report (SAR) values. The overall strategy is: (a) generation of the problem-dependent cross-section library from basic Evaluated Nuclear Data Files such as ENDF/B-VI and JENDL-3.2 with NJOY94.10+, (b) use of the WIMSD-5 package to generate a few-group neutron macroscopic cross section for all of the materials in the core and its immediate neighborhood, (c) use the three-dimensional CITATION code to perform the global analysis of the core, and (d) checking of the validity of the CITATION diffusion code with the MCNP4B2 Monte Carlo code. The ultimate objective is to establish methods for reshuffling the current core configuration to upgrade the thermal flux at irradiation locations for increased isotope production. The computational methods, tools and techniques, customization of cross-section libraries, various models for cells and supercells, and many associated utilities are standardized and established/validated for the overall neutronic analysis. The excess reactivity, neutron flux, power distribution, power peaking factors, determination of the hot spot, and fuel temperature reactivity coefficients {alpha}{sub f} in the temperature range of 45 to 1000 deg. C are studied. All the analyses are performed using the 4- and 7-group libraries of the macroscopic cross sections generated from the 69-group WIMSD-5 library. The 7-group calculations yield comparatively better agreement with the experimental value of k{sub eff} and the other core parameters. The CITATION test runs using different cross-section sets based on the different models applied in the WIMSD-5 calculations show a strong influence of those models on the final integral parameter. Some of the cells

  13. Test and evaluate the tri-gas low-Btu coal-gasification process. Final report, October 21, 1977-October 31, 1980

    SciTech Connect

    Zabetakis, M.G.

    1980-12-01

    This report describes the continuation of work done to develop the BCR TRI-GAS multiple fluidized-bed gasification process. The objective is the gasification of all ranks of coals with the only product being a clean, low-Btu fuel gas. Design and construction of a 100 lb/h process and equipment development unit (PEDU) was completed on the previous contract. The process consists of three fluid-bed reactors in series, each having a specific function: Stage 1 - pretreatment; Stage 2- - gasification; Stage 3 - maximization of carbon utilization. Under the present contract, 59 PEDU tests have been conducted. A number of these were single-stage tests, mostly in Stage 1; however, integrated PEDU tests were conducted with a western coal (Rosebud) and two eastern coals (Illinois No. 6 and Pittsburgh seam). Both Rosebud and Pittsburgh seam coals were gasified with the PEDU operating in the design mode. Operation with Illinois No. 6 seam coal was also very promising; however, time limitations precluded further testing with this coal. One of the crucial tasks was to operate the Stage 1 reactor to pretreat and devolatilize caking coals. By adding a small amount of air to the fluidizing gas, the caking properties of the coal can be eliminated. However, it was also desirable to release a high percentage of the volatile matter from the coal in this vessel. To accomplish this, the reactor had to be operated above the agglomerating temperature of caking coals. By maintaining a low ratio of fresh to treated coal, this objective was achieved. Both Illinois No. 6 and Pittsburgh seam coals were treated at temperatures of 800 to 900 F without agglomerating in the vessel.

  14. Testing WIMS-D4M cross sections and the ANL ENDF/B-V 69 group library. Results from global diffusion and Monte Carlo calculations compared with measurements in the Romanian 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.

    1993-12-31

    The WIMS-D4 code has been modified (WIMS-D4M) to produce microscopic isotopic cross sections in ISOTXS format for use in diffusion and transport calculations. Beginning with 69-group libraries based on ENDF/B-V data, numerous cell calculations have been made to prepare a set of broad group cross sections for use in diffusion calculations. Global calculations have been made for two control rod states of the Romanian steady state TRIGA reactor with 29 fresh HEU fuel clusters. Detailed Monte Carlo calculations also have been performed for the same reactor configurations using data based on ENDF/B-V. Results from these global calculations are compared with each other and with the measured excess reactivities. Although region-averaged macroscopic principal cross sections obtained from WIMS-D4M are in good agreement with the corresponding Monte Carlo values, problems exist with the high energy (E > 10 keV) microscopic hydrogen transport cross sections.

  15. Heidelberg Spectralis Optical Coherence Tomography Angiography: Technical Aspects.

    PubMed

    Coscas, Gabriel; Lupidi, Marco; Coscas, Florence

    2016-01-01

    Optical coherence tomography angiography (OCT-A) is a promising new method for visualizing the retinal vasculature and choroidal vascular layers in the macular area and provides depth-resolved functional information on blood flow in these vessels. OCT-A is based on the concept that in a static eye the only moving structure in the fundus of the eye is blood flowing through the vessels. Contrast is generated based on the difference between moving cells in the vasculature and the static surrounding tissue. Artifacts can arise due to scan positioning errors caused by normal ocular microsaccades. In order to avoid artifacts, a sequence of OCT B-scans in the exact same retinal location must be taken to detect flow. Active eye-tracking (TruTrack™) using the simultaneous acquisition of fundus and optical coherence tomography (OCT) images presents a very reliable method of acquiring OCT volume scans without motion artifacts and helps significantly improve signal-to-noise ratio. This system also allows the use of a full spectrum amplitude decorrelation algorithm that produces clear differentiation between blood flow and static tissue without sacrificing the axial resolution of OCT images. Accuracy in layer segmentation, which requires high-resolution OCT B-scans, is crucial for producing reliable OCT-A images. This can be achieved through automated or manual layer segmentation. During OCT scan acquisition, the effect of axial motion (e.g. a patient moving towards the camera) is compensated for by geometric alignment of successive B-scans before analyzing temporal changes. PMID:27022921

  16. Deployment of a three-dimensional array of Micro-Pocket Fission Detector triads (MPFD3) for real-time, in-core neutron flux measurements in the Kansas State University TRIGA Mark-II Nuclear Reactor

    NASA Astrophysics Data System (ADS)

    Ohmes, Martin Francis

    A Micro-Pocket Fission Detector (MPFD) is a miniaturized type of fission chamber developed for use inside a nuclear reactor. Their unique design allows them to be located between or even inside fuel pins while being built from materials which give them an operational lifetime comparable to or exceeding the life of the fuel. While other types of neutron detectors have been made for use inside a nuclear reactor, the MPFD is the first neutron detector which can survive sustained use inside a nuclear reactor while providing a real-time measurement of the neutron flux. This dissertation covers the deployment of MPFDs as a large three-dimensional array inside the Kansas State University TRIGA Mark-II Nuclear Reactor for real-time neutron flux measurements. This entails advancements in the design, construction, and packaging of the Micro-Pocket Fission Detector Triads with incorporated Thermocouple, or MPFD3-T. Specialized electronics and software also had to be designed and built in order to make a functional system capable of collecting real-time data from up to 60 MPFD3-Ts, or 180 individual MPFDs and 60 thermocouples. Design of the electronics required the development of detailed simulations and analysis for determining the theoretical response of the detectors and determination of their size. The results of this research shows that MPFDs can operate for extended times inside a nuclear reactor and can be utilized toward the use as distributed neutron detector arrays for advanced reactor control systems and power mapping. These functions are critical for continued gains in efficiency of nuclear power reactors while also improving safety through relatively inexpensive redundancy.

  17. Sitzungsberichte der Heidelberger Akademie der Wissenschaften> " Jahrgang 1990 Sitzungsber.Heidelberg 90 " "Gott hat die Natur einfältig gemacht, sie aber suchen viel Künste"

    NASA Astrophysics Data System (ADS)

    Zehe, Horst

    Der Aufsatz demonstriert anhand ausgiebig kommentierter zeitgenössischer Zeugnisse Goethes Reaktion auf die Arbeiten Fraunhofers, insbesondere auf die Entdeckung der dunklen Linien im Sonnenspektrum. Den Fehlurteilen Goethes werden dabei die Urteile zeitgenössischer Physiker wie Chladni und J.F.W. Herschel gegenübergestellt. Bislang noch ungedruckte Dokumente aus dem Weimarer Goethe- und Schiller-Archiv belegen, daß sich Goethe nicht nur literarisch mit Fraunhofer beschäftigte, sondern daß er auch dessen Versuche mit Hilfe des Jenaer Universitätsmechanikers Körner getreulich zu wiederholen suchte.

  18. Genotypic and phenotypic characterization of Salmonella Heidelberg and Kentucky isolates recovered from broiler chicks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foodborne pathogens are constantly adapting to circumvent intervention strategies. The ability to detect and overcome these adaptations is critical to ensure a safe food supply. We determined genotypic and/or phenotypic differences between Salmonella recovered from broiler chicks after comingling wi...

  19. Trace elemental analysis of bituminuos coals using the Heidelberg proton microprobe

    USGS Publications Warehouse

    Chen, J.R.; Kneis, H.; Martin, B.; Nobiling, R.; Traxel, K.; Chao, E.C.T.; Minkin, J.A.

    1981-01-01

    Trace elements in coal can occur as components of either the organic constituents (macerals) or the inorganic constituents (minerals). Studies of the concentrations and distribution of the trace elements are vital to understanding the geochemical millieu in which the coal was formed and in evaluating the attempts to recover rare but technologically valuable metals. In addition, information on the trace element concentrations is important in predicting the environmental impact of burning particular coals, as many countries move toward greater utilization of coal reserves for energy production. Traditionally, the optical and the electron microscopes and more recently the electron microprobe have been used in studying the components of coal. The proton-induced X-ray emission (PIXE) microprobe offers a new complementary approach with an order of magnitude or more better minimum detection limit. We present the first measurements with a PIXE microprobe of the trace element concentrations of bituminous coal samples. Elemental analyses of the coal macerals-vitrinite, exinite, and inertinite-are discussed for three coal samples from the Eastern U.S.A., three samples from the Western U.S.A., and one sample from the Peoples Republic of China. ?? 1981.

  20. Improving University Teaching. Proceedings. International Conference (12th, Heidelberg, Germany, July 15-18, 1986).

    ERIC Educational Resources Information Center

    Maryland Univ., College Park. Univ. Coll.

    Proceedings of the twelfth international conference on improving university teaching are presented. Theme presentations and authors include: "Distance Education: The Promise and the Confusion!" (Allan F. Hershfield); "Distance Education: The 'New Frontier' of Learning?" (Kevin C. Smith); "Teacher Training: A Challenge to the University View of…

  1. United States Domestic Research Reactor Infrastrucutre TRIGA Reactor Fuel Support

    SciTech Connect

    Douglas Morrell

    2011-03-01

    The United State Domestic Research Reactor Infrastructure Program at the Idaho National Laboratory manages and provides project management, technical, quality engineering, quality inspection and nuclear material support for the United States Department of Energy sponsored University Reactor Fuels Program. This program provides fresh, unirradiated nuclear fuel to Domestic University Research Reactor Facilities and is responsible for the return of the DOE-owned, irradiated nuclear fuel over the life of the program. This presentation will introduce the program management team, the universities supported by the program, the status of the program and focus on the return process of irradiated nuclear fuel for long term storage at DOE managed receipt facilities. It will include lessons learned from research reactor facilities that have successfully shipped spent fuel elements to DOE receipt facilities.

  2. Failure of TRIGA fuel cladding at the Berkeley research reactor

    SciTech Connect

    Denton, Michael M.; Lim, Tek H.

    1986-07-01

    Following a long maintenance shutdown during which a fission chamber was refurbished and a compensated ion chamber replaced, concentrations of radioisotopes were detected in the reactor-room air on a Constant (CAM) after two and a half hours of full-power operation. Following test lead to identification of three fission-product gasses in the reactor room air: Kr{sup 85m}, Kr{sup 87} , and Kr{sup 88} . Conservative estimates indicated the maximum concentrations of all fission gasses to be about 1.1x10{sup -8} {mu}Ci/ml with a total release of less than 1 mCi. It was concluded that the gasses come from a leaking fuel element. Three old, instrumented elements with defective thermocouples were removed first and the reactor was tested at full-power. No abnormal activities were detected during or following the operation. Each of the suspected fuel elements are instrumented with leadout tubes extending 15 feet to above the pool surface. This suggests some possible causes for the cladding failure. First, flexing due to daily movement of the core could have weakened the tube/cladding connection. Secondly, the cladding itself may have been damaged during maintenance procedures requiring removal of the elements or repositioning of the leadout tubes.

  3. Physics study of the TRADE : TRIGA accelerator driven experiment.

    SciTech Connect

    Naberejnev, D.; Imel, G.; Palmiotti, G.; Salvatores, M.

    2004-01-13

    This report deals with the validation of an ADS dynamic behavior through the TRADE program. We first describe the motivations behind the TRADE project. This includes the types of ADS experiments to be performed and their necessity, beam trips issues, representativity of the experiment, and steps to be taken in the validation procedure. Then we perform the characterization of the TRADE core using deterministic methods. The general core description is given. A number of results related to the core criticality and modeling with different geometries are presented. Finally we report the experimental results of the recent critical measurements including the control rod calibration, determination of the critical configurations and fluxes in the core.

  4. Sitzungsberichte der Heidelberger Akademie der Wissenschaften¬Jahrgang 1990 Sitzungsber.Heidelberg 90¬"Gott hat die Natur einfältig gemacht, sie aber suchen viel Künste"

    NASA Astrophysics Data System (ADS)

    Zehe, Horst

    Der Aufsatz demonstriert anhand ausgiebig kommentierter zeitgenössischer Zeugnisse Goethes Reaktion auf die Arbeiten Fraunhofers, insbesondere auf die Entdeckung der dunklen Linien im Sonnenspektrum. Den Fehlurteilen Goethes werden dabei die Urteile zeitgenössischer Physiker wie Chladni und J.F.W. Herschel gegenübergestellt. Bislang noch ungedruckte Dokumente aus dem Weimarer Goethe- und Schiller-Archiv belegen, daß sich Goethe nicht nur literarisch mit Fraunhofer beschäftigte, sondern daß er auch dessen Versuche mit Hilfe des Jenaer Universitätsmechanikers Körner getreulich zu wiederholen suchte.

  5. Tel Aviv-Heidelberg three-generation offspring study: Genetic determinants of apolipoprotein A1 and apolipoprotein B

    SciTech Connect

    Livshits, G.; Graff, E.; Brunner, D.

    1995-07-03

    The contribution of major gene and multifactorial effects on variation of plasma apolipoproteins A1 and B has been tested in a large sample of population-based Israeli pedigrees. Our most parsimonious and best fitting model for both apolipoproteins is consistent with Mendelian transmissibility, with significant contribution of major genes (with 2 alleles recessive and dominant within each locus) and polygenes, but neglects effects of common sib environment as well as related intergeneration differences in polygenic effects. Total genetic effects explain 71 and 58% of phenotypic variance of APO-A1 and APO-B levels. The major genes account for about 44 and 32% of the variance in APO-A1 and APO-B, respectively, and the frequency of the recessive alleles determining the high level of apolipoproteins under the study in the Israeli population is in the vicinity of 40% at each locus. 27 refs, 1 fig., 4 tabs.

  6. First atomic physics experiments with cooled stored ion beams at the Heidelberg heavy-ion ring TSR

    SciTech Connect

    Wolf, A.; Balykin, V.; Baumann, W.; Berger, J.; Bisoffi, G.; Blatt, P.; Blum, M.; Faulstich, A.; Friedrich, A.; Gerhard, M.; Geyer, C.; Grieser, M.; Grieser, R.; Habs, D.; Heyng, H.W.; Hochadel, B.; Holzer, B.; Huber, G.; Jaeschke, E.; Jung, M.; Karafillidis, A.; Kilgus, G.; Klein, R.; Kraemer, D.; Krause, P.; Krieg, M.; Kuehl, T.; Matl, K.; Mueller, A.; Music, M.; Neumann, R.; Neureither, G.; Ott, W.; Petrich, W.; Povh, B.; Repnow, R.; Schroeder, S.; Schuch, R.; Schwalm, D.; Sigray, P.; Steck, M.; Stokstad, R.; Szmola, E.; Wagner, M.; Wanner, B.; Welti, K.; Zwickler, S. Max-Planck-Institut fuer Kernphysik, Heidelberg Manne Siegbahn Institute , Stockholm Institut fuer Kernphysik, Universitaet Giessen, Institut fuer Physik, Universitaet Mainz Gesellschaft fuer Schwerionenforschung , Darmstadt (Fed

    1990-06-01

    An overview of atomic physics experiments at the heavy ion Test Storage Ring (TSR) is given. Highly charged ions up to fully stripped silicon have been stored at energies between 4 and 12 MeV/u. The enhancement of the beam intensity by stacking, the beam lifetime, and electron cooling of these ion beams are discussed. Radiative and state-selective dielectronic recombination rates of hydrogen-like oxygen ions with free electrons from the electron cooler were measured. Beam noise spectra are being investigated with regard to collective effects caused by the Coulomb interaction in the cold ion beams. Resonance fluorescence from stored single-charged ions was observed using tunable narrow-band lasers. First indications of laser cooling in a storage ring were seen.

  7. Presented Papers of the European Division Mathematics & Science Conference (1st, Heidelberg, West Germany, February 28-March 2, 1986).

    ERIC Educational Resources Information Center

    Maryland Univ., College Park. Univ. Coll.

    This document contains the papers presented at a conference designed to provide a forum to discuss the European Division mathematics and science program and to allow an opportunity for professional development. Papers on approaches to teaching specific topics in the Maryland mathematics and science curriculum, as well as on other aspects of…

  8. Penetration of Salmonella enteritidis and S. heidelberg strains into egg yolks during 36 hour ambient temperature storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although Salmonella deposition inside yolks is uncommon in naturally contaminated eggs, migration through the vitelline membrane into the nutrient-rich yolk contents could enable rapid bacterial multiplication. Egg refrigeration restricts both penetration and growth, but a recently proposed national...

  9. [Validation of the Child Speech Test using the Heidelberg Speech Development Test with six-year-old preschool children].

    PubMed

    Kasielke, E; Frank, K; Scheidereiter, U

    1992-01-01

    We present and discuss results from researches to validate a new test for diagnosing speech-competences of preschool children KISTE. 41 children (6;0-6;11) were tested both with KISTE and HSET. Correlations, factor- and clusteranalysis showed that the structure of both tests is different and that KISTE has a good differential validity for both aspects of speech: communicative and structural. PMID:1359718

  10. In Vitro Penetration of Egg Yolks by Salmonella Enteritidis and Salmonella Heidelberg Strains During 36-hour Ambient Temperature Storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although Salmonella deposition inside egg yolks is uncommon, migration through the vitelline membrane into the nutrient-rich yolk contents could enable rapid bacterial multiplication. Egg refrigeration restricts both penetration and growth, but a recently proposed national S. enteritidis control pro...

  11. Colonization of day-of-hatch broiler chicks with antimicrobial resistant strains of salmonella Heidelberg and Kentucky

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella is a major foodborne pathogen linked to poultry and poultry products. However, limited research regarding the in vivo interactions of non-host adapted Salmonella serotypes in broiler chicks is available. In order to evaluate the effect of two serotypes on colonization, 600 day-of-hatch ...

  12. [The Heidelberg instrument for the assessment of quality of life in dementia (H. I. L. DE.)--dimensions of quality of life and methods of organization].

    PubMed

    Becker, S; Kruse, A; Schröder, J; Seidl, U

    2005-04-01

    The contribution is intended to describe the theoretical background and measurement approach of H.I.L.DE., a research project aimed to develop and validate a comprehensive assessment of quality of life in nursing home residents suffering from dementia. Proceeding from the assumption that emotions are felt even in advanced stages of dementia and can be interpreted on the basis of peoples' mimic expressions, three samples of participants were recruited from 11 nursing homes of varying maintenance: 121 nursing home residents suffering from dementia, 97 professional caregivers and 101 relatives participated in the first wave of this study. Operational definition of quality of life in H.I.L.DE. proceeds from the differentiation of eight dimensions of quality of life: physical environment, social environment, quality of care, behavioral competence, medical and functional status, cognitive status, psychopathology and behavior disturbances, and subjective experiences of physical and social environment and emotional well-being. Measures of the eight dimensions involve data from medical examination, interviews with residents, professional caregivers and relatives, ecopsychological assessment of physical environment and analysis of care documents. First results from the H.I.L.DE.-study are used as an illustration of the potentials of such a comprehensive approach to the measurement of quality of life. PMID:15868349

  13. Characterization of extended-spectrum cephalosporin-resistant Salmonella enterica serovar Heidelberg isolated from food animals, retail meat, and humans in the United States 2009

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella enterica is one of the most common causes of foodborne illness in the United States. Although salmonellosis is usually self-limiting, severe infections typically require antimicrobial treatment and ceftriaxone, an extended-spectrum cephalosporin, is commonly used in both adults and child...

  14. Microscopic calculations of signals of double beta decay in a 76Ge detector and first application to the Heidelberg Moscow experiment

    NASA Astrophysics Data System (ADS)

    Klapdor-Kleingrothaus, H. V.; Krivosheina, I. V.; Mironov, V.; Titkova, I. V.

    2006-05-01

    The identification of signals of neutrinoless double beta decay is a question of extreme interest. Starting from the Monte Carlo calculated time history and spatial energy distribution of neutrinoless double beta events, for the first time the expected pulse shapes to be observed in a big 76Ge detector have been calculated 'microscopically', by using the Poisson Superfish code for determination of the field distribution in the detector. It is shown, that for the majority of 0 νββ events it is not possible to differentiate between the contributions of different particle physics parameters entering into the 0 νββ decay process-in the mass mechanism the effective neutrino mass and the right-handed weak current parameters < λ >, < η >. It is shown, that on the other hand it is possible in a 76Ge double beta decay experiment to reject a background of larger sizes (high multiplicity) gamma events by selecting low size (low multiplicity) events. First application of the theoretical ββ pulses to events from the line observed at Qββ [H.V. Klapdor-Kleingrothaus, I.V. Krivosheina, A. Dietz, et al., Phys. Lett. B 586 (2004) 198; H.V. Klapdor-Kleingrothaus, A. Dietz, I.V. Krivosheina, et al., Nucl. Instrum. Methods A 522 (2004) 371] shows very good agreement. It is shown further, and confirmed by measurements with a collimated source, that a rather good radial position determination of ββ events in the detector is possible. By the same type of calculation it is shown that use of the pulse shapes of the 1592 keV double escape line of the 2614 keV γ-transition from 228Th for calibrating a neuronal net for search of events of neutrinoless double beta decay can be helpful.

  15. The prevalence of Salmonella enterica serovars Heidelberg and Kentucky in the scalder water of a commercial poultry processing plant in the southeastern United States.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to assess the presence of Salmonella enterica present in the water of scalder and chiller tanks from a commercial chicken processing plant in the southeaster United States. Three liters of scald and chill water were aseptically sampled three times daily for three consec...

  16. TRIGA Mark II nuclear reactor facility. Final report, 1 July 1980--30 June 1995

    SciTech Connect

    Ryan, B.C.

    1997-05-01

    This report is a final culmination of activities funded through the Department of Energy`s (DOE) University Reactor Sharing Program, Grant DE-FG02-80ER10273, during the period 1 July 1980 through 30 June 1995. Progress reports have been periodically issued to the DOE, namely the Reactor Facility Annual Reports C00-2082/2219-7 through C00-2082/10723-21, which are contained as an appendix to this report. Due to the extent of time covered by this grant, summary tables are presented. Table 1 lists the fiscal year financial obligations of the grant. As listed in the original grant proposals, the DOE grant financed 70% of project costs, namely the total amount spent of these projects minus materials costs and technical support. Thus the bulk of funds was spent directly on reactor operations. With the exception of a few years, spending was in excess of the grant amount. As shown in Tables 2 and 3, the Reactor Sharing grant funded a immense number of research projects in nuclear engineering, geology, animal science, chemistry, anthropology, veterinary medicine, and many other fields. A list of these users is provided. Out of the average 3000 visitors per year, some groups participated in classes involving the reactor such as Boy Scout Merit Badge classes, teacher`s workshops, and summer internships. A large number of these projects met the requirements for the Reactor Sharing grant, but were funded by the University instead.

  17. 77 FR 42771 - License Renewal for the Dow Chemical TRIGA Research Reactor

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ... releases of radioactive effluents. As discussed in the NRC staff's safety evaluation, the systems and... that releases of radioactive material and personnel exposures were all well within applicable... Reactor Operations Gaseous radioactive effluents are discharged by the facility exhaust system via...

  18. Neutron dosimetry and damage calculations for the TRIGA MARK-II reactor in Vienna

    NASA Astrophysics Data System (ADS)

    Weber, H. W.; Böck, H.; Unfried, E.; Greenwood, L. R.

    1986-02-01

    In order to improve the source characterization of the reactor, especially for recent irradiation experiments in the central irradiation thimble, neutron activation experiments were made on 16 nuclides and the neutron flux spectrum was adjusted using the computer code STAY'SL. The results for the total, thermal and fast neutron flux density at a reactor power of 250 kW are as follows: 2.1 × 10 17, 6.1 × 10 16 ( E < 0.55 eV), 7.6 × 10 16 ( E > 0.1 MeV) and 4.0 × 10 16 ( E > 1 MeV) m -2 s -1. respectively. Calculated damage energy cross sections and gas production rates are presented for selected elements.

  19. Neutron activation analyses and half-life measurements at the usgs triga reactor

    NASA Astrophysics Data System (ADS)

    Larson, Robert E.

    Neutron activation of materials followed by gamma spectroscopy using high-purity germanium detectors is an effective method for making measurements of nuclear beta decay half-lives and for detecting trace amounts of elements present in materials. This research explores applications of neutron activation analysis (NAA) in two parts. Part 1. High Precision Methods for Measuring Decay Half-Lives, Chapters 1 through 8 Part one develops research methods and data analysis techniques for making high precision measurements of nuclear beta decay half-lives. The change in the electron capture half-life of 51Cr in pure chromium versus chromium mixed in a gold lattice structure is explored, and the 97Ru electron capture decay half-life are compared for ruthenium in a pure crystal versus ruthenium in a rutile oxide state, RuO2. In addition, the beta-minus decay half-life of 71mZn is measured and compared with new high precision findings. Density Functional Theory is used to explain the measured magnitude of changes in electron capture half-life from changes in the surrounding lattice electron configuration. Part 2. Debris Collection Nuclear Diagnostic at the National Ignition Facility, Chapters 9 through 11 Part two explores the design and development of a solid debris collector for use as a diagnostic tool at the National Ignition Facility (NIF). NAA measurements are performed on NIF post-shot debris collected on witness plates in the NIF chamber. In this application NAA is used to detect and quantify the amount of trace amounts of gold from the hohlraum and germanium from the pellet present in the debris collected after a NIF shot. The design of a solid debris collector based on material x-ray ablation properties is given, and calculations are done to predict performance and results for the collection and measurements of trace amounts of gold and germanium from dissociated hohlraum debris.

  20. Dosimetric feasibility study for an extracorporeal BNCT application on liver metastases at the TRIGA Mainz.

    PubMed

    Blaickner, M; Kratz, J V; Minouchehr, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L; Wortmann, B; Hampel, G

    2012-01-01

    This study investigates the dosimetric feasibility of Boron Neutron Capture Therapy (BNCT) of explanted livers in the thermal column of the research reactor in Mainz. The Monte Carlo code MCNP5 is used to calculate the biologically weighted dose for different ratios of the (10)B-concentration in tumour to normal liver tissue. The simulation results show that dosimetric goals are only partially met. To guarantee effective BNCT treatment the organ has to be better shielded from all gamma radiation. PMID:21872481

  1. Corrosion damage to the aluminum tank liner of the U.S. Geological Survey TRIGA Reactor

    SciTech Connect

    Perryman, R.E.; Millard, H.T. Jr.; Rusling, D.H.; Heifer, P.G.; Smith, W.L.

    1988-07-01

    During a routine maintenance small holes at the side of the tank of the reactor, penetrating the tank liner were discovered. Apparently the corrosion was acting from the back side of the tank forming the holes. The NRC was promptly notified and routine operations were suspended. Further investigation lead to the discovery of 74 holes, most of which were less than 1/8 inch in diameter with a few as large as 1/4 inch diameter. The results of an examination of the plate cut from the side of the tank correlated the absence of tar coating with the presence of numerous corrosion pits and craters. Along the welds in the corroded areas, parallel corrosion troughs existed on either side of the weld. Most of the pits and craters were too small to be detected by ultrasonic survey. In order to remedy the physical problem and be able to resume the reactor operation, a short-term strategy was adopted which involved covering the 74 holes with aluminum patches coated with epoxy. Reactor operations were resumed and over the next month four new holes were found and four patches applied. An inspection conducted after four months of operation found 28 new holes and the rate of leakage of water from the tank had increased to about 0.7 l/h. Because the rate of formation of holes seemed to be accelerating and the time required for maintenance was becoming unacceptable, it was decided to cease operation of the reactor until long-term repairs could be made. A new aluminum tank liner will be installed within the existing tank. A 2-inch wide annular void will then exist between the new and old liners. A pump will be installed inside the new liner to prevent the ground water from contacting it. The top of the void will be shielded to reduce the exposure to neutrons and gamma rays scattered from areas near the reactor. The reactor will be reinstalled at the bottom of the new liner on a plate which can be levelled from a distance of 10 feet.

  2. Corrosion in the aluminum containment tank at the Nuclear Center of Mexico TRIGA Mark III reactor

    SciTech Connect

    Mota, Juan Ramon

    1986-07-01

    The reactor developed a leak inside the exposure room discovered when it was opened for a routine inspection. This leak started to diminish immediately after it was found and disappeared completely in 2.5 months. The hydrostatic tests of the exposure room cooling water pipes and of the primary cooling system suction pipe proved that piping do not have leaks. A portion of the total volume of water was drained from the pool to conduct an inspection on the aluminum liner. Penetrant dye tests were initiated over welded Joints and walls. Welded Joints were all found to be in good condition but a total of 35 indications were reported on walls and concentrated on two main areas. A vacuum system was used to test for leakage. Seven indications were found to be perforations that crossed through the wall, fifteen indications did not cross through the wall but required repair and the rest were superficial irregularities. For the inspection of surfaces that remained covered by water, two methods were used. One was a television camera that was adapted to be used under water and hooked to a monitor and a videorecorder for close up inspection of the walls. The other consisted of submarine still color photography performed by divers. The evaluation of these inspections concluded that out of the 10 areas previously identified, only one presented the kind of problem that required repair. The last inspection performed was that using ultrasound techniques. Irregularities found did not require complete replacement of the aluminum liner. The repair procedures included the welding of aluminum plates over damaged areas and the injection of an effective insulating material (resin) to stop the corrosion mechanism.

  3. Development and methodology of level 1 probability safety assessment at PUSPATI TRIGA Reactor

    SciTech Connect

    Maskin, Mazleha; Tom, Phongsakorn Prak; Lanyau, Tonny Anak; Saad, Mohamad Fauzi; Ismail, Ahmad Razali; Abu, Mohamad Puad Haji; Brayon, Fedrick Charlie Matthew; Mohamed, Faizal

    2014-02-12

    As a consequence of the accident at the Fukushima Dai-ichi Nuclear Power Plant in Japan, the safety aspects of the one and only research reactor (31 years old) in Malaysia need be reviewed. Based on this decision, Malaysian Nuclear Agency in collaboration with Atomic Energy Licensing Board and Universiti Kebangsaan Malaysia develop a Level-1 Probability Safety Assessment on this research reactor. This work is aimed to evaluate the potential risks of incidents in RTP and at the same time to identify internal and external hazard that may cause any extreme initiating events. This report documents the methodology in developing a Level 1 PSA performed for the RTP as a complementary approach to deterministic safety analysis both in neutronics and thermal hydraulics. This Level-1 PSA work has been performed according to the procedures suggested in relevant IAEA publications and at the same time numbers of procedures has been developed as part of an Integrated Management System programme implemented in Nuclear Malaysia.

  4. Development and methodology of level 1 probability safety assessment at PUSPATI TRIGA Reactor

    NASA Astrophysics Data System (ADS)

    Maskin, Mazleha; Tom, Phongsakorn Prak; Lanyau, Tonny Anak; Brayon, Fedrick Charlie Matthew; Mohamed, Faizal; Saad, Mohamad Fauzi; Ismail, Ahmad Razali; Abu, Mohamad Puad Haji

    2014-02-01

    As a consequence of the accident at the Fukushima Dai-ichi Nuclear Power Plant in Japan, the safety aspects of the one and only research reactor (31 years old) in Malaysia need be reviewed. Based on this decision, Malaysian Nuclear Agency in collaboration with Atomic Energy Licensing Board and Universiti Kebangsaan Malaysia develop a Level-1 Probability Safety Assessment on this research reactor. This work is aimed to evaluate the potential risks of incidents in RTP and at the same time to identify internal and external hazard that may cause any extreme initiating events. This report documents the methodology in developing a Level 1 PSA performed for the RTP as a complementary approach to deterministic safety analysis both in neutronics and thermal hydraulics. This Level-1 PSA work has been performed according to the procedures suggested in relevant IAEA publications and at the same time numbers of procedures has been developed as part of an Integrated Management System programme implemented in Nuclear Malaysia.

  5. Reactor Physics Scoping and Characterization Study on Implementation of TRIGA Fuel in the Advanced Test Reactor

    SciTech Connect

    Jennifer Lyons; Wade R. Marcum; Mark D. DeHart; Sean R. Morrell

    2014-01-01

    The Advanced Test Reactor (ATR), under the Reduced Enrichment for Research and Test Reactors (RERTR) Program and the Global Threat Reduction Initiative (GTRI), is conducting feasibility studies for the conversion of its fuel from a highly enriched uranium (HEU) composition to a low enriched uranium (LEU) composition. These studies have considered a wide variety of LEU plate-type fuels to replace the current HEU fuel. Continuing to investigate potential alternatives to the present HEU fuel form, this study presents a preliminary analysis of TRIGA® fuel within the current ATR fuel envelopes and compares it to the functional requirements delineated by the Naval Reactors Program, which includes: greater than 4.8E+14 fissions/s/g of 235U, a fast to thermal neutron flux ratio that is less than 5% deviation of its current value, a constant cycle power within the corner lobes, and an operational cycle length of 56 days at 120 MW. Other parameters outside those put forth by the Naval Reactors Program which are investigated herein include axial and radial power profiles, effective delayed neutron fraction, and mean neutron generation time.

  6. Methods of reducing liquid effluent from the OSU TRIGA MKII Reactor

    SciTech Connect

    Higginbotham, J.F.; Dodd, B.; Pratt, D.S.; Smith, S.; Anderson, T.V.

    1992-07-01

    In 1991, the OSU Radiation Center implemented a program to minimize the liquid effluent generated by the reactor facility. The goal of program is to become a 'zero' release facility with regards to routine liquid discharges. Only two liquid waste streams exist for the OSU reactor facility: discharges resulting from changing resin in the deminerializer and decontamination of equipment, primarily sample loading tubes. This paper describes a system which allows remote resin exchange to performed with the collection of all flush water. This water is then recycled for use as makeup for the primary water system. The service life of the resin is maximized by using a steam distillation unit as the source of makeup water to the deminerializer system instead of water coming directly from the City of Corvallis water supply. The second source of liquid waste water comes from the decontamination of the plastic loading tubes used to encapsulate samples. This process originally involved placing the tubes in a dishwasher and sending the discharge to a hold up tank. If the radionuclide concentrations in the tank were below the maximum permissible concentrations of 10CFR20 then it was released to the sanitary sewerage. This process was replaced in 1991 with a system which involved manual washing and rinsing of the tubes with the liquids being absorbed for disposal as solid waste. This paper will also describe the system which is being built to replace this process. It will use the dishwasher unit again but the liquid discharge will collected for absorption and disposal as solid waste. (author)

  7. Feasibility study of the University of Utah TRIGA reactor power upgrade in respect to control rod system

    NASA Astrophysics Data System (ADS)

    Cutic, Avdo

    The objectives of this thesis are twofold: to determine the highest achievable power levels of the current University of Utah TRIG Reactor (UUTR) core configuration with the existing three control rods, and to design the core for higher reactor power by optimizing the control rod worth. For the current core configuration, the maximum reactor power, eigenvalue keff, shutdown margin, and excess reactivity have been measured and calculated. These calculated estimates resulted from thermal power calibrations, and the control rod worth measurements at various power levels. The results were then used as a benchmark to verify the MCNP5 core simulations for the current core and then to design a core for higher reactor power. This study showed that the maximum achievable power with the current core configuration and control rod system is 150kW, which is 50kW higher than the licensed power of the UUTR. The maximum achievable UUTR core power with the existing fuel is determined by optimizing the core configuration and control rod worth, showing that a power upgrade of 500 kW is achievable. However, it requires a new control rod system consisting of a total of four control rods. The cost of such an upgrade is $115,000.

  8. MCNP5 and GEANT4 comparisons for preliminary Fast Neutron Pencil Beam design at the University of Utah TRIGA system

    NASA Astrophysics Data System (ADS)

    Adjei, Christian Amevi

    The main objective of this thesis is twofold. The starting objective was to develop a model for meaningful benchmarking of different versions of GEANT4 against an experimental set-up and MCNP5 pertaining to photon transport and interactions. The following objective was to develop a preliminary design of a Fast Neutron Pencil Beam (FNPB) Facility to be applicable for the University of Utah research reactor (UUTR) using MCNP5 and GEANT4. The three various GEANT4 code versions, GEANT4.9.4, GEANT4.9.3, and GEANT4.9.2, were compared to MCNP5 and the experimental measurements of gamma attenuation in air. The average gamma dose rate was measured in the laboratory experiment at various distances from a shielded cesium source using a Ludlum model 19 portable NaI detector. As it was expected, the gamma dose rate decreased with distance. All three GEANT4 code versions agreed well with both the experimental data and the MCNP5 simulation. Additionally, a simple GEANT4 and MCNP5 model was developed to compare the code agreements for neutron interactions in various materials. Preliminary FNPB design was developed using MCNP5; a semi-accurate model was developed using GEANT4 (because GEANT4 does not support the reactor physics modeling, the reactor was represented as a surface neutron source, thus a semi-accurate model). Based on the MCNP5 model, the fast neutron flux in a sample holder of the FNPB is obtained to be 6.52×107 n/cm2s, which is one order of magnitude lower than gigantic fast neutron pencil beam facilities existing elsewhere. The MCNP5 model-based neutron spectrum indicates that the maximum expected fast neutron flux is at a neutron energy of ~1 MeV. In addition, the MCNP5 model provided information on gamma flux to be expected in this preliminary FNPB design; specifically, in the sample holder, the gamma flux is to be expected to be around 108 γ/cm 2s, delivering a gamma dose of 4.54×103 rem/hr. This value is one to two orders of magnitudes below the gamma exposure as exists in the currently used fast neutron irradiation facility at the UUTR. The GEANT4.9.4 semi-accurate model of the FNPB design provided higher values for neutron and gamma fluxes, indicating the importance of transfering the data from MCNP5 rather than using the GEANT4 default neutron spectra.

  9. Chemical and material studies to understand the source of corrosion in the Geological Survey TRIGA Reactor (GSTR) tank liner

    SciTech Connect

    Rusling, D.H.; Millard, H.T. Jr.; Heifer, P.G.; Perryman, R.E.; Smith, W.L.

    1988-07-01

    Corrosion damage to the aluminum tank liner of the GSTR reactor was discovered and samples of various materials were collected for chemical and mineralogical analyses. The following scenario for the corrosion was suggested: 1. Cyclical temperature changes caused the tank liner to change size repeatedly. It extruded tar as it expanded and created voids as it contracted. 2. Hydrostatic pressure forced ground water through openings in the concrete into voids near the bottom of the tank, and overflow introduced tank water at the top of the tank. 3. The expansion-contraction cycle moved the water around the complex, interconnecting systems of voids and, in some locations, caused the tar-to-aluminum bond to fail. 4. Chemical interactions of the water with the tar and concrete supplied the elements capable of corroding the aluminum (e.g., Zn, Cu). 5. The corrosive solution has reacted with the aluminum over the lifetime of the reactor to produce the present corrosion damage. 6. As corrosion pits became holes, reactor tank water entered the voids.

  10. McClellan Nuclear Radiation Center (MNRC) TRIGA reactor: The national organization of test research and training reactors

    SciTech Connect

    Kiger, Kevin M.

    1994-07-01

    This year's TRTR conference is being hosted by the McClellan Nuclear Radiation Center. The conference will be held at the Red Lion Hotel in Sacramento, CA. The conference dates are scheduled for October 11-14, 1994. Deadlines for sponsorship commitment and papers have not been set, but are forthcoming. The newly remodeled Red Lion Hotel provides up-to-date conference facilities and one of the most desirable locations for dining, shopping and entertainment in the Sacramento area. While attendees are busy with the conference activities, a spouses program will be available. Although the agenda has not been set, the Sacramento area offers outings to San Francisco, Pier 39, Ghirardelli Square (famous for their chocolate), and a chance to discover 'El Dorado' in the gold country. Not to forget our own bit of history with visits to 'Old Sacramento and Old Folsom', where antiquities abound, to the world renown train museum and incredible eating establishments. (author)

  11. Thermal hydraulic calculations to support increase in operating power in McClellen Nuclear Radiation Center(MNRC) TRIGA reactor.

    SciTech Connect

    Jensen, R. T.

    1998-05-05

    The RELAP5/Mod3.1 computer program has been used to successfully perform thermal-hydraulic analyses to support the Safety Analysis for increasing the MNRC reactor from 1.0 MW to 2.0 MW. The calculation results show the reactor to have operating margin for both the fuel temperature and critical heat flux limits. The calculated maximum fuel temperature of 705 C is well below the 750 C operating limit. The critical heat flux ratio was calculated to be 2.51.

  12. 77 FR 7613 - Dow Chemical Company; Dow Chemical TRIGA Research Reactor; Facility Operating License No. R-108

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-13

    ... provides text and image files of the NRC's public documents. If you do not have access to ADAMS or if there... in the hearing. For each contention, the petitioner must provide a specific statement of the issue of... contention. Additionally, the petitioner must demonstrate that the issue raised by each contention is...

  13. 77 FR 68155 - The Armed Forces Radiobiology Research Institute TRIGA Reactor: Facility Operating License No. R-84

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-15

    ... NRC's E-Filing rule (72 FR 49139; August 28, 2007). The E-Filing process requires participants to... filing requirements of the NRC's E-Filing Rule (72 FR 49139; August 28, 2007) apply to appeals of NRC... at a maximum steady-state thermal power of 1.1 megawatts (MW). The renewed license would...

  14. Toward a population genetic analysis of Salmonella: genetic diversity and relationships among strains of serotypes S. choleraesuis, S. derby, S. dublin, S. enteritidis, S. heidelberg, S. infantis, S. newport, and S. typhimurium.

    PubMed

    Beltran, P; Musser, J M; Helmuth, R; Farmer, J J; Frerichs, W M; Wachsmuth, I K; Ferris, K; McWhorter, A C; Wells, J G; Cravioto, A

    1988-10-01

    Variation in the chromosomal genomes of 1527 isolates of eight common serotypes (O and H antigen profiles) of Salmonella was assessed by analysis of electrophoretically demonstrable allelic polymorphism at 23 metabolic enzyme loci. Seventy-one distinctive electrophoretic types, representing multilocus genotypes, were identified. A basically clonal population structure was indicated by the presence of strong linkage disequilibrium among enzyme loci, the association of each serotype with a relatively small number of multilocus enzyme genotypes, and the global distribution of certain genotypes. For each of six of the serotypes, 83-96% of isolates were members of a single clone. The occurrence of each of four serotypes (S. derby, S. enteritidis, S. infantis, and S. newport) in isolates of clones belonging to several evolutionary lineages, some of which are distantly related, suggests that the horizontal transfer and recombination of chromosomal genes mediating expression of cell-surface antigens has been a significant process in the evolution of the salmonellae. Two divergent clone clusters of S. derby differ in the relative frequency with which they cause disease in birds versus mammals, and two major lineages of S. newport differ in the frequency with which their clones are associated with disease in humans versus animals. PMID:3051004

  15. Morphometric Optic Nerve Head Analysis in Glaucoma Patients: A Comparison between the Simultaneous Nonmydriatic Stereoscopic Fundus Camera (Kowa Nonmyd WX3D) and the Heidelberg Scanning Laser Ophthalmoscope (HRT III).

    PubMed

    Mariacher, Siegfried; Hipp, Stephanie; Wirthky, Robert; Blumenstock, Gunnar; Bartz-Schmidt, Karl-Ulrich; Ziemssen, Focke; Schiefer, Ulrich; Voykov, Bogomil; Januschowski, Kai

    2016-01-01

    Purpose. To investigate the agreement between morphometric optic nerve head parameters assessed with the confocal laser ophthalmoscope HRT III and the stereoscopic fundus camera Kowa nonmyd WX3D retrospectively. Methods. Morphometric optic nerve head parameters of 40 eyes of 40 patients with primary open angle glaucoma were analyzed regarding their vertical cup-to-disc-ratio (CDR). Vertical CDR, disc area, cup volume, rim volume, and maximum cup depth were assessed with both devices by one examiner. Mean bias and limits of agreement (95% CI) were obtained using scatter plots and Bland-Altman analysis. Results. Overall vertical CDR comparison between HRT III and Kowa nonmyd WX3D measurements showed a mean difference (limits of agreement) of -0.06 (-0.36 to 0.24). For the CDR < 0.5 group (n = 24) mean difference in vertical CDR was -0.14 (-0.34 to 0.06) and for the CDR ≥ 0.5 group (n = 16) 0.06 (-0.21 to 0.34). Conclusion. This study showed a good agreement between Kowa nonmyd WX3D and HRT III with regard to widely used optic nerve head parameters in patients with glaucomatous optic neuropathy. However, data from Kowa nonmyd WX3D exhibited the tendency to measure larger CDR values than HRT III in the group with CDR < 0.5 group and lower CDR values in the group with CDR ≥ 0.5. PMID:27313870

  16. Sequential FDG-PET and induction chemotherapy in locally advanced adenocarcinoma of the Oesophago-gastric junction (AEG): The Heidelberg Imaging program in Cancer of the oesophago-gastric junction during Neoadjuvant treatment: HICON trial

    PubMed Central

    2011-01-01

    Background 18-Fluorodeoxyglucose-PET (18F-FDG-PET) can be used for early response assessment in patients with locally advanced adenocarcinomas of the oesophagogastric junction (AEG) undergoing neoadjuvant chemotherapy. It has been recently shown in the MUNICON trials that response-guided treatment algorithms based on early changes of the FDG tumor uptake detected by PET are feasible and that they can be implemented into clinical practice. Only 40%-50% of the patients respond metabolically to therapy. As metabolic non-response is known to be associated with a dismal prognosis, metabolic non-responders are increasingly treated with alternative neoadjuvant chemotherapies or chemoradiation in order to improve their clinical outcome. We plan to investigate whether PET can be used as response assessment during radiochemotherapy given as salvage treatment in early metabolic non-responders to standard chemotherapy. Methods/Design The HICON trial is a prospective, non-randomized, explorative imaging study evaluating the value of PET as a predictor of histopathological response in metabolic non-responders. Patients with resectable AEG type I and II according to Siewerts classification, staged cT3/4 and/or cN+ and cM0 by endoscopic ultrasound, spiral CT or MRI and FDG-PET are eligible. Tumors must be potentially R0 resectable and must have a sufficient FDG-baseline uptake. Only metabolic non-responders, showing a < 35% decrease of SUV two weeks after the start of neoadjuvant chemotherapy are eligible for the study and are taken to intensified taxane-based RCT (chemoradiotherapy (45 Gy) before surgery. 18FDG-PET scans will be performed before ( = Baseline) and after 14 days of standard neoadjuvant therapy as well as after the first cycle of salvage docetaxel/cisplatin chemotherapy (PET 1) and at the end of radiochemotherapy (PET2). Tracer uptake will be assessed semiquantitatively using standardized uptake values (SUV). The percentage difference ΔSUV = 100 (SUVBaseline - SUV PET1)/SUVBaseline will be calculated and assessed as an early predictor of histopathological response. In a secondary analysis, the association between the difference SUVPET1 - SUVPET2 and histopathological response will be evaluated. Discussion The aim of this study is to investigate the potential of sequential 18FDG-PET in predicting histopathological response in AEG tumors to salvage neoadjuvant radiochemotherapy in patients who do not show metabolic response to standard neoadjuvant chemotherapy. Trial Registration Clinical trial identifier NCT01271322 PMID:21702914

  17. Morphometric Optic Nerve Head Analysis in Glaucoma Patients: A Comparison between the Simultaneous Nonmydriatic Stereoscopic Fundus Camera (Kowa Nonmyd WX3D) and the Heidelberg Scanning Laser Ophthalmoscope (HRT III)

    PubMed Central

    Mariacher, Siegfried; Wirthky, Robert; Blumenstock, Gunnar; Bartz-Schmidt, Karl-Ulrich; Ziemssen, Focke; Schiefer, Ulrich; Voykov, Bogomil; Januschowski, Kai

    2016-01-01

    Purpose. To investigate the agreement between morphometric optic nerve head parameters assessed with the confocal laser ophthalmoscope HRT III and the stereoscopic fundus camera Kowa nonmyd WX3D retrospectively. Methods. Morphometric optic nerve head parameters of 40 eyes of 40 patients with primary open angle glaucoma were analyzed regarding their vertical cup-to-disc-ratio (CDR). Vertical CDR, disc area, cup volume, rim volume, and maximum cup depth were assessed with both devices by one examiner. Mean bias and limits of agreement (95% CI) were obtained using scatter plots and Bland-Altman analysis. Results. Overall vertical CDR comparison between HRT III and Kowa nonmyd WX3D measurements showed a mean difference (limits of agreement) of −0.06 (−0.36 to 0.24). For the CDR < 0.5 group (n = 24) mean difference in vertical CDR was −0.14 (−0.34 to 0.06) and for the CDR ≥ 0.5 group (n = 16) 0.06 (−0.21 to 0.34). Conclusion. This study showed a good agreement between Kowa nonmyd WX3D and HRT III with regard to widely used optic nerve head parameters in patients with glaucomatous optic neuropathy. However, data from Kowa nonmyd WX3D exhibited the tendency to measure larger CDR values than HRT III in the group with CDR < 0.5 group and lower CDR values in the group with CDR ≥ 0.5. PMID:27313870

  18. Representation and Exchange of Knowledge as a Basis of Information Processes. Proceedings of the International Research Forum in Information Science (5th, Heidelberg, West Germany, September 5-7, 1983).

    ERIC Educational Resources Information Center

    Dietschmann, Hans, Ed.

    This 22-paper collection addresses a variety of issues related to representation and transfer of knowledge. Individual papers include an explanation of the usefulness of general scientific models versus case-specific approaches and a discussion of different empirical approaches to the general problem of knowledge representation for information…

  19. Boron determination in liver tissue by combining quantitative neutron capture radiography (QNCR) and histological analysis for BNCT treatment planning at the TRIGA Mainz.

    PubMed

    Schütz, C; Brochhausen, C; Altieri, S; Bartholomew, K; Bortolussi, S; Enzmann, F; Gabel, D; Hampel, G; Kirkpatrick, C J; Kratz, J V; Minouchehr, S; Schmidberger, H; Otto, G

    2011-09-01

    The typical primary malignancies of the liver are hepatocellular carcinoma and cholangiocarcinoma, whereas colorectal liver metastases are the most frequently occurring secondary tumors. In many cases, only palliative treatment is possible. Boron neutron capture therapy (BNCT) represents a technique that potentially destroys tumor tissue selectively by use of externally induced, locally confined secondary particle irradiation. In 2001 and 2003, BNCT was applied to two patients with colorectal liver metastases in Pavia, Italy. To scrutinize the rationale of BNCT, a clinical pilot study on patients with colorectal liver metastases was carried out at the University of Mainz. The distribution of the (10)B carrier (p-borono-phenylalanine) in the liver and its uptake in cancerous and tumor-free tissue were determined, focusing on a potential correlation between the uptake of p-borono-phenylalanine and the biological characteristics of cancerous tissue. Samples were analyzed using quantitative neutron capture radiography of cryosections combined with histological analysis. Methodological aspects of the combination of these techniques and results from four patients enrolled in the study are presented that indicate that the uptake of p-borono-phenylalanine strongly depends on the metabolic activity of cells. PMID:21692653

  20. Gamma residual radioactivity measurements on rats and mice irradiated in the thermal column of a TRIGA Mark II reactor for BNCT.

    PubMed

    Protti, Nicoletta; Manera, Sergio; Prata, Michele; Alloni, Daniele; Ballarini, Francesca; di Tigliole, Andrea Borio; Bortolussi, Silva; Bruschi, Piero; Cagnazzo, Marcella; Garioni, Maria; Postuma, Ian; Reversi, Luca; Salvini, Andrea; Altieri, Saverio

    2014-12-01

    The current Boron Neutron Capture Therapy (BNCT) experiments performed at the University of Pavia, Italy, are focusing on the in vivo irradiations of small animals (rats and mice) in order to evaluate the effectiveness of BNCT in the treatment of diffused lung tumors. After the irradiation, the animals are manipulated, which requires an evaluation of the residual radioactivity induced by neutron activation and the relative radiological risk assessment to guarantee the radiation protection of the workers. The induced activity in the irradiated animals was measured by high-resolution open geometry gamma spectroscopy and compared with values obtained by Monte Carlo simulation. After an irradiation time of 15 min in a position where the in-air thermal flux is about 1.2 × 10(10) cm(-2) s(-1), the specific activity induced in the body of the animal is mainly due to 24Na, 38Cl, 42K, 56Mn, 27Mg and 49Ca; it is approximately 540 Bq g(-1) in the rat and around 2,050 Bq g(-1) in the mouse. During the irradiation, the animal body (except the lung region) is housed in a 95% enriched 6Li shield; the primary radioisotopes produced inside the shield by the neutron irradiation are 3H by the 6Li capture reaction and 18F by the reaction sequence 6Li(n,α)3H → 16O(t,n)18F. The specific activities of these products are 3.3 kBq g(-1) and 880 Bq g(-1), respectively. PMID:25353239

  1. Self-triggering readout system for the neutron lifetime experiment PENeLOPE

    NASA Astrophysics Data System (ADS)

    Gaisbauer, D.; Konorov, I.; Steffen, D.; Paul, S.

    2016-07-01

    The aim of PENeLOPE (Precision Experiment on Neutron Lifetime Operating with Proton Extraction) at the Forschungsreaktor München II is a high-precision measurement of the neutron lifetime and thereby an improvement of the parameter's precision by one order of magnitude. In order to achieve a higher accuracy, modern experiments naturally require state-of-the-art readout electronics, as well as high-performance data acquisition systems. This paper presents the self-triggering readout system designed for PENeLOPE which features a continuous pedestal tracking, configurable signal detection logic, floating ground up to 30 kV, cryogenic environment and the novel Switched Enabling Protocol (SEP). The SEP is a time-division multiplexing transport level protocol developed for a star network topology.

  2. A Leadership Journey

    ERIC Educational Resources Information Center

    Knudsen, Gene

    2007-01-01

    This article features Ellen Minette, principal of Heidelberg Middle School in Heidelberg, Germany. Minette attended 13 schools before she graduated from high school. Her father, an Air Force pilot who served in the Korean War and who was a part of the Berlin Airlift, was deployed much of the time as they moved from one posting to another. Growing…

  3. 76 FR 21928 - Washington State University; Facility Operating License No. R-76; Washington State University...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... Modified TRIGA Nuclear Radiation Center Reactor (NRCR); Environmental Assessment and Finding of No... TRIGA Nuclear Radiation Center Reactor (NRCR), located in the Dodgen Research Facility on Roundtop Drive... of quarterly exposure measurements at 12 locations adjacent to the Nuclear Radiation Center and at...

  4. Hadron Cancer Therapy - relative merits of X-ray, proton and carbon beams

    NASA Astrophysics Data System (ADS)

    Jakel, Oliver

    2014-03-01

    -Heidelberg University has a long experience in radiotherapy with carbon ions, starting with a pilot project at GSI in 1997. This project was jointly run by the Dep. for Radiation Oncology of Heidelberg University, GSI and the German Cancer Research Center (DKFZ). A hospital based heavy ion center at Heidelberg University, the Heidelberg Ion Beam Therapy Center (HIT) was proposed by the same group in 1998 and started clinical operation in late 2009. Since then nearly 2000 patients were treated with beams of carbon ions and protons. Just recently the operation of the world's first and only gantry for heavy ions also started at HIT. Patient treatments are performed in three rooms. Besides that, a lot of research projects are run in the field of Medical Physics and Radiobiology using a dedicated experimental area and the possibility to use beams of protons, carbon, helium and oxygen ions being delivered with the raster scanning technique.

  5. Large Surveys & Simulations -- The Real and the Virtual Universe

    NASA Astrophysics Data System (ADS)

    von Berlepsch, Regina

    2012-06-01

    The current issue of AN is Volume 24 of the Reviews in Modern Astronomy and presents selected papers given at the International Scientific Conference of the Society on ``Surveys & Simulations -- The Real and the Virtual Universe'' held in Heidelberg, Germany, September 19-23, 2011. The ``Astronomische Gesellschaft'' was actually founded in Heidelberg in 1863 and there has been a close connection between the AG and the colleagues in Heidelberg ever since. It was the sixth time that Heidelberg hosted a meeting of the AG. In 2011 the meeting took place at the Ruprecht-Karls-University, Germany's oldest university, celebrating its 625th anniversary. The meeting was attended by more than 400 participants from around the world.

  6. 2. GENERAL VIEW SHOWING RELATION OF BRIDGE TO THE TOPOGRAPHY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GENERAL VIEW SHOWING RELATION OF BRIDGE TO THE TOPOGRAPHY OF THE APPROACH ROAD. - Speicher Bridge, Church Road over Tulpehocken Creek between Penn & North Heidelberg Townships, Bernville, Berks County, PA

  7. 1. Historic American Buildings Survey, Taken from Harold E. Dickson: ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Taken from Harold E. Dickson: A Hundred Pennsylvania Buildings (State College, PA.: Bald Eagle Press, 1954) PHOTOCOPY OF C.1906 PHOTOGRAPH. - Heidelberg Apartments & Cottages, Braddock Avenue & Waverly Street, Pittsburgh, Allegheny County, PA

  8. 7. Anthony Bley, Photographer September, 1976 L TO R: TWO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Anthony Bley, Photographer September, 1976 L TO R: TWO CHICKEN HOUSES, PIG BARN, MILKSHED, BARN - Dundore Farm, State Route 183 & Church Road vicinity, Penn Township (moved to Brownsville vicinity, Lower Heidelberg Township, Berks County), Mount Pleasant, Berks County, PA

  9. 1. Summer, 1975 L TO R: PRIVY, PIG BARN, SILO, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Summer, 1975 L TO R: PRIVY, PIG BARN, SILO, BARN - Konig-Speicher Farm, North side of Church Road, south of Tulpehocken Creek, North Heidelberg Township (moved to Willow Street, Lenhartsville, Berks County), Mount Pleasant, Berks County, PA

  10. 6. Anthony Bley, Photographer Summer, 1975 L TO R: GRANARY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Anthony Bley, Photographer Summer, 1975 L TO R: GRANARY, TWO CHICKEN HOUSES, PIG BARN - Dundore Farm, State Route 183 & Church Road vicinity, Penn Township (moved to Brownsville vicinity, Lower Heidelberg Township, Berks County), Mount Pleasant, Berks County, PA

  11. Metabolic parameters linked by Phenotype MicroArray to acid resistance profiles of poultry-associated Salmonella enterica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenotype microarrays were analyzed for 51 datasets derived from Salmonella enterica. The top 4 serovars associated with poultry products and one associated with turkey, respectively Typhimurium, Enteritidis, Heidelberg, Infantis and Senftenberg, were represented. Datasets were clustered into two ...

  12. Identification and characterization of salmonella serotypes using DNA spectral characteristics by fourier transform infrared (FT-IR) spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analysis of DNA samples of Salmonella serotypes (Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky) were performed using Fourier transform infrared spectroscopy (FT-IR) spectrometer by placing directly in contact with a diamond attenua...

  13. Efficacy of Lytic Bacteriophage Preparation in Reducing Salmonella In Vitro, on Turkey Breast Cutlets, and on Ground Turkey.

    PubMed

    Sharma, C S; Dhakal, J; Nannapaneni, R

    2015-07-01

    The efficacy of the recently approved Salmonella lytic bacteriophage preparation (SalmoFresh) in reducing Salmonella enterica serotype Heidelberg on turkey breast cutlets and ground turkey was evaluated. In a broth model assay, the phage preparation completely inhibited the growth of four S. enterica serotypes (Salmonella Enteritidis, Salmonella Heidelberg, Salmonella Kentucky, and Salmonella Typhimurium) at 37°C at a multiplicity of infection of 10,000 PFU/CFU. At 4°C in 0.1% peptone water (PW), phage treatment at a multiplicity of infection of 10,000 resulted in ca. 4.0-log CFU/ml reductions of Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium. When raw turkey breast cutlets inoculated with Salmonella Heidelberg (∼10(3) CFU/g) were treated with phage preparation (10(7) PFU/g) and stored at 4°C, the phage treatment caused reductions of 0.8, 0.6, and 1.3 log CFU/g (P ≤ 0.05) of Salmonella Heidelberg on day 0, 1, and 7, respectively, compared with the counts in the control. However, no significant reduction of Salmonella Heidelberg (P > 0.05) was observed in ground turkey when turkey meat pieces inoculated with Salmonella Heidelberg were surface treated with phage preparation (10(7) PFU/g) before grinding. These findings indicate that the bacteriophage preparation was effective in reducing Salmonella on turkey breast cutlets as a surface treatment but did not cause any reduction of Salmonella Heidelberg in ground turkey. PMID:26197288

  14. Neutron flux and power in RTP core-15

    NASA Astrophysics Data System (ADS)

    Rabir, Mohamad Hairie; Zin, Muhammad Rawi Md; Usang, Mark Dennis; Bayar, Abi Muttaqin Jalal; Hamzah, Na'im Syauqi Bin

    2016-01-01

    PUSPATI TRIGA Reactor achieved initial criticality on June 28, 1982. The reactor is designed to effectively implement the various fields of basic nuclear research, manpower training, and production of radioisotopes. This paper describes the reactor parameters calculation for the PUSPATI TRIGA REACTOR (RTP); focusing on the application of the developed reactor 3D model for criticality calculation, analysis of power and neutron flux distribution of TRIGA core. The 3D continuous energy Monte Carlo code MCNP was used to develop a versatile and accurate full model of the TRIGA reactor. The model represents in detailed all important components of the core with literally no physical approximation. The consistency and accuracy of the developed RTP MCNP model was established by comparing calculations to the available experimental results and TRIGLAV code calculation.

  15. Determination of Unknown Neutron Cross Sections for the Production of Medical Isotopes

    SciTech Connect

    Stephen E. Binney

    2004-04-09

    Calculational assessment and experimental verification of certain neutron cross sections that are related to widely needed new medical isotopes. Experiments were performed at the Oregon State University TRIGA Reactor and the High Flux Irradiation Reactor at Oak Ridge National Laboratory.

  16. Dose Rate Calucaltion for the DHL W/DOE SNF Codisposal Waste Package

    SciTech Connect

    G. Radulescu

    2000-02-12

    The purpose of this calculation is to determine the surface dose rates of the short codisposal waste package (WP) of defense high-level waste (DHLW) and TRIGA (Training, Research, Isotopes, General Atomics) spent nuclear fuel (SNF). The WP contains the TRIGA SNF, in a standardized 18-in. DOE (U.S. Department of Energy) SNF canister, and five 3-m-long Savannah River Site (SRS) DHLW pour glass canisters, which surround the DOE SNF canister.

  17. Noninvasive Ph-telemetric Measurement of Gastrointestinal Function

    NASA Technical Reports Server (NTRS)

    Tietze, Karen J.

    1991-01-01

    The purpose of this study was to gain experience with and validate the Heidelberg pH-telemetric methodology in order to determine if the pH-telemetric methodology would be a useful noninvasive measure of gastrointestinal transit time for future ground-based and in-flight drug evaluation studies. The Heidelberg pH metering system is a noninvasive, nonradioactive telemetric system that, following oral ingestion, continuously measures intraluminal pH of the stomach, duodenum, small bowel, ileocecal junction, and large bowel. Gastrointestinal motility profiles were obtained in normal volunteers using the lactulose breath-hydrogen and Heidelberg pH metering techniques. All profiles were obtained in the morning after an overnight fast. Heidelberg pH profiles were obtained in the fasting and fed states; lactulose breath-hydrogen profiles were obtained after a standard breakfast. Mouth-to-cecum transit time was measured as the interval from administration of lactulose (30 ml; 20 g) to a sustained increase in breath-hydrogen of 10 ppm or more. Gastric emptying time was measured as the interval from the administration of the Heidelberg capsule to a sustained increase in pH of three units or more.

  18. How to Build and Use Special Purpose PC Clusters in Stellar Dynamics

    NASA Astrophysics Data System (ADS)

    Spurzem, R.

    2006-08-01

    The advent of special purpose GRAPE (GRAvity PipE) chips and boards by astronomers in Tokyo has given a boost to the field of gravothermal stellar dynamics, dense stellar systems in which two-body relaxation effects cannot be neglected. Recently, GRAPE boards are used in parallel PC clusters world wide. An overview will be given from a users viewpoint of how to build and operate such a GRAPE cluster (with a focus on experiences with the Heidelberg and Rochester clusters); it is discussed what kinds of software we have suitable for such clusters and how its performance scales, with a focus on direct high-accuracy N-body codes. Typical astrophysical applications like dynamical simulations of globular clusters and galactic nuclei with massive black holes will be shown as examples what can be achieved with present hardware and software. Finally, new perspectives to use reconfigurable hardware (FPGA, MPRACE) used in addition to (in the future possibly instead of) the GRAPE, are presented, together with first benchmarks obtained from the Heidelberg GRACE cluster (GRAPE + MPRACE). This paper partly presents results obtained within the collaborations GRACE http://www.ari.uni-heidelberg.de/grace (Heidelberg), grapecluster http://www.cs.rit.edu/~grapecluster/ (Rochester), RSDN http://www.ari.uni-heidelberg.de/rsdn/ (Rhine Stell. Dyn. Network)

  19. Bacteriophage Typing of Salmonella. I. Isolation and Host Range Study of Bacteriophages

    PubMed Central

    Ibrahim, Abdel Aziz E.

    1969-01-01

    A series of bacteriophages, lytic for bacteria belonging to the genera Escherichia and Salmonella, were isolated. The phages were isolated from fecal samples, intestinal contents of turkey poults, and carrier cultures of S. typhimurium, S. typhimurium var copenhagen, S. heidelberg, and E. coli. The feasibility of using different habitats as sources of Salmonella phages was evaluated. The carrier cultures were the most promising source for phages active on the serotypes for which the phages were sought. A host range study of the isolated phages was made. Eight phages were selected to develop a phage typing scheme for S. typhimurium, S. typhimurium var copenhagen, and S. heidelberg. PMID:4907005

  20. Neutronic Analyses of the Trade Demonstration Facility

    SciTech Connect

    Rubbia, C.

    2004-09-15

    The TRiga Accelerator-Driven Experiment (TRADE), to be performed in the TRIGA reactor of the ENEA-Casaccia Centre in Italy, consists of the coupling of an external proton accelerator to a target to be installed in the central channel of the reactor scrammed to subcriticality. This pilot experiment, aimed at a global demonstration of the accelerator-driven system concept, is based on an original idea of C. Rubbia. The present paper reports the results of some neutronic analyses focused on the feasibility of TRADE. Results show that all relevant experiments (at different power levels in a wide range of subcriticalities) can be carried out with relatively limited modifications to the present TRIGA reactor.

  1. Differential Host Immune Responses after Infection with Wild-Type or Lab-Attenuated Rabies Viruses in Dogs

    PubMed Central

    Huang, Ying; Li, Zhenguang; Leyson, Christina M.; Cooper, Tanya L.; Platt, Simon R.; Harvey, Stephen B.; Hooper, Douglas C.; Faber, Milosz; Fu, Zhen F.

    2015-01-01

    Rabies virus (RABV) induces encephalomyelitis in humans and animals. One of the major problems with rabies is that the infected individuals most often do not develop virus neutralizing antibodies (VNA). In this study we have investigated the host immune response to RABV infection in dogs, using a live-attenuated (TriGAS) or a wild-type (wt) (DRV-NG11) RABV isolated from a rabid dog. Methodology/Principal Findings The experimental infection of dogs with TriGAS induced high levels of VNA in the serum, whereas wt RABV infection did not. Dogs infected with TriGAS developed antibodies against the virus including its glycoprotein, whereas dogs infected with DRV-NG11 only developed rabies antibodies that are presumably specific for the nucleoprotein, (N) and not the glycoprotein (G). We show that infection with TriGAS induces early activation of B cells in the draining lymph nodes and persistent activation of DCs and B cells in the blood. On the other hand, infection with DRV-NG11 fails to induce the activation of DCs and B cells and further reduces CD4 T cell production. Further, we show that intrathecal (IT) immunization of TriGAS not only induced high levels of VNA in the serum but also in the CSF while intramuscular (IM) immunization of TriGAS induced VNA only in the serum. In addition, high levels of total protein and WBC were detected in the CSF of IT immunized dogs, indicating the transient enhancement of blood-brain barrier (BBB) permeability, which is relevant to the passage of immune effectors from periphery into the CNS. Conclusions/Significance IM infection of dogs with TriGAS induced the production of serum VNA whereas, IT immunization of TriGAS in dogs induces high levels of VNA in the periphery as well as in the CSF and transiently enhances BBB permeability. In contrast, infection with wt DRV-NG11 resulted in the production of RABV-reactive antibodies but VNA and antibodies specific for G were absent. As a consequence, all of the dogs infected with wt DRV

  2. Evaluation of the Telecommunications Protocol Processing Subsystem Using Reconfigurable Interoperable Gate Array

    NASA Technical Reports Server (NTRS)

    Pang, Jackson; Liddicoat, Albert; Ralston, Jesse; Pingree, Paula

    2006-01-01

    The current implementation of the Telecommunications Protocol Processing Subsystem Using Reconfigurable Interoperable Gate Arrays (TRIGA) is equipped with CFDP protocol and CCSDS Telemetry and Telecommand framing schemes to replace the CPU intensive software counterpart implementation for reliable deep space communication. We present the hardware/software co-design methodology used to accomplish high data rate throughput. The hardware CFDP protocol stack implementation is then compared against the two recent flight implementations. The results from our experiments show that TRIGA offers more than 3 orders of magnitude throughput improvement with less than one-tenth of the power consumption.

  3. Impact of litter Salmonella strain on the recovered Salmonella strains from broiler crop and ceca following feed withdrawal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the impact of litter Salmonella status during feed withdrawal, 2 pens of 5-wk-old broilers (n=10/pen) in separate rooms were challenged with marker strains of either Salmonella Montevideo (nalidixic acid resistant) or Salmonella Heidelberg (streptomycin resistant) by oral gavage. Three ...

  4. 3. Anthony Bley, Photographer. September, 1976 L TO R: CORN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Anthony Bley, Photographer. September, 1976 L TO R: CORN CRIB, FRAME OF WHEAT BARN, BARN, MILKSHED - Dundore Farm, State Route 183 & Church Road vicinity, Penn Township (moved to Brownsville vicinity, Lower Heidelberg Township, Berks County), Mount Pleasant, Berks County, PA

  5. 5. Anthony Bley, Photographer Summer, 1975 L TO R: CORN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Anthony Bley, Photographer Summer, 1975 L TO R: CORN CRIB-WAGON SHED, BARN, FRAME OF WHEAT BARN, CORN CRIB, PIG BARN - Dundore Farm, State Route 183 & Church Road vicinity, Penn Township (moved to Brownsville vicinity, Lower Heidelberg Township, Berks County), Mount Pleasant, Berks County, PA

  6. 4. Anthony Bley, Photographer September, 1976 L TO R: CORN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Anthony Bley, Photographer September, 1976 L TO R: CORN CRIB, -WAGON SHED, BARN, FRAME OF WHEAT BARN, CORN CRIB - Dundore Farm, State Route 183 & Church Road vicinity, Penn Township (moved to Brownsville vicinity, Lower Heidelberg Township, Berks County), Mount Pleasant, Berks County, PA

  7. One-Step Identification of Five Prominent Chicken Salmonella Serovars and Biotypes

    PubMed Central

    Zhu, Chunhong; Yue, Min; Rankin, Shelley; Weill, François-Xavier; Frey, Joachim

    2015-01-01

    Based on bacterial genomic data, we developed a one-step multiplex PCR assay to identify Salmonella and simultaneously differentiate the two invasive avian-adapted S. enterica serovar Gallinarum biotypes Gallinarum and Pullorum, and the most frequent, specific, and asymptomatic colonizers of chickens, serovars Enteritidis, Heidelberg, and Kentucky. PMID:26378281

  8. Rapid and early detection of salmonella serotypes with hyperspectral microscope and multivariate data analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to evaluate hyperspectral microscope images for early and rapid detection of Salmonella serotypes: S. Enteritidis, S. Heidelberg, S. Infantis, S. Kentucky, and S. Typhimurium at incubation times of 6, 8, 10, 12, and 24 hours. Images were collected by an acousto-optical tunab...

  9. Detection and classification of salmonella serotypes using spectral signatures collected by fourier transform infrared (FT-IR) spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spectral signatures of Salmonella serotypes namely Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky were collected using Fourier transform infrared spectroscopy (FT-IR). About 5-10 µL of Salmonella suspensions with concentrations of 1...

  10. Mothers with a History of Abuse Tend to Show More Impulsiveness

    ERIC Educational Resources Information Center

    Mohler, E.; Matheis, V.; Poustka, L.; Marysko, M.; Finke, P.; Kaufmann, C.; Reck, C.; Cierpka, M.; Resch, F.

    2009-01-01

    Background: Maternal history of abuse is a postulated risk factor for child maltreatment. However, there have been no case-control studies on maternal impulsiveness in a larger sample of mothers with a history of abuse. Method: Women in the area of Heidelberg giving birth to a child between May 2005 and June 2007 were contacted by mail and…

  11. Thoughts concerning the BMJ editorial "Kitemarking the west wind" and the WHO dot-health proposal

    PubMed Central

    Eysenbach, Gunther

    2000-01-01

    Tony Delamothe has recently written a BMJ editorial [1], which was partly inspired by the MedCERTAIN workshop in Heidelberg. As the initiator and co-ordinator of an EU project, which could be misunderstood as a "kitemarking" project, I feel obliged to clarify what we want to achieve and how and why our approach differs from what is being described by Tony.

  12. Dotty Wotty Collages: Composing with Fiber

    ERIC Educational Resources Information Center

    Sterling, Joan

    2010-01-01

    Tyree Guyton is a popular local hero in Detroit, although it's taken years for him to reach the elite status he now occupies. He's taken inner-city houses and fields--previously rundown and littered with trash--and created controversial art installations, each with deep meaning beyond the visual. Guyton grew up on Heidelberg and Ellery Streets in…

  13. CAPE-OPEN WITH .NET TRAINING COURSE

    EPA Science Inventory

    On March 7, 2007 in Heidelberg, Germany, the CAPE-OPEN Laboratories Network (CO-LaN) is offering a one-day training seminar on implementing CAPE-OPEN compliant process modeling components (PMCs) using .NET-based development tools. This seminar will be geared to component develope...

  14. VizieR Online Data Catalog: Fe7+ ionization cross section (Hahn+,

    NASA Astrophysics Data System (ADS)

    Hahn, M.; Becker, A.; Bernhardt, D.; Grieser, M.; Krantz, C.; Lestinsky, M.; Muller, A.; Novotny, O.; Repnow, R.; Schippers, S.; Spruck, K.; Wolf, A.; Savin, D. W.

    2016-02-01

    Cross-section measurements were carried out using the TSR heavy ion storage ring located at the Max-Planck-Institut fur Kernphysik in Heidelberg, Germany. Additionally, recombination measurements for Fe7+ were performed at TSR by Schmidt et al. (2008A&A...492..265S) using similar methods. (1 data file).

  15. Recalling Karl Jaspers' Classic: The Idea of the University. IHE Perspectives.

    ERIC Educational Resources Information Center

    Fincher, Cameron

    This essay revisits Karl Jaspers' classic, "The Idea of the University." Jaspers was reinstated as president of Heidelberg University in 1945, and he presided over its rebuilding. His book, "The Idea of the University," written in 1946, was published in English 13 years later. It interprets an ideal of the university and emphasizes the purposes…

  16. 78 FR 77115 - Lock 14 Hydro Partners; Notice of Application Ready for Environmental Analysis and Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-20

    ... Energy Regulatory Commission Lock 14 Hydro Partners; Notice of Application Ready for Environmental..., 2012. d. Applicant: Lock 14 Hydro Partners, LLC. e. Name of Project: Heidelberg Dam Hydroelectric... within the project boundary. g. Filed Pursuant to: Federal Power Act, 16 U.S.C. 791(a)-825(r)....

  17. Into the Future by Tradition: Higher Education in the Federal Republic of Germany.

    ERIC Educational Resources Information Center

    Gieseke, Ludwig

    1987-01-01

    Upon the occasion of the University of Heidelberg (the oldest higher education institution in the Federal Republic of Germany) celebration of its 600th anniversary in 1986, this historical overview and current review of higher education in the Federal Republic looks at a wide range of topics. Contents include: "The Historical Growth of Higher…

  18. Adventurous Navigator of the Dimensions of High Ability: An Interview with Robert J. Sternberg

    ERIC Educational Resources Information Center

    Henshon, Suzanna E.

    2008-01-01

    Robert J. Sternberg is Dean of the School of Arts and Sciences, Professor of Psychology, and Adjunct Professor of Education at Tufts University. He also is Honorary Professor of Psychology at the University of Heidelberg, Germany. Prior to joining the faculty at Tufts, he was IBM Professor of Psychology and Education in the Department of…

  19. A comparative study on invasion, survival, modulation of oxidative burst, and nitric oxide responses of macrophages (HD11), and systemic infection in chickens by prevalent poultry Salmonella serovars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poultry is a major reservoir for foodborne Salmonella serovars. Salmonella Typhimurium, S. Enteritidis, S. Heidelberg, S. Kentucky, and S. Senftenberg are the most prevalent serovars in poultry. Information concerning the interactions between different Salmonella species and host cells in poultry i...

  20. Reaching Out to Help Low Income Parents Foster Their Young Children's Literacy Development.

    ERIC Educational Resources Information Center

    Toomey, Derek

    A study examined the effectiveness of the West Heidelberg (Australia) Early Literacy Project (WHELP), which helps low income and working class parents develop the literacy skills of their 4-year-old children by, among other things, reading regularly to them. The project developed through three phases with three different methods of delivering…

  1. Long-Term Effects of a Parent-Based Language Intervention on Language Outcomes and Working Memory for Late-Talking Toddlers

    ERIC Educational Resources Information Center

    Buschmann, Anke; Multhauf, Bettina; Hasselhorn, Marcus; Pietz, Joachim

    2015-01-01

    A randomized control intervention study was conducted to evaluate the effects of the highly structured Heidelberg Parent-Based Language Intervention (HPLI). The outcomes of 43 children (n = 23 intervention, n = 20 control) who had been identified as late talkers during routine developmental check-ups carried out in pediatric practices at the age…

  2. Why is the conclusion of the Gerda experiment not justified

    NASA Astrophysics Data System (ADS)

    Klapdor-Kleingrothaus, H. V.; Krivosheina, I. V.

    2013-12-01

    The first results of the GERDA double beta experiment in Gran Sasso were recently presented. They are fully consistent with the HEIDELBERG-MOSCOW experiment, but because of its low statistics cannot proof anything at this moment. It is no surprise that the statistics is still far from being able to test the signal claimed by the HEIDELBERG-MOSCOW experiment. The energy resolution of the coaxial detectors is a factor of 1.5 worse than in the HEIDELBERG-MOSCOW experiment. The original goal of background reduction to 10-2 counts/kg y keV, or by an order of magnitude compared to the HEIDELBERG-MOSCOW experiment, has not been reached. The background is only a factor 2.3 lower if we refer it to the experimental line width, i.e. in units counts/kg y energy resolution. With pulse shape analysis ( PSA) the back-ground in the HEIDELBERG-MOSCOW experiment around Q ββ is 4 × 10-3 counts/kg y keV [1], which is a factor of 4 (5 referring to the line width) lower than that of GERDA with pulse shape analysis. The amount of enriched material used in the GERDA measurement is 14.6 kg, only a factor of 1.34 larger than that used in the HEIDELBERG-MOSCOW experiment. The background model is oversimplified and not yet adequate. It is not shown that the lines of their background can be identified. GERDA has to continue the measurement further ˜5 years, until they can responsibly present an understood background. The present half life limit presented by GERDA of T {1/2/0v} > 2.1 × 1025 y (90% confidence level, i.e. 1.6ρ) is still lower than the half-life of T {1/2/0v} = 2.23{-0.31/+0.44} × 1025 y [1] determined in the HEIDELBERG-MOSCOW experiment.

  3. 75 FR 36717 - Washington State University; Notice of Acceptance for Docketing and Opportunity for Hearing on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-28

    ... University (the licensee, WSU) to operate the Washington State University Modified TRIGA Nuclear Radiation... NRC E Filing rule (72 FR 49139, August 28, 2007). The E Filing process requires participants to submit... NRC's E Filing Rule (72 FR 49139; August 28, 2007) apply to appeals of NRC staff...

  4. Gamma spectrometric assessment of nuclear fuel

    NASA Astrophysics Data System (ADS)

    Krištof, Edvard; Pregl, Gvido

    1990-12-01

    A description is given of a gamma spectrometric technique which has been developed with the aim of determining the amount of a certain radioactive fission product taking into consideration local variations of the linear attenuation coefficient of gamma rays. Also, an experiment using a fuel element of the TRIGA Mark II reactor in Ljubljana is presented.

  5. 76 FR 62868 - Washington State University; Notice of Issuance of Renewed Facility Operating License No. R-76

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... published in the Federal Register on June 28, 2010 (75 FR 36717-36721). The NRC received no request for a..., 2011 (76 FR 2192821931), and concluded that renewal of the facility operating license will not have a... Modified TRIGA Nuclear Reactor is a pool-type, natural convection, light-water cooled, and shielded...

  6. Ion composition changes during F-region density depletions in the presence of electric fields at auroral latitudes

    NASA Astrophysics Data System (ADS)

    Häggström, I.; Collis, P. N.

    1991-01-01

    The following sections are included: * Introduction * Short description of TRIGA reactors * Calculational model * TRIGAP code * Power (flux) distributions and burnup calculations * Flux and power distribution in mixed core * Burnup calculations in mixed core * Mixed core optimization and fuel management * Optimization of irradiation facilities * Optimization of experiments * Irradiation of power reactor pressure vessel specimens * Conclusions * References

  7. UO 2 fuel behavior under RIA type tests

    NASA Astrophysics Data System (ADS)

    Negut, Gheorghe; Popov, Mircea

    1992-06-01

    This paper describes the test conducted to investigate the failure threshold of the fuel when subjected to RIA, accomplished in the TRIGA ACPR Nuclear Research Institute, Pitesti. The reactor facility, the capsule used in experiments and the experimental results are presented. The failure threshold was determined at 200 cal/g for an atmospheric gap pressure comparable with similar tests.

  8. 77 FR 26321 - Reed College, Reed Research Nuclear Reactor, Renewed Facility Operating License No. R-112

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ... Opportunity for Hearing published in the Federal Register on August 19, 2011 (76 FR 52018- 52022). The NRC... Register on March 30, 2012 (77 FR 19362-19366), and concluded that renewal of the facility operating...-water cooled, and shielded TRIGA (Training, Research, Isotope Production, General Atomics) reactor...

  9. Neutron radiography and neutron-induced autoradiography for the classroom

    SciTech Connect

    Aderhold, H.C. )

    1992-01-01

    The Cornell 500-kW MARK II TRIGA reactor at the Ward Laboratory of Nuclear Engineering has been used to illustrate the application of neutron radiography (NR) and neutron-induced autoradiography (NIAR) for solving problems in engineering as well as problems in art history. The applications are described in the paper.

  10. A Neural Network Model for the Tomographic Analysis of Irradiated Nuclear Fuel Rods

    SciTech Connect

    Craciunescu, Teddy

    2004-04-15

    A tomographic method based on a multilayer feed-forward artificial neural network is proposed for the reconstruction of gamma-radioactive fission product distribution in irradiated nuclear fuel rods. The quality of the method is investigated as compared to a conventional technique on experimental results concerning a Canada deuterium uranium reactor (CANDU)-type fuel rod irradiated in a TRIGA reactor.

  11. Fuel followed control rod installation at AFRRI

    SciTech Connect

    Moore, Mark; Owens, Chris; Forsbacka, Matt

    1992-07-01

    Fuel Followed Control Rods (FFCRs) were installed at the Armed Forces Radiobiology Research Institute's 1 MW TRIGA Reactor. The procedures for obtaining, shipping, and installing the FFCRs is described. As part of the FFCR installation, the transient rod drive was relocated. Core performance due to the addition of the fuel followed control rods is discussed. (author)

  12. Neutron beam characterization at the Neutron Radiography Reactor (NRAD)

    SciTech Connect

    Imel, G.R.; Urbatsch, T.; Pruett, D.P.; Ross, J.R.

    1990-01-01

    The Neutron Radiography Reactor (NRAD) is a 250-kW TRIGA Reactor operated by Argonne National Laboratory and is located near Idaho Falls, Idaho. The reactor and its facilities regarding radiography are detailed in another paper at this conference; this paper summarizes neutron flux measurements and calculations that have been performed to better understand and potentially improve the neutronics characteristics of the reactor.

  13. 77 FR 76601 - Office of Hazardous Materials Safety; Notice of Application for Special Permits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... Matheson Tri-Gas 49 CFR 172.203; To authorize the Basking, Ridge, NJ. 172.301; 172.302; transportation in... containing residue of high flash point combustible liquid. (mode 1) 15769-N KMG Chemicals, 49 CFR 172.102,...

  14. University Reactor Instrumentation Grant

    SciTech Connect

    S. M. Bajorek

    2000-02-01

    A noble gas air monitoring system was purchased through the University Reactor Instrumentation Grant Program. This monitor was installed in the Kansas State TRIGA reactor bay at a location near the top surface of the reactor pool according to recommendation by the supplier. This system is now functional and has been incorporated into the facility license.

  15. Decommissioning of German Research Reactors Under the Governance of the Federal Ministry of Education and Research - 12154

    SciTech Connect

    Weigl, M.

    2012-07-01

    Since 1956, nuclear research and development (R and D) in Germany has been supported by the Federal Government. The goal was to help German industry to become competitive in all fields of nuclear technology. National research centers were established and demonstration plants were built. In the meantime, all these facilities were shut down and are now in a state of decommissioning and dismantling (D and D). Meanwhile, Germany is one of the leading countries in the world in the field of D and D. Two big demonstration plants, the Niederaichbach Nuclear Power Plant (KKN) a heavy-water cooled pressure tube reactor with carbon-dioxide cooling and the Karlstein Superheated Steam Reactor (HDR) a boiling light water reactor with a thermal power of 100 MW, are totally dismantled and 'green field' is reached. Another big project was finished in 2008. The Forschungs-Reaktor Juelich 1 (FRJ1), a research reactor with a thermal power of 10 MW was completely dismantled and in September 2008 an oak tree was planted on a green field at the site, where the FRJ1 was standing before. This is another example for German success in the field of D and D. Within these projects a lot of new solutions and innovative techniques were tested, which were developed at German universities and in small and medium sized companies mostly funded by the Federal Ministry of Education and Research (BMBF). Some examples are underwater-cutting technologies like plasma arc cutting and contact arc metal cutting. This clearly shows that research on the field of D and D is important for the future. Moreover, these research activities are important to save the know-how in nuclear engineering in Germany and will enable enterprises to compete on the increasing market of D and D services. The author assumes that an efficient decommissioning of nuclear installations will help stabilize the credibility of nuclear energy. Some critics of nuclear energy are insisting that a return to 'green field sites' is not possible

  16. Development of an accommodative smartphone app for medical guidelines in pediatric emergencies.

    PubMed

    Schmucker, Michael; Heid, Jörn; Haag, Martin

    2014-01-01

    One of the outcomes of a training concept for physicians and nurses concerning pediatric emergencies at the Heidelberg University Hospital was that the work and procedures in childhood emergencies could be simplified by replacing the existing paper-based guidelines with a smartphone app. Since the project funds for this were already used up, a group of students from the master program "Medical Informatics" of Heidelberg and Heilbronn Universities took over the development of the app. Particular attention was given to the need for compatibility with the variety of devices (device size and screen resolution) and platform independence. The guidelines themselves were scripted in HTML5, JavaScript and CSS (responsive web design); managed by a container programmed in Sencha Touch. Even though the app is not yet available in the App-Store due to the limited timeframe, the students gained a great deal of valuable experience in developing platform independent software for mobile devices. PMID:24825689

  17. The ESPRI Project: differential delay lines for PRIMA

    NASA Astrophysics Data System (ADS)

    Pepe, F.; Queloz, D.; Henning, Th.; Quirrenbach, A.; Delplancke, F.; Andolfato, L.; Baumeister, H.; Bizenberger, P.; Bleuler, H.; Chazelas, B.; Dérie, F.; Di Lieto, L.; Duc, T. P.; Duvanel, O.; Fleury, M.; Gillet, D.; Graser, U.; Koch, F.; Launhardt, R.; Maire, C.; Mégevand, D.; Michellod, Y.; Moresmau, J.-M.; Müllhaupt, P.; Naranjo, V.; Sache, L.; Salvadé, Y.; Simond, G.; Sosnowska, D.; Wagner, K.; Zago, L.

    2008-07-01

    ESPRI is a project which aims at searching for and characterizing extra-solar planets by dual-beam astrometry with PRIMA@VLTI. Differential Delay Lines (DDL) are fundamental for achieving the micro-arcseconds accuracy required by the scientific objective. Our Consortium, consisting of the Geneva Observatory, the Max-Planck Institut for Astronomy Heidelberg, and the Landessternwarte Heidelberg, in collaboration with ESO, has built and tested these DDLs successfully and will install them in summer 2008 at the VLTI. These DDLs consist of high quality cat's eyes displaced on a parallel beam-mechanics and by means of a two-stage actuation with a precision of 5 nm over a stroke length of 70 mm. Over the full range, a bandwidth of about 400 Hz is achieved. The DDLs are operated in vacuum. We shall present, in this paper, their design and their exceptional performances.

  18. [Moleschott and materialism].

    PubMed

    van Gijn, Jan; Gijselhart, Joost P

    2012-01-01

    Jacques Moleschott (1822-1893), born into a Dutch Roman Catholic family, attended secondary school in Cleve (Germany). There he became captivated by Hegelian philosophy and lost his faith. After medical studies in Heidelberg and a brief spell as physician in Utrecht, where he struck up a life-long friendship with the physiologists Franciscus Donders (1818-1889) and Izaak van Deen (1805-1869), he returned to Heidelberg as lecturer in physiology. In his textbooks and particularly in his book for the general public, 'The circulation of life' (in German), he attested to a strict physicochemical view of biological phenomena, in opposition to contemporary notions of vitalism and teleology. When the atheistic implications had caused a conflict with the authorities in Baden, he moved as professor of physiology to Zürich (1854) and subsequently to the emerging nation of Italy, as professor in Turin (1861) and finally in Rome (1878), where he became a senator. PMID:22929747

  19. Detection and analysis of two serotypes of ammonia-oxidizing bacteria in sewage plants by flow cytometry.

    PubMed Central

    Völsch, A; Nader, W F; Geiss, H K; Nebe, G; Birr, C

    1990-01-01

    Two different serotypes of the genus Nitrosomonas were isolated from samples of the sewage plant Heidelberg. These nitrifiers were enumerated in activated sludge of various other sewage plants after immunofluorescent labeling and staining with propidium iodide by flow cytometry. The concentrations of these serotypes of Nitrosomonas spp. were in the range of 0.1 to 2%. Also, a test for the determination of the activity of ammonia-oxidizing bacteria was developed. Nitrite-oxidizing bacteria were specifically inhibited with sodium chlorate, and the activity of ammonia-oxidizing bacteria could be calculated from the increase of nitrite. Concentrations and activities of ammonia oxidizers were measured for a period of 6 months in the sewage plant Heidelberg. With one exception, activities and concentrations of ammonia-oxidizing bacteria decreased and increased in parallel. PMID:2403253

  20. Spectral-Domain Optical Coherence Tomography, Wide-Field Photography, and Fundus Autofluorescence Correlation of Posterior Ophthalmomyiasis Interna.

    PubMed

    Paulus, Yannis M; Butler, Nicholas J

    2016-07-01

    Posterior ophthalmomyiasis interna is a rare, potentially devastating infestation of the posterior segment by fly larvae. The authors report the first demonstration of spectral-domain optical coherence tomography (SD-OCT) (Spectralis; Heidelberg Engineering, Heidelberg, Germany), wide-field angiography (Optos, Dunfermline, Scotland) and photography, and fundus autofluorescence with temporal progression during a period of 6 months. A 12-year-old white female presented with acute, painless vision loss with hand motions visual acuity. No larva was visible, so she was treated with oral ivermectin. Visual acuity improved to 20/80. OCT demonstrated hyporeflective spaces of the outer retina and retinal pigment epithelium, which resolved during 1-month period with improved ellipsoid layer by 6 months. Fundus autofluorescence demonstrated linear hypoautofluorescent tracks. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:682-685.]. PMID:27434903

  1. TOP500 Supercomputers for June 2004

    SciTech Connect

    Strohmaier, Erich; Meuer, Hans W.; Dongarra, Jack; Simon, Horst D.

    2004-06-23

    23rd Edition of TOP500 List of World's Fastest Supercomputers Released: Japan's Earth Simulator Enters Third Year in Top Position MANNHEIM, Germany; KNOXVILLE, Tenn.;&BERKELEY, Calif. In what has become a closely watched event in the world of high-performance computing, the 23rd edition of the TOP500 list of the world's fastest supercomputers was released today (June 23, 2004) at the International Supercomputer Conference in Heidelberg, Germany.

  2. TOP500 Supercomputers for June 2005

    SciTech Connect

    Strohmaier, Erich; Meuer, Hans W.; Dongarra, Jack; Simon, Horst D.

    2005-06-22

    25th Edition of TOP500 List of World's Fastest Supercomputers Released: DOE/L LNL BlueGene/L and IBM gain Top Positions MANNHEIM, Germany; KNOXVILLE, Tenn.; BERKELEY, Calif. In what has become a closely watched event in the world of high-performance computing, the 25th edition of the TOP500 list of the world's fastest supercomputers was released today (June 22, 2005) at the 20th International Supercomputing Conference (ISC2005) in Heidelberg Germany.

  3. Dr Alexander Graham Bell--audiologist and speech therapist.

    PubMed

    Chakravorty, R C

    1976-09-01

    Alexander Graham Bell is best known for his role in the invention of the telephone. However, he had a lifelong involvement in speech therapy and audiology besides many other medical investigations. He was also awarded an honorary MD degree from Heidelberg University. In this, the 100th anniversary of his invention of the telephone, his life and some of his medical interests are briefly reviewed. PMID:786234

  4. State-Selective Quantum Interference Observed in the Recombination of Highly Charged Hg{sup 75+{center_dot}}{sup {center_dot}}{sup {center_dot}}{sup 78+} Mercury Ions in an Electron Beam Ion Trap

    SciTech Connect

    Gonzalez Martinez, A.J.; Lopez-Urrutia, J.R. Crespo; Braun, J.; Brenner, G.; Bruhns, H.; Lapierre, A.; Mironov, V.; Soria Orts, R.; Tawara, H.; Trinczek, M.; Ullrich, J.; Scofield, J.H.

    2005-05-27

    We present experimental data on the state-selective quantum interference between different pathways of photorecombination, namely, radiative and dielectronic recombination, in the KLL resonances of highly charged mercury ions. The interference, observed for well resolved electronic states in the Heidelberg electron beam ion trap, manifests itself in the asymmetry of line shapes, characterized by ''Fano factors,'' which have been determined with unprecedented precision, as well as their excitation energies, for several strong dielectronic resonances.

  5. Kirchhoff, Gustav Robert (1824-87)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Born in Königsberg, Prussia (now Kaliningrad, Russia), became professor of physics at Heidelberg where he collaborated with Bunsen, later professor in Berlin. With Kirchhoff's laws of electricity he extended the work of Ohm. He worked on black-body radiation and spectrum analysis. With Kirchhoff's laws of radiation he explained the dark lines in the Sun's spectrum as caused by absorption of parti...

  6. Laser and electron cooling of relativistic stored beams

    SciTech Connect

    Huber, G.; Schroeder, S.; Klein, R.; Boos, N.; Grieser, R.; Hoog, I.; Krieg, M.; Merz, P. ); Kuehl, T.; Neumann, R. ); Balykin, V.; Grieser, M.; Habs, D.; Jaeschke, E.; Petrich, W.; Schwalm, D.; Steck, M.; Wanner, B.; Wolf, A. )

    1991-08-05

    Laser cooling of ions at relativistic energies was first observed at the TSR storage ring in Heidelberg. A {sup 7}Li{sup +} ion beam moving at 6.4% the speed of light was overlapped with resonant co- and counter-propagating laser beams. The longitudinal temperatures were found to pass below 190 mK. Limits and applications of laser cooled relativistic ion beams are discussed. Laser cooling and electron cooling of the ion beam were combined.

  7. The LEECH Exoplanet Imaging Survey. Further constraints on the planet architecture of the HR 8799 system (Corrigendum)

    NASA Astrophysics Data System (ADS)

    Maire, A.-L.; Skemer, A. J.; Hinz, P. M.; Desidera, S.; Esposito, S.; Gratton, R.; Marzari, F.; Skrutskie, M. F.; Biller, B. A.; Defrère, D.; Bailey, V. P.; Leisenring, J. M.; Apai, D.; Bonnefoy, M.; Brandner, W.; Buenzli, E.; Claudi, R. U.; Close, L. M.; Crepp, J. R.; De Rosa, R. J.; Eisner, J. A.; Fortney, J. J.; Henning, T.; Hofmann, K.-H.; Kopytova, T. G.; Males, J. R.; Mesa, D.; Morzinski, K. M.; Oza, A.; Patience, J.; Pinna, E.; Rajan, A.; Schertl, D.; Schlieder, J. E.; Su, K. Y. L.; Vaz, A.; Ward-Duong, K.; Weigelt, G.; Woodward, C. E.

    2015-07-01

    The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.

  8. Central diffractive resonance production at the LHC

    NASA Astrophysics Data System (ADS)

    Fiore, Roberto; Jenkovszky, Laszlo; Schicker, Rainer

    2016-07-01

    Central production of resonances resulting from the scattering of Pomerons in the central rapidity region of proton-proton scattering is studied. Estimates for relevant cross sections are presented. L.J. gratefully acknowledges an EMMI visiting Professorship at the University of Heidelberg for completion of this work. He is grateful to the organizers of this meeting for their hospitality and support. His work was supported also by DOMUS, Hungarian Academy of Sciences

  9. Performance of the LINC NIRVANA fringe and flexure tracker at delivery

    NASA Astrophysics Data System (ADS)

    Horrobin, Matthew; Eckart, Andreas; Beckmann, Udo; Connot, Claus; Dierkes, Jens; Lindhorst, Bettina; Nußbaum, Edmund; Rost, Steffen; Smajić, Semir; Straubmeier, Christian; Wank, Imke; Bertram, Thomas; Pott, Jörg-Uwe

    2014-07-01

    The LINC-NIRVANA Fringe and Flexure Tracking System has nearly completed assembly in the lab in Cologne, and will soon be ready for shipment and integration into the full LINC-NIRVANA system at MPIA Heidelberg. This paper provides an overview of the final assembly and testing phase in Cologne, concentrating on those aspects that directly affect instrument performance, including the detector performance and stability of the detector positioning system.

  10. Longitudinal Change Detected by Spectral Domain Optical Coherence Tomography in the Optic Nerve Head and Peripapillary Retina in Experimental Glaucoma

    PubMed Central

    Strouthidis, Nicholas G.; Fortune, Brad; Yang, Hongli; Sigal, Ian A.

    2011-01-01

    Purpose. To investigate whether longitudinal changes deep within the optic nerve head (ONH) are detectable by spectral domain optical coherence tomography (SDOCT) in experimental glaucoma (EG) and whether these changes are detectable at the onset of Heidelberg Retina Tomography (HRT; Heidelberg Engineering, Heidelberg, Germany)–defined surface topography depression. Methods. Longitudinal SDOCT imaging (Spectralis; Heidelberg Engineering) was performed in both eyes of nine rhesus macaques every 1 to 3 weeks. One eye of each underwent trabecular laser-induced IOP elevation. Four masked operators delineated internal limiting membrane (ILM), retinal nerve fiber layer (RNFL), Bruch's membrane/retinal pigment epithelium (BM/RPE), neural canal opening (NCO), and anterior lamina cribrosa surface (ALCS) by using custom software. Longitudinal changes were assessed and compared between the EG and control (nonlasered) eyes at the onset of HRT-detected surface depression (follow-up 1; [FU1]) and at the most recent image (follow-up 2; [FU2]). Results. Mean IOP in EG eyes was 7.1 to 24.6 mm Hg at FU1 and 13.5 to 31.9 mm Hg at FU2. In control eyes, the mean IOP was 7.2 to 12.6 mm Hg (FU1) and 8.9 to 16.0 mm Hg (FU2). At FU1, neuroretinal rim decreased and ALCS depth increased significantly (paired t-test, P < 0.01); no change in RNFL thickness was detected. At FU2, however, significant prelaminar tissue thinning, posterior displacement of NCO, and RNFL thinning were observed. Conclusions. Longitudinal SDOCT imaging can detect deep ONH changes in EG eyes, the earliest of which are present at the onset of HRT-detected ONH surface height depression. These parameters represent realistic targets for SDOCT detection of glaucomatous progression in human subjects. PMID:21217108

  11. [Experimental transmission of antibiotic resistance in chicks].

    PubMed

    Todorov, T; Todorova, P; Kokosharov, T

    1977-01-01

    Multi-drug resistance of Salmonella heidelberg was transmitted to normal intestinal flora (E. coli organisms were resistant to ampicillin, streptomycin, tetracycline, erythromycin, and oleandomycin. The donor strains of Salmonella heidelberg used in the experiment was a carrier of the following nine markers of resistance: ampicillin, streptomycin, chloramphenicol, kanamycin, neomycin, novobiocin, tetracycline, erythromycin, and oleandomycin. The donor strains of Salmonella heidelberg used in the experiment was a carrier of the following nine markers of resistance: ampicillin, streptomycin, chloramphenicol, kanamycin, neomycin, novobiocin, tetracycline, erythromycin, and oeandomycin, novobiocin, tetracycline, erythromycin, and oleandomycin. The resistance to drugs was transmitted with the oral administration of the donor strain at the preliminary neutralization of the action of hydrochloric acid in the stomah secretion through sodium bicarbonate (1 cm3 of a 10 per cent sol.) an hour prior to feeding the birds with Salmonella heidelberg (1 cm3 of 10(10). In other experiments carboneum tetrachloratum was injected at rates of 0.08 to 0.15 cm3 (acocrting with the body weight of birds) one day prior to infection, followed by the administration of 0.20 to 0.40 cm3 of a 2 per cent solution of omnopon. Escherichia coli organisms acquired new markers of resistance--to chloramphenicol, kanamycin, neomycin and novobiocin. The level of resistance proved equal with that to the donor strain. A total of 1.8 to 5.4 per cent of the intestinal E. coli investigated proved to be carriers of the indicated markers of resitance. Highest level in acquiring markers of multi-drug resistance (13 per cent) showed E. coli organisms isolated from the liver of birds injected additionally with C. tetrachloratum omnopon. PMID:337646

  12. From proteases to proteomics

    PubMed Central

    Neurath, Hans

    2001-01-01

    This personal and professional autobiography covers the 50-yr period of 1950–2000 and includes the following topics: History of the University of Washington School of Medicine and its Department of Biochemistry (Mount Rainier and the University of Washington, recruiting faculty, biology, research programs); scientific editing (publication, Biochemistry, Protein Science, electronic publication); Europe revisited (Heidelberg, approaching retirement, the German Research Center, reunion in Vienna); and 50 yr of research on proteolytic enzymes (trypsin, carboxypeptidases, mast cell proteases, future developments). PMID:11274481

  13. Vibrational Level Structures of the Ground Electronic States of the C_3-Ar and C_3-Ne Complexes

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Ren; Hsu, Yen-Chu

    2014-06-01

    The Heidelberg multiconfiguration time-dependent Hartree package was used. to calculate the vibrational level structures of the ground electronic states of the C_3-Ar and C_3-Ne complexes. The previously reported 4-D ab initio potentials were converted to 6-D potentials by adding the potential energies of the C-C symmetric and antisymmetric stretching vibrations of C_3. They were subsequently transformed from internal coordinates to Jacobi coordinates. The kinetic-energy operators were taken from Yang and Kühn. Preliminary results show that large amplitude motions occur in five coordinates: C-C-C bond angle, out-of-plane tilt angle, van der Waals stretch, van der Waals bend and one of the C-C bonds. G.A. Worth, M.H. Beck, A. Jäckle, H.-D. Meyer, F. Otto, M. Brill, and O. Vendrell, The MCTDH package, version 8.4, Heidelberg University, Heidelberg, Germany, 2011. Y. Yang and O. Kühn, Mol. Phys., 106, 2445 (2008)

  14. The European experience in neutron therapy at the end of 1981

    SciTech Connect

    Wambersie, A.

    1982-12-01

    A survey is presented of the European neutron therapy facilities. For head and neck tumors, the excellent results reported from Hammersmith were not confirmed by a EORTC combined trial (Amsterdam, Edinburgh and Essen). For salivary glands, high percentages (75%) of local control were obtained in Hammersmith and in Amsterdam, as well as in other centers. Following the promising results reported from Hammersmith, neutron therapy of soft tissue sarcomas was started in several centers. For patients with no clinical evidence of residual tumor after surgery, a local control rate ranging between 70% and 90% was achieved (Essen, Hamburg, Heidelberg, Louvain-la-Neuve). For patients with ''gross'' residual tumor, or with inoperable tumors, the percentages of local control vary within large limits (20-75%) from center to center, probably according to differences in histology, tumor localization, tumor size or extention, and perhaps fractionation (Hammersmith, Edinburg, Amsterdam, Essen, Hamburg, Heidelberg, Louvain-la-Neuve). A study on bronchus carcinoma, performed in Heidelberg, did not show any benefit with neutron therapy. Patients with locally extended cervix and prostate carcinoma were treated in Louvain-la-Neuve according to the RTOG protocol; an excellent early tolerance was noticed. However, for both sites, it is too early to derive valid long term conclusions. For prostatic tumors, a complete regression is usually achieved. For bladder carcinoma, the results from Manchester did not indicate a significant difference between neutron and photon therapy, both in initial assessment of results and complications. The Amsterdam group came to similar conclusions.

  15. The European experience in neutron therapy at the end of 1981

    SciTech Connect

    Wambersie, A.

    1982-12-01

    A survey is presented of the European neutron therapy facilities. For head and neck tumors, the excellent results reported from Hammersmith were not confirmed by an EORTC combined trial (Amsterdam, Edinburgh and Essen). For salivary glands, high percentages (75%) of local control were obtained in Hammersmith and in Amsterdam, as well as in other centers. Following the promising results reported from Hammersmith, neutron therapy of soft tissue sarcomas was started in several centers. For patients with no clinical evidence of residual tumor after surgery, a local control rate ranging between 70% and 90% was achieved (Essen, Hamburg, Heidelberg, Louvain-la-Neuve). For patients with ''gross'' residual tumor, or with inoperable tumors, the percentages of local control vary within large limits (20-75%) from center to center, probably according to differences in histology, tumor localization, tumor size or extention, and perhaps fractionation (Hammersmith, Edinburg, Amsterdam, Essen, Hamburg, Heidelberg, Louvain-la-Neuve). A study on bronchus carcinoma, performed in Heidelberg, did not show any benefit with neutron therapy. Patients with locally extended cervix and prostate carcinoma were treated in Louvain-la-Neuve according to the RTOG protocol; an excellent early tolerance was noticed. However, for both sites, it is too early to derive valid long term conclusions. For prostatic tumors, a complete regression is usually achieved. For bladder carcinoma, the results from Manchester did not indicate a significant difference between neutron and photon therapy, both in initial assessment of results and complications. The Amsterdam group came to similar conclusions.

  16. NEUTRON RADIOGRAPHY (NRAD) REACTOR 64-ELEMENT CORE UPGRADE

    SciTech Connect

    John D. Bess

    2014-03-01

    The neutron radiography (NRAD) reactor is a 250 kW TRIGA (registered) (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The interim critical configuration developed during the core upgrade, which contains only 62 fuel elements, has been evaluated as an acceptable benchmark experiment. The final 64-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (approximately +/-1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

  17. MCNP study for epithermal neutron irradiation of an isolated liver at the Finnish BNCT facility.

    PubMed

    Kotiluoto, P; Auterinen, I

    2004-11-01

    A successful boron neutron capture treatment (BNCT) of a patient with multiple liver metastases has been first given in Italy, by placing the removed organ into the thermal neutron column of the Triga research reactor of the University of Pavia. In Finland, FiR 1 Triga reactor with an epithermal neutron beam well suited for BNCT has been extensively used to irradiate patients with brain tumors such as glioblastoma and recently also head and neck tumors. In this work we have studied by MCNP Monte Carlo simulations, whether it would be beneficial to treat an isolated liver with epithermal neutrons instead of thermal ones. The results show, that the epithermal field penetrates deeper into the liver and creates a build-up distribution of the boron dose. Our results strongly encourage further studying of irradiation arrangement of an isolated liver with epithermal neutron fields. PMID:15308144

  18. Investigation of the basic reactor physics characteristics of the Dalat Nuclear Research Reactor

    SciTech Connect

    Huy, N.Q.; Thong, H.V.; Khang, N.P.

    1994-12-31

    The Dalat nuclear research reactor was reconstructed from the TRIGA Mark II reactor, built in 1963 with a nominal power of 250 kW, and reached its planned nominal power of 500 kW for the first time in February 1984. The Dalat reactor has some characteristics distinct from the former TRIGA reactor. Investigation of its characteristics is carried out by the determination of the reactor physics parameters. This paper represents the experimental results obtained for the effective fraction of the delayed photoneutrons, the extraneous neutron source left after the reactor is shut down, the lowest power levels of reactor critical states, the relative axial and radial distributions of thermal neutrons, the safe positive reactivity inserted into the reactor at a deep subcritical state, the reactivity temperature coefficient of water, the temperature on the surface of the fuel elements, etc.

  19. Update on Y-12 national security complex activities to recover enriched uranium in 2007

    SciTech Connect

    Eddy, Becky; Andes, Trent; Dunavant, Randy

    2008-07-15

    During Calendar Year 2007, the Y-12 National Security Complex (Y-12) has completed recovery missions that resulted in the return of highly enriched uranium from Canada and several locations within the United States. These missions were performed in support of the National Nuclear Security Administration's Global Threat Reduction Initiative (GTRI) and the Department of Energy (DOE) Central Scrap Management Office for Uranium (U-CSMO). Additionally, Y-12 completed safety basis revisions for the ES-3100 shipping package which resulted in the issuance of a Certificate of Compliance (CoC) from the United States Nuclear Regulatory Commission and a Competent Authority Certificate (CAC) from the United States Department of Transportation for air transport of highly enriched uranium in the form of un- irradiated TRIGA pellets. This certification of the ES-3100 will now allow GTRI to perform recoveries of limited quantities of fresh HEU TRIGA that have been identified at several locations. (author)

  20. Evaluation of a Reactor On-Line Uncertainty Monitoring System

    SciTech Connect

    Edwards, Robert M.; He, Weidong

    2001-06-17

    Robust control designs were developed to better match experimental conditions available in the TRIGA reactor. A first-order weighting function is specified for each operating range in the robust design to limit the maximum tracking error. Inclusion of the performance-weighting function as the on-line filter is discussed as a possible on-line performance-monitoring method. The scheme to evaluate an on-line uncertainty monitoring system for a robust reactor controller is shown. TRIGA reactor experiments were conducted to evaluate on-line performance-monitoring techniques. It is concluded that the observed robust-control performance-monitoring characteristics can be incorporated in an on-line decision-making process to choose appropriate robust control selection and enforcement.

  1. Hybrid Reactor Simulation and 3-D Information Display of BWR Out-of-Phase Oscillation

    SciTech Connect

    Edwards, Robert; Huang, Zhengyu

    2001-06-17

    The real-time hybrid reactor simulation (HRS) capability of the Penn State TRIGA reactor has been expanded for boiling water reactor (BWR) out-of-phase behavior. During BWR out-of-phase oscillation half of the core can significantly oscillate out of phase with the other half, while the average power reported by the neutronic instrumentation may show a much lower amplitude for the oscillations. A description of the new HRS is given; three computers are employed to handle all the computations required, including real-time data processing and graph generation. BWR out-of-phase oscillation was successfully simulated. By adjusting the reactivity feedback gains from boiling channels to the TRIGA reactor and to the first harmonic mode power simulation, limit cycle can be generated with both reactor power and the simulated first harmonic power. A 3-D display of spatial power distributions of fundamental mode, first harmonic, and total powers over the reactor cross section is shown.

  2. Foreign research reactor irradiated nuclear fuel inventories containing HEU and LEU of United States origin

    SciTech Connect

    Matos, J.E.

    1994-12-01

    This report provides estimates of foreign research reactor inventories of aluminum-based and TRIGA irradiated nuclear fuel elements containing highly enriched and low enriched uranium of United States origin that are anticipated in January 1996, January 2001, and January 2006. These fuels from 104 research reactors in 41 countries are the same aluminum-based and TRIGA fuels that were eligible for receipt under the Department of Energy`s Offsite Fuels Policy that was in effect in 1988. All fuel inventory and reactor data that were available as of December 1, 1994, have been included in the estimates of approximately 14,300 irradiated fuel elements in January 1996, 18,800 in January 2001, and 22,700 in January 2006.

  3. An experimental investigation of 235 sub UF sub 6 fission produced plasmas. [gas handling system for use with nuclear pumped laser experiments

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1981-01-01

    A gas handling system capable of use with uranium fluoride was designed and constructed for use with nuclear pumped laser experiments using the TRIGA research reactor. By employing careful design and temperature controls, the UF6 can be first transported into the irradiation chamber, and then, at the conclusion of the experiment, returned to gas cylinders. The design of the system is described. Operating procedures for the UF6 and gas handling systems are included.

  4. Determination of neutron absorbed doses in lithium aluminates.

    PubMed

    Delfín Loya, A; Carrera, L M; Ureña-Núñez, F; Palacios, O; Bosch, P

    2003-04-01

    Lithium-based ceramics have been proposed as tritium breeders for fusion reactors. The lithium aluminate (gamma phase) seems to be thermally and structurally stable, the damages produced by neutron irradiation depend on the absorbed dose. A method based on the measurement of neutron activation of foils through neutron capture has been developed to obtain the neutron absorbed dose in lithium aluminates irradiated in the thermal column facility and in the fixed irradiation system of a Triga Mark III Nuclear Reactor. PMID:12672632

  5. Design and characterization of an irradiation facility with real-time monitoring

    NASA Astrophysics Data System (ADS)

    Braisted, Jonathan David

    Radiation causes performance degradation in electronics by inducing atomic displacements and ionizations. While radiation hardened components are available, non-radiation hardened electronics can be preferable because they are generally more compact, require less power, and less expensive than radiation tolerant equivalents. It is therefore important to characterize the performance of electronics, both hardened and non-hardened, to prevent costly system or mission failures. Radiation effects tests for electronics generally involve a handful of step irradiations, leading to poorly-resolved data. Step irradiations also introduce uncertainties in electrical measurements due to temperature annealing effects. This effect may be intensified if the time between exposure and measurement is significant. Induced activity in test samples also complicates data collection of step irradiated test samples. The University of Texas at Austin operates a 1.1 MW Mark II TRIGA research reactor. An in-core irradiation facility for radiation effects testing with a real-time monitoring capability has been designed for the UT TRIGA reactor. The facility is larger than any currently available non-central location in a TRIGA, supporting testing of larger electronic components as well as other in-core irradiation applications requiring significant volume such as isotope production or neutron transmutation doping of silicon. This dissertation describes the design and testing of the large in-core irradiation facility and the experimental campaign developed to test the real-time monitoring capability. This irradiation campaign was performed to test the real-time monitoring capability at various reactor power levels. The device chosen for characterization was the 4N25 general-purpose optocoupler. The current transfer ratio, which is an important electrical parameter for optocouplers, was calculated as a function of neutron fluence and gamma dose from the real-time voltage measurements. The

  6. Genetic effects induced by neutrons in Drosophila melanogaster I. Determination of absorbed dose.

    PubMed

    Delfin, A; Paredes, L C; Zambrano, F; Guzmán-Rincón, J; Ureña-Nuñez, F

    2001-12-01

    A method to obtain the absorbed dose in Drosophila melanogaster irradiated in the thermal column facility of the Triga Mark III Reactor has been developed. The method is based on the measurements of neutron activation of gold foils produced by neutron capture to obtain the neutron fluxes. These fluxes, combined with the calculations of kinetic energy released per unit mass, enables one to obtain the absorbed doses in Drosophila melanogaster. PMID:11761104

  7. Trace elements in the diets of Turkish children determined by INAA

    SciTech Connect

    Aras, N.K. ); Mauerhofer, E.; Naidu, R.K.; Arcasoy, A.; Denschlag, H.O.

    1992-01-01

    The role of toxic and essential trace elements in human diet is increasingly important because of environmental problems and the increasingly sophisticated industrial treatment of food products. Instrumental neutron activation analysis (INAA) is particularly well suited for multielement determinations. In order to test and demonstrated the usefulness of the method in connection with the fast pneumatic tube system of the Mainz TRIGA reactor, the authors have analyzed six diet samples of Turkish children.

  8. The analysis of failed nuclear fuel rods by gamma computed tomography

    NASA Astrophysics Data System (ADS)

    Dobrin, Relu; Craciunescu, Teddy; Tuturici, Ioan Liviu

    1997-07-01

    The failure of the cladding of an irradiated nuclear fuel rod can lead to the loss of some γ-radioactive fission products. Consequently the distribution of these fission products is altered in the cross-section of the fuel rod. The modification of the distribution, obtained by gamma computed tomography, is used to determine the integrity of the fuel cladding. The paper reports an experimental result, obtained for a CANDU-type fuel rod, irradiated in a TRIGA 14 MWth reactor.

  9. University Reactor Conversion Lessons Learned Workshop for Texas A&M University Nuclear Science Center Reactor

    SciTech Connect

    Eric C. Woolstenhulme; Dana M. Meyer

    2007-04-01

    The objectives of this meeting were to capture the observations, insights, issues, concerns, and ideas of those involved in the Texas A&M University Nuclear Science Center (TAMU NSC) TRIGA Reactor Conversion so that future efforts can be conducted with greater effectiveness, efficiency, and with fewer challenges. This workshop was held in conjunction with a similar workshop for the University of Florida Reactor Conversion. Some of the generic lessons from that workshop are included in this report for completeness.

  10. EMPLACEMENT DRIFT SHIELDING CALCULATION

    SciTech Connect

    A. Nielsen

    1999-10-13

    The purpose of this analysis is to determine the structural response of a TRIGA Department of Energy (DOE) spent nuclear fuel (SNF) codisposal canister placed in a 5-Defense High Level Waste (DHLW) waste package (WP) and subjected to a tipover design basis event (DBE) dynamic load; the results will be reported in terms of displacements and stress magnitudes. This activity is associated with the WP design.

  11. Research reactors - an overview

    SciTech Connect

    West, C.D.

    1997-03-01

    A broad overview of different types of research and type reactors is provided in this paper. Reactor designs and operating conditions are briefly described for four reactors. The reactor types described include swimming pool reactors, the High Flux Isotope Reactor, the Mark I TRIGA reactor, and the Advanced Neutron Source reactor. Emphasis in the descriptions is placed on safety-related features of the reactors. 7 refs., 7 figs., 2 tabs.

  12. University Reactor Sharing Program. Final report, September 30, 1992--September 29, 1994

    SciTech Connect

    Wehring, B.W.

    1995-01-01

    Over the past 20 years, the number of nuclear reactors on university campuses in the US declined from more than 70 to less than 40. Contrary to this trend, The University of Texas at Austin constructed a new reactor facility at a cost of $5.8 million. The new reactor facility houses a new TRIGA Mark II reactor which replaces an in-ground TRIGA Mark I reactor located in a 50-year old building. The new reactor facility was constructed to strengthen the instruction and research opportunities in nuclear science and engineering for both undergraduate and graduate students at The University of Texas. On January 17, 1992, The University of Texas at Austin received a license for operation of the new reactor. Initial criticality was achieved on March 12, 1992, and full power operation, on March 25, 1992. The UT-TRIGA research reactor provides hands-on education, multidisciplinary research and unique service activities for academic, medical, industrial, and government groups. Support by the University Reactor Sharing Programs increases the availability of The University of Texas reactor facility for use by other educational institutions which do not have nuclear reactors.

  13. Design of an irradiation facility with a real-time radiation effects monitoring capability

    NASA Astrophysics Data System (ADS)

    Braisted, J.; Schneider, E.; O'Kelly, S.; van der Hoeven, C.

    2011-12-01

    An in-core irradiation facility for radiation effects testing with a real-time monitoring capability has been designed for the 1.1 MW TRIGA Mark II research reactor at The University of Texas at Austin. The facility is larger than any currently available non-central location in a TRIGA, supporting testing of larger electronic components as well as other in-core irradiation applications requiring significant volume such as isotope production or neutron transmutation doping of silicon. This article presents the layout and characterization of the large in-core irradiation facility and the real-time electronics performance monitoring capability it is designed to support. To demonstrate this capability, an experimental campaign was conducted where the real-time current transfer ratio for 4N25 general-purpose optocouplers was obtained from in-situ voltage measurements. The resultant radiation effects data - current transfer ratio as a function of neutron and gamma dose - was seen to be repeatable and exceptionally finely resolved. Therefore, the real-time capability at UT TRIGA appears competitive with other effects characterization facilities in terms of number and size of testable samples while additionally offering a novel real-time, in-core monitoring capability.

  14. Investigation of the low enrichment conversion of the Texas A and M Nuclear Science Center Reactor

    SciTech Connect

    Reuscher, J.A.

    1988-01-01

    The use of highly enriched uranium as a fuel research reactors is of concern due to the possibility of diversion for nuclear weapons applications. The Texas A M TRIGA reactor currently uses 70% enriched uranium in a FLIP (Fuel Life Improvement Program) fuel element manufactured by General Atomics. Thus fuel also contains 1.5 weight percent of erbium as a burnable poison to prolong useful core life. US university reactors that use highly enriched uranium will be required to covert to 20% or less enrichment to satisfy Nuclear Regulatory Commission requirements for the next core loading if the fuel is available. This investigation examined the feasibility of a material alternate to uranium-zirconium hydride for LEU conversion of a TRIGA reactor. This material is a beryllium oxide uranium dioxide based fuel. The theoretical aspects of core physics analyses were examined to assess the potential advantages of the alternative fuel. A basic model was developed for the existing core configuration since it is desired to use the present fuel element grid for the replacement core. The computing approach was calibrated to the present core and then applied to a core of BeO-UO{sub 2} fuel elements. Further calculations were performed for the General Atomics TRIGA low-enriched uranium zirconium hydride fuel.

  15. Korea Research Reactor -1 & 2 Decommissioning Project in Korea

    SciTech Connect

    Park, S. K.; Chung, U. S.; Jung, K. J.; Park, J. H.

    2003-02-24

    Korea Research Reactor 1 (KRR-1), the first research reactor in Korea, has been operated since 1962, and the second one, Korea Research Reactor 2 (KRR-2) since 1972. The operation of both of them was phased out in 1995 due to their lifetime and operation of the new and more powerful research reactor, HANARO (High-flux Advanced Neutron Application Reactor; 30MW). Both are TRIGA Pool type reactors in which the cores are small self-contained units sitting in tanks filled with cooling water. The KRR-1 is a TRIGA Mark II, which could operate at a level of up to 250 kW. The second one, the KRR-2 is a TRIGA Mark III, which could operate at a level of up 2,000 kW. The decontamination and decommissioning (D & D) project of these two research reactors, the first D & D project in Korea, was started in January 1997 and will be completed to stage 3 by 2008. The aim of this decommissioning program is to decommission the KRR-1 & 2 reactors and to decontaminate the residual building structure s and the site to release them as unrestricted areas. KAERI (Korea Atomic Energy Research Institute) submitted the decommissioning plan and the environmental impact assessment reports to the Ministry of Science and Technology (MOST) for the license in December 1998, and was approved in November 2000.

  16. Genotypic and phenotypic characteristics of Methicillin-resistant Staphylococcus aureus (MRSA) strains, isolated on three different geography locations

    PubMed Central

    Ostojić, Maja; Hukić, Mirsada

    2015-01-01

    Staphylococcus aureus is a major cause of hospital-acquired infections worldwide. Increased frequency of methicillin-resistant Staphylococcus aureus (MRSA) in hospitalized patients and possibility of vancomycin resistance requires rapid and reliable characterization of isolates and control of MRSA spread in hospitals. Typing of isolates helps to understand the route of a hospital pathogen spread. The aim of this study was to investigate and compare genotypic and phenotypic characteristics of MRSA samples on three different geography locations. In addition, our aim was to evaluate three different methods of MRSA typing: spa-typing, agr-typing and GenoType MRSA. We included 104 samples of MRSA, isolated in 3 different geographical locations in clinical hospitals in Zagreb, Mostar, and Heidelberg, during the period of six months. Genotyping and phenotyping were done by spa-typing, agr-typing and dipstick assay GenoType MRSA. We failed to type all our samples by spa-typing. The most common spa-type in clinical hospital Zagreb was t041, in Mostar t001, and in Heidelberg t003. We analyzed 102/104 of our samples by agr-typing method. We did not find any agr-type IV in our locations. We analyzed all our samples by the dipstick assay GenoType MRSA. All isolates in our study were MRSA strains. In Zagreb there were no positive strains to PVL gene. In Mostar we have found 5/25 positive strains to PVL gene, in Heidelberg there was 1/49. PVL positive isolates were associated with spa-type t008 and agr-type I, thus, genetically, they were community-associated MRSA (CA-MRSA). Dipstick assay GenoType MRSA has demonstrated sufficient specificity, sensibility, simple performance and low cost, so we could introduce it to work in smaller laboratories. Using this method may expedite MRSA screening, thus preventing its spread in hospitals. PMID:26295294

  17. Lower ionosphere large positive and negative ions are still puzzling: A potential role in ion induced aerosol formation

    NASA Astrophysics Data System (ADS)

    Arnold, Frank

    2016-04-01

    Inspired by greatly improved possibilities in future rocket borne high mass resolution ion mass spectrometry, previous pioneering rocket borne ion-mass spectrometer measurements, made by our MPIK-Heidelberg research group in the lower ionosphere, are revisited and reanalyzed. Here the focus is placed upon puzzling observations of lower ionosphere large positive and large negative ions. These have a role in lower ionosphere free electron removal. They also have a potential role in lower ionosphere aerosol and eventually even cloud formation. Measurements and model simulations are presented.

  18. STORAGE RING MEASUREMENT OF ELECTRON IMPACT IONIZATION FOR Mg{sup 7+} FORMING Mg{sup 8+}

    SciTech Connect

    Hahn, M.; Lestinsky, M.; Novotny, O.; Savin, D. W.; Bernhardt, D.; Mueller, A.; Schippers, S.; Wolf, A.

    2010-04-01

    We report electron impact ionization cross section measurements for Mg{sup 7+} forming Mg{sup 8+} at center of mass energies from approximately 200 eV to 2000 eV. The experimental work was performed using the heavy-ion storage ring TSR located at the Max-Planck-Institut fuer Kernphysik in Heidelberg, Germany. We find good agreement with distorted wave calculations using both the GIPPER code of the Los Alamos Atomic Physics Code suite and using the Flexible Atomic Code.

  19. Semiautomatic detection and evaluation of autofluorescent areas in retinal images.

    PubMed

    Kolár, Radim; Jan, Jirí; Laemmer, Robert; Jirík, Radovan

    2007-01-01

    A semiautomatic approach to the detection and evaluation of the autofluorescent zones in retinal images, recognized as having a diagnostic value, has been designed based on fusing information from two Heidelberg Retina Angiograph imaging modalities - autofluorescent and infrared modes. The procedure, initiated by automatic preprocessing and region-of-interest determination continues by manually initiated segmentation via constrained region growing and ends with evaluating the size and geometrical coordinates of the AF regions with respect to the centre of the optic disc. Results are compared with those obtained by experienced ophthalmologists. PMID:18002708

  20. Modulation of retinal image vasculature analysis to extend utility and provide secondary value from optical coherence tomography imaging.

    PubMed

    Cameron, James R; Ballerini, Lucia; Langan, Clare; Warren, Claire; Denholm, Nicholas; Smart, Katie; MacGillivray, Thomas J

    2016-04-01

    Retinal image analysis is emerging as a key source of biomarkers of chronic systemic conditions affecting the cardiovascular system and brain. The rapid development and increasing diversity of commercial retinal imaging systems present a challenge to image analysis software providers. In addition, clinicians are looking to extract maximum value from the clinical imaging taking place. We describe how existing and well-established retinal vasculature segmentation and measurement software for fundus camera images has been modulated to analyze scanning laser ophthalmoscope retinal images generated by the dual-modality Heidelberg SPECTRALIS(®) instrument, which also features optical coherence tomography. PMID:27175375

  1. NOTE: Dosimetric characterization of a new miniature multileaf collimator

    NASA Astrophysics Data System (ADS)

    Hartmann, G. H.; Föhlisch, F.

    2002-06-01

    The dosimetrical characteristics of a new miniature multileaf collimator (ModuLeaf MLC, MRC Systems GmbH, Heidelberg, Germany) attached to the accessory holder of a Siemens accelerator with 6 MV x-rays (PRIMUS, Siemens OCS, Concord, California, USA) have been investigated. In particular, those parameters which are important for the accuracy of the treatment such as output factors, penumbra, field edge precision and transmission/leakage were determined. These data can now be used to implement specific dose calculation procedures for this miniature multileaf collimator in treatment planning systems.

  2. Precision measurement of sin2thetaW from semileptonic neutrino scattering

    NASA Astrophysics Data System (ADS)

    Abramowicz, H.; Belusevic, R.; Blondel, A.; Blümer, H.; Böckmann, P.; Brummel, H. D.; Buchholz, P.; Burkhardt, H.; Debu, P.; Duda, J.; Dydak, F.; Falkenburg, B.; Fiedler, M.; Geiges, R.; Geweniger, C.; Grant, A. L.; Guyot, C.; Hagelberg, R.; Hepp, V.; Hughes, E. W.; Kampschulte, B.; Keilwerth, H.; Kleinknecht, K.; Knobloch, J.; Krasny, M.; Królikowski, J.; Kurz, N.; Lipniacka, A.; Merlo, J.-P.; Müller, E.; Para, A.; Perez, P.; Perrier, F.; Pollman, D.; Ranjard, F.; Renk, B.; Schuller, J.-P.; Taureg, H.; Tittel, K.; Turlay, R.; Vallage, B.; Wachsmuth, H.; Wotschack, J.

    1986-07-01

    The ratio Rν of the neutral- to charged-current cross sections of neutrinos in iron has been measured in an exposure of the CERN-Dortmund-Heidelberg-Saclay neutrino detector to a 160-GeV/c neutrino narrow-band beam at the CERN Super Proton Synchrotron. The result is Rν=0.3072+/-0.0025(stat)+/- 0.0020(syst), for hadronic energy greater than 10 GeV. The electroweak mixing parameter is sin2thetaW=0.225+/-0.005(expt )+/-0.003(theor)+0.013(mc-1. 5 GeV/c2), where mc is the charm-quark mass.

  3. SUPERCONDUCTING NON-SCALING FFAG GANTRY FOR CARBON-PROTON CANCER THERAPY

    SciTech Connect

    TRBOJEVIC,D.; GUPTA, R.; PARKER, B.; KEIL, E.; SESSLER, A.M.

    2007-06-25

    We report on improvements in the non-scaling Fixed Field Alternating Gradient (FFAG) gantry design. As we previously reported, a major challenge of the carbodproton cancer therapy facilities is isocentric gantry design. The weight of the isocentric gantry transport elements in the latest Heidelberg carbon/proton facility is 135 tons. In this report we detail improvements to the previous non-scaling gantry design. We estimate that this non-scaling FFAG gantry would be almost hundred times lighter than traditional heavy ion gantries. Very strong focusing with small dispersion permits passage of different energies of carbon beams through the gantry's fixed magnetic field.

  4. [The Hygienist Karl Roelcke, M.D. (1907-1982). Annotations to the family biography].

    PubMed

    Mildenberger, Florian G

    2016-01-01

    Volker Roelcke, the well-known historian of medicine, wrote a biographical sketch on his father's role in National Socialism. Karl Roelcke (1907-1982) was an important hygienist at the University of Heidelberg and assistant to Ernst Rodenwaldt (1878-1965). Attempts to discuss the Nazi issue with his father directly ended unsuccessfully in the 1970s. In his essay of 2014, Volker Roelcke portrayed his father as quite sophisticated, but did not mention all aspects of his work. The present essay therefore offers new insights into the person of Karl Roelcke which are not constrained by family interests. PMID:27263217

  5. Efficient, Indirect Transverse Laser Cooling of a Fast Stored Ion Beam

    SciTech Connect

    Miesner, H.; Grimm, R.; Grieser, M.; Habs, D.; Schwalm, D.; Wanner, B.; Wolf, A.

    1996-07-01

    Three-dimensional laser cooling of a fast stored ion beam has been demonstrated at the Heidelberg Test Storage Ring. With a purely longitudinal cooling force applied to a 7.3 MeV {sup 3}Be{sup +} beam, we have observed an efficient transverse cooling effect. We interpret this observation as being due to a thermal intrabeam relaxation between the different degrees of freedom that is caused by Coulomb collisions of the stored particles. {copyright} {ital 1996 The American Physical Society.}

  6. Observables sensitive to absolute neutrino masses. II

    SciTech Connect

    Fogli, G. L.; Marrone, A.; Rotunno, A. M.; Lisi, E.; Melchiorri, A.; Palazzo, A.; Silk, J.; Slosar, A.

    2008-08-01

    In this followup to Phys. Rev. D 75, 053001 (2007) , we report updated constraints on neutrino mass-mixing parameters, in light of recent neutrino oscillation data (KamLAND, SNO, and MINOS) and cosmological observations (WMAP 5-year and other data). We discuss their interplay with the final 0{nu}2{beta} decay results in {sup 76}Ge claimed by part of the Heidelberg-Moscow Collaboration, using recent evaluations of the corresponding nuclear matrix elements, and their uncertainties. We also comment on the 0{nu}2{beta} limits in {sup 130}Te recently set by Cuoricino and on prospective limits or signals from the Karlsruhe tritium neutrino experiment.

  7. Few-Photon Multiple Ionization of Ne and Ar by Strong Free-Electron-Laser Pulses

    SciTech Connect

    Moshammer, R.; Jiang, Y. H.; Rudenko, A.; Ergler, Th.; Schroeter, C. D.; Luedemann, S.; Zrost, K.; Dorn, A.; Ferger, T.; Kuehnel, K. U.; Ullrich, J.; Foucar, L.; Titze, J.; Jahnke, T.; Schoeffler, M.; Doerner, R.; Fischer, D.; Weber, T.; Zouros, T. J. M.; Duesterer, S.

    2007-05-18

    Few-photon multiple ionization of Ne and Ar atoms by strong vacuum ultraviolet laser pulses from the free-electron laser at Hamburg was investigated differentially with the Heidelberg reaction microscope. The light-intensity dependence of Ne{sup 2+} production reveals the dominance of nonsequential two-photon double ionization at intensities of I<6x10{sup 12} W/cm{sup 2} and significant contributions of three-photon ionization as I increases. Ne{sup 2+} recoil-ion-momentum distributions suggest that two electrons absorbing ''instantaneously'' two photons are ejected most likely into opposite hemispheres with similar energies.

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

  9. Can Automated Imaging for Optic Disc and Retinal Nerve Fiber Layer Analysis Aid Glaucoma Detection?

    PubMed Central

    Banister, Katie; Boachie, Charles; Bourne, Rupert; Cook, Jonathan; Burr, Jennifer M.; Ramsay, Craig; Garway-Heath, David; Gray, Joanne; McMeekin, Peter; Hernández, Rodolfo; Azuara-Blanco, Augusto

    2016-01-01

    Purpose To compare the diagnostic performance of automated imaging for glaucoma. Design Prospective, direct comparison study. Participants Adults with suspected glaucoma or ocular hypertension referred to hospital eye services in the United Kingdom. Methods We evaluated 4 automated imaging test algorithms: the Heidelberg Retinal Tomography (HRT; Heidelberg Engineering, Heidelberg, Germany) glaucoma probability score (GPS), the HRT Moorfields regression analysis (MRA), scanning laser polarimetry (GDx enhanced corneal compensation; Glaucoma Diagnostics (GDx), Carl Zeiss Meditec, Dublin, CA) nerve fiber indicator (NFI), and Spectralis optical coherence tomography (OCT; Heidelberg Engineering) retinal nerve fiber layer (RNFL) classification. We defined abnormal tests as an automated classification of outside normal limits for HRT and OCT or NFI ≥ 56 (GDx). We conducted a sensitivity analysis, using borderline abnormal image classifications. The reference standard was clinical diagnosis by a masked glaucoma expert including standardized clinical assessment and automated perimetry. We analyzed 1 eye per patient (the one with more advanced disease). We also evaluated the performance according to severity and using a combination of 2 technologies. Main Outcome Measures Sensitivity and specificity, likelihood ratios, diagnostic, odds ratio, and proportion of indeterminate tests. Results We recruited 955 participants, and 943 were included in the analysis. The average age was 60.5 years (standard deviation, 13.8 years); 51.1% were women. Glaucoma was diagnosed in at least 1 eye in 16.8%; 32% of participants had no glaucoma-related findings. The HRT MRA had the highest sensitivity (87.0%; 95% confidence interval [CI], 80.2%–92.1%), but lowest specificity (63.9%; 95% CI, 60.2%–67.4%); GDx had the lowest sensitivity (35.1%; 95% CI, 27.0%–43.8%), but the highest specificity (97.2%; 95% CI, 95.6%–98.3%). The HRT GPS sensitivity was 81.5% (95% CI, 73.9%–87.6%), and

  10. Electron beam ion source and electron beam ion trap (invited)

    SciTech Connect

    Becker, Reinard; Kester, Oliver

    2010-02-15

    The electron beam ion source (EBIS) and its trap variant [electron beam ion trap (EBIT)] celebrated their 40th and 20th anniversary, respectively, at the EBIS/T Symposium 2007 in Heidelberg. These technologically challenging sources of highly charged ions have seen a broad development in many countries over the last decades. In contrast to most other ion sources the recipe of improvement was not ''sorcery'' but a clear understanding of the physical laws and obeying the technological constraints. This review will report important achievements of the past as well as promising developments in the future.

  11. BESO: first light at the high-resolution spectrograph for the Hexapod-Telescope

    NASA Astrophysics Data System (ADS)

    Steiner, Ingo; Stahl, Otmar; Seifert, Walter; Chini, Rolf; Quirrenbach, Andreas

    2008-07-01

    BESO (Bochum Echelle Spectrograph for OCA)is a high-resolution echelle spectrograph which has been built by Ruhr-Universitaet, Bochum and Landessternwarte Heidelberg. It is fiber-coupled to the 1.5m Hexapod-Telescope at the Observatario Cerro Armazones (OCA), Chile. The first light spectra show that the resolution of 48.000 over a spectral range from 370 nm to 840 nm has been achieved. An alignment by design approach has been followed to assemble the fiber-head optics at the telescope side of fiber coupled instrument.

  12. Constraints on the Interstellar Dust Flux Based on Stardust at Home Search Results

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael E.; Westphal, J.; Allen, C.; Anderson, D.; Bajt, S.; Bechtel, H. A.; Borg, J.; Brenker, F.; Bridges, J.; Brownlee, D. E.; Burchell, M.

    2011-01-01

    Recent advances in active particle selection in the Heidelberg Van de r Graaf (VdG) dust accelerator have led to high-fidelity, low-backgro und calibrations of track sizes in aerogel as a function of particle size and velocity in the difficult regime above 10 km sec..1 and sub micron sizes. To the extent that the VdG shots are analogs for inters tellar dust (ISD) impacts, these new measurements enable us to place preliminary constraints on the ISD flux based on Stardust@home data.

  13. Interpretation of the TRADE In-Pile source multiplication experiments

    NASA Astrophysics Data System (ADS)

    Mercatali, Luigi; Carta, Mario; Peluso, Vincenzo

    2006-06-01

    Within the framework of the neutronic characterization of the TRIGA RC-1 reactor in support to the TRADE (TRiga Accelerator Driven Experiment) program, the interpretation of the subcriticality level measurements performed in static regime during the TRADE In-Pile experimental program is presented. Different levels of subcriticality have been measured using the MSA (Modified Source Approximated) method by the insertion of a standard fixed radioactive source into different core positions. Starting from a reference configuration, fuel elements were removed: control rods were moved outward as required for the coupling experiments envisioned with the proton accelerator and fission chambers were inserted in order to measure subcritical count rates. A neutron-physics analysis based on the modified formulation of the source multiplication method (MSM) has been carried out, which requires the systematic solution for each experimental configuration of the homogeneous, both in the forward and adjoint forms, and inhomogeneous Boltzmann equations. By means of such a methodology calculated correction factors to be applied to the MSA measured reactivities were produced in order to take into account spatial and energetic effects creating changes in the detector efficiencies and effective source with respect to the calibration configuration. The methodology presented has been tested against a large number of experimental states. The measurements have underlined the sensitivity of the MSA measured reactivities to core geometry changes and control rod perturbations; the efficiency of MSM factors to dramatically correct for this sensitivity is underlined, making of this technique a relevant methodology in view of the incoming US RACE program to be performed in TRIGA reactors.

  14. Nuclear-driven flashlamp pumping of the atomic iodine laser. Final report

    SciTech Connect

    Miley, G.H.

    1992-03-01

    This report is a study of the atomic iodine laser pumped with nuclear- excited XeBr fluorescence. Preliminary experiments, conducted in the TRIGA reactor investigated the fluorescence of the excimer XeBr under nuclear pumping with {sup 10}B and {sup 3}He, for use as a flashlamp gas to stimulate the laser. These measurements included a determination of the fluorescence efficiency (light emitted in the wavelength region of interest, divided by energy deposited in the gas) of XeBr under nuclear pumping, with varying excimer mixtures. Maximum fluorescence efficiencies were approximately 1%. In order to better understand XeBr under nuclear excitation, a kinetics model of the system was prepared. The model generated the time-dependant concentrations of 20 reaction species for three pulse sizes, a TRIGA pulse, a fast burst reactor pulse, and an e-beam pulse. The modeling results predicted fluorescence efficiencies significantly higher (peak efficiencies of approximately 10%) than recorded in the fluorescence experiments. The cause of this discrepancy was not fully determined. A ray tracing computer model was also prepared to evaluate the efficiency with which nuclear-induced fluorescence generated in one cavity of a laser could be coupled into another cavity containing an iodine lasant. Finally, an experimental laser cell was constructed to verify that nuclear-induced XeBr fluorescence could be used to stimulate a laser. Lasing was achieved at 1.31 micron in the TRIGA using C{sub 3}F{sub 7}I, a common iodine lasant. Peak laser powers were approximately 20 mW. Measured flashlamp pump powers at threshold agreed well with literature values, as did lasant pressure dependency on laser operation.

  15. Nuclear-driven flashlamp pumping of the atomic iodine laser

    SciTech Connect

    Miley, G.H.

    1992-03-01

    This report is a study of the atomic iodine laser pumped with nuclear- excited XeBr fluorescence. Preliminary experiments, conducted in the TRIGA reactor investigated the fluorescence of the excimer XeBr under nuclear pumping with {sup 10}B and {sup 3}He, for use as a flashlamp gas to stimulate the laser. These measurements included a determination of the fluorescence efficiency (light emitted in the wavelength region of interest, divided by energy deposited in the gas) of XeBr under nuclear pumping, with varying excimer mixtures. Maximum fluorescence efficiencies were approximately 1%. In order to better understand XeBr under nuclear excitation, a kinetics model of the system was prepared. The model generated the time-dependant concentrations of 20 reaction species for three pulse sizes, a TRIGA pulse, a fast burst reactor pulse, and an e-beam pulse. The modeling results predicted fluorescence efficiencies significantly higher (peak efficiencies of approximately 10%) than recorded in the fluorescence experiments. The cause of this discrepancy was not fully determined. A ray tracing computer model was also prepared to evaluate the efficiency with which nuclear-induced fluorescence generated in one cavity of a laser could be coupled into another cavity containing an iodine lasant. Finally, an experimental laser cell was constructed to verify that nuclear-induced XeBr fluorescence could be used to stimulate a laser. Lasing was achieved at 1.31 micron in the TRIGA using C{sub 3}F{sub 7}I, a common iodine lasant. Peak laser powers were approximately 20 mW. Measured flashlamp pump powers at threshold agreed well with literature values, as did lasant pressure dependency on laser operation.

  16. Hybrid Reactor Simulation of Boiling Water Reactor Power Oscillations

    SciTech Connect

    Huang Zhengyu; Edwards, Robert M.

    2003-08-15

    Hybrid reactor simulation (HRS) of boiling water reactor (BWR) instabilities, including in-phase and out-of-phase (OOP) oscillations, has been implemented on The Pennsylvania State University TRIGA reactor. The TRIGA reactor's power response is used to simulate reactor neutron dynamics for in-phase oscillation or the fundamental mode of the reactor modal kinetics for OOP oscillations. The reactor power signal drives a real-time boiling channel simulation, and the calculated reactivity feedback is in turn fed into the TRIGA reactor via an experimental changeable reactivity device. The thermal-hydraulic dynamics, together with first harmonic mode power dynamics, is digitally simulated in the real-time environment. The real-time digital simulation of boiling channel thermal hydraulics is performed by solving constitutive equations for different regions in the channel and is realized by a high-performance personal computer. The nonlinearity of the thermal-hydraulic model ensures the capability to simulate the oscillation phenomena, limit cycle and OOP oscillation, in BWR nuclear power plants. By adjusting reactivity feedback gains for both modes, various oscillation combinations can be realized in the experiment. The dynamics of axially lumped power distribution over the core is displayed in three-dimensional graphs. The HRS reactor power response mimics the BWR core-wide power stability phenomena. In the OOP oscillation HRS, the combination of reactor response and the simulated first harmonic power using shaping functions mimics BWR regional power oscillations. With this HRS testbed, a monitoring and/or control system designed for BWR power oscillations can be experimentally tested and verified.

  17. Status of highly loaded uranium-zirconium hydride Low Enriched Uranium (LEU) fuel programs

    SciTech Connect

    West, G.B.

    1984-07-01

    The LEU uranium-zirconium hydride fuel has successfully completed all essential development testing and is offered commercially in both the 20 weight percent and 45 weight percent uranium concentrations for existing TRIGA reactors and as a conversion fuel for plate-type reactors. Several reactor facilities have already begun conversion to LEU uranium-zirconium hydride fuel. Currently, U-ZrH LEU fuel is in use in a mixed plate and rod fuel configuration in the 1.0 MW reactor at the National Tsing Hua University in Taipei, Taiwan. A complete core of 20 wt-$ LEU fuel has been fabricated for the 3 MW forced flow TRIGA Mark II reactor system with pulsing capability scheduled to be completed in 1984 in Bangladesh. Also, a complete core of 20 vt-% 4-rod shrouded cluster fuel has been fabricated and shipped for conversion and upgrading of the PRR-1 reactor in the Philippines. The converted reactor will operate at 3 MW with forced cooling and have pulsing capability. Startup is now scheduled for early 1985. U-ZrH LEU fuel has also been delivered to existing TRIGA reactor facilities in Malaysia, Thailand and Yugoslavia and is being put to use as new fuel is needed to meet burnup requirements. For stepwise conversions of higher power reactors (>5 MW), where flow distribution and neutron spectrum effects are of greater importance, a detailed analysis and study is a prerequisite. A joint program involving GA, ANL, and the Cekmece Center is now in progress for analysis of a single U-ZrH LEU fuel test cluster operating in the 5 MW HEU plate-type core of the TR-2 reactor at the Cekmece Nuclear Research and Training Center in Istanbul, Turkey. Inserting this one cluster would be the initial step in a stepwise conversion of the HEU plate-type core to U-ZrH LEU fuel.

  18. Trace elements in the human scalp hair and finger nails as affected by infection with Schistosoma mansoni

    NASA Astrophysics Data System (ADS)

    El-Khatib, Ahmed M.; Bahnassy, Ahmed A.; Denton, M.

    1995-01-01

    The concentration of 13 elements has been determined in finger nail and scalp hair of 4 groups representing normal and infected Schistosoma mansoni subjects. Samples were irradiated by thermal neutrons from a Triga Mark III Reactor, for 10 min. Measurements were made using a HPGe detector coupled with ADC and PDP {11}/{34} data processing equipment. The results showed significant increases of Al, Cl, I and Br in both finger nails and scalp hair of bilharzial patients above those of normal subjects while Mg, Ca, V, Mn, Cu, Sr, K, S and Na showed significant decreases. Most of the elements showed a higher concentration in finger nails than in hair.

  19. ANL/WSU radiation damage studies

    SciTech Connect

    Jankowski, D.; Lopiano, D.; Proudfoot, J.; Underwood, D.; Miles, L.; Neidiger, J.; Tripard, G.

    1993-12-31

    We report preliminary results for the radiation hardness of (polystryrene) plastic scintillator stacks using a spectrum of energy hardened neutrons from a MARK-III TRIGA reactor. The total dose ranged from 100 KRad to 3MRad. The corresponding fluence was 3.8 {times} 10{sup 13} to 3.8 {times} 10{sup 14} (n/cm/cm) with the gamma contribution on the order 2--3% (of fluence). The measurements used Li-6, Li-7 Thermo-luminescence dosimeters. Radiochromic/GaF- Chromic film, and activated foils simultaneously allowing an inter-comparison of these various methods of dosimetry.

  20. Density of radiolytic gas bubbles in polymethyl methacrylate

    NASA Astrophysics Data System (ADS)

    Makkonen, T.; Tiainen, O. J. A.; Valkiainen, M.; Winberg, M.

    The density of the radiolytic gas bubbles in irradiated polymethyl methacrylate was measured during subsequent heat treatment as a function of radiation dose. The samples were irradiated in the core of the Triga Mark II reactor in Otaniemi. After the irradiation periods the samples were heat treated at 393 K. The number of the bubbles could be explained by a thermal activation model. The bubbles are born in material inhomogeneities and the threshold dose for the bubble initiation was about 25 Mrad for the heat treatment at 393 K under the atmospheric pressure.

  1. Investigation of Radiation Affected High Temperature Superconductors - YBCO

    NASA Astrophysics Data System (ADS)

    Veterníková, J.; Chudý, M.; Slugeň, V.; Sojak, S.; Degmová, J.; Snopek, J.

    In this paper, high temperature superconductors are studied in terms of radiation stability, which is necessary for application in fusion reactors. Perspective superconducting materials based on YBCO (Perkovskite structure) were measured by positron annihilation lifetime spectroscopy. Measurements were performed for samples prior to and after fast neutron irradiation in TRIGA MARK II reactor in Vienna. The samples demonstrated accumulation of Cu-O di-vacancies due to the irradiation. Nevertheless, the structure showed regeneration during thermal treatment by defects recombination. Positron spectroscopy results were complemented with values of critical temperature, which also showed changes of superconducting properties after the irradiation and the annealing.

  2. Investigations on fiberoptic behaviour during gamma irradiation

    NASA Astrophysics Data System (ADS)

    Siehs, J.

    1980-12-01

    The behavior of bulk glasses and fiber optics under gamma irradiation and two types of annealing processes (thermal and optical) were investigated. The samples were irradiated in the thermal column of the TRIGA Mark II reactor. The irradiation induced losses of transmission were measured in a dual beam spectrophotometer. The transmission was measured one hour after reactor shut-down. Thermal annealing was done at 300, 400 and 500 C. Photo bleaching was investigated with a quartz-lamp, an arc-lamp and an UV-laser light.

  3. Studies of the behavior of a reactor neutron beam at the sample position of a diffractometer using silicon monochromators

    NASA Astrophysics Data System (ADS)

    Ahmed, F. U.; Ahsan, M. H.; Khan, Aysha A.; Kamal, I.; Awal, M. A.; Ahmad, A. A. Z.

    1992-02-01

    A computer program TISTA has been developed for calculation of different aspects of designing a double axis neutron spectrometer at the TRIGA Mark II research reactor of the Atomic Energy Research Establishment, Dhaka, Bangladesh. The mathematical algorithms used in this program are based on the formalisms used by Fischer, Sabine and Bacon. Angle and energy resolutions and flux density as functions of neutron wave length, beam collimation, crystal asymmetry and deviation from zero-Bragg-angle position for different silicon crystal planes (111, 220, 311) have been calculated.

  4. Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor

    NASA Astrophysics Data System (ADS)

    Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.

    2008-03-01

    This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.

  5. Search for free neutron-antineutron oscillations

    NASA Astrophysics Data System (ADS)

    Bressi, G.; Calligarich, E.; Cambiaghi, M.; Dolfini, R.; Genoni, M.; Berzolari, A. Gigli; Lanza, A.; Liguori, G.; Mauri, F.; Piazzoli, A.; Ratti, S. P.; Torre, P.; Bini, C.; Conversi, M.; de Zorzi, G.; Gauzzi, P.; Massa, F.; Zanello, D.; Cardarelli, R.; Santonico, R.; Scannicchio, D.; Terrani, M.

    1989-06-01

    A search for free neutron-antineutron oscillations has been carried out at the Pavia Triga Mark II research reactor. A thin carbon target is crossed by a beam of thermal neutrons propagating in a 18.5 m long channel where the earth magnetic field is attenuated by a factor of 50. The total neutron current through the target is 3.2×1010 n/s. Possible antineutron annihilations are identified by a large track detector surrounding the target. A lower limit on the oscillation time of 4.7×105 s (90% C.L.) has been reached.

  6. A history of basic neutron radiography research at Rikkyo University

    NASA Astrophysics Data System (ADS)

    Kobayashi, H.

    2011-09-01

    A study of neutron imaging was initiated by a research group in our institute using the 100 kW Rikkyo TRIGA reactor, in 1984. A series of studies at the Rikkyo University was reported in the proceedings of these conferences and others and were covered mainly in the field of neutron beam qualification methods, analysis of image qualification, new imaging methods, and analysis of neutron behavior in materials. In this paper, a history of these principal studies will be summarized and a few unresolved basic studies will also be mentioned.

  7. Dihydrogen gas emission of a 250kW(th) research reactor.

    PubMed

    Steinhauser, Georg; Villa, Mario

    2011-11-01

    The Vienna TRIGA pool-type reactor emits tiny gas bubbles at 250kW. They add up to a total volume of ∼2.4L in 7h of daily operation. The bubbles consist of nitrogen (72.5vol%), hydrogen (17.2%), oxygen plus argon (12.0%) and carbon dioxide (0.23%). The emission of constituents of air is caused by degassing of dissolved air in the hot regions of the reactor. Hydrogen results from neutron-induced radiolysis of the cooling water. This emission should be kept in mind for reasons of fire protection even for low-power reactors. PMID:21601464

  8. Design and testing of a 10B4C capsule for spectral-tailoring in mixed-spectrum reactors

    NASA Astrophysics Data System (ADS)

    Greenwood, L. R.; Wittman, R.; Metz, L. A.; Finn, E. C.; Friese, J. I.

    2014-04-01

    A boron carbide capsule highly enriched in 10B has been designed and used for spectral-tailoring experiments at the TRIGA reactor at Washington State University. New experiments show that enriching the boron to 96% B-10 results in additional absorption of neutrons in the resonance region thereby producing a neutron spectrum that is much closer to a pure 235U fission spectrum than measured previously with a natural boron carbide capsule. A cadmium outer cover was used to reduce thermal alpha heating. The neutron spectrum calculated with MCNP was found to be in very good agreement with measured activation rates from neutron fluence monitors.

  9. NSDUAZ unfolding package for neutron spectrometry and dosimetry with Bonner spheres.

    PubMed

    Vega-Carrillo, H R; Ortiz-Rodríguez, J M; Martínez-Blanco, M R

    2012-12-01

    NSDUAZ (Neutron Spectrometry and Dosimetry from the Universidad Autónoma de Zacatecas) is a user friendly neutron unfolding package for Bonner sphere spectrometer with (6)LiI(Eu) developed under LabView(®) environment. Unfolding is carried out using a recursive iterative procedure with the SPUNIT algorithm, where the starting spectrum is obtained from a library initial guess spectra to start the iterations. The NSDUAZ performance was evaluated using (252)Cf, (252)Cf/D(2)O, (241)AmBe neutron sources and the neutrons outside the radial beam port of a TRIGA Mark III nuclear reactor running to 10 W. PMID:22578610

  10. New material for low-dose brachytherapy seeds: Xe-doped amorphous carbon films with post-growth neutron activated 125I.

    PubMed

    Gonçalves, R G F; Pinheiro, M V B; Lacerda, R G; Ferlauto, A S; Ladeira, L O; Krambrock, K; Leal, A S; Viana, G A; Marques, F C

    2011-01-01

    We report a novel material for use in (125)I brachytherapy that consists of amorphous carbon films grown by ion-beam-assisted deposition and doped with Xe (5 at%) by implantation. Samples of these films grown on Si substrates were irradiated with neutrons in a TRIGA-I nuclear reactor for the production (125)Xe, and latter characterized by gamma spectroscopy. The results indicate that the (124)Xe was efficiently converted into (125)Xe, the precursor of (125)I, and support the activity calculations for a model brachytherapy seed. PMID:20729094

  11. Cubic boron nitride: A new prospective material for ultracold neutron application

    NASA Astrophysics Data System (ADS)

    Sobolev, Yu.; Lauer, Th.; Borisov, Yu.; Daum, M.; du Fresne, N.; Göltl, L.; Hampel, G.; Heil, W.; Knecht, A.; Keunecke, M.; Kratz, J. V.; Lang, T.; Meister, M.; Plonka-Spehr, Ch.; Pokotilovski, Yu.; Reichert, P.; Schmidt, U.; Krist, Th.; Wiehl, N.; Zenner, J.

    2010-03-01

    At the ultracold neutron (UCN) source of the TRIGA research reactor in Mainz, we have measured for the first time the material optical wall-potential of cubic boron nitride. The measurements were performed with a time-of-flight (TOF) spectrometer. The samples investigated had a wall-potential of (305±15) neV. This value is in good agreement with the result extracted from neutron reflectometry data and theoretical expectations. Because of its high critical velocity for UCN and its good dielectric characteristics, cubic boron nitride coatings (isotopically enriched) will be useful for a number of applications in UCN experiments.

  12. A TCT and annealing study on Magnetic Czochralski silicon detectors irradiated with neutrons and 24 GeV/ c protons

    NASA Astrophysics Data System (ADS)

    Pacifico, Nicola; Creanza, Donato; de Palma, Mauro; Manna, Norman; Kramberger, Gregor; Moll, Michael

    2010-01-01

    Silicon diodes (pad detectors) were irradiated with 24 GeV/ c protons at the CERN PS IRRAD1 facility and with neutrons at the TRIGA reactor in Ljubljana (Slovenia). The diodes were realized on Magnetic Czochralski (MCz) grown silicon, of both n- and p-type. After irradiation, an annealing study with CV measurements was performed on 24 GeV/ c proton irradiated detectors, looking for hints of type inversion after irradiation and during annealing. Other pad detectors were studied using the TCT (transient current technique), to gather information about the field profile in the detector bulk and thus about the effective space charge distribution within it.

  13. Flux and instrumentation upgrade for the epithermal neutron beam facility at Washington State University.

    PubMed

    Nigg, D W; Venhuizen, J R; Wemple, C A; Tripard, G E; Sharp, S; Fox, K

    2004-11-01

    An epithermal neutron beam facility for preclinical neutron capture therapy research has been constructed at the Washington State University TRIGA research reactor installation. Subsequent to a recent upgrade, this new facility offers a high-purity epithermal beam with intensity on the order of 1.2x10(9)n/cm(2)s. Key features include a fluoride-based design for the neutron filtering and moderating components as well as a novel collimator design that allows ease of assembly and disassembly of the beamline components. PMID:15308181

  14. Thermionic fuel element Verification Program - Overview

    NASA Astrophysics Data System (ADS)

    Bohl, Richard J.; Dahlberg, Richard C.; Dutt, Dale S.; Wood, John T.

    The TFE Verification Program is in the sixth year of a program to demonstrate the performance and lifetime of thermionic fuel elements for high power space applications. Data from accelerated tests in FETF and EBR-II show component lifetimes longer than 7 yr. Alumina insulators have shown good performance at high fast fluence. Graphite-cesium reservoirs based on isotropic graphite also meet requirements. Three TFEs are currently operating in the TRIGA reactor, the oldest having accumulated 15,000 hr of irradiation as of 1 October 1990.

  15. Flux and Instrumentation Upgrade for the Epithermal Neutron Beam Facility at Washington State University

    SciTech Connect

    David W. Nigg; J.R. Venhuizen; C.E. Wemple; G. E. Tripard; S. Sharp; K. Fox

    2004-11-01

    An epithermal neutron beam facility for preclinical neutron capture therapy research has been constructed at the Washington State University TRIGA research reactor installation. Subsequent to a recent upgrade, this new facility offers a high-purity epithermal beam with intensity on the order of 1.2×109 n/cm2 s. Key features include a fluoride-based design for the neutron filtering and moderating components as well as a novel collimator design that allows ease of assembly and disassembly of the beamline components.

  16. Reconfiguration of the NRAD delay loop for proposed 1 MW operations

    SciTech Connect

    Heidel, C.C.; Richards, W.J.; Pruett, D.P.

    1984-01-01

    The Hot Fuel Examination Facility, HFEF, is one of several facilities located at the Argonne Site. HFEF comprises a large hot cell where both nondestructive and destructive examination of highly-irradiated reactor fuels are conducted in support of the LMFBR program. One of the nondestructive examination technqiues utilized at HFEF is neutron radiography. Neutron radiography is provided by the NRAD reactor facility, which is located beneath the HFEF hot cell. The NRAD reactor is a TRIGA reactor and is operated at a steady-state power level of 250 kw solely for neutron radiography and the development of radiography techniques. Modifications of the NRAD delay loop for 1 MW operations are described.

  17. Hot Fuel Examination Facility's neutron radiography reactor

    SciTech Connect

    Pruett, D.P.; Richards, W.J.; Heidel, C.C.

    1983-01-01

    Argonne National Laboratory-West is located near Idaho Falls, Idaho, and is operated by the University of Chicago for the United States Department of Energy in support of the Liquid Metal Fast Breeder Reactor Program, LMFBR. The Hot Fuel Examination Facility, HFEF, is one of several facilities located at the Argonne Site. HFEF comprises a large hot cell where both nondestructive and destructive examination of highly-irradiated reactor fuels are conducted in support of the LMFBR program. One of the nondestructive examination techniques utilized at HFEF is neutron radiography, which is provided by the NRAD reactor facility (a TRIGA type reactor) below the HFEF hot cell.

  18. Present status of the medical irradiation facility at the Musashi reactor

    SciTech Connect

    Matsumoto, T.; Aizawa, O.; Nozaki, T.; Sato, T. )

    1989-07-01

    Boron neutron capture therapy (BNCT) of malignant brain tumors has been efficiently performed since March 1977, and the first human case of malignant melanoma was also successfully treated on July 1987 in our reactor (Musashi reactor, TRIGA-II, 100 kW). To obtain both good irradiation field characteristics and a better irradiation facility, some tests and developments have been continued in accordance with the study of medical and biological irradiations. The results of these evaluations and a new approach are presented.6 references.

  19. Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor

    SciTech Connect

    Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.

    2008-03-17

    This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.

  20. Design and Testing of a Boron Carbide Capsule for Spectral Tailoring in Mixed-Spectrum Reactors

    SciTech Connect

    Greenwood, Lawrence R.; Wittman, Richard S.; Pierson, Bruce D.; Metz, Lori A.; Payne, Rosara F.; Finn, Erin C.; Friese, Judah I.

    2012-03-01

    A boron carbide capsule has been designed and used for spectral-tailoring experiments at the TRIGA reactor at Washington State University. Irradiations were conducted in pulsed mode and in continuous operation for up to 4 hours. A cadmium cover was used to reduce thermal heating. The neutron spectrum calculated with MCNP was found to be in good agreement with reactor dosimetry measurements using the STAY'SL computer code. The neutron spectrum resembles that of a fast reactor. Design of a capsule using boron carbide enriched in {sup 10}B shows that it is possible to produce a neutron spectrum similar to {sup 235}U fission.

  1. INAA and DNAA for uranium determination in geological samples from Egypt.

    PubMed

    El-Taher, A

    2010-06-01

    Uranium isotopes found in soil, rock, water, plants, air, etc., contribute to the natural radiation exposure of the population. U concentrations in some Egyptian environmental samples like Toshki soil, Aswan iron-ore, and phosphate samples from El-Sibayia in the Nile Valley and El-Quseir in the Red Sea coast were determined using instrumental neutron activation analysis (INAA) and delayed neutron activation analysis (DNAA) in the Mainz TRIGA research reactor. The results showed that the phosphate rocks are rich natural sources of uranium among the other minerals forming the earth crust. PMID:20185320

  2. Thermionic fuel element verification program—overview

    NASA Astrophysics Data System (ADS)

    Bohl, Richard J.; Dutt, Dale S.; Dahlberg, Richard C.; Wood, John T.

    1991-01-01

    TFE Verification Program is in the sixth year of a program to demonstrate the performance and lifetime of thermionic fuel elements for high power space applications. It is jointly funded by SIDO and DOE. Data from accelerated tests in FFTF and EBR-II show component lifetimes longer than 7 years. Alumina insulators have shown good performance at high fast fluence. Graphite-cesium reservoirs based on isotropic graphite also meet requirements. Three TFEs are current operating in the TRIGA reactor, the oldest having accumulated 15,000 hours of irradiation as of 1 October 1990.

  3. Design and Testing of a 10B4C Capsule for Spectral-Tailoring in Mixed-Spectrum Reactors

    SciTech Connect

    Greenwood, Lawrence R.; Wittman, Richard S.; Metz, Lori A.; Finn, Erin C.; Friese, Judah I.

    2014-04-11

    A boron carbide capsule highly enriched in 10B has been designed and used for spectral-tailoring experiments at the TRIGA reactor at Washington State University. New experiments show that enriching the boron to 96% B-10 results in additional absorption of neutrons in the resonance region thereby producing a neutron spectrum that is much closer to a pure 235U fission spectrum. A cadmium outer cover was used to reduce thermal heating. The neutron spectrum calculated with MCNP was found to be in very good agreement with measured activation rates from neutron fluence monitors.

  4. Choroidal thickness changes with photodynamic therapy for a diffuse choroidal hemangioma in Sturge–Weber syndrome.

    PubMed

    Cacciamani, Andrea; Scarinci, Fabio; Parravano, Mariacristina; Giorno, Paola; Varano, Monica

    2014-10-01

    The aim of this study was to evaluate the choroidal thickness (CT) changes associated with visual function following photodynamic therapy (PDT) for a diffuse choroidal hemangioma in Sturge–Weber syndrome. We report a case of Sturge–Weber syndrome and symptomatic serous retinal detachment (SRD) with diffuse choroidal hemangioma treated with PDT. Visual acuity (VA), macular sensitivity measured by means of MP1 microperimeter (Nidek Technologies, Padova, Italy), retinal and CT, measured by means of enhanced depth optical coherence tomography (EDI–OCT, Spectralis, Heidelberg Engineering, Heidelberg, Germany) were analyzed at baseline, 3 and 12 months follow-up.After the PDT VA and macular sensitivity improved.The OCT examination showed the resolution of SRD. The choroid was measured after PDT using EDI–OCT. At baseline, the subfoveal CT showed a progressive thickness reduction from 251 to 83 lm during follow-up. To our knowledge, this is the first report of CT changes after PDT for a diffuse choroidal hemangioma in Sturge–Weber syndrome in a longterm follow-up. The CT measurement represents a potential parameter to better follow choroidal hemangiomas and their response to treatment. However,the long-term choroidal changes should be carefully taken into account. PMID:24658736

  5. Correlation between Visual Acuity, Inner Segment/Outer Segment Junction, and Cone Outer Segment Tips Line Integrity in Uveitic Macular Edema

    PubMed Central

    Tortorella, Paolo; D'Ambrosio, Enzo; Iannetti, Ludovico; De Marco, Federica; La Cava, Maurizio

    2015-01-01

    Purpose. To investigate the correlation between best-corrected visual acuity (BCVA), the foveal inner segment/outer segment (IS/OS) junction or ellipsoid portion of inner segment (EPIS/ellipsoid zone), and the cone outer segment tips (COST) line or interdigitation zone integrity in eyes with uveitic macular edema (ME). Method. A retrospective observational study involving all patients from January 2012 to December 2013 with uveitic ME was performed. All patients underwent BCVA using Snellen charts spectral-domain optical coherence tomography (SD-OCT) examination using Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany). Results. Fifty-two eyes from 45 patients were included in this study. Multivariate analysis showed a negative correlation between BCVA and the central retinal subfield thickness (CST), the cystoid pattern of edema, and the interdigitation zone interruption. Univariate logistic analysis showed a strong correlation between the ellipsoid zone and the interdigitation zone integrity. Conclusions. The ellipsoid zone defect, the interdigitation zone interruption, and the CST are correlated with poor vision. Visual acuity is also strongly affected by the cystoid pattern. The interdigitation zone integrity appears to be the most important factor in the visual prognosis of uveitic ME. PMID:26167505

  6. Development of a two-parameter slit-scan flow cytometer for screening of normal and aberrant chromosomes: application to a karyotype of Sus scrofa domestica (pig)

    NASA Astrophysics Data System (ADS)

    Hausmann, Michael; Doelle, Juergen; Arnold, Armin; Stepanow, Boris; Wickert, Burkhard; Boscher, Jeannine; Popescu, Paul C.; Cremer, Christoph

    1992-07-01

    Laser fluorescence activated slit-scan flow cytometry offers an approach to a fast, quantitative characterization of chromosomes due to morphological features. It can be applied for screening of chromosomal abnormalities. We give a preliminary report on the development of the Heidelberg slit-scan flow cytometer. Time-resolved measurement of the fluorescence intensity along the chromosome axis can be registered simultaneously for two parameters when the chromosome axis can be registered simultaneously for two parameters when the chromosome passes perpendicularly through a narrowly focused laser beam combined by a detection slit in the image plane. So far automated data analysis has been performed off-line on a PC. In its final performance, the Heidelberg slit-scan flow cytometer will achieve on-line data analysis that allows an electro-acoustical sorting of chromosomes of interest. Interest is high in the agriculture field to study chromosome aberrations that influence the size of litters in pig (Sus scrofa domestica) breeding. Slit-scan measurements have been performed to characterize chromosomes of pigs; we present results for chromosome 1 and a translocation chromosome 6/15.

  7. Sources of salmonellae in an uninfected commercially-processed broiler flock.

    PubMed Central

    Rigby, C E; Pettit, J R; Baker, M F; Bentley, A H; Salomons, M O; Lior, H

    1980-01-01

    Cultural monitoring was used to study the incidence and sources of salmonellae in a 4160 bird broiler flock during the growing period, transport and processing in a commercial plant. No salmonellae were isolated from any of 132 litter samples of 189 chickens cultured during the seven-week growing period, even though nest litter samples from four of the eight parent flocks yielded salmonellae and Salmonella worthington was isolated from the meat meal component of the grower ration. On arrival at the plant, 2/23 birds sampled carried S. infantis on their feathers, although intestinal cultures failed to yield salmonellae. Three of 18 processed carcasses samples yielded salmonellae (S. infantis, S. heidelberg, S. typhimurium var copenhagen). The most likely source of these salmonellae was the plastic transport crates, since 15/107 sampled before the birds were loaded yielded salmonellae (S. infantis, S. typhimurium). The crate washer at the plant did not reduce the incidence of Salmonella-contaminated crates, since 16/116 sampled after washing yielded salmonellae (S. infantis, S. typhimurium, S. heidelberg, S. schwarzengrund, S. albany). PMID:7427774

  8. Three-dimensional Segmentation of Retinal Cysts from Spectral-domain Optical Coherence Tomography Images by the Use of Three-dimensional Curvelet Based K-SVD.

    PubMed

    Esmaeili, Mahdad; Dehnavi, Alireza Mehri; Rabbani, Hossein; Hajizadeh, Fedra

    2016-01-01

    This paper presents a new three-dimensional curvelet transform based dictionary learning for automatic segmentation of intraretinal cysts, most relevant prognostic biomarker in neovascular age-related macular degeneration, from 3D spectral-domain optical coherence tomography (SD-OCT) images. In particular, we focus on the Spectralis SD-OCT (Heidelberg Engineering, Heidelberg, Germany) system, and show the applicability of our algorithm in the segmentation of these features. For this purpose, we use recursive Gaussian filter and approximate the corrupted pixels from its surrounding, then in order to enhance the cystoid dark space regions and future noise suppression we introduce a new scheme in dictionary learning and take curvelet transform of filtered image then denoise and modify each noisy coefficients matrix in each scale with predefined initial 3D sparse dictionary. Dark pixels between retinal pigment epithelium and nerve fiber layer that were extracted with graph theory are considered as cystoid spaces. The average dice coefficient for the segmentation of cystoid regions in whole 3D volume and with-in central 3 mm diameter on the MICCAI 2015 OPTIMA Cyst Segmentation Challenge dataset were found to be 0.65 and 0.77, respectively. PMID:27563573

  9. Hans Küpper discusses science and venture capital.

    PubMed

    Küpper, Hans

    2004-11-01

    Hans Küpper has over 30 years of experience in the biotechnology industry in areas from research to R&D management, technology assessment and business acquisitions. He received his PhD in 1974 from the University of Heidelberg. After additional academic research at the Massachusetts Institute of Technology in the USA and at the University of Heidelberg, Germany, he joined Biogen in 1980. Here, he held various R&D positions, the last of which was Assistant Research Director. In 1985, he joined Behringwerke AG, Marburg, to build up and head the company's Molecular Biology Department and thereafter became Head of R&D of the Immunology/Oncology Business Unit. In 1999 he joined Global Life Science Ventures at their Munich office. Dr Küpper is the author of numerous publications and patents/applications and has also served as a consultant to the Pharmaceutical Industry and the European Commission. He is a board member of several early stage companies in the life sciences. PMID:15501722

  10. The circumstellar structure of the Be shell star phi Per. I. Data analysis

    NASA Astrophysics Data System (ADS)

    Štefl, S.; Hummel, W.; Rivinius, Th.

    2000-06-01

    We present new phase resolved observations of emission lines of the Be binary phi Per. Analyzing the orbital phase variations in the He I emission features we find strong arguments that the feature as a whole originates in the outer parts of the disk around the primary star. In addition to the He I 6678 and 5876 lines, the emission features with orbital phase variations were detected in three more He I lines. The observations are in agreement with the scenario of Poeckert and others, in which the outer parts of an axisymmetric disk are illuminated by the radiation of the secondary. The observations after 1996 are consistent with a growing global density inhomogeneity in the circumprimary disk as it occurs in disks of single Be stars. The combination of the illumination effect and the increasing density inhomogeneity make phi Per an ideal laboratory to study density perturbations of circumstellar disks of Be stars in more detail. Based on observations collected at the Ond\\v{r}ejov Observatory (of the Academy of Sciences of the Czech Republic), Heidelberg Observatory, German-Spanish Astronomical Center (DSAZ) - Calar Alto (operated by the Max-Plank-Institut für Astronomie Heidelberg jointly with the Spanish National Commission for Astronomy) and Observatoire de Haute-Provence (OHP; CNRS, France)}

  11. Distributions of off-diagonal scattering matrix elements: Exact results

    SciTech Connect

    Nock, A. Kumar, S. Sommers, H.-J. Guhr, T.

    2014-03-15

    Scattering is a ubiquitous phenomenon which is observed in a variety of physical systems which span a wide range of length scales. The scattering matrix is the key quantity which provides a complete description of the scattering process. The universal features of scattering in chaotic systems is most generally modeled by the Heidelberg approach which introduces stochasticity to the scattering matrix at the level of the Hamiltonian describing the scattering center. The statistics of the scattering matrix is obtained by averaging over the ensemble of random Hamiltonians of appropriate symmetry. We derive exact results for the distributions of the real and imaginary parts of the off-diagonal scattering matrix elements applicable to orthogonally-invariant and unitarily-invariant Hamiltonians, thereby solving a long standing problem. -- Highlights: •Scattering problem in complex or chaotic systems. •Heidelberg approach to model the chaotic nature of the scattering center. •A novel route to the nonlinear sigma model based on the characteristic function. •Exact results for the distributions of off-diagonal scattering-matrix elements. •Universal aspects of the scattering-matrix fluctuations.

  12. Diagnosing Undersampling in Monte Carlo Eigenvalue and Flux Tally Estimates

    SciTech Connect

    Perfetti, Christopher M; Rearden, Bradley T

    2015-01-01

    This study explored the impact of undersampling on the accuracy of tally estimates in Monte Carlo (MC) calculations. Steady-state MC simulations were performed for models of several critical systems with varying degrees of spatial and isotopic complexity, and the impact of undersampling on eigenvalue and fuel pin flux/fission estimates was examined. This study observed biases in MC eigenvalue estimates as large as several percent and biases in fuel pin flux/fission tally estimates that exceeded tens, and in some cases hundreds, of percent. This study also investigated five statistical metrics for predicting the occurrence of undersampling biases in MC simulations. Three of the metrics (the Heidelberger-Welch RHW, the Geweke Z-Score, and the Gelman-Rubin diagnostics) are commonly used for diagnosing the convergence of Markov chains, and two of the methods (the Contributing Particles per Generation and Tally Entropy) are new convergence metrics developed in the course of this study. These metrics were implemented in the KENO MC code within the SCALE code system and were evaluated for their reliability at predicting the onset and magnitude of undersampling biases in MC eigenvalue and flux tally estimates in two of the critical models. Of the five methods investigated, the Heidelberger-Welch RHW, the Gelman-Rubin diagnostics, and Tally Entropy produced test metrics that correlated strongly to the size of the observed undersampling biases, indicating their potential to effectively predict the size and prevalence of undersampling biases in MC simulations.

  13. Tracking discontinuities in hyperbolic conservation laws with spectral accuracy

    NASA Astrophysics Data System (ADS)

    Touil, H.; Hussaini, M. Y.; Sussman, M.

    2007-08-01

    It is well known that the spectral solutions of conservation laws have the attractive distinguishing property of infinite-order convergence (also called spectral accuracy) when they are smooth (e.g., [C. Canuto, M.Y. Hussaini, A. Quarteroni, T.A. Zang, Spectral Methods for Fluid Dynamics, Springer-Verlag, Heidelberg, 1988; J.P. Boyd, Chebyshev and Fourier Spectral Methods, second ed., Dover, New York, 2001; C. Canuto, M.Y. Hussaini, A. Quarteroni, T.A. Zang, Spectral Methods: Fundamentals in Single Domains, Springer-Verlag, Berlin Heidelberg, 2006]). If a discontinuity or a shock is present in the solution, this advantage is lost. There have been attempts to recover exponential convergence in such cases with rather limited success. The aim of this paper is to propose a discontinuous spectral element method coupled with a level set procedure, which tracks discontinuities in the solution of nonlinear hyperbolic conservation laws with spectral convergence in space. Spectral convergence is demonstrated in the case of the inviscid Burgers equation and the one-dimensional Euler equations.

  14. Evaluation of Retinal and Choroidal Thickness in Fuchs' Uveitis Syndrome

    PubMed Central

    Ozsutcu, Mustafa

    2016-01-01

    Purpose. We aimed to investigate retinal and choroidal thickness in the eyes of patients with Fuchs' uveitis syndrome (FUS). Methods. Fifteen patients with unilateral FUS and 20 healthy control subjects were enrolled. Spectral domain optical coherence tomography (Spectralis HRA+OCT, 870 nm; Heidelberg Engineering, Heidelberg, Germany) was used to obtain retinal and choroidal thickness measurements. The retinal nerve fiber layer (RNFL) thickness, macular thickness, and choroidal thickness of the eyes with FUS were compared with the unaffected eye and the eyes of healthy control subjects. Results. The mean choroidal thickness at fovea and at each point within the horizontal nasal and temporal quadrants at 500 μm intervals to a distance of 1500 µm from the foveal center was significantly thinner in the affected eye of FUS patients compared with the unaffected eye of FUS patients or the eyes of healthy control subjects. However, there were no significant differences in RNFL or macular thickness between groups. Conclusions. Affected eyes in patients with FUS tend to have thinner choroids as compared to eyes of unaffected fellow eyes and healthy individuals, which might be a result of the chronic inflammation associated with the disease. PMID:27579176

  15. Three-dimensional Segmentation of Retinal Cysts from Spectral-domain Optical Coherence Tomography Images by the Use of Three-dimensional Curvelet Based K-SVD

    PubMed Central

    Esmaeili, Mahdad; Dehnavi, Alireza Mehri; Rabbani, Hossein; Hajizadeh, Fedra

    2016-01-01

    This paper presents a new three-dimensional curvelet transform based dictionary learning for automatic segmentation of intraretinal cysts, most relevant prognostic biomarker in neovascular age-related macular degeneration, from 3D spectral-domain optical coherence tomography (SD-OCT) images. In particular, we focus on the Spectralis SD-OCT (Heidelberg Engineering, Heidelberg, Germany) system, and show the applicability of our algorithm in the segmentation of these features. For this purpose, we use recursive Gaussian filter and approximate the corrupted pixels from its surrounding, then in order to enhance the cystoid dark space regions and future noise suppression we introduce a new scheme in dictionary learning and take curvelet transform of filtered image then denoise and modify each noisy coefficients matrix in each scale with predefined initial 3D sparse dictionary. Dark pixels between retinal pigment epithelium and nerve fiber layer that were extracted with graph theory are considered as cystoid spaces. The average dice coefficient for the segmentation of cystoid regions in whole 3D volume and with-in central 3 mm diameter on the MICCAI 2015 OPTIMA Cyst Segmentation Challenge dataset were found to be 0.65 and 0.77, respectively. PMID:27563573

  16. Optical coherence tomography and confocal endomicroscopy for rhinologic pathologies: a pilot study

    NASA Astrophysics Data System (ADS)

    Olzowy, B.; Starke, N.; Schuldt, T.; Hüttmann, G.; Lankenau, E.; Just, T.

    2013-06-01

    Optical coherence tomography (OCT) and confocal endomicroscopy (CEM) have a well-established potential for early diagnosis of pre-malignant and early malignant lesions of the upper aerodigestive tract mucosa. Additional applications in ENT-diagnostics might facilitate a more widespread use by making the investment into the devices more economic. Both imaging techniques might also provide valuable information in nasal pathologies. OCT images were generated with a surgical microscope (Möller-Wedel Hi-R 1000) with an integrated high-speed-OCT camera (Optomedical GmbH). For the CEM a Heidelberg Retina tomograph II scanner (Heidelberg Engineering GmbH) was used. Both during sinus surgery in vivo and from removed material ex vivo OCT and CEM images were taken and correlated with histopathological analysis after hematoxylin and eosin staining. Patients with inverted papillomas and chronic rhinosinusitis (CRS) were evaluated. Inverted papillomas show a variably thick epithelial layer on OCT and densely packed epithelial cells on CEM. They can be clearly distinguished from nasal polyps that show a very thin epithelial layer upon loose subepithelial tissue. In CRS CEM can distinguish areas with intact from areas with destroyed ciliated epithelium by directly visualizing ciliary movement. OCT sometimes showed thin superficial dense structures that might correspond to biofilms. OCT and CEM might provide valuable information in the follow-up care of patients with inverted papillomas and in diagnostics of CRS.

  17. Significance of the disc damage likelihood scale objectively measured by a non-mydriatic fundus camera in preperimetric glaucoma

    PubMed Central

    Pahlitzsch, Milena; Torun, Necip; Erb, Carl; Bruenner, Jeanette; Maier, Anna Karina B; Gonnermann, Johannes; Bertelmann, Eckart; Klamann, Matthias K J

    2015-01-01

    Purpose To assess the correlation between the disc damage likelihood scale (DDLS) objectively measured by a non-mydriatic fundus camera, Heidelberg Retina Tomograph 3, and optic coherence tomography in preperimetric glaucoma. Methods One-hundred-twenty-five patients with preperimetric primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (n=30) were included (mean age 58.9±15.9 years). All three devices graded the optic disc topography: Diagnosis 1 was defined as “outside normal limits”, while Diagnosis 2 as “borderline or outside normal limits”. Results For Diagnosis 1, a significant correlation was shown between DDLS and Moorfields regression analysis (P=0.022), and for Diagnosis 2 with glaucoma probability score analysis (P=0.024), in POAG. In pseudoexfoliation glaucoma, DDLS did not correlate significantly with Heidelberg Retina Tomograph 3 and optic coherence tomography. Regarding the area under the curve the highest predictive power was demonstrated by the objective DDLS (0.513–0.824) compared to Burk (0.239–0.343) and Mikelberg (0.093–0.270) coefficients. Conclusions The DDLS showed a significant correlation to the Moorfields regression analysis in preperimetric POAG. The objective DDLS showed the highest predictive power and thus is an additive tool in diagnosing preperimetric glaucoma. PMID:26640365

  18. The HUPO PSI's molecular interaction format--a community standard for the representation of protein interaction data.

    PubMed

    Hermjakob, Henning; Montecchi-Palazzi, Luisa; Bader, Gary; Wojcik, Jérôme; Salwinski, Lukasz; Ceol, Arnaud; Moore, Susan; Orchard, Sandra; Sarkans, Ugis; von Mering, Christian; Roechert, Bernd; Poux, Sylvain; Jung, Eva; Mersch, Henning; Kersey, Paul; Lappe, Michael; Li, Yixue; Zeng, Rong; Rana, Debashis; Nikolski, Macha; Husi, Holger; Brun, Christine; Shanker, K; Grant, Seth G N; Sander, Chris; Bork, Peer; Zhu, Weimin; Pandey, Akhilesh; Brazma, Alvis; Jacq, Bernard; Vidal, Marc; Sherman, David; Legrain, Pierre; Cesareni, Gianni; Xenarios, Ioannis; Eisenberg, David; Steipe, Boris; Hogue, Chris; Apweiler, Rolf

    2004-02-01

    A major goal of proteomics is the complete description of the protein interaction network underlying cell physiology. A large number of small scale and, more recently, large-scale experiments have contributed to expanding our understanding of the nature of the interaction network. However, the necessary data integration across experiments is currently hampered by the fragmentation of publicly available protein interaction data, which exists in different formats in databases, on authors' websites or sometimes only in print publications. Here, we propose a community standard data model for the representation and exchange of protein interaction data. This data model has been jointly developed by members of the Proteomics Standards Initiative (PSI), a work group of the Human Proteome Organization (HUPO), and is supported by major protein interaction data providers, in particular the Biomolecular Interaction Network Database (BIND), Cellzome (Heidelberg, Germany), the Database of Interacting Proteins (DIP), Dana Farber Cancer Institute (Boston, MA, USA), the Human Protein Reference Database (HPRD), Hybrigenics (Paris, France), the European Bioinformatics Institute's (EMBL-EBI, Hinxton, UK) IntAct, the Molecular Interactions (MINT, Rome, Italy) database, the Protein-Protein Interaction Database (PPID, Edinburgh, UK) and the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING, EMBL, Heidelberg, Germany). PMID:14755292

  19. Comparison of Structural and Functional Ocular Outcomes Between 14- and 70 Day Bed Rest

    NASA Technical Reports Server (NTRS)

    Cromwell, R. L.; Taibbi, G.; Zanello, S. B.; Yarbough, P. O.; Ploutz-Snyder, R. J.; Vizzeri, G.

    2016-01-01

    Purpose: To compare structural and functional ocular outcomes in healthy human subjects undergoing 14- and/or 70-day head-down-tilt bed rest (HDTBR). We hypothesized the amount of HDTBR-induced ocular changes be affected by the HDTBR duration. Methods: The studies were conducted at the NASA Flight Analogs Research Unit, The University of Texas Medical Branch at Galveston, Galveston, TX. Participants were selected using NASA standard screening procedures. Standardized NASA screening procedures and bed rest conditions (e.g., strict sleep-wake cycle, standardized diet, continuous video monitoring) were implemented in both studies. Participants maintained a 6deg HDTBR position for 14 and/or 70 consecutive days and did not engage in exercise. Weekly ophthalmological examinations were conducted in the sitting (pre/post-bed rest only) and HDT positions. Ocular outcomes of interest included: near best-corrected visual acuity (BCVA); spherical equivalent, as determined by cycloplegic autorefraction; Goldmann applanation tonometry and iCare (Icare Finland Oy, Espoo, Finland) intraocular pressure (IOP) measurement; color vision; red dot test; modified Amsler grid test; confrontational visual field; stereoscopic color fundus photography; Spectralis OCT (Heidelberg Engineering, GmbH, Heidelberg, Germany) retinal nerve fiber layer thickness (RNFLT), peripapillary and macular retinal thicknesses. Mixed-effects linear models were used to compare pre- and post-HDTBR observations between 14- and 70-day HDTBR for our continuously scaled outcomes.

  20. Dipolar Effects in an Ultracold Gas of LiCs Molecules

    NASA Astrophysics Data System (ADS)

    Weidemueller, Matthias

    2011-05-01

    Recently, there has been important progress in the investigation of ultracold polar molecules in the absolute ground state, thus opening intriguing perspectives for strongly correlated quantum systems under the influence of long-range dipolar forces. We have studied the formation of LiCs molecules via photoassociation (PA) in a double-species magneto-optical trap. The LiCs dimer is a particularly promising candidate for observing dipolar effects, as it possesses the largest dipole moment of all alkali dimers (5.5 Debye in the ground state). Ultracold LiCs molecules in the absolute rovibrational ground state are formed by a single photo-association step. The dipole moment of ground state levels is determined by Stark spectroscopy and was found to be in excellent agreement with the theoretical predictions. Vibrational redistribution due to spontaneous emission and blackbody radiation is observed and compared a rate-equation model.In collaboration with Johannes Deiglmayr, Marc Repp, University of Heidelberg; Roland Wester, University of Innsbruck; and Olivier Dulieu, Laboratoire Aime Cotton. Work was supported by DFG and ESF in the framework of the Eurocores EuroQUAM as well as the Heidelberg Center for Quantum Dynamics.