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Sample records for atr wg-mox fuel

  1. ATR WG-MOX Fuel Pellet Burnup Measurement by Monte Carlo - Mass Spectrometric Method

    SciTech Connect

    Chang, Gray Sen I

    2002-10-01

    This paper presents a new method for calculating the burnup of nuclear reactor fuel, the MCWO-MS method, and describes its application to an experiment currently in progress to assess the suitability for use in light-water reactors of Mixed-OXide (MOX) fuel that contains plutonium derived from excess nuclear weapons material. To demonstrate that the available experience base with Reactor-Grade Mixed uranium-plutonium OXide (RGMOX) can be applied to Weapons-Grade (WG)-MOX in light water reactors, and to support potential licensing of MOX fuel made from weapons-grade plutonium and depleted uranium for use in United States reactors, an experiment containing WG-MOX fuel is being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory. Fuel burnup is an important parameter needed for fuel performance evaluation. For the irradiated MOX fuel’s Post-Irradiation Examination, the 148Nd method is used to measure the burnup. The fission product 148Nd is an ideal burnup indicator, when appropriate correction factors are applied. In the ATR test environment, the spectrum-dependent and burnup-dependent correction factors (see Section 5 for detailed discussion) can be substantial in high fuel burnup. The validated Monte Carlo depletion tool (MCWO) used in this study can provide a burnup-dependent correction factor for the reactor parameters, such as capture-to-fission ratios, isotopic concentrations and compositions, fission power, and spectrum in a straightforward fashion. Furthermore, the correlation curve generated by MCWO can be coupled with the 239Pu/Pu ratio measured by a Mass Spectrometer (in the new MCWO-MS method) to obtain a best-estimate MOX fuel burnup. A Monte Carlo - MCWO method can eliminate the generation of few-group cross sections. The MCWO depletion tool can analyze the detailed spatial and spectral self-shielding effects in UO2, WG-MOX, and reactor-grade mixed oxide (RG-MOX) fuel pins. The MCWO-MS tool only

  2. Monte Carlo boundary source approach in MOX fuel test capsule design

    SciTech Connect

    Chang, G.S.; Ryskamp, J.M.

    1999-09-01

    To demonstrate that the differences between weapons-grade (WG) mixed oxide (MOX) and reactor-grade MOX fuel are minimal, and therefore the commercial MOX experience base is applicable, an average power test (6 to 10 kW/ft) of WG MOX fuel was inserted into the Advanced Test Reactor (ATR) in January 1998. A high-power test (10 to 15 kW/ft) of WG MOX fuel in ATR is being fabricated as a follow-on to the average-power test. Two MOX capsules with 8.9 GWd/t burnup were removed from ATR on September 13, 1998, and replaced by two fresh WG MOX fuel capsules in regions with less thermal neutron flux (top-1 and bottom-1, which are away from the core center). To compensate for {sup 239}Pu depletion, which causes the linear heat generation rates (LHGRs) to decrease, the INCONEL shield was replaced by an aluminum shield in the phase-II irradiation. The authors describe and compare the results of the detailed MCNP ATR quarter core model (QCM) and isolated box model with boundary source (IBMBS). Physics analysis were performed with these two different models to provide the neutron/fission heat rate distribution data in the WG MOX fuel test assembly, with INCONEL and aluminum shrouds, located in the small I-24 hole of ATR.

  3. Neutron flux and spectrum variation in a MOX fuel experiment

    SciTech Connect

    Chang, G.S.; Rogers, J.W.; Ryskamp, J.M.

    1999-07-01

    In support of potential licensing of mixed-oxide (MOX) fuel made from weapons-grade (WG) plutonium and depleted uranium for use in US reactors, an experiment containing WG-MOX fuel has been designed and is being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory. A simple, uninstrumented, test assembly containing nine MOX fuel capsules with neutron monitor wires was inserted into the ATR. Important neutronics parameters were computed using novel Monte Carlo methods. The purpose is to show that neutron monitor measurements have validated the new methodology.

  4. ATR Spent Fuel Options Study

    SciTech Connect

    Connolly, Michael James; Bean, Thomas E.; Brower, Jeffrey O.; Luke, Dale E.; Patterson, M. W.; Robb, Alan K.; Sindelar, Robert; Smith, Rebecca E.; Tonc, Vincent F.; Tripp, Julia L.; Winston, Philip L.

    2017-01-01

    The Advanced Test Reactor (ATR) is a materials and fuels test nuclear reactor that performs irradiation services for the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), Naval Reactors, the National Nuclear Security Administration (NNSA), and other research programs. ATR achieved initial criticality in 1967 and is expected to operate in support of needed missions until the year 2050 or beyond. It is anticipated that ATR will generate approximately 105 spent nuclear fuel (SNF) elements per year through the year 2050. Idaho National Laboratory (INL) currently stores 2,008 ATR SNF elements in dry storage, 976 in wet storage, and expects to have 1,000 elements in wet storage before January 2017. A capability gap exists at INL for long-term (greater than the year 2050) management, in compliance with the Idaho Settlement Agreement (ISA), of ATR SNF until a monitored retrievable geological repository is open. INL has significant wet and dry storage capabilities that are owned by the DOE Office of Environmental Management (EM) and operated and managed by Fluor Idaho, which include the Idaho Nuclear Technology and Engineering Center’s (INTEC’s) CPP-666, CPP-749, and CPP-603. In addition, INL has other capabilities owned by DOE-NE and operated and managed by Battelle Energy Alliance, LLC (BEA), which are located at the Materials and Fuel Complex (MFC). Additional storage capabilities are located on the INL Site at the Naval Reactors Facility (NRF). Current INL SNF management planning, as defined in the Fluor Idaho contract, shows INTEC dry fuel storage, which is currently used for ATR SNF, will be nearly full after transfer of an additional 1,000 ATR SNF from wet storage. DOE-NE tasked BEA with identifying and analyzing options that have the potential to fulfill this capability gap. BEA assembled a team comprised of SNF management experts from Fluor Idaho, Savannah River Site (SRS), INL/BEA, and the MITRE Corp with an objective of developing and analyzing

  5. Detailed axial power profiles in a MOX fuel experiment in the Advanced Test Reactor

    SciTech Connect

    Chang, G.; Ryskamp, J.M.

    1998-12-31

    The US Department of Energy (DOE) has chosen two options to dispose of surplus weapons-grade (WG) plutonium (WGPu). One option is to burn the WGPu in mixed-oxide (MOX) fuel in light water reactors. An average power test (<10 kW/ft) of WG-MOX fuel was inserted in the Advanced Test Reactor (ATR) in February 1998. A high power test (<15 kW/ft) of WG-MOX fuel in ATR will follow the average-power test. The ability to accurately predict fuel power is essential in the high-power WG-MOX fuel capsule design for the test in ATR. Detailed fission power and temperature profiles may influence gallium migration in WG-MOX fuel pins. Most of the fission heat generated in the MOX fuel capsules will transfer radially to the water coolant. However, because of the short length (15.24 cm) of the MOX fuel pellet stacks, some of the fission heat will transfer through the end pellets axially. Compounded with peak fission power local-to-average ratios (LTAR) at the ends of MOX fuel stacks, the hot spot created may exceed the design limit. Therefore, the prediction of the axial fission power profiles over the MOX fuel stacks at the beginning of life (BOL) and end of life (EOL) are important for MOX fuel performance analysis and capsule design for testing in ATR. Continuous-energy MCNP linked with ORIGEN2 can generate the burnup-dependent cross sections and fission power distribution for fuel burnup analysis while accurately including the effects of self-shielding. This approach is very important for the prediction of plutonium content and LTAR in MOX fuel pellet stacks with HfO{sub 2} ends. MCWO can accurately determine fuel pin power distributions in the ATR experiment when the MOX fuel and HfO{sub 2} are depleted simultaneously. This is significant because the authors quickly provided the customer with the required detailed power distributions within the MOX pins using the new approach. The MOX fuel pin with HfO{sub 2} can flatten the axial power profiles from BOL to EOL and meet the MOX

  6. Depletion analysis of mixed-oxide fuel pins in light water reactors and the Advanced Test Reactor

    SciTech Connect

    Chang, G.S.; Ryskamp, J.M.

    2000-03-01

    An experiment containing weapons-grade mixed-oxide (WG-MOX) fuel has been designed and is being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The ability to accurately predict fuel pin performance is an essential requirement for the MOX fuel test assembly design. Detailed radial fission power and temperature profile effects and fission gas release in the fuel pin are a function of the fuel pin's temperature, fission power, and fission product ad actinide concentration profiles. In addition, the burnup-dependent profile analyses in irradiated fuel pins is important for fuel performance analysis to support the potential licensing of the MOX fuel made from WG-plutonium and depleted uranium for use in US reactors. The MCNP Coupling With ORIGEN2 burnup calculation code (MCWO) can analyze the detailed burnup profiles of WG-MOX and reactor-grade mixed-oxide (RG-MOX) fuel pins. The validated code MCWO can provide the best-estimate neutronic characteristics of fuel burnup performance analysis. Applying this capability with a new minicell method allows calculation of detailed nuclide concentration and power distributions within the MOX pins as a function of burnup. This methodology was applied to MOX fuel in a commercial pressurized water reactor and in an experiment currently being irradiated in the ATR. The prediction of nuclide concentration profiles and power distributions in irradiated MOX plus via this new methodology can provide insights into MOX fuel performance.

  7. Weapons-Grade MOX Fuel Burnup Characteristics in Advanced Test Reactor Irradiation

    SciTech Connect

    G. S. Chang

    2006-07-01

    Mixed oxide (MOX) test capsules prepared with weapons-derived plutonium have been irradiated to a burnup of 50 GWd/t. The MOX fuel was fabricated at Los Alamos National Laboratory (LANL) by a master-mix process and has been irradiated in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). Previous withdrawals of the same fuel have occurred at 9, 21, 30, 40, and 50 GWd/t. Oak Ridge National Laboratory (ORNL) manages this test series for the Department of Energy’s Fissile Materials Disposition Program (FMDP). A UNIX BASH (Bourne Again SHell) script CMO has been written and validated at the Idaho National Laboratory (INL) to couple the Monte Carlo transport code MCNP with the depletion and buildup code ORIGEN-2 (CMO). The new Monte Carlo burnup analysis methodology in this paper consists of MCNP coupling through CMO with ORIGEN-2(MCWO). MCWO is a fully automated tool that links the Monte Carlo transport code MCNP with the radioactive decay and burnup code ORIGEN-2. The fuel burnup analyses presented in this study were performed using MCWO. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations for the ATR small I-irradiation test position. The purpose of this report is to validate both the Weapons-Grade Mixed Oxide (WG-MOX) test assembly model and the new fuel burnup analysis methodology by comparing the computed results against the neutron monitor measurements and the irradiated WG-MOX post irradiation examination (PIE) data.

  8. ATR PDQ and MCWO Fuel Burnup Analysis Codes Evaluation

    SciTech Connect

    G.S. Chang; P. A. Roth; M. A. Lillo

    2009-11-01

    The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) is being studied to determine the feasibility of converting it from the highly enriched Uranium (HEU) fuel that is currently uses to low enriched Uranium (LEU) fuel. In order to achieve this goal, it would be best to qualify some different computational methods than those that have been used at ATR for the past 40 years. This paper discusses two methods of calculating the burnup of ATR fuel elements. The existing method, that uses the PDQ code, is compared to a modern method that uses A General Monte Carlo N-Particle Transport Code (MCNP) combined with the Origen2.2 code. This modern method, MCNP with ORIGEN2.2 (MCWO), is found to give excellent agreement with the existing method (PDQ). Both of MCWO and PDQ are also in a very good agreement to the 235U burnup data generated by an analytical method.

  9. Methodology for the Weapons-Grade MOX Fuel Burnup Analysis in the Advanced Test Reactor

    SciTech Connect

    G. S. Chang

    2005-08-01

    A UNIX BASH (Bourne Again SHell) script CMO has been written and validated at the Idaho National Laboratory (INL) to couple the Monte Carlo transport code MCNP with the depletion and buildup code ORIGEN-2 (CMO). The new Monte Carlo burnup analysis methodology in this paper consists of MCNP coupling through CMO with ORIGEN-2, and is therefore called the MCWO. MCWO is a fully automated tool that links the Monte Carlo transport code MCNP with the radioactive decay and burnup code ORIGEN-2. MCWO is capable of handling a large number of fuel burnup and material loading specifications, Advanced Test Reactor (ATR) lobe powers, and irradiation time intervals. MCWO processes user input that specifies the system geometry, initial material compositions, feed/removal specifications, and other code-specific parameters. Calculated results from MCNP, ORIGEN-2, and data process module calculations are output in succession as MCWO executes. The principal function of MCWO is to transfer one-group cross-section and flux values from MCNP to ORIGEN-2, and then transfer the resulting material compositions (after irradiation and/or decay) from ORIGEN-2 back to MCNP in a repeated, cyclic fashion. The basic requirements of MCWO are a working MCNP input file and some additional input parameters; all interaction with ORIGEN-2 as well as other calculations are performed by CMO. This paper presents the MCWO-calculated results for the Reduced Enrichment Research and Test Reactor (RERTR) experiments RERTR-1 and RERTR-2 as well as the Weapons-Grade Mixed Oxide (WG-MOX) fuel testing in ATR. Calculations performed for the WG-MOX test irradiation, which is managed by the Oak Ridge National Laboratory (ORNL), supports the DOE Fissile Materials Disposition Program (FMDP). The MCWO-calculated results are compared with measured data.

  10. AFC-1 Fuel Rodlet Fission Power Deposition Validation in ATR

    SciTech Connect

    G. S. Chang; M. A. Lillo; D. J. Utterbeck

    2008-11-01

    One of the viable options of long-term geological disposal of the nuclear power reactors generated spent fuel is to extract plutonium, the minor actinides (MA) and potentially long-lived fission products from the spent fuel and transmute them into short-lived or stable radionuclides in an appropriate reactor for the reduction of the radiological toxicity of the nuclear waste stream. An important component of that technology will be a non-fertile / low-fertile actinide transmutation fuel form containing the plutonium, neptunium, americium (and possibly curium) isotopes to be transmuted. Such advanced fuel forms, especially ones enriched in the long-life minor actinide (LLMA) elements (i.e., Np, Am, Cm), have minimal irradiation performance data available from which to establish a transmutation fuel form design. Recognizing these needs, an Advanced Fuel Cycle test series-1 (AFC-1) irradiation test on a variety of candidate fuel forms is now being conducted in Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The first advanced fuel experiment (AFC-1) has been finalized and the test assembly analyzed for insertion and irradiation in ATR. The ATR core consists of a serpentine and rotationally symmetric fuel assembly about the z-axis of the core center. The plan view of the ATR core configuration is shown in Fig. 5, in Ref. 1. A cadmium filter with a 0.178 cm (0.045") thickness and 121.5 cm (48") in length, is currently used in the actinide-fuel capsule design for the East Flux Trap (EFT) position in ATR, to depress the linear heat generation rate (LHGR) lower than the project’s 330 W/cm limit for the experimental fuel rodlets. The LHGR is proportional to the fission power deposited in the fuel rodlets from the neutron fissions. The fraction of the fission power generated from the neutron fission reactions deposited in the fuel rodlet is an important parameter for test assembly thermal analysis, which will be validated in this summary.

  11. Comparison of HEU and LEU Fuel Neutron Spectrum for ATR Fuel Element and ATR Flux-Trap Positions

    SciTech Connect

    G. S. Chang

    2008-10-01

    The Advanced Test Reactor (ATR) is a high power and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the high total core power and high neutron flux, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. An optimized low-enriched uranium (LEU) (U-10Mo) core conversion case, which can meet the project requirements, has been selected. However, LEU contains a significant quantity of high density U-238 (80.3 wt.%), which will harden the neutron spectrum in the core region. Based on the reference ATR HEU and the optimized LEU full core plate-by-plate (PBP) models, the present work investigates and compares the neutron spectra differences in the fuel element (FE), Northeast flux trap (NEFT), Southeast flux trap (SEFT), and East flux trap (EFT) positions. A detailed PBP MCNP ATR core model was developed and validated for fuel cycle burnup comparison analysis. The current ATR core with HEU U 235 enrichment of 93.0wt.% was used as the reference model. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm (20 mil). In this work, an optimized LEU (U-10Mo) core conversion case with a nominal fuel meat thickness of 0.330 mm (13 mil) and the U-235 enrichment of 19.7 wt.% was used to calculate the impact of the neutron spectrum in FE and FT positions. MCNP-calculated results show that the neutron spectrum in the LEU FE is slightly harder than in the HEU FE, as expected. However, when neutrons transport through water coolant and beryllium (Be), the neutrons are thermalized to an equilibrium neutron spectrum as a function of water volume fraction in the investigated FT positions. As a result, the neutron spectrum differences of the HEU and LEU in the NEFT, SEFT, and EFT are negligible. To demonstrate that the LEU core fuel cycle performance can meet the

  12. Analysis of the ATR fuel element swaging process

    SciTech Connect

    Richins, W.D.; Miller, G.K.

    1995-12-01

    This report documents a detailed evaluation of the swaging process used to connect fuel plates to side plates in Advanced Test Reactor (ATR) fuel elements. The swaging is a mechanical process that begins with fitting a fuel plate into grooves in the side plates. Once a fuel plate is positioned, a lip on each of two side plate grooves is pressed into the fuel plate using swaging wheels to form the joints. Each connection must have a specified strength (measured in terms, of a pullout force capacity) to assure that these joints do not fail during reactor operation. The purpose of this study is to analyze the swaging process and associated procedural controls, and to provide recommendations to assure that the manufacturing process produces swaged connections that meet the minimum strength requirement. The current fuel element manufacturer, Babcock and Wilcox (B&W) of Lynchburg, Virginia, follows established procedures that include quality inspections and process controls in swaging these connections. The procedures have been approved by Lockheed Martin Idaho Technologies and are designed to assure repeatability of the process and structural integrity of each joint. Prior to July 1994, ATR fuel elements were placed in the Hydraulic Test Facility (HTF) at the Idaho National Engineering Laboratory (AGNAIL), Test Reactor Area (TRA) for application of Boehmite (an aluminum oxide) film and for checking structural integrity before placement of the elements into the ATR. The results presented in this report demonstrate that the pullout strength of the swaged connections is assured by the current manufacturing process (with several recommended enhancements) without the need for- testing each element in the HTF.

  13. Natural convection heat transfer analysis of ATR fuel elements

    SciTech Connect

    Langerman, M.A.

    1992-05-01

    Natural convection air cooling of the Advanced Test Reactor (ATR) fuel assemblies is analyzed to determine the level of decay heat that can be removed without exceeding the melting temperature of the fuel. The study was conducted to assist in the level 2 PRA analysis of a hypothetical ATR water canal draining accident. The heat transfer process is characterized by a very low Rayleigh number (Ra {approx} 10{sup {minus}5}) and a high temperature ratio. Since neither data nor analytical models were available for Ra < 0.1, an analytical approach is presented based upon the integral boundary layer equations. All assumptions and simplifications are presented and assessed and two models are developed from similar foundations. In one model, the well-known Boussinesq approximations are employed, the results from which are used to assess the modeling philosophy through comparison to existing data and published analytical results. In the other model, the Boussinesq approximations are not used, thus making the model more general and applicable to the ATR analysis.

  14. MCWO - Linking MCNP And ORIGEN2 For Fuel Burnup Analysis

    SciTech Connect

    Gray S Chang

    2005-04-01

    The UNIX BASH (Bourne Again Shell) script MCWO has been developed at the Idaho National Engineering and Environment Laboratory (INEEL) to couple the Monte Carlo transport code MCNP with the depletion and buildup code ORIGEN2. MCWO is a fully automated tool that links the Monte Carlo transport code MCNP with the radioactive decay and burnup code ORIGEN2. MCWO can handle a large number of fuel burnup and material loading specifications, Advanced Test Reactor (ATR) powers, and irradiation time intervals. The program processes input from the user that specifies the system geometry, initial material compositions, feed/removal specifications, and other code-specific parameters. Calculated results from MCNP, ORIGEN2, and data process module calculations are then output successively as the code runs. The principal function of MCWO is to transfer one-group cross-section and flux values from MCNP to ORIGEN2, and then transfer the resulting material compositions (after irradiation and/or decay) from ORIGEN2 back to MCNP in a repeated, cyclic fashion. The basic requirement of the code is that the user have a working MCNP input file and other input parameters; all interaction with ORIGEN2 and other calculations are performed by UNIX BASH script MCWO. This paper presents the MCWO-calculated results of the RERTR-1 and -2 , and the Weapons-Grade Mixed Oxiide fuel (Wg-MOX) fuel experiments in ATR and compares the MCWO-calculated results with the measured data.

  15. Irradiaton of Metallic and Oxide Fuels for Actinide Transmutation in the ATR

    SciTech Connect

    Heather J. MacLean; Steven L. Hayes

    2007-09-01

    Metallic fuels containing minor actinides and rare earth additions have been fabricated and are prepared for irradiation in the ATR, scheduled to begin during the summer of 2007. Oxide fuels containing minor actinides are being fabricated and will be ready for irradiation in ATR, scheduled to begin during the summer of 2008. Fabrication and irradiation of these fuels will provide detailed studies of actinide transmutation in support of the Global Nuclear Energy Partnership. These fuel irradiations include new fuel compositions that have never before been tested. Results from these tests will provide fundamental data on fuel irradiation performance and will advance the state of knowledge for transmutation fuels.

  16. ATR LEU Fuel and Burnable Absorber Neutronics Performance Optimization by Fuel Meat Thickness Variation

    SciTech Connect

    G. S. Chang

    2007-09-01

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuel cycle burnup comparison analysis. Using the current HEU U 235 enrichment of 93.0 % as a baseline, an analysis can be performed to determine the low-enriched uranium (LEU) density and U-235 enrichment required in the fuel meat to yield an equivalent K-eff between the HEU core and the LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the U-235 loading in the LEU core, such that the differences in K-eff and heat flux profile between the HEU and LEU core can be minimized. The depletion methodology MCWO was used to calculate K-eff versus EFPDs in this paper. The MCWO-calculated results for the LEU cases with foil (U-10Mo) types demonstrated adequate excess reactivity such that the K-eff versus EFPDs plot is similar to the reference ATR HEU case. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm. In this work, the proposed LEU (U-10Mo) core conversion case with a nominal fuel meat thickness of 0.508 mm and the same U-235 enrichment (15.5 wt%) can be used to optimize the radial heat flux profile by varying the fuel plate thickness from 0.254 to 0.457 mm at the inner 4 fuel plates (1-4) and outer 4 fuel plates (16-19). In addition, a 0.7g of burnable absorber Boron-10 was added in the inner and outer plates to reduce the initial excess reactivity, and the inner/outer heat

  17. Diesel fuel processor for PEM fuel cells: Two possible alternatives (ATR versus SR)

    NASA Astrophysics Data System (ADS)

    Cutillo, A.; Specchia, S.; Antonini, M.; Saracco, G.; Specchia, V.

    There are large efforts in exploring the on-board reforming technologies, which would avoid the actual lack of hydrogen infrastructure and related safety issues. From this view point, the present work deals with the comparison between two different 10 kW e fuel processors (FP) systems for the production of hydrogen-rich fuel gas starting from diesel oil, based respectively on autothermal (ATR) and steam-reforming (SR) process and related CO clean-up technologies; the obtained hydrogen rich gas is fed to the PEMFC stack of an auxiliary power unit (APU). Based on a series of simulations with Matlab/Simulink, the two systems were compared in terms of FP and APU efficiency, hydrogen concentration fed to the FC, water balance and process scheme complexity. Notwithstanding a slightly higher process scheme complexity and a slightly more difficult water recovery, the FP based on the SR scheme, as compared to the ATR one, shows higher efficiency and larger hydrogen concentration for the stream fed to the PEMFC anode, which represent key issues for auxiliary power generation based on FCs as compared, e.g. to alternators.

  18. ATR LEU Monolithic Foil-Type Fuel with Integral Cladding Burnable Absorber – Neutronics Performance Evaluation

    SciTech Connect

    Gray Chang

    2012-03-01

    The Advanced Test Reactor (ATR), currently operating in the United States, is used for material testing at very high neutron fluxes. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting HEU driven reactor cores to low-enriched uranium (LEU) cores. The burnable absorber - 10B, was added in the inner and outer plates to reduce the initial excess reactivity, and to improve the peak ratio of the inner/outer heat flux. The present work investigates the LEU Monolithic foil-type fuel with 10B Integral Cladding Burnable Absorber (ICBA) design and evaluates the subsequent neutronics operating effects of this proposed fuel designs. The proposed LEU fuel specification in this work is directly related to both the RERTR LEU Development Program and the Advanced Test Reactor (ATR) LEU Conversion Project at Idaho National Laboratory (INL).

  19. Validation of ATR Fission Power Deposition Fraction in HEU and LEU Fuel Plates

    SciTech Connect

    G. S. Chang

    2008-09-01

    The Advanced Test Reactor (ATR) is a high power (250 MW), high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum unperturbed thermal neutron flux rating of 1.0 x 1015 n/cm2–s. Because of its high power and large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. A detailed plate-by-plate MCNP ATR full core model has been developed and validated for the low-enriched uranium (LEU) fuel conversion feasibility study. Using this model, an analysis has been performed to determine the LEU density and U-235 enrichment required in the fuel meat to yield equivalent K-eff versus effective full power days (EFPDs) between the HEU and LEU cores. This model has also been used to optimize U-235 content of the LEU core, minimizing the differences in K-eff and heat flux profile between the HEU and LEU cores at 115 MW total core power for 125 EFPDs. The LEU core conversion feasibility study evaluated foil type (U-10Mo) fuel with the LEU reference design of 19.7 wt% U-235 enrichment. The LEU reference design has a fixed fuel meat thickness of 0.330 mm and can sustain the same operating cycle length as the HEU fuel. Heat flux and fission power density are parameters that are proportional to the fraction of fission power deposited in fuel. Thus, the accurate determination of the fraction of fission power deposited in the fuel is important to ATR nuclear safety. In this work, a new approach was developed and validated, the Tally Fuel Cells Only (TFCO) method. This method calculates and compares the fission power deposition fraction between HEU and LEU fuel plates. Due to the high density of the U-10Mo LEU fuel, the fission ?-energy deposition fraction is 37.12%, which is larger than the HEU’s ?-energy deposition fraction of 19.7%. As a result, the fuel decay heat cooling will need to be improved

  20. Cadmium Depletion Impacts on Hardening Neutron6 Spectrum for Advanced Fuel Testing in ATR

    SciTech Connect

    Gray S. Chang

    2011-05-01

    For transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products effectively is in a fast neutron spectrum reactor. In the absence of a fast spectrum test reactor in the United States of America (USA), initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. A test region is achieved with a Cadmium (Cd) filter which can harden the neutron spectrum to a spectrum similar (although still somewhat softer) to that of the liquid metal fast breeder reactor (LMFBR). A fuel test loop with a Cd-filter has been installed within the East Flux Trap (EFT) of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). A detailed comparison analyses between the cadmium (Cd) filter hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum have been performed using MCWO. MCWO is a set of scripting tools that are used to couple the Monte Carlo transport code MCNP with the isotope depletion and buildup code ORIGEN-2.2. The MCWO-calculated results indicate that the Cd-filter can effectively flatten the Rim-Effect and reduce the linear heat rate (LHGR) to meet the advanced fuel testing project requirements at the beginning of irradiation (BOI). However, the filtering characteristics of Cd as a strong absorber quickly depletes over time, and the Cd-filter must be replaced for every two typical operating cycles within the EFT of the ATR. The designed Cd-filter can effectively depress the LHGR in experimental fuels and harden the neutron spectrum enough to adequately flatten the Rim Effect in the test region.

  1. Status Report on the Fabrication of Fuel Cladding Chemical Interaction Test Articles for ATR Irradiations

    SciTech Connect

    Field, Kevin G.; Howard, Richard H.

    2015-09-28

    FeCrAl alloys are a promising new class of alloys for light water reactor (LWR) applications due to their superior oxidation and corrosion resistance in high temperature environments. The current R&D efforts have focused on the alloy composition and processing routes to generate nuclear grade FeCrAl alloys with optimized properties for enhanced accident tolerance while maintaining properties needed for normal operation conditions. Therefore, the composition and processing routes must be optimized to maintain the high temperature steam oxidation (typically achieved by increasing the Cr and Al content) while still exhibiting properties conducive to normal operation in a LWR (such as radiation tolerance where reducing Cr content is favorable). Within this balancing act is the addition of understanding the influence on composition and processing routes on the FeCrAl alloys for fuel-cladding chemical interactions (FCCI). Currently, limited knowledge exists on FCCI for the FeCrAl-UO2 clad-fuel system. To overcome the knowledge gaps on the FCCI for the FeCrAl-UO2 clad-fuel system a series of fueled irradiation tests have been developed for irradiation in the Advanced Test Reactor (ATR) housed at the Idaho National Laboratory (INL). The first series of tests has already been reported. These tests used miniaturized 17x17 PWR fuel geometry rodlets of second-generation FeCrAl alloys fueled with industrial Westinghouse UO2 fuel. These rodlets were encapsulated within a stainless steel housing.To provide high fidelity experiments and more robust testing, a new series of rodlets have been developed deemed the Accident Tolerant Fuel Experiment #1 Oak Ridge National Laboratory FCCI test (ATF-1 ORNL FCCI). The main driving factor, which is discussed in detail, was to provide a radiation environment where prototypical fuel-clad interface temperatures are met while still maintaining constant contact between industrial fuel and the candidate cladding alloys

  2. Advanced turbine systems program conceptual design and product development Task 8.3 - autothermal fuel reformer (ATR). Topical report

    SciTech Connect

    1996-11-01

    Autothermal fuel reforming (ATR) consists of reacting a hydrocarbon fuel such as natural gas or diesel with steam to produce a hydrogen-rich {open_quotes}reformed{close_quotes} fuel. This work has been designed to investigate the fuel reformation and the product gas combustion under gas turbine conditions. The hydrogen-rich gas has a high flammability with a wide range of combustion stability. Being lighter and more reactive than methane, the hydrogen-rich gas mixes readily with air and can be burned at low fuel/air ratios producing inherently low emissions. The reformed fuel also has a low ignition temperature which makes low temperature catalytic combustion possible. ATR can be designed for use with a variety of alternative fuels including heavy crudes, biomass and coal-derived fuels. When the steam required for fuel reforming is raised by using energy from the gas turbine exhaust, cycle efficiency is improved because of the steam and fuel chemically recuperating. Reformation of natural gas or diesel fuels to a homogeneous hydrogen-rich fuel has been demonstrated. Performance tests on screening various reforming catalysts and operating conditions were conducted on a batch-tube reactor. Producing over 70 percent of hydrogen (on a dry basis) in the product stream was obtained using natural gas as a feedstock. Hydrogen concentration is seen to increase with temperature but less rapidly above 1300{degrees}F. The percent reforming increases as the steam to carbon ratio is increased. Two basic groups of reforming catalysts, nickel - and platinum-basis, have been tested for the reforming activity.

  3. Fabrication, inspection, and test plan for the Advanced Test Reactor (ATR) Mixed-Oxide (MOX) fuel irradiation project

    SciTech Connect

    Wachs, G.W.

    1997-11-01

    The Department of Energy (DOE) Fissile Materials Disposition Materials Disposition Program (FMDP) has announced that reactor irradiation of MOX fuel is one of the preferred alternatives for disposal of surplus weapons-usable plutonium (Pu). MOX fuel has been utilized domestically in test reactors and on an experimental basis in a number of Commercial Light Water Reactors (CLWRs). Most of this experience has been with Pu derived from spent low enriched uranium (LEU) fuel, known as reactor grade (RG) Pu. The MOX fuel test will be irradiated in the ATR to provide preliminary data to demonstrate that the unique properties of surplus weapons-derived or weapons-grade (WG) plutonium (Pu) do not compromise the applicability of this MOX experience base. In addition, the test will contribute experience with irradiation of gallium-containing fuel to the data base required for resolution of generic CLWR fuel design issues (ORNL/MD/LTR-76). This Fabrication, Inspection, and Test Plan (FITP) is a level 2 document as defined in the FMDP LWR MOX Fuel Irradiation Test Project Plan (ORNL/MD/LTR-78).

  4. Code Analyses Supporting PIE of Weapons-Grade MOX Fuel

    SciTech Connect

    Ott, Larry J; Bevard, Bruce Balkcom; Spellman, Donald J; McCoy, Kevin

    2010-01-01

    The U.S. Department of energy has decided to dispose of a portion of the nation's surplus weapons-grade plutonium by reconstituting it into mixed oxide (MOX) fuel and irradiating the fuel in commercial power reactors. Four lead test assemblies (LTAs) were manufactured with weapons-grade mixed oxide (WG-MOX) fuel and irradiated in the Catawba Nuclear Station Unit 1, to a maximum fuel rod burnup of ~47.3 GWd/MTHM. As part of the fuel qualification process, five rods with varying burnups and initial plutonium contents were selected from one assembly and shipped to the Oak Ridge National Laboratory (ORNL) for hot cell examination. ORNL has provided analytical support for the post-irradiation examination (PIE) of these rods via extensive fuel performance modeling which has aided in instrument settings and PIE data interpretation. The results of these fuel performance simulations are compared in this paper with available PIE data.

  5. Gamma-Ray Simulated Spectrum Deconvolution of a LaBr₃ 1-in. x 1-in. Scintillator for Nondestructive ATR Fuel Burnup On-Site Predictions

    SciTech Connect

    Navarro, Jorge; Ring, Terry A.; Nigg, David W.

    2015-03-01

    A deconvolution method for a LaBr₃ 1"x1" detector for nondestructive Advanced Test Reactor (ATR) fuel burnup applications was developed. The method consisted of obtaining the detector response function, applying a deconvolution algorithm to 1”x1” LaBr₃ simulated, data along with evaluating the effects that deconvolution have on nondestructively determining ATR fuel burnup. The simulated response function of the detector was obtained using MCNPX as well with experimental data. The Maximum-Likelihood Expectation Maximization (MLEM) deconvolution algorithm was selected to enhance one-isotope source-simulated and fuel- simulated spectra. The final evaluation of the study consisted of measuring the performance of the fuel burnup calibration curve for the convoluted and deconvoluted cases. The methodology was developed in order to help design a reliable, high resolution, rugged and robust detection system for the ATR fuel canal capable of collecting high performance data for model validation, along with a system that can calculate burnup and using experimental scintillator detector data.

  6. Gamma-Ray Simulated Spectrum Deconvolution of a LaBr₃ 1-in. x 1-in. Scintillator for Nondestructive ATR Fuel Burnup On-Site Predictions

    DOE PAGES

    Navarro, Jorge; Ring, Terry A.; Nigg, David W.

    2015-03-01

    A deconvolution method for a LaBr₃ 1"x1" detector for nondestructive Advanced Test Reactor (ATR) fuel burnup applications was developed. The method consisted of obtaining the detector response function, applying a deconvolution algorithm to 1”x1” LaBr₃ simulated, data along with evaluating the effects that deconvolution have on nondestructively determining ATR fuel burnup. The simulated response function of the detector was obtained using MCNPX as well with experimental data. The Maximum-Likelihood Expectation Maximization (MLEM) deconvolution algorithm was selected to enhance one-isotope source-simulated and fuel- simulated spectra. The final evaluation of the study consisted of measuring the performance of the fuel burnup calibrationmore » curve for the convoluted and deconvoluted cases. The methodology was developed in order to help design a reliable, high resolution, rugged and robust detection system for the ATR fuel canal capable of collecting high performance data for model validation, along with a system that can calculate burnup and using experimental scintillator detector data.« less

  7. A Feasibility Study to Determine Cooling Time and Burnup of ATR Fuel Using a Nondestructive Technique and Three Types of Gamma-ray Detectors

    SciTech Connect

    Jorge Navarro; Rahmat Aryaeinejad,; David W. Nigg

    2011-05-01

    A Feasibility Study to Determine Cooling Time and Burnup of ATR Fuel Using a Nondestructive Technique1 Rahmat Aryaeinejad, Jorge Navarro, and David W Nigg Idaho National Laboratory Abstract Effective and efficient Advanced Test Reactor (ATR) fuel management require state of the art core modeling tools. These new tools will need isotopic and burnup validation data before they are put into production. To create isotopic, burn up validation libraries and to determine the setup for permanent fuel scanner system a feasibility study was perform. The study consisted in measuring short and long cooling time fuel elements at the ATR canal. Three gamma spectroscopy detectors (HPGe, LaBr3, and HPXe) and two system configurations (above and under water) were used in the feasibility study. The first stage of the study was to investigate which detector and system configuration would be better suited for different scenarios. The second stage of the feasibility study was to create burnup and cooling time calibrations using experimental isotopic data collected and ORIGEN 2.2 burnup data. The results of the study establish that a better spectra resolution is achieve with an above the water configuration and that three detectors can be used in the permanent fuel scanner system for different situations. In addition it was conclude that a number of isotopic ratios and absolute measurements could be used to predict ATR fuel burnup and cooling times. 1This work was supported by the U.S. Depart¬ment of Energy (DOE) under Battelle Energy Alliance, LLC Contract No. DE-AC07-05ID14517.

  8. Irradiation of Metallic Fuels with Rare Earth Additions for Actinide Transmutation in the ATR. Experiment Description for AFC-2A and AFC-2B

    SciTech Connect

    S. L. Hayes; D. J. Utterbeck; T. A. Hyde

    2007-03-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing metallic transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the metallic fuel test series in progress in the ATR. This report documents the experiment description and test matrix of the proposed experiments and the Post Irradiation Examination (PIE) and fabrication schedule.

  9. Irradiation of Metallic Fuels with Rare Earth Additions for Actinide Transmutation in the ATR. Experiment Description for AFC-2A and AFC-2B

    SciTech Connect

    S. L. Hayes; D. J. Utterbeck; T. A. Hyde

    2006-11-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing metallic transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the metallic fuel test series in progress in the ATR. This report documents the experiment description and test matrix of the proposed experiments and the Post Irradiation Examination (PIE) and fabrication schedule.

  10. Fabrication, Inspection, and Test Plan for the Advanced Test Reactor (ATR) High-Power Mixed-Oxide (MOX) Fuel Irradiation Project

    SciTech Connect

    Wachs, G. W.

    1998-09-01

    The Department of Energy (DOE) Fissile Disposition Program (FMDP) has announced that reactor irradiation of Mixed-Oxide (MOX) fuel is one of the preferred alternatives for disposal of surplus weapons-usable plutonium (Pu). MOX fuel has been utilized domestically in test reactors and on an experimental basis in a number of Commercial Light Water Reactors (CLWRs). Most of this experience has been with Pu derived from spent low enriched uranium (LEU) fuel, known as reactor grade (RG) Pu. The High-Power MOX fuel test will be irradiated in the Advanced Test Reactor (ATR) to provide preliminary data to demonstrate that the unique properties of surplus weapons-derived or weapons-grade (WG) plutonium (Pu) do not compromise the applicability of this MOX experience base. The purpose of the high-power experiment, in conjunction with the currently ongoing average-power experiment at the ATR, is to contribute new information concerning the response of WG plutonium under more severe irradiation conditions typical of the peak power locations in commercial reactors. In addition, the high-power test will contribute experience with irradiation of gallium-containing fuel to the database required for resolution of generic CLWR fuel design issues. The distinction between "high-power" and "average-power" relates to the position within the nominal CLWR core. The high-power test project is subject to a number of requirements, as discussed in the Fissile Materials Disposition Program Light Water Reactor Mixed Oxide Fuel Irradiation High-Power Test Project Plan (ORNL/MD/LTR-125).

  11. Evaluation of Corrosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles

    SciTech Connect

    Brower, Jeffrey Owen; Glazoff, Michael Vasily; Eiden, Thomas John; Rezvoi, Aleksey Victor

    2016-08-01

    Advanced Test Reactor (ATR) Cycle 153B-1 was a 14-day, high-power, powered axial locator mechanism (PALM) operating cycle that completed on April 12, 2013. Cycle 153B-1 was a typical operating cycle for the ATR and did not result in any unusual plant transients. ATR was started up and shut down as scheduled. The PALM drive physically moves the selected experiments into and out of the core to simulate reactor startup and heat up, and shutdown and cooldown transients, while the reactor remains in steady state conditions. However, after the cycle was over, several thousand of the flow-assisted corrosion pits and “horseshoeing” defects were readily observable on the surface of the several YA-type fuel elements (these are “dummy” plates that contain no fuel). In order understand these corrosion phenomena a thermal-hydraulic model of coolant channel 20 on a YA-M fuel element was generated. The boundaries of the model were the aluminum EE plate of a YA-M fuel element and a beryllium reflector block with 13 horizontal saw cuts which represented regions of zero flow. The heat generated in fuel plates 1 through 18 was modeled to be passing through the aluminum EE plate. The coolant channel 20 width was set at 0.058 in. (58 mils). It was established that the horizontal saw cuts had a significant effect on the temperature of the coolant. The flow, which was expected to vary linearly with gradual heating of the coolant as it passed through the channel, was extremely turbulent. The temperature rise, which was expected to be a smooth “S” curve, was represented by a series temperature rise “humps,” which occurred at each horizontal saw cut in the beryllium reflector block. Each of the 13 saw cuts had a chamfered edge which resulted in the coolant flow being re-directed as a jet across the coolant channel into the surface of the EE plate, which explained the temperature rise and the observed sscalloping and possibly pitting degradation on the YA-M fuel elements. In

  12. Evaluation of Erosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles

    SciTech Connect

    Brower, Jeffrey O.; Glazoff, Michael V.; Eiden, Thomas J.; Rezvoi, Aleksey V.

    2016-08-01

    Advanced Test Reactor (ATR) Cycle 153B-1 was a 14-day, high-power, powered axial locator mechanism (PALM) operating cycle that completed on April 12, 2013. Cycle 153B-1 was a typical operating cycle for the ATR and did not result in any unusual plant transients. ATR was started up and shut down as scheduled. The PALM drive physically moves the selected experiments into and out of the core to simulate reactor startup and heat up, and shutdown and cooldown transients, while the reactor remains in steady state conditions. However, after the cycle was over, when the fuel elements were removed from the core and inspected, several thousand flow-assisted erosion pits and “horseshoeing” defects were readily observed on the surface of the several YA-type fuel elements (these are aluminum “dummy” plates that contain no fuel). In order to understand these erosion phenomena a thermal-hydraulic model of coolant channel 20 on a YA-M fuel element was generated. The boundaries of the model were the aluminum EE plate of a YA-M fuel element and a beryllium reflector block with 13 horizontal saw cuts which represented regions of zero flow. The heat generated in fuel plates 1 through 18 was modeled to be passing through the aluminum EE plate. The coolant channel 20 width was set at 0.058 in. (58 mils). It was established that the horizontal saw cuts had a significant effect on the temperature of the coolant. The flow, which was expected to vary linearly with gradual heating of the coolant as it passed through the channel, was extremely turbulent. The temperature rise, which was expected to be a smooth “S” curve, was represented by a series temperature rise “humps,” which occurred at each horizontal saw cut in the beryllium reflector block. Each of the 13 saw cuts had a chamfered edge which resulted in the coolant flow being re-directed as a jet across the coolant channel into the surface of the EE plate, which explained the temperature rise and the observed scalloping

  13. Irradiation Planning for Fully-Ceramic Micro-encsapsulated fuel in ATR at LWR-relevant conditions: year-end report on FY-2011

    SciTech Connect

    Abderrafi M. Ougouag; R. Sonat Sen; Michael A. Pope; Brian Boer

    2011-09-01

    This report presents the estimation of required ATR irradiation levels for the DB-FCM fuel design (fueled with Pu and MAs). The fuel and assembly designs are those considered in a companion report [R. S. Sen et al., FCR&D-2011- 00037 or INL/EXT-11-23269]. These results, pertaining to the DB-FCM fuel, are definitive in as much as the design of said fuel is definitive. In addition to the work performed, as required, for DB-FCM fuel, work has started in a preliminary fashion on single-cell UO2 and UN fuels. These latter activities go beyond the original charter of this project and although the corresponding work is incomplete, significant progress has been achieved. However, in this context, all that has been achieved is only preliminary because the corresponding fuel designs are neither finalized nor optimized. In particular, the UO2 case is unlikely to result in a viable fuel design if limited to enrichment at or under 20 weight % in U-235. The UN fuel allows reasonable length cycles and is likely to make an optimal design possible. Despite being limited to preliminary designs and offering only preliminary conclusions, the irradiation planning tasks for UO2 and UN fuels that are summarized in this report are useful to the overall goal of devising and deploying FCM-LWR fuel since the methods acquired and tested in this project and the overall procedure for planning will be available for planning tests for the finalized fuel design. Indeed, once the fuel design is finalized and the expected burnup level is determined, the methodology that has been assembled will allow the prompt finalization of the neutronic planning of the irradiation experiment and would provide guidance on the expected experimental performance of the fuel. Deviations from the expected behavior will then have to be analyzed and the outcome of the analysis may be corrections or modifications for the assessment models as well as, possibly, fuel design modifications, and perhaps even variation of

  14. ATR theory issues

    NASA Astrophysics Data System (ADS)

    Ross, Timothy D.

    2004-09-01

    Issues in ATR Theory emerge by considering three levels of the ATR problem. The term "monolithic architecture (MA)-ATR" is used for problems of standard classification theory. The MA-ATR level has seen recent unification of theories that should be aggressively applied. Modern ATR systems include standard classification theoretic subsystems (e.g., feature extraction, matching, and discrimination); however they also add modeling within a search paradigm. These "aggregate architecture (AA)-ATRs" allow more direct inclusion of application-specific prior (non-sample) knowledge. Greater theoretical support is needed for analyzing AA-ATRs at the system level and integrating the strong MA-ATR theories. The third level of the ATR problem returns to the MA-ATR problem and below. The strongest elements of the MA-ATR theories deal with the stochastic aspects of the ATR problem. Structural aspects of ATRs are an important weak link in the MA-ATR theories. Function decomposition provides an "atom" towards a structural theory. Decomposition provides robustness by constructing the MA-ATR's structure from samples, but is intractable. Standard MA-ATR design is tractable, but is brittle because of an ad hoc structure selection. The key issue in either case is to make explicit use of non-sample (typically structural) knowledge in selecting or, better yet, constructing the MA-ATR's structure.

  15. 78 FR 65183 - Airworthiness Directives; ATR-GIE Avions de Transport Régional Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-31

    ... installing a fuel quantity indicator (FQI) equipped with a locking adaptor on the electrical connector. We... indicator, need to be taken. Although it is recognised that the fuel (indicating) system of the ATR 42/72... mitigated by making installation of an ATR 42 Fuel Quantity Indicator (FQI) on an ATR 72...

  16. ATR performance modeling concepts

    NASA Astrophysics Data System (ADS)

    Ross, Timothy D.; Baker, Hyatt B.; Nolan, Adam R.; McGinnis, Ryan E.; Paulson, Christopher R.

    2016-05-01

    Performance models are needed for automatic target recognition (ATR) development and use. ATRs consume sensor data and produce decisions about the scene observed. ATR performance models (APMs) on the other hand consume operating conditions (OCs) and produce probabilities about what the ATR will produce. APMs are needed for many modeling roles of many kinds of ATRs (each with different sensing modality and exploitation functionality combinations); moreover, there are different approaches to constructing the APMs. Therefore, although many APMs have been developed, there is rarely one that fits a particular need. Clarified APM concepts may allow us to recognize new uses of existing APMs and identify new APM technologies and components that better support coverage of the needed APMs. The concepts begin with thinking of ATRs as mapping OCs of the real scene (including the sensor data) to reports. An APM is then a mapping from explicit quantized OCs (represented with less resolution than the real OCs) and latent OC distributions to report distributions. The roles of APMs can be distinguished by the explicit OCs they consume. APMs used in simulations consume the true state that the ATR is attempting to report. APMs used online with the exploitation consume the sensor signal and derivatives, such as match scores. APMs used in sensor management consume neither of those, but estimate performance from other OCs. This paper will summarize the major building blocks for APMs, including knowledge sources, OC models, look-up tables, analytical and learned mappings, and tools for signal synthesis and exploitation.

  17. ATR neutron spectral characterization

    SciTech Connect

    Rogers, J.W.; Anderl, R.A.

    1995-11-01

    The Advanced Test Reactor (ATR) at INEL provides intense neutron fields for irradiation-effects testing of reactor material samples, for production of radionuclides used in industrial and medical applications, and for scientific research. Characterization of the neutron environments in the irradiation locations of the ATR has been done by means of neutronics calculations and by means of neutron dosimetry based on the use of neutron activation monitors that are placed in the various irradiation locations. The primary purpose of this report is to present the results of an extensive characterization of several ATR irradiation locations based on neutron dosimetry measurements and on least-squares-adjustment analyses that utilize both neutron dosimetry measurements and neutronics calculations. This report builds upon the previous publications, especially the reference 4 paper. Section 2 provides a brief description of the ATR and it tabulates neutron spectral information for typical irradiation locations, as derived from the more historical neutron dosimetry measurements. Relevant details that pertain to the multigroup neutron spectral characterization are covered in section 3. This discussion includes a presentation on the dosimeter irradiation and analyses and a development of the least-squares adjustment methodology, along with a summary of the results of these analyses. Spectrum-averaged cross sections for neutron monitoring and for displacement-damage prediction in Fe, Cr, and Ni are given in section 4. In addition, section4 includes estimates of damage generation rates for these materials in selected ATR irradiation locations. In section 5, the authors present a brief discussion of the most significant conclusions of this work and comment on its relevance to the present ATR core configuration. Finally, detailed numerical and graphical results for the spectrum-characterization analyses in each irradiation location are provided in the Appendix.

  18. ATR Power Supplies

    SciTech Connect

    Bruno, Don

    1996-09-10

    The ATR (AGS to RHIC Transfer Line) is fed beam from two synchrotron rings. The first synchrotron ring is the Booster which receives protons from a 200MeV Linac and can achieve a proton energy of 1.5GeV. The Booster can also receive heavy ions from a 15.5MV Tandem Van de Graaff. The Booster is about 1/8 of a mile in circumference. The Booser then Feeds the AGS (Alternating Gradient Synchrotron) wich can achieve a proton energy of 29.5 Gev. The AGS is about 1/2 of a mile in circumference. The AGS then kicks the beam out to the ATR line which will eventually feed RHIC (Relativistic Heavy Ion Collider) beam starting with the sextant test in December of 1996. The ATR line is about 1/2 mile long. The ATR line is made up of the upgraded U-line, new W, X and Y lines (see Figure 1). The test in November and December of 1995 transported beam from the AGS to the end of the W-line into a beam stop. During the normal operation of RHIC there will be a switching magnet at the end of the W-line which will bend beam into the X-Line and then into the Y-line so that the two beams in RHIC will be rotating in opposite directions.

  19. PUREX new substation ATR

    SciTech Connect

    Nelson, D.E.

    1997-05-12

    This document is the acceptance test report (ATR) for the New PUREX Main and Minisubstations. It covers the factory and vendor acceptance and commissioning test reports. Reports are presented for the Main 5 kV substation building, the building fire system, switchgear, and vacuum breaker; the minisubstation control building and switch gear; commissioning test; electrical system and loads inspection; electrical utilities transformer and cable; and relay setting changes based on operational experience.

  20. Multiple Irradiation Capsule Experiment (MICE)-3B Irradiation Test of Space Fuel Specimens in the Advanced Test Reactor (ATR) - Close Out Documentation for Naval Reactors (NR) Information

    SciTech Connect

    M. Chen; CM Regan; D. Noe

    2006-01-09

    Few data exist for UO{sub 2} or UN within the notional design space for the Prometheus-1 reactor (low fission rate, high temperature, long duration). As such, basic testing is required to validate predictions (and in some cases determine) performance aspects of these fuels. Therefore, the MICE-3B test of UO{sub 2} pellets was designed to provide data on gas release, unrestrained swelling, and restrained swelling at the upper range of fission rates expected for a space reactor. These data would be compared with model predictions and used to determine adequacy of a space reactor design basis relative to fission gas release and swelling of UO{sub 2} fuel and to assess potential pellet-clad interactions. A primary goal of an irradiation test for UN fuel was to assess performance issues currently associated with this fuel type such as gas release, swelling and transient performance. Information learned from this effort may have enabled use of UN fuel for future applications.

  1. Fabrication Report for the AFC-2A and AFC-2B Capsule Irradiations in the ATR

    SciTech Connect

    Timothy A. Hyde

    2007-10-01

    This document provides a general narrative description of the AFC-2A and 2B fuel fabrication processes for the AFC 2A and AFC 2B fuel irradiation experiments fabricated at the Idaho National Laboratory’s Materials and Fuels Complex (MFC) for irradiation in the Advanced Test Reactor (ATR).

  2. Design study for MOX fuel rod scanner for ATR fuel fabrication. Phase I: Design of active neutron scanner. Phase II: Design of passive neutron scanner. Phase III: Design of passive gamma-ray scanner

    SciTech Connect

    Griffith, G.W.; Menlove, H.O.

    1997-09-01

    An active neutron fuel-rod scanner has been designed for the assay of fissile materials in mixed oxide fuel rods. A {sup 252}Cf source is located at the center of the scanner very near the through-hole for the fuel rods. Spontaneous fission neutrons from the californium are moderated and induce fissions within the passing fuel rod. The rod continues past a combined gamma-ray and neutron shield where delayed gamma rays above 1 MeV are detected. The authors used the Monte Carlo neutron-photon (MCNP) code to design the scanner and review optimum materials and geometries. Applications of the rod scanner include accountability of fissile material for safeguards applications, quality control of the fissile content in a fuel rod, and the verification of reactivity potential for mixed oxide fuels. A passive neutron fuel-rod scanner has been designed for the assay of the plutonium in mixed oxide fuel rods. The {sup 240}Pu-effective is measured by counting the spontaneous fission neutrons using a high-efficiency thermal-neutron detector. This passive neutron detector would be combined with a high-resolution gamma-ray system (HRGS) measurement to obtain the total plutonium from the plutonium isotopic ratios. A passive gamma-ray scanner has been designed for the measurement of the {sup 241}Am and plutonium uniformity in mixed oxide fuel rods. The passive gamma-ray emissions from {sup 241}Am (60 keV) and plutonium (150-400 keV) are used to verify the unformity of the fuel enrichment zones and to check for any pellets that are out of specification. The fuel rod is moved through the interior of an NaI(Tl) or a bismuth germanate detector to measure the passive gamma-ray emissions. A tungsten sleeve collimator is used in the through-hole to improve the pellet-to-pellet spatial resolution. The same detector is used to verify the plutonium uniformity in the pellets with a 13-mm tungsten collimator. The low-resolution passive gamma system would be used in the unattended mode.

  3. LWRS ATR Irradiation Testing Readiness Status

    SciTech Connect

    Kristine Barrett

    2012-09-01

    The Light Water Reactor Sustainability (LWRS) Program was established by the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors. The LWRS Program is divided into four R&D Pathways: (1) Materials Aging and Degradation; (2) Advanced Light Water Reactor Nuclear Fuels; (3) Advanced Instrumentation, Information and Control Systems; and (4) Risk-Informed Safety Margin Characterization. This report describes an irradiation testing readiness analysis in preparation of LWRS experiments for irradiation testing at the Idaho National Laboratory (INL) Advanced Test Reactor (ATR) under Pathway (2). The focus of the Advanced LWR Nuclear Fuels Pathway is to improve the scientific knowledge basis for understanding and predicting fundamental performance of advanced nuclear fuel and cladding in nuclear power plants during both nominal and off-nominal conditions. This information will be applied in the design and development of high-performance, high burn-up fuels with improved safety, cladding integrity, and improved nuclear fuel cycle economics

  4. An informative confidence metric for ATR.

    SciTech Connect

    Bow, Wallace Johnston Jr.; Richards, John Alfred; Bray, Brian Kenworthy

    2003-03-01

    Automatic or assisted target recognition (ATR) is an important application of synthetic aperture radar (SAR). Most ATR researchers have focused on the core problem of declaration-that is, detection and identification of targets of interest within a SAR image. For ATR declarations to be of maximum value to an image analyst, however, it is essential that each declaration be accompanied by a reliability estimate or confidence metric. Unfortunately, the need for a clear and informative confidence metric for ATR has generally been overlooked or ignored. We propose a framework and methodology for evaluating the confidence in an ATR system's declarations and competing target hypotheses. Our proposed confidence metric is intuitive, informative, and applicable to a broad class of ATRs. We demonstrate that seemingly similar ATRs may differ fundamentally in the ability-or inability-to identify targets with high confidence.

  5. ATR Performance Estimation Seed Program

    DTIC Science & Technology

    2015-09-28

    for this collec ion of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data ...sources, gathering and maintaining the data needed, and completing and reviewing the collec ion of information. Send comments regarding this burden...to produce simulated MCM sonar data and demonstrate the impact of system, environmental, and target scattering effects on ATR detection

  6. Validation of HELIOS for ATR Core Follow Analyses

    SciTech Connect

    Bays, Samuel E.; Swain, Emily T.; Crawford, Douglas S.; Nigg, David W.

    2015-03-01

    This work summarizes the validation analyses for the HELIOS code to support core design and safety assurance calculations of the Advanced Test Reactor (ATR). Past and current core safety assurance is performed by the PDQ-7 diffusion code; a state of the art reactor physics simulation tool from the nuclear industry’s earlier days. Over the past twenty years, improvements in computational speed have enabled the use of modern neutron transport methodologies to replace the role of diffusion theory for simulation of complex systems, such as the ATR. More exact methodologies have enabled a paradigm-shift away from highly tuned codes that force compliance with a bounding safety envelope, and towards codes regularly validated against routine measurements. To validate HELIOS, the 16 ATR operational cycles from late-2009 to present were modeled. The computed power distribution was compared against data collected by the ATR’s on-line power surveillance system. It was found that the ATR’s lobe-powers could be determined with ±10% accuracy. Also, the ATR’s cold startup shim configuration for each of these 16 cycles was estimated and compared against the reported critical position from the reactor log-book. HELIOS successfully predicted criticality within the tolerance set by the ATR startup procedure for 13 out of the 16 cycles. This is compared to 12 times for PDQ (without empirical adjustment). These findings, as well as other insights discussed in this report, suggest that HELIOS is highly suited for replacing PDQ for core safety assurance of the ATR. Furthermore, a modern verification and validation framework has been established that allows reactor and fuel performance data to be computed with a known degree of accuracy and stated uncertainty.

  7. AGR-2 Data Qualification Report for ATR Cycle 154B

    SciTech Connect

    Binh Pham; Jeff Einerson

    2014-01-01

    This report provides the data qualification status of Advanced Gas Reactor-2 (AGR-2) fuel irradiation experimental data from Advanced Test Reactor (ATR) Cycle 154B as recorded in the Nuclear Data Management and Analysis System (NDMAS). This is the last cycle of AGR-2 irradiation, as the test train was pulled from the ATR core during the outage portion of ATR Cycle 155A. The AGR-2 data streams addressed in this report include thermocouple (TC) temperatures, sweep gas data (flow rates including new Fission Product Monitoring (FPM) downstream flows from Fission Product Monitoring System (FPMS) detectors, pressure, and moisture content), and FPMS data (release rates and release-to-birth rate ratios [R/Bs]) for each of the six capsules in the AGR-2 experiment. The final data qualification status for these data streams is determined by a Data Review Committee (DRC) comprised of AGR technical leads, Sitewide Quality Assurance (QA), and NDMAS analysts. The Data Review Committee reviewed the data acquisition process, considered whether the data met the requirements for data collection as specified in QA-approved Very High Temperature Reactor (VHTR) data collection plans, examined the results of NDMAS data testing and statistical analyses, and confirmed the qualification status of the data as given in this report.

  8. Fuel processing device

    DOEpatents

    Ahluwalia, Rajesh K.; Ahmed, Shabbir; Lee, Sheldon H. D.

    2011-08-02

    An improved fuel processor for fuel cells is provided whereby the startup time of the processor is less than sixty seconds and can be as low as 30 seconds, if not less. A rapid startup time is achieved by either igniting or allowing a small mixture of air and fuel to react over and warm up the catalyst of an autothermal reformer (ATR). The ATR then produces combustible gases to be subsequently oxidized on and simultaneously warm up water-gas shift zone catalysts. After normal operating temperature has been achieved, the proportion of air included with the fuel is greatly diminished.

  9. Shadow-based SAR ATR performance prediction

    NASA Astrophysics Data System (ADS)

    Blacknell, D.

    2009-05-01

    The ability to assess potential automatic target recognition (ATR) performance for a given SAR system, target set and clutter environment is a key requirement for system procurement and mission planning. A cost-effective solution is to develop a theoretical model which can provide ATR performance predictions given a parameterisation of the system, targets and environment. In this paper, a classification scheme based on shadow information is analysed. Consideration of the statistical accuracy of shadow-based features allows ATR performance to be predicted. Quantitative comparisons of predicted performance with results obtained via simulation as well as against real data from the MSTAR data set are presented. It is seen that a reasonable level of agreement is obtained which gives confidence in extending the theoretical concepts to more complex feature-based ATR schemes.

  10. ATR2000 Mercury/MPI Real-Time ATR System User's Guide

    SciTech Connect

    Meyer, R.H.; Doerfler, D.W.

    2000-12-01

    The Air Force's Electronic Systems Center has funded Sandia National Laboratories to develop an Automatic Target Recognition (ATR) System for the Air Force's Joint STARS platform using Mercury Computer systems hardware. This report provides general theory on the internal operations of the Real-Time ATR system and provides some basic techniques that can be used to reconfigure the system and monitor its runtime operation. In addition, general information on how to interface an image formation processor and a human machine interface to the ATR is provided. This report is not meant to be a tutorial on the ATR algorithms.

  11. SAR ATR using genetics based machine learning

    NASA Astrophysics Data System (ADS)

    Ravichandran, B.; Gandhe, Avinash; Smith, Robert; Mehra, Raman

    2005-05-01

    Addressing the challenge of robust ATR, this paper describes the development and demonstration of Machine Learning for Robust ATR. The primary innovation of this work is the development of an automated way of developing heuristic inference rules that can draw on multiple models and multiple feature types to make more robust ATR decisions. The key realization is that this meta learning problem is one of structural learning; that can be conducted independently of parameter learning associated with each model and feature based technique, and more effectively draw on the strengths of all such techniques, and even information from unforeseen techniques. This is accomplished by using robust, genetics-based machine learning for the ill conditioned combinatorial problem of structural rule learning, while using statistical and mathematical techniques for parameter learning. This paper describes a learning classifier system approach (with evolutionary computation for structural learning) for robust ATR and points to a promising solution to the structural learning problem, across multiple feature types (which we will refer to as the meta-learning problem), for ATR with EOCs. This system was tested on MSTAR Public Release SAR data using nominal and extended operation conditions. These results were also compared against two baseline classifiers, a PCA based distance classifier and a MSE classifier. The systems were evaluated for accuracy (via training set classification) and robustness (via testing set classification). In both cases, the LCS based robust ATR system performed very well with accuracy over 99% and robustness over 80%.

  12. Monte-Carlo Code (MCNP) Modeling of the Advanced Test Reactor Applicable to the Mixed Oxide (MOX) Test Irradiation

    SciTech Connect

    G. S. Chang; R. C. Pederson

    2005-07-01

    Mixed oxide (MOX) test capsules prepared with weapons-derived plutonium have been irradiated to a burnup of 50 GWd/t. The MOX fuel was fabricated at Los Alamos National Laboratory by a master-mix process and has been irradiated in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). Previous withdrawals of the same fuel have occurred at 9, 21, 30, and 40 GWd/t. Oak Ridge National Laboratory (ORNL) manages this test series for the Department of Energy’s Fissile Materials Disposition Program (FMDP). The fuel burnup analyses presented in this study were performed using MCWO, a welldeveloped tool that couples the Monte Carlo transport code MCNP with the isotope depletion and buildup code ORIGEN-2. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations for the ATR small I-irradiation test position. The purpose of this report is to validate both the Weapons-Grade Mixed Oxide (WG-MOX) test assembly model and the new fuel burnup analysis methodology by comparing the computed results against the neutron monitor measurements.

  13. Neutron spectrum studies in the ATR (Advanced Test Reactor)

    SciTech Connect

    Rogers, J.W.; Anderl, R.A.; Putnam, M.H.

    1990-01-01

    The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL) has been and currently is used to provide irradiation fields to study the effects of intense radiation on samples of reactor materials. These samples include fuel, cladding, control and structural materials. The ATR is also used to irradiate target materials for the production of radionuclides used in industrial and medical applications as well as for scientific research. Routine monitoring of the thermal'' and fast'' neutron levels have been conducted during every operational cycle since its startup in 1970. The routine neutron dosimetry has been primarily accomplished using the {sup 59}Co(n,{gamma}){sup 60}Co reaction for thermal'' neutrons and the {sup 58}Ni(n,p) {sup 58}Co reaction for fast'' neutrons as described in ASTM standard methods E261, E262, and E264. Neutron spectrum studies have now been conducted in the epithermal and fast neutron energy ranges for the various capsule irradiation test facilities and the routine neutron monitoring locations. 7 refs., 5 figs., 1 tab.

  14. A perspective on ATR evaluation technology

    NASA Astrophysics Data System (ADS)

    Sadjadi, Firooz; Bazakos, Mike

    1990-09-01

    A historical perspective on the evolution of performance evaluation technology for automatic target recognition (ATR) systems is presented. It is shown that the ad hoc and artistic evaluation techniques of the past are now evolving into scientific approaches. The most perspective areas of this technology include: (1) first principle coupled, multi-sensor modeling of objects, environment, atmosphere, and vegetation; (2) integration of models with the task of ATR algorithm development; (3) integration of a new generation of parallel processor that can process every pixel of an image without the need for data reduction; (4) extending the instrumentation control of ATR to include sensor selection and sensor fusion; and (5) development of signal metrics for radar, acoustic and ladar, and linking these metrics to phenomenological sources.

  15. Cascaded automatic target recognition (Cascaded ATR)

    NASA Astrophysics Data System (ADS)

    Walls, Bradley

    2010-04-01

    The global war on terror has plunged US and coalition forces into a battle space requiring the continuous adaptation of tactics and technologies to cope with an elusive enemy. As a result, technologies that enhance the intelligence, surveillance, and reconnaissance (ISR) mission making the warfighter more effective are experiencing increased interest. In this paper we show how a new generation of smart cameras built around foveated sensing makes possible a powerful ISR technique termed Cascaded ATR. Foveated sensing is an innovative optical concept in which a single aperture captures two distinct fields of view. In Cascaded ATR, foveated sensing is used to provide a coarse resolution, persistent surveillance, wide field of view (WFOV) detector to accomplish detection level perception. At the same time, within the foveated sensor, these detection locations are passed as a cue to a steerable, high fidelity, narrow field of view (NFOV) detector to perform recognition level perception. Two new ISR mission scenarios, utilizing Cascaded ATR, are proposed.

  16. ATR LEU Monothlic and Dispersed with 10B Loading Minimization Design – Neutronics Performance Analysis

    SciTech Connect

    G. S. Chang

    2001-10-01

    The Advanced Test Reactor (ATR), currently operating in the United States, is used for material testing at very high neutron fluxes. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting HEU driven reactor cores to low-enriched uranium (LEU) cores. The present work investigates the optimized LEU Monolithic and Dispersed fuel with 10B loading minimization design and evaluates the subsequent neutronics operating effects of these optimized fuel designs. The MCNP ATR 1/8th core model was used to optimize the 235U and minimize the 10B loading in the LEU core, such that the differences in K-eff and heat flux profiles between the HEU and LEU cores were minimized. The fuel depletion methodology MCWO was used to calculate K eff versus effective full power days (EFPD) in this paper. The MCWO-calculated results for the optimized LEU Monolithic and Dispersed fuel cases demonstrated adequate excess reactivity such that the K-eff versus EFPD plot is similar to the ATR reference HEU case study. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm (20 mil). In this work, the proposed LEU Monolithic (U-10Mo) core conversion case with nominal fuel meat thickness of 0.330 mm (13 mil) and 235U enrichment of 19.7 wt% is used to optimize the radial heat flux profile by varying the fuel meat thickness. The proposed LEU fuel meat varies from 0.203 mm (8.0 mil) to 0.254 mm (10.0 mil) at the inner four fuel plates (1-4) and outer four fuel plates (16-19). In addition, an optimized LEU dispersed (U7Mo) case with all the fuel meat thickness of 0.635 mm (25 mil) was also proposed. Then, for both Monolithic and dispersed cases, a burnable absorber – 10B, was added in the inner and outer plates to reduce the initial excess reactivity, and the higher to average ratio of the inner

  17. Hardening Neutron Spectrum for Advanced Actinides Transmutation Experiments in the ATR

    SciTech Connect

    G. S. Chang; R. G. Ambrosek

    2004-05-01

    The most effective method for transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products is in a fast neutron spectrum reactor. In the absence of a fast rest reactor in the United States, initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. Such a test facility, with a spectrum similar but somewhat softer than that of the liquid-metal fast breeder reactor (LMFBR), has been constructed in the INEEL's Advanced Test Reactor (ATR). The radial fission power distribution of the actinide fuel pin, which is an important parameter in fission gas released modelling, needs to be accurately predicted and the hardened neturon spectrum in the ATR and the LMFBR fast neutron spectrum is compared. The comparison analyses in this study are peformed using MCWO, a well-developed tool that couples the Monte Carlo transport code MCNP with the isotope depletion and build-up code ORIGEN-2. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations and detailed radial fission power profile calculations for a typical fast reactor (LMFBR) neutron spectrum and the hardened neturon spectrum test region in the ATR. The MCWO-calculated results indicate that the cadmium basket used in the advanced fuel test assembly in the ATR can effectively depress the linear heat generation rate in the experimental fuels and harden the neutron spectrum in the test region.

  18. Hardening neutron spectrum for advanced actinide transmutation experiments in the ATR.

    PubMed

    Chang, G S; Ambrosek, R G

    2005-01-01

    The most effective method for transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products is in a fast neutron spectrum reactor. In the absence of a fast test reactor in the United States, initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. Such a test facility, with a spectrum similar but somewhat softer than that of the liquid-metal fast breeder reactor (LMFBR), has been constructed in the INEEL's Advanced Test Reactor (ATR). The radial fission power distribution of the actinide fuel pin, which is an important parameter in fission gas release modelling, needs to be accurately predicted and the hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum is compared. The comparison analyses in this study are performed using MCWO, a well-developed tool that couples the Monte Carlo transport code MCNP with the isotope depletion and build-up code ORIGEN-2. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations and detailed radial fission power profile calculations for a typical fast reactor (LMFBR) neutron spectrum and the hardened neutron spectrum test region in the ATR. The MCWO-calculated results indicate that the cadmium basket used in the advanced fuel test assembly in the ATR can effectively depress the linear heat generation rate in the experimental fuels and harden the neutron spectrum in the test region.

  19. Vanadium irradiation at ATR - neutronics aspects

    SciTech Connect

    Gomes, I.C.; Smith, D.L.

    1995-04-01

    Calculations were performed to estimate damage and transmutation rates in vanadium irradiated in the ATR (Advanced Test Reactor) located in Idaho. The main focuses of the study are to evaluate the transmutation of vanadium to chromium and to explore ways to design the irradiation experiment to avoid excessive transmutation. It was found that the A-hole of ATR produces damage rate of {approximately} 0.2%/dpa of vanadium to chromium. A thermal neutron filter can be incorporated into the design to reduce the vanadium-to-chromium transmutation rate to low levels. A filter 1-2 mm thick of gadolinium or hafnium can be used.

  20. Independent Review of AFC 2A, 2B, and 2E ATR Irradiation Tests

    SciTech Connect

    M. Cappiello; R. Hobbins; K. Penny; L. Walters

    2014-01-01

    As part of the Department of Energy Advanced Fuel Cycle program, a series of fuels development irradiation tests have been performed in the Advanced Test Reactor (ATR) at the Idaho National Laboratory. These tests are providing excellent data for advanced fuels development. The program is focused on the transmutation of higher actinides which best can be accomplished in a sodium-cooled fast reactor. Because a fast test reactor is no longer available in the US, a special test vehicle is used to achieve near-prototypic fast reactor conditions (neutron spectra and temperature) for use in ATR (a water-cooled thermal reactor). As part of the testing program, there were many successful tests of advanced fuels including metals and ceramics. Recently however, there have been three experimental campaigns using metal fuels that experienced failure during irradiation. At the request of the program, an independent review committee was convened to review the post-test analyses performed by the fuels development team, to assess the conclusions of the team for the cause of the failures, to assess the adequacy and completeness of the analyses, to identify issues that were missed, and to make recommendations for improvements in the design and operation of future tests. Although there is some difference of opinion, the review committee largely agreed with the conclusions of the fuel development team regarding the cause of the failures. For the most part, the analyses that support the conclusions are sufficient.

  1. Focusing and matching properties of the ATR transfer line

    SciTech Connect

    Tsoupas, N.; Fischer, W.; Kewisch, J.; MacKay, W.W.; Peggs, S.; Pilat, F.; Tepikian, S.; Wei, J.

    1997-07-01

    The AGS to RHIC (AtR) beam transfer line has been constructed and will be used to transfer beam bunches from the AGS machine into the RHIC machine which is presently under construction at BNL. The original design of the AtR line has been modified. This article will present the optics of the various sections of the existing AtR beam line, as well as the matching capabilities of the AtR line to the RHIC machine.

  2. Overview of the ATR Power Supplies

    NASA Astrophysics Data System (ADS)

    Bruno, D.; Soukas, A.; Toldo, F.; Lambiase, B.

    1997-05-01

    The AGS to RHIC transfer Line (ATR) transports a variety of beams from the Alternating Gradient Synchrotron (AGS) which gets its input from the Booster Synchrotron. In turn, the Booster receives input beams from either a Tandem Van de Graaff (heavy ions) or a Linac(protons). The AGS extracts beam bunches, up to a rate of 30 Hertz, to the ATR which will eventually feed the Relativistic Heavy Ion Collider (RHIC) starting with the sextant test in January of 1996. The ATR is made up of the upgraded U line and the new W, X and Y lines. A test in 1995 transported beam to the end of the W line. During normal operation, a pulsed switching magnet at the end of the W line will bend the beam into the X line or the Y line so that the two rings in RHIC are filled with counter rotating beams. The ATR line is comprised of 80 power supplies (PS's), 17 of which are upgraded AGS PS's. The remaining 63 PS's were newly purchased. These PS's range from bipolar 600 watt linear type trim magnet PS's to 1 Megawatt, thyristor, dipole PS's. Results of the commissioning runs will be presented, as well as descriptions of regulation, filtering, and analog and digital controls.

  3. Overview of the ATR power supplies

    SciTech Connect

    Bruno, D.; Soukas, A.; Toldo, F.; Lambiase, R.F.

    1997-07-01

    The AGS to RHIC transfer line (ATR) transports a variety of beams from the Alternating Gradient Synchrotron (AGS) which gets its input from the Booster Synchrotron. In turn, the Booster receives input beams from either a Tandem Van de Graaff (heavy ions) or a Linac (protons). The AGS extracts beam bunches, up to a rate of 30 Hertz, to the ATR which feeds the Relativistic Heavy Ion Collider (RHIC) starting with the sextant test in January of 1997. The ATR is made up of the upgraded U line and the new W, X, and Y lines. A test in 1995 transported beam to the end of the W line. During normal operation, a pulsed switching magnet at the end of the W line will bend the beam into the X line or the Y line so that the two storage rings in RHIC are filled with counter rotating beams. The ATR line is comprised of 80 power supplies (PS`s), 17 of which are upgraded AGS PS`s. The remaining 63 PS`s were newly purchased. These PS`s range from bipolar 600 watt linear type trim magnet PS`s to 1 Megawatt, thyristor, dipole PS`s. Results of the commissioning runs will be presented, as well as descriptions of regulation, filtering, and analog and digital controls.

  4. MOX and MOX with 237Np/241Am Inert Fission Gas Generation Comparison in ATR

    SciTech Connect

    G. S. Chang; M. Robel; W. J. Carmack; D. J. Utterbeck

    2006-06-01

    The treatment of spent fuel produced in nuclear power generation is one of the most important issues to both the nuclear community and the general public. One of the viable options to long-term geological disposal of spent fuel is to extract plutonium, minor actinides (MA), and potentially long-lived fission products from the spent fuel and transmute them into short-lived or stable radionuclides in currently operating light-water reactors (LWR), thus reducing the radiological toxicity of the nuclear waste stream. One of the challenges is to demonstrate that the burnup-dependent characteristic differences between Reactor-Grade Mixed Oxide (RG-MOX) fuel and RG-MOX fuel with MA Np-237 and Am 241 are minimal, particularly, the inert gas generation rate, such that the commercial MOX fuel experience base is applicable. Under the Advanced Fuel Cycle Initiative (AFCI), developmental fuel specimens in experimental assembly LWR-2 are being tested in the northwest (NW) I-24 irradiation position of the Advanced Test Reactor (ATR). The experiment uses MOX fuel test hardware, and contains capsules with MOX fuel consisting of mixed oxide manufactured fuel using reactor grade plutonium (RG-Pu) and mixed oxide manufactured fuel using RG-Pu with added Np/Am. This study will compare the fuel neutronics depletion characteristics of Case-1 RG-MOX and Case-2 RG-MOX with Np/Am.

  5. MIR-ATR sensor for process monitoring

    NASA Astrophysics Data System (ADS)

    Geörg, Daniel; Schalk, Robert; Methner, Frank-Jürgen; Beuermann, Thomas

    2015-06-01

    A mid-infrared attenuated total reflectance (MIR-ATR) sensor has been developed for chemical reaction monitoring. The optical setup of the compact and low-priced sensor consists of an IR emitter as light source, a zinc selenide (ZnSe) ATR prism as boundary to the process, and four thermopile detectors, each equipped with an optical bandpass filter. The practical applicability was tested during esterification of ethanol and formic acid to ethyl formate and water as a model reaction with subsequent distillation. For reference analysis, a Fourier transform mid-infrared (FT-MIR) spectrometer with diamond ATR module was applied. On-line measurements using the MIR-ATR sensor and the FT-MIR spectrometer were performed in a bypass loop. The sensor was calibrated by multiple linear regression in order to link the measured absorbance in the four optical channels to the analyte concentrations. The analytical potential of the MIR-ATR sensor was demonstrated by simultaneous real-time monitoring of all four chemical substances involved in the esterification and distillation process. The temporal courses of the sensor signals are in accordance with the concentration values achieved by the commercial FT-MIR spectrometer. The standard error of prediction for ethanol, formic acid, ethyl formate, and water were 0.38 mol L  -  1, 0.48 mol L  -  1, 0.38 mol L  -  1, and 1.12 mol L  -  1, respectively. A procedure based on MIR spectra is presented to simulate the response characteristics of the sensor if the transmission ranges of the filters are varied. Using this tool analyte specific bandpass filters for a particular chemical reaction can be identified. By exchanging the optical filters, the sensor can be adapted to a wide range of processes in the chemical, pharmaceutical, and beverage industries.

  6. Submission of FeCrAl Feedstock for Support of AFC ATR-2 Irradiations

    SciTech Connect

    Field, Kevin G.; Barrett, Kristine E.; Sun, Zhiqian; Yamamoto, Yukinori

    2016-09-16

    The Advanced Test Reactor (ATR) is currently being used to test accident tolerant fuel (ATF) forms destined for commercial nuclear power plant deployment. One irradiation program using the ATR for ATF concepts, Accident Tolerant Fuel-2 (ATF-2), is a water loop irradiation test using miniaturized fuel pins as test articles. This complicated testing configuration requires a series of pre-test experiments and verification including a flowing loop autoclave test and a sensor qualification test (SQT) prior to full test train deployment within the ATR. In support of the ATF-2 irradiation program, Oak Ridge National Laboratory (ORNL) has supplied two different Generation II FeCrAl alloys in rod stock form to Idaho National Laboratory (INL). These rods will be machined into dummy pins for deployment in the autoclave test and SQT. Post-test analysis of the dummy pins will provide initial insight into the performance of Generation II FeCrAl alloys in the ATF-2 irradiation experiment as well as within a commercial nuclear reactor.

  7. The distribution of atrazine (ATR) and ATR metabolites in the Wistar rat following gestational/lactational exposures

    EPA Science Inventory

    Gestational/lactational exposure to ATR is reported to alter reproductive/developmental function, yet our understanding of the transfer of ATR and/or its metabolites from the dam to the fetus/offspring is limited. Previously we examined the lactational transfer of CI4-ATR, but sp...

  8. The distribution of atrazine (ATR) and ATR metabolites in the Wistar rat following gestational/lactational exposures

    EPA Science Inventory

    Gestational/lactational exposure to ATR is reported to alter reproductive/developmental function, yet our understanding of the transfer of ATR and/or its metabolites from the dam to the fetus/offspring is limited. Previously we examined the lactational transfer of CI4-ATR, but sp...

  9. AGR-3/4 Final Data Qualification Report for ATR Cycles 151A through 155B-1

    SciTech Connect

    Pham, Binh T.

    2015-03-01

    This report provides the qualification status of experimental data for the entire Advanced Gas Reactor 3/4 (AGR 3/4) fuel irradiation. AGR-3/4 is the third in a series of planned irradiation experiments conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for the AGR Fuel Development and Qualification Program, which supports development of the advanced reactor technology under the INL ART Technology Development Office (TDO). The main objective of AGR-3/4 irradiation is to provide a known source of fission products for subsequent transport through compact matrix and structural graphite materials due to the presence of designed-to-fail fuel particles. Full power irradiation of the AGR 3/4 test began on December 14, 2011 (ATR Cycle 151A), and was completed on April 12, 2014 (end of ATR Cycle 155B) after 369.1 effective full power days of irradiation. The AGR-3/4 test was in the reactor core for eight of the ten ATR cycles between 151A and 155B. During the unplanned outage cycle, 153A, the experiment was removed from the ATR northeast flux trap (NEFT) location and stored in the ATR canal. This was to prevent overheating of fuel compacts due to higher than normal ATR power during the subsequent Powered Axial Locator Mechanism cycle, 153B. The AGR 3/4 test was inserted back into the ATR NEFT location during the outage of ATR Cycle 154A on April 26, 2013. Therefore, the AGR-3/4 irradiation data received during these 2 cycles (153A and 153B) are irrelevant and their qualification status isnot included in this report. Additionally, during ATR Cycle 152A the ATR core ran at low power for a short enough duration that the irradiation data are not used for physics and thermal calculations. However, the qualification status of irradiation data for this cycle is still covered in this report. As a result, this report includes data from 8 ATR Cycles: 151A, 151B, 152A, 152B, 154A, 154B, 155A, and 155B, as recorded in the Nuclear Data Management and

  10. A Simplified Shuttle Irradiation Facility for ATR

    SciTech Connect

    A. J. Palmer; S. T. Laflin

    1999-08-01

    During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple "low cost" shuttle irradiation facility for ATR has been developed. Cost were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4-5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations.

  11. Function of the ATR N-terminal domain revealed by an ATM/ATR chimera

    SciTech Connect

    Chen Xinping; Zhao Runxiang; Glick, Gloria G.; Cortez, David . E-mail: david.cortez@vanderbilt.edu

    2007-05-01

    The ATM and ATR kinases function at the apex of checkpoint signaling pathways. These kinases share significant sequence similarity, phosphorylate many of the same substrates, and have overlapping roles in initiating cell cycle checkpoints. However, they sense DNA damage through distinct mechanisms. ATR primarily senses single stranded DNA (ssDNA) through its interaction with ATRIP, and ATM senses double strand breaks through its interaction with Nbs1. We determined that the N-terminus of ATR contains a domain that binds ATRIP. Attaching this domain to ATM allowed the fusion protein (ATM*) to bind ATRIP and associate with RPA-coated ssDNA. ATM* also gained the ability to localize efficiently to stalled replication forks as well as double strand breaks. Despite having normal kinase activity when tested in vitro and being phosphorylated on S1981 in vivo, ATM* is defective in checkpoint signaling and does not complement cellular deficiencies in either ATM or ATR. These data indicate that the N-terminus of ATR is sufficient to bind ATRIP and to promote localization to sites of replication stress.

  12. ATR promotes cilia signalling: links to developmental impacts

    PubMed Central

    Stiff, Tom; Casar Tena, Teresa; O'Driscoll, Mark; Jeggo, Penny A.; Philipp, Melanie

    2016-01-01

    Mutations in ATR (ataxia telangiectasia and RAD3-related) cause Seckel syndrome (ATR-SS), a microcephalic primordial dwarfism disorder. Hitherto, the clinical manifestation of ATR deficiency has been attributed to its canonical role in DNA damage response signalling following replication fork stalling/collapse. Here, we show that ATR regulates cilia-dependent signalling in a manner that can be uncoupled from its function during replication. ATR-depleted or patient-derived ATR-SS cells form cilia of slightly reduced length but are dramatically impaired in cilia-dependent signalling functions, including growth factor and Sonic hedgehog signalling. To better understand the developmental impact of ATR loss of function, we also used zebrafish as a model. Zebrafish embryos depleted of Atr resembled ATR-SS morphology, showed a modest but statistically significant reduction in cilia length and other morphological features indicative of cilia dysfunction. Additionally, they displayed defects in left-right asymmetry including ambiguous expression of southpaw, incorrectly looped hearts and randomized localization of internal organs including the pancreas, features typically conferred by cilia dysfunction. Our findings reveal a novel role for ATR in cilia signalling distinct from its canonical function during replication and strengthen emerging links between cilia function and development. PMID:26908596

  13. Targeting ATR in DNA damage response and cancer therapeutics.

    PubMed

    Fokas, Emmanouil; Prevo, Remko; Hammond, Ester M; Brunner, Thomas B; McKenna, W Gillies; Muschel, Ruth J

    2014-02-01

    The ataxia telangiectasia and Rad3-related (ATR) plays an important role in maintaining genome integrity during DNA replication through the phosphorylation and activation of Chk1 and regulation of the DNA damage response. Preclinical studies have shown that disruption of ATR pathway can exacerbate the levels of replication stress in oncogene-driven murine tumors to promote cell killing. Additionally, inhibition of ATR can sensitise tumor cells to radiation or chemotherapy. Accumulating evidence suggests that targeting ATR can selectively sensitize cancer cells but not normal cells to DNA damage. Furthermore, in hypoxic conditions, ATR blockade results in overloading replication stress and DNA damage response causing cell death. Despite the attractiveness of ATR inhibition in the treatment of cancer, specific ATR inhibitors have remained elusive. In the last two years however, selective ATR inhibitors suitable for in vitro and - most recently - in vivo studies have been identified. In this article, we will review the literature on ATR function, its role in DDR and the potential of ATR inhibition to enhance the efficacy of radiation and chemotherapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Improved automatic target recognition (ATR) value through enhancements and accommodations

    NASA Astrophysics Data System (ADS)

    Ross, Timothy D.; Goodwon, Lloyd C.

    2006-05-01

    There is a strong and growing need for automatic target recognition (ATR) technologies. Those technologies have made great strides; however, there is a general sense that they are not having the full impact desired. This paper develops a value-based framework for considering how ATR technology can be made more relevant and then introduces and expands on two elements within that framework: 'enhancements' and 'accommodations'. Value is used here as the degree to which a technology's benefits exceed the technology's costs. Value may be improved by increasing benefits or decreasing costs; but it may be as important that the uncertainty about benefits and costs be reduced. Enhancements and accommodations are distinguished here from the 'core ATR'. While it is generally appreciated that improved core ATR performance could improve value, enhancements and accommodations might be overlooked by those focused on ATRs. Enhancements are ways of making the overall system, inclusive of a core ATR, more capable. Accommodations are ways of making the problem easier for the core ATR. An example enhancement is technology to fuse the output of the core ATR with other sources. An example accommodation is for the user to agree to limit the target set to large, and therefore more easily recognized, objects. This paper encourages the consideration of this framework and outlines a number of candidates for enhancements and accommodations for synthetic aperture radar (SAR) ATR, including humans-in-the-loop, change detection, fusion, modeling confusers, group detection, adaptive algorithms, class make-up, and scene-based decisions.

  15. Adaptive configuration and control in an ATR system

    NASA Astrophysics Data System (ADS)

    Roberts, Barry A.; Au, Wing K.

    1995-06-01

    Today's ATR is constructed via inefficient and suboptimal system configuration and training. The process of configuring an ATR is currently very labor intensive, subjective, and inaccurate, as is the process of training an ATR for a particular mission. To cure this deficiency, what is desired is an automated method of configuration and training which is capable of searching the N-dimensional space of modules, algorithms, and parameter values to produce ATR algorithm suites which perform best in each trained scenario. Also, today's ATR is only capable of a limited amount of adaptation to sensed (or otherwise obtained) changes in the environment. To improve the adaptibility of ATR processing and thereby improve accuracy and robustness, what is desired is a high-level control structure which enables system adaptation via changes in parameter values and changes in algorithms (at the component and at the 'suite' level). The Honeywell effort is producing a system for Adaptive Configuration and Control (ACC) of an ATR system which addresses the above described problems. The software system is using the machine learning technique of Genetic Algorithms to autonomously and optimally perform configuration and training and it is using case-based reasoning to provide run-time configuration and control of the ATR system. This paper provides an overview of the ACC system, describes its operation, and describes the benefits it provides to ATR systems.

  16. ATR maintains select progenitors during nervous system development

    PubMed Central

    Lee, Youngsoo; Shull, Erin RP; Frappart, Pierre-Olivier; Katyal, Sachin; Enriquez-Rios, Vanessa; Zhao, Jingfeng; Russell, Helen R; Brown, Eric J; McKinnon, Peter J

    2012-01-01

    The ATR (ATM (ataxia telangiectasia mutated) and rad3-related) checkpoint kinase is considered critical for signalling DNA replication stress and its dysfunction can lead to the neurodevelopmental disorder, ATR-Seckel syndrome. To understand how ATR functions during neurogenesis, we conditionally deleted Atr broadly throughout the murine nervous system, or in a restricted manner in the dorsal telencephalon. Unexpectedly, in both scenarios, Atr loss impacted neurogenesis relatively late during neural development involving only certain progenitor populations. Whereas the Atr-deficient embryonic cerebellar external germinal layer underwent p53- (and p16Ink4a/Arf)-independent proliferation arrest, other brain regions suffered apoptosis that was partially p53 dependent. In contrast to other organs, in the nervous system, p53 loss did not worsen the outcome of Atr inactivation. Coincident inactivation of Atm also did not affect the phenotype after Atr deletion, supporting non-overlapping physiological roles for these related DNA damage-response kinases in the brain. Rather than an essential general role in preventing replication stress, our data indicate that ATR functions to monitor genomic integrity in a selective spatiotemporal manner during neurogenesis. PMID:22266795

  17. A Simplified Shuttle Irradiation Facility for ATR

    SciTech Connect

    Palmer, Alma Joseph; Laflin, S. T.

    1999-09-01

    During the past fifteen years there has been a steady increase in the demand for radioisotopes in nuclear medicine and a corresponding decline in the number of reactors within the U.S. capable of producing them. The Advanced Test Reactor (ATR) is the largest operating test reactor in the U.S., but its isotope production capabilities have been limited by the lack of an installed isotope shuttle irradiation system. A concept for a simple “low cost” shuttle irradiation facility for ATR has been developed. Costs were reduced (in comparison to previous ATR designs) by using a shielded trough of water installed in an occupiable cubicle as a shielding and contamination control barrier for the send and receive station. This shielding concept also allows all control valves to be operated by hand and thus the need for an automatic control system was eliminated. It was determined that 4 – 5 ft of water would be adequate to shield the isotopes of interest while shuttles are transferred to a small carrier. An additional feature of the current design is a non-isolatable by-pass line, which provides a minimum coolant flow to the test region regardless of which control valves are opened or closed. This by-pass line allows the shuttle facility to be operated without bringing reactor coolant water into the cubicle except for send and receive operations. The irradiation position selected for this concept is a 1.5 inch “B” hole (B-11). This position provides neutron fluxes of approximately: 1.6 x 1014 (<0.5 eV) and 4.0 x 1013 (>0.8 MeV) n/cm2*sec.

  18. Utilizing feedback in adaptive SAR ATR systems

    NASA Astrophysics Data System (ADS)

    Horsfield, Owen; Blacknell, David

    2009-05-01

    Existing SAR ATR systems are usually trained off-line with samples of target imagery or CAD models, prior to conducting a mission. If the training data is not representative of mission conditions, then poor performance may result. In addition, it is difficult to acquire suitable training data for the many target types of interest. The Adaptive SAR ATR Problem Set (AdaptSAPS) program provides a MATLAB framework and image database for developing systems that adapt to mission conditions, meaning less reliance on accurate training data. A key function of an adaptive system is the ability to utilise truth feedback to improve performance, and it is this feature which AdaptSAPS is intended to exploit. This paper presents a new method for SAR ATR that does not use training data, based on supervised learning. This is achieved by using feature-based classification, and several new shadow features have been developed for this purpose. These features allow discrimination of vehicles from clutter, and classification of vehicles into two classes: targets, comprising military combat types, and non-targets, comprising bulldozers and trucks. The performance of the system is assessed using three baseline missions provided with AdaptSAPS, as well as three additional missions. All performance metrics indicate a distinct learning trend over the course of a mission, with most third and fourth quartile performance levels exceeding 85% correct classification. It has been demonstrated that these performance levels can be maintained even when truth feedback rates are reduced by up to 55% over the course of a mission.

  19. Advanced miniature processing handware for ATR applications

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin (Inventor); Daud, Taher (Inventor); Thakoor, Anikumar (Inventor)

    2003-01-01

    A Hybrid Optoelectronic Neural Object Recognition System (HONORS), is disclosed, comprising two major building blocks: (1) an advanced grayscale optical correlator (OC) and (2) a massively parallel three-dimensional neural-processor. The optical correlator, with its inherent advantages in parallel processing and shift invariance, is used for target of interest (TOI) detection and segmentation. The three-dimensional neural-processor, with its robust neural learning capability, is used for target classification and identification. The hybrid optoelectronic neural object recognition system, with its powerful combination of optical processing and neural networks, enables real-time, large frame, automatic target recognition (ATR).

  20. Towards universal enrichment nanocoating for IR-ATR waveguides.

    PubMed

    Giammarco, James; Zdyrko, Bogdan; Petit, Laeticia; Musgraves, J David; Hu, Juejun; Agarwal, Anu; Kimerling, Lionel; Richardson, Kathleen; Luzinov, Igor

    2011-08-28

    Polymer multilayered nanocoating capable of concentrating various chemical substances at IR-ATR waveguide surfaces is described. The coating affinity to an analyte played a pivotal role in sensitivity enhancement of the IR-ATR measurements, since the unmodified waveguide did not show any analyte detection.

  1. Efficacy of ATR inhibitors as single agents in Ewing sarcoma

    PubMed Central

    Lecona, Emilio; Murga, Matilde; Callen, Elsa; Azorin, Daniel; Alonso, Javier; Lopez, Andres J.; Nussenzweig, Andre; Fernandez-Capetillo, Oscar

    2016-01-01

    Ewing sarcomas (ES) are pediatric bone tumors that arise from a driver translocation, most frequently EWS/FLI1. Current ES treatment involves DNA damaging agents, yet the basis for the sensitivity to these therapies remains unknown. Oncogene-induced replication stress (RS) is a known source of endogenous DNA damage in cancer, which is suppressed by ATR and CHK1 kinases. We here show that ES suffer from high endogenous levels of RS, rendering them particularly dependent on the ATR pathway. Accordingly, two independent ATR inhibitors show in vitro toxicity in ES cell lines as well as in vivo efficacy in ES xenografts as single agents. Expression of EWS/FLI1 or EWS/ERG oncogenic translocations sensitizes non-ES cells to ATR inhibitors. Our data shed light onto the sensitivity of ES to genotoxic agents, and identify ATR inhibitors as a potential therapy for Ewing Sarcomas. PMID:27577084

  2. ATR FTIR Mapping of Leather Fiber Panels

    NASA Astrophysics Data System (ADS)

    Tondi, G.; Grünewald, T.; Petutschnigg, A.; Schnabel, T.

    2015-01-01

    Leather fiber panels are very promising materials for many applications, not only for the easy availability of the constituents but also for their outstanding fi re-retardant properties. These innovative composite panels can be an excellent material for building insulation, and in recent times, the interest of industries in this composite board has considerably arisen. For this reason the discrimination of the components in the leather fiber panels is becoming fundamental in order to ensure their homogeneous properties. A method to characterize the surface of these materials is then required. An ATR FTIR mapping system for the leather fiber panels has been performed with a Perkin-Elmer microscope coupled with a Frontier FTIR spectrometer. The system has successfully allowed transforming the optical image to a chemical one. This technique can be considered as a right tool for routine controls of the surface quality, especially when the leather shavings cannot be optically distinguished.

  3. On the pathway of photoexcited electrons: probing photon-to-electron and photon-to-phonon conversions in silicon by ATR-IR.

    PubMed

    Karabudak, Engin; Yüce, Emre; Schlautmann, Stefan; Hansen, Ole; Mul, Guido; Gardeniers, Han J G E

    2012-08-21

    Photoexcitation and charge carrier thermalization inside semiconductor photocatalysts are two important steps in solar fuel production. Here, photoexcitation and charge carrier thermalization in a silicon wafer are for the first time probed by a novel, yet simple and user-friendly Attenuated Total Reflectance Infrared spectroscopy (ATR-IR) system.

  4. ATR inhibition rewires cellular signaling networks induced by replication stress.

    PubMed

    Wagner, Sebastian A; Oehler, Hannah; Voigt, Andrea; Dalic, Denis; Freiwald, Anja; Serve, Hubert; Beli, Petra

    2016-02-01

    The slowing down or stalling of replication forks is commonly known as replication stress and arises from multiple causes such as DNA lesions, nucleotide depletion, RNA-DNA hybrids, and oncogene activation. The ataxia telangiectasia and Rad3-related kinase (ATR) plays an essential role in the cellular response to replication stress and inhibition of ATR has emerged as therapeutic strategy for the treatment of cancers that exhibit high levels of replication stress. However, the cellular signaling induced by replication stress and the substrate spectrum of ATR has not been systematically investigated. In this study, we employed quantitative MS-based proteomics to define the cellular signaling after nucleotide depletion-induced replication stress and replication fork collapse following ATR inhibition. We demonstrate that replication stress results in increased phosphorylation of a subset of proteins, many of which are involved in RNA splicing and transcription and have previously not been associated with the cellular replication stress response. Furthermore, our data reveal the ATR-dependent phosphorylation following replication stress and discover novel putative ATR target sites on MCM6, TOPBP1, RAD51AP1, and PSMD4. We establish that ATR inhibition rewires cellular signaling networks induced by replication stress and leads to the activation of the ATM-driven double-strand break repair signaling.

  5. On the airworthiness approval of a SAR ATR system

    NASA Astrophysics Data System (ADS)

    Willersinn, Dieter; Jäger, Uwe; Schlatt, Herbert; Stahl, Christoph

    2009-05-01

    A manned platform is to be equipped with a Synthetic Aperture Radar (SAR) based Automatic Target Recognition (ATR) system for precision targeting. The platform's airworthiness has to be approved including the ATR system, i.e. the ATR system needs to be qualified appropriately. Part of the airworthiness approval is a hazard analysis. In general, this is carried out to make sure that the probability of a fatal error in one hour of flight is 10-9 or lower. To date, error probabilities of a SAR-based ATR system, i.e. error probabilities of detection and classification, must be assumed to lie above 10-9 per hour. This is one reason why existing rules of engagement demand "Man-in-the loop", i.e. to display the result of the ATR system to the pilot. Components to the ATR system are consequently a Synthetic Aperture Radar (SAR) sensor an Automatic Target Recognition (ATR) SAR image processing unit, and a Human Machine Interface (HMI) to the pilot. The aim of the work reported in this contribution was to identify those performance features of the thus defined ATR system that are relevant to airworthiness approval, and to define the procedures to determine the feature values. The paper contains the analysis of a reference case of an airworthiness-approved technical system with an error probability above 10-9 per hour and a result display to the pilot. In the light of the analysis results, it concludes with an outlook to the airworthiness approval of the ATR system.

  6. Fuel cell technology for prototype logistic fuel cell mobile systems

    SciTech Connect

    Sederquist, R.A.; Garow, J.

    1995-08-01

    Under the aegis of the Advanced Research Project Agency`s family of programs to develop advanced technology for dual use applications, International Fuel Cells Corporation (IFC) is conducting a 39 month program to develop an innovative system concept for DoD Mobile Electric Power (MEP) applications. The concept is to integrate two technologies, the phosphoric acid fuel cell (PAFC) with an auto-thermal reformer (ATR), into an efficient fuel cell power plant of nominally 100-kilowatt rating which operates on logistic fuels (JP-8). The ATR fuel processor is the key to meeting requirements for MEP (including weight, volume, reliability, maintainability, efficiency, and especially operation on logistic fuels); most of the effort is devoted to ATR development. An integrated demonstration test unit culminates the program and displays the benefits of the fuel cell system, relative to the standard 100-kilowatt MEP diesel engine generator set. A successful test provides the basis for proceeding toward deployment. This paper describes the results of the first twelve months of activity during which specific program aims have remained firm.

  7. IR-ATR investigation of surface anisotropy in silicate glasses

    NASA Astrophysics Data System (ADS)

    Ivanovski, Vladimir; Mayerhöfer, Thomas G.; Kriltz, Antje; Popp, Jürgen

    2017-02-01

    Several samples of flat soda-lime silicate glass were investigated by the Infrared Attenuated Total Reflection (IR-ATR) spectroscopy technique. The specular reflectance spectra together with the results of the performed dispersion analysis and the generated reflectance spectra, using Fresnel equations, suggest that the samples are isotropic. In contrast, spectra recorded by the ATR technique suggest an anisotropic structure on the surface of the specimen different from that in the bulk. This is established through differences in the s- and p-polarized IR-ATR spectra, which cannot be simply transformed into one another employing Fresnel formula for an isotropic case. It appears that this thin film having a structure different from the bulk is larger than the ATR effective penetration depth of the evanescent ray for each incidence angle above the critical one. The investigation suggests C2 symmetry of the SiO4 unit.

  8. Development of scale model imagery for ATR investigations

    NASA Astrophysics Data System (ADS)

    Irvine, John M.; Bergeron, Stuart; Delp, Nathaniel T.; Lewis, Derek R.

    2006-05-01

    Automated target recognition (ATR) methods hold promise for rapid extraction of critical information from imagery data to support military missions. Development of ATR tools generally requires large amounts of imagery data to develop and test algorithms. Deployment of operational ATR systems requires performance validation using operationally relevant imagery. For early algorithm development, however, restrictions on access to such data is a significant impediment, especially for the academic research community. To address this limitation, we have developed a set of grayscale imagery as a surrogate for panchromatic imagery that would be acquired from airborne sensors. This surrogate data set consists of imagery of ground order of battle (GOB) targets in an arid environment. The data set was developed by imaging scale models of these targets set in a scale model background. The imagery spans a range of operating conditions and provides a useful image set for initial explorations of new approaches for ATR development.

  9. Attributed scattering centers for SAR ATR.

    PubMed

    Potter, L C; Moses, R L

    1997-01-01

    High-frequency radar measurements of man-made targets are dominated by returns from isolated scattering centers, such as corners and flat plates. Characterizing the features of these scattering centers provides a parsimonious, physically relevant signal representation for use in automatic target recognition (ATR). In this paper, we present a framework for feature extraction predicated on parametric models for the radar returns. The models are motivated by the scattering behaviour predicted by the geometrical theory of diffraction. For each scattering center, statistically robust estimation of model parameters provides high-resolution attributes including location, geometry, and polarization response. We present statistical analysis of the scattering model to describe feature uncertainty, and we provide a least-squares algorithm for feature estimation. We survey existing algorithms for simplified models, and derive bounds for the error incurred in adopting the simplified models. A model order selection algorithm is given, and an M-ary generalized likelihood ratio test is given for classifying polarimetric responses in spherically invariant random clutter.

  10. Adaptive SAR ATR in likelihood space

    NASA Astrophysics Data System (ADS)

    Duan, Rong; Chen, Ling; Man, Hong

    2005-05-01

    The Adaptive SAR ATR Problem Set (AdaptSAPS) poses a typical "learning with a critic" problem, in which the system-under-test (SUT) is initially trained to characterize a subset of target objects (e.g. T72) and a subset of non-target objects (e.g. clutter), and is to be updated on-line using the Target Truth information. This work proposes an SUT for adaptive SAR imagery exploitation. The system is founded on a novel feature vector generation scheme and Linear Discriminant Analysis (LDA). The proposed feature vector generation scheme partitions SAR image chips into subimage blocks. The distribution density of subimage blocks is fitted as a Gaussian Mixture Model (GMM). Feature vector of each SAR image is composed of log-likelihoods of its subimage blocks on the pre-fitted GMM. Comparing to original SAR image chips, feature vectors generated from log-likelihoods display superior discriminative power. After feature generation, LDA is used to project feature vectors into a 1-dimensional subspace for classification. The performance of the proposed system is evaluated on the AdaptSAPS.

  11. High-resolution SAR ATR performance analysis

    NASA Astrophysics Data System (ADS)

    Douglas, Joel; Burke, Monica; Ettinger, Gil J.

    2004-09-01

    High resolution Synthetic Aperture Radar (SAR) imagery (e.g., four inch or better resolution) contains features not seen in one foot or lower resolution imagery, due to the isolation of the scatterers into separate resolution cells. These features provide the potential for additional discrimination power for Automatic Target Recognition (ATR) systems. In this paper, we analyze the performance of the Real-Time MSTAR (RT-MSTAR) system as a function of image resolution. Performance is measured both in terms of the probability of correct identification on military targets, and also in terms of confuser rejection. The analysis demonstrates two factors that significantly enhance performance. First, use of the high resolution imagery results in much higher probability of correct identification, as demonstrated using Lynx SAR imagery at 4" and 12". Second, incorporating models of the confusers, when available, greatly reduces false alarms, even at higher resolutions. Several new areas of work emerge, including making use of higher-level feature information available in the imagery, and rapid creation of models for vehicles that pose particular confuser rejection challenges.

  12. Infrared ATR: a probe for cellular activation

    NASA Astrophysics Data System (ADS)

    Timlin, Jerilyn A.; Martin, Laura E.; Alam, M. Kathleen; Haaland, David M.; Garrison, Kristen; Lyons, C. Richard; Hjelle, Brian

    2002-02-01

    We employ infrared spectroscopy (IR) with attenuated total reflectance (ATR) as a sampling technique to monitor live and dried RAW cells (a murine macrophage cell line) during activation with g-interferon and lipopolysaccharide. By comparing the spectra of activated cells at various time points to the spectra of healthy control cells, we identify spectral bands associated with nucleic acids that are markers for the cell activation process. These spectral changes are slight and can be complicated with the normal metabolic changes that occur within cells. We will discuss the use of data pretreatment strategies to accurately correct for the contribution of the buffer to the live cell spectra. We find the standard background correction method inadequate for concentrated solutions of cells. Data presented shows the severe effect incorrect background subtraction has on the cell spectra. We report a more accurate correction for phosphate buffer spectral contribution using an interactive subtraction of the buffer spectrum. We will show classification of dried control and activated macrophage cell spectra using partial-least squares analysis with multiplicative scatter correction.

  13. ATR-IR spectroscopy as applied to nucleic acid films

    NASA Astrophysics Data System (ADS)

    Stepanyugin, Andriy V.; Samijlenko, Svitlana P.; Martynenko, Olena I.; Hovorun, Dmytro M.

    2005-07-01

    For the first time the ATR technique was applied to obtain IR absorption spectra of DNA and RNA dry films. There was worked out procedure of the nucleic acid removal from germanium plate, which obviously was a main obstacle to application of ATR-IR spectroscopy to nucleic acids. This technique of IR spectroscopy was applied to confirmation of RNA tropism of aurin tricarboxylic acid observed by molecular biological methods.

  14. ATR National Scientific User Facility 2009 Annual Report

    SciTech Connect

    Todd R. Allen; Mitchell K. Meyer; Frances Marshall; Mary Catherine Thelen; Jeff Benson

    2010-11-01

    This report describes activities of the ATR NSUF from FY-2008 through FY-2009 and includes information on partner facilities, calls for proposals, users week and education programs. The report also contains project information on university research projects that were awarded by ATR NSUF in the fiscal years 2008 & 2009. This research is university-proposed researcher under a user facility agreement. All intellectual property from these experiments belongs to the university per the user agreement.

  15. Corrosion of spent Advanced Test Reactor fuel

    SciTech Connect

    Lundberg, L.B.; Croson, M.L.

    1994-11-01

    The results of a study of the condition of spent nuclear fuel elements from the Advanced Test Reactor (ATR) currently being stored underwater at the Idaho National Engineering Laboratory (INEL) are presented. This study was motivated by a need to estimate the corrosion behavior of dried, spent ATR fuel elements during dry storage for periods up to 50 years. The study indicated that the condition of spent ATR fuel elements currently stored underwater at the INEL is not very well known. Based on the limited data and observed corrosion behavior in the reactor and in underwater storage, it was concluded that many of the fuel elements currently stored under water in the facility called ICPP-603 FSF are in a degraded condition, and it is probable that many have breached cladding. The anticipated dehydration behavior of corroded spent ATR fuel elements was also studied, and a list of issues to be addressed by fuel element characterization before and after forced drying of the fuel elements and during dry storage is presented.

  16. Performance model for joint tracking and ATR with HRR radar

    NASA Astrophysics Data System (ADS)

    Cong, Shan; Hong, Lang; Blasch, Erik

    2008-04-01

    Joint tracking and ATR with HRR radar is an important field of research in recent years. This paper addresses the issue of end-to-end performance modeling for HRR radar based joint tracking and ATR system under various operating conditions. To this end, an ATR system with peak location and amplitude as features is considered. A complete set of models are developed to capture the statistics in all stages of processing, including HRR signal, extracted features, Baysian classifier and tracker. In particular, we demonstrate that the effect of operating conditions on feature can be represented through a random variable with Log-normal distribution. Then, the result is extended to predicting the system performance under specified operating conditions. Although this paper is developed based on a type of ATR and tracking system, the result indicates the trend of the performance for general joint ATR and tracking system over operating conditions. It also provides guidance to how the empirical performance model of a general joint tracking and ATR system shall be constructed.

  17. Applications of ATR-FTIR spectroscopic imaging to biomedical samples.

    PubMed

    Kazarian, S G; Chan, K L A

    2006-07-01

    FTIR spectroscopic imaging in ATR (Attenuated Total Reflection) mode is a powerful tool for studying biomedical samples. This paper summarises recent advances in the applications of ATR-FTIR imaging to dissolution of pharmaceutical formulations and drug release. The use of two different ATR accessories to obtain chemical images of formulations in contact with water as a function of time is demonstrated. The innovative use of the diamond ATR accessory allowed in situ imaging of tablet compaction and dissolution. ATR-FTIR imaging was also applied to obtain images of the surface of skin and the spatial distribution of protein and lipid rich domains was obtained. Chemical images of cross-section of rabbit aorta were obtained using a diamond ATR accessory and the possibility of in situ imaging of arterial samples in contact with aqueous solution was demonstrated for the first time. This experiment opens an opportunity to image arterial samples in contact with solutions containing drug molecules. This approach may help in understanding the mechanisms of treatment of atherosclerosis.

  18. Method for fast start of a fuel processor

    DOEpatents

    Ahluwalia, Rajesh K.; Ahmed, Shabbir; Lee, Sheldon H. D.

    2008-01-29

    An improved fuel processor for fuel cells is provided whereby the startup time of the processor is less than sixty seconds and can be as low as 30 seconds, if not less. A rapid startup time is achieved by either igniting or allowing a small mixture of air and fuel to react over and warm up the catalyst of an autothermal reformer (ATR). The ATR then produces combustible gases to be subsequently oxidized on and simultaneously warm up water-gas shift zone catalysts. After normal operating temperature has been achieved, the proportion of air included with the fuel is greatly diminished.

  19. Assessment of COTS IR image simulation tools for ATR development

    NASA Astrophysics Data System (ADS)

    Seidel, Heiko; Stahl, Christoph; Bjerkeli, Frode; Skaaren-Fystro, Paal

    2005-05-01

    Following the tendency of increased use of imaging sensors in military aircraft, future fighter pilots will need onboard artificial intelligence e.g. ATR for aiding them in image interpretation and target designation. The European Aeronautic Defence and Space Company (EADS) in Germany has developed an advanced method for automatic target recognition (ATR) which is based on adaptive neural networks. This ATR method can assist the crew of military aircraft like the Eurofighter in sensor image monitoring and thereby reduce the workload in the cockpit and increase the mission efficiency. The EADS ATR approach can be adapted for imagery of visual, infrared and SAR sensors because of the training-based classifiers of the ATR method. For the optimal adaptation of these classifiers they have to be trained with appropriate and sufficient image data. The training images must show the target objects from different aspect angles, ranges, environmental conditions, etc. Incomplete training sets lead to a degradation of classifier performance. Additionally, ground truth information i.e. scenario conditions like class type and position of targets is necessary for the optimal adaptation of the ATR method. In Summer 2003, EADS started a cooperation with Kongsberg Defence & Aerospace (KDA) from Norway. The EADS/KDA approach is to provide additional image data sets for training-based ATR through IR image simulation. The joint study aims to investigate the benefits of enhancing incomplete training sets for classifier adaptation by simulated synthetic imagery. EADS/KDA identified the requirements of a commercial-off-the-shelf IR simulation tool capable of delivering appropriate synthetic imagery for ATR development. A market study of available IR simulation tools and suppliers was performed. After that the most promising tool was benchmarked according to several criteria e.g. thermal emission model, sensor model, targets model, non-radiometric image features etc., resulting in a

  20. Analysis of a Partial MOX Core Design with Tritium Targets for Light Water Reactors

    SciTech Connect

    Anistratov, Dmitriy Y.; Adams, Marvin L.

    1998-04-19

    This report constitutes tangible and verifiable deliverable associated with the task To study the effects of using WG MOX fuel in tritium-producing LWR” of the subproject Water Reactor Options for Disposition of Plutonium. The principal investigators of this subproject are Naeem M. Abdurrahman of the University of Texas at Austin and Marvin L. Adams of Texas A&M University. This work was sponsored by the Amarillo National Resource Center for Plutonium.

  1. FLUX SENSOR EVALUATIONS AT THE ATR CRITICAL FACILITY

    SciTech Connect

    Troy Unruh; Joy Rempe; David Nigg; George Imel; Jason Harris; Eric Bonebrake

    2010-11-01

    The Advanced Test Reactor (ATR) and the ATR Critical (ATRC) facilities lack real-time methods for detecting thermal neutron flux and fission reaction rates for irradiation capsules. Direct measurements of the actual power deposited into a test are now possible without resorting to complicated correction factors. In addition, it is possible to directly measure minor actinide fission reaction rates and to provide time-dependent monitoring of the fission reaction rate or fast/thermal flux during transient testing. A joint Idaho State University /Idaho National Laboratory ATR National Scientific User Facility (ATR NSUF) project was recently initiated to evaluate new real-time state-of-the-art in-pile flux detection sensors. Initially, the project is comparing the accuracy, response time, and long duration performance of French Atomic Energy Commission (CEA)-developed miniature fission chambers, specialized self-powered neutron detectors (SPNDs) by the Argentinean National Energy Commission (CNEA), specially developed commercial SPNDs, and back-to-back fission (BTB) chambers developed by Argonne National Laboratory (ANL). As discussed in this paper, specialized fixturing and software was developed by INL to facilitate these joint ISU/INL evaluations. Calculations were performed by ISU to assess the performance of and reduce uncertainties in flux detection sensors and compare data obtained from these sensors with existing integral methods employed at the ATRC. Ultimately, project results will be used to select the detector that can provide the best online regional ATRC power measurement. It is anticipated that project results may offer the potential to increase the ATRC’s current power limit and its ability to perform low-level irradiation experiments. In addition, results from this effort will provide insights about the viability of using these detectors in the ATR. Hence, this effort complements current activities to improve ATR software tools, computational

  2. Profiling of UV-induced ATM/ATR signaling pathways

    PubMed Central

    Stokes, Matthew P.; Rush, John; MacNeill, Joan; Ren, Jian Min; Sprott, Kam; Nardone, Julie; Yang, Vicky; Beausoleil, Sean A.; Gygi, Steven P.; Livingstone, Mark; Zhang, Hui; Polakiewicz, Roberto D.; Comb, Michael J.

    2007-01-01

    To ensure survival in the face of genomic insult, cells have evolved complex mechanisms to respond to DNA damage, termed the DNA damage checkpoint. The serine/threonine kinases ataxia telangiectasia-mutated (ATM) and ATM and Rad3-related (ATR) activate checkpoint signaling by phosphorylating substrate proteins at SQ/TQ motifs. Although some ATM/ATR substrates (Chk1, p53) have been identified, the lack of a more complete list of substrates limits current understanding of checkpoint pathways. Here, we use immunoaffinity phosphopeptide isolation coupled with mass spectrometry to identify 570 sites phosphorylated in UV-damaged cells, 498 of which are previously undescribed. Semiquantitative analysis yielded 24 known and 192 previously uncharacterized sites differentially phosphorylated upon UV damage, some of which were confirmed by SILAC, Western blotting, and immunoprecipitation/Western blotting. ATR-specific phosphorylation was investigated by using a Seckel syndrome (ATR mutant) cell line. Together, these results provide a rich resource for further deciphering ATM/ATR signaling and the pathways mediating the DNA damage response. PMID:18077418

  3. ATR contributes to telomere maintenance in human cells

    PubMed Central

    Pennarun, Gaëlle; Hoffschir, Françoise; Revaud, Deborah; Granotier, Christine; Gauthier, Laurent R.; Mailliet, Patrick; Biard, Denis S.; Boussin, François D.

    2010-01-01

    Telomere maintenance is essential to preserve genomic stability and involves several telomere-specific proteins as well as DNA replication and repair proteins. The kinase ATR, which has a crucial function in maintaining genome integrity from yeast to human, has been shown to be involved in telomere maintenance in several eukaryotic organisms, including yeast, Arabidopsis and Drosophila. However, its role in telomere maintenance in mammals remains poorly explored. Here, we report by using telomere-fluorescence in situ hybridization (Telo-FISH) on metaphase chromosomes that ATR deficiency causes telomere instability both in primary human fibroblasts from Seckel syndrome patients and in HeLa cells. The telomere aberrations resulting from ATR deficiency (i.e. sister telomere fusions and chromatid-type telomere aberrations) are mainly generated during and/or after telomere replication, and involve both leading and lagging strand telomeres as shown by chromosome orientation-FISH (CO-FISH). Moreover, we show that ATR deficiency strongly sensitizes cells to the G-quadruplex ligand 360A, enhancing sister telomere fusions and chromatid-type telomere aberrations involving specifically the lagging strand telomeres. Altogether, these data reveal that ATR plays a critical role in telomere maintenance during and/or after telomere replication in human cells. PMID:20147462

  4. Thermal Hydraulic Effect of Fuel Plate Surface Roughness

    SciTech Connect

    Donna Post Guillen; Timothy S. Yoder

    2008-09-01

    This study presents surface roughness measurements characteristic of the pre-film layer applied to a typical Advanced Test Reactor (ATR) fuel plate. This data is used to estimate the friction factor for thermal hydraulic flow calculations of a Gas Test Loop (GTL) system proposed for incorporation into ATR to provide a fast neutron flux environment for the testing of nuclear fuels and materials. To attain the required neutron flux, the design includes booster fuel plates clad with the same aluminum alloy as the ATR driver fuel and cooled with water supplied by the ATR primary coolant pumps. The objectives of this study are to: (1) determine the surface roughness of the protective boehmite layer applied to the ATR driver fuel prior to reactor operations in order to specify the machining tolerances for the surface finish on simulated booster fuel plates in a GTL hydraulic flow test model, and (2) assess the consequent thermal hydraulic impact due to surface roughness on the coolability of the booster fuel with a similar pre-film layer applied. While the maximum roughness of this coating is specified to be 1.6 µm (63 microinches), no precise data on the actual roughness were available. A representative sample coupon autoclaved with the ATR driver fuel to produce the pre-film coating was analyzed using optical profilometry. Measurements yielded a mean surface roughness of 0.53 µm (21 microinches). Results from a sensitivity study show that a ±15% deviation from the mean measured surface finish would have a minimal effect on coolant temperature, coolant flow rate, and fuel temperature. However, frictional losses from roughnesses greater than 1.5 µm (~60 microinches) produce a marked decrease in flow rate, causing fuel and coolant temperatures to rise sharply.

  5. Homeostatic regulation of meiotic DSB formation by ATM/ATR

    SciTech Connect

    Cooper, Tim J.; Wardell, Kayleigh; Garcia, Valerie; Neale, Matthew J.

    2014-11-15

    Ataxia–telangiectasia mutated (ATM) and RAD3-related (ATR) are widely known as being central players in the mitotic DNA damage response (DDR), mounting responses to DNA double-strand breaks (DSBs) and single-stranded DNA (ssDNA) respectively. The DDR signalling cascade couples cell cycle control to damage-sensing and repair processes in order to prevent untimely cell cycle progression while damage still persists [1]. Both ATM/ATR are, however, also emerging as essential factors in the process of meiosis; a specialised cell cycle programme responsible for the formation of haploid gametes via two sequential nuclear divisions. Central to achieving accurate meiotic chromosome segregation is the introduction of numerous DSBs spread across the genome by the evolutionarily conserved enzyme, Spo11. This review seeks to explore and address how cells utilise ATM/ATR pathways to regulate Spo11-DSB formation, establish DSB homeostasis and ensure meiosis is completed unperturbed.

  6. ATR NATIONAL SCIENTIFIC USER FACILITY INSTRUMENTATION ENHANCEMENT EFFORTS

    SciTech Connect

    Joy L. Rempe; Mitchell K. Meyer

    2009-04-01

    A key component of the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) effort is to enhance instrumentation techniques available to users conducting irradiation tests in this unique facility. In particular, development of sensors capable of providing ‘real-time’ measurements of key irradiation parameters is emphasized because of their potential to offer increased fidelity data and reduced post-test examination costs. This paper describes the strategy for identifying new instrumentation needed for ATR irradiations and the program underway to develop and evaluate new sensors to address these needs. Accomplishments from this program are illustrated by describing several new sensors now available to users of the ATR NSUF. In addition, progress is reported on current research efforts to provide users improved in-pile instrumentation.

  7. Homeostatic regulation of meiotic DSB formation by ATM/ATR.

    PubMed

    Cooper, Tim J; Wardell, Kayleigh; Garcia, Valerie; Neale, Matthew J

    2014-11-15

    Ataxia-telangiectasia mutated (ATM) and RAD3-related (ATR) are widely known as being central players in the mitotic DNA damage response (DDR), mounting responses to DNA double-strand breaks (DSBs) and single-stranded DNA (ssDNA) respectively. The DDR signalling cascade couples cell cycle control to damage-sensing and repair processes in order to prevent untimely cell cycle progression while damage still persists [1]. Both ATM/ATR are, however, also emerging as essential factors in the process of meiosis; a specialised cell cycle programme responsible for the formation of haploid gametes via two sequential nuclear divisions. Central to achieving accurate meiotic chromosome segregation is the introduction of numerous DSBs spread across the genome by the evolutionarily conserved enzyme, Spo11. This review seeks to explore and address how cells utilise ATM/ATR pathways to regulate Spo11-DSB formation, establish DSB homeostasis and ensure meiosis is completed unperturbed.

  8. Hydraulic Shuttle Irradiation System (HSIS) Recently Installed in the Advanced Test Reactor (ATR)

    SciTech Connect

    A. Joseph Palmer; Gerry L. McCormick; Shannon J. Corrigan

    2010-06-01

    a Readiness Assessment in November 2009. The HSIS is a key component of the ATR National Scientific User Facility (NSUF) operated by Battelle Energy Alliance, LLC and is available to a wide variety of university researchers for nuclear fuels and materials experiments as well as medical isotope research and production.

  9. Criticality safety evaluation for the Advanced Test Reactor enhanced low enriched uranium fuel elements

    SciTech Connect

    Montierth, Leland M.

    2016-07-19

    The Global Threat Reduction Initiative (GTRI) convert program is developing a high uranium density fuel based on a low enriched uranium (LEU) uranium-molybdenum alloy. Testing of prototypic GTRI fuel elements is necessary to demonstrate integrated fuel performance behavior and scale-up of fabrication techniques. GTRI Enhanced LEU Fuel (ELF) elements based on the ATR-Standard Size elements (all plates fueled) are to be fabricated for testing in the Advanced Test Reactor (ATR). While a specific ELF element design will eventually be provided for detailed analyses and in-core testing, this criticality safety evaluation (CSE) is intended to evaluate a hypothetical ELF element design for criticality safety purposes. Existing criticality analyses have analyzed Standard (HEU) ATR elements from which controls have been derived. This CSE documents analysis that determines the reactivity of the hypothetical ELF fuel elements relative to HEU ATR elements and whether the existing HEU ATR element controls bound the ELF element. The initial calculations presented in this CSE analyzed the original ELF design, now referred to as Mod 0.1. In addition, as part of a fuel meat thickness optimization effort for reactor performance, other designs have been evaluated. As of early 2014 the most current conceptual designs are Mk1A and Mk1B, that were previously referred to as conceptual designs Mod 0.10 and Mod 0.11, respectively. Revision 1 evaluates the reactivity of the ATR HEU Mark IV elements for a comparison with the Mark VII elements.

  10. ATR spectra on boundary with mixture containing organic substances

    NASA Astrophysics Data System (ADS)

    Schelokov, R. V.; Yatsishen, V. V.

    2005-02-01

    The problem of not destroying diagnostics and dosing of radiation at laser therapy is one of important in medicine. Therefore the purpose of our work is development of method ATR for diagnostics and researches in biomedicine. In this work as objects of consideration were: a mixture of nicotine with water, a mixture of an ascorbic acid with water and surface lesions of an eye cornea by a herpes virus. Results of our consideration are the ATR spectra defined at different concentration of organic substances and virions.

  11. Project Description Advanced Fuel Cycle Initiative AFC-2A and AFC-2B Experiments

    SciTech Connect

    AFCI AFC-2A and AFC-2B Experiments Project Executi

    2007-03-01

    The proposed AFC-2A and AFC-2B irradiation experiments are a continuation of the AFC-1 fuel test series currently in progress in the ATR. This document discusses the experiments and the planned activities that will take place.

  12. Gas Test Loop Booster Fuel Hydraulic Testing

    SciTech Connect

    Gas Test Loop Hydraulic Testing Staff

    2006-09-01

    The Gas Test Loop (GTL) project is for the design of an adaptation to the Advanced Test Reactor (ATR) to create a fast-flux test space where fuels and materials for advanced reactor concepts can undergo irradiation testing. Incident to that design, it was found necessary to make use of special booster fuel to enhance the neutron flux in the reactor lobe in which the Gas Test Loop will be installed. Because the booster fuel is of a different composition and configuration from standard ATR fuel, it is necessary to qualify the booster fuel for use in the ATR. Part of that qualification is the determination that required thermal hydraulic criteria will be met under routine operation and under selected accident scenarios. The Hydraulic Testing task in the GTL project facilitates that determination by measuring flow coefficients (pressure drops) over various regions of the booster fuel over a range of primary coolant flow rates. A high-fidelity model of the NW lobe of the ATR with associated flow baffle, in-pile-tube, and below-core flow channels was designed, constructed and located in the Idaho State University Thermal Fluids Laboratory. A circulation loop was designed and constructed by the university to provide reactor-relevant water flow rates to the test system. Models of the four booster fuel elements required for GTL operation were fabricated from aluminum (no uranium or means of heating) and placed in the flow channel. One of these was instrumented with Pitot tubes to measure flow velocities in the channels between the three booster fuel plates and between the innermost and outermost plates and the side walls of the flow annulus. Flow coefficients in the range of 4 to 6.5 were determined from the measurements made for the upper and middle parts of the booster fuel elements. The flow coefficient for the lower end of the booster fuel and the sub-core flow channel was lower at 2.3.

  13. USE OF SILICON CARBIDE MONITORS IN ATR IRRADIATION TESTING

    SciTech Connect

    K. L. Davis; B. Chase; T. Unruh; D. Knudson; J. L. Rempe

    2012-07-01

    In April 2007, the Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) to advance US leadership in nuclear science and technology. By attracting new users from universities, laboratories, and industry, the ATR will support basic and applied nuclear research and development and help address the nation's energy security needs. In support of this new program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. Although most efforts emphasize sensors capable of providing real-time data, selected tasks have been completed to enhance sensors provided in irradiation locations where instrumentation leads cannot be included, such as drop-in capsule and Hydraulic Shuttle Irradiation System (HSIS) or 'rabbit' locations. For example, silicon carbide (SiC) monitors are now available to detect peak irradiation temperatures between 200°C and 800°C. Using a resistance measurement approach, specialized equipment installed at INL's High Temperature Test Laboratory (HTTL) and specialized procedures were developed to ensure that accurate peak irradiation temperature measurements are inferred from SiC monitors irradiated at the ATR. Comparison examinations were completed by INL to demonstrate this capability, and several programs currently rely on SiC monitors for peak temperature detection. This paper discusses the use of SiC monitors at the ATR, the process used to evaluate them at the HTTL, and presents representative measurements taken using SiC monitors.

  14. ATR-FTIR investigations of plasticizer diffusion in polymers

    NASA Astrophysics Data System (ADS)

    Miser, C. S.; McNesby, Kevin L.; Pesce-Rodriguez, Rose A.; Fifer, Robert A.

    1992-03-01

    An attenuated total reflectance FTIR (ATR-FTIR) technique has been developed for measuring the diffusion coefficients of liquids in polymer films. Data is being obtained for diffusion of plasticizers in nitrocellulose (NC), cellulose acetate butyrate (CAB), and NC/CAB mixtures.

  15. WWOX modulates the ATR-mediated DNA damage checkpoint response.

    PubMed

    Abu-Odeh, Mohammad; Hereema, Nyla A; Aqeilan, Rami I

    2016-01-26

    For many decades genomic instability is considered one of the hallmarks of cancer. Role of the tumor suppressor WWOX (WW domain-containing oxidoreductase) in DNA damage response upon double strand breaks has been recently revealed. Here we demonstrate unforeseen functions for WWOX upon DNA single strand breaks (SSBs) checkpoint activation. We found that WWOX levels are induced following SSBs and accumulate in the nucleus. WWOX deficiency is associated with reduced activation of ataxia telangiectasia and Rad3-related protein (ATR) checkpoint proteins and increased chromosomal breaks. At the molecular level, we show that upon SSBs WWOX is modified at lysine 274 by ubiquitination mediated by the ubiquitin E3 ligase ITCH and interacts with ataxia telangiectasia-mutated (ATM). Interestingly, ATM inhibition was associated with reduced activation of ATR checkpoint proteins suggesting that WWOX manipulation of ATR checkpoint proteins is ATM-dependent. Taken together, the present findings indicate that WWOX plays a key role in ATR checkpoint activation, while its absence might facilitate genomic instability.

  16. WWOX modulates the ATR-mediated DNA damage checkpoint response

    PubMed Central

    Abu-Odeh, Mohammad; Hereema, Nyla A.; Aqeilan, Rami I.

    2016-01-01

    For many decades genomic instability is considered one of the hallmarks of cancer. Role of the tumor suppressor WWOX (WW domain-containing oxidoreductase) in DNA damage response upon double strand breaks has been recently revealed. Here we demonstrate unforeseen functions for WWOX upon DNA single strand breaks (SSBs) checkpoint activation. We found that WWOX levels are induced following SSBs and accumulate in the nucleus. WWOX deficiency is associated with reduced activation of ataxia telangiectasia and Rad3-related protein (ATR) checkpoint proteins and increased chromosomal breaks. At the molecular level, we show that upon SSBs WWOX is modified at lysine 274 by ubiquitination mediated by the ubiquitin E3 ligase ITCH and interacts with ataxia telangiectasia-mutated (ATM). Interestingly, ATM inhibition was associated with reduced activation of ATR checkpoint proteins suggesting that WWOX manipulation of ATR checkpoint proteins is ATM-dependent. Taken together, the present findings indicate that WWOX plays a key role in ATR checkpoint activation, while its absence might facilitate genomic instability. PMID:26675548

  17. Mec1/ATR, the Program Manager of Nucleic Acids Inc.

    PubMed Central

    Feng, Wenyi

    2016-01-01

    Eukaryotic cells are equipped with surveillance mechanisms called checkpoints to ensure proper execution of cell cycle events. Among these are the checkpoints that detect DNA damage or replication perturbations and coordinate cellular activities to maintain genome stability. At the forefront of damage sensing is an evolutionarily conserved molecule, known respectively in budding yeast and humans as Mec1 (Mitosis entry checkpoint 1) and ATR (Ataxia telangiectasia and Rad3-related protein). Through phosphorylation, Mec1/ATR activates downstream components of a signaling cascade to maintain nucleotide pool balance, protect replication fork integrity, regulate activation of origins of replication, coordinate DNA repair, and implement cell cycle delay. This list of functions continues to expand as studies have revealed that Mec1/ATR modularly interacts with various protein molecules in response to different cellular cues. Among these newly assigned functions is the regulation of RNA metabolism during checkpoint activation and the coordination of replication–transcription conflicts. In this review, I will highlight some of these new functions of Mec1/ATR with a focus on the yeast model organism. PMID:28036033

  18. AGR-2 Final Data Qualification Report for U.S. Capsules - ATR Cycles 147A Through 154B

    SciTech Connect

    Pham, Binh T.; Einerson, Jeffrey J.

    2014-07-01

    This report provides the data qualification status of AGR-2 fuel irradiation experimental data in four U.S. capsules from all 15 Advanced Test Reactor (ATR) Cycles 147A, 148A, 148B, 149A, 149B, 150A, 150B, 151A, 151B, 152A, 152B, 153A, 153B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Thus, this report covers data qualification status for the entire AGR-2 irradiation and will replace four previously issued AGR-2 data qualification reports (e.g., INL/EXT-11-22798, INL/EXT-12-26184, INL/EXT-13-29701, and INL/EXT-13-30750). During AGR-2 irradiation, two cycles, 152A and 153A, occurred when the ATR core was briefly at low power, so AGR-2 irradiation data are not used for physics and thermal calculations. Also, two cycles, 150A and 153B, are Power Axial Locator Mechanism (PALM) cycles when the ATR power is higher than during normal cycles. During the first PALM cycle, 150A, the experiment was temporarily moved from the B-12 location to the ATR water canal and during the second PALM cycle, 153B, the experiment was temporarily moved from the B-12 location to the I-24 location to avoid being overheated. During the “Outage” cycle, 153A, seven flow meters were installed downstream from seven Fission Product Monitoring System (FPMS) monitors to measure flows from the monitors and these data are included in the NDMAS database.

  19. Score-based SAR ATR performance model with operating condition dependencies

    NASA Astrophysics Data System (ADS)

    Kaufman, Vladimir I.; Ross, Timothy D.; Lavely, Eugene M.; Blasch, Erik P.

    2007-04-01

    Automatic target recognition (ATR) performance models are needed for online adaptation and for effective use (e.g., in fusion) of ATR products. We present empirical models focused on synthetic aperture radar (SAR) ATR algorithms. These models are not ATR algorithms in themselves; rather they are models of ATRs developed with the intention of capturing the behavior, at least on a statistical basis, of a reference ATR algorithm. The model covariates (or inputs) might include the ATR operating conditions (sensor, target, and environment), ATR training parameters, etc. The model might produce performance metrics (Pid, Pd, Pfa, etc.) or individual ATR decisions. "Scores" are an intermediate product of many ATRs, which then go through a relatively simple decision rule. Our model has a parallel structure, first modeling the score production and then mapping scores to model outputs. From a regression perspective, it is impossible to predict individual ATR outcomes for all possible values of this covariate space since samples are only available for small subsets of the total space. Given this limitation, and absent a purely theoretical model meaningfully matched to the true complexity of this problem, our approach is to examine the empirical behavior of scores across various operating conditions, and identify trends and characteristics of the scores that are apparently predictable. Many of the scores available for training are in so-called standard operating conditions (SOC), and a far smaller number are in so-called extended operating conditions (EOCs). The influence of the EOCs on scores and ATR decisions are examined in detail.

  20. Comparison between ATR-IR, Raman, concatenated ATR-IR and Raman spectroscopy for the determination of total antioxidant capacity and total phenolic content of Chinese rice wine.

    PubMed

    Wu, Zhengzong; Xu, Enbo; Long, Jie; Pan, Xiaowei; Xu, Xueming; Jin, Zhengyu; Jiao, Aiquan

    2016-03-01

    The application of attenuated total reflectance infrared spectroscopy (ATR-IR), Raman spectroscopy (RS) and combination of ATR-IR and RS for measurements of total antioxidant capacity (TAC) and total phenolic content (TPC) of Chinese rice wine (CRW) were investigated in this study. Synergy interval partial least-squares (SiPLS), support vector machine (SVM) and principal component analysis (PCA) were applied to process the merged data from two individual instruments. It was observed that the performances of models based on the RS spectra were better than those based on the ATR-IR spectra. In addition, SVM models based on the efficient information extracted from ATR-IR and RS spectra were superior to PLS models based on the same information and PLS models based on ATR-IR or RS spectra. The overall results demonstrated that integrating ATR-IR and RS was possible and could improve the prediction accuracy of TAC and TPC in CRWs.

  1. Integrate knowledge acquisition with target recognition through closed-loop ATR

    NASA Astrophysics Data System (ADS)

    Yu, Ssu-Hsin; McLaughlin, Pat; Zatezalo, Aleksandar; Hsiao, Kai-yuh; Boskovic, Jovan

    2015-05-01

    Automatic Target Recognition (ATR) algorithm performance is highly dependent on the sensing conditions under which the input data is collected. Open-loop fly-bys often produce poor results due to less than ideal measurement conditions. In addition, ATR algorithms must be extremely complicated to handle the diverse range of inputs with a resulting reduction in overall performance and increase in complexity. Our approach, closed-loop ATR (CL-ATR), focuses on improving the quality of information input to the ATR algorithms by optimizing motion, sensor settings and team (vehicle-vehicle-human) collaboration to dramatically improve classification accuracy. By managing the data collection guided by predicted ATR performance gain, we increase the information content of the data and thus dramatically improve ATR performance with existing ATR algorithms. CL-ATR has two major functions; first, an ATR utility function, which represents the performance sensitivity of ATR produced classification labels as a function of parameters that correlate to vehicle/sensor states. This utility function is developed off-line and is often available from the original ATR study as a confusion matrix, or it can be derived through simulation without direct access to the inner working of the ATR algorithm. The utility function is inserted into our CLATR framework to autonomously control the vehicle/sensor. Second, an on-board planner maps the utility function into vehicle position and sensor collection plans. Because we only require the utility function on-board, we can activate any ATR algorithm onto a unmanned aerial vehicle (UAV) platform no matter how complex. This pairing of ATR performance profiles with vehicle/sensor controls creates a unique and powerful active perception behavior.

  2. Integrating visual learning within a model-based ATR system

    NASA Astrophysics Data System (ADS)

    Carlotto, Mark; Nebrich, Mark

    2017-05-01

    Automatic target recognition (ATR) systems, like human photo-interpreters, rely on a variety of visual information for detecting, classifying, and identifying manmade objects in aerial imagery. We describe the integration of a visual learning component into the Image Data Conditioner (IDC) for target/clutter and other visual classification tasks. The component is based on an implementation of a model of the visual cortex developed by Serre, Wolf, and Poggio. Visual learning in an ATR context requires the ability to recognize objects independent of location, scale, and rotation. Our method uses IDC to extract, rotate, and scale image chips at candidate target locations. A bootstrap learning method effectively extends the operation of the classifier beyond the training set and provides a measure of confidence. We show how the classifier can be used to learn other features that are difficult to compute from imagery such as target direction, and to assess the performance of the visual learning process itself.

  3. A SAR ATR algorithm based on coherent change detection

    SciTech Connect

    Harmony, D.W.

    2000-12-01

    This report discusses an automatic target recognition (ATR) algorithm for synthetic aperture radar (SAR) imagery that is based on coherent change detection techniques. The algorithm relies on templates created from training data to identify targets. Objects are identified or rejected as targets by comparing their SAR signatures with templates using the same complex correlation scheme developed for coherent change detection. Preliminary results are presented in addition to future recommendations.

  4. Key features for ATA / ATR database design in missile systems

    NASA Astrophysics Data System (ADS)

    Özertem, Kemal Arda

    2017-05-01

    Automatic target acquisition (ATA) and automatic target recognition (ATR) are two vital tasks for missile systems, and having a robust detection and recognition algorithm is crucial for overall system performance. In order to have a robust target detection and recognition algorithm, an extensive image database is required. Automatic target recognition algorithms use the database of images in training and testing steps of algorithm. This directly affects the recognition performance, since the training accuracy is driven by the quality of the image database. In addition, the performance of an automatic target detection algorithm can be measured effectively by using an image database. There are two main ways for designing an ATA / ATR database. The first and easy way is by using a scene generator. A scene generator can model the objects by considering its material information, the atmospheric conditions, detector type and the territory. Designing image database by using a scene generator is inexpensive and it allows creating many different scenarios quickly and easily. However the major drawback of using a scene generator is its low fidelity, since the images are created virtually. The second and difficult way is designing it using real-world images. Designing image database with real-world images is a lot more costly and time consuming; however it offers high fidelity, which is critical for missile algorithms. In this paper, critical concepts in ATA / ATR database design with real-world images are discussed. Each concept is discussed in the perspective of ATA and ATR separately. For the implementation stage, some possible solutions and trade-offs for creating the database are proposed, and all proposed approaches are compared to each other with regards to their pros and cons.

  5. Neutronics analysis of the DHCE experiment in ATR-ITV

    SciTech Connect

    Gomes, I.C.; Smith, D.L.; Tsai, H.

    1997-08-01

    The preliminary analysis of the DHCE experiments in the ITV and ATR was performed and its was concluded that such a vehicle is suitable for this kind of experiment. It is recommended to place an extra filter material in the thermocouple sleeve (such as B-10), to improve the helium to dpa ratio profile during irradiation. Also, it was concluded that a preliminary estimation of period of time for replacement of the external filter would be around 5 dps`s.

  6. Surface analysis of powder binary mixtures with ATR FTIR spectroscopy.

    PubMed

    Planinsek, Odon; Planinsek, Daniela; Zega, Anamarija; Breznik, Matej; Srcic, Stane

    2006-08-17

    Attenuated Total Reflectance Fourier Transform Infra Red spectroscopy (ATR FTIR) has been used for surface analysis of powder mixtures. The appearance of one component on the surface of the mixture in greater amounts than that expected from the mass or volume ratio was quantified. Coloured mixtures containing methyl orange were analysed. They contained proportions of components from 0% to 100% in steps of 10%. Mixtures of non-sieved powders of methyl orange and Povidone were dark red when containing only 20% of methyl orange, indicating that particles of methyl orange were present on the surface of the mixture in higher amounts than expected from the mass ratios. Mixtures of methyl orange and Mg stearate, on the other hand, were a light colour, showing the presence of more Mg stearate on the surface than expected. Visual observations correlated with semiquantitative surface concentration determination by ATR FTIR spectroscopy using specific peaks of each component. Quantitative determination of components on the surface of the mixture, using the Beer Lambert law, was possible when characteristic peaks for the first component did not overlap with those of the other component. A non-linear correlation between peak height and concentration of a component in a mixture was explained by distribution of the particle size of components. With a small component, the larger number of particles in the same volume allowed them to surround the larger particles of the second component. These conclusions were confirmed by preparing mixtures with non-coloured components (Povidone-Eudragit, NaCl-Povidone, NaCl-Eudragit. Results again correlated with the ATR FTIR spectroscopy measurements. It was additionally shown that a small proportion of finer particles can drastically influence the surface of powder mixtures, due to their large contribution to the specific surface area. ATR FTIR is thus demonstrated to be a useful method for studying surfaces of powder mixtures also in terms of

  7. UPDATE ON MONOLITHIC FUEL FABRICATION METHODS

    SciTech Connect

    C. R. Clark; J. F. Jue; G. A. Moore; N. P. Hallinan; B. H. Park; D. E. Burkes

    2006-10-01

    Efforts to develop a viable monolithic research reactor fuel plate have continued at Idaho National Laboratory. These efforts have concentrated on both fabrication process refinement and scale-up to produce full sized fuel plates. Progress at INL has led to fabrication of hot isostatic pressed uranium-molybdenum bearing monolithic fuel plates. These miniplates are part of the RERTR-8 miniplate irradiation test. Further progress has also been made on friction stir weld processing which has been used to fabricate full size fuel plates which will be irradiated in the ATR and OSIRIS reactors.

  8. PHF11 promotes DSB resection, ATR signaling, and HR

    PubMed Central

    Gong, Yi; Handa, Naofumi; Kowalczykowski, Stephen C.; de Lange, Titia

    2017-01-01

    Resection of double-strand breaks (DSBs) plays a critical role in their detection and appropriate repair. The 3′ ssDNA protrusion formed through resection activates the ATR-dependent DNA damage response (DDR) and is required for DSB repair by homologous recombination (HR). Here we report that PHF11 (plant homeodomain finger 11) encodes a previously unknown DDR factor involved in 5′ end resection, ATR signaling, and HR. PHF11 was identified based on its association with deprotected telomeres and localized to sites of DNA damage in S phase. Depletion of PHF11 diminished the ATR signaling response to telomere dysfunction and genome-wide DNA damage, reduced end resection at sites of DNA damage, resulted in compromised HR and misrejoining of S-phase DSBs, and increased the sensitivity to DNA-damaging agents. PHF11 interacted with the ssDNA-binding protein RPA and was found in a complex with several nucleases, including the 5′ dsDNA exonuclease EXO1. Biochemical experiments demonstrated that PHF11 stimulates EXO1 by overcoming its inhibition by RPA, suggesting that PHF11 acts (in part) by promoting 5′ end resection at RPA-bound sites of DNA damage. These findings reveal a role for PHF11 in DSB resection, DNA damage signaling, and DSB repair. PMID:28115467

  9. Polynomial chaos theory for performance evaluation of ATR systems

    NASA Astrophysics Data System (ADS)

    DeVore, Michael D.; Bateman, Alec J.

    2010-04-01

    The development of a more unified theory of automatic target recognition (ATR) has received considerable attention over the last several years from individual researchers, working groups, and workshops. One of the major benefits expected to accrue from such a theory is an ability to analytically derive performance metrics that accurately predict real-world behavior. Numerous sources of uncertainty affect the actual performance of an ATR system, so direct calculation has been limited in practice to a few special cases because of the practical difficulties of manipulating arbitrary probability distributions over high dimensional spaces. This paper introduces an alternative approach for evaluating ATR performance based on a generalization of NorbertWiener's polynomial chaos theory. Through this theory, random quantities are expressed not in terms of joint distribution functions but as convergent orthogonal series over a shared random basis. This form can be used to represent any finite-variance distribution and can greatly simplify the propagation of uncertainties through complex systems and algorithms. The paper presents an overview of the relevant theory and, as an example application, a discussion of how it can be applied to model the distribution of position errors from target tracking algorithms.

  10. PHF11 promotes DSB resection, ATR signaling, and HR.

    PubMed

    Gong, Yi; Handa, Naofumi; Kowalczykowski, Stephen C; de Lange, Titia

    2017-01-01

    Resection of double-strand breaks (DSBs) plays a critical role in their detection and appropriate repair. The 3' ssDNA protrusion formed through resection activates the ATR-dependent DNA damage response (DDR) and is required for DSB repair by homologous recombination (HR). Here we report that PHF11 (plant homeodomain finger 11) encodes a previously unknown DDR factor involved in 5' end resection, ATR signaling, and HR. PHF11 was identified based on its association with deprotected telomeres and localized to sites of DNA damage in S phase. Depletion of PHF11 diminished the ATR signaling response to telomere dysfunction and genome-wide DNA damage, reduced end resection at sites of DNA damage, resulted in compromised HR and misrejoining of S-phase DSBs, and increased the sensitivity to DNA-damaging agents. PHF11 interacted with the ssDNA-binding protein RPA and was found in a complex with several nucleases, including the 5' dsDNA exonuclease EXO1. Biochemical experiments demonstrated that PHF11 stimulates EXO1 by overcoming its inhibition by RPA, suggesting that PHF11 acts (in part) by promoting 5' end resection at RPA-bound sites of DNA damage. These findings reveal a role for PHF11 in DSB resection, DNA damage signaling, and DSB repair.

  11. System issues of developing grayscale optical correlator for ATR applications

    NASA Astrophysics Data System (ADS)

    Chao, Tien-Hsin; Lu, Thomas

    2007-04-01

    We have been developing Grayscale Optical Correlator (GOC) and exploring a variety of automatic target recognition (ATR) applications to take advantage of the inherent performance advantages of the GOC parallel processing, high-speed, vast parallelism and high-speed [1-4]. To date, we have built compact 512 x 512, 1000 fps GOC systems and tested/demonstrated for field ATR experiments. We have also worked with our industrial partners to develop a 1024 x 1024 Ferroelectric Spatial Light Modulator (FLCSLM) to meet the challenging applications demanding larger input scene Field-of-View (FOV) and higher resolution. In this paper, two major system issues that we have encountered during the development efforts for real-world applications will be discussed. These include: 1) SLM dynamic range limitations and 2) ATR performance for CAD/CAC, computer-aided detection & classification (CAD/CAC) applications. Our simulation study has shown that the current 8-bit dynamic range possessed by the FLCSLM is adequate for both the input image and the correlation filter encodings. We will also describe the addition of a neural network (NN) post-processor to greatly decrease the false positive detection rate while retaining the high positive detection rate obtained by the by the GOC. Experimental results demonstrating the high-performance of the fused GOC and NN processor will be provided.

  12. Simulator of IRST system with ATR embedded functions

    NASA Astrophysics Data System (ADS)

    Sozzi, B.; Fossati, E.; Barani, G.; Santini, N.; Ondini, A.; Colombi, G.; Quaranta, C.

    2010-04-01

    This paper presents a soft-real time simulator for IRST (InfraRed Search and Track) systems with ATR (Automatic Target Recognition) embedded functions to test airborne applications performance. The IR camera model includes detector, optics, available Field-of-Regard, etc., and it is integrated with the motion platform local stabilization system to consider all factors impacting IR images. The atmosphere contributions are taken into account by means of a link to ModTran computer program. Sensor simulation allows derivation and assessment of IR Figures of Merit (NEI, NETD, SNR...). IR signatures of targets derive both from data collected in specific trial campaigns and from laboratory built models. The simulation of the scan procedure takes into account different policies (ground points paths or defined angular volume) and different platform motion strategies (continuous or step steering scan). The scan process includes Kalman technique to face unexpected variations of aircraft motion. Track and ATR processors are simulated and run consistently on the output of the sensor model. The simulator functions are developed in MatLab and SIMULINK and then exported in C code to be integrated in soft real-time environment. The use of this simulator supports the definition and design of the IRST systems especially for the evaluation of the most demanding operative requirements. An application of this simulator is for the NEURON UCAV (Unmanned Combat Air Vehicle) technological demonstrator, which accommodates on board both IRST and ATR tasks.

  13. Clipping service: ATR-based SAR image compression

    NASA Astrophysics Data System (ADS)

    Rodkey, David L.; Welby, Stephen P.; Hostetler, Larry D.

    1996-06-01

    Future wide area surveillance systems such as the Tier II+ and Tier III- unmanned aerial vehicles (UAVs) will be gathering cast amounts of high resolution SAR data for transmission to ground stations and subsequent analysis by image interpreters to provide critical and timely information to field commanders. This extremely high data rate presents two problems. First, wide bandwidth data link channels which would be needed to transmit this high data rate presents two problems. First, wide bandwidth data link channels which would be needed to transmit this imagery to a ground station are both expensive and difficult to obtain. Second, the volume of data which is generated by the system will quickly saturate any human-based analysis system without some degree of computer assistance. The ARPA sponsored clipping service program seeks to apply automatic target recognition (ATR) technology to perform 'intelligent' data compression on this imagery in a way which will provide a product on the ground that preserves essential information for further processing either by the military analyst or by a ground-based ATR system. An ATR system on board the UAV would examine the imagery data stream in real time determining regions of interest. Imagery from those regions would be transmitted to the ground in a manner which preserved most or all of the information contained in the original image. The remainder of the imagery would be transmitted to the ground with lesser fidelity. This paper presents system analysis deriving the operational requirements for the clipping service system and examines candidate architectures.

  14. Transcriptional regulation of the daptomycin gene cluster in Streptomyces roseosporus by an autoregulator, AtrA.

    PubMed

    Mao, Xu-Ming; Luo, Shuai; Zhou, Ri-Cheng; Wang, Feng; Yu, Pin; Sun, Ning; Chen, Xiao-Xia; Tang, Yi; Li, Yong-Quan

    2015-03-20

    Daptomycin is a cyclic lipopeptide antibiotic produced by Streptomyces roseosporus. To reveal the transcriptional regulatory mechanism of daptomycin biosynthesis, we used the biotinylated dptE promoter (dptEp) as a probe to affinity isolate the dptEp-interactive protein AtrA, a TetR family transcriptional regulator, from the proteome of mycelia. AtrA bound directly to dptEp to positively regulate gene cluster expression and daptomycin production. Meanwhile, both ΔatrA and ΔadpA mutants showed bald phenotype and null production of daptomycin. AdpA positively regulated atrA expression by direct interaction with atrA promoter (atrAp), and removal of ArpA in S. roseosporus, a homolog of the A-factor receptor, resulted in accelerated morphological development and increased daptomycin production, suggesting that atrA was the target of AdpA to mediate the A-factor signaling pathway. Furthermore, AtrA was positively autoregulated by binding to its own promoter atrAp. Thus, for the first time at the transcriptional level, we have identified an autoregulator, AtrA, that directly mediates the A-factor signaling pathway to regulate the proper production of daptomycin.

  15. SUMOylation of ATRIP potentiates DNA damage signaling by boosting multiple protein interactions in the ATR pathway.

    PubMed

    Wu, Ching-Shyi; Ouyang, Jian; Mori, Eiichiro; Nguyen, Hai Dang; Maréchal, Alexandre; Hallet, Alexander; Chen, David J; Zou, Lee

    2014-07-01

    The ATR (ATM [ataxia telangiectasia-mutated]- and Rad3-related) checkpoint is a crucial DNA damage signaling pathway. While the ATR pathway is known to transmit DNA damage signals through the ATR-Chk1 kinase cascade, whether post-translational modifications other than phosphorylation are important for this pathway remains largely unknown. Here, we show that protein SUMOylation plays a key role in the ATR pathway. ATRIP, the regulatory partner of ATR, is modified by SUMO2/3 at K234 and K289. An ATRIP mutant lacking the SUMOylation sites fails to localize to DNA damage and support ATR activation efficiently. Surprisingly, the ATRIP SUMOylation mutant is compromised in the interaction with a protein group, rather than a single protein, in the ATR pathway. Multiple ATRIP-interacting proteins, including ATR, RPA70, TopBP1, and the MRE11-RAD50-NBS1 complex, exhibit reduced binding to the ATRIP SUMOylation mutant in cells and display affinity for SUMO2 chains in vitro, suggesting that they bind not only ATRIP but also SUMO. Fusion of a SUMO2 chain to the ATRIP SUMOylation mutant enhances its interaction with the protein group and partially suppresses its localization and functional defects, revealing that ATRIP SUMOylation promotes ATR activation by providing a unique type of protein glue that boosts multiple protein interactions along the ATR pathway. © 2014 Wu et al.; Published by Cold Spring Harbor Laboratory Press.

  16. ATR Plays a Direct Antiapoptotic Role at Mitochondria, which Is Regulated by Prolyl Isomerase Pin1.

    PubMed

    Hilton, Benjamin A; Li, Zhengke; Musich, Phillip R; Wang, Hui; Cartwright, Brian M; Serrano, Moises; Zhou, Xiao Zhen; Lu, Kun Ping; Zou, Yue

    2015-10-01

    ATR, a PI3K-like protein kinase, plays a key role in regulating DNA damage responses. Its nuclear checkpoint kinase function is well documented, but little is known about its function outside the nucleus. Here we report that ATR has an antiapoptotic activity at mitochondria in response to UV damage, and this activity is independent of its hallmark checkpoint/kinase activity and partner ATRIP. ATR contains a BH3-like domain that allows ATR-tBid interaction at mitochondria, suppressing cytochrome c release and apoptosis. This mitochondrial activity of ATR is downregulated by Pin1 that isomerizes ATR from cis-isomer to trans-isomer at the phosphorylated Ser428-Pro429 motif. However, UV inactivates Pin1 via DAPK1, stabilizing the pro-survival cis-isomeric ATR. In contrast, nuclear ATR remains in the trans-isoform disregarding UV. This cytoplasmic response of ATR may provide a mechanism for the observed antiapoptotic role of ATR in suppressing carcinogenesis and its inhibition in sensitizing anticancer agents for killing of cancer cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Advanced Test Reactor National Scientific User Facility (ATR NSUF) Monthly Report October 2014

    SciTech Connect

    Ogden, Dan

    2014-10-01

    Advanced Test Reactor National Scientific User Facility (ATR NSUF) Monthly Report October 2014 Highlights • Rory Kennedy, Dan Ogden and Brenden Heidrich traveled to Germantown October 6-7, for a review of the Infrastructure Management mission with Shane Johnson, Mike Worley, Bradley Williams and Alison Hahn from NE-4 and Mary McCune from NE-3. Heidrich briefed the group on the project progress from July to October 2014 as well as the planned path forward for FY15. • Jim Cole gave two invited university seminars at Ohio State University and University of Florida, providing an overview of NSUF including available capabilities and the process for accessing facilities through the peer reviewed proposal process. • Jim Cole and Rory Kennedy co-chaired the NuMat meeting with Todd Allen. The meeting, sponsored by Elsevier publishing, was held in Clearwater, Florida, and is considered one of the premier nuclear fuels and materials conferences. Over 340 delegates attended with 160 oral and over 200 posters presented over 4 days. • Thirty-one pre-applications were submitted for NSUF access through the NE-4 Combined Innovative Nuclear Research Funding Opportunity Announcement. • Fourteen proposals were received for the NSUF Rapid Turnaround Experiment Summer 2014 call. Proposal evaluations are underway. • John Jackson and Rory Kennedy attended the Nuclear Fuels Industry Research meeting. Jackson presented an overview of ongoing NSUF industry research.

  18. 10 CFR 830 Major Modification Determination for Advanced Test Reactor LEU Fuel Conversion

    SciTech Connect

    Boyd D. Christensen; Michael A. Lehto; Noel R. Duckwitz

    2012-05-01

    The Advanced Test Reactor (ATR), located in the ATR Complex of the Idaho National Laboratory (INL), was constructed in the 1960s for the purpose of irradiating reactor fuels and materials. Other irradiation services, such as radioisotope production, are also performed at ATR. The ATR is fueled with high-enriched uranium (HEU) matrix (UAlx) in an aluminum sandwich plate cladding. The National Nuclear Security Administration Global Threat Reduction Initiative (GTRI) strategic mission includes efforts to reduce and protect vulnerable nuclear and radiological material at civilian sites around the world. Converting research reactors from using HEU to low-enriched uranium (LEU) was originally started in 1978 as the Reduced Enrichment for Research and Test Reactors (RERTR) Program under the U.S. Department of Energy (DOE) Office of Science. Within this strategic mission, GTRI has three goals that provide a comprehensive approach to achieving this mission: The first goal, the driver for the modification that is the subject of this determination, is to convert research reactors from using HEU to LEU. Thus the mission of the ATR LEU Fuel Conversion Project is to convert the ATR and Advanced Test Reactor Critical facility (ATRC) (two of the six U.S. High-Performance Research Reactors [HPRR]) to LEU fuel by 2017. The major modification criteria evaluation of the project pre-conceptual design identified several issues that lead to the conclusion that the project is a major modification.

  19. Assessment of Nuclear Fuels using Radiographic Thickness Measurement Method

    SciTech Connect

    Muhammad Abir; Fahima Islam; Hyoung Koo Lee; Daniel Wachs

    2014-11-01

    The Convert branch of the National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI) focuses on the development of high uranium density fuels for research and test reactors for nonproliferation. This fuel is aimed to convert low density high enriched uranium (HEU) based fuel to high density low enriched uranium (LEU) based fuel for high performance research reactors (HPRR). There are five U.S. reactors that fall under the HPRR category, including: the Massachusetts Institute of Technology Reactor (MITR), the National Bureau of Standards Reactor (NBSR), the Missouri University Research Reactor (UMRR), the Advanced Test Reactor (ATR), and the High Flux Isotope Reactor (HFIR). U-Mo alloy fuel phase in the form of either monolithic or dispersion foil type fuels, such as ATR Full-size In center flux trap Position (AFIP) and Reduced Enrichment for Research and Test Reactor (RERTR), are being designed for this purpose. The fabrication process1 of RERTR is susceptible to introducing a variety of fuel defects. A dependable quality control method is required during fabrication of RERTR miniplates to maintain the allowable design tolerances, therefore evaluating and analytically verifying the fabricated miniplates for maintaining quality standards as well as safety. The purpose of this work is to analyze the thickness of the fabricated RERTR-12 miniplates using non-destructive technique to meet the fuel plate specification for RERTR fuel to be used in the ATR.

  20. ATR signaling can drive cells into senescence in the absence of DNA breaks

    PubMed Central

    Toledo, Luis I.; Murga, Matilde; Gutierrez-Martinez, Paula; Soria, Rebeca; Fernandez-Capetillo, Oscar

    2008-01-01

    The ATR kinase is a key transducer of “replicative stress,” the type of genomic damage that has been postulated to be induced by oncogenes. Here we describe a cellular system in which we can unleash ATR activity at will, in the absence of any actual damage or additional signaling pathways triggered by DNA breaks. We demonstrate that activating ATR is sufficient to promote cell cycle arrest and, if persistent, triggers p53-dependent but Ink4a/ARF-independent senescence. Moreover, we show that an ectopic activation of ATR leads to a G1/S arrest in ATM−/− cells, providing the first evidence of functional complementation of ATM deficiency by ATR. Our system provides a novel platform for the study of the specific functions of ATR signaling and adds evidence for the tumor-suppressive potential of the DNA damage response. PMID:18245444

  1. Fuel flexible fuel injector

    DOEpatents

    Tuthill, Richard S; Davis, Dustin W; Dai, Zhongtao

    2015-02-03

    A disclosed fuel injector provides mixing of fuel with airflow by surrounding a swirled fuel flow with first and second swirled airflows that ensures mixing prior to or upon entering the combustion chamber. Fuel tubes produce a central fuel flow along with a central airflow through a plurality of openings to generate the high velocity fuel/air mixture along the axis of the fuel injector in addition to the swirled fuel/air mixture.

  2. Extended life aluminide fuel. Final report

    SciTech Connect

    Miller, L.G.; Beeston, J.M.

    1986-06-01

    As the price of fuel fabrication, shipment of both new and spent fuel, and fuel reprocessing continue to rise at a rapid rate, researchers look for alternate methods to keep reactor fuel costs within their limited funding. Extended fuel element lifetimes, without jeopardizing reactor safety, can reduce fuel costs by up to a factor of two. The Extended Life Aluminide (ELAF) program was started at the Idaho National Engineering Laboratory (INEL) as a joint project of the United States Department of Energy (DOE), the University of Missouri, and the Massachusetts Institute of Technology research reactors. Fuel plates of Advanced Test Reactor (ATR) type construction were fabricated at Atomics International and irradiated in the ATR at the INEL. Four fuel matrix compositions were tested (i.e., 50 vol% UAl/sub x/ cores for reference, and 40, 45 and 50 vol% UAl/sub 2/ cores). The 50 vol% UAl/sub 2/ cores contained up to 3 grams U-235 per cm/sup 3/ of core. Three plates of each composition were irradiated to peak burnup levels of 3 x 10/sup 21/ fission/cm/sup 3/ of core. The only observed damage was due to external corrosion at similar rates experienced by UAl/sub x/ fuel elements in test reactors.

  3. Selective killing of ATM- or p53-deficient cancer cells through inhibition of ATR.

    PubMed

    Reaper, Philip M; Griffiths, Matthew R; Long, Joanna M; Charrier, Jean-Damien; Maccormick, Somhairle; Charlton, Peter A; Golec, Julian M C; Pollard, John R

    2011-04-13

    Here we report a comprehensive biological characterization of a potent and selective small-molecule inhibitor of the DNA damage response (DDR) kinase ATR. We show a profound synthetic lethal interaction between ATR and the ATM-p53 tumor suppressor pathway in cells treated with DNA-damaging agents and establish ATR inhibition as a way to transform the outcome for patients with cancer treated with ionizing radiation or genotoxic drugs.

  4. Status report of the ATR SPING-3A and detailed calibration guideline

    SciTech Connect

    Koeppen, L.D.; Rogers, J.W.

    1985-12-01

    The Radiation Measurements Laboratory (RML) onducted testing and an evaluation of the ATR SPING-3 after installation of the new ''A'' series software (firmware) and retrofit kit. The purpose of this report is to provide the ATR SPING-3A users with a document describing the present status of the unit, how the system was tested, a suggested calibration guideline, how the system should be operated for the ATR application, and why it should be used in this manner.

  5. Distillate fuel-oil processing for phosphoric acid fuel-cell power plants

    SciTech Connect

    Ushiba, K. K.

    1980-02-01

    The current efforts to develop distillate oil-steam reforming processes are reviewed, and the applicability of these processes for integration with the fuel cell are discussed. The development efforts can be grouped into the following processing approaches: high-temperature steam reforming (HTSR); autothermal reforming (ATR); autothermal gasification (AG); and ultra desulfurization followed by steam reforming. Sulfur in the feed is a key problem in the process development. A majority of the developers consider sulfur as an unavoidable contaminant of distillate fuel and are aiming to cope with it by making the process sulfur-tolerant. In the HTSR development, the calcium aluminate catalyst developed by Toyo Engineering represents the state of the art. United Technology (UTC), Engelhard, and Jet Propulsion Laboratory (JPL) are also involved in the HTSR research. The ATR of distillate fuel is investigated by UTC and JPL. The autothermal gasification (AG) of distillate fuel is being investigated by Engelhard and Siemens AG. As in the ATR, the fuel is catalytically gasified utilizing the heat generated by in situ partial combustion of feed, however, the goal of the AG is to accomplish the initial breakdown of the feed into light gases and not to achieve complete conversion to CO and H/sub 2/. For the fuel-cell integration, a secondary reforming of the light gases from the AG step is required. Engelhard is currently testing a system in which the effluent from the AG section enters the steam-reforming section, all housed in a single vessel. (WHK)

  6. EVALUATION OF CORE PHYSICS ANALYSIS METHODS FOR CONVERSION OF THE INL ADVANCED TEST REACTOR TO LOW-ENRICHMENT FUEL

    SciTech Connect

    Mark DeHart; Gray S. Chang

    2012-04-01

    Computational neutronics studies to support the possible conversion of the ATR to LEU are underway. Simultaneously, INL is engaged in a physics methods upgrade project to put into place modern computational neutronics tools for future support of ATR fuel cycle and experiment analysis. A number of experimental measurements have been performed in the ATRC in support of the methods upgrade project, and are being used to validate the new core physics methods. The current computational neutronics work is focused on performance of scoping calculations for the ATR core loaded with a candidate LEU fuel design. This will serve as independent confirmation of analyses that have been performed previously, and will evaluate some of the new computational methods for analysis of a candidate LEU fuel for ATR.

  7. ATR cooperates with CTC1 and STN1 to maintain telomeres and genome integrity in Arabidopsis.

    PubMed

    Boltz, Kara A; Leehy, Katherine; Song, Xiangyu; Nelson, Andrew D; Shippen, Dorothy E

    2012-04-01

    The CTC1/STN1/TEN1 (CST) complex is an essential constituent of plant and vertebrate telomeres. Here we show that CST and ATR (ataxia telangiectasia mutated [ATM] and Rad3-related) act synergistically to maintain telomere length and genome stability in Arabidopsis. Inactivation of ATR, but not ATM, temporarily rescued severe morphological phenotypes associated with ctc1 or stn1. Unexpectedly, telomere shortening accelerated in plants lacking CST and ATR. In first-generation (G1) ctc1 atr mutants, enhanced telomere attrition was modest, but in G2 ctc1 atr, telomeres shortened precipitously, and this loss coincided with a dramatic decrease in telomerase activity in G2 atr mutants. Zeocin treatment also triggered a reduction in telomerase activity, suggesting that the prolonged absence of ATR leads to a hitherto-unrecognized DNA damage response (DDR). Finally, our data indicate that ATR modulates DDR in CST mutants by limiting chromosome fusions and transcription of DNA repair genes and also by promoting programmed cell death in stem cells. We conclude that the absence of CST in Arabidopsis triggers a multifaceted ATR-dependent response to facilitate maintenance of critically shortened telomeres and eliminate cells with severe telomere dysfunction.

  8. Requirement of ATR for maintenance of intestinal stem cells in aging Drosophila.

    PubMed

    Park, Joung-Sun; Na, Hyun-Jin; Pyo, Jung-Hoon; Jeon, Ho-Jun; Kim, Young-Shin; Yoo, Mi-Ae

    2015-05-01

    The stem cell genomic stability forms the basis for robust tissue homeostasis, particularly in high-turnover tissues. For the genomic stability, DNA damage response (DDR) is essential. This study was focused on the role of two major DDR-related factors, ataxia telangiectasia-mutated (ATM) and ATM- and RAD3-related (ATR) kinases, in the maintenance of intestinal stem cells (ISCs) in the adultDrosophila midgut. We explored the role of ATM and ATR, utilizing immunostaining with an anti-pS/TQ antibody as an indicator of ATM/ATR activation, γ-irradiation as a DNA damage inducer, and the UAS/GAL4 system for cell type-specific knockdown of ATM, ATR, or both during adulthood. The results showed that the pS/TQ signals got stronger with age and after oxidative stress. The pS/TQ signals were found to be more dependent on ATR rather than on ATM in ISCs/enteroblasts (EBs). Furthermore, an ISC/EB-specific knockdown of ATR, ATM, or both decreased the number of ISCs and oxidative stress-induced ISC proliferation. The phenotypic changes that were caused by the ATR knockdown were more pronounced than those caused by the ATM knockdown; however, our data indicate that ATR and ATM are both needed for ISC maintenance and proliferation; ATR seems to play a bigger role than does ATM.

  9. Drop-in capsule testing of plutonium-based fuels in the Advanced Test Reactor

    SciTech Connect

    Chang, G.S.; Ryskamp, J.M.; Terry, W.K.; Ambrosek, R.G.; Palmer, A.J.; Roesener, R.A.

    1996-09-01

    The most attractive way to dispose of weapons-grade plutonium (WGPu) is to use it as fuel in existing light water reactors (LWRs) in the form of mixed oxide (MOX) fuel - i.e., plutonia (PuO[sub 2]) mixed with urania (UO[sub 2]). Before U.S. reactors could be used for this purpose, their operating licenses would have to be amended. Numerous technical issues must be resolved before LWR operating licenses can be amended to allow the use of MOX fuel. The proposed weapons-grade MOX fuel is unusual, even relative to ongoing foreign experience with reactor-grade MOX power reactor fuel. Some demonstration of the in- reactor thermal, mechanical, and fission gas release behavior of the prototype fuel will most likely be required in a limited number of test reactor irradiations. The application to license operation with MOX fuel must be amply supported by experimental data. The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL) is capable of playing a key role in the irradiation, development, and licensing of these new fuel types. The ATR is a 250- MW (thermal) LWR designed to study the effects of intense radiation on reactor fuels and materials. For 25 years, the primary role of the ATR has been to serve in experimental investigations for the development of advanced nuclear fuels. Both large- and small-volume test positions in the ATR could be used for MOX fuel irradiation. The ATR would be a nearly ideal test bed for developing data needed to support applications to license LWRs for operation with MOX fuel made from weapons-grade plutonium. Furthermore, these data can be obtained more quickly by using ATR instead of testing in a commercial LWR. Our previous work in this area has demonstrated that it is technically feasible to perform MOX fuel testing in the ATR. This report documents our analyses of sealed drop-in capsules containing plutonium-based test specimens placed in various ATR positions.

  10. Electromagnetic model based SAR ATR through attributed scatterers

    NASA Astrophysics Data System (ADS)

    Ma, Conghui; Wen, Gongjian; Gao, Feng; Huang, Xiaohong; Yang, Xiaoliang

    2016-10-01

    Electromagnetic model (em-model) provides a concise and physically relevant description of target through representative scatterers. In a forward built em-model, detailed information about each scatterer's position, scattering amplitude along with its provenance can be predicted. This makes em-model a good candidate for use in synthetic aperture radar (SAR) automatic target recognition (ATR). In this paper, we introduce scatterers' provenance as attributed information into target recognition, and an attributed em-model based target recognition method is proposed. Firstly, according to the purpose of ATR, each scatterer in em-model is endowed with an importance factor based on its provenance. Secondly, a detection is implemented to decide whether the em-model predicted scatterer has a corresponding scatterer in measured data. If the scatterer exist in measured target, evaluate how similar the scatterer pair resembled with each other. Next, similarities of all the scatterer pairs are synthesized as a whole match score between em-model and SAR data. In the synthesis, the importance factor servers as a weighting factor that scatterer with more attention will be more discriminative for recognition. In the end, target in measured SAR data is recognized as the model type or not based on the match score. The novelty of this method comes from taking into account of the provenance information of scatterers as attributed information and endowing the scatterers with different important factors according to their importance in recognition. This makes the attributed scatterer based recognition method pertinent to the purpose of ATR. Experiments on simulated Tank SAR data that produced by a high frequency electromagnetic simulation software verified the effectiveness of this method.

  11. UCSB ATR-­NSUF Irradiation DMC Sample Inspection Report

    SciTech Connect

    Saleh, Tarik A.; Quintana, Matthew Estevan; Romero, Tobias J.

    2015-02-23

    A variety of tensile samples of Ferritic and Oxide Dispersion Strengthened (ODS or nanoferritic) steels were placed the ATR reactor over 2 Years achieving doses of roughly 4-6 dpa at temperatures of roughly 290°C. After irradiation, samples were shipped from the MFC hot cells at Idaho National Laboratory (INL) to the Wing 9 hot cells in the CMR facility at Los Alamos National Laboratory. Samples were cleaned to removed alpha contamination from the MFC hot cells, and then, as needed removed from their irradiation containers, sorted and inspected. This report will summarize the inspection of the Disc Multipurpose Coupon (DMC) inspection from packet 7-1.

  12. Enhanced Accident Tolerant LWR Fuels: Metrics Development

    SciTech Connect

    Shannon Bragg-Sitton; Lori Braase; Rose Montgomery; Chris Stanek; Robert Montgomery; Lance Snead; Larry Ott; Mike Billone

    2013-09-01

    The Department of Energy (DOE) Fuel Cycle Research and Development (FCRD) Advanced Fuels Campaign (AFC) is conducting research and development on enhanced Accident Tolerant Fuels (ATF) for light water reactors (LWRs). This mission emphasizes the development of novel fuel and cladding concepts to replace the current zirconium alloy-uranium dioxide (UO2) fuel system. The overall mission of the ATF research is to develop advanced fuels/cladding with improved performance, reliability and safety characteristics during normal operations and accident conditions, while minimizing waste generation. The initial effort will focus on implementation in operating reactors or reactors with design certifications. To initiate the development of quantitative metrics for ATR, a LWR Enhanced Accident Tolerant Fuels Metrics Development Workshop was held in October 2012 in Germantown, MD. This paper summarizes the outcome of that workshop and the current status of metrics development for LWR ATF.

  13. Monte Carlo minicell approach for a detailed MOX fuel-pin power profile analysis

    SciTech Connect

    Chang, G.S.; Ryskamp, J.M.

    1997-12-01

    The U.S. Department of Energy (DOE) is pursuing two options to dispose of surplus weapons-grade plutonium (WGPu). One option is to burn the WGPu in a mixed-oxide (MOX) fuel form in light water reactors (LWRs). A significant challenge is to demonstrate that the differences between the WG and reactor-grade (RG) MOX fuel are minimal, and therefore, the commercial MOX experience base is applicable. MOX fuel will be irradiated in the Advanced Test Reactor (ATR) to investigate this assertion. Detailed power distributions throughout the MOX pins are required to determine temperature distributions. The purpose of this work is to develop a new Monte Carlo procedure for accurately determining power distributions in fuel pins located in the ATR reflector. Conventional LWR methods are not appropriate because of the unique ATR geometry.

  14. ATR1, a Saccharomyces cerevisiae gene encoding a transmembrane protein required for aminotriazole resistance.

    PubMed Central

    Kanazawa, S; Driscoll, M; Struhl, K

    1988-01-01

    In Saccharomyces cerevisiae, 3-amino-1,2,4-triazole (aminotriazole) competitively inhibits the activity of imidazoleglycerolphosphate dehydratase, the product of the HIS3 gene. Wild-type strains are able to grow in the presence of 10 mM aminotriazole because they induce the level of imidazoleglycerolphosphate dehydratase. However, strains containing gcn4 mutations are unable to grow in medium containing aminotriazole because they lack the GCN4 transcriptional activator protein necessary for the coordinate induction of HIS3 and other amino acid biosynthetic genes. Here, we isolated a new gene, designated ATR1, which when present in multiple copies per cell allowed gcn4 mutant strains to grow in the presence of aminotriazole. In wild-type strains, multiple copies of ATR1 permitted growth at extremely high concentrations of aminotriazole (80 mM), whereas a chromosomal deletion of ATR1 caused growth inhibition at very low concentrations (5 mM). When radioactive aminotriazole was added exogenously, cells with multiple copies of ATR1 accumulated less aminotriazole than wild-type cells, whereas cells with the atr1 deletion mutation retained more aminotriazole. Unlike the mammalian mdr or yeast PDR genes that confer resistance to many drugs, ATR1 appears to confer resistance only to aminotriazole. Genetic analysis, mRNA mapping, and DNA sequencing revealed that (i) the primary translation product of ATR1 contains 547 amino acids, (ii) ATR1 transcription is induced by aminotriazole, and (iii) the ATR1 promoter region contains a binding site for the GCN4 activator protein. The deduced amino acid sequence suggests that ATR1 protein is very hydrophobic with many membrane-spanning regions, has several potential glycosylation sites, and may contain an ATP-binding site. We suggest that ATR1 encodes a membrane-associated component of the machinery responsible for pumping aminotriazole (and possibly other toxic compounds) out of the cell. Images PMID:3280970

  15. Open source tools for ATR development and performance evaluation

    NASA Astrophysics Data System (ADS)

    Baumann, James M.; Dilsavor, Ronald L.; Stubbles, James; Mossing, John C.

    2002-07-01

    Early in almost every engineering project, a decision must be made about tools; should I buy off-the-shelf tools or should I develop my own. Either choice can involve significant cost and risk. Off-the-shelf tools may be readily available, but they can be expensive to purchase and to maintain licenses, and may not be flexible enough to satisfy all project requirements. On the other hand, developing new tools permits great flexibility, but it can be time- (and budget-) consuming, and the end product still may not work as intended. Open source software has the advantages of both approaches without many of the pitfalls. This paper examines the concept of open source software, including its history, unique culture, and informal yet closely followed conventions. These characteristics influence the quality and quantity of software available, and ultimately its suitability for serious ATR development work. We give an example where Python, an open source scripting language, and OpenEV, a viewing and analysis tool for geospatial data, have been incorporated into ATR performance evaluation projects. While this case highlights the successful use of open source tools, we also offer important insight into risks associated with this approach.

  16. ATR-FTIR Spectroscopy in the Undergraduate Chemistry Laboratory: Part I--Fundamentals and Examples

    ERIC Educational Resources Information Center

    Schuttlefield, Jennifer D.; Grassian, Vicki H.

    2008-01-01

    Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is a useful technique for measuring the infrared spectra of solids and liquids as well as probing adsorption on particle surfaces. Several examples of the use of FTIR-ATR spectroscopy in different undergraduate chemistry laboratory courses are presented here. These…

  17. ATR-FTIR Spectroscopy in the Undergraduate Chemistry Laboratory: Part I--Fundamentals and Examples

    ERIC Educational Resources Information Center

    Schuttlefield, Jennifer D.; Grassian, Vicki H.

    2008-01-01

    Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is a useful technique for measuring the infrared spectra of solids and liquids as well as probing adsorption on particle surfaces. Several examples of the use of FTIR-ATR spectroscopy in different undergraduate chemistry laboratory courses are presented here. These…

  18. 30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Automated Temporary Roof Support (ATRS) systems... COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.209 Automated Temporary Roof Support (ATRS) systems. (a) Except in anthracite mines and as specified...

  19. 30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Automated Temporary Roof Support (ATRS) systems... COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.209 Automated Temporary Roof Support (ATRS) systems. (a) Except in anthracite mines and as specified...

  20. ATR acts stage specifically to regulate multiple aspects of mammalian meiotic silencing.

    PubMed

    Royo, Hélène; Prosser, Haydn; Ruzankina, Yaroslava; Mahadevaiah, Shantha K; Cloutier, Jeffrey M; Baumann, Marek; Fukuda, Tomoyuki; Höög, Christer; Tóth, Attila; de Rooij, Dirk G; Bradley, Allan; Brown, Eric J; Turner, James M A

    2013-07-01

    In mammals, homologs that fail to synapse during meiosis are transcriptionally inactivated. This process, meiotic silencing, drives inactivation of the heterologous XY bivalent in male germ cells (meiotic sex chromosome inactivation [MSCI]) and is thought to act as a meiotic surveillance mechanism. The checkpoint protein ATM and Rad3-related (ATR) localizes to unsynapsed chromosomes, but its role in the initiation and maintenance of meiotic silencing is unknown. Here we show that ATR has multiple roles in silencing. ATR first regulates HORMA (Hop1, Rev7, and Mad2) domain protein HORMAD1/2 phosphorylation and localization of breast cancer I (BRCA1) and ATR cofactors ATR-interacting peptide (ATRIP)/topoisomerase 2-binding protein 1 (TOPBP1) at unsynapsed axes. Later, it acts as an adaptor, transducing signaling at unsynapsed axes into surrounding chromatin in a manner that requires interdependence with mediator of DNA damage checkpoint 1 (MDC1) and H2AFX. Finally, ATR catalyzes histone H2AFX phosphorylation, the epigenetic event leading to gene inactivation. Using a novel genetic strategy in which MSCI is used to silence a chosen gene in pachytene, we show that ATR depletion does not disrupt the maintenance of silencing and that silencing comprises two phases: The first is dynamic and reversible, and the second is stable and irreversible. Our work identifies a role for ATR in the epigenetic regulation of gene expression and presents a new technique for ablating gene function in the germline.

  1. Mixed oxide fuel testing capabilities in the Advanced Test Reactor

    SciTech Connect

    Ryskamp, J.M.; Sterbentz, J.W.; Chang, G.S.; Terry, W.K.

    1996-08-01

    The most attractive way to dispose of weapons-grade Plutonium (WGPu) is to use WGPu as fuel in existing light water reactors (LWRs) in the form of mixed oxide (MOX) fuel--i.e., plutonia (PuO{sub 2}) mixed with urania (UO{sub 2}). Before US reactors could be used for this purpose, their operating licenses would have to be amended. Numerous technical issues must be resolved before LWR operating licenses can be amended to allow the use of MOX fuel. The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL) possesses many advantages for performing tests to resolve most of the issues. It has ample core test volume, high neutron flux, test loops with cooling systems independent of the core coolant, and extensive support facilities. The ATR can deliver a neutron flux of appropriate intensity and energy distribution to the MOX test specimens while simultaneously accommodating test requirements for other programs. The authors have performed calculations to show that the use of hafnium shrouds can produce spectrum adjustments that will bring the flux spectrum in ATR test loops into a good approximation to the spectrum anticipated in a commercial LWR containing MOX fuel while allowing operation of the test fuel assemblies near their design values of linear heat generation rate. The ATR would be a nearly ideal test bed for developing data needed to support applications to license LWRs for operation with MOX fuel made from weapons-grade plutonium. Furthermore, this data can be obtained more quickly by using ATR instead of testing in a commercial LWR.

  2. Quantitative monitoring of membrane permeation via in-situ ATR FT-IR spectroscopy

    NASA Astrophysics Data System (ADS)

    Beckingham, Bryan; Miller, Daniel

    Ion conducting membranes are of interest for various energy applications including fuel cells and artificial photosynthesis systems. Within the context of artificial photosynthesis, membranes are desired that facilitate the ion transport necessary to feed the electrochemical reactions while meeting various additional selectivity and permeability demands depending on the CO2 reduction products. Herein, we demonstrate the use of in-situ ATR FT-IR spectroscopy to quantitatively resolve the concentration of single and multicomponent mixtures of various CO2 reduction products including methanol, formate and acetate. We then apply this methodology to the in-situ monitoring of the permeation of single and multicomponent mixtures across commercially available membranes. Membrane permeabilities and selectivities calculated from the single component time-resolved concentration curves are compared to the multicomponent permeation experiments. This material is based upon work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC000493.

  3. AGR-3/4 Data Qualification Report for ATR Cycles 151A, 151B, 152A, 152B, 154A, and 154B

    SciTech Connect

    Binh T. Pham

    2014-02-01

    This data report provides the qualification status of Advanced Gas Reactor-3/4 (AGR-3/4) fuel irradiation experimental data from Advanced Test Reactor (ATR) Cycles 151A, 151B, 152A, 152B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Of these cycles, ATR Cycle 152A is a low power cycle that occurred when the ATR core was briefly at low power. The irradiation data are not used for physics and thermal calculation, but the qualification status of these cycle data is still covered in this report. On the other hand, during ATR Cycles 153A (unplanned Outage cycle) and 153B (Power Axial Locator Mechanism [PALM] cycle), the AGR-3/4 was pulled out from the ATR core and stored in the canal to avoid being overheated. Therefore, qualification of the AGR-3/4 irradiation data from these 2 cycles was excluded in this report. By the end of ATR Cycle 154B, AGR-3/4 was irradiated for a total of 264.1 effective full power days. The AGR-3/4 data streams addressed in this report include thermocouple (TC) temperatures, sweep gas data (flow rates, pressure, and moisture content), and Fission Product Monitoring System (FPMS) data (release rates and release-to-birth rate ratios [R/Bs]) for each of the twelve capsules in the AGR-3/4 experiment. The final data qualification status for these data streams is determined by a Data Review Committee (DRC) composed of AGR technical leads, Sitewide Quality Assurance (QA), and NDMAS analysts. The DRC convened on February 12, 2014, reviewed the data acquisition process, and considered whether the data met the requirements for data collection as specified in QA-approved Very High Temperature Reactor (VHTR) Technology Development Office (TDO) data collection plans. The DRC also examined the results of NDMAS data testing and statistical analyses, and confirmed the qualification status of the data as given in this report.

  4. Self-sustained operation of a kW e-class kerosene-reforming processor for solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Yoon, Sangho; Bae, Joongmyeon; Kim, Sunyoung; Yoo, Young-Sung

    In this paper, fuel-processing technologies are developed for application in residential power generation (RPG) in solid oxide fuel cells (SOFCs). Kerosene is selected as the fuel because of its high hydrogen density and because of the established infrastructure that already exists in South Korea. A kerosene fuel processor with two different reaction stages, autothermal reforming (ATR) and adsorptive desulfurization reactions, is developed for SOFC operations. ATR is suited to the reforming of liquid hydrocarbon fuels because oxygen-aided reactions can break the aromatics in the fuel and steam can suppress carbon deposition during the reforming reaction. ATR can also be implemented as a self-sustaining reactor due to the exothermicity of the reaction. The kW e self-sustained kerosene fuel processor, including the desulfurizer, operates for about 250 h in this study. This fuel processor does not require a heat exchanger between the ATR reactor and the desulfurizer or electric equipment for heat supply and fuel or water vaporization because a suitable temperature of the ATR reformate is reached for H 2S adsorption on the ZnO catalyst beds in desulfurizer. Although the CH 4 concentration in the reformate gas of the fuel processor is higher due to the lower temperature of ATR tail gas, SOFCs can directly use CH 4 as a fuel with the addition of sufficient steam feeds (H 2O/CH 4 ≥ 1.5), in contrast to low-temperature fuel cells. The reforming efficiency of the fuel processor is about 60%, and the desulfurizer removed H 2S to a sufficient level to allow for the operation of SOFCs.

  5. ARF and ATM/ATR cooperate in p53-mediated apoptosis upon oncogenic stress

    SciTech Connect

    Pauklin, Siim . E-mail: spauklin@ut.ee; Kristjuhan, Arnold; Maimets, Toivo; Jaks, Viljar

    2005-08-26

    Induction of apoptosis is pivotal for eliminating cells with damaged DNA or deregulated proliferation. We show that tumor suppressor ARF and ATM/ATR kinase pathways cooperate in the induction of apoptosis in response to elevated expression of c-myc, {beta}-catenin or human papilloma virus E7 oncogenes. Overexpression of oncogenes leads to the formation of phosphorylated H2AX foci, induction of Rad51 protein levels and ATM/ATR-dependent phosphorylation of p53. Inhibition of ATM/ATR kinases abolishes both induction of Rad51 and phosphorylation of p53, and remarkably reduces the level of apoptosis induced by co-expression of oncogenes and ARF. However, the induction of apoptosis is downregulated in p53-/- cells and does not depend on activities of ATM/ATR kinases, indicating that efficient induction of apoptosis by oncogene activation depends on coordinated action of ARF and ATM/ATR pathways in the regulation of p53.

  6. Fabrication Control Plan for ORNL RH-LOCA ATF Test Specimens to be Irradiated in the ATR

    SciTech Connect

    Field, Kevin G.; Howard, Richard; Teague, Michael

    2014-06-01

    The purpose of this fabrication plan is (1) to summarize the design of a set of rodlets that will be fabricated and then irradiated in the Advanced Test Reactor (ATR) and (2) provide requirements for fabrication and acceptance criteria for inspections of the Light Water Reactor (LWR) – Accident Tolerant Fuels (ATF) rodlet components. The functional and operational (F&OR) requirements for the ATF program are identified in the ATF Test Plan. The scope of this document only covers fabrication and inspections of rodlet components detailed in drawings 604496 and 604497. It does not cover the assembly of these items to form a completed test irradiation assembly or the inspection of the final assembly, which will be included in a separate INL final test assembly specification/inspection document. The controls support the requirements that the test irradiations must be performed safely and that subsequent examinations must provide valid results.

  7. Catalytic autothermal reforming increases fuel cell flexibility

    NASA Technical Reports Server (NTRS)

    Flytzani-Stephanopoulos, M.; Voecks, G. E.

    1981-01-01

    Experimental results are presented for the autothermal reforming (ATR) of n-hexane, n-tetradecane, benzene and benzene solutions of naphthalene. The tests were run at atmospheric pressure and at moderately high reactant preheat temperatures in the 800-900 K range. Carbon formation lines were determined for paraffinic and aromatic liquids. Profiles were determined for axial bed temperature and composition. Space velocity efforts were assessed, and the locations and types of carbon were recorded. Significant reactive differences between hydrocarbons were identified. Carbon formation characteristics were hydrocarbon specific. The differing behavior of paraffinic and aromatic fuels with respect to their carbon formation may be important in explaining the narrow range of carbon-free operating conditions found in the ATR of number two fuel oil.

  8. Modern approaches in deep learning for SAR ATR

    NASA Astrophysics Data System (ADS)

    Wilmanski, Michael; Kreucher, Chris; Lauer, Jim

    2016-05-01

    Recent breakthroughs in computational capabilities and optimization algorithms have enabled a new class of signal processing approaches based on deep neural networks (DNNs). These algorithms have been extremely successful in the classification of natural images, audio, and text data. In particular, a special type of DNNs, called convolutional neural networks (CNNs) have recently shown superior performance for object recognition in image processing applications. This paper discusses modern training approaches adopted from the image processing literature and shows how those approaches enable significantly improved performance for synthetic aperture radar (SAR) automatic target recognition (ATR). In particular, we show how a set of novel enhancements to the learning algorithm, based on new stochastic gradient descent approaches, generate significant classification improvement over previously published results on a standard dataset called MSTAR.

  9. Dedicated SAR simulation tools for ATR and scene analysis

    NASA Astrophysics Data System (ADS)

    Hammer, Horst; Schulz, Karsten

    2011-11-01

    At Fraunhofer IOSB the SAR simulator suite CohRaSS (Coherent Raytracing SAR Simulator) dedicated to different, sometimes contradictory purposes is being developed. These include the simulation of very large scenes at high resolution for scene analysis purposes, the simulation of large quantities of training chips for classification and the very fast but less realistic simulation of scenes for use in the training of image analysts. These tasks have very different requirements for the simulation that cannot be met by one single program. Thus different, custom-tailored approaches for each of these tasks are being developed. This paper deals with the main aspects concerning the simulation of training chips for ATR and the simulation of large scenes at very high resolution. Special focus is set on the different approaches used for these tasks from a computational point of view. For both simulators, sample simulated images are shown.

  10. Deep convolutional neural networks for ATR from SAR imagery

    NASA Astrophysics Data System (ADS)

    Morgan, David A. E.

    2015-05-01

    Deep architectures for classification and representation learning have recently attracted significant attention within academia and industry, with many impressive results across a diverse collection of problem sets. In this work we consider the specific application of Automatic Target Recognition (ATR) using Synthetic Aperture Radar (SAR) data from the MSTAR public release data set. The classification performance achieved using a Deep Convolutional Neural Network (CNN) on this data set was found to be competitive with existing methods considered to be state-of-the-art. Unlike most existing algorithms, this approach can learn discriminative feature sets directly from training data instead of requiring pre-specification or pre-selection by a human designer. We show how this property can be exploited to efficiently adapt an existing classifier to recognise a previously unseen target and discuss potential practical applications.

  11. Modeling performance and image collection utility for multiple look ATR

    NASA Astrophysics Data System (ADS)

    Snyder, William C.; Ettinger, Gil J.; Laprise, S.

    2004-09-01

    We present a performance model for estimating the likelihood function and posterior probability of classes in a multiple-look SAR ATR classifier. We extend performance estimation to performance prediction in order to assess the effects of additional looks at different targets in a scene. This likelihood improvement model depends on a variety of factors including the resulting look angle diversity and the resolution of the sensor. The performance model parameters are estimated from classification scores and multi-look performance with real data, but could also be developed from simulations in cases where no data exist. Finally, we propose a transformation from the predicted performance to a value for each look that is used to optimize asset tasking. The value transformation is based on the target importance and absolute posterior probability.

  12. Thermal Analysis of Irradiation Experiments in the ATR

    SciTech Connect

    Paul Murray

    2012-09-01

    Reactor material testing in the INL's Advanced Test Reactor (ATR) involves modeling and simulation of each experiment to accurately determine the irradiation temperature. This paper describes thermal analysis of capsule experiments using gas gap temperature control and provides data on recent material tests that validate the modeling results. Static capsule experiments and lead-out capsule experiments are discussed. The source of temperature variation in capsule experiments and ways to mitigate these variations are also explained. Two examples of instrumented lead-out capsule experiments, TMIST-1 and UCSB-2, are presented. A comparison of measured and calculated temperatures is used to validate the thermal models and to ascertain the accuracy of the calculated temperature.

  13. Wurfelspiel-based training data methods for ATR

    NASA Astrophysics Data System (ADS)

    Peterson, James K.

    2004-09-01

    A data object is constructed from a P by M Wurfelspiel matrix W by choosing an entry from each column to construct a sequence A0A1"AM-1. Each of the PM possibilities are designed to correspond to the same category according to some chosen measure. This matrix could encode many types of data. (1) Musical fragments, all of which evoke sadness; each column entry is a 4 beat sequence with a chosen A0A1A2 thus 16 beats long (W is P by 3). (2) Paintings, all of which evoke happiness; each column entry is a layer and a given A0A1A2 is a painting constructed using these layers (W is P by 3). (3) abstract feature vectors corresponding to action potentials evoked from a biological cell's exposure to a toxin. The action potential is divided into four relevant regions and each column entry represents the feature vector of a region. A given A0A1A2 is then an abstraction of the excitable cell's output (W is P by 4). (4) abstract feature vectors corresponding to an object such as a face or vehicle. The object is divided into four categories each assigned an abstract feature vector with the resulting concatenation an abstract representation of the object (W is P by 4). All of the examples above correspond to one particular measure (sad music, happy paintings, an introduced toxin, an object to recognize)and hence, when a Wurfelspiel matrix is constructed, relevant training information for recognition is encoded that can be used in many algorithms. The focus of this paper is on the application of these ideas to automatic target recognition (ATR). In addition, we discuss a larger biologically based model of temporal cortex polymodal sensor fusion which can use the feature vectors extracted from the ATR Wurfelspiel data.

  14. IRRADIATION TESTING OF THE RERTR FUEL MINIPLATES WITH BURNABLE ABSORBERS IN THE ADVANCED TEST REACTOR

    SciTech Connect

    I. Glagolenko; D. Wachs; N. Woolstenhulme; G. Chang; B. Rabin; C. Clark; T. Wiencek

    2010-10-01

    Based on the results of the reactor physics assessment, conversion of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) can be potentially accomplished in two ways, by either using U-10Mo monolithic or U-7Mo dispersion type plates in the ATR fuel element. Both designs, however, would require incorporation of the burnable absorber in several plates of the fuel element to compensate for the excess reactivity and to flatten the radial power profile. Several different types of burnable absorbers were considered initially, but only borated compounds, such as B4C, ZrB2 and Al-B alloys, were selected for testing primarily due to the length of the ATR fuel cycle and fuel manufacturing constraints. To assess and compare irradiation performance of the U-Mo fuels with different burnable absorbers we have designed and manufactured 28 RERTR miniplates (20 fueled and 8 non-fueled) containing fore-mentioned borated compounds. These miniplates will be tested in the ATR as part of the RERTR-13 experiment, which is described in this paper. Detailed plate design, compositions and irradiations conditions are discussed.

  15. AGR-2 Data Qualification Report for ATR Cycles 147A, 148A, 148B, and 149A

    SciTech Connect

    Michael L. Abbott; Keith A. Daum

    2011-08-01

    This report presents the data qualification status of fuel irradiation data from the first four reactor cycles (147A, 148A, 148B, and 149A) of the on-going second Advanced Gas Reactor (AGR-2) experiment as recorded in the NGNP Data Management and Analysis System (NDMAS). This includes data received by NDMAS from the period June 22, 2010 through May 21, 2011. AGR-2 is the second in a series of eight planned irradiation experiments for the AGR Fuel Development and Qualification Program, which supports development of the very high temperature gas-cooled reactor (VHTR) under the Next Generation Nuclear Plant (NGNP) Project. Irradiation of the AGR-2 test train is being performed at the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) and is planned for 600 effective full power days (approximately 2.75 calendar years) (PLN-3798). The experiment is intended to demonstrate the performance of UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Data qualification status of the AGR-1 experiment was reported in INL/EXT-10-17943 (Abbott et al. 2010).

  16. Fuel Cycle Research and Development Accident Tolerant Fuels Series 1 (ATF-1) Irradiation Testing FY 2016 Status Report

    SciTech Connect

    Core, Gregory Matthew

    2016-09-01

    This report contains a summary of irradiation testing of Fuel Cycle Research and Development (FCRD) Accident Tolerant Fuels Series 1 (ATF 1) experiments performed at Idaho National Laboratory (INL) in FY 2016. ATF 1 irradiation testing work performed in FY 2016 included design, analysis, and fabrication of ATF-1B drop in capsule ATF 1 series experiments and irradiation testing of ATF-1 capsules in the ATR.

  17. AKAP12 mediates PKA-induced phosphorylation of ATR to enhance nucleotide excision repair

    PubMed Central

    Jarrett, Stuart G.; Wolf Horrell, Erin M.; D'Orazio, John A.

    2016-01-01

    Loss-of-function in melanocortin 1 receptor (MC1R), a GS protein-coupled receptor that regulates signal transduction through cAMP and protein kinase A (PKA) in melanocytes, is a major inherited melanoma risk factor. Herein, we report a novel cAMP-mediated response for sensing and responding to UV-induced DNA damage regulated by A-kinase-anchoring protein 12 (AKAP12). AKAP12 is identified as a necessary participant in PKA-mediated phosphorylation of ataxia telangiectasia mutated and Rad3-related (ATR) at S435, a post-translational event required for cAMP-enhanced nucleotide excision repair (NER). Moreover, UV exposure promotes ATR-directed phosphorylation of AKAP12 at S732, which promotes nuclear translocation of AKAP12–ATR-pS435. This complex subsequently recruits XPA to UV DNA damage and enhances 5′ strand incision. Preventing AKAP12's interaction with PKA or with ATR abrogates ATR-pS435 accumulation, delays recruitment of XPA to UV-damaged DNA, impairs NER and increases UV-induced mutagenesis. Our results define a critical role for AKAP12 as an UV-inducible scaffold for PKA-mediated ATR phosphorylation, and identify a repair complex consisting of AKAP12–ATR-pS435-XPA at photodamage, which is essential for cAMP-enhanced NER. PMID:27683220

  18. ATR suppresses telomere fragility and recombination but is dispensable for elongation of short telomeres by telomerase

    PubMed Central

    McNees, Carolyn J.; Tejera, Agueda M.; Martínez, Paula; Murga, Matilde; Mulero, Francisca; Fernandez-Capetillo, Oscar

    2010-01-01

    Telomere shortening caused by incomplete DNA replication is balanced by telomerase-mediated telomere extension, with evidence indicating that the shortest telomeres are preferred substrates in primary cells. Critically short telomeres are detected by the cellular DNA damage response (DDR) system. In budding yeast, the important DDR kinase Tel1 (homologue of ATM [ataxia telangiectasia mutated]) is vital for telomerase recruitment to short telomeres, but mammalian ATM is dispensable for this function. We asked whether closely related ATR (ATM and Rad3 related) kinase, which is important for preventing replicative stress and chromosomal breakage at common fragile sites, might instead fulfill this role. The newly created ATR-deficient Seckel mouse strain was used to examine the function of ATR in telomerase recruitment and telomere function. Telomeres were recently found to resemble fragile sites, and we show in this study that ATR has an important role in the suppression of telomere fragility and recombination. We also find that wild-type ATR levels are important to protect short telomeres from chromosomal fusions but do not appear essential for telomerase recruitment to short telomeres in primary mouse embryonic fibroblasts from the ATR-deficient Seckel mouse model. These results reveal a previously unnoticed role for mammalian ATR in telomere protection and stability. PMID:20212315

  19. ATR inhibition broadly sensitizes ovarian cancer cells to chemotherapy independent of BRCA status

    PubMed Central

    Huntoon, Catherine J.; Flatten, Karen S.; Wahner Hendrickson, Andrea E.; Huehls, Amelia M.; Sutor, Shari L.; Kaufmann, Scott H.; Karnitz, Larry M.

    2013-01-01

    Replication stress and DNA damage activate the ATR-CHK1 checkpoint signaling pathway that licenses repair and cell survival processes. In this study, we examined the respective roles of the ATR and CHK1 kinases in ovarian cancer cells using genetic and pharmacological inhibitors of in combination with cisplatin, topotecan, gemcitabine and the poly(ADP-ribose)-polymerase (PARP) inhibitor veliparib (ABT-888), four agents with clinical activity in ovarian cancer. RNAi-mediated depletion or inhibition of ATR sensitized ovarian cancer cells to all four agents. In contrast, while cisplatin, topotecan and gemcitabine each activated CHK1, RNAi-mediated depletion or inhibition of this kinase in cells sensitized them only to gemcitabine. Unexpectedly, we found that neither the ATR kinase inhibitor VE-821 or the CHK1 inhibitor MK-8776 blocked ATR-mediated CHK1 phosphorylation or autophosphorylation, two commonly used readouts for inhibition of the ATR-CHK1 pathway. Instead, their ability to sensitize cells correlated with enhanced CDC25A levels. Additionally, we also found that VE-821 could further sensitize BRCA1-depleted cells to cisplatin, topotecan and veliparib beyond the potent sensitization already caused by their deficiency in homologous recombination. Taken together, our results established that ATR and CHK1 inhibitors differentially sensitize ovarian cancer cells to commonly used chemotherapy agents, and that CHK1 phosphorylation status may not offer a reliable marker for inhibition of the ATR-CHK1 pathway. A key implication of our work is the clinical rationale it provides to evaluate ATR inhibitors in combination with PARP inhibitors in BRCA1/2-deficient cells. PMID:23548269

  20. Opportunities for mixed oxide fuel testing in the advanced test reactor to support plutonium disposition

    SciTech Connect

    Terry, W.K.; Ryskamp, J.M.; Sterbentz, J.W.

    1995-08-01

    Numerous technical issues must be resolved before LWR operating licenses can be amended to allow the use of MOX fuel. These issues include the following: (1) MOX fuel fabrication process verification; (2) Whether and how to use burnable poisons to depress MOX fuel initial reactivity, which is higher than that of urania; (3) The effects of WGPu isotopic composition; (4) The feasibility of loading MOX fuel with plutonia content up to 7% by weight; (5) The effects of americium and gallium in WGPu; (6) Fission gas release from MOX fuel pellets made from WGPu; (7) Fuel/cladding gap closure; (8) The effects of power cycling and off-normal events on fuel integrity; (9) Development of radial distributions of burnup and fission products; (10) Power spiking near the interfaces of MOX and urania fuel assemblies; and (11) Fuel performance code validation. The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory possesses many advantages for performing tests to resolve most of the issues identified above. We have performed calculations to show that the use of hafnium shrouds can produce spectrum adjustments that will bring the flux spectrum in ATR test loops into a good approximation to the spectrum anticipated in a commercial LWR containing MOX fuel while allowing operation of the test fuel assemblies near their optimum values of linear heat generation rate. The ATR would be a nearly ideal test bed for developing data needed to support applications to license LWRs for operation with MOX fuel made from weapons-grade plutonium. The requirements for planning and implementing a test program in the ATR have been identified. The facilities at Argonne National Laboratory-West can meet all potential needs for pre- and post-irradiation examination that might arise in a MOX fuel qualification program.

  1. Attenuated Total Reflection (ATR) Sampling in Infrared Spectroscopy of Heterogeneous Materials Requires Reproducible Pressure Control.

    PubMed

    Lu, Zhenyu; Cassidy, Brianna M; DeJong, Stephanie A; Belliveau, Raymond G; Myrick, Michael L; Morgan, Stephen L

    2017-01-01

    Attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy, in which the sample is pressed against an internal reflection element, is a popular technique for rapid IR spectral collection. However, depending on the accessory design, the pressure applied to the sample is not always well controlled. While collecting data from fabrics with heterogeneous coatings, we have observed systematic pressure-dependent changes in spectra that can be eliminated by more reproducible pressure control. We also described a pressure sensor adapted to work with an ATR tower to enable more precise control of pressure during ATR sampling.

  2. Measuring Photochemical Kinetics in Submonolayer Films by Transient ATR Spectroscopy on a Multimode Planar Waveguide

    SciTech Connect

    Simon, Anne M.; Marucci, Nicole E.; Saavedra, S. Scott

    2011-07-15

    Understanding the kinetics of reactions in molecular thin films can aid in the molecular engineering of organic photovoltaics and biosensors. Using two analytical methods, transient absorbance spectroscopy (TAS) and attenuated total reflectance (ATR), in a relatively simple arrangement when compared with previous TAS/ATR instruments to interrogate molecular structure and photochemistry at interfaces. The multimode planar waveguide geometry provides a significant path length enhancement relative to a conventional transmission geometry, making it feasible to perform measurements on low-surface-coverage films. This work demonstrates that TAS/ATR can be used to probe structure and photochemical kinetics in molecular films at extremely low surface coverages.

  3. Status of ATR-A1 irradiation experiment on vanadium alloys and low-activation steels

    SciTech Connect

    Tsai, H.; Strain, R.V.; Gomes, I.; Chung, H.; Smith, D.L.

    1997-04-01

    The ATR-A1 irradiation experiment in the Advanced Test Reactor (ATR) was a collaborative U.S./Japan effort to study at low temperatures the effects of neutron damage on vanadium alloys. The experiment also contained a limited quantity of low-activation ferritic steel specimens from Japan as part of the collaboration agreement. The irradiation was completed on May 5, 1996, as planned, after achieving an estimated neutron damage of 4.7 dpa in vanadium. The capsule has since been kept in the ATR water canal for the required radioactivity cool-down. Planning is underway for disassembly of the capsule and test specimen retrieval.

  4. Identification of a Novel System for Boron Transport: Atr1 Is a Main Boron Exporter in Yeast▿ †

    PubMed Central

    Kaya, Alaattin; Karakaya, Huseyin C.; Fomenko, Dmitri E.; Gladyshev, Vadim N.; Koc, Ahmet

    2009-01-01

    Boron is a micronutrient in plants and animals, but its specific roles in cellular processes are not known. To understand boron transport and functions, we screened a yeast genomic DNA library for genes that confer resistance to the element in Saccharomyces cerevisiae. Thirty boron-resistant transformants were isolated, and they all contained the ATR1 (YML116w) gene. Atr1 is a multidrug resistance transport protein belonging to the major facilitator superfamily. C-terminal green fluorescent protein-tagged Atr1 localized to the cell membrane and vacuole, and ATR1 gene expression was upregulated by boron and several stress conditions. We found that atr1Δ mutants were highly sensitive to boron treatment, whereas cells overexpressing ATR1 were boron resistant. In addition, atr1Δ cells accumulated boron, whereas ATR1-overexpressing cells had low intracellular levels of the element. Furthermore, atr1Δ cells showed stronger boron-dependent phenotypes than mutants deficient in genes previously reported to be implicated in boron metabolism. ATR1 is widely distributed in bacteria, archaea, and lower eukaryotes. Our data suggest that Atr1 functions as a boron efflux pump and is required for boron tolerance. PMID:19414602

  5. Fueling systems

    SciTech Connect

    Gorker, G.E.

    1987-01-01

    This report deals with concepts of the Tiber II tokamak reactor fueling systems. Contained in this report are the fuel injection requirement data, startup fueling requirements, intermediate range fueling requirements, power range fueling requirements and research and development considerations. (LSR)

  6. Multi-fuel reformers for fuel cells used in transportation. Multi-fuel reformers: Phase 1 -- Final report

    SciTech Connect

    Not Available

    1994-05-01

    DOE has established the goal, through the Fuel Cells in Transportation Program, of fostering the rapid development and commercialization of fuel cells as economic competitors for the internal combustion engine. Central to this goal is a safe feasible means of supplying hydrogen of the required purity to the vehicular fuel cell system. Two basic strategies are being considered: (1) on-board fuel processing whereby alternative fuels such as methanol, ethanol or natural gas stored on the vehicle undergo reformation and subsequent processing to produce hydrogen, and (2) on-board storage of pure hydrogen provided by stationary fuel processing plants. This report analyzes fuel processor technologies, types of fuel and fuel cell options for on-board reformation. As the Phase 1 of a multi-phased program to develop a prototype multi-fuel reformer system for a fuel cell powered vehicle, the objective of this program was to evaluate the feasibility of a multi-fuel reformer concept and to select a reforming technology for further development in the Phase 2 program, with the ultimate goal of integration with a DOE-designated fuel cell and vehicle configuration. The basic reformer processes examined in this study included catalytic steam reforming (SR), non-catalytic partial oxidation (POX) and catalytic partial oxidation (also known as Autothermal Reforming, or ATR). Fuels under consideration in this study included methanol, ethanol, and natural gas. A systematic evaluation of reforming technologies, fuels, and transportation fuel cell applications was conducted for the purpose of selecting a suitable multi-fuel processor for further development and demonstration in a transportation application.

  7. In-core flux sensor evaluations at the ATR critical facility

    SciTech Connect

    Troy Unruh; Benjamin Chase; Joy Rempe; David Nigg; George Imel; Jason Harris; Todd Sherman; Jean-Francois Villard

    2014-09-01

    Flux detector evaluations were completed as part of a joint Idaho State University (ISU) / Idaho National Laboratory (INL) / French Atomic Energy commission (CEA) ATR National Scientific User Facility (ATR NSUF) project to compare the accuracy, response time, and long duration performance of several flux detectors. Special fixturing developed by INL allows real-time flux detectors to be inserted into various ATRC core positions and perform lobe power measurements, axial flux profile measurements, and detector cross-calibrations. Detectors initially evaluated in this program include the French Atomic Energy Commission (CEA)-developed miniature fission chambers; specialized self-powered neutron detectors (SPNDs) developed by the Argentinean National Energy Commission (CNEA); specially developed commercial SPNDs from Argonne National Laboratory. As shown in this article, data obtained from this program provides important insights related to flux detector accuracy and resolution for subsequent ATR and CEA experiments and flux data required for bench-marking models in the ATR V&V Upgrade Initiative.

  8. ATR inhibitors as a synthetic lethal therapy for tumours deficient in ARID1A

    PubMed Central

    Williamson, Chris T.; Miller, Rowan; Pemberton, Helen N.; Jones, Samuel E.; Campbell, James; Konde, Asha; Badham, Nicholas; Rafiq, Rumana; Brough, Rachel; Gulati, Aditi; Ryan, Colm J.; Francis, Jeff; Vermulen, Peter B.; Reynolds, Andrew R.; Reaper, Philip M.; Pollard, John R.; Ashworth, Alan; Lord, Christopher J.

    2016-01-01

    Identifying genetic biomarkers of synthetic lethal drug sensitivity effects provides one approach to the development of targeted cancer therapies. Mutations in ARID1A represent one of the most common molecular alterations in human cancer, but therapeutic approaches that target these defects are not yet clinically available. We demonstrate that defects in ARID1A sensitize tumour cells to clinical inhibitors of the DNA damage checkpoint kinase, ATR, both in vitro and in vivo. Mechanistically, ARID1A deficiency results in topoisomerase 2A and cell cycle defects, which cause an increased reliance on ATR checkpoint activity. In ARID1A mutant tumour cells, inhibition of ATR triggers premature mitotic entry, genomic instability and apoptosis. The data presented here provide the pre-clinical and mechanistic rationale for assessing ARID1A defects as a biomarker of single-agent ATR inhibitor response and represents a novel synthetic lethal approach to targeting tumour cells. PMID:27958275

  9. Key mediators of somatic ATR signaling localize to unpaired chromosomes in spermatocytes

    PubMed Central

    Fedoriw, Andrew M.; Menon, Debashish; Kim, Yuna; Mu, Weipeng; Magnuson, Terry

    2015-01-01

    Meiotic silencing of unpaired chromatin (MSUC) occurs during the first meiotic prophase, as chromosomes that fail to pair are sequestered into a transcriptionally repressive nuclear domain. This phenomenon is exemplified by the heterologous sex chromosomes of male mammals, where the ATR DNA damage response kinase is crucial for this silencing event. However, the mechanisms underlying the initiation of MSUC remain unknown. Here, we show that essential components of ATR signaling in murine somatic cells are spatially confined to unpaired chromosomes in spermatocytes, including the ATR-dependent phosphorylation of the single-stranded DNA (ssDNA)-binding complex replication protein A (RPA) and the checkpoint kinase CHK1. These observations support a model in which ssDNA plays a central role in the recruitment of ATR during MSUC, and provide a link to meiotic progression through activation of CHK1. PMID:26209650

  10. Roles of ATR1 paralogs YMR279c and YOR378w in boron stress tolerance.

    PubMed

    Bozdag, Gonensin Ozan; Uluisik, Irem; Gulculer, Gulce Sila; Karakaya, Huseyin C; Koc, Ahmet

    2011-06-17

    Boron is a necessary nutrient for plants and animals, however excess of it causes toxicity. Previously, Atr1 and Arabidopsis Bor1 homolog were identified as the boron efflux pump in yeast, which lower the cytosolic boron concentration and help cells to survive in the presence of toxic amount of boron. In this study, we analyzed ATR1 paralogs, YMR279c and YOR378w, to understand whether they participate in boron stress tolerance in yeast. Even though these genes share homology with ATR1, neither their deletion rendered cells boron sensitive nor their expression was significantly upregulated by boron treatment. However, expression of YMR279, but not YOR378w, from the constitutive GAPDH promoter on a high copy plasmid provided remarkable boron resistance by decreasing intracellular boron levels. Thus our results suggest the presence of a third boron exporter, YMR279c, which functions similar to ATR1 and provides boron resistance in yeast.

  11. Preliminary Advanced Test Reactor LEU Fuel Conversion Feasibility Study

    SciTech Connect

    G. S. Chang; R. G. Ambrosek

    2005-11-01

    The Advanced Test Reactor (ATR) is a high power density, high neutron flux research reactor operating in the United States. The ATR has large irradiation test volumes located in high flux areas. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth with a maximum unperturbed thermal neutron flux rating of 1.0 x 1015 n/cm2–s. As a result, the ATR is a representative candidate for assessing the necessary modifications and evaluating the subsequent operating effects associated with low-enriched uranium (LEU) fuel conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed for the fuel cycle burnup comparison analysis. Using the current HEU 235U enrichment of 93.0 % as a baseline, an analysis can be performed to determine the LEU uranium density and 235U enrichment required in the fuel meat to yield an equivalent Keff between the HEU core and a LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the 235U loading in the LEU core, such that the differences in Keff between the HEU and LEU core can be minimized for operation at 150 EFPD with a total core power of 115 MW. The Monte-Carlo with ORIGEN-2 (MCWO) method was used to calculate Keff versus EFPDs. The MCWO-calculated results for the LEU case demonstrated adequate excess reactivity such that the LEU core conversion designer should be able to optimize the 235U content of each fuel plate, so that the Keff and relative radial fission heat flux profile are similar to the reference ATR HEU case. However, to demonstrate that the LEU core fuel cycle performance can meet the Upgraded Final Safety Analysis Report (UFSAR) safety requirements, a further study will be required in order to investigate the detailed radial, axial, and azimuthal heat flux profile variations versus EFPDs.

  12. Experimental active control of sound in the ATR 42

    NASA Astrophysics Data System (ADS)

    Paonessa, A.; Sollo, A.; Paxton, M.; Purver, M.; Ross, C. F.

    Passenger comfort is becoming day by day an important issue for the market of the regional turboprop aircraft and also for the future high speed propeller driven aircraft. In these aircraft the main contribution to the passenger annoyance is due to the propeller noise blade passing frequency (BPF) and its harmonics. In the recent past a detailed theoretical and experimental work has been done by Alenia Aeronautica in order to reduce the noise level in the ATR aircraft passenger cabin by means of conventional passive treatments: synchrophasing of propellers, dynamic vibration absorbers, structural reinforcements, damping materials. The application of these treatments has been introduced on production aircraft with a remarkable improvement of noise comfort but with a significant weight increase. For these reasons, a major technology step is required for reaching passenger comfort comparable to that of jet aircraft with the minimum weight increase. The most suitable approach to this problem has been envisaged in the active noise control which consists in generating an anti-sound field in the passenger cabin to reduce the noise at propeller BPF and its harmonics. The attenuation is reached by means of a control system which acquires information about the cabin noise distribution and the propeller speed during flight and simultaneously generates the signals to drive the speakers.

  13. Adaptive SAR ATR problem set (AdaptSAPS)

    NASA Astrophysics Data System (ADS)

    Wise, Angela R.; Fitzgerald, Donna; Ross, Timothy D.

    2004-09-01

    A strong and growing interest in systems that adapt to changing circumstances was evident in panel discussions at the "Algorithms for SAR Imagery" Conference of the AeroSense Symposium in April 2003, with DARPA, Air Force, industry and academia participation. As a result, Conference Co-Chair Mr. Ed Zelnio suggested producing a dynamic model to create problem sets suitable for adaptive system research and development. Such a problem set provides a framework for the overall problem, including organization of operating conditions, performance measures and specific test cases. It is hoped that this AdaptSAPS framework will help provide the community with a more concrete base for discussing adaptation in SAR imagery exploitation. AdaptSAPS Version 1.0 was produced by the AFRL COMPASE and SDMS organizations and posted on 5 August 2003. AdaptSAPS consists of over a dozen MatLab programs that allow the user to create "missions" with SAR data of varying complexities and then present that test data one image at a time, first as unexploited imagery and then later with the exploitation results that an ATR could use for adaptation in an operational environment. AdaptSAPS keeps track of performance results and reports performance measures. This paper describes AdaptSAPS - its application process and possible improvements as a problem set.

  14. Feature separability analysis for SAR ATR using data description method

    NASA Astrophysics Data System (ADS)

    Guo, Weiwei; Du, Xiaoyong; Hu, WeiDong; Yu, Wenxian

    2007-11-01

    Feature extraction and selection play an important role in radar target recognition. This paper focuses on evaluating feature separability for SAR ATR and selecting the best subset of features. In details, fifteen features extracted from T72, BTR70 and BMP2 in MSTAR standard public dataset are examined, which are divided into seven categories: standard deviation, fractal dimension, weighted-rank fill ratio, size-related features, contrast-based features, count feature, projection feature, and moment features. Since the number of samples is small, a new separability criterion based on the overlap degree of each two class regions is proposed to assess the separability of these features. Here the class region is described by support vector data description (SVDD) method for good generalization. Based on the proposed criterion, a forward feature selection method is adopted to choose the best subset of features. Because of the strong variability of the feature against aspect, the features are analyzed under different aspect sectors within 360°angle range stepped by 15°, 30 °, and 60°, respectively. Experiments using MSTAR dataset validate the criterion, and the best subset of features is determined.

  15. MINACE filter classification algorithms for ATR using MSTAR data

    NASA Astrophysics Data System (ADS)

    Patnaik, Rohit; Casasent, David

    2005-05-01

    A synthetic aperture radar (SAR) automatic target recognition (ATR) system based on the minimum noise and correlation energy (MINACE) distortion-invariant filter (DIF) is presented. A set of MINACE filters covering different aspect ranges is synthesized for each object using a training set of images of that object and a validation set of confuser and clutter images. No prior DIF work addressed confuser rejection. We also address use of fewer DIFs per object than prior work did. The selection of the MINACE filter parameter c for each filter is automated using training and validation sets. The system is evaluated using images from the Moving and Stationary Target Acquisition and Recognition (MSTAR) public database. The classification scores (PC) and the number of false alarm scores for confusers and clutter (PFA and PCFA respectively) are presented for the benchmark three-class MSTAR database with object variants and two confusers. The pose of the input test image is not assumed to be known, thus the problem addressed is more realistic than in prior work, since pose estimation of SAR objects has a large margin of error. Results for both confuser and clutter rejection are presented.

  16. EO/IR ATR performance modeling to support fusion experimentation

    NASA Astrophysics Data System (ADS)

    Kahler, Barton; Blasch, Erik; Pikas, David J.; Ross, Tim

    2007-04-01

    The identification of a target from an electro-optical or thermal imaging sensor requires accurate sensor registration, quality sensor data, and an exploitation algorithm. Combining the sensor data and exploitation, we are concerned with developing an electro-optical or infrared (EO/IR) performance model. To combat the registration issue, we need a detailed list of operating conditions (i.e. collection position) so that the sensor exploitation results can be evaluated with sensitivities to these operating conditions or collection parameters. The focus of this paper will build on the NVSED AQUIRE model2. We are also concerned with developing an EO/IR model that affords comparable operating condition parameters to a synthetic aperture radar (SAR) performance model. The choice of EO/IR modeling additions are focused on areas were Fusion Gain might be realized through an experiment tradeoff between multiple EO/IR looks for ATR exploitation fusion. The two additions to known EO/IR models discussed in the paper are (1) adjacency and (2) obscuration. The methods to account for these new operating conditions and the corresponding results on the modeled performance are presented in this paper.

  17. Confuser rejection performance of EMACH filters for MSTAR ATR

    NASA Astrophysics Data System (ADS)

    Casasent, David; Nehemiah, Avinash

    2006-04-01

    Synthetic aperture radar (SAR) automatic target recognition (ATR) based on the extended maximum average correlation height (EMACH) distortion invariant filter (DIF) is presented. Prior work on the EMACH filter addresses 3-class and 10 class classification with clutter rejection. However, the ability of the EMACH filter to reject confusers is not well known. This paper addresses this. We follow a benchmark procedure which involves classification of three object classes over 360° aspect angle differences and with depression angle and variant differences and rejection of two unseen confusers from the Moving and Stationary Target Acquisition and Recognition (MSTAR) public database. We present a scheme to select which training set images to include while making the filters, since it is not necessary to use all training set images to make the filters. Results for classification with both confuser and clutter rejection are presented. We also compare our work with prior EMACH MSTAR work. We find EMACH filters to have poor confuser and clutter rejection. We also correct prior EMACH clutter rejection performance results.

  18. UAV based distributed ATR under realistic simulated environmental effects

    NASA Astrophysics Data System (ADS)

    Chen, Xiaohan; Gong, Shanshan; Schmid, Natalia A.; Valenti, Matthew C.

    2007-04-01

    Over the past several years, the military has grown increasingly reliant upon the use of unattended aerial vehicles (UAVs) for surveillance missions. There is an increasing trend towards fielding swarms of UAVs operating as large-scale sensor networks in the air. Such systems tend to be used primarily for the purpose of acquiring sensory data with the goal of automatic detection, identification, and tracking objects of interest. These trends have been paralleled by advances in both distributed detection, image/signal processing and data fusion techniques. Furthermore, swarmed UAV systems must operate under severe constraints on environmental conditions and sensor limitations. In this work, we investigate the effects of environmental conditions on target detection and recognition performance in a UAV network. We assume that each UAV is equipped with an optical camera, and use a realistic computer simulation to generate synthetic images. The detection algorithm relies on Haar-based features while the automatic target recognition (ATR) algorithm relies on Bessel K features. The performance of both algorithms is evaluated using simulated images that closely mimic data acquired in a UAV network under realistic environmental conditions. We design several fusion techniques and analyze both the case of a single observation and the case of multiple observations of the same target.

  19. Methods to probe protein transitions with ATR infrared spectroscopy.

    PubMed

    Rich, Peter R; Iwaki, Masayo

    2007-06-01

    We describe techniques that can be used in conjunction with modern attenuated total reflection (ATR) infrared micro-prisms to allow proteins to be manipulated cyclically between different states whilst simultaneously monitoring both mid-IR and UV/visible/near IR changes. These methods provide increased flexibility of the types of changes that can be induced in proteins in comparison to transmission methods. Quantitative measurements can be made of vibrational changes associated with conversion between stable catalytic reaction intermediates, ligand binding and oxidation-reduction. Both hydrophobic and soluble proteins can be analysed and the ability to induce transitions repetitively allows IR difference spectra to be acquired at a signal/noise sufficient to resolve changes due to specific cofactors or amino acids. Such spectra can often be interpreted at the atomic level by standard IR methods of comparisons with model compounds, by isotope and mutation effects and, increasingly, by ab initio simulations. Combination of such analyses with atomic 3D structural models derived from X-ray and NMR studies can lead to a deeper understanding of molecular mechanisms of enzymatic reactions.

  20. Neutron dosimetry and damage calculations for the ATR-A1 irradiation

    SciTech Connect

    Greenwood, L.R.; Ratner, R.T.

    1998-09-01

    Neutron fluence measurements and radiation damage calculations are reported for the collaborative US/Japan ATR-A1 irradiation in the Advanced Test Reactor (ATR) at Idaho National Engineering Laboratory (INEL). The maximum total neutron fluence at midplane was 9.4 {times} 10{sup 21} n/cm{sup 2} (5.5 {times} 10{sup 21} n/cm{sup 2} above 0.1 MeV), resulting in about 4.6 dpa in vanadium.

  1. Roles of ATR1 paralogs YMR279c and YOR378w in boron stress tolerance

    SciTech Connect

    Bozdag, Gonensin Ozan; Uluisik, Irem; Gulculer, Gulce Sila; Karakaya, Huseyin C.; Koc, Ahmet

    2011-06-17

    Highlights: {yields} ATR1 paralog YMR279c plays role in boron detoxification. {yields} YMR279c overexpression lowers cytoplasmic boron levels. {yields} ATR1 paralog YOR378w has no roles in boron stress response. -- Abstract: Boron is a necessary nutrient for plants and animals, however excess of it causes toxicity. Previously, Atr1 and Arabidopsis Bor1 homolog were identified as the boron efflux pump in yeast, which lower the cytosolic boron concentration and help cells to survive in the presence of toxic amount of boron. In this study, we analyzed ATR1 paralogs, YMR279c and YOR378w, to understand whether they participate in boron stress tolerance in yeast. Even though these genes share homology with ATR1, neither their deletion rendered cells boron sensitive nor their expression was significantly upregulated by boron treatment. However, expression of YMR279, but not YOR378w, from the constitutive GAPDH promoter on a high copy plasmid provided remarkable boron resistance by decreasing intracellular boron levels. Thus our results suggest the presence of a third boron exporter, YMR279c, which functions similar to ATR1 and provides boron resistance in yeast.

  2. Achilles Tendon Reflex (ATR) in response to short exposures of microgravity and hypergravity

    NASA Technical Reports Server (NTRS)

    Fujii, M.; Jaweed, M.

    1992-01-01

    Previous studies indicate that latency and amplitude of the Achilles tendon reflex (ATR) are reduced after exposure to microgravity for 28 days. The objective of this study was to quantitatively measure the latency of ATR during brief (20 sec) exposure to microgravity in KC-135 parabolic flights. Methods: The ATR was elicited in ten men during parabolic flight with the ankle held neutrally, planarflexed, and dorsiflexed. During flight, the ATR was elicited during the zero G and 1.8 G phases. Postflight testing was performed flying back to the airfield. Latencies to onset of the ATR were calculated and analyses of variance were performed to determine the effect of gravity and ankle position on latency. Result: The mean latencies for zero-G, 1.8-G and postflight with the ankle in the neutral position were 32.7 plus or minus 0.5 ms, and 33.1 plus or minus 0.7 ms respectively, which were not significantly different. There was a trend toward prolongation of latencies postflight. The mean latency for those who were motion sick was 32.1 plus or minus 0.1 ms compared to 34.0 plus or minus 0.3 ms for those who were not sick. Conclusions: These studies indicate that neither the level of gravity nor ankle position significantly affected the latency of the ATR.

  3. Experimental feature-based SAR ATR performance evaluation under different operational conditions

    NASA Astrophysics Data System (ADS)

    Chen, Yin; Blasch, Erik; Chen, Huimin; Qian, Tao; Chen, Genshe

    2008-04-01

    Automatic target recognition (ATR) system performance over various operating conditions is of great interest in military applications. The performance of ATR system depends on many factors, such as the characteristics of input data, feature extraction methods, and classification algorithms. Generally speaking, ATR performance evaluation can be performed either theoretically or empirically. The theoretical evaluation method requires reasonably accurate underlying models for characterizing target/clutter data, which in many cases is unavailable. The empirical (experimental) evaluation method, on the other hand, needs a fairly large data set in order to conduct meaningful experimental tests. In this paper, we present experimental performance evaluation of ATR algorithms using the Moving and Stationary Target Acquisition and Recognition (MSTAR) data set. We conduct a comprehensive analysis of the ATR performance under different operating conditions. In the experimental tests, different feature extraction techniques, Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA) and kernel PCA, are employed on target SAR imagery to reduce the feature dimension. A number of classification approaches, Nearest Neighbor, Naive Bayes, Support Vector Machine are tested and compared for their classification accuracy under different conditions such as various feature dimensions, target classes, feature selection methods and input data quality. Our experimental results provide a guideline for selecting features and classifiers in ATR system using synthetic aperture radar (SAR) imagery.

  4. Modeling a 5 kWe planar solid oxide fuel cell based system operating on JP-8 fuel and a comparison with tubular cell based system for auxiliary and mobile power applications

    NASA Astrophysics Data System (ADS)

    Tanim, Tanvir; Bayless, David J.; Trembly, Jason P.

    2014-01-01

    A steady state planar solid oxide fuel cell (P-SOFC) based system operating on desulfurized JP-8 fuel was modeled using Aspen Plus simulation software for auxiliary and mobile power applications. An onboard autothermal reformer (ATR) employed to reform the desulfurized JP-8 fuel was coupled with the P-SOFC stack to provide for H2 and CO as fuel, minimizing the cost and complexity associated with hydrogen storage. Characterization of the ATR reformer was conducted by varying the steam to carbon ratio (H2O/C) from 0.1 to 1.0 at different ATR operating temperatures (700-800 °C) while maintaining the P-SOFC stack temperature at 850 °C. A fraction of the anode recycle was used as the steam and heat source for autothermal reforming of the JP-8 fuel, intending to make the system lighter and compact for mobile applications. System modeling revealed a maximum net AC efficiency of 37.1% at 700 °C and 29.2% at 800 °C ATR operating temperatures, respectively. Parametric analyses with respect to fuel utilization factor (Uf) and current density (j) were conducted to determine optimum operating conditions. Finally, the P-SOFC based system was compared with a previously published [1] tubular solid oxide fuel cell based (T-SOFC) system to identify the relative advantages over one another.

  5. Development of an LS-DYNA Model of an ATR42-300 Aircraft for Crash Simulation

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Fasanella, Edwin L.

    2004-01-01

    This paper describes the development of an LS-DYNA simulation of a vertical drop test of an ATR42-300 twin-turboprop high-wing commuter-class airplane. A 30-ft/s drop test of this aircraft was performed onto a concrete impact surface at the FAA Technical Center on July 30, 2003. The purpose of the test was to evaluate the structural response of a commuter-class aircraft when subjected to a severe, but survivable, impact. The aircraft was configured with crew and passenger seats, anthropomorphic test dummies, forward and aft luggage, instrumentation, and onboard data acquisition systems. The wings were filled with approximately 8,700 lb. of water to represent the fuel and the aircraft weighed a total of 33,200 lb. The model, which consisted of 57,643 nodes and 62,979 elements, was developed from direct measurements of the airframe geometry, over a period of approximately 8 months. The seats, dummies, luggage, fuel, and other ballast were represented using concentrated masses. Comparisons were made of the structural deformation and failure behavior of the airframe, as well as selected acceleration time history responses.

  6. A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

    SciTech Connect

    Navarro, Jorge

    2013-12-01

    The goal of this study presented is to determine the best available non-destructive technique necessary to collect validation data as well as to determine burn-up and cooling time of the fuel elements onsite at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads3 to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements non-destructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed was used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however in order to enhance the quality of the spectra collected using this scintillator a deconvolution method was developed. Following the development of the deconvolution method

  7. LIGHT WATER REACTOR ACCIDENT TOLERANT FUELS IRRADIATION TESTING

    SciTech Connect

    Carmack, William Jonathan; Barrett, Kristine Eloise; Chichester, Heather Jean MacLean

    2015-09-01

    The purpose of Accident Tolerant Fuels (ATF) experiments is to test novel fuel and cladding concepts designed to replace the current zirconium alloy uranium dioxide (UO2) fuel system. The objective of this Research and Development (R&D) is to develop novel ATF concepts that will be able to withstand loss of active cooling in the reactor core for a considerably longer time period than the current fuel system while maintaining or improving the fuel performance during normal operations, operational transients, design basis, and beyond design basis events. It was necessary to design, analyze, and fabricate drop-in capsules to meet the requirements for testing under prototypic LWR temperatures in Idaho National Laboratory's Advanced Test Reactor (ATR). Three industry led teams and one DOE team from Oak Ridge National Laboratory provided fuel rodlet samples for their new concepts for ATR insertion in 2015. As-built projected temperature calculations were performed on the ATF capsules using the BISON fuel performance code. BISON is an application of INL’s Multi-physics Object Oriented Simulation Environment (MOOSE), which is a massively parallel finite element based framework used to solve systems of fully coupled nonlinear partial differential equations. Both 2D and 3D models were set up to examine cladding and fuel performance.

  8. US Progress on Property Characterization to Support LEU U-10 Mo Monolithic Fuel Development

    SciTech Connect

    Cole, James Irvin; Rabin, Barry H; Smith, James Arthur; Scott, Clark Landon; Benefiel, Bradley Curtis; Larsen, Eric David; Lind, Robert Paul; Sell, David Alan

    2016-03-01

    The US High Performance Research Reactor program is pursuing development and qualification of a new high density monolithic LEU fuel to facilitate conversion of five higher power research reactors located in the US (ATR, HFIR, NBSR, MIT and MURR). In order to support fabrication development and fuel performance evaluations, new testing capabilities are being developed to evaluate the properties of fuel specimens. Residual stress and fuel-cladding bond strength are two characteristics related to fuel performance that are being investigated. In this overview, new measurement capabilities being developed to assess these characteristics in both fresh and irradiated fuel are described. Progress on fresh fuel testing is summarized and on-going hot-cell implementation efforts to support future PIE campaigns are detailed. It is anticipated that benchmarking of as-fabricated fuel characteristics will be critical to establishing technical bases for specifications that optimize fuel fabrication and ensure acceptable in-reactor fuel performance.

  9. Tim-Tipin dysfunction creates an indispensible reliance on the ATR-Chk1 pathway for continued DNA synthesis.

    PubMed

    Smith, Kevin D; Fu, Michael A; Brown, Eric J

    2009-10-05

    The Tim (Timeless)-Tipin complex has been proposed to maintain genome stability by facilitating ATR-mediated Chk1 activation. However, as a replisome component, Tim-Tipin has also been suggested to couple DNA unwinding to synthesis, an activity expected to suppress single-stranded DNA (ssDNA) accumulation and limit ATR-Chk1 pathway engagement. We now demonstrate that Tim-Tipin depletion is sufficient to increase ssDNA accumulation at replication forks and stimulate ATR activity during otherwise unperturbed DNA replication. Notably, suppression of the ATR-Chk1 pathway in Tim-Tipin-deficient cells completely abrogates nucleotide incorporation in S phase, indicating that the ATR-dependent response to Tim-Tipin depletion is indispensible for continued DNA synthesis. Replication failure in ATR/Tim-deficient cells is strongly associated with synergistic increases in H2AX phosphorylation and DNA double-strand breaks, suggesting that ATR pathway activation preserves fork stability in instances of Tim-Tipin dysfunction. Together, these experiments indicate that the Tim-Tipin complex stabilizes replication forks both by preventing the accumulation of ssDNA upstream of ATR-Chk1 function and by facilitating phosphorylation of Chk1 by ATR.

  10. Fossil fuels -- future fuels

    SciTech Connect

    1998-03-01

    Fossil fuels -- coal, oil, and natural gas -- built America`s historic economic strength. Today, coal supplies more than 55% of the electricity, oil more than 97% of the transportation needs, and natural gas 24% of the primary energy used in the US. Even taking into account increased use of renewable fuels and vastly improved powerplant efficiencies, 90% of national energy needs will still be met by fossil fuels in 2020. If advanced technologies that boost efficiency and environmental performance can be successfully developed and deployed, the US can continue to depend upon its rich resources of fossil fuels.

  11. Mixed oxide fuels testing in the advanced test reactor to support plutonium disposition

    SciTech Connect

    Ryskamp, J.M.; Sterbentz, J.W.; Chang, G.S.

    1995-09-01

    An intense worldwide effort is now under way to find means of reducing the stockpile of weapons-grade plutonium. One of the most attractive solutions would be to use WGPu as fuel in existing light water reactors (LWRs) in the form of mixed oxide (MOX) fuel - i.e., plutonia (PUO{sub 2}) mixed with urania (UO{sub 2}). Before U.S. reactors could be used for this purpose, their operating licenses would have to be amended. Numerous technical issues must be resolved before LWR operating licenses can be amended to allow the use of MOX fuel. These issues include the following: (1) MOX fuel fabrication process verification, (2) Whether and how to use burnable poisons to depress MOX fuel initial reactivity, which is higher than that of urania, (3) The effects of WGPu isotopic composition, (4) The feasibility of loading MOX fuel with plutonia content up to 7% by weight, (5) The effects of americium and gallium in WGPu, (6) Fission gas release from MOX fuel pellets made from WGPu, (7) Fuel/cladding gap closure, (8) The effects of power cycling and off-normal events on fuel integrity, (9) Development of radial distributions of burnup and fission products, (10) Power spiking near the interfaces of MOX and urania fuel assemblies, and (11) Fuel performance code validation. We have performed calculations to show that the use of hafnium shrouds can produce spectrum adjustments that will bring the flux spectrum in ATR test loops into a good approximation to the spectrum anticipated in a commercial LWR containing MOX fuel while allowing operation of the test fuel assemblies near their optimum values of linear heat generation rate. The ATR would be a nearly ideal test bed for developing data needed to support applications to license LWRs for operation with MOX fuel made from weapons-grade plutonium. The requirements for planning and implementing a test program in the ATR have been identified.

  12. RERTR Fuel Developmemt and Qualification Plan

    SciTech Connect

    Dan Wachs

    2007-01-01

    In late 2003 it became evident that U-Mo aluminum fuels under development exhibited significant fuel performance problems under the irradiation conditions required for conversion of most high-powered research reactors. Solutions to the fuel performance issue have been proposed and show promise in early testing. Based on these results, a Reduced Enrichment Research and Test Reactor (RERTR) program strategy has been mapped to allow generic fuel qualification to occur prior to the end of FY10 and reactor conversion to occur prior to the end of FY14. This strategy utilizes a diversity of technologies, test conditions, and test types. Scoping studies using miniature fuel plates will be completed in the time frame of 2006-2008. Irradiation of larger specimens will occur in the Advanced Test Reactor (ATR) in the United States, the Belgian Reactor-2 (BR2) reactor in Belgium, and in the OSIRIS reactor in France in 2006-2009. These scoping irradiation tests provide a large amount of data on the performance of advanced fuel types under irradiation and allow the down selection of technology for larger scale testing during the final stages of fuel qualification. In conjunction with irradiation testing, fabrication processes must be developed and made available to commercial fabricators. The commercial fabrication infrastructure must also be upgraded to ensure a reliable low enriched uranium (LEU) fuel supply. Final qualification of fuels will occur in two phases. Phase I will obtain generic approval for use of dispersion fuels with density less than 8.5 g-U/cm3. In order to obtain this approval, a larger scale demonstration of fuel performance and fabrication technology will be necessary. Several Materials Test Reactor (MTR) plate-type fuel assemblies will be irradiated in both the High Flux Reactor (HFR) and the ATR (other options include the BR2 and Russian Research Reactor, Dmitrovgrad, Russia [MIR] reactors) in 2008-2009. Following postirradiation examination, a report

  13. DNA structure-specific priming of ATR activation by DNA-PKcs

    PubMed Central

    Vidal-Eychenié, Sophie; Décaillet, Chantal; Basbous, Jihane

    2013-01-01

    Three phosphatidylinositol-3-kinase–related protein kinases implement cellular responses to DNA damage. DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and ataxia-telangiectasia mutated respond primarily to DNA double-strand breaks (DSBs). Ataxia-telangiectasia and RAD3-related (ATR) signals the accumulation of replication protein A (RPA)–covered single-stranded DNA (ssDNA), which is caused by replication obstacles. Stalled replication intermediates can further degenerate and yield replication-associated DSBs. In this paper, we show that the juxtaposition of a double-stranded DNA end and a short ssDNA gap triggered robust activation of endogenous ATR and Chk1 in human cell-free extracts. This DNA damage signal depended on DNA-PKcs and ATR, which congregated onto gapped linear duplex DNA. DNA-PKcs primed ATR/Chk1 activation through DNA structure-specific phosphorylation of RPA32 and TopBP1. The synergistic activation of DNA-PKcs and ATR suggests that the two kinases combine to mount a prompt and specific response to replication-born DSBs. PMID:23897887

  14. ATR suppresses endogenous DNA damage and allows completion of homologous recombination repair.

    PubMed

    Brown, Adam D; Sager, Brian W; Gorthi, Aparna; Tonapi, Sonal S; Brown, Eric J; Bishop, Alexander J R

    2014-01-01

    DNA replication fork stalling or collapse that arises from endogenous damage poses a serious threat to genome stability, but cells invoke an intricate signaling cascade referred to as the DNA damage response (DDR) to prevent such damage. The gene product ataxia telangiectasia and Rad3-related (ATR) responds primarily to replication stress by regulating cell cycle checkpoint control, yet it's role in DNA repair, particularly homologous recombination (HR), remains unclear. This is of particular interest since HR is one way in which replication restart can occur in the presence of a stalled or collapsed fork. Hypomorphic mutations in human ATR cause the rare autosomal-recessive disease Seckel syndrome, and complete loss of Atr in mice leads to embryonic lethality. We recently adapted the in vivo murine pink-eyed unstable (pun) assay for measuring HR frequency to be able to investigate the role of essential genes on HR using a conditional Cre/loxP system. Our system allows for the unique opportunity to test the effect of ATR loss on HR in somatic cells under physiological conditions. Using this system, we provide evidence that retinal pigment epithelium (RPE) cells lacking ATR have decreased density with abnormal morphology, a decreased frequency of HR and an increased level of chromosomal damage.

  15. Portable scalable architecture for model-based FLIR ATR and SAR/FLIR fusion

    NASA Astrophysics Data System (ADS)

    Stephan, Larisa; Childs, Martin B.; Pujara, Neeraj

    1999-08-01

    For an on-board automatic target recognition (ATR) system to be useful to the crew of a military platform, the ATR must reduce the mission risk or increase its lethality. This utility may be increased by shortening the operator's time to interrogate possible threat targets or by enabling weapon deployment at a greater range. Obstacles to deployment of ATRs have included an excess of false cues and difficulty in adapting developmental configurations to processing architectures that can operate in the required environmental conditions without serious performance degradation. We present a real-time FLIR ATR software architecture that is scaleable across multiple processors and readily portable to a number of hardware platforms. Fusion with cues from an on- or off-board synthetic aperture radar (SAR) provides a significant reduction in the amount of processing required to classify targets while simultaneously increasing the confidence in each target hypothesis. The FLIR ATR and fusion are implemented on commercial off-the-shelf (COTS) processors that are available in ruggedized versions, and the software is constructed to allow portability to other processor families without major disturbance to those parts of the code that embody the algorithm content.

  16. ATR-ATRIP kinase complex triggers activation of the Fanconi anemia DNA repair pathway.

    PubMed

    Shigechi, Tomoko; Tomida, Junya; Sato, Koichi; Kobayashi, Masahiko; Eykelenboom, John K; Pessina, Fabio; Zhang, Yanbin; Uchida, Emi; Ishiai, Masamichi; Lowndes, Noel F; Yamamoto, Kenichi; Kurumizaka, Hitoshi; Maehara, Yoshihiko; Takata, Minoru

    2012-03-01

    ATR kinase activates the S-phase checkpoint when replication forks stall at sites of DNA damage. This event also causes phosphorylation of the Fanconi anemia (FA) protein FANCI, triggering its monoubiquitination of the key DNA repair factor FANCD2 by the FA core E3 ligase complex, thereby promoting this central pathway of DNA repair which permits replication to be restarted. However, the interplay between ATR and the FA pathway has been unclear. In this study, we present evidence that their action is directly linked, gaining insights into this relationship in a DT40 mutant cell line that is conditionally deficient in the critical ATR-binding partner protein ATRIP. Using this system, we showed that ATRIP was crucial for DNA damage-induced FANCD2 monoubiquitination and FANCI phosphorylation. ATR kinase phosphorylated recombinant FANCI protein in vitro, which was facilitated by the presence of FANCD2. Mechanistic investigations revealed that the RPA region but not the TopBP1 region of ATRIP was required for FANCD2 monoubiquitination, whereas Chk1 phosphorylation relied upon both domains. Together, our findings identify ATR as the kinase responsible for activating the FA pathway of DNA repair.

  17. Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments

    SciTech Connect

    Tomberlin, Terry Alan

    2002-06-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Test Reactor (ATR), a DOE Category A reactor, was designed to provide an irradiation test environment for conducting a variety of experiments. The ATR Safety Analysis Report, determined by DOE to meet the requirements of 10 CFR 830, Subpart B, provides versatility in types of experiments that may be conducted. This paper addresses two general types of experiments in the ATR facility and how safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore this type of experiment is addressed with more detail in the safety basis. This allows individual safety analyses for these experiments to be more routine and repetitive. The second type of experiment is less defined and is permitted under more general controls. Therefore, individual safety analyses for the second type of experiment tend to be more unique from experiment to experiment. Experiments are also discussed relative to "major modifications" and DOE-STD-1027-92. Application of the USQ process to ATR experiments is also discussed.

  18. Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments

    SciTech Connect

    Tomberlin, T.A.

    2002-06-19

    The Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Test Reactor (ATR), a DOE Category A reactor, was designed to provide an irradiation test environment for conducting a variety of experiments. The ATR Safety Analysis Report, determined by DOE to meet the requirements of 10 CFR 830, Subpart B, provides versatility in types of experiments that may be conducted. This paper addresses two general types of experiments in the ATR facility and how safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore this type of experiment is addressed with more detail in the safety basis. This allows individual safety analyses for these experiments to be more routine and repetitive. The second type of experiment is less defined and is permitted under more general controls. Therefore, individual safety analyses for the second type of experiment tend to be more unique from experiment to experiment. Experiments are also discussed relative to ''major modifications'' and DOE-STD-1027-92. Application of the USQ process to ATR experiments is also discussed.

  19. Verification and Validation of Corrected Versions of RELAP5 for ATR Reactivity Analyses

    SciTech Connect

    Cliff B. Davis

    2008-11-01

    Two versions of the RELAP5 computer code, RELAP5/MOD2.5 and RELAP5/MOD3 Version 3.2.1.2, are used to support safety analyses of the Advanced Test Reactor (ATR). Both versions of RELAP5 contain a point reactor kinetics model that has been used to simulate power excursion transients at the ATR. Errors in the RELAP5 point kinetics model were reported to the RELAP5 code developers in 2007. These errors had the potential to affect reactivity analyses that are part of the ATR’s safety basis. Consequently, corrected versions of RELAP5 were developed for analysis of the ATR. Four reactivity transients were simulated to verify and validate the corrected codes for use in safety evaluations of the ATR. The objectives of this paper are to describe the verification and validation of the point kinetics model for ATR applications and to inform code users of the effects of the errors on representative reactivity analyses.

  20. Corrosion Evaluation of RERTR Uranium Molybdenum Fuel

    SciTech Connect

    A K Wertsching

    2012-09-01

    As part of the National Nuclear Security Agency (NNSA) mandate to replace the use of highly enriched uranium (HEU) fuel for low enriched uranium (LEU) fuel, research into the development of LEU fuel for research reactors has been active since the late 1970’s. Originally referred to as the Reduced Enrichment for Research and Test Reactor (RERTR) program the new effort named Global Threat Reduction Initiative (GTRI) is nearing the goal of replacing the standard aluminum clad dispersion highly enriched uranium aluminide fuel with a new LEU fuel. The five domestic high performance research reactors undergoing this conversion are High Flux Isotope reactor (HFIR), Advanced Test Reactor (ATR), National Institute of Standards and Technology (NIST) Reactor, Missouri University Research Reactor (MURR) and the Massachusetts Institute of Technology Reactor II (MITR-II). The design of these reactors requires a higher neutron flux than other international research reactors, which to this point has posed unique challenges in the design and development of the new mandated LEU fuel. The new design utilizes a monolithic fuel configuration in order to obtain sufficient 235U within the LEU stoichoimetry to maintain the fission reaction within the domestic test reactors. The change from uranium aluminide dispersion fuel type to uranium molybdenum (UMo) monolithic configuration requires examination of possible corrosion issues associated with the new fuel meat. A focused analysis of the UMo fuel under potential corrosion conditions, within the ATR and under aqueous storage indicates a slow and predictable corrosion rate. Additional corrosion testing is recommended for the highest burn-up fuels to confirm observed corrosion rate trends. This corrosion analysis will focus only on the UMo fuel and will address corrosion of ancillary components such as cladding only in terms of how it affects the fuel. The calculations and corrosion scenarios are weighted with a conservative bias to

  1. 10 CFR 830 Major Modification Determination for Replacement of ATR Primary Coolant Pumps and Motors

    SciTech Connect

    Noel Duckwitz

    2011-05-01

    The continued safe and reliable operation of the ATR is critical to the Department of Energy (DOE) Office of Nuclear Energy (NE) mission. While ATR is safely fulfilling current mission requirements, a variety of aging and obsolescence issues challenge ATR engineering and maintenance personnel’s capability to sustain ATR over the long term. First documented in a series of independent assessments, beginning with an OA Environmental Safety and Health Assessment conducted in 2003, the issues were validated in a detailed Material Condition Assessment (MCA) conducted as a part of the ATR Life Extension Program in 2007.Accordingly, near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE’s long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent subprojects. The first project will replace the existent diesel-electrical bus (E-3), switchgear, and the 50-year-old obsolescent marine diesels with commercial power that is backed with safety related emergency diesel generators, switchgear, and uninterruptible power supply (UPS). The second project, the subject of this major modification determination, will replace the four, obsolete, original primary coolant pumps (PCPs) and motors. Completion of this and the two other age-related projects (replacement of the ATR diesel bus [E-3] and switchgear and replacement of the existent emergency firewater injection system) will resolve major age-related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the project pre-conceptual design identified several issues that lead to the conclusion that the project is a major modification: 1. Evaluation Criteria #3 (Change of existing process). The proposed strategy for equipping the replacement PCPs with VFDs

  2. [Relationship between PMI and ATR-FTIR Spectral Changes in Swine Costal Cartilages and Ribs].

    PubMed

    Yao, Yao; Wang, Qi; Jing, Xiao-li; Li, Bing; Zhang, Yin-ming; Wang, Zhi-jun; Li, Cheng-zhi; Lin, Han-cheng; Zhang, Ji; Huang, Ping; Wang, Zhen-yuan

    2016-02-01

    To analyze postmortem chemical changes in Landrace costal cartilages and ribs using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and to provide a novel technique for estimation of postmortem interval (PMI). The swines were sacrificed by hemorrhage and their costal cartilages and ribs were kept in 20 degrees C. The chemical analysis of the costal cartilages and ribs were performed using ATR-FTIR every 72 h. The correlation between the certain spectral parameters and PMI was also analyzed. The time-dependent changes of costal cartilages were more significant than ribs. There were no obvious changes for the main absorbance bands position, and some absorbance band ratios showed time-dependent changes and significant correlations with the PMI. ATR-FTIR has the ability to analyze postmortem chemical changes of the swine costal cartilages and ribs, and it can be a new method to estimate PMI based on spectroscopy.

  3. An attenuated total reflectance mid infrared (ATR-MIR) spectroscopy study of gelatinization in barley.

    PubMed

    Cozzolino, D; Roumeliotis, S; Eglinton, J

    2014-08-08

    The aim of this study was to evaluate the use of attenuated total reflectance and mid infrared (ATR-MIR) spectroscopy and to understand the gelatinization and retro-gradation of flour barley samples and the relationship with malting quality. Samples were sourced from two commercial barley varieties exhibiting high hot water extract (HWE) namely Navigator (n=8), and Admiral (n=8). Samples were analysed using the Rapid Visco Analyser (RVA) and ATR-MIR analysis. These results showed that ATR-MIR spectroscopy is capable of characterising gel samples derived from barley flour samples having different malting characteristics. Infrared spectra can effectively represent a 'fingerprint' of the sample being analysed and can be used to simplify and reduce analytical times in the routine methods currently used. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Measured Thermal and Fast Neutron Fluence Rates for ATF-1 Holders During ATR Cycle 157D

    SciTech Connect

    Smith, Larry Don; Miller, David Torbet

    2016-03-01

    This report contains the thermal (2200 m/s) and fast (E>1MeV) neutron fluence rate data for the ATF-1 holders located in core for ATR Cycle 157D which were measured by the Radiation Measurements Laboratory (RML) as requested by the Power Reactor Programs (ATR Experiments) Radiation Measurements Work Order. This report contains measurements of the fluence rates corresponding to the particular elevations relative to the 80-ft. core elevation. The data in this report consist of (1) a table of the ATR power history and distribution, (2) a hard copy listing of all thermal and fast neutron fluence rates, and (3) plots of both the thermal and fast neutron fluence rates. The fluence rates reported are for the average power levels given in the table of power history and distribution.

  5. IN-CORE FLUX SENSOR EVALUATIONS AT THE ATR CRITICAL FACILITY.

    SciTech Connect

    Troy Unruh; Benjamin Chase; Joy Rempe; David Nigg; George Imel; Jason Harris; Todd Sherman; Jean-Francois VIllard

    2014-12-01

    As part of an Idaho State University (ISU)–led Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) collaborative project that includes Idaho National Laboratory (INL) and the French Alternative Energies and Atomic Energy Commission (CEA), flux detector evaluations were completed to compare their accuracy, response time, and longduration performance. Special fixturing, developed by INL, allows real-time flux detectors to be inserted into various Advanced Test Reactor Critical Facility (ATRC) core positions to perform lobe power measurements, axial flux profile measurements, and detector crosscalibrations. Detectors initially evaluated in this program included miniature fission chambers, specialized self-powered neutron detectors (SPNDs), and specially developed commercial SPNDs. Results from this program provide important insights related to flux detector accuracy and resolution for subsequent ATR and CEA experiments and yield new flux data required for benchmarking models in the ATR Life Extension Program (LEP) Modeling Update Project.

  6. Modeling the attenuated total reflectance infrared (ATR-FTIR) spectrum of apatite

    NASA Astrophysics Data System (ADS)

    Aufort, Julie; Ségalen, Loïc; Gervais, Christel; Brouder, Christian; Balan, Etienne

    2016-10-01

    Attenuated total reflectance (ATR) infrared spectra were measured on a synthetic and a natural fluorapatite sample. A modeling approach based on the computation of the Fresnel reflection coefficient between the ATR crystal and the powder sample was used to analyze the line shape of the spectra. The dielectric properties of the samples were related to those of pure fluorapatite using an effective medium approach, based on Maxwell-Garnett and Bruggeman models. The Bruggeman effective medium model leads to a very good agreement with the experimental data recorded on the synthetic fluorapatite sample. The poorer agreement observed on the natural sample suggests a more significant heterogeneity of the sample at a characteristic length scale larger than the mid-infrared characteristic wavelength, i.e., about 10 micrometers. The results demonstrate the prominent role of macroscopic electrostatic effects over fine details of the microscopic structure in determining the line shape of strong ATR bands.

  7. Status of ATR-A1 irradiation experiment on vanadium alloys and low-activation steels

    SciTech Connect

    Tsai, H.; Strain, R.V.; Gomes, I.; Smith, D.L.; Matsui, H.

    1996-10-01

    The ATR-A1 irradiation experiment was a collaborative U.S./Japan effort to study at low temperature the effects of neutron damage on vanadium alloys. The experiment also contained a limited quantity of low-activation ferritic steel specimens from Japan as part of the collaboration agreement. The irradiation started in the Advanced Test Reactor (ATR) on November 30, 1995, and ended as planned on May 5, 1996. Total exposure was 132.9 effective full power days (EFPDs) and estimated neutron damage in the vanadium was 4.7 dpa. The vehicle has been discharged from the ATR core and is scheduled to be disassembled in the next reporting period.

  8. Depletion of ATR selectively sensitizes ATM-deficient human mammary epithelial cells to ionizing radiation and DNA-damaging agents.

    PubMed

    Cui, Yuxia; Palii, Stela S; Innes, Cynthia L; Paules, Richard S

    2014-01-01

    DNA damage response (DDR) to double strand breaks is coordinated by 3 phosphatidylinositol 3-kinase-related kinase (PIKK) family members: the ataxia-telangiectasia mutated kinase (ATM), the ATM and Rad3-related (ATR) kinase and the catalytic subunit of the DNA-dependent protein kinase (DNA-PKcs). ATM and ATR are central players in activating cell cycle checkpoints and function as an active barrier against genome instability and tumorigenesis in replicating cells. Loss of ATM function is frequently reported in various types of tumors, thus placing more reliance on ATR for checkpoint arrest and cell survival following DNA damage. To investigate the role of ATR in the G2/M checkpoint regulation in response to ionizing radiation (IR), particularly when ATM is deficient, cell lines deficient of ATM, ATR, or both were generated using a doxycycline-inducible lentiviral system. Our data suggests that while depletion of ATR or ATM alone in wild-type human mammary epithelial cell cultures (HME-CCs) has little effect on radiosensitivity or IR-induced G2/M checkpoint arrest, depletion of ATR in ATM-deficient cells causes synthetic lethality following IR, which correlates with severe G2/M checkpoint attenuation. ATR depletion also inhibits IR-induced autophagy, regardless of the ATM status, and enhances IR-induced apoptosis particularly when ATM is deficient. Collectively, our results clearly demonstrate that ATR function is required for the IR-induced G2/M checkpoint activation and subsequent survival of cells with ATM deficiency. The synthetic lethal interaction between ATM and ATR in response to IR supports ATR as a therapeutic target for improved anti-cancer regimens, especially in tumors with a dysfunctional ATM pathway.

  9. APE2 is required for ATR-Chk1 checkpoint activation in response to oxidative stress

    PubMed Central

    Willis, Jeremy; Patel, Yogin; Lentz, Barry L.; Yan, Shan

    2013-01-01

    The base excision repair pathway is largely responsible for the repair of oxidative stress-induced DNA damage. However, it remains unclear how the DNA damage checkpoint is activated by oxidative stress at the molecular level. Here, we provide evidence showing that hydrogen peroxide (H2O2) triggers checkpoint kinase 1 (Chk1) phosphorylation in an ATR [ataxia-telangiectasia mutated (ATM) and Rad3-related]-dependent but ATM-independent manner in Xenopus egg extracts. A base excision repair protein, Apurinic/apyrimidinic (AP) endonuclease 2 (APE2, APN2, or APEX2), is required for the generation of replication protein A (RPA)-bound single-stranded DNA, the recruitment of a checkpoint protein complex [ATR, ATR-interacting protein (ATRIP), and Rad9] to damage sites, and H2O2-induced Chk1 phosphorylation. A conserved proliferating cell nuclear antigen interaction protein box of APE2 is important for the recruitment of APE2 to H2O2-damaged chromatin. APE2 3′-phosphodiesterase and 3′-5′ exonuclease activity is essential for single-stranded DNA generation in the 3′–5′ direction from single-stranded breaks, referred to as single-stranded break end resection. In addition, APE2 associates with Chk1, and a serine residue (S86) in the Chk1-binding motif of APE2 is essential for Chk1 phosphorylation, indicating a Claspin-like but distinct role for APE2 in ATR-Chk1 signaling. Our data indicate that APE2 plays a vital and previously unexpected role in ATR-Chk1 checkpoint signaling in response to oxidative stress. Thus, our findings shed light on a distinct mechanism of how an ATR-Chk1–dependent DNA damage checkpoint is mediated by APE2 in the oxidative stress response. PMID:23754435

  10. 10 CFR 830 Major Modification Determination for the ATR Diesel Bus (E-3) and Switchgear Replacement

    SciTech Connect

    Noel Duckwtiz

    2011-05-01

    Near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE’s long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent subprojects. The first project, subject of this determination, will replace the existent diesel-electrical bus (E-3) and associated switchgear. More specifically, INL proposes transitioning ATR to 100% commercial power with appropriate emergency backup to include: • Provide commercial power as the normal source of power to the ATR loads currently supplied by diesel-electric power. • Provide backup power to the critical ATR loads in the event of a loss of commercial power. • Replace obsolescent critical ATR power distribution equipment, e.g., switchgear, transformers, motor control centers, distribution panels. Completion of this and two other age-related projects (primary coolant pump and motor replacement and emergency firewater injection system replacement) will resolve major age related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the project pre-conceptual design identified several issues make the project a major modification: 1. Evaluation Criteria #2 (Footprint change). The addition of a new PC-4 structure to the ATR Facility to house safety-related SSCs requires careful attention to maintaining adherence to applicable engineering and nuclear safety design criteria (e.g., structural qualification, fire suppression) to ensure no adverse impacts to the safety-related functions of the housed equipment. 2. Evaluation Criteria #3 (Change of existing process). The change to the strategy for providing continuous reliable power to the safety-related emergency coolant pumps requires careful attention and analysis to ensure it meets a project primary object

  11. ATR-FTIR Spectroscopy in the Undergraduate Chemistry Laboratory: Part II--A Physical Chemistry Laboratory Experiment on Surface Adsorption

    ERIC Educational Resources Information Center

    Schuttlefield, Jennifer D.; Larsen, Sarah C.; Grassian, Vicki H.

    2008-01-01

    Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is a useful technique for measuring the infrared spectra of solids and liquids as well as probing adsorption on particle surfaces. The use of FTIR-ATR spectroscopy in organic and inorganic chemistry laboratory courses as well as in undergraduate research was presented…

  12. EFFECTS OF ATRAZINE (ATR), DEISOPROPYLATRAZINE (DIA), AND DIAMINOCHLOROTRIAZINE (DACT) ON THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS IN FEMALE RATS

    EPA Science Inventory

    Previously we reported that a single dose of ATR herbicide stimulated HPA axis activation in the male rat while its primary metabolite, DACT, did so to a lesser extent. In this study, we evaluated the effects of ATR, DACT, and an intermediate metabolite, DIA, on adrenocorticotrop...

  13. A synthetic lethal screen identifies ATR-inhibition as a novel therapeutic approach for POLD1-deficient cancers

    PubMed Central

    Hocke, Sandra; Guo, Yang; Job, Albert; Orth, Michael; Ziesch, Andreas; Lauber, Kirsten; De Toni, Enrico N; Gress, Thomas M.; Herbst, Andreas; Göke, Burkhard; Gallmeier, Eike

    2016-01-01

    The phosphoinositide 3-kinase-related kinase ATR represents a central checkpoint regulator and mediator of DNA-repair. Its inhibition selectively eliminates certain subsets of cancer cells in various tumor types, but the underlying genetic determinants remain enigmatic. Here, we applied a synthetic lethal screen directed against 288 DNA-repair genes using the well-defined ATR knock-in model of DLD1 colorectal cancer cells to identify potential DNA-repair defects mediating these effects. We identified a set of DNA-repair proteins, whose knockdown selectively killed ATR-deficient cancer cells. From this set, we further investigated the profound synthetic lethal interaction between ATR and POLD1. ATR-dependent POLD1 knockdown-induced cell killing was reproducible pharmacologically in POLD1-depleted DLD1 cells and a panel of other colorectal cancer cell lines by using chemical inhibitors of ATR or its major effector kinase CHK1. Mechanistically, POLD1 depletion in ATR-deficient cells caused caspase-dependent apoptosis without preceding cell cycle arrest and increased DNA-damage along with impaired DNA-repair. Our data could have clinical implications regarding tumor genotype-based cancer therapy, as inactivating POLD1 mutations have recently been identified in small subsets of colorectal and endometrial cancers. POLD1 deficiency might thus represent a predictive marker for treatment response towards ATR- or CHK1-inhibitors that are currently tested in clinical trials. PMID:26755646

  14. ATR-FTIR Spectroscopy in the Undergraduate Chemistry Laboratory: Part II--A Physical Chemistry Laboratory Experiment on Surface Adsorption

    ERIC Educational Resources Information Center

    Schuttlefield, Jennifer D.; Larsen, Sarah C.; Grassian, Vicki H.

    2008-01-01

    Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is a useful technique for measuring the infrared spectra of solids and liquids as well as probing adsorption on particle surfaces. The use of FTIR-ATR spectroscopy in organic and inorganic chemistry laboratory courses as well as in undergraduate research was presented…

  15. Effects of atrazine (ATR), deisopropylatrazine (DIA), Diaminochlorotriazine (DACT) on the hypothalamic-pituitary-adrenal (HPA) axis in female rats

    EPA Science Inventory

    We previously reported that a single dose of the herbicide ATR stimulated the HPA axis in the male rat while equimolar doses of its primary metabolite, DACT, had a minimal effect. In this study, we evaluated the effects of one or four daily doses of ATR, DACT, and an intermediat...

  16. Effects of atrazine (ATR), deisopropylatrazine (DIA), Diaminochlorotriazine (DACT) on the hypothalamic-pituitary-adrenal (HPA) axis in female rats

    EPA Science Inventory

    We previously reported that a single dose of the herbicide ATR stimulated the HPA axis in the male rat while equimolar doses of its primary metabolite, DACT, had a minimal effect. In this study, we evaluated the effects of one or four daily doses of ATR, DACT, and an intermediat...

  17. EFFECTS OF ATRAZINE (ATR), DEISOPROPYLATRAZINE (DIA), AND DIAMINOCHLOROTRIAZINE (DACT) ON THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS IN FEMALE RATS

    EPA Science Inventory

    Previously we reported that a single dose of ATR herbicide stimulated HPA axis activation in the male rat while its primary metabolite, DACT, did so to a lesser extent. In this study, we evaluated the effects of ATR, DACT, and an intermediate metabolite, DIA, on adrenocorticotrop...

  18. Micro-Attenuated Total Reflection Fourier Transform Infrared (Micro ATR FT-IR) Spectroscopic Imaging with Variable Angles of Incidence.

    PubMed

    Wrobel, Tomasz P; Vichi, Alessandra; Baranska, Malgorzata; Kazarian, Sergei G

    2015-10-01

    The control of the angle of incidence in attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopy allows for the probing of the sample at different depths of penetration of the evanescent wave. This approach has been recently coupled with macro-imaging capability using a diamond ATR accessory. In this paper, the design of optical apertures for the micro-germanium (Ge) ATR objective is presented for an FT-IR spectroscopic imaging microscope, allowing measurements with different angles of incidence. This approach provides the possibility of three-dimensional (3D) profiling in micro-ATR FT-IR imaging mode. The proof of principle results for measurements of polymer laminate samples at different angles of incidence confirm that controlling the depth of penetration is possible using a Ge ATR objective with added apertures.

  19. Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970

    PubMed Central

    Boucher, Diane M.; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A.; Milton, Sean; Murphy, Cheryl E.; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M.; Pollard, John R.

    2014-01-01

    Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients. PMID:25010037

  20. Multivariate analysis of ATR-FTIR spectra for assessment of oil shale organic geochemical properties

    USGS Publications Warehouse

    Washburn, Kathryn E.; Birdwell, Justin E.

    2013-01-01

    In this study, attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FTIR) was coupled with partial least squares regression (PLSR) analysis to relate spectral data to parameters from total organic carbon (TOC) analysis and programmed pyrolysis to assess the feasibility of developing predictive models to estimate important organic geochemical parameters. The advantage of ATR-FTIR over traditional analytical methods is that source rocks can be analyzed in the laboratory or field in seconds, facilitating more rapid and thorough screening than would be possible using other tools. ATR-FTIR spectra, TOC concentrations and Rock–Eval parameters were measured for a set of oil shales from deposits around the world and several pyrolyzed oil shale samples. PLSR models were developed to predict the measured geochemical parameters from infrared spectra. Application of the resulting models to a set of test spectra excluded from the training set generated accurate predictions of TOC and most Rock–Eval parameters. The critical region of the infrared spectrum for assessing S1, S2, Hydrogen Index and TOC consisted of aliphatic organic moieties (2800–3000 cm−1) and the models generated a better correlation with measured values of TOC and S2 than did integrated aliphatic peak areas. The results suggest that combining ATR-FTIR with PLSR is a reliable approach for estimating useful geochemical parameters of oil shales that is faster and requires less sample preparation than current screening methods.

  1. MATERNAL ATRAZINE (ATR) ALTERS HYPOTHALAMIC DOPAMINE (HYP-DA) AND SERUM PROLACTIN (SPRL) IN MALE PUPS

    EPA Science Inventory

    Maternal Atrazine (ATR) alters hypothalamic dopamine (HYP-DA) and serum prolactin (sPRL) in male pups. 1Christopher Langdale, 2Tammy Stoker and 2Ralph Cooper. 1 Dept. of Cell Biology, North Carolina State University College of Veterinary Medicine, Raleigh, NC. 2 Endocrinology ...

  2. Draft Genome Sequences of Neptuniibacter sp. Strains LFT 1.8 and ATR 1.1.

    PubMed

    Diéguez, A L; Romalde, J L

    2017-02-02

    We present the draft genomes of two strains previously identified as Neptuniibacter sp. LFT 1.8 (= CECT 8936 = DSM 100781) and ATR 1.1 (= CECT 8938 = DSM 100783) isolated from larvae of great scallops (Pecten maximus) and seawater, respectively. Both strains surely constitute two novel species in this genus, with putative applications for aromatic compound degradation.

  3. Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970.

    PubMed

    Hall, Amy B; Newsome, Dave; Wang, Yuxin; Boucher, Diane M; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A; Milton, Sean; Murphy, Cheryl E; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M; Pollard, John R

    2014-07-30

    Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients.

  4. Dynamic generation of artificial HRSAR imagery for ATR development and cockpit simulation

    NASA Astrophysics Data System (ADS)

    Seidel, Heiko; Stahl, Christoph; Knappe, Peter; Hurst, Peter

    2004-09-01

    Following the tendency of increasingly using imaging sensors in military aircraft, future combat airplane pilots will need onboard artificial intelligence for aiding them in image interpretation and target designation. This document presents a system which is able to simulate high-resolution artificial SAR imagery and thereby facilitates automatic target recognition (ATR) algorithm development. The system provides a comprehensive interface that allows dynamically requesting imagery depending on the location and heading of a simulated carrier platform. Landscapes, structures and target signatures are generated based on digital terrain data and target models. An assessment of dissimilar database preparations for sensor simulation was done with respect to the different properties of SAR imaging compared to optical imaging. The document presents selected results for specific landscape elements. Post-processing algorithms for overcoming weaknesses of digital terrain databases and improving image realism are presented. Simulated sensor imagery is useful in a wide range of applications, two of which are training of ATR algorithms and sensor simulation in flight simulation environments. Using an existing ATR method as an example, the applicability and the influences of synthetic imagery on ATR training are shown and first approaches on how to validate the correctness of the imagery are explained. The integration of the system into a flight simulator in the context of interfacing and control topics serves as a concluding example.

  5. Draft Genome Sequences of Neptuniibacter sp. Strains LFT 1.8 and ATR 1.1

    PubMed Central

    Diéguez, A. L.

    2017-01-01

    ABSTRACT We present the draft genomes of two strains previously identified as Neptuniibacter sp. LFT 1.8 (= CECT 8936 = DSM 100781) and ATR 1.1 (= CECT 8938 = DSM 100783) isolated from larvae of great scallops (Pecten maximus) and seawater, respectively. Both strains surely constitute two novel species in this genus, with putative applications for aromatic compound degradation. PMID:28153896

  6. MATERNAL ATRAZINE (ATR) ALTERS HYPOTHALAMIC DOPAMINE (HYP-DA) AND SERUM PROLACTIN (SPRL) IN MALE PUPS

    EPA Science Inventory

    Maternal Atrazine (ATR) alters hypothalamic dopamine (HYP-DA) and serum prolactin (sPRL) in male pups. 1Christopher Langdale, 2Tammy Stoker and 2Ralph Cooper. 1 Dept. of Cell Biology, North Carolina State University College of Veterinary Medicine, Raleigh, NC. 2 Endocrinology ...

  7. Nanocrystalline diamond sensor targeted for selective CRP detection: an ATR-FTIR spectroscopy study.

    PubMed

    Andersson, Per Ola; Viberg, Pernilla; Forsberg, Pontus; Nikolajeff, Fredrik; Österlund, Lars; Karlsson, Mikael

    2016-05-01

    Protein immobilization on functionalized fluorine-terminated nanocrystalline (NCD) films was studied by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy using an immobilization protocol developed to specifically bind C-reactive protein (CRP). Using an ATR-FTIR spectroscopy method employing a force-controlled anvil-type configuration, three critical steps of the ex situ CRP immobilization were analyzed. First, the NCD surface was passivated by deposition of a copolymer layer consisting of polyethylene oxide and polypropylene oxide. Second, a synthetic modified polypeptide binder with high affinity to CRP was covalently attached to the polymeric film. Third, CRP dissolved in aqueous buffer in concentrations of 10-20 μg/mL was added on the functionalized NCD surface. Both the amide I and II bands, due to the polypeptide binder and CRP, were clearly observed in ATR-FTIR spectra. CRP amide I bands were extracted from difference spectra and yielded bands that agreed well with the reported amide I band of free (non-bonded) CRP in solution. Thus, our results show that CRP retains its secondary structure when it is attached to the polypeptide binders. Compared to previous IR studies of CRP in solution, about 200 times lower concentration was applied in the present study. Graphical Abstract Direct non-destructive ATR-FTIR analysis of C-reactive protein (CRP) selectively bound to functionalized nanocrystalline diamond (NCD) sensor surface.

  8. U-shaped fiber-optic ATR sensor enhanced by silver nanoparticles for continuous glucose monitoring.

    PubMed

    Li, Dachao; Yu, Songlin; Sun, Changyue; Zou, Chongwei; Yu, Haixia; Xu, Kexin

    2015-10-15

    An implantable U-shaped fiber ATR sensor enhanced by silver nanoparticles on cylindrical surface was presented for continuous glucose monitoring to overcome the drawbacks of traditional glucose sensing technique based on enzyme electrodes. A U-shaped structure was addressed to increase effective optical length at limited implantable space to enhance the sensitivity of fiber ATR sensor. A novel method to fabricate silver nanoparticles on cylindrical surface of U-shaped fiber ATR sensor based on chemical reduction of its silver halide material directly without any preliminary nanoparticles synthesis and following covalent bond or self-assembly was proposed. Five glucose absorption wavelengths in the mid-infrared band were employed for specific glucose monitoring. The experimental results indicate that the sensitivity and resolution of the silver-nanoparticle-enhanced U-shaped fiber-optic ATR sensor are approximately three times those of a conventional one. The high sensitivity and low-noise performance makes it promising for in vivo glucose monitoring in the future clinical applications.

  9. Structural investigations of oriented membrane assemblies by FTIR-ATR spectroscopy

    NASA Astrophysics Data System (ADS)

    Fringeli, Urs Peter; Goette, Jeannette; Reiter, Gerald; Siam, Monira; Baurecht, Dieter

    1998-06-01

    In situ attenuated total reflection (ATR) Fourier transform (FT) spectroscopy is presented as an adequate tool for studying molecular structure and function of biomembranes. In this article emphasis was directed to the production of suitable model bilayer membranes for optimum mimicking of natural biomembranes, and to special FTIR ATR techniques to achieve enhanced selectivity as well as time resolved information on complex membrane assemblies. In this context, the preparation of supported bilayers according to the LB/vesicle method is presented and the use of such model membranes to build more complex assemblies, e.g. with creatine kinase, a surface bound enzyme, and alkaline phosphatase, a membrane anchored enzyme. A comprehensive summary of equations used for quantitative ATR spectroscopy is given and applied to determine the surface concentration and orientation of membrane bound molecules. The use of supported bilayers for drug membrane interaction studies is demonstrated by the local anesthetic dibucaine. Besides of structural information's, such studies result also thermodynamic date, such as adsorption isotherm and partition coefficient. A special ATR set-up for more precise background compensation is presented enabling the conversion of a single beam spectrometer into a pseudo double beam spectrometer. This optical component may be placed in the sample compartment of the spectrometer, and is referred to as single-beam-sample-reference (SBSR) attachment. Finally, a short theoretical introduction into time resolved modulation spectroscopy is given. Temperature modulated excitation of reversible conformational changes in the polypeptide poly-L-lysine and the enzyme RNase are shown as examples.

  10. Alternative Fuels

    EPA Pesticide Factsheets

    Alternative fuels include gaseous fuels such as hydrogen, natural gas, and propane; alcohols such as ethanol, methanol, and butanol; vegetable and waste-derived oils; and electricity. Overview of alternative fuels is here.

  11. Fuel pin

    DOEpatents

    Christiansen, David W.; Karnesky, Richard A.; Leggett, Robert D.; Baker, Ronald B.

    1989-10-03

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  12. Fuel pin

    DOEpatents

    Christiansen, David W.; Karnesky, Richard A.; Leggett, Robert D.; Baker, Ronald B.

    1989-01-01

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  13. Fuel pin

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  14. Fuel pin

    SciTech Connect

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  15. On0Line Fuel Failure Monitor for Fuel Testing and Monitoring of Gas Cooled Very High Temperature Reactor

    SciTech Connect

    Ayman I. Hawari; Mohamed A. Bourham

    2010-04-22

    IVery High Temperature Reactors (VHTR) utilize the TRISO microsphere as the fundamental fuel unit in the core. The TRISO microsphere (~ 1- mm diameter) is composed of a UO2 kernel surrounded by a porous pyrolytic graphite buffer, an inner pyrolytic graphite layer, a silicon carbide (SiC) coating, and an outer pyrolytic graphite layer. The U-235 enrichment of the fuel is expected to range from 4% – 10% (higher enrichments are also being considered). The layer/coating system that surrounds the UO2 kernel acts as the containment and main barrier against the environmental release of radioactivity. To understand better the behavior of this fuel under in-core conditions (e.g., high temperature, intense fast neutron flux, etc.), the US Department of Energy (DOE) is launching a fuel testing program that will take place at the Advanced Test Reactor (ATR) located at Idaho National Laboratory (INL). During this project North Carolina State University (NCSU) researchers will collaborate with INL staff for establishing an optimized system for fuel monitoring for the ATR tests. In addition, it is expected that the developed system and methods will be of general use for fuel failure monitoring in gas cooled VHTRs.

  16. Protein phosphatase 5 is necessary for ATR-mediated DNA repair

    SciTech Connect

    Kang, Yoonsung; Cheong, Hyang-Min; Lee, Jung-Hee; Song, Peter I.; Lee, Kwang-Ho; Kim, Sang-Yong; Jun, Jae Yeoul; You, Ho Jin

    2011-01-07

    Research highlights: {yields} Serine/threonine protein phosphatase 5 (PP5) has been shown to participate in ataxia telangiectasia-mutated (ATM)- and ATR (ATM- and Rad3-related)-mediated checkpoint pathways, which plays an important role in the DNA damage response and maintenance of genomic stability. {yields} However, it is not clear exactly how PP5 participates in this process. {yields} Our results indicate that PP5 is more closely related with ATR-mediated pathway than ATM-mediated pathway in DNA damage repair. -- Abstract: Several recent studies have shown that protein phosphatase 5 (PP5) participates in cell cycle arrest after DNA damage, but its roles in DNA repair have not yet been fully characterized. We investigated the roles of PP5 in the repair of ultraviolet (UV)- and neocarzinostatin (NCS)-induced DNA damage. The results of comet assays revealed different repair patterns in UV- and NCS-exposed U2OS-PS cells. PP5 is only essential for Rad3-related (ATR)-mediated DNA repair. Furthermore, the phosphorylation of 53BP1 and BRCA1, important mediators of DNA damage repair, and substrates of ATR and ATM decreased in U2OS-PS cells exposed to UV radiation. In contrast, the cell cycle arrest proteins p53, CHK1, and CHK2 were normally phosphorylated in U2OS and U2OS-PS cells exposed to UV radiation or treated with NCS. In view of these results, we suggest that PP5 plays a crucial role in ATR-mediated repair of UV-induced DNA damage.

  17. DNA-PKcs, ATM, and ATR Interplay Maintains Genome Integrity during Neurogenesis.

    PubMed

    Enriquez-Rios, Vanessa; Dumitrache, Lavinia C; Downing, Susanna M; Li, Yang; Brown, Eric J; Russell, Helen R; McKinnon, Peter J

    2017-01-25

    The DNA damage response (DDR) orchestrates a network of cellular processes that integrates cell-cycle control and DNA repair or apoptosis, which serves to maintain genome stability. DNA-PKcs (the catalytic subunit of the DNA-dependent kinase, encoded by PRKDC), ATM (ataxia telangiectasia, mutated), and ATR (ATM and Rad3-related) are related PI3K-like protein kinases and central regulators of the DDR. Defects in these kinases have been linked to neurodegenerative or neurodevelopmental syndromes. In all cases, the key neuroprotective function of these kinases is uncertain. It also remains unclear how interactions between the three DNA damage-responsive kinases coordinate genome stability, particularly in a physiological context. Here, we used a genetic approach to identify the neural function of DNA-PKcs and the interplay between ATM and ATR during neurogenesis. We found that DNA-PKcs loss in the mouse sensitized neuronal progenitors to apoptosis after ionizing radiation because of excessive DNA damage. DNA-PKcs was also required to prevent endogenous DNA damage accumulation throughout the adult brain. In contrast, ATR coordinated the DDR during neurogenesis to direct apoptosis in cycling neural progenitors, whereas ATM regulated apoptosis in both proliferative and noncycling cells. We also found that ATR controls a DNA damage-induced G2/M checkpoint in cortical progenitors, independent of ATM and DNA-PKcs. These nonoverlapping roles were further confirmed via sustained murine embryonic or cortical development after all three kinases were simultaneously inactivated. Thus, our results illustrate how DNA-PKcs, ATM, and ATR have unique and essential roles during the DDR, collectively ensuring comprehensive genome maintenance in the nervous system.

  18. Fuel pump

    SciTech Connect

    Bellis, P.D.; Nesselrode, F.

    1991-04-16

    This patent describes a fuel pump. It includes: a fuel reservoir member, the fuel reservoir member being formed with fuel chambers, the chambers comprising an inlet chamber and an outlet chamber, means to supply fuel to the inlet chamber, means to deliver fuel from the outlet chamber to a point of use, the fuel reservoir member chambers also including a bypass chamber, means interconnecting the bypass chamber with the outlet chamber; the fuel pump also comprising pump means interconnecting the inlet chamber and the outlet chamber and adapted to suck fuel from the fuel supply means into the inlet chamber, through the pump means, out the outlet chamber, and to the fuel delivery means; the bypass chamber and the pump means providing two substantially separate paths of fuel flow in the fuel reservoir member, bypass plunger means normally closing off the flow of fuel through the bypass chamber one of the substantially separate paths including the fuel supply means and the fuel delivery means when the bypass plunger means is closed, the second of the substantially separate paths including the bypass chamber when the bypass plunger means is open, and all of the chambers and the interconnecting means therebetween being configured so as to create turbulence in the flow of any fuel supplied to the outlet chamber by the pump means and bypassed through the bypass chamber and the interconnecting means.

  19. The ABC transporter ATR1 is necessary for efflux of the toxin cercosporin in the fungus Cercospora nicotianae.

    PubMed

    Amnuaykanjanasin, Alongkorn; Daub, Margaret E

    2009-02-01

    The Cercospora nicotianae mutant deficient for the CRG1 transcription factor has marked reductions in both resistance and biosynthesis of the toxin cercosporin. We cloned and sequenced full-length copies of two genes, ATR1 and CnCFP, previously identified from a subtractive library between the wild type (WT) and a crg1 mutant. ATR1 is an ABC transporter gene and has an open reading frame (ORF) of 4368bp with one intron. CnCFP encodes a MFS transporter with homology to Cercospora kikuchii CFP, previously implicated in cercosporin export, and has an ORF of 1975bp with three introns. Disruption of ATR1 indicated atr1-null mutants had dramatic reductions in cercosporin production (25% and 20% of WT levels) in solid and liquid cultures, respectively. The ATR1 disruptants also showed moderately higher sensitivity to cercosporin. Constitutive expression of ATR1 in the crg1 mutant restored cercosporin biosynthesis and moderately increased resistance. In contrast, CnCFP overexpression in the mutant did not restore toxin production, however, it moderately enhanced toxin resistance. The results together indicate ATR1 acts as a cercosporin efflux pump in this fungus and plays a partial role in resistance.

  20. A Synthetic Lethal Screen Identifies DNA Repair Pathways that Sensitize Cancer Cells to Combined ATR Inhibition and Cisplatin Treatments

    PubMed Central

    Mohni, Kareem N.; Thompson, Petria S.; Luzwick, Jessica W.; Glick, Gloria G.; Pendleton, Christopher S.; Lehmann, Brian D.; Pietenpol, Jennifer A.; Cortez, David

    2015-01-01

    The DNA damage response kinase ATR may be a useful cancer therapeutic target. ATR inhibition synergizes with loss of ERCC1, ATM, XRCC1 and DNA damaging chemotherapy agents. Clinical trials have begun using ATR inhibitors in combination with cisplatin. Here we report the first synthetic lethality screen with a combination treatment of an ATR inhibitor (ATRi) and cisplatin. Combination treatment with ATRi/cisplatin is synthetically lethal with loss of the TLS polymerase ζ and 53BP1. Other DNA repair pathways including homologous recombination and mismatch repair do not exhibit synthetic lethal interactions with ATRi/cisplatin, even though loss of some of these repair pathways sensitizes cells to cisplatin as a single-agent. We also report that ATRi strongly synergizes with PARP inhibition, even in homologous recombination-proficient backgrounds. Lastly, ATR inhibitors were able to resensitize cisplatin-resistant cell lines to cisplatin. These data provide a comprehensive analysis of DNA repair pathways that exhibit synthetic lethality with ATR inhibitors when combined with cisplatin chemotherapy, and will help guide patient selection strategies as ATR inhibitors progress into the cancer clinic. PMID:25965342

  1. Light water reactor mixed-oxide fuel irradiation experiment

    SciTech Connect

    Hodge, S.A.; Cowell, B.S.; Chang, G.S.; Ryskamp, J.M.

    1998-06-01

    The United States Department of Energy Office of Fissile Materials Disposition is sponsoring and Oak Ridge National Laboratory (ORNL) is leading an irradiation experiment to test mixed uranium-plutonium oxide (MOX) fuel made from weapons-grade (WG) plutonium. In this multiyear program, sealed capsules containing MOX fuel pellets fabricated at Los Alamos National Laboratory (LANL) are being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The planned experiments will investigate the utilization of dry-processed plutonium, the effects of WG plutonium isotopics on MOX performance, and any material interactions of gallium with Zircaloy cladding.

  2. Advanced Test Reactor National Scientific User Facility (ATR NSUF) Monthly Report November 2014

    SciTech Connect

    Soelberg, Renae

    2014-11-01

    Advanced Test Reactor National Scientific User Facility (ATR NSUF) Monthly Report November 2014 Highlights Rory Kennedy and Sarah Robertson attended the American Nuclear Society Winter Meeting and Nuclear Technology Expo in Anaheim, California, Nov. 10-13. ATR NSUF exhibited at the technology expo where hundreds of meeting participants had an opportunity to learn more about ATR NSUF. Dr. Kennedy briefed the Nuclear Engineering Department Heads Organization (NEDHO) on the workings of the ATR NSUF. • Rory Kennedy, James Cole and Dan Ogden participated in a reactor instrumentation discussion with Jean-Francois Villard and Christopher Destouches of CEA and several members of the INL staff. • ATR NSUF received approval from the NE-20 office to start planning the annual Users Meeting. The meeting will be held at INL, June 22-25. • Mike Worley, director of the Office of Innovative Nuclear Research (NE-42), visited INL Nov. 4-5. Milestones Completed • Recommendations for the Summer Rapid Turnaround Experiment awards were submitted to DOE-HQ Nov. 12 (Level 2 milestone due Nov. 30). Major Accomplishments/Activities • The University of California, Santa Barbara 2 experiment was unloaded from the GE-2000 at HFEF. The experiment specimen packs will be removed and shipped to ORNL for PIE. • The Terrani experiment, one of three FY 2014 new awards, was completed utilizing the Advanced Photon Source MRCAT beamline. The experiment investigated the chemical state of Ag and Pd in SiC shell of irradiated TRISO particles via X-ray Absorption Fine Structure (XAFS) spectroscopy. Upcoming Meetings/Events • The ATR NSUF program review meeting will be held Dec. 9-10 at L’Enfant Plaza. In addition to NSUF staff and users, NE-4, NE-5 and NE-7 representatives will attend the meeting. Awarded Research Projects Boise State University Rapid Turnaround Experiments (14-485 and 14-486) Nanoindentation and TEM work on the T91, HT9, HCM12A and 9Cr ODS specimens has been completed at

  3. Development of Metallic Fuels for Actinide Transmutation

    SciTech Connect

    Hayes, Steven Lowe; Fielding, Randall Sidney; Benson, Michael Timothy; Chichester, Heather Jean MacLean; Carmack, William Jonathan

    2015-09-01

    Research and development activities on metallic fuels are focused on their potential use for actinide transmutation in future sodium fast reactors. As part of this application, there is also a need for a near zero-loss fabrication process and a desire to demonstrate a multifold increase in burnup potential. The incorporation of Am and Np into the traditional U-20Pu-10Zr metallic fuel alloy was demonstrated in the US during the Integral Fast Reactor Program of the 1980’s and early 1990’s. However, the conventional counter gravity injection casting method performed under vacuum, previously used to fabricate these metallic fuel alloys, was not optimized for mitigating loss of the volatile Am constituent in the casting charge; as a result, approximately 40% of the Am casting charge failed to be incorporated into the as-cast fuel alloys. Fabrication development efforts of the past few years have pursued an optimized bottom-pour casting method to increase utilization of the melted charge to near 100%, and a differential pressure casting approach, performed under an argon overpressure, has been demonstrated to result in essentially no loss of Am due to volatilization during fabrication. In short, a path toward zero-loss fabrication of metallic fuels including minor actinides has been shown to be feasible. Irradiation testing of advanced metallic fuel alloys in the Advanced Test Reactor (ATR) has been underway since 2003. Testing in the ATR is performed inside of cadmium-shrouded positions to remove >99% of the thermal flux incident on the test fuels, resulting in an epi-thermal driven fuel test that is free from gross flux depression and producing an essentially prototypic radial temperature profile inside the fuel rodlets. To date, three irradiation test series (AFC-1,2,3) have been completed. Over 20 different metallic fuel alloys have been tested to burnups as high as 30% with constituent compositions of Pu up to 30%, Am up to 12%, Np up to 10%, and Zr between 10

  4. Nuclear Fuels & Materials Spotlight Volume 4

    SciTech Connect

    I. J. van Rooyen,; T. M. Lillo; Y. Q. WU; P.A. Demkowicz; L. Scott; D.M. Scates; E. L. Reber; J. H. Jackson; J. A. Smith; D.L. Cottle; B.H. Rabin; M.R. Tonks; S.B. Biner; Y. Zhang; R.L. Williamson; S.R. Novascone; B.W. Spencer; J.D. Hales; D.R. Gaston; C.J. Permann; D. Anders; S.L. Hayes; P.C. Millett; D. Andersson; C. Stanek; R. Ali; S.L. Garrett; J.E. Daw; J.L. Rempe; J. Palmer; B. Tittmann; B. Reinhardt; G. Kohse; P. Ramuhali; H.T. Chien; T. Unruh; B.M. Chase; D.W. Nigg; G. Imel; J. T. Harris

    2014-04-01

    As the nation's nuclear energy laboratory, Idaho National Laboratory brings together talented people and specialized nuclear research capability to accomplish our mission. This edition of the Nuclear Fuels and Materials Division Spotlight provides an overview of some of our recent accomplishments in research and capability development. These accomplishments include: • The first identification of silver and palladium migrating through the SiC layer in TRISO fuel • A description of irradiation assisted stress corrosion testing capabilities that support commercial light water reactor life extension • Results of high-temperature safety testing on coated particle fuels irradiated in the ATR • New methods for testing the integrity of irradiated plate-type reactor fuel • Description of a 'Smart Fuel' concept that wirelessly provides real time information about changes in nuclear fuel properties and operating conditions • Development and testing of ultrasonic transducers and real-time flux sensors for use inside reactor cores, and • An example of a capsule irradiation test. Throughout Spotlight, you'll find examples of productive partnerships with academia, industry, and government agencies that deliver high-impact outcomes. The work conducted at Idaho National Laboratory helps to spur innovation in nuclear energy applications that drive economic growth and energy security. We appreciate your interest in our work here at INL, and hope that you find this issue informative.

  5. Attenuated total reflection infrared spectroscopy (ATR-IR) as an in situ technique for dissolution studies.

    PubMed

    Kassis, Abe; Bhawtankar, Vrushali M; Sowa, John R

    2010-11-02

    Dissolution studies are critical tests for measuring the performance of a drug product. We have developed a novel technique using in situ ATR-IR spectroscopy to monitor dissolutions of pharmaceutical drug products. The accuracy of this technique is +/-3% relative to HPLC using salicylic acid calibrator tablets and acetaminophen OTC tablets. This novel approach also gives the research laboratory the capability of analyzing individual ingredients in multiple tablets; for example, individual components of salicylic acid and acetaminophen tablets are easily distinguished. In addition, the individual ingredients of a multi-component tablet containing acetylsalicylic acid and acetaminophen are readily distinguished. The ATR-IR system was found to have good sensitivity and can analyze samples as low as 0.03 mg/ml. With improved sensitivity, this is a promising method for monitoring dissolution of pharmaceutical tablets with an excellent in situ capability for distinguishing individual components. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  6. Optimization of a Multi-Stage ATR System for Small Target Identification

    NASA Technical Reports Server (NTRS)

    Lin, Tsung-Han; Lu, Thomas; Braun, Henry; Edens, Western; Zhang, Yuhan; Chao, Tien- Hsin; Assad, Christopher; Huntsberger, Terrance

    2010-01-01

    An Automated Target Recognition system (ATR) was developed to locate and target small object in images and videos. The data is preprocessed and sent to a grayscale optical correlator (GOC) filter to identify possible regionsof- interest (ROIs). Next, features are extracted from ROIs based on Principal Component Analysis (PCA) and sent to neural network (NN) to be classified. The features are analyzed by the NN classifier indicating if each ROI contains the desired target or not. The ATR system was found useful in identifying small boats in open sea. However, due to "noisy background," such as weather conditions, background buildings, or water wakes, some false targets are mis-classified. Feedforward backpropagation and Radial Basis neural networks are optimized for generalization of representative features to reduce false-alarm rate. The neural networks are compared for their performance in classification accuracy, classifying time, and training time.

  7. ATR-A1 irradiation experiment on vanadium alloys and low activation steels

    SciTech Connect

    Tasi, H.; Strain, R.V.; Gomes, I.; Hins, A.G.; Smith, D.L.

    1996-04-01

    To study the mechanical properties of vanadium alloys under neutron irradiation at low temperatures, an experiment was designed and constructed for irradiation in the Advanced Test Reactor (ATR). The experiment contained Charpy, tensile, compact tension, TEM, and creep specimens of vanadium alloys. It also contained limited low-activation ferritic steel specimens as part of the collaborative agreement with Monbusho of Japan. The design irradiation temperatures for the vanadium alloy specimens in the experiment are {approx}200 and 300{degrees}C, achieved with passive gap-gap sizing and fill gas blending. To mitigate vanadium-to-chromium transmutation from the thermal neutron flux, the test specimens are contained inside gadolinium flux filters. All specimens are lithium-bonded. The irradiation started in Cycle 108A (December 3, 1995) and is expected to have a duration of three ATR cycles and a peak influence of 4.4 dpa.

  8. Radiation Measurements Laboratory (RML) calibration and assessment of the ATR SPING-3 stack effluent monitor

    SciTech Connect

    Koeppen, L.D.; Rogers, J.W.; Simpson, O.D.

    1983-12-01

    An evaluation, calibration and assessment of the Eberline SPING-3 ATR stack effluent monitor was conducted. This unit which monitors particulate, iodine and noble gas effluents was producing abnormal results following the initial installation and operational testing. The purposes of this work were to find the causes of the abnormal results and correct them if possible; check the calibrations and adjust them if necessary; and to provide a better in-depth understanding of what the unit is monitoring and how well it performs under this application. Results have shown that there were some problems associated with the unit as initially installed and tested. These problems have been identified and suggested alternatives shown, the monitor was found to be applicable to some extent under the current conditions. The calibrations have been checked and adjustments made. More operation testing and evaluation is needed to assess how well this works under a variety of ATR operating conditions. 2 references, 10 figures, 3 tables. (ACR)

  9. Employing polyethylene as contacting agent between ATR-crystals and solid samples with hard surfaces

    NASA Astrophysics Data System (ADS)

    Ivanovski, Vladimir; Mayerhöfer, Thomas G.; Popp, Jürgen

    2009-04-01

    Using a single crystal of fresnoite (Ba 2TiSiO 8), we demonstrate that polyethylene (PE) can be used as a contacting agent to enable the recording of ATR-spectra of materials with hard surfaces. The performance of our method is compared with the standard according to literature where CS 2 is used as an immersion liquid. A Harrick Seagull cell, equipped with a ZnSe semi-sphere ATR-crystal has been used in measuring s- and p-polarized spectra at different incidence angles. The experimental results were compared with model calculations based on the dielectric function tensor of fresnoite. The comparison reveals advantages of our method compared to the use of CS 2 like: closer resemblance between experimental and modeled spectra, repeatability and persistent optical contact. Moreover, our technique is easier to use.

  10. Structure-Based Drug Design of Novel, Potent, and Selective Azabenzimidazoles (ABI) as ATR Inhibitors

    PubMed Central

    2014-01-01

    Compound 13 was discovered through morphing of the ATR biochemical HTS hit 1. The ABI series was potent and selective for ATR. Incorporation of a 6-azaindole afforded a marked increase in cellular potency but was associated with poor PK and hERG ion channel inhibition. DMPK experiments established that CYP P450 and AO metabolism in conjunction with Pgp and BCRP efflux were major causative mechanisms for the observed PK. The series also harbored the CYP3A4 TDI liability driven by the presence of both a morpholine and an indole moiety. Incorporation of an adjacent fluorine or nitrogen into the 6-azaindole addressed many of the various medicinal chemistry issues encountered. PMID:25589928

  11. Performance models for hypothesis-level fusion of multilook SAR ATR

    NASA Astrophysics Data System (ADS)

    Snyder, William C.; Ettinger, Gil J.

    2003-09-01

    We present the theoretical basis and a top level system design for estimating and predicting the uncertainty from single and multiple-look model-based automatic target recognition (ATR). Uncertainty estimation is used in decision making based on the probability of correct identification and the probability of a false alarm for a given ATR result. Uncertainty prediction provides a basis for asset management by establishing the value of additional looks at a target. A number of first principles theoretical models have been developed based on information theory and physics. These generally bound performance under idealized conditions. Our hypothesis test approach is designed to support operational uncertainty estimation and prediction based on statistics from parameterized models, simulations, and measurements. A significant challenge that we investigate is generating the probability density of the test statistic under the null hypothesis, which contains un-modeled types and natural clutter. Another challenge we address is establishing uncertainty under multiple look fusion.

  12. Optimization of Adaboost Algorithm for Sonar Target Detection in a Multi-Stage ATR System

    NASA Technical Reports Server (NTRS)

    Lin, Tsung Han (Hank)

    2011-01-01

    JPL has developed a multi-stage Automated Target Recognition (ATR) system to locate objects in images. First, input images are preprocessed and sent to a Grayscale Optical Correlator (GOC) filter to identify possible regions-of-interest (ROIs). Second, feature extraction operations are performed using Texton filters and Principal Component Analysis (PCA). Finally, the features are fed to a classifier, to identify ROIs that contain the targets. Previous work used the Feed-forward Back-propagation Neural Network for classification. In this project we investigate a version of Adaboost as a classifier for comparison. The version we used is known as GentleBoost. We used the boosted decision tree as the weak classifier. We have tested our ATR system against real-world sonar images using the Adaboost approach. Results indicate an improvement in performance over a single Neural Network design.

  13. Phylogeny of cultivated and wild wheat species using ATR-FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Demir, Pinar; Onde, Sertac; Severcan, Feride

    2015-01-01

    Within the last decade, an increasing amount of genetic data has been used to clarify the problems inherent in wheat taxonomy. The techniques for obtaining and analyzing these data are not only cumbersome, but also expensive and technically demanding. In the present study, we introduce infrared spectroscopy as a method for a sensitive, rapid and low cost phylogenetic analysis tool for wheat seed samples. For this purpose, 12 Triticum and Aegilops species were studied by Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. Hierarchical cluster analysis and principal component analysis clearly revealed that the lignin band (1525-1505 cm-1) discriminated the species at the genus level. However, the species were clustered according to their genome commonalities when the whole spectra were used (4000-650 cm-1). The successful differentiation of Triticum and its closely related genus Aegilops clearly demonstrated the power of ATR-FTIR spectroscopy as a suitable tool for phylogenetic research.

  14. Coupling of phonon-polariton modes at dielectric-dielectric interfaces by the ATR technique

    NASA Astrophysics Data System (ADS)

    Cocoletzi, G. H.; Olvera Hernández, J.; Martínez Montes, G.

    1989-08-01

    We report the calculated ATR dispersion relation of the interface phonon-polariton modes in the prism-dielectric-dielectric configuration. Comparison of electromagnetic dispersion relations (EMDR) with the ATR dispersion relations are presented for three different interfaces: I) GaAs/GaP, II) CdF2/CaF2 and III) CaF2/GaP in two propagation windows, using the Otto and Kretschmann geometries for p-polarized light. We have studied the three cases using angle and frequency scans for each window and geometry. The results indicate that it is possible to excite and detect phonon-polariton modes at the dielectric-dielectric interface.

  15. Structure-Based Drug Design of Novel, Potent, and Selective Azabenzimidazoles (ABI) as ATR Inhibitors.

    PubMed

    Barsanti, Paul A; Pan, Yue; Lu, Yipin; Jain, Rama; Cox, Matthew; Aversa, Robert J; Dillon, Michael P; Elling, Robert; Hu, Cheng; Jin, Xianming; Knapp, Mark; Lan, Jiong; Ramurthy, Savithri; Rudewicz, Patrick; Setti, Lina; Subramanian, Sharadha; Mathur, Michelle; Taricani, Lorena; Thomas, George; Xiao, Linda; Yue, Qin

    2015-01-08

    Compound 13 was discovered through morphing of the ATR biochemical HTS hit 1. The ABI series was potent and selective for ATR. Incorporation of a 6-azaindole afforded a marked increase in cellular potency but was associated with poor PK and hERG ion channel inhibition. DMPK experiments established that CYP P450 and AO metabolism in conjunction with Pgp and BCRP efflux were major causative mechanisms for the observed PK. The series also harbored the CYP3A4 TDI liability driven by the presence of both a morpholine and an indole moiety. Incorporation of an adjacent fluorine or nitrogen into the 6-azaindole addressed many of the various medicinal chemistry issues encountered.

  16. Achieving safety/risk goals for less ATR backup power upgrades

    SciTech Connect

    Atkinson, S.A.

    1995-10-01

    The Advanced Test Reactor probabilistic risk assessment for internal fire and flood events defined a relatively high risk for a total loss of electric power possibly leading to core damage. Backup power sources were disabled due to fire and flooding in the diesel generator area with propagation of the flooding to a common switchgear room. The ATR risk assessment was employed to define options for relocation of backup power system components to achieve needed risk reduction while minimizing costs. The risk evaluations were performed using sensitivity studies and importance measures. The risk-based evaluations of relocation options for backup power systems saved over $3 million from what might have been otherwise considered {open_quotes}necessary{close_quotes} for safety/risk improvement. The ATR experience shows that the advantages of a good risk assessment are to define risk significance, risk specifics, and risk solutions which enable risk goals to be achieved at the lowest cost.

  17. Deletion of the Developmentally Essential Gene ATR in Adult Mice Leads to Age-Related Phenotypes and Stem Cell Loss

    PubMed Central

    Ruzankina, Yaroslava; Pinzon-Guzman, Carolina; Asare, Amma; Ong, Tony; Pontano, Laura; Cotsarelis, George; Zediak, Valerie P.; Velez, Marielena; Bhandoola, Avinash; Brown, Eric J.

    2010-01-01

    Summary Developmental abnormalities, cancer and premature aging each have been linked to defects in the DNA damage response (DDR). Mutations in the ATR checkpoint regulator cause developmental defects in mice (pre-gastrulation lethality) and humans (Seckel syndrome). Herein we show that eliminating ATR in adult mice leads to defects in tissue homeostasis and the rapid appearance of age-related phenotypes, such as hair graying, alopecia, kyphosis, osteoporosis, thymic involution, fibrosis and other abnormalities. Histological and genetic analyses indicate that ATR deletion causes acute cellular loss in tissues where continuous cell proliferation is required for maintenance. Importantly, thymic involution and alopecia and hair graying in ATR knockout mice were associated with dramatic reductions in tissue-specific stem and progenitor cells and exhaustion of tissue renewal and homeostatic capacity. In aggregate, these studies suggest that reduced regenerative capacity in adults via deletion of a developmentally essential DDR gene is sufficient to cause characteristics of premature aging. PMID:18371340

  18. Robust Multi-Look HRR ATR Investigation through Decision-Level Fusion Evaluation

    DTIC Science & Technology

    2008-07-01

    algorithms through multilook assessments to assess relative fusion performance gains. Keywords: ATR, Information Fusion, HRR, eigen-value, SVD, Fusion...reason, many surveillance systems incorporate High Range Resolution (HRR) radar and synthetic aperture radar ( SAR ) modes to be able to capture moving...Stationary Automatic Target Recognition (MSTAR) data set [11] that provides SAR collections, and the ImageFusion.org site that contains electro

  19. ATR-FTIR spectroscopy and spectroscopic imaging of solvent and permeant diffusion across model membranes.

    PubMed

    McAuley, W J; Lad, M D; Mader, K T; Santos, P; Tetteh, J; Kazarian, S G; Hadgraft, J; Lane, M E

    2010-02-01

    The uptake and diffusion of solvents across polymer membranes is important in controlled drug delivery, effects on drug uptake into, for example, infusion bags and containers, as well as transport across protective clothing. Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy has been used to monitor the effects of different solvents on the diffusion of a model compound, 4-cyanophenol (CNP) across silicone membrane and on the equilibrium concentration of CNP obtained in the membrane following diffusion. ATR-FTIR spectroscopic imaging of membrane diffusion was used to gain an understanding of when the boundary conditions applied to Fick's second law, used to model the diffusion of permeants across the silicone membrane do not hold. The imaging experiments indicated that when the solvent was not taken up appreciably into the membrane, the presence of discrete solvent pools between the ATR crystal and the silicone membrane can affect the diffusion profile of the permeant. This effect is more significant if the permeant has a high solubility in the solvent. In contrast, solvents that are taken up into the membrane to a greater extent, or those where the solubility of the permeant in the vehicle is relatively low, were found to show a good fit to the diffusion model. As such these systems allow the ATR-FTIR spectroscopic approach to give mechanistic insight into how the particular solvents enhance permeation. The solubility of CNP in the solvent and the uptake of the solvent into the membrane were found to be important influences on the equilibrium concentration of the permeant obtained in the membrane following diffusion. In general, solvents which were taken up to a significant extent into the membrane and which caused the membrane to swell increased the diffusion coefficient of the permeant in the membrane though other factors such as solvent viscosity may also be important.

  20. Applications of diamond crystal ATR FTIR spectroscopy to the characterization of ambers.

    PubMed

    Guiliano, Michel; Asia, Laurence; Onoratini, Gérard; Mille, Gilbert

    2007-08-01

    Diamond crystal ATR FTIR spectroscopy is a rapid technique with virtually no sample preparation which requires small sample amounts and showed potential in the study of ambers. FTIR spectra of ambers present discriminating patterns and can be used to distinguish amber from immature resins as copal, to determine local or Baltic origin of archaeological ambers and to detect most of the falsifications encountered in the amber commercialisation.

  1. ATR-FTIR spectroscopy and chemometrics: An interesting tool to discriminate and characterize counterfeit medicines.

    PubMed

    Custers, D; Cauwenbergh, T; Bothy, J L; Courselle, P; De Beer, J O; Apers, S; Deconinck, E

    2015-08-10

    Counterfeit medicines pose a huge threat to public health worldwide. High amounts of counterfeit pharmaceuticals enter the European market and therefore detection of these products is essential. Attenuated Total Reflection Fourier-Transform infrared spectroscopy (ATR-FTIR) might be useful for the screening of counterfeit medicines since it is easy to use and little sample preparation is required. Furthermore, this approach might be helpful to customs to obtain a first evaluation of suspected samples. This study proposes a combination of ATR-FTIR and chemometrics to discriminate and classify counterfeit medicines. A sample set, containing 209 samples in total, was analyzed using ATR-FTIR and the obtained spectra were used as fingerprints in the chemometric data-analysis which included Principal Component Analysis (PCA), k-Nearest Neighbours (k-NN), Classification and Regression Trees (CART) and Soft Independent Modelling of Class Analogy (SIMCA). First it was verified whether the mentioned techniques are capable to distinguish samples containing different active pharmaceutical ingredients (APIs). PCA showed a clear tendency of discrimination based on the API present; k-NN, CART and SIMCA were capable to create suitable prediction models based on the presence of different APIs. However k-NN performs the least while SIMCA performs the best. Secondly, it was tested whether these three models could be expanded to discriminate between genuine and counterfeit samples as well. k-NN was not able to make the desired discrimination and therefore it was not useful. CART performed better but also this model was less suited. SIMCA, on the other hand, resulted in a model with a 100% correct discrimination between genuine and counterfeit drugs. This study shows that chemometric analysis of ATR-FTIR fingerprints is a valuable tool to discriminate genuine from counterfeit samples and to classify counterfeit medicines. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. The Conference Proceedings of the 2003 Air Transport Research Society (ATRS) World Conference, Volume 3

    NASA Technical Reports Server (NTRS)

    Bowen, Brent (Editor); Gudmundsson, Sveinn (Editor); Oum, Tae (Editor)

    2003-01-01

    Volume 3 of the 2003 Air Transport Reserch Society (ATRS) World Conference includes papers on topics relevant to airline operations worldwide. Specific topics include: European Union and civil aviation regimens;simulating decision making in airline operations, passenger points of view on convenient airports; route monopolies and nonlinear pricing; cooperation among airports in Europe; fleet modernizaiton in Brazil;the effects of deregulation on the growth of air transportation in Europe and the United States.

  3. MODELING ASSUMPTIONS FOR THE ADVANCED TEST REACTOR FRESH FUEL SHIPPING CONTAINER

    SciTech Connect

    Rick J. Migliore

    2009-09-01

    The Advanced Test Reactor Fresh Fuel Shipping Container (ATR FFSC) is currently licensed per 10 CFR 71 to transport a fresh fuel element for either the Advanced Test Reactor, the University of Missouri Research Reactor (MURR), or the Massachusetts Institute of Technology Research Reactor (MITR-II). During the licensing process, the Nuclear Regulatory Commission (NRC) raised a number of issues relating to the criticality analysis, namely (1) lack of a tolerance study on the fuel and packaging, (2) moderation conditions during normal conditions of transport (NCT), (3) treatment of minor hydrogenous packaging materials, and (4) treatment of potential fuel damage under hypothetical accident conditions (HAC). These concerns were adequately addressed by modifying the criticality analysis. A tolerance study was added for both the packaging and fuel elements, full-moderation was included in the NCT models, minor hydrogenous packaging materials were included, and fuel element damage was considered for the MURR and MITR-II fuel types.

  4. Diesel fuel to dc power: Navy & Marine Corps Applications

    SciTech Connect

    Bloomfield, D.P.

    1996-12-31

    During the past year Analytic Power has tested fuel cell stacks and diesel fuel processors for US Navy and Marine Corps applications. The units are 10 kW demonstration power plants. The USN power plant was built to demonstrate the feasibility of diesel fueled PEM fuel cell power plants for 250 kW and 2.5 MW shipboard power systems. We designed and tested a ten cell, 1 kW USMC substack and fuel processor. The complete 10 kW prototype power plant, which has application to both power and hydrogen generation, is now under construction. The USN and USMC fuel cell stacks have been tested on both actual and simulated reformate. Analytic Power has accumulated operating experience with autothermal reforming based fuel processors operating on sulfur bearing diesel fuel, jet fuel, propane and natural gas. We have also completed the design and fabrication of an advanced regenerative ATR for the USMC. One of the significant problems with small fuel processors is heat loss which limits its ability to operate with the high steam to carbon ratios required for coke free high efficiency operation. The new USMC unit specifically addresses these heat transfer issues. The advances in the mill programs have been incorporated into Analytic Power`s commercial units which are now under test.

  5. Advanced Test Reactor LEU Fuel Conversion Feasibility Study (2006 Annual Report)

    SciTech Connect

    Gray S. Chang; Richard G. Ambrosek; Misti A. Lillo

    2006-12-01

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth with a maximum unperturbed thermal neutron flux rating of 1.0 x 1015 n/cm2–s. Because of these operating parameters, and the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuel cycle burnup comparison analysis. Using the current HEU U 235 enrichment of 93.0 % as a baseline, an analysis can be performed to determine the low-enriched uranium (LEU) density and U-235 enrichment required in the fuel meat to yield an equivalent K-eff between the HEU core and the LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the U-235 loading in the LEU core, such that the differences in K-eff and heat profile between the HEU and LEU core can be minimized for operation at 125 EFPD with a total core power of 115 MW. The depletion methodology, Monte-Carlo coupled with ORIGEN2 (MCWO), was used to calculate K-eff versus EFPDs. The MCWO-calculated results for the LEU case demonstrated adequate excess reactivity such that the K-eff versus EFPDs plot is similar in shape to the reference ATR HEU case. The LEU core conversion feasibility study can also be used to optimize the U-235 content of each fuel plate, so that the relative radial fission heat flux profile is bounded by the reference ATR HEU case. The detailed radial, axial, and azimuthal heat flux profiles of the HEU and optimized LEU cases have been investigated. However, to demonstrate that the LEU core fuel cycle performance can

  6. Advanced Test Reactor LEU Fuel Conversion Feasibility Study -- 2006 Annual Report

    SciTech Connect

    G. S. Chang; R. G. Ambrosek

    2006-10-01

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the U.S. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth with a maximum unperturbed thermal neutron flux rating of 1.0 x 1015 n/cm2–s. Because of these operating parameters, and the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuel cycle burnup comparison analysis. Using the current HEU U-235 enrichment of 93.0 % as a baseline, an analysis can be performed to determine the low-enriched uranium (LEU) density and U 235 enrichment required in the fuel meat to yield an equivalent Keff between the HEU core and a LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the U 235 loading in the LEU core, such that the differences in Keff and heat profile between the HEU and LEU core can be minimized for operation at 125 EFPD with a total core power of 115 MW. The Monte-Carlo coupled with ORIGEN2 (MCWO) depletion methodology was used to calculate Keff versus EFPDs. The MCWO-calculated results for the LEU case demonstrated adequate excess reactivity such that the Keff versus EFPDs plot is similar in shape to the reference ATR HEU case. The LEU core conversion feasibility study can also be used to optimize the U-235 content of each fuel plate, so that the relative radial fission heat flux profile is bounded by the reference ATR HEU case. The detailed radial, axial, and azimuthal heat flux profiles of the HEU and optimized LEU cases have been investigated. However, to demonstrate that the LEU core fuel cycle performance can meet the UFSAR

  7. Identification and evaluation of a potent novel ATR inhibitor, NU6027, in breast and ovarian cancer cell lines

    PubMed Central

    Peasland, A; Wang, L-Z; Rowling, E; Kyle, S; Chen, T; Hopkins, A; Cliby, W A; Sarkaria, J; Beale, G; Edmondson, R J; Curtin, N J

    2011-01-01

    Background: The ataxia telangiectasia mutated and Rad3-related kinase (ATR) has a key role in the signalling of stalled replication forks and DNA damage to cell cycle checkpoints and DNA repair. It has long been recognised as an important target for cancer therapy but inhibitors have proved elusive. As NU6027, originally developed as a CDK2 inhibitor, potentiated cisplatin in a CDK2-independent manner we postulated that it may inhibit ATR. Methods: Cellular ATR kinase activity was determined by CHK1 phosphorylation in human fibroblasts with inducible dominant-negative ATR-kinase dead expression and human breast cancer MCF7 cells. Cell cycle effects and chemo- and radiopotentiation by NU6027 were determined in MCF7 cells and the role of mismatch repair and p53 was determined in isogenically matched ovarian cancer A2780 cells. Results: NU6027 is a potent inhibitor of cellular ATR activity (IC50=6.7 μ) and enhanced hydroxyurea and cisplatin cytotoxicity in an ATR-dependent manner. NU6027 attenuated G2/M arrest following DNA damage, inhibited RAD51 focus formation and increased the cytotoxicity of the major classes of DNA-damaging anticancer cytotoxic therapy but not the antimitotic, paclitaxel. In A2780 cells sensitisation to cisplatin was greatest in cells with functional p53 and mismatch repair (MMR) and sensitisation to temozolomide was greatest in p53 mutant cells with functional MMR. Importantly, NU6027 was synthetically lethal when DNA single-strand break repair is impaired either through poly(ADP-ribose) polymerase (PARP) inhibition or defects in XRCC1. Conclusion: NU6027 inhibits ATR, impairing G2/M arrest and homologous recombination thus increasing sensitivity to DNA-damaging agents and PARP inhibitors. It provides proof of concept data for clinical development of ATR inhibitors. PMID:21730979

  8. ATR-X syndrome in two siblings with a novel mutation (c.6718C>T mutation in exon 31)

    PubMed Central

    Thakur, Seema; Ishrie, Mala; Saxena, Renu; Danda, Sumita; Linda, Rose; Viswabandya, Auro; Verma, I.C.

    2011-01-01

    ATR-X syndrome is an X-linked mental retardation syndrome characterized by mental retardation, alpha thalassaemia and distinct facial features which include microcephaly, frontal hair upsweep, epicanthic folds, small triangular nose, midface hypoplasia and carp-shaped mouth. Here we report two brothers with clinical features of ATR-X syndrome, in whom a novel missense (C>T) mutation was identified in exon 31 of the ATRX gene. PMID:22089611

  9. Resistance to PARP inhibitors by SLFN11 inactivation can be overcome by ATR inhibition

    PubMed Central

    Murai, Junko; Feng, Ying; Yu, Guoying K.; Ru, Yuanbin; Tang, Sai-Wen; Shen, Yuqiao; Pommier, Yves

    2016-01-01

    Poly(ADP-ribose) polymerase inhibitors (PARPIs) kill cancer cells by trapping PARP1 and PARP2. Talazoparib, the most potent PARPI inhibitor (PARPI), exhibits remarkable selectivity among the NCI-60 cancer cell lines beyond BRCA inactivation. Our genomic analyses reveal high correlation between response to talazoparib and Schlafen 11 (SLFN11) expression. Causality was established in four isogenic SLFN11-positive and -negative cell lines and extended to olaparib. Response to the talazoparib-temozolomide combination was also driven by SLFN11 and validated in 36 small cell lung cancer cell lines, and in xenograft models. Resistance in SLFN11-deficient cells was caused neither by impaired drug penetration nor by activation of homologous recombination. Rather, SLFN11 induced irreversible and lethal replication inhibition, which was independent of ATR-mediated S-phase checkpoint. The resistance to PARPIs by SLFN11 inactivation was overcome by ATR inhibition, mechanistically because SLFN11-deficient cells solely rely on ATR activation for their survival under PARPI treatment. Our study reveals that SLFN11 inactivation, which is common (~45%) in cancer cells, is a novel and dominant resistance determinant to PARPIs. PMID:27708213

  10. Resistance to PARP inhibitors by SLFN11 inactivation can be overcome by ATR inhibition.

    PubMed

    Murai, Junko; Feng, Ying; Yu, Guoying K; Ru, Yuanbin; Tang, Sai-Wen; Shen, Yuqiao; Pommier, Yves

    2016-11-22

    Poly(ADP-ribose) polymerase inhibitors (PARPIs) kill cancer cells by trapping PARP1 and PARP2. Talazoparib, the most potent PARPI inhibitor (PARPI), exhibits remarkable selectivity among the NCI-60 cancer cell lines beyond BRCA inactivation. Our genomic analyses reveal high correlation between response to talazoparib and Schlafen 11 (SLFN11) expression. Causality was established in four isogenic SLFN11-positive and -negative cell lines and extended to olaparib. Response to the talazoparib-temozolomide combination was also driven by SLFN11 and validated in 36 small cell lung cancer cell lines, and in xenograft models. Resistance in SLFN11-deficient cells was caused neither by impaired drug penetration nor by activation of homologous recombination. Rather, SLFN11 induced irreversible and lethal replication inhibition, which was independent of ATR-mediated S-phase checkpoint. The resistance to PARPIs by SLFN11 inactivation was overcome by ATR inhibition, mechanistically because SLFN11-deficient cells solely rely on ATR activation for their survival under PARPI treatment. Our study reveals that SLFN11 inactivation, which is common (~45%) in cancer cells, is a novel and dominant resistance determinant to PARPIs.

  11. MELT WIRE SENSORS AVAILABLE TO DETERMINE PEAK TEMPERATURES IN ATR IRRADIATION TESTING

    SciTech Connect

    K. L. Davis; D. Knudson; J. Daw; J. Palmer; J. L. Rempe

    2012-07-01

    In April 2007, the Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) to advance US leadership in nuclear science and technology. By attracting new users from universities, laboratories, and industry, the ATR will support basic and applied nuclear research and development and help address the nation's energy security needs. In support of this new program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. Although most efforts emphasize sensors capable of providing real-time data, selected tasks have been completed to enhance sensors provided in irradiation locations where instrumentation leads cannot be included, such as drop-in capsule and Hydraulic Shuttle Irradiation System (HSIS) or 'rabbit' locations. To meet the need for these locations, the INL has developed melt wire temperature sensors for use in ATR irradiation testing. Differential scanning calorimetry and environmental testing of prototypical sensors was used to develop a library of 28 melt wire materials, capable of detecting peak irradiation temperatures ranging from 85 to 1500°C. This paper will discuss the development work and present test results.

  12. Assessing and calibrating the ATR-FTIR approach as a carbonate rock characterization tool

    NASA Astrophysics Data System (ADS)

    Henry, Delano G.; Watson, Jonathan S.; John, Cédric M.

    2017-01-01

    ATR-FTIR (attenuated total reflectance Fourier transform infrared) spectroscopy can be used as a rapid and economical tool for qualitative identification of carbonates, calcium sulphates, oxides and silicates, as well as quantitatively estimating the concentration of minerals. Over 200 powdered samples with known concentrations of two, three, four and five phase mixtures were made, then a suite of calibration curves were derived that can be used to quantify the minerals. The calibration curves in this study have an R2 that range from 0.93-0.99, a RMSE (root mean square error) of 1-5 wt.% and a maximum error of 3-10 wt.%. The calibration curves were used on 35 geological samples that have previously been studied using XRD (X-ray diffraction). The identification of the minerals using ATR-FTIR is comparable with XRD and the quantitative results have a RMSD (root mean square deviation) of 14% and 12% for calcite and dolomite respectively when compared to XRD results. ATR-FTIR is a rapid technique (identification and quantification takes < 5 min) that involves virtually no cost if the machine is available. It is a common tool in most analytical laboratories, but it also has the potential to be deployed on a rig for real-time data acquisition of the mineralogy of cores and rock chips at the surface as there is no need for special sample preparation, rapid data collection and easy analysis.

  13. Cyclohexene Photo-oxidation over Vanadia Catalyst Analyzed by Time Resolved ATR-FT-IR Spectroscopy

    SciTech Connect

    Frei, Heinz; Mul, Guido; Wasylenko, Walter; Hamdy, M. Sameh; Frei, Heinz

    2008-06-04

    Vanadia was incorporated in the 3-dimensional mesoporous material TUD-1 with a loading of 2percent w/w vanadia. The performance in the selective photo-oxidation of liquid cyclohexene was investigated using ATR-FT-IR spectroscopy. Under continuous illumination at 458 nm a significant amount of product, i.e. cyclohexenone, was identified. This demonstrates for the first time that hydroxylated vanadia centers in mesoporous materials can be activated by visible light to induce oxidation reactions. Using the rapid scan method, a strong perturbation of the vanadyl environment could be observed in the selective oxidation process induced by a 458 nm laser pulse of 480 ms duration. This is proposed to be caused by interaction of the catalytic centre with a cyclohexenyl hydroperoxide intermediate. The restoration of the vanadyl environment could be kinetically correlated to the rate of formation of cyclohexenone, and is explained by molecular rearrangement and dissociation of the peroxide to ketone and water. The ketone diffuses away from the active center and ATR infrared probing zone, resulting in a decreasing ketone signal on the tens of seconds time scale after initiation of the photoreaction. This study demonstrates the high potential of time resolved ATR FT-IR spectroscopy for mechanistic studies of liquid phase reactions by monitoring not only intermediates and products, but by correlating the temporal behavior of these species to molecular changes of the vanadyl catalytic site.

  14. Measuring photochemical kinetics in submonolayer films by transient ATR spectroscopy on a multimode planar waveguide.

    PubMed

    Simon, Anne M; Marucci, Nicole E; Saavedra, S Scott

    2011-07-15

    Understanding the kinetics of reactions in molecular thin films can aid in the molecular engineering of organic photovoltaics and biosensors. We have coupled two analytical methods, transient absorbance spectroscopy (TAS) and attenuated total reflectance (ATR), in a relatively simple arrangement when compared with previous TAS/ATR instruments to interrogate molecular structure and photochemistry at interfaces. The multimode planar waveguide geometry provides a significant path length enhancement relative to a conventional transmission geometry, making it feasible to perform measurements on low-surface-coverage films. The performance of the instrument was assessed using a thin film composed of purple membrane (PM) fragments containing bacteriorhodopsin deposited onto PDAC, a positively charged polymer. The surface coverage of retinal chromophore in this film is ∼0.1 monolayer and its orientation distribution is anisotropic, with a mean tilt angle of 68° from surface normal. After photoinduced formation of the transient M state, the chromophore decays to the ground state in 4.4 ± 0.6 ms, equivalent to the decay of suspended PM fragments, which shows that deposition on PDAC does not alter M-state photokinetics. The surface coverage of the M state is calculated to be 2 pmol/cm(2), which is ∼1% of a close-packed monolayer. This work demonstrates that TAS/ATR can be used to probe structure and photochemical kinetics in molecular films at extremely low surface coverages.

  15. A theoretical framework for 3D LADAR ATR problem definition and performance evaluation

    NASA Astrophysics Data System (ADS)

    DelMarco, Stephen; Sobel, Erik; Douglas, Joel

    2005-05-01

    LADAR imagery provides the capability to represent high resolution detail of 3D surface geometry of complex targets. In previous work we exploited this capability for automatic target recognition (ATR) by developing matching algorithms for performing surface matching of 3D LADAR point clouds with highly-detailed target CAD models. A central challenge in evaluating ATR performance is characterizing the degree of problem difficulty. One of the most important factors is the inherent similarity of target signatures. We've developed a flexible approach to target taxonomy based on 3D shape which includes a classification framework for defining the target recognition problem and evaluating ATR algorithm performance. The target model taxonomy consists of a hierarchical, tree-structured target classification scheme in which different levels of the tree correspond to different degrees of target classification difficulty. Each node in the tree corresponds to a collection of target models forming a target category. Target categories near the tree root represent large and very general target classes, exhibiting large interclass distance. Targets in these categories are easily separated. Target categories near the tree bottom represent very specific target classes with small interclass distance. These targets are difficult to separate. In this paper we focus on creation of optimal categories. We develop approaches for optimal aggregation of target model types into categories which provide for improved classification performance. We generate numerical results using match scores derived from matching highly-detailed CAD models of civilian ground vehicles.

  16. Pressure-modulation dynamic attenuated-total-reflectance (ATR) FT-IR spectroscopy

    NASA Astrophysics Data System (ADS)

    Marcott, C.; Story, G. M.; Noda, I.; Bibby, A.; Manning, C. J.

    1998-06-01

    A single-reflectance attenuated-total-reflectance (ATR) accessory with a diamond internal-reflection element was modified by the addition of a piezoelectric transducer. Initial dynamic pressure-modulation experiments have been performed in the sample compartment of a step-scanning FT-IR spectrometer. A sinusoidal pressure modulation applied to samples of isotactic polypropylene and linear low density polyethylene resulted in dynamic responses which appear to be similar to those observed in previous dynamic 2D IR experiments. Preliminary pressure-modulation dynamic ATR results are also reported for a styrene-butadiene-styrene triblock copolymer. The new method has the advantages that a much wider variety of sample types and geometries can be studied and less sample preparation is required. Dynamic 2D IR experiments carried out by ATR no longer require thin films of large area and sufficient strength to withstand the dynamic strain applied by a rheometer. The ability to obtain dynamic IR spectroscopic information from a wider variety of sample types and thicknesses would greatly expand the amount of useful information that could be extracted from normally complicated, highly overlapped IR spectra.

  17. Visible attenuated total reflection (ATR): a new technique for high-strength pigment analyses.

    PubMed

    Lee, Kathryn A; Rich, Danny C

    2011-03-01

    A visible-attenuated total reflection (visible-ATR) device was designed to provide a method for directly determining the relative tint strength in high-strength inks. This device showed good reproducibility and the spectra could be correlated to known values of relative tint strength in viscous, highly pigmented inks well within the industry-acceptable error (±5% tint strength). The results of the visible-ATR measurements were compared to those from mid-infrared (mid-IR) and near-infrared (NIR) spectroscopy and the capabilities of those techniques for determining ink strength. Mid-IR analysis was able to directly quantify relative tint strengths, as well as correlating to known values, and to qualify ink products by spectral matching. NIR analysis was able to quantify the tint strength based on the vehicle concentrations in the NIR region. The visible region of the NIR spectrometer was not able to be used for quantification. The vis-ATR and mid-IR spectra showed changes over the time scale of minutes, indicating self-stratification of the pigment and varnish.

  18. [Spectral analysis of ball pen script by FTIR microscope with ATR objective].

    PubMed

    Huang, Tao-Hong; Wu, Tian-Ming

    2007-11-01

    Inspection of ball pen script is very important in public security and justice field. It is difficult to get a good spectrum directly by infrared microscope reflectance mode because of low reflectivity of paper and dark gray in color. The best way to measure low reflectivity sample is by infrared microscope with ATR objective method. Measurement with the microscopic ATR method involves bringing the trace of ball pen ink into contact with the prism. By this method, some mixed spectra of ball pen ink and paper fiber were obtained from one of the actual sample. The spectrum of the paper was subtracted from those mixed spectra and a pure spectrum of the ball pen ink was obtained. In this spectrum, three strong peaks were found 1 581, 1 361 and 1 172 cm(-1) respectively, all from crystal violet, a typical triphenylmethane pigment. Another strong peak at 1 724 cm(-1) is contributed by carbonyl vibration from oil reagent alkyd. A 3D graph, showing the distribution of peak 1 581 cm(-1) in this area, was set up by using mapping software. In the 3D distribution graph, the figure of ball pen trace vividly appeared. This infrared microscope ATR method makes it available to nondestructively inspect original ball pen script.

  19. Stepwise Activation of the ATR Signaling Pathway upon Increasing Replication Stress Impacts Fragile Site Integrity

    PubMed Central

    Koundrioukoff, Stéphane; Carignon, Sandra; Técher, Hervé; Letessier, Anne; Brison, Olivier; Debatisse, Michelle

    2013-01-01

    Breaks at common fragile sites (CFS) are a recognized source of genome instability in pre-neoplastic lesions, but how such checkpoint-proficient cells escape surveillance and continue cycling is unknown. Here we show, in lymphocytes and fibroblasts, that moderate replication stresses like those inducing breaks at CFSs trigger chromatin loading of sensors and mediators of the ATR pathway but fail to activate Chk1 or p53. Consistently, we found that cells depleted of ATR, but not of Chk1, accumulate single-stranded DNA upon Mre11-dependent resection of collapsed forks. Partial activation of the pathway under moderate stress thus takes steps against fork disassembly but tolerates S-phase progression and mitotic onset. We show that fork protection by ATR is crucial to CFS integrity, specifically in the cell type where a given site displays paucity in backup replication origins. Tolerance to mitotic entry with under-replicated CFSs therefore results in chromosome breaks, providing a pool of cells committed to further instability. PMID:23874235

  20. The detection and discrimination of human body fluids using ATR FT-IR spectroscopy.

    PubMed

    Orphanou, Charlotte-Maria; Walton-Williams, Laura; Mountain, Harry; Cassella, John

    2015-07-01

    Blood, saliva, semen and vaginal secretions are the main human body fluids encountered at crime scenes. Currently presumptive tests are routinely utilised to indicate the presence of body fluids, although these are often subject to false positives and limited to particular body fluids. Over the last decade more sensitive and specific body fluid identification methods have been explored, such as mRNA analysis and proteomics, although these are not yet appropriate for routine application. This research investigated the application of ATR FT-IR spectroscopy for the detection and discrimination of human blood, saliva, semen and vaginal secretions. The results demonstrated that ATR FT-IR spectroscopy can detect and distinguish between these body fluids based on the unique spectral pattern, combination of peaks and peak frequencies corresponding to the macromolecule groups common within biological material. Comparisons with known abundant proteins relevant to each body fluid were also analysed to enable specific peaks to be attributed to the relevant protein components, which further reinforced the discrimination and identification of each body fluid. Overall, this preliminary research has demonstrated the potential for ATR FT-IR spectroscopy to be utilised in the routine confirmatory screening of biological evidence due to its quick and robust application within forensic science. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Identification of species' blood by attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopy.

    PubMed

    Mistek, Ewelina; Lednev, Igor K

    2015-09-01

    Blood is one of the most common and informative forms of biological evidence found at a crime scene. A very crucial step in forensic investigations is identifying a blood stain's origin. The standard methods currently employed for analyzing blood are destructive to the sample and time-consuming. In this study, attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopy is used as a confirmatory, nondestructive, and rapid method for distinction between human and animal (nonhuman) blood. Partial least squares-discriminant analysis (PLS-DA) models were built and demonstrated complete separation between human and animal donors, as well as distinction between three separate species: human, cat, and dog. Classification predictions of unknown blood donors were performed by the model, resulting in 100 % accuracy. This study demonstrates ATR FT-IR spectroscopy's great potential for blood stain analysis and species discrimination, both in the lab and at a crime scene since portable ATR FT-IR instrumentation is commercially available.

  2. ATR-IR Investigation of Solvent Interactions with Surface-Bound Polymers

    PubMed Central

    2016-01-01

    Solvent interactions with bulk and surface-bound polymer brushes are crucial for functionalities such as controlled friction and thermoresponsive adhesion. To study such interactions, the temperature-induced solvent-quality changes and the effect of surface tethering on the mechanical and tribological properties of poly(dodecyl methacrylate) (P12MA) brushes have been investigated by means of attenuated total reflection infrared spectroscopy (ATR-IR), as well as atomic force microscopy (AFM) and lateral force microscopy (LFM). These results have been compared with temperature-dependent UV–visible spectrophotometry (UV–vis) data for the corresponding bulk polymer solutions. The ATR-IR results clearly show that increasing temperature enhances ethanol uptake in P12MA, which results in film swelling. This is accompanied by a marked increase in both adhesion and friction. We have also shown that a combination of solvents, such as toluene and ethanol, can lead to a temperature-dependent solvent partitioning within the polymer brush. To our knowledge this is the first time preferential solvent uptake in a grafted-from brush has been monitored via in situ ATR-IR. Moreover, we have observed remarkably different behavior for polymer chains in solution compared to the behavior of similar chains bound to a surface. The presented findings on the temperature-dependent solvent interactions of surface-grafted P12MA reveal previously unknown solvation phenomena and open up a range of possible applications in the area of stimuli-responsive materials. PMID:27397856

  3. The MRE11 GAR motif regulates DNA double-strand break processing and ATR activation

    PubMed Central

    Yu, Zhenbao; Vogel, Gillian; Coulombe, Yan; Dubeau, Danielle; Spehalski, Elizabeth; Hébert, Josée; Ferguson, David O; Masson, Jean Yves; Richard, Stéphane

    2012-01-01

    The MRE11/RAD50/NBS1 complex is the primary sensor rapidly recruited to DNA double-strand breaks (DSBs). MRE11 is known to be arginine methylated by PRMT1 within its glycine-arginine-rich (GAR) motif. In this study, we report a mouse knock-in allele of Mre11 that substitutes the arginines with lysines in the GAR motif and generates the MRE11RK protein devoid of methylated arginines. The Mre11RK/RK mice were hypersensitive to γ-irradiation (IR) and the cells from these mice displayed cell cycle checkpoint defects and chromosome instability. Moreover, the Mre11RK/RK MEFs exhibited ATR/CHK1 signaling defects and impairment in the recruitment of RPA and RAD51 to the damaged sites. The MRKRN complex formed and localized to the sites of DNA damage and normally activated the ATM pathway in response to IR. The MRKRN complex exhibited exonuclease and DNA-binding defects in vitro responsible for the impaired DNA end resection and ATR activation observed in vivo in response to IR. Our findings provide genetic evidence for the critical role of the MRE11 GAR motif in DSB repair, and demonstrate a mechanistic link between post-translational modifications at the MRE11 GAR motif and DSB processing, as well as the ATR/CHK1 checkpoint signaling. PMID:21826105

  4. Inherited germline ATRX mutation in two brothers with ATR-X syndrome and osteosarcoma.

    PubMed

    Ji, Jianling; Quindipan, Catherine; Parham, David; Shen, Lishuang; Ruble, David; Bootwalla, Moiz; Maglinte, Dennis T; Gai, Xiaowu; Saitta, Sulagna C; Biegel, Jaclyn A; Mascarenhas, Leo

    2017-05-01

    We report a family in which two brothers had an undiagnosed genetic disorder comprised of dysmorphic features, microcephaly, severe intellectual disability (non-verbal), mild anemia, and cryptorchidism. Both developed osteosarcoma. Trio exome sequencing (using blood samples from the younger brother and both parents) was performed and a nonsense NM_000489.4:c.7156C>T (p.Arg2386*) mutation in the ATRX gene was identified in the proband (hemizygous) and in the mother's peripheral blood DNA (heterozygous). The mother is healthy, does not exhibit any clinical manifestations of ATR-X syndrome and there was no family history of cancer. The same hemizygous pathogenic variant was confirmed in the affected older brother's skin tissue by subsequent Sanger sequencing. Chromosomal microarray studies of both brothers' osteosarcomas revealed complex copy number alterations consistent with the clinical diagnosis of osteosarcoma. Recently, somatic mutations in the ATRX gene have been observed as recurrent alterations in both osteosarcoma and brain tumors. However, it is unclear if there is any association between osteosarcoma and germline ATRX mutations, specifically in patients with constitutional ATR-X syndrome. This is the first report of osteosarcoma diagnosed in two males with ATR-X syndrome, suggesting a potential increased risk for cancer in patients with this disorder. © 2017 Wiley Periodicals, Inc.

  5. FTIR-ATR spectroscopy applied to quality control of grape-derived spirits.

    PubMed

    Anjos, Ofélia; Santos, António J A; Estevinho, Letícia M; Caldeira, Ilda

    2016-08-15

    The Fourier transform infrared (FTIR) spectroscopic method with attenuated total reflectance (ATR) was used for predicting the alcoholic strength, the methanol, acetaldehyde and fusel alcohols content of grape-derived spirits. FTIR-ATR spectrum in the mid-IR region (4000-400 cm(-1)) was used for the quantitative estimation by applying partial least square (PLS) regression models and the results were correlated with those obtained from reference methods. In the developed method, a cross-validation with 50% of the samples was used for PLS analysis along with a validation test set with 50% of the remaining samples. Good correlation models with a great accuracy were obtained for methanol (r(2)=99.4; RPD=12.8), alcoholic strength (r(2)=97.2; RPD=6.0), acetaldehyde (r(2)=98.2; RPD=7.5) and fusel alcohols (r(2) from 97.4 to 94.1; RPD from 6.2 to 4.1). These results corroborate the hypothesis that FTIR-ATR is a useful technique for the quality control of grape-derived spirits, whose practical application may improve the efficiency and quickness of the current laboratory analysis.

  6. AGR-2 Data Qualification Report for ATR Cycles 149B, 150A, 150B, 151A, and 151B

    SciTech Connect

    Michael L. Abbott; Binh T. Pham

    2012-06-01

    This report provides the data qualification status of AGR-2 fuel irradiation experimental data from Advanced Test Reactor (ATR) cycles 149B, 150A, 150B, 151A, and 151B), as recorded in the Nuclear Data Management and Analysis System (NDMAS). The AGR-2 data streams addressed include thermocouple temperatures, sweep gas data (flow rate, pressure, and moisture content), and fission product monitoring system (FPMS) data for each of the six capsules in the experiment. A total of 3,307,500 5-minute thermocouple and sweep gas data records were received and processed by NDMAS for this period. There are no AGR-2 data for cycle 150A because the experiment was removed from the reactor. Of these data, 82.2% were determined to be Qualified based on NDMAS accuracy testing and data validity assessment. There were 450,557 Failed temperature records due to thermocouple failures, and 138,528 Failed gas flow records due to gas flow cross-talk and leakage problems that occurred in the capsules after cycle 150A. For FPMS data, NDMAS received and processed preliminary release rate and release-to-birth rate ratio (R/B) data for the first three reactor cycles (cycles 149B, 150B, and 151B). This data consists of 45,983 release rate records and 45,235 R/B records for the 12 radionuclides reported. The qualification status of these FPMS data has been set to In Process until receipt of QA-approved data generator reports. All of the above data have been processed and tested using a SAS®-based enterprise application software system, stored in a secure Structured Query Language database, and made available on the NDMAS Web portal (http://ndmas.inl.gov) for both internal and external VHTR project participants.

  7. The ATM- and ATR-related SCD domain is over-represented in proteins involved in nervous system development

    PubMed Central

    Cara, Lukas; Baitemirova, Medina; Follis, Jack; Larios-Sanz, Maia; Ribes-Zamora, Albert

    2016-01-01

    ATM and ATR are cellular kinases with a well-characterized role in the DNA-damage response. Although the complete set of ATM/ATR targets is unknown, they often contain clusters of S/TQ motifs that constitute an SCD domain. In this study, we identified putative ATM/ATR targets that have a conserved SCD domain across vertebrates. Using this approach, we have identified novel putative ATM/ATR targets in pathways known to be under direct control of these kinases. Our analysis has also unveiled significant enrichment of SCD-containing proteins in cellular pathways, such as vesicle trafficking and actin cytoskeleton, where a regulating role for ATM/ATR is either unknown or poorly understood, hinting at a much broader and overarching role for these kinases in the cell. Of particular note is the overrepresentation of conserved SCD-containing proteins involved in pathways related to neural development. This finding suggests that ATM/ATR could be directly involved in controlling this process, which may be linked to the adverse neurological effects observed in patients with mutations in ATM. PMID:26743489

  8. RPA70 depletion induces hSSB1/2-INTS3 complex to initiate ATR signaling

    PubMed Central

    Kar, Ananya; Kaur, Manpreet; Ghosh, Tanushree; Khan, Md. Muntaz; Sharma, Aparna; Shekhar, Ritu; Varshney, Akhil; Saxena, Sandeep

    2015-01-01

    The primary eukaryotic single-stranded DNA-binding protein, Replication protein A (RPA), binds to single-stranded DNA at the sites of DNA damage and recruits the apical checkpoint kinase, ATR via its partner protein, ATRIP. It has been demonstrated that absence of RPA incapacitates the ATR-mediated checkpoint response. We report that in the absence of RPA, human single-stranded DNA-binding protein 1 (hSSB1) and its partner protein INTS3 form sub-nuclear foci, associate with the ATR-ATRIP complex and recruit it to the sites of genomic stress. The ATRIP foci formed after RPA depletion are abrogated in the absence of INTS3, establishing that hSSB-INTS3 complex recruits the ATR-ATRIP checkpoint complex to the sites of genomic stress. Depletion of homologs hSSB1/2 and INTS3 in RPA-deficient cells attenuates Chk1 phosphorylation, indicating that the cells are debilitated in responding to stress. We have identified that TopBP1 and the Rad9-Rad1-Hus1 complex are essential for the alternate mode of ATR activation. In summation, we report that the single-stranded DNA-binding protein complex, hSSB1/2-INTS3 can recruit the checkpoint complex to initiate ATR signaling. PMID:25916848

  9. Small Molecule Inhibition of p38 MAP Kinase Extends the Replicative Life Span of Human ATR-Seckel Syndrome Fibroblasts

    PubMed Central

    2013-01-01

    Ataxia-telangiectasia and rad3 (ATR)-related Seckel syndrome is associated with growth retardation and premature aging features. ATR-Seckel fibroblasts have a reduced replicative capacity in vitro and an aged morphology that is associated with activation of stress-associated p38 mitogen-activated protein kinase and phosphorylated HSP27. These phenotypes are prevented using p38 inhibitors, with replicative capacity restored to the normal range. However, this stressed phenotype is retained in telomerase-immortalized ATR-Seckel fibroblasts, indicating that it is independent of telomere erosion. As with normal fibroblasts, senescence in ATR-Seckel is bypassed by p53 abrogation. Young ATR-Seckel fibroblasts show elevated levels of p21WAF1, p16INK4A, phosphorylated actin-binding protein cofilin, and phosphorylated caveolin-1, with small molecule drug inhibition of p38 reducing p16INK4A and caveolin-1 phosphorylation. In conclusion, ATR-Seckel fibroblasts undergo accelerated aging via stress-induced premature senescence and p38 activation that may underlie certain clinical features of Seckel syndrome, and our data suggest a novel target for pharmacological intervention in this human syndrome. PMID:23401567

  10. ATR-dependent phosphorylation of FANCA on serine 1449 after DNA damage is important for FA pathway function

    PubMed Central

    Collins, Natalie B.; Wilson, James B.; Bush, Thomas; Thomashevski, Andrei; Roberts, Kate J.; Jones, Nigel J.

    2009-01-01

    Previous work has shown several proteins defective in Fanconi anemia (FA) are phosphorylated in a functionally critical manner. FANCA is phosphorylated after DNA damage and localized to chromatin, but the site and significance of this phosphorylation are unknown. Mass spectrometry of FANCA revealed one phosphopeptide, phosphorylated on serine 1449. Serine 1449 phosphorylation was induced after DNA damage but not during S phase, in contrast to other posttranslational modifications of FA proteins. Furthermore, the S1449A mutant failed to completely correct a variety of FA-associated phenotypes. The DNA damage response is coordinated by phosphorylation events initiated by apical kinases ATM (ataxia telangectasia mutated) and ATR (ATM and Rad3-related), and ATR is essential for proper FA pathway function. Serine 1449 is in a consensus ATM/ATR site, phosphorylation in vivo is dependent on ATR, and ATR phosphorylated FANCA on serine 1449 in vitro. Phosphorylation of FANCA on serine 1449 is a DNA damage–specific event that is downstream of ATR and is functionally important in the FA pathway. PMID:19109555

  11. The ATM- and ATR-related SCD domain is over-represented in proteins involved in nervous system development.

    PubMed

    Cara, Lukas; Baitemirova, Medina; Follis, Jack; Larios-Sanz, Maia; Ribes-Zamora, Albert

    2016-01-08

    ATM and ATR are cellular kinases with a well-characterized role in the DNA-damage response. Although the complete set of ATM/ATR targets is unknown, they often contain clusters of S/TQ motifs that constitute an SCD domain. In this study, we identified putative ATM/ATR targets that have a conserved SCD domain across vertebrates. Using this approach, we have identified novel putative ATM/ATR targets in pathways known to be under direct control of these kinases. Our analysis has also unveiled significant enrichment of SCD-containing proteins in cellular pathways, such as vesicle trafficking and actin cytoskeleton, where a regulating role for ATM/ATR is either unknown or poorly understood, hinting at a much broader and overarching role for these kinases in the cell. Of particular note is the overrepresentation of conserved SCD-containing proteins involved in pathways related to neural development. This finding suggests that ATM/ATR could be directly involved in controlling this process, which may be linked to the adverse neurological effects observed in patients with mutations in ATM.

  12. Mechanisms responsible for the synergistic antileukemic interactions between ATR inhibition and cytarabine in acute myeloid leukemia cells

    PubMed Central

    Ma, Jun; Li, Xinyu; Su, Yongwei; Zhao, Jianyun; Luedtke, Daniel A.; Epshteyn, Valeria; Edwards, Holly; Wang, Guan; Wang, Zhihong; Chu, Roland; Taub, Jeffrey W.; Lin, Hai; Wang, Yue; Ge, Yubin

    2017-01-01

    Acute myeloid leukemia (AML) continues to be a challenging disease to treat, thus new treatment strategies are needed. In this study, we investigated the antileukemic effects of ATR inhibition alone or combined with cytarabine in AML cells. Treatment with the ATR-selective inhibitor AZ20 caused proliferation inhibition in AML cell lines and primary patient samples. It partially abolished the G2 cell cycle checkpoint and caused DNA replication stress and damage, accompanied by CDK1-independent apoptosis and downregulation of RRM1 and RRM2. AZ20 synergistically enhanced cytarabine-induced proliferation inhibition and apoptosis, abolished cytarabine-induced S and G2/M cell cycle arrest, and cooperated with cytarabine in inducing DNA replication stress and damage in AML cell lines. These key findings were confirmed with another ATR-selective inhibitor AZD6738. Therefore, the cooperative induction of DNA replication stress and damage by ATR inhibition and cytarabine, and the ability of ATR inhibition to abrogate the G2 cell cycle checkpoint both contributed to the synergistic induction of apoptosis and proliferation inhibition in AML cell lines. Synergistic antileukemic interactions between AZ20 and cytarabine were confirmed in primary AML patient samples. Our findings provide insight into the mechanism of action underlying the synergistic antileukemic activity of ATR inhibition in combination with cytarabine in AML. PMID:28176818

  13. A method for checking homogeneity of subsurface regions by variable angle ATR: Experiments on polymers vs. optical modelling

    NASA Astrophysics Data System (ADS)

    Hopfe, I.; Eichhorn, K.-J.; Hopfe, V.; Grählert, W.

    1998-06-01

    The subsurface structure of many technically applied materials is characterized by alterations of the composition (swelling or surface reactions on polymers, leaching of glasses etc.). Attenuated total reflection (ATR) spectroscopy is a powerful tool for analyzing such surface regions. Because of problems with optical contact the ATR method is difficult to handle in practice. Based on variable angle ATR-FTIR spectroscopy a straightforward method has been established which can detect compositional inhomogeneities in subsurface regions or across layers. The method works as follows: (i) making ATR measurements at two different angles of incidence without changing the sample, (ii) normalizing the ATR absorbance spectra by using an appropriate band of the substrate as an internal standard, (iii) calculating difference spectra of the normalized spectra. In the case of a homogeneous material the difference spectrum virtually vanishes whereas in the case of an inhomogeneous surface region the difference spectrum reflects the compositional gradient. The method has been tested at polyamide-12 foils: (a) chemically cleaned, (b) treated with initiator, and (c) treated with pluronic. The experimental findings have been supported by spectra modelling. Based on an optical multilayer model the ATR spectra of a homogeneous polymer and of the same material with a slightly altered surface layer have been calculated for different angles of incidence. By applying steps (ii) to (iii) the experimental results are confirmed.

  14. Small Molecules Targeting Ataxia Telangiectasia and Rad3-Related (ATR) Kinase: An Emerging way to Enhance Existing Cancer Therapy.

    PubMed

    Andrs, Martin; Korabecny, Jan; Nepovimova, Eugenie; Jun, Daniel; Hodny, Zdenek; Kuca, Kamil

    2016-01-01

    The main aim of current cancer research is to find a way to selectively affect the tumor cells, while leaving normal cells intact. Ataxia telangiectasia and Rad3-related kinase (ATR), a member of the phosphatidylinositol-3-related protein kinases (PIKK), represents a candidate target for achieving this goal. ATR kinase is one of the main kinases of the DNA damage response signaling pathway and responds to DNA damage caused by replication stress and various genotoxic agents (i.e. chemotherapy, ionizing radiation, ultraviolet light). ATR activation triggers cell cycle checkpoints, DNA repair and apoptosis, but also resistance of tumor cells to DNA damaging agents, through stress support under replication stress. Thus, the inhibition of ATR leads to increased effectiveness of cancer therapy and in addition enables highly selective targeting of cancer cells through synthetic lethal interactions. Despite this great potential, only a few potent and selective inhibitors of ATR kinase have been developed to date. However, those which have been developed provide great promise, and are under evaluation in many current preclinical and clinical trials. The purpose of this review is to summarize the potential of ATR inhibitors and the medicinal chemistry efforts which resulted in their identification.

  15. INITIAL IRRADIATION OF THE FIRST ADVANCED GAS REACTOR FUEL DEVELOPMENT AND QUALIFICATION EXPERIMENT IN THE ADVANCED TEST REACTOR

    SciTech Connect

    S. Blaine Grover; David A. Petti

    2007-09-01

    The United States Department of Energy’s Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating eight separate tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States. The ATR has a long history of irradiation testing in support of reactor development and the INL has been designated as the United States Department of Energy’s lead laboratory for nuclear energy development. The ATR is one of the world’s premiere test reactors for performing long term, high flux, and/or large volume irradiation test programs. These AGR fuel experiments will be irradiated over the next ten years to demonstrate and qualify new particle fuel for use in high temperature gas reactors. The experiments, which will each consist of six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control for each capsule. The swept gas will also have on-line fission product monitoring to track performance of the fuel in each individual capsule during irradiation.

  16. Modeling of MOX Fuel Pellet-Clad Interaction Using ABAQUS

    SciTech Connect

    Ambrosek, Richard G.; Pedersen, Robert C.; Maple, Amanda

    2002-07-01

    Post-irradiation examination (PIE) has indicated an increase in the outer diameter of fuel pins being irradiated in the Advanced Test Reactor (ATR) for the MOX irradiation program. The diameter increase is the largest in the region between fuel pellets. The fuel pellet was modeled using PATRAN and the model was evaluated using ABAQUS, version 6.2. The results from the analysis indicate the non-uniform clad diameter is caused by interaction between the fuel pellet and the clad. The results also demonstrate that the interaction is not uniform over the pellet axial length, with the largest interaction occurring in the region of the pellet-pellet interface. Results were obtained for an axisymmetric model and for a 1/8 pie shaped segment, using the coupled temperature-displacement solution technique. (authors)

  17. Operando fuel cell spectroscopy

    NASA Astrophysics Data System (ADS)

    Kendrick, Ian Michael

    The active state of a catalyst only exists during catalysis (1) provided the motivation for developing operando spectroscopic techniques. A polymer electrolyte membrane fuel cell (PEMFC) was designed to interface with commercially available instruments for acquisition of infrared spectra of the catalytic surface of the membrane electrode assembly (MEA) during normal operation. This technique has provided insight of the complex processes occurring at the electrode surface. Nafion, the solid electrolyte used in most modern-day polymer electrolyte membrane fuel cells (PEMFC), serves many purposes in fuel cell operation. However, there is little known of the interface between Nafion and the electrode surface. Previous studies of complex Stark tuning curves of carbon monoxide on the surface of a platinum electrode were attributed the co-adsorption of bisulfite ions originating from the 0.5M H2SO4 electrolyte used in the study(2). Similar tuning curves obtained on a fuel cell MEA despite the absence of supplemental electrolytes suggest the adsorption of Nafion onto platinum (3). The correlation of spectra obtained using attenuated total reflectance spectroscopy (ATR) and polarization modulated IR reflection-absorption spectroscopy (PM-IRRAS) to a theoretical spectrum generated using density functional theory (DFT) lead to development of a model of Nafion and platinum interaction which identified participation of the SO3- and CF3 groups in Nafion adsorption. The use of ethanol as a fuel stream in proton exchange membrane fuel cells provides a promising alternative to methanol. Relative to methanol, ethanol has a greater energy density, lower toxicity and can be made from the fermentation of biomass(4). Operando IR spectroscopy was used to study the oxidation pathway of ethanol and Stark tuning behavior of carbon monoxide on Pt, Ru, and PtRu electrodes. Potential dependent products such as acetaldehyde, acetic acid and carbon monoxide are identified as well as previously

  18. Synthetic Fuel

    SciTech Connect

    Idaho National Laboratory - Steve Herring, Jim O'Brien, Carl Stoots

    2008-03-26

    Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhouse gass Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhous

  19. Synthetic Fuel

    ScienceCinema

    Idaho National Laboratory - Steve Herring, Jim O'Brien, Carl Stoots

    2016-07-12

    Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhouse gass Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhous

  20. Fuel cells

    NASA Astrophysics Data System (ADS)

    1984-12-01

    The US Department of Energy (DOE), Office of Fossil Energy, has supported and managed a fuel cell research and development (R and D) program since 1976. Responsibility for implementing DOE's fuel cell program, which includes activities related to both fuel cells and fuel cell systems, has been assigned to the Morgantown Energy Technology Center (METC) in Morgantown, West Virginia. The total United States effort of the private and public sectors in developing fuel cell technology is referred to as the National Fuel Cell Program (NFCP). The goal of the NFCP is to develop fuel cell power plants for base-load and dispersed electric utility systems, industrial cogeneration, and on-site applications. To achieve this goal, the fuel cell developers, electric and gas utilities, research institutes, and Government agencies are working together. Four organized groups are coordinating the diversified activities of the NFCP. The status of the overall program is reviewed in detail.

  1. Future Fuels

    DTIC Science & Technology

    2005-10-04

    tactical ground mobility and increasing operational reach • Identify, review, and assess – Technologies for reducing fuel consumption, including...T I O N S A C T I O N S TOR Focus - Tactical ground mobility - Operational reach - Not A/C, Ships, or troops Hybrid Electric Vehicle Fuel Management...Fuel Management During Combat Operations Energy Fundamentals • Energy Density • Tactical Mobility • Petroleum Use • Fuel Usage (TWV) • TWV OP TEMPO TOR

  2. Alternative Fuels

    DTIC Science & Technology

    2009-06-11

    JP-8 BACK-UP SLIDES Unclassified 19 What Are Biofuels ? Cellulose “first generation”“second generation” C18:0 C16:1 Triglycerides (fats, oils ...equipment when supplying jet fuel not practicable or cost effective Unclassified 5 erna ve ue s ocus Petroleum Crude Oil (declining discovery / production...on Jet A/A-1 Approved fuels, DXXXX Unclassified 6 JP-8/5 (Commercial Jet Fuel, ASTM Spec) DARPA Alternative Jet Fuels • Agricultural crop oils

  3. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  4. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  5. Cultural conditions required for the induction of an adaptive acid-tolerance response (ATR) in Sinorhizobium meliloti and the question as to whether or not the ATR helps rhizobia improve their symbiosis with alfalfa at low pH.

    PubMed

    Draghi, Walter O; Del Papa, María Florencia; Pistorio, Mariano; Lozano, Mauricio; de Los Angeles Giusti, María; Torres Tejerizo, Gonzalo A; Jofré, Edgardo; Boiardi, José Luis; Lagares, Antonio

    2010-01-01

    Sinorhizobium meliloti associates with Medicago and Melilotus species to develop nitrogen-fixing symbioses. The agricultural relevance of these associations, the worldwide distribution of acid soils, and the remarkable acid sensitivity of the microsymbiont have all stimulated research on the responses of the symbionts to acid environments. We show here that an adaptive acid-tolerance response (ATR) can be induced in S. meliloti, as shown previously for Sinorhizobium medicae, when the bacteria are grown in batch cultures at the slightly acid pH of 6.1. In marked contrast, no increased tolerance to hydrogen ions is obtained if rhizobia are grown in a chemostat under continuous cultivation at the same pH. The adaptive ATR appears as a complex process triggered by an increased hydrogen-ion concentration, but operative only if other--as yet unknown--concomitant factors that depend on the culture conditions are present (although not provided under continuous cultivation). Although the stability of the ATR and its influence on acid tolerance has been characterized in rhizobia, no data have been available on the effect of the adapted state on symbiosis. Coinoculation experiments showed that acid-adapted indicator rhizobia (ATR+) were present in >90% of the nodules when nodulation was performed at pH 5.6, representing a >30% increase in occupancy compared with a control test. We show that the ATR represents a clear advantage in competing for nodulation at low pH. It is not yet clear whether such an effect results from an improved performance in the acid environment during preinfection, an enhanced ability to initiate infections, or both conditions. The practical use of ATR+ rhizobia will depend on validation experiments with soil microcosms and on field testing, as well as on the possibility of preserving the physiology of ATR+ bacteria in inoculant formulations.

  6. Production of LEU Fully Ceramic Microencapsulated Fuel for Irradiation Testing

    SciTech Connect

    Terrani, Kurt A; Kiggans Jr, James O; McMurray, Jake W; Jolly, Brian C; Hunt, Rodney Dale; Trammell, Michael P; Snead, Lance Lewis

    2016-01-01

    Fully Ceramic Microencapsulated (FCM) fuel consists of tristructural isotropic (TRISO) fuel particles embedded inside a SiC matrix. This fuel inherently possesses multiple barriers to fission product release, namely the various coating layers in the TRISO fuel particle as well as the dense SiC matrix that hosts these particles. This coupled with the excellent oxidation resistance of the SiC matrix and the SiC coating layer in the TRISO particle designate this concept as an accident tolerant fuel (ATF). The FCM fuel takes advantage of uranium nitride kernels instead of oxide or oxide-carbide kernels used in high temperature gas reactors to enhance heavy metal loading in the highly moderated LWRs. Production of these kernels with appropriate density, coating layer development to produce UN TRISO particles, and consolidation of these particles inside a SiC matrix have been codified thanks to significant R&D supported by US DOE Fuel Cycle R&D program. Also, surrogate FCM pellets (pellets with zirconia instead of uranium-bearing kernels) have been neutron irradiated and the stability of the matrix and coating layer under LWR irradiation conditions have been established. Currently the focus is on production of LEU (7.3% U-235 enrichment) FCM pellets to be utilized for irradiation testing. The irradiation is planned at INL s Advanced Test Reactor (ATR). This is a critical step in development of this fuel concept to establish the ability of this fuel to retain fission products under prototypical irradiation conditions.

  7. Modelling an experimental methane fuel processor

    NASA Astrophysics Data System (ADS)

    Lin, Shi-Tin; Chen, Yih-Hang; Yu, Cheng-Ching; Liu, Yen-Chun; Lee, Chiou-Hwang

    Steady-state models are developed to describe an experimental methane fuel processor that is intended to provide hydrogen for a fuel cell system for power generation (2-3 kW). First-principle reactor models are constructed to describe a series of reactions, i.e., steam and autothermal reforming (SR/ATR), high- and low-temperature water-gas shift (HTS/LTS) reactions and preferential oxidation (PROX) reactions, at different sectors of the reactor system for methane reforming as well as gas cleaning. The pre-exponential factors of the rate constants are adjusted to fit the experimental data and the resultant reactor model provides a reasonably good description of steady-state behaviour. Next, sensitivity analyses are performed to locate the optimum operating point of the fuel processor. The objective function of the optimization is fuel processor efficiency. The dominating optimization variables include: the ratios of water and oxygen to the hydrocarbon feed to the autothermal reforming reactor and the inlet temperature of the reactor. The results indicate that further improvement in fuel processor efficiency can be made with a reliable process model.

  8. Alternative fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J. S.; Butze, H. F.; Friedman, R.; Antoine, A. C.; Reynolds, T. W.

    1977-01-01

    Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.

  9. Fuel compositions

    SciTech Connect

    Mekonen, K.

    1989-10-31

    This patent describes a hydrosol fuel. It comprises: from about 67% to 94% by weight of a hydrocarbon combustible fuel selected from the group consisting of the gasolines, diesel fuels and heavy fuel oils, from 5 to 25% by weight of water, at least one surfactant operable to create a hydrosol with the fuel and water present in the range of 0.1 up to about 3.4% by weight of an additive selected from the group consisting of alpha (mono) olefins and alkyl benzenes, each of the former having 7 to 15 recurring C{sub 2} monomers therein.

  10. Mutation in the 5' alternatively spliced region of the XNP/ATR-X gene causes Chudley-Lowry syndrome.

    PubMed

    Abidi, Fatima E; Cardoso, Carlos; Lossi, Anne-Marie; Lowry, Robert Brian; Depetris, Danielle; Mattéi, Marie-Geneviève; Lubs, Herbert A; Stevenson, Roger E; Fontes, Michel; Chudley, Albert E; Schwartz, Charles E

    2005-02-01

    The Chudley-Lowry syndrome (ChLS, MIM 309490) is an X-linked recessive condition characterized by moderate to severe mental retardation, short stature, mild obesity, hypogonadism, and distinctive facial features characterized by depressed nasal bridge, anteverted nares, inverted-V-shaped upper lip, and macrostomia. The original Chudley-Lowry family consists of three affected males in two generations. Linkage analysis had localized the gene to a large interval, Xp21-Xq26 and an obligate carrier was demonstrated to have highly skewed X inactivation. The combination of the clinical phenotype, consistent with that of the patients with ATR-X syndrome, the skewed X-inactivation pattern in a carrier female, as well as the mapping interval including band Xq13.3, prompted us to consider the XNP/ATR-X gene being involved in this syndrome. Using RT-PCR analysis, we screened the entire XNP/ATR-X gene and found a mutation in exon 2 (c.109C > T) giving rise to a stop codon at position 37 (p.R37X). Western blot and immunocytochemical analyses using a specific monoclonal antibody directed against XNP/ATR-X showed the protein to be present in lymphoblastoid cells from one affected male, despite the premature stop codon. To explain these discordant results, we further analyzed the 5' region of the XNP/ATR-X gene and found three alternative transcripts, which differ in the presence or absence of exon 2, and the length of exon 1. Our data suggest that ChLS is allelic to the ATR-X syndrome with its less severe phenotype being due to the presence of some XNP/ATR-X protein.

  11. Molecular cloning of AtRS4, a seed specific multifunctional RFO synthase/galactosylhydrolase in Arabidopsis thaliana

    PubMed Central

    Gangl, Roman; Behmüller, Robert; Tenhaken, Raimund

    2015-01-01

    Stachyose is among the raffinose family oligosaccharides (RFOs) one of the major water-soluble carbohydrates next to sucrose in seeds of a number of plant species. Especially in leguminous seeds, e.g. chickpea, stachyose is reported as the major component. In contrast to their ambiguous potential as essential source of carbon for germination, RFOs are indigestible for humans and can contribute to diverse abdominal disorders. In the genome of Arabidopsis thaliana, six putative raffinose synthase genes are reported, whereas little is known about these putative raffinose synthases and their biochemical characteristics or their contribution to the RFO physiology in A. thaliana. In this paper, we report on the molecular cloning, functional expression in Escherichia coli and purification of recombinant AtRS4 from A. thaliana and the biochemical characterisation of the putative stachyose synthase (AtSTS, At4g01970) as a raffinose and high affinity stachyose synthase (Km for raffinose 259.2 ± 21.15 μM) as well as stachyose and galactinol specific galactosylhydrolase. A T-DNA insertional mutant in the AtRS4 gene was isolated. Only semi-quantitative PCR from WT siliques showed a specific transcriptional AtRS4 PCR product. Metabolite measurements in seeds of ΔAtRS4 mutant plants revealed a total loss of stachyose in ΔAtRS4 mutant seeds. We conclude that AtRS4 is the only stachyose synthase in the genome of A. thaliana that AtRS4 represents a key regulation mechanism in the RFO physiology of A. thaliana due to its multifunctional enzyme activity and that AtRS4 is possibly the second seed specific raffinose synthase beside AtRS5, which is responsible for Raf accumulation under abiotic stress. PMID:26483807

  12. ATR- and ATM-Mediated DNA Damage Response Is Dependent on Excision Repair Assembly during G1 but Not in S Phase of Cell Cycle.

    PubMed

    Ray, Alo; Blevins, Chessica; Wani, Gulzar; Wani, Altaf A

    2016-01-01

    Cell cycle checkpoint is mediated by ATR and ATM kinases, as a prompt early response to a variety of DNA insults, and culminates in a highly orchestrated signal transduction cascade. Previously, we defined the regulatory role of nucleotide excision repair (NER) factors, DDB2 and XPC, in checkpoint and ATR/ATM-dependent repair pathway via ATR and ATM phosphorylation and recruitment to ultraviolet radiation (UVR)-induced damage sites. Here, we have dissected the molecular mechanisms of DDB2- and XPC- mediated regulation of ATR and ATM recruitment and activation upon UVR exposures. We show that the ATR and ATM activation and accumulation to UVR-induced damage not only depends on DDB2 and XPC, but also on the NER protein XPA, suggesting that the assembly of an active NER complex is essential for ATR and ATM recruitment. ATR and ATM localization and H2AX phosphorylation at the lesion sites occur as early as ten minutes in asynchronous as well as G1 arrested cells, showing that repair and checkpoint-mediated by ATR and ATM starts early upon UV irradiation. Moreover, our results demonstrated that ATR and ATM recruitment and H2AX phosphorylation are dependent on NER proteins in G1 phase, but not in S phase. We reasoned that in G1 the UVR-induced ssDNA gaps or processed ssDNA, and the bound NER complex promote ATR and ATM recruitment. In S phase, when the UV lesions result in stalled replication forks with long single-stranded DNA, ATR and ATM recruitment to these sites is regulated by different sets of proteins. Taken together, these results provide evidence that UVR-induced ATR and ATM recruitment and activation differ in G1 and S phases due to the existence of distinct types of DNA lesions, which promote assembly of different proteins involved in the process of DNA repair and checkpoint activation.

  13. TEM CHARACTERIZATION OF IRRADIATED U3SI2/AL DISPERSION FUEL

    SciTech Connect

    J. Gan; B. Miller; D. Keiser; A. Robinson; P. Medvedev; D. Wachs

    2010-10-01

    The silicide dispersion fuel of U3Si2/Al has been recognized as a reasonably good performance fuel for nuclear research and test reactors except that it requires the use of high enrichment uranium. An irradiated U3Si2/Al dispersion fuel (~75% enrichment) from the high flux side of a RERTR-8 (U0R040) plate was characterized using transmission electron microscopy (TEM). The fuel plate was irradiated in the advanced test reactor (ATR) for 105 days. The average irradiation temperature and fission density of the fuel particles for the TEM sample are estimated to be approximately ~110 degrees C and 5.4 x 10-21 f/cm3. The characterization was performed using a 200KV TEM with a LaB6 filament. Detailed microstructural information along with composition analysis is obtained. The results and their implication on the performance of this silicide fuel are discussed.

  14. Radiosensitization of Human Leukemic HL-60 Cells by ATR Kinase Inhibitor (VE-821): Phosphoproteomic Analysis

    PubMed Central

    Šalovská, Barbora; Fabrik, Ivo; Ďurišová, Kamila; Link, Marek; Vávrová, Jiřina; Řezáčová, Martina; Tichý, Aleš

    2014-01-01

    DNA damaging agents such as ionizing radiation or chemotherapy are frequently used in oncology. DNA damage response (DDR)—triggered by radiation-induced double strand breaks—is orchestrated mainly by three Phosphatidylinositol 3-kinase-related kinases (PIKKs): Ataxia teleangiectasia mutated (ATM), DNA-dependent protein kinase (DNA-PK) and ATM and Rad3-related kinase (ATR). Their activation promotes cell-cycle arrest and facilitates DNA damage repair, resulting in radioresistance. Recently developed specific ATR inhibitor, VE-821 (3-amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide), has been reported to have a significant radio- and chemo-sensitizing effect delimited to cancer cells (largely p53-deficient) without affecting normal cells. In this study, we employed SILAC-based quantitative phosphoproteomics to describe the mechanism of the radiosensitizing effect of VE-821 in human promyelocytic leukemic cells HL-60 (p53-negative). Hydrophilic interaction liquid chromatography (HILIC)-prefractionation with TiO2-enrichment and nano-liquid chromatography—tandem mass spectrometry (LC-MS/MS) analysis revealed 9834 phosphorylation sites. Proteins with differentially up-/down-regulated phosphorylation were mostly localized in the nucleus and were involved in cellular processes such as DDR, all phases of the cell cycle, and cell division. Moreover, sequence motif analysis revealed significant changes in the activities of kinases involved in these processes. Taken together, our data indicates that ATR kinase has multiple roles in response to DNA damage throughout the cell cycle and that its inhibitor VE-821 is a potent radiosensitizing agent for p53-negative HL-60 cells. PMID:25003641

  15. Infrared attenuated total reflection (IR-ATR) spectroscopy for detecting drugs in human saliva.

    PubMed

    Hans, Kerstin M-C; Müller, Susanne; Sigrist, Markus W

    2012-06-01

    The consumption of drugs is of great concern worldwide. Various drug tests for humans have been developed but there is no compact and easy-to-use test device available yet for direct semi-quantitative drug testing in the field. We suggest using attenuated total reflection (ATR) infrared spectroscopy as a sensing method to analyze human saliva samples with respect to drugs. In this paper, we present ATR spectra in the infrared range between 2300 and 900 cm(-1) as a first step towards such a device. We emphasize the common drug cocaine and its metabolites and investigate the problems of spectral interferences of selected diluents, masking agents, common medication, and soft drinks. Furthermore, spectra of saliva samples are recorded and a time-dependent change of the spectral signatures after alcohol consumption is presented. To the best of our knowledge, it is the first time that not only spectra of the drug of interest (cocaine) dissolved in water and in saliva but also spectra of interfering compounds possibly present in the saliva sample of a tested subject are discussed. This paper presents the most appropriate spectral range for strong cocaine absorption (including its metabolites) and minimum interference by the investigated substances. This spectral window is found to be between 1800 and 1710 cm(-1). In addition, we demonstrate the feasibility to identify cocaine in saliva at a concentration of 0.020 mg/ml with IR-ATR-spectroscopy without any separation or extraction procedures. For example, this technique could also be applied for drug detection in waste water. Copyright © 2011 John Wiley & Sons, Ltd.

  16. ATR-FTIR investigation on the complexation of myo-inositol hexaphosphate with aluminum hydroxide.

    PubMed

    Guan, Xiao-Hong; Shang, Chii; Zhu, Jun; Chen, Guang-Hao

    2006-01-15

    The adsorption isotherm of and the pH effect on the adsorption of myo-inositol hexaphosphate (myo-IP6) on amorphous aluminum hydroxide was investigated. It was found that the adsorption isotherm of myo-IP6 on aluminum hydroxide could be well fitted with the Freundlich isotherm. The amount of myo-IP6 adsorbed remained almost constant in the range of pH 4.0 to 7.0, but it decreased considerably as the initial pH was over 7. The adsorption of myo-IP6 resulted in an increase in the pH level due to the release of OH(-) ions, which suggested that the adsorption of myo-IP6 on aluminum hydroxide was caused by a ligand exchange reaction. ATR-FTIR analysis of myo-IP6 in solution and adsorbed on aluminum hydroxide at different pH were performed. The ATR-FTIR investigation indicated that myo-IP6 was adsorbed onto aluminum hydroxide by forming inner-sphere complexes and adsorption facilitated the deprotonation of phosphate groups. The asymmetric vibration of the PO bond in AlPO(-)(3) appearing at a lower frequency than that in the terminal HPO(-)(3) indicated that Al bound to the O atom not as strongly as the H atom did. The ATR-FTIR investigation and theoretical calculation (with the Gaussian 03 program) revealed that three of the six phosphate groups in myo-IP6 molecules were bound to aluminum hydroxide while the other three remained free when myo-IP6 was adsorbed on aluminum hydroxide.

  17. Defining ATR solutions using affine transformations on a union of subspaces model

    NASA Astrophysics Data System (ADS)

    Hester, Charles F.; Risko, Kelly K. D.

    2012-05-01

    The ability to recognize a target in an image is an important problem for machine vision, surveillance systems, and military weapons. There are many "solutions" to an automatic target recognition (ATR) problem proposed by practitioners. Often the definition of the problem leads to multiple solutions due to the incompleteness of the definition. Solutions are also made approximate due to resource limitations. Issues concerning "best" solution and solution performance are very open issues, since problem definitions and solutions are ill-defined. Indeed from information based physical measurement theory such as found in the Minimum Description Length (MDL) the exact solution is intractable1. Generating some clarity in defining problems on restricted sets seems an appropriate approach for improving this vagueness in ATR definitions and solutions. Given that a one to one relationship between a physical system and the MDL exists, then this uniqueness allows that a solution can be defined by its description and a norm assigned to that description. Moreover, the solution can be characterized by a set of metrics that are based on the algorithmic information of the physical measurements. The MDL, however, is not a constructive theory, but solutions can be defined by concise problem descriptions. This limits the scope of the problem and we will take this approach here. The paper will start with a definition of an ATR problem followed by our proposal of a descriptive solution using a union of subspaces model of images as described below based on Lu and Do2. This solution uses the concept of informative representations3 implicitly which we review briefly. Then we will present some metrics to be used to characterize the solution(s) which we will demonstrate by a simple example. In the discussions following the example we will suggest how this fits in the context of present and future work.

  18. Modelling mercury accumulation in minerogenic peat combining FTIR-ATR spectroscopy and partial least squares (PLS)

    NASA Astrophysics Data System (ADS)

    Pérez-Rodríguez, Marta; Horák-Terra, Ingrid; Rodríguez-Lado, Luis; Martínez Cortizas, Antonio

    2016-11-01

    Despite its potential, infrared spectroscopy combined with multivariate statistics has been seldom used to model peat properties with environmental value, such us the concentration of potentially toxic metals. In this research, we applied attenuated total reflectance (ATR) Fourier-Transform Infrared (FTIR) spectroscopy to evaluate the ability of the technique to predict mercury concentrations in late-Pleistocene/Holocene peat from a minerogenic peatland from Minas Gerais (Brazil). Mercury concentrations were analysed using a Milestone DMA-80 analyzer and attenuated total reflectance FTIR-ATR was performed using a Gladi-ATR (Pike Technologies) in the mid IR spectrum (4000-400 cm- 1). Concentrations were modelled using principal components (PCR) and partial least squares regression (PLS). The performance of the models varied between moderate and very good (R2 0.67-0.90), with low RMSD values (0.35-1.06). A PLS model based on three latent vectors (LV1 to LV3) provided the best (R2 0.90, RMSD 0.35) results. LV1 reflected total organic matter content versus mineral matter (mainly quartz from local fluxes), LV2 was related to dust deposition from regional sources, and LV3 reflected peat organic matter decomposition. Compared to a previous investigation based on geochemical data, the spectroscopy-based PLS model performed better, but it has to be complemented with additional data (as δ13 C ratios) to reliably reproduce the changes of the factors controlling mercury accumulation over time. This, time- and cost-effective, methodology may help to develop multi-core approaches to study the within and between mire (of a similar type and area) variability in mercury accumulation, and probably also other peat properties.

  19. ROC analysis of ATR from SAR images using a model-based recognizer incorporating pose information

    NASA Astrophysics Data System (ADS)

    Cyganski, David; King, Brian M.; Vaz, Richard F.; Orr, John A.

    1995-06-01

    An automatic taget recognition (ATR) technique developed by the authors features analytically derived object models which are formed from entire image suites, yet are compact and allow a direct target recognition and pose determination procedure. In contrast to the pose-invariant information used to form the models in conventional approaches, view-dependent information is retained in the formation of the compact models for this new approach. All model-based ATR systems are confronted with the problem of image variation as a function of viewing angle. This problem can be addressed by use of an exhaustive library of views, at the expense of a large suite of literal images and a computationally intensive search-based recognition process. Means for overcoming these storage and processing obstacles have traditionally invloved some type of view-independent target representation, often developed from some composite view of the target over the viewing angles of interest. This results in a much more compact target model, and a more direct recognition process. Unfortunately, the gains in storage and computational requirements of these invariant algorithms come at the price of diminished target discrimination capability. The new algorithm incorporates pose as a fundamental parameter which is solved for as part of the recognition process, and does not discard the pose-related information which is relevant to target recognition. In this paper, the newly developed technique is applied to synthetic aperture radar images to develop receiver operating characteristic curves in the presence of both multiplicative noise and clutter. Comparative curves are also developed for a conventional generalized quandratic classifier ATR system.

  20. Quantification of minerals from ATR-FTIR spectra with spectral interferences using the MRC method

    NASA Astrophysics Data System (ADS)

    Bosch-Reig, Francisco; Gimeno-Adelantado, José Vicente; Bosch-Mossi, Francisco; Doménech-Carbó, Antonio

    2017-06-01

    A method for quantifying the individual components of mineral samples based on attenuated total reflectance - Fourier transform infrared spectroscopy (ATR-FTIR) is described, extending the constant ratio (CR) method to analytes absorbing in a common range of wavenumbers. Absorbance values in the spectral region where the analytes absorb relative to the absorbance of an internal standard absorbing at a wavenumber where the analytes do not absorb, permits the quantification of N analytes using measurements at N fixed wavenumbers. The method was tested for mixtures of albite, orthoclase, kaolin and quartz.

  1. Characterisation Of Polysacharides And Lipids From Selected Green Algae Species By FTIR-ATR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Bartošová, Alica; Blinová, Lenka; Gerulová, Kristína

    2015-06-01

    Fourier transform infrared (FTIR) spectroscopy was used in this study to identify and determine spectral features of Chromochloris zofingiensis (Dönz) Fucíková et L.A. Lewis (SAG 211-14, Gottingen, Germany), Acutodesmus obliguus (Turpin) Hegewald (SAG 276-1, Gottingen, Germany) and Chlorella sorokiniana (K. Brandt) Pröschold et Darienko (SAG 211-40c, Gottingen, Germany). Polysaccharides and lipids from these three algae species were determined using Fourier Transformed Infrared Spectroscopy (FTIR) with ATR accessory with diamante crystal in spectral range from 400 - 4000 cm-1 and resolution 4.

  2. Testing a High-Sensitivity ATR FTIR Water Monitor for Ionic CWA Breakdown Products

    DTIC Science & Technology

    2006-05-31

    coating material(s) Hug5 SO42− 1 µM hematite Blesa6 carboxylates 1 µM TiO2 Martin7 carboxylates 10 µM (LOD) hematite Elzinga8 SO42− 30 µM goethite...better and were used as received from Sigma/Aldrich or similar vendors. The polyalkylated ferrocenium salts 1,1′,3,3′-tetrakis(2- methyl -2-nonyl...probe is shown in black. A blank spectrum is shown in blue , and the baseline (y = 0) is shown in red. Figure 9 (right). ATR-FTIR spectrum of the

  3. Registration of heavy metal ions and pesticides with ATR planar waveguide enzyme sensors

    NASA Astrophysics Data System (ADS)

    Nabok, Alexei; Haron, Saharudin; Ray, Asim

    2004-11-01

    The proposed novel type of enzyme optical sensors is based on a combination of SiO2/Si3N4/SiO2 planar waveguide ATR (attenuated total reflection) transducer, fabricated by standard silicon planar technology, with the composite polyelectrolyte self-assembled coating containing both organic chromophores and enzyme molecules. Such devices were deployed to monitor typical industrial and agricultural water pollutants, such as heavy metal ions and pesticides, acting as inhibitors of enzyme reactions. The sensitivity of registration of these pollutants in the range of 1 ppb was achieved. The use of different enzymes in the sensitive membrane provides a background for pattern recognition of the above pollutants.

  4. Optical pattern recognition and Al algorithms and architectures for automatic target recognition (ATR) and computer vision

    NASA Astrophysics Data System (ADS)

    Casasent, David

    1987-04-01

    Optical Pattern Recognition has provided many attractive algorithms and architecture for advanced use in Automatic Target Recognition (ATR) and computer vision. This work is reviewed and highlighted in this paper. Attractive aspects of all of this research are: its attention to distortion-invariant, multi-target object recognition and the extensive testing which has been performed of these various architectures on large databases, as well as the design and fabrication of several quite compact optical processing architectures. Recent Artificial Intelligence (AI) techniques promise to further advance optical processing. These issues are summarized herein.

  5. Structure-Activity Relations In Enzymes: An Application Of IR-ATR Modulation Spectroscopy

    NASA Astrophysics Data System (ADS)

    Fringeli, Urs P.; Ahlstrom, Peter; Vincenz, Claudius; Fringeli, Marianna

    1985-12-01

    Relations between structure and specific activity in immobilized acetylcholinesterase (ACNE) have been studied by means of pH- and Ca++-modulation technique combined with attenuated total reflection (ATR) infrared (IR) spectroscopy and enzyme activity measurement. Periodic modulation of pH and Ca++-concentration enabled a periodic on-off switching of about 40% of the total enzyme activity. It was found that about 0.5 to 1% of the amino acids were involved in this process. These 15 to 30 amino acids assumed antiparallel pleated sheet structure in the inhibited state and random and/or helical structure in the activated state.

  6. Towards distributed ATR using subjective logic combination rules with a swarm of UAVs

    NASA Astrophysics Data System (ADS)

    O'Hara, Stephen; Simon, Michael; Zhu, Qiuming

    2007-04-01

    In this paper, we present our initial findings demonstrating a cost-effective approach to Aided Target Recognition (ATR) employing a swarm of inexpensive Unmanned Aerial Vehicles (UAVs). We call our approach Distributed ATR (DATR). Our paper describes the utility of DATR for autonomous UAV operations, provides an overview of our methods, and the results of our initial simulation-based implementation and feasibility study. Our technology is aimed towards small and micro UAVs where platform restrictions allow only a modest quality camera and limited on-board computational capabilities. It is understood that an inexpensive sensor coupled with limited processing capability would be challenged in deriving a high probability of detection (P d) while maintaining a low probability of false alarms (P fa). Our hypothesis is that an evidential reasoning approach to fusing the observations of multiple UAVs observing approximately the same scene can raise the P d and lower the P fa sufficiently in order to provide a cost-effective ATR capability. This capability can lead to practical implementations of autonomous, coordinated, multi-UAV operations. In our system, the live video feed from a UAV is processed by a lightweight real-time ATR algorithm. This algorithm provides a set of possible classifications for each detected object over a possibility space defined by a set of exemplars. The classifications for each frame within a short observation interval (a few seconds) are used to generate a belief statement. Our system considers how many frames in the observation interval support each potential classification. A definable function transforms the observational data into a belief value. The belief value, or opinion, represents the UAV's belief that an object of the particular class exists in the area covered during the observation interval. The opinion is submitted as evidence in an evidential reasoning system. Opinions from observations over the same spatial area will have

  7. PLS-LS-SVM based modeling of ATR-IR as a robust method in detection and qualification of alprazolam.

    PubMed

    Parhizkar, Elahehnaz; Ghazali, Mohammad; Ahmadi, Fatemeh; Sakhteman, Amirhossein

    2017-02-15

    According to the United States pharmacopeia (USP), Gold standard technique for Alprazolam determination in dosage forms is HPLC, an expensive and time-consuming method that is not easy to approach. In this study chemometrics assisted ATR-IR was introduced as an alternative method that produce similar results in fewer time and energy consumed manner. Fifty-eight samples containing different concentrations of commercial alprazolam were evaluated by HPLC and ATR-IR method. A preprocessing approach was applied to convert raw data obtained from ATR-IR spectra to normal matrix. Finally, a relationship between alprazolam concentrations achieved by HPLC and ATR-IR data was established using PLS-LS-SVM (partial least squares least squares support vector machines). Consequently, validity of the method was verified to yield a model with low error values (root mean square error of cross validation equal to 0.98). The model was able to predict about 99% of the samples according to R(2) of prediction set. Response permutation test was also applied to affirm that the model was not assessed by chance correlations. At conclusion, ATR-IR can be a reliable method in manufacturing process in detection and qualification of alprazolam content. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Binding of a biosynthetic intermediate to AtrA modulates the production of lidamycin by Streptomyces globisporus.

    PubMed

    Li, Xingxing; Yu, Tengfei; He, Qing; McDowall, Kenneth J; Jiang, Bingya; Jiang, Zhibo; Wu, Linzhuan; Li, Guangwei; Li, Qinglian; Wang, Songmei; Shi, Yuanyuan; Wang, Lifei; Hong, Bin

    2015-06-01

    The control of secondary production in streptomycetes involves the funneling of environmental and physiological signals to the cluster-situated (transcriptional) regulators (CSRs) of the biosynthetic genes. For some systems, the binding of biosynthetic products to the CSR has been shown to provide negative feedback. Here we show for the production of lidamycin (C-1027), a clinically relevant antitumor agent, by Streptomyces globisporus that negative feedback can extend to a point higher in the regulatory cascade. We show that the DNA-binding activity of the S. globisporus orthologue of AtrA, which was initially described as a transcriptional activator of actinorhodin biosynthesis in S. coelicolor, is inhibited by the binding of heptaene, a biosynthetic intermediate of lidamycin. Additional experiments described here show that S. globisporus AtrA binds in vivo as well as in vitro to the promoter region of the gene encoding SgcR1, one of the CSRs of lidamycin production. The feedback to the pleiotropic regulator AtrA is likely to provide a mechanism for coordinating the production of lidamycin with that of other secondary metabolites. The activity of AtrA is also regulated by actinorhodin. As AtrA is evolutionarily conserved, negative feedback of the type described here may be widespread within the streptomycetes.

  9. PLS-LS-SVM based modeling of ATR-IR as a robust method in detection and qualification of alprazolam

    NASA Astrophysics Data System (ADS)

    Parhizkar, Elahehnaz; Ghazali, Mohammad; Ahmadi, Fatemeh; Sakhteman, Amirhossein

    2017-02-01

    According to the United States pharmacopeia (USP), Gold standard technique for Alprazolam determination in dosage forms is HPLC, an expensive and time-consuming method that is not easy to approach. In this study chemometrics assisted ATR-IR was introduced as an alternative method that produce similar results in fewer time and energy consumed manner. Fifty-eight samples containing different concentrations of commercial alprazolam were evaluated by HPLC and ATR-IR method. A preprocessing approach was applied to convert raw data obtained from ATR-IR spectra to normal matrix. Finally, a relationship between alprazolam concentrations achieved by HPLC and ATR-IR data was established using PLS-LS-SVM (partial least squares least squares support vector machines). Consequently, validity of the method was verified to yield a model with low error values (root mean square error of cross validation equal to 0.98). The model was able to predict about 99% of the samples according to R2 of prediction set. Response permutation test was also applied to affirm that the model was not assessed by chance correlations. At conclusion, ATR-IR can be a reliable method in manufacturing process in detection and qualification of alprazolam content.

  10. Fuel compositions

    SciTech Connect

    Zaweski, E.F.; Niebylski, L.M.

    1986-08-05

    This patent describes distillate fuel for indirect injection compression ignition engines containing, in an amount sufficient to minimize coking, especially throttling nozzle coking in the prechambers or swirl chambers of indirect injection compression ignition engines operated on such fuel, at least the combination of (i) organic nitrate ignition accelerator and (ii) an esterified cycle dehydration product of sorbitol which, when added to the fuel in combination with the organic nitrate ignition accelerator minimizes the coking.

  11. Fuel cells 101

    SciTech Connect

    Hirschenhofer, J.H.

    1999-07-01

    This paper discusses the various types of fuel cells, the importance of cell voltage, fuel processing for natural gas, cell stacking, fuel cell plant description, advantages and disadvantages of the types of fuel cells, and applications. The types covered include: polymer electrolyte fuel cell, alkaline fuel cell, phosphoric acid fuel cell; molten carbonate fuel cell, and solid oxide fuel cell.

  12. Motor fuel

    SciTech Connect

    Burns, L.D.

    1982-07-13

    Liquid hydrocarbon fuel compositions are provided containing antiknock quantities of ashless antiknock agents comprising selected furyl compounds including furfuryl alcohol, furfuryl amine, furfuryl esters, and alkyl furoates.

  13. Fuel dehazers

    SciTech Connect

    Lyons, W.R.

    1986-03-01

    Hazy fuels can be caused by the emulsification of water into the fuel during refining, blending, or transportation operations. Detergent additive packages used in gasoline tend to emulsify water into the fuel. Fuels containing water haze can cause corrosion and contamination, and support microbiological growth. This results in problems. As the result of these problems, refiners, marketers, and product pipeline companies customarily have haze specifications. The haze specification may be a specific maximum water content or simply ''bright and clear'' at a specified temperature.

  14. Alternative fuels

    SciTech Connect

    Not Available

    1991-07-01

    This paper presents the preliminary results of a review, of the experiences of Brazil, Canada, and New Zealand, which have implemented programs to encourage the use of alternative motor fuels. It will also discuss the results of a separate completed review of the Department of Energy's (DOE) progress in implementing the Alternative Motor Fuels Act of 1988. The act calls for, among other things, the federal government to use alternative-fueled vehicles in its fleet. The Persian Gulf War, environmental concerns, and the administration's National Energy Strategy have greatly heightened interest in the use of alternative fuels in this country.

  15. Laccase/AuAg Hybrid Glucose Microfludic Fuel Cell

    NASA Astrophysics Data System (ADS)

    López-González, B.; Cuevas-Muñiz, F. M.; Guerra-Balcázar, M.; Déctor, A.; Arjona, N.; Ledesma-García, J.; Arriaga, L. G.

    2013-12-01

    In this work a hybrid microfluidic fuel cell was fabricated and evaluated with a AuAg/C bimetallic material for the anode and an enzymatic cathode. The cathodic catalyst was prepared adsorbing laccase and ABTS on Vulcan carbon (Lac-ABTS/C). This material was characterized by FTIR-ATR, the results shows the presence of absorption bands corresponding to the amide bounds. The electrochemical evaluation for the materials consisted in cyclic voltammetry (CV). The glucose electrooxidation reaction in AuAg/C occurs around - 0.3 V vs. NHE. Both electrocatalytic materials were placed in a microfluidic fuel cell. The fuel cell was fed with PBS pH 5 oxygen saturated solution in the cathodic compartment and 5 mM glucose + 0.3 M KOH in the anodic side. Several polarization curves were performed and the maximum power density obtained was 0.3 mWcm-2 .

  16. Investigation on the adsorption characteristics of sodium benzoate and taurine on gold nanoparticle film by ATR-FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Kumar, Naveen; Thomas, S.; Tokas, R. B.; Kshirsagar, R. J.

    2014-01-01

    Fourier transform infrared (FTIR) spectroscopic studies of sodium benzoate and taurine adsorbed on gold nanoparticle (AuNp) film on silanised glass slides have been studied by attenuated total reflection technique (ATR). The surface morphology of the AuNp films has been measured by Atomic Force Microscopy. The ATR spectra of sodium benzoate and taurine deposited on AuNp film are compared with ATR spectra of their powdered bulk samples. A new red-shifted band appeared along with the symmetric and asymmetric stretches of carboxylate group of sodium benzoate leading to a broadening of the above peaks. Similar behavior is also seen in the case of symmetric and asymmetric stretches of sulphonate group of taurine. The results indicate presence of both chemisorbed and physisorbed layers of both sodium benzoate and taurine on the AuNp film with bottom layer chemically bound to AuNp through carboxylate and sulphonate groups respectively.

  17. Attenuated Total Reflection Surface-Enhanced Infrared Absorption (ATR SEIRA) Spectroscopy for the Analysis of Fatty Acids on Silver Nanoparticles.

    PubMed

    Kato, Yuichi; Kikugawa, Masashi; Sudo, Eiichi

    2017-09-01

    The application of attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR SEIRA) to the analysis of fatty acids on silver nanoparticles was investigated. Attenuated total reflection measurements using four types of internal reflection elements (IREs)-zinc selenide, diamond, silicon, and germanium-were performed for silver nanoparticles modified with fatty acids, and germanium IRE was shown to be suitable for the analysis of silver nanoparticles, even when the sample had a high refractive index. Fatty acids coating the silver nanoparticles could be directly identified by SEIRA enhancement, because both symmetric carboxylate stretching vibration and methylene wagging vibration were strongly detected. Furthermore, the peak positions for methylene wagging vibration differed depending on the carbon number of the fatty acid, so that information from the ATR SEIRA spectra makes it possible to identify substances coating silver nanoparticles. Therefore, ATR SEIRA would appear to have significant potential as a technique for the identification of substances coated on metal nanoparticle surfaces.

  18. Molecular orientation of molybdate ions adsorbed on goethite nanoparticles revealed by polarized in situ ATR-IR spectroscopy

    NASA Astrophysics Data System (ADS)

    Davantès, Athénaïs; Lefèvre, Grégory

    2016-11-01

    The speciation of species adsorbed on nanoparticles is a major concern for several fields, as environmental pollution and remediation, surface functionalization, or catalysis. Attenuated total reflectance infrared spectroscopy (ATR-IR) was amongst the rare methods able to give in situ information about the geometry of surface complexes on nanoparticles. A new possibility using this technique is illustrated here with the MoO42 -/goethite system. Using deuterated goethite to avoid spectral interferences, adsorption of molybdate ions on a spontaneous oriented film of nanoparticles has been followed using a polarized infrared beam. From the decomposition of spectra in the x, y and z directions, a monodentate surface complex on the {101} faces has been found as the most probable geometry. This result demonstrates that polarized ATR-IR allows to characterize in more details adsorption mode at the atomic scale, in comparison with usual ATR-IR spectroscopy.

  19. Substrate contributions in micro-ATR of thin samples: implications for analysis of cells, tissue and biological fluids.

    PubMed

    Bassan, Paul; Sachdeva, Ashwin; Lee, Joe; Gardner, Peter

    2013-07-21

    Low-e microscope slides are a common substrate for biological samples. Typically they are used for transflection infrared microspectroscopy but increasingly they are also being used for micro-ATR experiments since it is assumed that the FTIR-ATR absorbance spectra of cells and tissue on low-e substrates will not contain any spectral contributions from the substrate materials. This, in part, is due to the expectation that all the infrared light will be reflected at the highly reflective surface. At low sample thicknesses, however (e.g. less than 2 μm) the electric field does indeed penetrate through the substrate layers and undergoes absorption, from the glass supporting layer making up the majority of the slide. In this paper we show experimental evidence of the substrate contributions in ATR spectra and also a theoretical model giving insight into the spectral contributions of the substrate as a function of sample thickness.

  20. Validation of the Physics Analysis used to Characterize the AGR-1 TRISO Fuel Irradiation Test

    SciTech Connect

    Sterbentz, James W.; Harp, Jason M.; Demkowicz, Paul A.; Hawkes, Grant L.; Chang, Gray S.

    2015-05-01

    The results of a detailed physics depletion calculation used to characterize the AGR-1 TRISO-coated particle fuel test irradiated in the Advanced Test Reactor (ATR) at the Idaho National Laboratory are compared to measured data for the purpose of validation. The particle fuel was irradiated for 13 ATR power cycles over three calendar years. The physics analysis predicts compact burnups ranging from 11.30-19.56% FIMA and cumulative neutron fast fluence from 2.21?4.39E+25 n/m2 under simulated high-temperature gas-cooled reactor conditions in the ATR. The physics depletion calculation can provide a full characterization of all 72 irradiated TRISO-coated particle compacts during and post-irradiation, so validation of this physics calculation was a top priority. The validation of the physics analysis was done through comparisons with available measured experimental data which included: 1) high-resolution gamma scans for compact activity and burnup, 2) mass spectrometry for compact burnup, 3) flux wires for cumulative fast fluence, and 4) mass spectrometry for individual actinide and fission product concentrations. The measured data are generally in very good agreement with the calculated results, and therefore provide an adequate validation of the physics analysis and the results used to characterize the irradiated AGR-1 TRISO fuel.

  1. A high resolution and high speed 3D imaging system and its application on ATR

    NASA Astrophysics Data System (ADS)

    Lu, Thomas T.; Chao, Tien-Hsin

    2006-04-01

    The paper presents an advanced 3D imaging system based on a combination of stereo vision and light projection methods. A single digital camera is used to take only one shot of the object and reconstruct the 3D model of an object. The stereo vision is achieved by employing a prism and mirror setup to split the views and combine them side by side in the camera. The advantage of this setup is its simple system architecture, easy synchronization, fast 3D imaging speed and high accuracy. The 3D imaging algorithms and potential applications are discussed. For ATR applications, it is critically important to extract maximum information for the potential targets and to separate the targets from the background and clutter noise. The added dimension of a 3D model provides additional features of surface profile, range information of the target. It is capable of removing the false shadow from camouflage and reveal the 3D profile of the object. It also provides arbitrary viewing angles and distances for training the filter bank for invariant ATR. The system architecture can be scaled to take large objects and to perform area 3D modeling onboard a UAV.

  2. AFM combined to ATR-FTIR reveals Candida cell wall changes under caspofungin treatment.

    PubMed

    Quilès, Fabienne; Accoceberry, Isabelle; Couzigou, Célia; Francius, Grégory; Noël, Thierry; El-Kirat-Chatel, Sofiane

    2017-09-21

    Fungal pathogens from Candida genus are responsible for severe life-threatening infections and the antifungal arsenal is still limited. Caspofungin, an antifungal drug used for human therapy, acts as a blocking agent of the cell wall synthesis by inhibiting the β-1,3-glucan-synthase encoded by FKS genes. Despite its efficiency, the number of genetic mutants that are resistant to caspofungin is increasing. An important challenge to improve antifungal therapy is to understand cellular phenomenon that are associated with drug resistance. Here we used atomic force microscopy (AFM) combined to Fourier transform infrared spectroscopy in attenuated total reflection mode (ATR-FTIR) to decipher the effect of low and high drug concentration on the morphology, mechanics and cell wall composition of two Candida strains, one susceptible and one resistant to caspofungin. Our results confirm that caspofungin induces a dramatic cell wall remodelling via activation of stress responses, even at high drug concentration. Additionally, we highlighted unexpected changes related to drug resistance, suggesting that caspofungin resistance associated with FKS gene mutations comes from a combination of effects: (i) an overall remodelling of yeast cell wall composition; and (ii) cell wall stiffening through chitin synthesis. This work demonstrates that AFM combined to ATR-FTIR is a valuable approach to understand at the molecular scale the biological mechanisms associated with drug resistance.

  3. In-column ATR-FTIR spectroscopy to monitor affinity chromatography purification of monoclonal antibodies

    NASA Astrophysics Data System (ADS)

    Boulet-Audet, Maxime; Kazarian, Sergei G.; Byrne, Bernadette

    2016-07-01

    In recent years many monoclonal antibodies (mAb) have entered the biotherapeutics market, offering new treatments for chronic and life-threatening diseases. Protein A resin captures monoclonal antibody (mAb) effectively, but the binding capacity decays over repeated purification cycles. On an industrial scale, replacing fouled Protein A affinity chromatography resin accounts for a large proportion of the raw material cost. Cleaning-in-place (CIP) procedures were developed to extend Protein A resin lifespan, but chromatograms cannot reliably quantify any remaining contaminants over repeated cycles. To study resin fouling in situ, we coupled affinity chromatography and Fourier transform infrared (FTIR) spectroscopy for the first time, by embedding an attenuated total reflection (ATR) sensor inside a micro-scale column while measuring the UV 280 nm and conductivity. Our approach quantified the in-column protein concentration in the resin bed and determined protein conformation. Our results show that Protein A ligand leached during CIP. We also found that host cell proteins bound to the Protein A resin even more strongly than mAbs and that typical CIP conditions do not remove all fouling contaminants. The insights derived from in-column ATR-FTIR spectroscopic monitoring could contribute to mAb purification quality assurance as well as guide the development of more effective CIP conditions to optimise resin lifespan.

  4. In-column ATR-FTIR spectroscopy to monitor affinity chromatography purification of monoclonal antibodies

    PubMed Central

    Boulet-Audet, Maxime; Kazarian, Sergei G.; Byrne, Bernadette

    2016-01-01

    In recent years many monoclonal antibodies (mAb) have entered the biotherapeutics market, offering new treatments for chronic and life-threatening diseases. Protein A resin captures monoclonal antibody (mAb) effectively, but the binding capacity decays over repeated purification cycles. On an industrial scale, replacing fouled Protein A affinity chromatography resin accounts for a large proportion of the raw material cost. Cleaning-in-place (CIP) procedures were developed to extend Protein A resin lifespan, but chromatograms cannot reliably quantify any remaining contaminants over repeated cycles. To study resin fouling in situ, we coupled affinity chromatography and Fourier transform infrared (FTIR) spectroscopy for the first time, by embedding an attenuated total reflection (ATR) sensor inside a micro-scale column while measuring the UV 280 nm and conductivity. Our approach quantified the in-column protein concentration in the resin bed and determined protein conformation. Our results show that Protein A ligand leached during CIP. We also found that host cell proteins bound to the Protein A resin even more strongly than mAbs and that typical CIP conditions do not remove all fouling contaminants. The insights derived from in-column ATR-FTIR spectroscopic monitoring could contribute to mAb purification quality assurance as well as guide the development of more effective CIP conditions to optimise resin lifespan. PMID:27470880

  5. Centromeric DNA replication reconstitution reveals DNA loops and ATR checkpoint suppression.

    PubMed

    Aze, Antoine; Sannino, Vincenzo; Soffientini, Paolo; Bachi, Angela; Costanzo, Vincenzo

    2016-06-01

    Half of the human genome is made up of repetitive DNA. However, mechanisms underlying replication of chromosome regions containing repetitive DNA are poorly understood. We reconstituted replication of defined human chromosome segments using bacterial artificial chromosomes in Xenopus laevis egg extract. Using this approach we characterized the chromatin assembly and replication dynamics of centromeric alpha-satellite DNA. Proteomic analysis of centromeric chromatin revealed replication-dependent enrichment of a network of DNA repair factors including the MSH2-6 complex, which was required for efficient centromeric DNA replication. However, contrary to expectations, the ATR-dependent checkpoint monitoring DNA replication fork arrest could not be activated on highly repetitive DNA due to the inability of the single-stranded DNA binding protein RPA to accumulate on chromatin. Electron microscopy of centromeric DNA and supercoil mapping revealed the presence of topoisomerase I-dependent DNA loops embedded in a protein matrix enriched for SMC2-4 proteins. This arrangement suppressed ATR signalling by preventing RPA hyper-loading, facilitating replication of centromeric DNA. These findings have important implications for our understanding of repetitive DNA metabolism and centromere organization under normal and stressful conditions.

  6. Rapid detection of melamine adulteration in dairy milk by SB-ATR-Fourier transform infrared spectroscopy.

    PubMed

    Jawaid, Sana; Talpur, Farah N; Sherazi, S T H; Nizamani, Shafi M; Khaskheli, Abid A

    2013-12-01

    Melamine is a nitrogenous chemical substance used principally as a starting material for the manufacture of synthetic resins. Due to its very high proportion of nitrogen melamine has been added illegitimately to foods and feeds to increase the measured protein content, which determines the value of the product. These issues prompted private as well as governmental laboratories to develop methods for the analysis of melamine in a wide variety of food products and ingredients. Owing to this fact present study is aimed to use single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared spectroscopy (FTIR) method as an effective rapid tool for the detection and quantification of melamine in milk (liquid and powder). Partial least-squares (PLS) models were established for correlating spectral data to melamine concentration with R(2)>0.99, and RMSEC 0.370. Linear calibration curves were obtained over the calibration range of 25-0.0625%. The LOD and LOQ of the method was 0.00025% (2.5 ppm) and 0.0015% (15 ppm) respectively. Proposed SB-ATR-FTIR method requires little or no sample preparation with an assay time of 1-2 min. Copyright © 2013. Published by Elsevier Ltd.

  7. Characterization of Printing Inks Using DART-Q-TOF-MS and Attenuated Total Reflectance (ATR) FTIR.

    PubMed

    Williamson, Rhett; Raeva, Anna; Almirall, Jose R

    2016-05-01

    The rise in improved and widely accessible printing technology has resulted in an interest to develop rapid and minimally destructive chemical analytical techniques that can characterize printing inks for forensic document analysis. Chemical characterization of printing inks allows for both discrimination of inks originating from different sources and the association of inks originating from the same source. Direct analysis in real-time mass spectrometry (DART-MS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were used in tandem to analyze four different classes of printing inks: inkjets, toners, offset, and intaglio. A total of 319 samples or ~ 80 samples from each class were analyzed directly on a paper substrate using the two methods. DART-MS was found to characterize the semi-volatile polymeric vehicle components, while ATR-FTIR provided chemical information associated with the bulk components of these inks. Complimentary data results in improved discrimination when both techniques are used in succession resulting in >96% discrimination for all toners, 95% for all inkjets, >92% for all offset, and >54% for all intaglio inks. © 2016 American Academy of Forensic Sciences.

  8. Analytical performance evaluation of SAR ATR with inaccurate or estimated models

    NASA Astrophysics Data System (ADS)

    DeVore, Michael D.

    2004-09-01

    Hypothesis testing algorithms for automatic target recognition (ATR) are often formulated in terms of some assumed distribution family. The parameter values corresponding to a particular target class together with the distribution family constitute a model for the target's signature. In practice such models exhibit inaccuracy because of incorrect assumptions about the distribution family and/or because of errors in the assumed parameter values, which are often determined experimentally. Model inaccuracy can have a significant impact on performance predictions for target recognition systems. Such inaccuracy often causes model-based predictions that ignore the difference between assumed and actual distributions to be overly optimistic. This paper reports on research to quantify the effect of inaccurate models on performance prediction and to estimate the effect using only trained parameters. We demonstrate that for large observation vectors the class-conditional probabilities of error can be expressed as a simple function of the difference between two relative entropies. These relative entropies quantify the discrepancies between the actual and assumed distributions and can be used to express the difference between actual and predicted error rates. Focusing on the problem of ATR from synthetic aperture radar (SAR) imagery, we present estimators of the probabilities of error in both ideal and plug-in tests expressed in terms of the trained model parameters. These estimators are defined in terms of unbiased estimates for the first two moments of the sample statistic. We present an analytical treatment of these results and include demonstrations from simulated radar data.

  9. Analytical characterization of polymers used in conservation and restoration by ATR-FTIR spectroscopy.

    PubMed

    Chércoles Asensio, Ruth; San Andrés Moya, Margarita; de la Roja, José Manuel; Gómez, Marisa

    2009-12-01

    In the last few decades many new polymers have been synthesized that are now being used in cultural heritage conservation. The physical and chemical properties and the long-term behaviors of these new polymers are determined by the chemical composition of the starting materials used in their synthesis along with the nature of the substances added to facilitate their production. The practical applications of these polymers depend on their composition and form (foam, film, sheets, pressure-sensitive adhesives, heat-seal adhesives, etc.). Some materials are used in restoration works and others for the exhibition, storage and transport of works of art. In all cases, it is absolutely necessary to know their compositions. Furthermore, many different materials that are manufactured for other objectives are also used for conservation and restoration. The technical information about the materials provided by the manufacturer is usually incomplete, so it is necessary to analytically characterize such materials. FTIR spectrometry is widely used for polymer identification, and, more recently, ATR-FTIR has been shown to give excellent results. This paper reports the ATR-FTIR analysis of samples of polymeric materials used in the conservation of artworks. These samples were examined directly in the solid material without sample preparation.

  10. ATM Deficiency Is Associated with Sensitivity to PARP1- and ATR Inhibitors in Lung Adenocarcinoma.

    PubMed

    Schmitt, Anna; Knittel, Gero; Welcker, Daniela; Yang, Tsun-Po; George, Julie; Nowak, Michael; Leeser, Uschi; Büttner, Reinhard; Perner, Sven; Peifer, Martin; Reinhardt, Hans Christian

    2017-06-01

    Defects in maintaining genome integrity are a hallmark of cancer. The DNA damage response kinase ATM is frequently mutated in human cancer, but the significance of these events to chemotherapeutic efficacy has not been examined deeply in whole organism models. Here we demonstrate that bi-allelic Atm deletion in mouse models of Kras-mutant lung adenocarcinoma does not affect cisplatin responses. In marked contrast, Atm-deficient tumors displayed an enhanced response to the topoisomerase-II poison etoposide. Moreover, Atm-deficient cells and tumors were sensitive to the PARP inhibitor olaparib. This actionable molecular addiction to functional PARP1 signaling was preserved in models that were proficient or deficient in p53, resembling standard or high-risk genetic constellations, respectively. Atm deficiency also markedly enhanced sensitivity to the ATR inhibitor VE-822. Taken together, our results provide a functional rationale to profile human tumors for disabling ATM mutations, particularly given their impact on PARP1 and ATR inhibitors. Cancer Res; 77(11); 3040-56. ©2017 AACR. ©2017 American Association for Cancer Research.

  11. Universal method for protein immobilization on chemically functionalized germanium investigated by ATR-FTIR difference spectroscopy.

    PubMed

    Schartner, Jonas; Güldenhaupt, Jörn; Mei, Bastian; Rögner, Matthias; Muhler, Martin; Gerwert, Klaus; Kötting, Carsten

    2013-03-13

    Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy allows a detailed analysis of surface attached molecules, including their secondary structure, orientation, and interaction with small molecules in the case of proteins. Here, we present a universal immobilization technique on germanium for all oligo-histidine-tagged proteins. For this purpose, new triethoxysilane derivates were developed: we synthesized a linker-silane with a succinimidyl ester as amine-reactive headgroup and a matrix-silane with an unreactive ethylene glycol group. A new methodology for the attachment of triethoxysilanes on germanium was established, and the surface was characterized by ATR-FTIR and X-ray photoelectron spectroscopy. In the next step, the succinimidyl ester was reacted with aminonitrilotriacetic acid. Subsequently, Ni(2+) was coordinated to form Ni-nitrilotriacetic acid for His-tag binding. The capability of the functionalized surface was demonstrated by experiments using the small GTPase Ras and photosystem I (PS I). The native binding of the proteins was proven by difference spectroscopy, which probes protein function. The function of Ras as molecular switch was demonstrated by a beryllium trifluoride anion titration assay, which allows observation of the "on" and "off" switching of Ras at atomic resolution. Furthermore, the activity of immobilized PS I was proven by light-induced difference spectroscopy. Subsequent treatment with imidazole removes attached proteins, enabling repeated binding. This universal technique allows specific attachment of His-tagged proteins and a detailed study of their function at the atomic level using FTIR difference spectroscopy.

  12. Phosphoproteomics Reveals Distinct Modes of Mec1/ATR Signaling During DNA Replication

    PubMed Central

    de Oliveira, Francisco Meirelles Bastos; Kim, Dongsung; Cussiol, Jose Renato; Das, Jishnu; Jeong, Min Cheol; Doerfler, Lillian; Schmidt, Kristina Hildegard; Yu, Haiyuan; Smolka, Marcus Bustamante

    2015-01-01

    SUMMARY The Mec1/Tel1 kinases (human ATR/ATM) play numerous roles in the DNA replication stress response. Despite the multi-functionality of these kinases, studies of their in vivo action have mostly relied on a few well-established substrates. Here we employed a combined genetic-phosphoproteomic approach to monitor Mec1/Tel1 signaling in a systematic, unbiased and quantitative manner. Unexpectedly, we find that Mec1 is highly active during normal DNA replication, at levels comparable or higher than Mec1’s activation state induced by replication stress. This “replication-correlated” mode of Mec1 action requires the 9-1-1 clamp and the Dna2 lagging-strand factor, and is distinguishable from Mec1’s action in activating the downstream kinase Rad53. We propose that Mec1/ATR performs key functions during ongoing DNA synthesis that are distinct from their canonical checkpoint role during replication stress. PMID:25752575

  13. Evanescent wave absorption measurements of corroded materials using ATR and optical fibers

    NASA Astrophysics Data System (ADS)

    Namkung, Juock; Hoke, Mike; Schwartz, Andy

    2011-06-01

    The purpose of this research effort is to develop an in-situ corrosion sensing capability. The technique will permit detection of corrosion on and within aircraft structures. This includes component junctions that are susceptible to corrosion but which are not accessible for visual inspection. The prototype experimental configuration we are developing includes long wave infrared transmitting optical fiber probes interfaced with a Fourier Transform Infrared (FTIR) interferometer for evanescent wave absorption spectroscopic measurements. The mature and fielded technique will allow periodic remote sensing for detection of corrosion and for general onboard aircraft structural health monitoring. An experimental setup using an Attenuated Total Reflection (ATR) crystal integrated with an FTIR spectrometer has been assembled. Naturally occurring corrosion including Aluminum Hydroxide [Al(OH)3] is one of the main corrosion products of aluminum the principle structural metal of aircraft. Absorption spectra of our model corrosion product, pure Al(OH)3, have been collected with this ATR/FTIR experimental setup. The Al(OH)3spectra serve as reference spectral signatures. The spectra of corrosion samples from a simulated corrosion process have been collected and compared with the reference Al(OH)3 spectra. Also absorption spectra of naturally occurring corrosion collected from a fielded corroded aircraft part have been obtained and compared with the spectra from the simulated corrosion.

  14. Surface complexation of catechol to metal oxides: an ATR-FTIR, adsorption, and dissolution study.

    PubMed

    Gulley-Stahl, Heather; Hogan, Patrick A; Schmidt, Whitney L; Wall, Stephen J; Buhrlage, Andrew; Bullen, Heather A

    2010-06-01

    The interaction of catechol with chromium(III) oxide (Cr(2)O(3)), manganese dioxide (MnO(2)), iron(III) oxide (Fe(2)O(3)), and titanium dioxide (TiO(2)) was evaluated as a function of pH conditions (pH 3-10) and ionic strength using a combined approach of bulk adsorption, attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), and dissolution analysis. Adsorption of catechol showed a strong pH-dependent behavior with the metal oxides, remaining constant under acidic-neutral pH (3-7) and increasing under more basic conditions. In situ ATR-FTIR measurements indicate that catechol binds predominately as an outer-sphere complex on MnO(2) and as an inner-sphere complex on Fe(2)O(3), TiO(2), and Cr(2)O(3) substrates. Catechol complexation on Fe(2)O(3), TiO(2), and Cr(2)O(3) promotes dissolution at pH >5, whereas MnO(2) dissolution occurs under acidic and basic conditions (pH 3-10).

  15. Analysis of human bodily fluids on superabsorbent pads by ATR-FTIR.

    PubMed

    Gregório, Inês; Zapata, Félix; García-Ruiz, Carmen

    2017-01-01

    Superabsorbent pads are composed of different layers with different grades of absorbent capacity, being the lower one the most absorbent layer. Due to their complexity, the analysis of bodily fluids on superabsorbent pads is certainly difficult. In this study, semen, vaginal fluid and urine stains placed on superabsorbent pads including sanitary napkins, panty-liners and diapers were non-destructively detected by Attenuated Total Reflectance (ATR) Fourier Transform Infrared spectroscopy (FTIR). In spite of the higher absorbent capacity of the lower layers, this technique was able to detect the three fluids on the upper layer of all pads, showing that bodily fluids are distributed within all layers. Additionally, mixtures of these bodily fluids prepared on superabsorbent pads and cotton were studied, since real forensic investigations involving sexual abuse cases usually deal with mixtures of these fluids. Due to their IR marked protein region (1800-1480cm(-1)), semen and vaginal fluid were easily distinguished from urine. However, since semen and vaginal fluid have both a high protein composition, that region of their IR signatures were quite similar, except for slight visual differences, that should be further analysed. Therefore, we propose ATR-FTIR as a suitable, presumptive, non-destructive and rapid approach to detect stains of human bodily fluids on the upper layer of superabsorbent pads from sexual crimes. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Control of HIPK2 stability by ubiquitin ligase Siah-1 and checkpoint kinases ATM and ATR.

    PubMed

    Winter, Melanie; Sombroek, Dirk; Dauth, Ilka; Moehlenbrink, Jutta; Scheuermann, Karin; Crone, Johanna; Hofmann, Thomas G

    2008-07-01

    The tumour suppressor HIPK2 is an important regulator of cell death induced by DNA damage, but how its activity is regulated remains largely unclear. Here we demonstrate that HIPK2 is an unstable protein that colocalizes and interacts with the E3 ubiquitin ligase Siah-1 in unstressed cells. Siah-1 knockdown increases HIPK2 stability and steady-state levels, whereas Siah-1 expression facilitates HIPK2 polyubiquitination, degradation and thereby inactivation. During recovery from sublethal DNA damage, HIPK2, which is stabilized on DNA damage, is degraded through a Siah-1-dependent, p53-controlled pathway. Downregulation of Siah-1 inhibits HIPK2 degradation and recovery from damage, driving the cells into apoptosis. We have also demonstrated that DNA damage triggers disruption of the HIPK2-Siah-1 complex, resulting in HIPK2 stabilization and activation. Disruption of the HIPK2-Siah-1 complex is mediated by the ATM/ATR pathway and involves ATM/ATR-dependent phosphorylation of Siah-1 at Ser 19. Our results provide a molecular framework for HIPK2 regulation in unstressed and damaged cells.

  17. Comparison of real and simulated SAR imagery of ships for use in ATR

    NASA Astrophysics Data System (ADS)

    Ødegaard, N.; Knapskog, A. O.; Cochin, C.; Delahaye, B.

    2010-04-01

    Collecting real data to build a database for Automatic Target Recognition (ATR) in SAR imagery can be an overwhelming task. Simulated SAR images of targets are desirable. To use simulations for ATR one has to make sure they are good enough for discriminating among the different classes. This paper investigates the similarities between SAR images of ships simulated using a phenomenological SAR simulation tool and real data of the same targets collected with PicoSAR and TerraSAR-X. The study has been completed by FFI using the DGA MOCEM LT software. MOCEM generates a SAR image from a CAD model based on the major scattering mechanisms of the target in a matter of minutes. Simulations of several ships are compared to real data. The results obtained are highly dependent on the imaging geometry, as well as the CAD model complexity and the materials chosen for the target. Using normalized cross correlation, the simulation from the correct class always has the highest correlation with the real one when the scatterers are spatially distributed in the image. In other geometries, when the scatterers are more concentrated, the results were not satisfying, and further testing using other materials, model complexities and comparison metrics is necessary.

  18. Focusing, imaging, and ATR for the Gotcha 2008 wide angle SAR collection

    NASA Astrophysics Data System (ADS)

    Gianelli, Christopher D.; Xu, Luzhou

    2013-05-01

    The following work discusses IAA's approach to tackling the wide angle, circular spotlight, synthetic aperture radar (SAR) problem from the 2008 Gotcha wide angle SAR data set, which is publicly released, with unlimited distribution. This data set comes with a MATLAB image formation routine and attendant graphical user inter- face (GUI). We begin by introducing a simple approach to focusing the collected phase history data that utilizes point targets (quadrahedral targets) present in the scene. Two SAR imaging algorithms are then presented, namely, the data-independent backprojection (BP) algorithm and the data-adaptive sparse learning via itera- tive minimization (SLIM) algorithm. These imaging approaches are compared using the 2008 Gotcha wide angle SAR data to perform both a clutter discrimination experiment, as well as an automatic target recognition (ATR) experiment. The ATR system is composed of a target pose and target center estimation preprocessing system, and includes a novel target feature for the final classification stage. Empirical results obtained by applying the focusing approach and imaging algorithms to the 2008 Gotcha wide angle SAR data set are presented and described. The results presented highlight the benefit of applying the SLIM algorithm over its data-independent counterpart, as well as the utility of the novel target feature.

  19. Prediction of mixed hardwood lignin and carbohydrate content using ATR-FTIR and FT-NIR.

    PubMed

    Zhou, Chengfeng; Jiang, Wei; Via, Brian K; Fasina, Oladiran; Han, Guangting

    2015-05-05

    This study used Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and Fourier transform near-infrared (FT-NIR) spectroscopy with principal component regression (PCR) and partial least squares regression (PLS) to build hardwood prediction models. Wet chemistry analysis coupled with high performance liquid chromatography (HPLC) was employed to obtain the chemical composition of these samples. Spectra loadings were studied to identify key wavenumber in the prediction of chemical composition. NIR-PLS and FTIR-PLS performed the best for extractives, lignin and xylose, whose residual predictive deviation (RPD) values were all over 3 and indicates the potential for either instrument to provide superior prediction models with NIR performing slightly better. During testing, it was found that more accurate determination of holocellulose content was possible when HPLC was used. Independent chemometric models, for FT-NIR and ATR-FTIR, identified similar functional groups responsible for the prediction of chemical composition and suggested that coupling the two techniques could strengthen interpretation and prediction.

  20. ATR-FTIR microscopy in mapping mode for the study of verdigris and its secondary products

    NASA Astrophysics Data System (ADS)

    Prati, S.; Bonacini, I.; Sciutto, G.; Genty-Vincent, A.; Cotte, M.; Eveno, M.; Menu, M.; Mazzeo, R.

    2016-01-01

    To study degradation processes occurring on painting materials, the use of high-resolution micro-analytical techniques is highly requested since it provides a detailed identification and localisation of both the original and deteriorated ingredients. Among the various pigments recently studied, the characterisation of verdigris has received a major interest. This pigment has not a unique chemical formula, but its composition depends on the recipe employed for its manufacturing. Moreover, verdigris paints are not stable and are subject to a colour change from blue-green to green, which occurs in the first few months after the application. In this paper, we focused our attention on the use of ATR-FTIR mapping as a useful method to identify verdigris secondary products and pathways. Several mock-ups and real samples have been analysed, and the correlation among the detected compounds and their spatial location, obtained by the application of ATR-FTIR microscopy in mapping mode, allowed formulating some hypotheses on the degradation pattern of verdigris, which may feed the discussion on the transformation and stability of this pigment. From an analytical point of view, we showed how FTIR mapping approaches may be extremely useful both for the identification of compounds in complex matrix in which single spectra may limit the exhaustive characterisations due to bands overlapping and for the study of degradation pathways by taking into consideration the relative distribution of degradation products.

  1. Structural investigation of biological material in aqueous environment by means of infrared-ATR spectroscopy.

    PubMed

    Hofer, P; Fringeli, U P

    1979-12-01

    Infrared attenuated total reflection (ATR) spectroscopy may be used to investigate biological material (e.g., membranes, proteins, erythrocytes etc.) under biological conditions provided that adhesion of the sample can be achieved in aqueous environment. Uncharged lipid multilayer model membranes can be attached by hydrophobic interaction when hydrophobic internal reflection plates (e.g., ZnSe, CdTe) are used. However, if an electric field is applied across the membrane, germanium reflection elements would be preferred because of their low electric resistance (approximately 50 omega cm). This material can also be used if cells or proteins are linked chemically to the ATR plate because of the hydrophilic surface which is similar to that of glass and, thus, enables chemical modification by silanization. It has turned out that good adhesion of uncharged and negatively charged model membranes to germanium plates is achieved when they are coated with a monomolecular layer of aminopropylsilane. There is some evidence that erythrocytes remain more stable when adsorbed to a polymerized aminosilane coating (organic silanization) rather than to the corresponding monolayer (aqueous silanization). Negatively charged germanium surfaces have been obtained by succinylation of the aminosilane coating. Furthermore it has been demonstrated that proteins can be bound to the aminosilane coating by means of carbodiimide. Immobilized acetylcholinesterase was still enzymatically active.

  2. ATR-FTIR measurements of albumin and fibrinogen adsorption: Inert versus calcium phosphate ceramics.

    PubMed

    Boix, Marcel; Eslava, Salvador; Costa Machado, Gil; Gosselin, Emmanuel; Ni, Na; Saiz, Eduardo; De Coninck, Joël

    2015-11-01

    Arthritis, bone fracture, bone tumors and other musculoskeletal diseases affect millions of people across the world. Nowadays, inert and bioactive ceramics are used as bone substitutes or for bone regeneration. Their bioactivity is very much dictated by the way proteins adsorb on their surface. In this work, we compared the adsorption of albumin and fibrinogen on inert and calcium phosphates ceramics (CaPs) using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to follow in situ protein adsorption on these materials. To this effect, we developed a sol-gel technique to control the surface chemistry of an ATR-FTIR detector. Hydroxyapatite adsorbed more albumin and β-tricalcium phosphate adsorbed more fibrinogen. Biphasic calcium phosphate presented the lowest adsorption among CaP for both proteins, illustrating the effect of surface heterogeneities. Inert ceramics adsorbed a lower amount of both proteins compared with bioactive ceramics. A significant change was observed in the conformation of the adsorbed protein versus the surface chemistry. Hydroxyapatite produced a larger loss of α-helix structure on albumin and biphasic calcium phosphate reduced β-sheet percentage on fibrinogen. Inert ceramics produced large α-helix loss on albumin and presented weak interaction with fibrinogen. Zirconia did not adsorb albumin and titanium dioxide promoted huge denaturalization of fibrinogen.

  3. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic analysis of regenerated bone

    NASA Astrophysics Data System (ADS)

    Benetti, Carolina; Kazarain, Sergei G.; Alves, Marco A. V.; Blay, Alberto; Correa, Luciana; Zezell, Denise M.

    2014-03-01

    The cutting of bone is routinely required in medical procedures, especially in dental applications. In such cases, bone regeneration and new bone quality can determine the success of the treatment. This study investigated the main spectral differences of undamaged and healed bone using the ATR-FTIR spectroscopy technique. Three rabbits were submitted to a surgical procedure; a small piece of bone (3x3 mm2) was removed from both sides of their jaws using a high speed drill. After 15 days, the rabbits were euthanized and the jaws were removed. A bone slice was cut from each side of the jaw containing regions of undamaged and newly formed bone, resulting in six samples which were polished for spectroscopic comparison. The samples were analyzed by FTIR spectroscopy using a diamond ATR accessory. Spectral characteristics were compared and particular attention was paid to the proportion of phosphate to amide I bands and the width of the phosphate band. The results show that the ratio of phosphate to amide I is smaller in new bone tissue than in the undamaged bone, indicating a higher organic content in the newly formed bone. The analysis of the width of the phosphate band suggests a crystallinity difference between both tissues, since the width was higher in the new bone than in the natural bone. These results suggest that the differences observed in bone aging processes by FTIR spectroscopic can be applied to the study of healing processes.

  4. New automated terrain and feature extraction approach for the Predator UAV TESAR ATR system

    NASA Astrophysics Data System (ADS)

    Rosario, Dalton S.

    1999-08-01

    This paper describes a technique recently developed for target detection and false alarm reduction for the Predator unmanned aerial vehicle (UAV) tactical endurance synthetic aperture radar (TESAR) automatic target recognition (ATR) system. The approach does not attempt to label various objects in the SAR image (i.e., buildings, trees, roads); instead, it finds target-like characteristics in the image and compares their statistical/spatial relationship to larger structures in the scene. To do this, the approach merges the output of multiple CFAR (constant false alarm ratio) surfaces through a sequence of mathematical morphology tests. The output is further tested by a 'smart' clustering procedure, which performs an object- size test. With the use of these CFAR surfaces, a methodical sequence of morphological tests will find and retain large structures in the scene and eliminate cues that fall within these structures. The presence of supporting shadow downrange from the sensor is also used to eliminate objects with heights not typical to those of targets. Finally, a fast procedure performs a size test on elongated streaks. This procedure allows long objects to be smartly clustered as a single object while ensuring target proximity scenarios have no performance degradation. Application of this false alarm mitigator/detector to the Predator's SAR ATR algorithm suite produced a stunning reduction of one order of magnitude in the number of cues yielded by its baseline detector. This performance was consistent in scenes having natural and/or cultural clutter.

  5. Broadband dielectric spectroscopic, calorimetric, and FTIR-ATR investigations of D-arabinose aqueous solutions.

    PubMed

    Singh, Lokendra P; Cerveny, Silvina; Alegría, Angel; Colmenero, Juan

    2011-12-23

    The dielectric relaxation behavior of D-arabinose aqueous solutions at different water concentrations is examined by broadband dielectric spectroscopy in the frequency range of 10(-2) -10(7) Hz and in the temperature range of 120-300 K. Differential scanning calorimetry is also performed to find the glass transition temperatures (T(g)). In addition, the same solutions are analyzed by Fourier transform infrared (FTIR) spectroscopy using the attenuated total reflectance (ATR) method at the same temperature interval and in the frequency range of 3800-2800 cm(-1). The temperature dependence of the relaxation times is examined for the different weight fractions (x(w)) of water along with the temperature dependence of dielectric strength. Two relaxation processes are observed in the aqueous solutions for all concentrations of water. The slower process, the so-called primary relaxation process (process-I), is responsible for the T(g) whereas the faster one (designated as process-II) is due to the reorientational motion of the water molecules. As for other hydrophilic water solutions, dielectric data for process-II indicate the existence of a critical water concentration above which water mobility is less restricted. Accordingly, FTIR-ATR measurements on aqueous solutions show an increment in the intensity (area) of the O-H stretching sub-band close to 3200 cm(-1) as the water concentration increases. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Rapid profiling of Swiss cheese by attenuated total reflectance (ATR) infrared spectroscopy and descriptive sensory analysis.

    PubMed

    Kocaoglu-Vurma, N A; Eliardi, A; Drake, M A; Rodriguez-Saona, L E; Harper, W J

    2009-08-01

    The acceptability of cheese depends largely on the flavor formed during ripening. The flavor profiles of cheeses are complex and region- or manufacturer-specific which have made it challenging to understand the chemistry of flavor development and its correlation with sensory properties. Infrared spectroscopy is an attractive technology for the rapid, sensitive, and high-throughput analysis of foods, providing information related to its composition and conformation of food components from the spectra. Our objectives were to establish infrared spectral profiles to discriminate Swiss cheeses produced by different manufacturers in the United States and to develop predictive models for determination of sensory attributes based on infrared spectra. Fifteen samples from 3 Swiss cheese manufacturers were received and analyzed using attenuated total reflectance infrared spectroscopy (ATR-IR). The spectra were analyzed using soft independent modeling of class analogy (SIMCA) to build a classification model. The cheeses were profiled by a trained sensory panel using descriptive sensory analysis. The relationship between the descriptive sensory scores and ATR-IR spectra was assessed using partial least square regression (PLSR) analysis. SIMCA discriminated the Swiss cheeses based on manufacturer and production region. PLSR analysis generated prediction models with correlation coefficients of validation (rVal) between 0.69 and 0.96 with standard error of cross-validation (SECV) ranging from 0.04 to 0.29. Implementation of rapid infrared analysis by the Swiss cheese industry would help to streamline quality assurance.

  7. A novel role of the checkpoint kinase ATR in leptin signaling.

    PubMed

    Ericson, Elke; Wennberg Huldt, Charlotte; Strömstedt, Maria; Brodin, Peter

    2015-09-05

    In a world with increasing incidences of obesity, it becomes critical to understand the detailed regulation of appetite. To identify novel regulators of the signaling mediated by one of the key hormones of energy homeostasis, leptin, we screened a set of compounds for their effect on the downstream Signal Transducer and Activator of Transcription 3 (STAT3) signaling. Interestingly, cells exposed to inhibitors of the Ataxia Telangiectasia and RAD3-related protein ATR increased their leptin dependent STAT3 activity. This was due to failure of the cells to induce the negative feedback mediator Suppressor of Cytokine Signaling 3 (SOCS3), suggesting that ATR has a previously unknown role in the negative feedback regulation of leptin signaling. This is an important finding not only because it sheds light on additional genes involved in leptin signaling, but also because it brings forward a new potential therapeutic intervention point for increasing leptin signaling in obese individuals. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  8. In vivo interstitial glucose characterization and monitoring in the skin by ATR-FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Skrebova Eikje, Natalja

    2011-03-01

    Successful development of real-time non-invasive glucose monitoring would represent a major advancement not only in the treatment and management of patients with diabetes mellitus and carbohydrate metabolism disorders, but also for understanding in those biochemical, metabolic and (patho-)physiological processes of glucose at the molecular level in vivo. Here, ATR-FTIR spectroscopy technique has been challenged not only for in vivo measurement of interstitial glucose levels, but also for their non-invasive molecular qualitative and quantitative comparative characterization in the skin tissue. The results, based on calculated mean values of determined 5 glucose-specific peaks in the glucose-related 1000-1160 cm-1 region, showed intra- and inter-subject differences in interstitial glucose activity levels with their changes at different times and doses of OGTT, while raising questions about the relationships between interstitial and blood glucose levels. In conclusion, the introduction of ATR-FTIR spectroscopy technique has opened up an access to the interstitial fluid space in the skin tissue for interstitial glucose characterization and monitoring in vivo. Though interstitial versus blood glucose monitoring has different characteristics, it can be argued that accurate and precise measurements of interstitial glucose levels may be more important clinically.

  9. ATR inhibition induces synthetic lethality and overcomes chemoresistance in TP53- or ATM-defective chronic lymphocytic leukemia cells.

    PubMed

    Kwok, Marwan; Davies, Nicholas; Agathanggelou, Angelo; Smith, Edward; Oldreive, Ceri; Petermann, Eva; Stewart, Grant; Brown, Jeff; Lau, Alan; Pratt, Guy; Parry, Helen; Taylor, Malcolm; Moss, Paul; Hillmen, Peter; Stankovic, Tatjana

    2016-02-04

    TP53 and ataxia telangiectasia mutated (ATM) defects are associated with genomic instability, clonal evolution, and chemoresistance in chronic lymphocytic leukemia (CLL). Currently, therapies capable of providing durable remissions in relapsed/refractory TP53- or ATM-defective CLL are lacking. Ataxia telangiectasia and Rad3-related (ATR) mediates response to replication stress, the absence of which leads to collapse of stalled replication forks into chromatid fragments that require resolution through the ATM/p53 pathway. Here, using AZD6738, a novel ATR kinase inhibitor, we investigated ATR inhibition as a synthetically lethal strategy to target CLL cells with TP53 or ATM defects. Irrespective of TP53 or ATM status, induction of CLL cell proliferation upregulated ATR protein, which then became activated in response to replication stress. In TP53- or ATM-defective CLL cells, inhibition of ATR signaling by AZD6738 led to an accumulation of unrepaired DNA damage, which was carried through into mitosis because of defective cell cycle checkpoints, resulting in cell death by mitotic catastrophe. Consequently, AZD6738 was selectively cytotoxic to both TP53- and ATM-defective CLL cell lines and primary cells. This was confirmed in vivo using primary xenograft models of TP53- or ATM-defective CLL, where treatment with AZD6738 resulted in decreased tumor load and reduction in the proportion of CLL cells with such defects. Moreover, AZD6738 sensitized TP53- or ATM-defective primary CLL cells to chemotherapy and ibrutinib. Our findings suggest that ATR is a promising therapeutic target for TP53- or ATM-defective CLL that warrants clinical investigation. © 2016 by The American Society of Hematology.

  10. ATR signaling cooperates with ATM in the mechanism of low dose hypersensitivity induced by carbon ion beam.

    PubMed

    Xue, Lian; Furusawa, Yoshiya; Yu, Dong

    2015-10-01

    Little work has been done on the mechanism of low dose hyper-radiosensitivity (HRS) and later appeared radioresistance (termed induced radioresistance (IRR)) after irradiation with medium and high linear energy transfer (LET) particles. The aim of this study was to find out whether ATR pathway is involved in the mechanism of HRS induced by high LET radiation. GM0639 cells and two ATM deficient/mutant cells, AT5BIVA and AT2KY were irradiated by carbon ion beam. Thymidine block technique was developed to enrich the G2-phase population. Radiation induced early G2/M checkpoint was quantitatively assess with dual-parameter flow cytometry by detecting the cells positive for phospho-histone H3. The involvement of ATR pathway in HRS/IRR response was detected with pretreatment of specific inhibitors prior to carbon ion beam. The link between the early G2/M checkpoint and HRS/IRR under carbon ion beam was first confirmed in GM0639 cells, through the enrichment of cell population in G2-phase or with Aurora kinase inhibitor that attenuates the transition from G2 to M phase. Interestingly, the early G2/M arrest could still be observed in ATM deficient/mutant cells with an effect of ATR signaling, which was discovered to function in an LET-dependent manner, even as low as 0.2Gy for carbon ion radiation. The involvement of ATR pathway in heavy particles induced HRS/IRR was determined with the specific ATR inhibitor in GM0639 cells, which affected the HRS/IRR occurrence similarly as ATM inhibitor. These data demonstrate that ATR pathway may cooperate with ATM in the mechanism of low dose hypersensitivity induced by carbon ion beam.

  11. Fabrication of Uranium Oxycarbide Kernels for HTR Fuel

    SciTech Connect

    Charles Barnes; CLay Richardson; Scott Nagley; John Hunn; Eric Shaber

    2010-10-01

    Babcock and Wilcox (B&W) has been producing high quality uranium oxycarbide (UCO) kernels for Advanced Gas Reactor (AGR) fuel tests at the Idaho National Laboratory. In 2005, 350-µm, 19.7% 235U-enriched UCO kernels were produced for the AGR-1 test fuel. Following coating of these kernels and forming the coated-particles into compacts, this fuel was irradiated in the Advanced Test Reactor (ATR) from December 2006 until November 2009. B&W produced 425-µm, 14% enriched UCO kernels in 2008, and these kernels were used to produce fuel for the AGR-2 experiment that was inserted in ATR in 2010. B&W also produced 500-µm, 9.6% enriched UO2 kernels for the AGR-2 experiments. Kernels of the same size and enrichment as AGR-1 were also produced for the AGR-3/4 experiment. In addition to fabricating enriched UCO and UO2 kernels, B&W has produced more than 100 kg of natural uranium UCO kernels which are being used in coating development tests. Successive lots of kernels have demonstrated consistent high quality and also allowed for fabrication process improvements. Improvements in kernel forming were made subsequent to AGR-1 kernel production. Following fabrication of AGR-2 kernels, incremental increases in sintering furnace charge size have been demonstrated. Recently small scale sintering tests using a small development furnace equipped with a residual gas analyzer (RGA) has increased understanding of how kernel sintering parameters affect sintered kernel properties. The steps taken to increase throughput and process knowledge have reduced kernel production costs. Studies have been performed of additional modifications toward the goal of increasing capacity of the current fabrication line to use for production of first core fuel for the Next Generation Nuclear Plant (NGNP) and providing a basis for the design of a full scale fuel fabrication facility.

  12. Structure-Based Drug Design of Novel Potent and Selective Tetrahydropyrazolo[1,5-a]pyrazines as ATR Inhibitors

    PubMed Central

    2014-01-01

    A saturation strategy focused on improving the selectivity and physicochemical properties of ATR inhibitor HTS hit 1 led to a novel series of highly potent and selective tetrahydropyrazolo[1,5-a]pyrazines. Use of PI3Kα mutants as ATR crystal structure surrogates was instrumental in providing cocrystal structures to guide the medicinal chemistry designs. Detailed DMPK studies involving cyanide and GSH as trapping agents during microsomal incubations, in addition to deuterium-labeled compounds as mechanistic probes uncovered the molecular basis for the observed CYP3A4 TDI in the series. PMID:25589927

  13. Fuel injector

    DOEpatents

    Lambeth, Malcolm David Dick

    2001-02-27

    A fuel injector comprises first and second housing parts, the first housing part being located within a bore or recess formed in the second housing part, the housing parts defining therebetween an inlet chamber, a delivery chamber axially spaced from the inlet chamber, and a filtration flow path interconnecting the inlet and delivery chambers to remove particulate contaminants from the flow of fuel therebetween.

  14. Future Fuels

    DTIC Science & Technology

    2006-04-01

    financing, push technology and help motivate the building of the necessary manufacturing and distribution infrastructure. Hybrid Electric Vehicles , Tether...conclusions in three major areas: Hybrid Electric Vehicles (HEVs), fuel management during combat operations and manufactured fuels to address the...payoffs in the relatively near term, are: • Hybrid Electric Vehicles : The development of and commitment to hybrid electric architecture for TWVs

  15. 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.

  16. Improving the AGR Fuel Testing Power Density Profile Versus Irradiation-Time in the Advanced Test Reactor

    SciTech Connect

    Gray S. Chang; David A. Petti; John T. Maki; Misti A. Lillo

    2009-05-01

    The Very High Temperature gas-cooled Reactor (VHTR), which is currently being developed, achieves simplification of safety through reliance on ceramic-coated fuel particles. Each TRISO-coated fuel particle has its own containment which serves as the principal barrier against radionuclide release under normal operating and accident conditions. These fuel particles, in the form of graphite fuel compacts, are currently undergoing a series of irradiation tests in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) to support the Advanced Gas-Cooled Reactor (AGR) fuel qualification program. A representive coated fuel particle with an 235U enrichment of 19.8 wt% was used in this analysis. The fuel burnup analysis tool used to perform the neutronics study reported herein, couples the Monte Carlo transport code MCNP, with the radioactive decay and burnup code ORIGEN2. The fuel burnup methodology known as Monte-Carlo with ORIGEN2 (MCWO) was used to evaluate the AGR experiment assembly and demonstrate compliance with ATR safety requirements. For the AGR graphite fuel compacts, the MCWO-calculated fission power density (FPD) due to neutron fission in 235U is an important design parameter. One of the more important AGR fuel testing requirements is to maintain the peak fuel compact temperature close to 1250°C throughout the proposed irradiation campaign of 550 effective full power days (EFPDs). Based on the MCWO-calculated FPD, a fixed gas gap size was designed to allow regulation of the fuel compact temperatures throughout the entire fuel irradiation campaign by filling the gap with a mixture of helium and neon gases. The chosen fixed gas gap can only regulate the peak fuel compact temperature in the desired range during the irradiation test if the ratio of the peak power density to the time-dependent low power density (P/T) at 550 EFPDs is less than 2.5. However, given the near constant neutron flux within the ATR driver core and the depletion of 235U in

  17. Selected Can-Do Statements and Learning Materials for ATR CALL BRIX: Helping University Students in Japan Improve Their TOEIC Scores

    ERIC Educational Resources Information Center

    Ishikawa, Yasushige; Kondo, Mutsumi; Akahane-Yamada, Reiko; Smith, Craig; Hatakeda, Hiroshi; Wada, Norihisa

    2012-01-01

    This paper reports on the use of can-do statements (CDS) for the development of learning materials to prepare Japanese university students for the Test of English for International Communication (TOEIC). These learning materials have been made available on ATR CALL BRIX (http://www.atr-lt.jp/products/brix/index.html), a wwwbased courseware with a…

  18. A synthetic lethal screen reveals enhanced sensitivity to ATR inhibitor treatment in mantle cell lymphoma with ATM loss-of-function.

    PubMed

    Menezes, Daniel L; Holt, Jenny; Tang, Yan; Feng, Jiajia; Barsanti, Paul; Pan, Yue; Ghoddusi, Majid; Zhang, Wei; Thomas, George; Holash, Jocelyn; Lees, Emma; Taricani, Lorena

    2015-01-01

    Mechanisms to maintain genomic integrity are essential for cells to remain viable. Not surprisingly, disruption of key DNA damage response pathway factors, such as ataxia telangiectasia-mutated (ATM)/ataxia telangiectasia and RAD3-related (ATR) results in loss of genomic integrity. Here, a synthetic lethal siRNA-screening approach not only confirmed ATM but identified additional replication checkpoint proteins, when ablated, enhanced ATR inhibitor (ATRi) response in a high-content γ-H2AX assay. Cancers with inactivating ATM mutations exhibit impaired DNA double-stranded break (DSB) repair and rely on compensatory repair pathways for survival. Therefore, impairing ATR activity may selectively sensitize cancer cells to killing. ATR inhibition in an ATM-deficient context results in phosphorylation of DNA-dependent protein kinase catalytic subunits (DNA-PKcs) and leads to induction of γ-H2AX. Using both in vitro and in vivo models, ATR inhibition enhanced efficacy in ATM loss-of-function mantle cell lymphoma (MCL) compared with ATM wild-type cancer cells. In summary, single-agent ATR inhibitors have therapeutic utility in the treatment of cancers, like MCL, in which ATM function has been lost. These data suggest that single-agent ATR inhibitors have therapeutic utility and that ATR uses a complex and coordinated set of proteins to maintain genomic stability that could be further exploited. ©2014 American Association for Cancer Research.

  19. Fuel cell-fuel cell hybrid system

    DOEpatents

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  20. In situ ATR-FTIR and surface complexation modeling studies on the adsorption of dimethylarsinic acid and p-arsanilic acid on iron-(oxyhydr)oxides.

    PubMed

    Mitchell, William; Goldberg, Sabine; Al-Abadleh, Hind A

    2011-06-15

    Arsenic is an element that exists naturally in many rocks and minerals around the world. It also accumulates in petroleum, shale, oil sands, and coal deposits as a result of biogeochemical processes, and it has been found in fly ash from the combustion of solid biofuels. Arsenic compounds in their organic and inorganic forms pose both a health and an environmental risk, and continue to be a challenge to the energy industry. The environmental fate and removal technologies of arsenic compounds are controlled to a large extent by their surface interactions with inorganic and organic adsorbents. We report thermodynamic binding constants, K(binding), from applying the triple-layer surface complexation model to adsorption isotherm and pH envelope data for dimethylarsinic acid (DMA) and p-arsanilic acid (p-AsA) on hematite and goethite. Ligand exchange reactions were constructed based on the interpretation of ATR-FTIR spectra of DMA and p-AsA surface complexes. Surface coverage of adsorbates was quantified in situ from the spectral component at 840 cm(-1). The best fit to the DMA adsorption data was obtained using outer-sphere complex formation, whereas for p-AsA, the best fit was obtained using two monodentate inner-sphere surface complexes. The significance of the results is discussed in relation to improving modeling tools used by environmental regulators and the energy sector for optimum control of arsenic content in fuels.

  1. Original Experimental Approach for Assessing Transport Fuel Stability.

    PubMed

    Bacha, Kenza; Ben Amara, Arij; Alves Fortunato, Maira; Wund, Perrine; Veyrat, Benjamin; Hayrault, Pascal; Vannier, Axel; Nardin, Michel; Starck, Laurie

    2016-10-21

    The study of fuel oxidation stability is an important issue for the development of future fuels. Diesel and kerosene fuel systems have undergone several technological changes to fulfill environmental and economic requirements. These developments have resulted in increasingly severe operating conditions whose suitability for conventional and alternative fuels needs to be addressed. For example, fatty acid methyl esters (FAMEs) introduced as biodiesel are more prone to oxidation and may lead to deposit formation. Although several methods exist to evaluate fuel stability (induction period, peroxides, acids, and insolubles), no technique allows one to monitor the real-time oxidation mechanism and to measure the formation of oxidation intermediates that may lead to deposit formation. In this article, we developed an advanced oxidation procedure (AOP) based on two existing reactors. This procedure allows the simulation of different oxidation conditions and the monitoring of the oxidation progress by the means of macroscopic parameters, such as total acid number (TAN) and advanced analytical methods like gas chromatography coupled to mass spectrometry (GC-MS) and Fourier Transform Infrared - Attenuated Total Reflection (FTIR-ATR). We successfully applied AOP to gain an in-depth understanding of the oxidation kinetics of a model molecule (methyl oleate) and commercial diesel and biodiesel fuels. These developments represent a key strategy for fuel quality monitoring during logistics and on-board utilization.

  2. Original Experimental Approach for Assessing Transport Fuel Stability

    PubMed Central

    Bacha, Kenza; Ben Amara, Arij; Alves Fortunato, Maira; Wund, Perrine; Veyrat, Benjamin; Hayrault, Pascal; Vannier, Axel; Nardin, Michel; Starck, Laurie

    2016-01-01

    The study of fuel oxidation stability is an important issue for the development of future fuels. Diesel and kerosene fuel systems have undergone several technological changes to fulfill environmental and economic requirements. These developments have resulted in increasingly severe operating conditions whose suitability for conventional and alternative fuels needs to be addressed. For example, fatty acid methyl esters (FAMEs) introduced as biodiesel are more prone to oxidation and may lead to deposit formation. Although several methods exist to evaluate fuel stability (induction period, peroxides, acids, and insolubles), no technique allows one to monitor the real-time oxidation mechanism and to measure the formation of oxidation intermediates that may lead to deposit formation. In this article, we developed an advanced oxidation procedure (AOP) based on two existing reactors. This procedure allows the simulation of different oxidation conditions and the monitoring of the oxidation progress by the means of macroscopic parameters, such as total acid number (TAN) and advanced analytical methods like gas chromatography coupled to mass spectrometry (GC-MS) and Fourier Transform Infrared - Attenuated Total Reflection (FTIR-ATR). We successfully applied AOP to gain an in-depth understanding of the oxidation kinetics of a model molecule (methyl oleate) and commercial diesel and biodiesel fuels. These developments represent a key strategy for fuel quality monitoring during logistics and on-board utilization. PMID:27805606

  3. Fuels research: Fuel thermal stability overview

    NASA Technical Reports Server (NTRS)

    Cohen, S. M.

    1980-01-01

    Alternative fuels or crude supplies are examined with respect to satisfying aviation fuel needs for the next 50 years. The thermal stability of potential future fuels is discussed and the effects of these characteristics on aircraft fuel systems are examined. Advanced fuel system technology and design guidelines for future fuels with lower thermal stability are reported.

  4. Identification and classification of textile fibres using ATR-FT-IR spectroscopy with chemometric methods

    NASA Astrophysics Data System (ADS)

    Peets, Pilleriin; Leito, Ivo; Pelt, Jaan; Vahur, Signe

    2017-02-01

    The possibility of classification of single- and two-component textile materials using ATR-FT-IR spectra and chemometric methods, principal component analysis (PCA) and discriminant analysis, was assessed. Altogether 89 textile samples belonging to 26 different types (11 one- and 15 two-component textiles) were investigated. It was found that PCA classification using only two or three principal components (PCs) enables identifying different one- and two-component textiles, although with two important limitations: it was not always possible to distinguish between the cellulose-based fibres (cotton, linen and in some cases viscose) and it was only partly possible to distinguish between silk and wool. The statistical discriminant analysis can use as many PCs as there are sample classes and due to that can discriminate between single-component fibres, including viscose from linen and cotton as well as silk from wool. Besides that, in both of these cases, involving optical microscopy as an additional technique enabled unequivocal identification of the fibres. The possibilities of semi-quantitative analysis of mixed fibres (cotton-polyester, wool-polyester and wool-polyamide) with PCA were investigated and it was found that approximate quantitative composition is obtainable if for the mixed fibre sample a number of spectra are averaged in order to minimize the effect of structural inhomogeneity. For approximate content determination 25 spectra of selected two-component samples were registered for calibration and the averaged spectrum for each sample was computed. Due to the structural inhomogeneity of mixed textiles, obtaining accurate quantitative composition from real samples is not possible with ATR-FT-IR. The main problems with ATR-FT-IR-PCA classification are (1) difficulties in getting high quality spectra from some textiles (e.g. polyacrylic), (2) inhomogeneity of the textile fibres in the case of two-component fibres and (3) intrinsic similarity between the

  5. Identification and classification of textile fibres using ATR-FT-IR spectroscopy with chemometric methods.

    PubMed

    Peets, Pilleriin; Leito, Ivo; Pelt, Jaan; Vahur, Signe

    2017-02-15

    The possibility of classification of single- and two-component textile materials using ATR-FT-IR spectra and chemometric methods, principal component analysis (PCA) and discriminant analysis, was assessed. Altogether 89 textile samples belonging to 26 different types (11 one- and 15 two-component textiles) were investigated. It was found that PCA classification using only two or three principal components (PCs) enables identifying different one- and two-component textiles, although with two important limitations: it was not always possible to distinguish between the cellulose-based fibres (cotton, linen and in some cases viscose) and it was only partly possible to distinguish between silk and wool. The statistical discriminant analysis can use as many PCs as there are sample classes and due to that can discriminate between single-component fibres, including viscose from linen and cotton as well as silk from wool. Besides that, in both of these cases, involving optical microscopy as an additional technique enabled unequivocal identification of the fibres. The possibilities of semi-quantitative analysis of mixed fibres (cotton-polyester, wool-polyester and wool-polyamide) with PCA were investigated and it was found that approximate quantitative composition is obtainable if for the mixed fibre sample a number of spectra are averaged in order to minimize the effect of structural inhomogeneity. For approximate content determination 25 spectra of selected two-component samples were registered for calibration and the averaged spectrum for each sample was computed. Due to the structural inhomogeneity of mixed textiles, obtaining accurate quantitative composition from real samples is not possible with ATR-FT-IR. The main problems with ATR-FT-IR-PCA classification are (1) difficulties in getting high quality spectra from some textiles (e.g. polyacrylic), (2) inhomogeneity of the textile fibres in the case of two-component fibres and (3) intrinsic similarity between the

  6. A Kinase-Independent Role for the Rad3ATR-Rad26ATRIP Complex in Recruitment of Tel1ATM to Telomeres in Fission Yeast

    PubMed Central

    Subramanian, Lakxmi; Nakamura, Toru M.

    2010-01-01

    ATM and ATR are two redundant checkpoint kinases essential for the stable maintenance of telomeres in eukaryotes. Previous studies have established that MRN (Mre11-Rad50-Nbs1) and ATRIP (ATR Interacting Protein) interact with ATM and ATR, respectively, and recruit their partner kinases to sites of DNA damage. Here, we investigated how Tel1ATM and Rad3ATR recruitment to telomeres is regulated in fission yeast. Quantitative chromatin immunoprecipitation (ChIP) assays unexpectedly revealed that the MRN complex could also contribute to the recruitment of Tel1ATM to telomeres independently of the previously established Nbs1 C-terminal Tel1ATM interaction domain. Recruitment of Tel1ATM to telomeres in nbs1-c60Δ cells, which lack the C-terminal 60 amino acid Tel1ATM interaction domain of Nbs1, was dependent on Rad3ATR-Rad26ATRIP, but the kinase domain of Rad3ATR was dispensable. Thus, our results establish that the Rad3ATR-Rad26ATRIP complex contributes to the recruitment of Tel1ATM independently of Rad3ATR kinase activity, by a mechanism redundant with the Tel1ATM interaction domain of Nbs1. Furthermore, we found that the N-terminus of Nbs1 contributes to the recruitment of Rad3ATR-Rad26ATRIP to telomeres. In response to replication stress, mammalian ATR–ATRIP also contributes to ATM activation by a mechanism that is dependent on the MRN complex but independent of the C-terminal ATM interaction domain of Nbs1. Since telomere protection and DNA damage response mechanisms are very well conserved between fission yeast and mammalian cells, mammalian ATR–ATRIP may also contribute to the recruitment of ATM to telomeres and to sites of DNA damage independently of ATR kinase activity. PMID:20140190

  7. FUEL ELEMENT

    DOEpatents

    Bean, R.W.

    1963-11-19

    A ceramic fuel element for a nuclear reactor that has improved structural stability as well as improved cooling and fission product retention characteristics is presented. The fuel element includes a plurality of stacked hollow ceramic moderator blocks arranged along a tubular raetallic shroud that encloses a series of axially apertured moderator cylinders spaced inwardly of the shroud. A plurality of ceramic nuclear fuel rods are arranged in the annular space between the shroud and cylinders of moderator and appropriate support means and means for directing gas coolant through the annular space are also provided. (AEC)

  8. Fuel ethanol

    SciTech Connect

    Not Available

    1989-02-01

    This report discusses the Omnibus Trade and Competitiveness Act of 1988 which requires GAO to examine fuel ethanol imports from Central America and the Caribbean and their impact on the U.S. fuel ethanol industry. Ethanol is the alcohol in beverages, such as beer, wine, and whiskey. It can also be used as a fuel by blending with gasoline. It can be made from renewable resources, such as corn, wheat, grapes, and sugarcane, through a process of fermentation. This report finds that, given current sugar and gasoline prices, it is not economically feasible for Caribbean ethanol producers to meet the current local feedstock requirement.

  9. Minimum criticality dose evaluation for the Irradiated Fuel Storage Facility

    SciTech Connect

    Kim, S.S.

    1999-09-01

    The Irradiated Fuel Storage Facility (IFSF) is a government-owned, contractor-operated facility located at the Idaho National Engineering and Environmental Laboratory within the Idaho Nuclear Technology and Engineering Center. The mission of the facility is to provide safe dry storage for various types of irradiated fuels. Included are fuel elements such as irradiated ATR, EBR, MTR, Fort St. Vrain, TRIGA, and ROVER Parka fuels. Fuels requiring dry storage are received at the IFSF in fuel-shipping casks. At the facility receiving dock, the casks are removed from the transport vehicle, positioned in a cask transport car, and moved into the fuel-handling cave. Several functions are performed in the fuel-handling cave, including transferring fuel from shipping casks to storage canisters, preparing fuel elements for storage and processing. The minimum postulated criticality dose calculations were performed for the cask-receiving and fuel-handling areas to place criticality alarm system (CAS) detectors. The number of fissions for the minimum accident of concern is based on a dose of 20-rad air at 2 m in 1 min. The eigenvalue calculations were first performed to determine the size of the critical source. Then, two sets of fixed-source calculations were followed to calculate contributions from neutron and capture gamma rays and from prompt gamma rays. Two sets of MCNP calculations involved point and spherical critical sources. Validity of the Monte Carlo results was tested against ANISN deterministic calculations. The flux-to-dose conversion factors are based on ANSI/ANS-6.1.1-1977. All of the MCNP runs used continuous-energy ENDF/B-V cross sections. The BUGLE-80 cross-section library was used for the ANISN calculations.

  10. Advanced Fuel Cycle Initiative - Projected Linear Heat Generation Rate and Burnup Calculations

    SciTech Connect

    Richard G. Ambrosek; Gray S. Chang; Debbie J. Utterbeck

    2005-02-01

    This report provides documentation of the physics analysis performed to determine the linear heat generation rate (LHGR) and burnup calculations for the Advanced Fuel Cycle Initiative (AFCI) tests, AFC-1D, AFC-1H, and AFC-1G. The AFC-1D and AFC-1H tests consists of low-fertile metallic fuel compositions and the AFC-1G test consists of non-fertile and low-fertile nitride compositions. These tests will be irradiated in the East Flux Trap (EFT) positions E1, E2, and E3, respectively, during Advanced Test Reactor (ATR) Cycle 135B.

  11. Bleomycin-induced over-replication involves sustained inhibition of mitotic entry through the ATM/ATR pathway.

    PubMed

    Nakayama, Yuji; Igarashi, Asae; Kikuchi, Ikue; Obata, Yuuki; Fukumoto, Yasunori; Yamaguchi, Naoto

    2009-09-10

    Polyploid cells result in aneuploidy through aberrant chromosome segregation, possibly leading to tumorigenesis. Although polyploid cells are induced through over-replication by a variety of agents, including DNA-damaging drugs, the mechanisms that induce polyploidy have been hitherto unknown. Here, we show that treatment with bleomycin, a glycopeptide anticancer drug, induces over-replication at low cytotoxic doses. During bleomycin-induced over-replication, mitotic entry is inhibited through tyrosine phosphorylation of CDK1 along the ATM/ATR pathway in the early phase of treatment. Bleomycin-induced over-replication is inhibited by the inhibitors of the ATM/ATR pathway through abrogation of bleomycin-induced G2 arrest, and the ATM/ATR inhibitors promote cell death instead of over-replication. Following the phosphorylation of CDK1, the level of cyclin B1 is decreased in the late phase of treatment. Time-lapse imaging of clone cells that express a live cell marker of endogenous cyclin B1 revealed that cyclin B1 is degraded in G2-arrested cells upon bleomycin treatment. Our findings lead to a model of how the ATM/ATR pathway acts as a molecular switch for regulating cell fates, flipping between cell death via progress into mitosis, and over-replication via sustained G2 arrest upon DNA damage, where cyclin B1 degradation is an important factor for inducing over-replication.

  12. Inactivation of ATM/ATR DNA Damage Checkpoint Promotes Androgen Induced Chromosomal Instability in Prostate Epithelial Cells

    PubMed Central

    Chiu, Yung-Tuen; Liu, Ji; Tang, Kaidun; Wong, Yong-Chuan; Khanna, Kum Kum; Ling, Ming-Tat

    2012-01-01

    The ATM/ATR DNA damage checkpoint functions in the maintenance of genetic stability and some missense variants of the ATM gene have been shown to confer a moderate increased risk of prostate cancer. However, whether inactivation of this checkpoint contributes directly to prostate specific cancer predisposition is still unknown. Here, we show that exposure of non-malignant prostate epithelial cells (HPr-1AR) to androgen led to activation of the ATM/ATR DNA damage response and induction of cellular senescence. Notably, knockdown of the ATM gene expression in HPr-1AR cells can promote androgen-induced TMPRSS2: ERG rearrangement, a prostate-specific chromosome translocation frequently found in prostate cancer cells. Intriguingly, unlike the non-malignant prostate epithelial cells, the ATM/ATR DNA damage checkpoint appears to be defective in prostate cancer cells, since androgen treatment only induced a partial activation of the DNA damage response. This mechanism appears to preserve androgen induced autophosphorylation of ATM and phosphorylation of H2AX, lesion processing and repair pathway yet restrain ATM/CHK1/CHK2 and p53 signaling pathway. Our findings demonstrate that ATM/ATR inactivation is a crucial step in promoting androgen-induced genomic instability and prostate carcinogenesis. PMID:23272087

  13. Characterization of southern yellow pine bark layers by Attenuated Total Reflectance (ATR) and Fourier Transform Infrared (FT-IR) Spectroscopy

    Treesearch

    Thomas L. Eberhardt

    2009-01-01

    The outer bark (rhytidome) of the southern yellow pines is a complex structure comprised of alternating layers of obliterated phloem and periderm tissues, with the latter comprised of three layers, those being phellem, phellogen, and phelloderm. An attenuated total reflectance (ATR) sampling accessory, coupled with a Fourier transform infrared (FTIR) spectrometer,...

  14. Stability of indomethacin with relevance to the release from amorphous solid dispersions studied with ATR-FTIR spectroscopic imaging.

    PubMed

    Ewing, Andrew V; Clarke, Graham S; Kazarian, Sergei G

    2014-08-18

    This work presents the use of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and spectroscopic imaging to study the stability and dissolution behaviour of amorphous solid dispersions (ASDs). ASDs are employed to improve the bioavailability of drugs which are poorly soluble in aqueous solutions. Selecting the appropriate polymeric excipients for use in pharmaceutical tablets is crucial to control drug stability and subsequent release. In this study, indomethacin was used as a model poorly-aqueous soluble drug since the amorphous-form has improved dissolution properties over its crystalline forms. ASDs of indomethacin/polyethylene glycol (PEG) and indomethacin/hydroxypropyl methylcellulose (HPMC) in a 1:3 wt ratio were compared. Firstly, ATR-FTIR spectroscopy was employed to monitor the stability of indomethacin in the ASDs over 96 h. While the indomethacin/HPMC ASD showed the ability to maintain the amorphous indomethacin form for longer periods of time, ATR-FTIR spectra revealed that indomethacin in the drug/PEG ASD crystallised to the stable γ-form, via the α-form. Secondly, ATR-FTIR spectroscopic imaging was used to study the dissolution of ASD tablets in a phosphate buffer (pH 7.5). Crystallisation of amorphous indomethacin was characterised in the spectra collected during the dissolution of the indomethacin/PEG ASD which consequently hindered release into the surrounding solution. In contrast, release of amorphous indomethacin was more effective from HPMC.

  15. Activation of ATR-Chk1 pathway facilitates EBV-mediated transformation of primary tonsillar B-cells

    PubMed Central

    Mordasini, Vanessa; Ueda, Seigo; Aslandogmus, Roberta; Berger, Christoph; Gysin, Claudine; Hühn, Daniela; Sartori, Alessandro A

    2017-01-01

    Primary infection of the immunocompromised host with the oncovirus Epstein-Barr virus (EBV) that targets mainly B-cells is associated with an increased risk for EBV-associated tumors. The early events subsequent to primary infection with potential for B-cell transformation are poorly studied. Here, we modeled in vitro the primary infection by using B-cells isolated from tonsils, the portal of entry of EBV, since species specificity of EBV hampers modeling in experimental animals. Increasing evidence indicates that the host DNA damage response (DDR) can influence and be influenced by EBV infection. Thus, we inoculated tonsillar B-cells (TBCs) with EBV-B95.8 and investigated cell proliferation and the DDR during the first 96 hours thereafter. We identified for the first time that EBV infection of TBCs induces a period of hyperproliferation 48-96 hours post infection characterized by the activation of ataxia telangiectasia and Rad3-releated (ATR) and checkpoint kinase-1 (Chk1). Whereas inhibition of Chk1 did not affect B-cell transformation, the specific inhibition of ATR robustly decreased the transformation efficiency of EBV. Our results suggest that activation of ATR is key for EBV-induced B-cell transformation. Thus, targeting the interaction between ATR/Chk1 and EBV could offer new options for the treatment of EBV-associated malignancies. PMID:28031537

  16. Photoinduced Graft-Polymerization of Acrylic Acid on Polyethylene and Polypropylene Surfaces: Comparative Study Using IR-ATR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Gorbachev, A. A.; Tretinnikov, O. N.; Shkrabatovskaya, L. V.; Prikhodchenko, L. K.

    2014-11-01

    Photoinduced graft-polymerization of acrylic acid on the surface of polyethylene and polypropylene films containing a photoinitiator pre-adsorbed from a thin layer of non-de-aerated aqueous monomer solution was investigated. Data about the monomer conversion and grafting depth as functions of the UV irradiation time and polymer nature were obtained using IR-ATR spectroscopy.

  17. Rapid determination of baicalin and total baicalein content in Scutellariae radix by ATR-IR and NIR spectroscopy.

    PubMed

    Navarro Escamilla, M; Rodenas Sanz, F; Li, H; Schönbichler, S A; Yang, B; Bonn, G K; Huck, C W

    2013-09-30

    In this study methods for the quantification of baicalin and total baicalein in Scutellariae radix with near infrared (NIR) spectroscopy and attenuated-total-reflectance mid-infrared (ATR-IR) spectroscopy in hyphenation with multivariate analysis were developed and compared. The reference analysis was performed by high performance liquid chromatography coupled to diode array detection (HPLC-DAD). Different pretreatments like standard normal variate (SNV), multiplicative scatter correction (MSC), first and second derivative Savitzky-Golay were applied on the spectra to optimize the calibrations. A principal component analysis was performed with both spectroscopic methods to distinguish wild and cultivated samples. Quality parameters obtained for test-set calibration models of ATR-IR spectroscopy (baicalin: standard error of prediction (SEP)=1.31, ratio performance to deviation (RPD)=2.91 and R(2)=0.88; total baicalein: SEP=1.02, RPD=3.24 and R(2)=0.89) and NIR spectroscopy (baicalin: SEP=1.50, RPD=2.54 and R(2)=0.88; total baicalein: SEP=1.19, RPD=2.76 and R(2)=0.84) demonstrate that both spectroscopic techniques in combination with multivariate analysis are successful tools for the quantification of baicalin and total baicalein in Scutellariae radix, but it was found that ATR-IR spectroscopy provides higher accuracy in the given application. Furthermore it was proved that wild and cultivated samples can be distinguished by ATR-IR.

  18. Measured thermal and fast neutron fluence rates for ATF-1 holders during ATR cycle 158B/159A

    SciTech Connect

    Smith, Larry Don; Miller, David Torbet; Walker, Billy Justin

    2016-11-01

    This report contains the thermal (2200 m/s) and fast (E>1MeV) neutron fluence rate data for the ATF-1 holders located in core for ATR Cycle 158B/159A which were measured by the Radiation Measurements Laboratory (RML).

  19. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) in the discrimination of normal and oral cancer blood plasma

    NASA Astrophysics Data System (ADS)

    Pachaiappan, Rekha; Prakasarao, Aruna; Singaravelu, Ganesan

    2017-02-01

    Oral cancer is the most frequent type of cancer that occurs with 75000 to 80000 new cases reported every year in India. The carcinogens from tobacco and related products are the main cause for the oral cancer. ATR-FTIR method is label free, fast and cost-effective diagnostic method would allow for rapid diagnostic results in earlier stages by the minimal chemical changes occur in the biological metabolites available in the blood plasma. The present study reports the use of ATR-FTIR data with advanced statistical model (LDA-ANN) in the diagnosis of oral cancer from normal with better accuracy. The infrared spectra were acquired on ATR-FTIR Jasco spectrophotometer at 4 cm-1 resolution, 30 scans, in the 1800-900 cm-1 spectral range. Each sample had 5 spectra recorded from each blood plasma sample. The spectral data were routed through the multilayer perception of artificial neural network to evaluate for the statistical efficacy. Among the spectral data it was found that amide II (1486 cm-1) and lipid (1526 cm-1) affords about 90 % in the discrimination between groups using LDA. These preliminary results indicate that ATR-FTIR is useful to differentiate normal subject from oral cancer patients using blood plasma.

  20. FTIR-ATR-based prediction and modelling of lignin and energy contents reveals independent intra-specific variation of these traits in bioenergy poplars

    PubMed Central

    2011-01-01

    Background There is an increasing demand for renewable resources to replace fossil fuels. However, different applications such as the production of secondary biofuels or combustion for energy production require different wood properties. Therefore, high-throughput methods are needed for rapid screening of wood in large scale samples, e.g., to evaluate the outcome of tree breeding or genetic engineering. In this study, we investigated the intra-specific variability of lignin and energy contents in extractive-free wood of hybrid poplar progenies (Populus trichocarpa × deltoides) and tested if the range was sufficient for the development of quantitative prediction models based on Fourier transform infrared spectroscopy (FTIR). Since lignin is a major energy-bearing compound, we expected that the energy content of wood would be positively correlated with the lignin content. Results Lignin contents of extractive-free poplar wood samples determined by the acetyl bromide method ranged from 23.4% to 32.1%, and the calorific values measured with a combustion calorimeter varied from 17260 to 19767 J g-1. For the development of calibration models partial least square regression and cross validation was applied to correlate FTIR spectra determined with an attenuated total reflectance (ATR) unit to measured values of lignin or energy contents. The best models with high coefficients of determination (R2 (calibration) = 0.91 and 0.90; R2 (cross-validation) = 0.81 and 0.79) and low root mean square errors of cross validation (RMSECV = 0.77% and 62 J g-1) for lignin and energy determination, respectively, were obtained after data pre-processing and automatic wavenumber restriction. The calibration models were validated by analyses of independent sets of wood samples yielding R2 = 0.88 and 0.86 for lignin and energy contents, respectively. Conclusions These results show that FTIR-ATR spectroscopy is suitable as a high-throughput method for lignin and energy estimations in large

  1. Potential effects of gallium on cladding materials

    SciTech Connect

    Wilson, D.F.; Beahm, E.C.; Besmann, T.M.; DeVan, J.H.; DiStefano, J.R.; Gat, U.; Greene, S.R.; Rittenhouse, P.L.; Worley, B.A.

    1997-10-01

    This paper identifies and examines issues concerning the incorporation of gallium in weapons derived plutonium in light water reactor (LWR) MOX fuels. Particular attention is given to the more likely effects of the gallium on the behavior of the cladding material. The chemistry of weapons grade (WG) MOX, including possible consequences of gallium within plutonium agglomerates, was assessed. Based on the calculated oxidation potentials of MOX fuel, the effect that gallium may have on reactions involving fission products and possible impact on cladding performance were postulated. Gallium transport mechanisms are discussed. With an understanding of oxidation potentials and assumptions of mechanisms for gallium transport, possible effects of gallium on corrosion of cladding were evaluated. Potential and unresolved issues and suggested research and development (R and D) required to provide missing information are presented.

  2. Characterization of poly(L-lactide/Propylene glycol) based polyurethane films using ATR-FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Manap, Siti Munirah; Ahmad, Azizan; Anuar, Farah Hannan

    2016-11-01

    A polyurethane films consisting of PLLA, PPG and PLLA-PPG were prepared using solution casting method. Three types of polyurethane were prepared: PPLA:PMDI, PPG:PMDI and PLLA-PPG:PMDI in the presence of polymeric diphenylmethane diisocyanate (PMDI) as the coupling agent and catalyst, Sn(Oct)2. The aim of this research was to improve the physicals properties of PLLA and PPG homopolymers through copolymerization between the two polymers. The homopolymers and polyurethane films were characterized using ATR-FTIR spectroscopy. Chemical reaction between PLLA, PPG and PMDI before and after the reaction were confirmed by observing the shifting of wavenumber for the carbonyl and ether group. Other than that, the additional band for N-H after the reaction indicated that the reaction was successful.

  3. FTIR-ATR evaluation of topical skin protectants useful for sulfur mustard and related compounds

    NASA Astrophysics Data System (ADS)

    Braue, Ernest H., Jr.; Litchfield, Marty R.; Bangledorf, Catherine R.; Rieder, Robert G.

    1992-03-01

    The US Army has a need to develop topical protectants that can decrease the effects of cutaneous exposure to chemical warfare (CW) agents. Such materials would enhance a soldier's ability to carry out the mission in a chemically hostile environment, would lessen the burden on medical personnel, and may allow the casualties to return to duty in a shorter period of time than might otherwise be possible. In a preliminary report (E. H. Braue, Jr. and M. G. Pannella, Applied Spectrosc., 44, 1061 (1990)), we described a unique analytical method using FT-IR spectroscopy and the horizontal attenuated total reflectance (ATR) accessory for evaluating the effectiveness of topical skin protectants (TSPs) against penetration by chemical agents. We now describe the application of this method to the chemical warfare agent sulfur mustard (HD).

  4. Simultaneous determination of levodopa and carbidopa in levodopa-carbidopa tablets by ATR-FTIR spectrometry.

    PubMed

    Khanmohammadi, Mohammadreza; Mobedi, Elaheh; Garmarudi, Amir Bagheri; Mobedi, Hamid; Kargosha, Kazem

    2007-01-01

    A novel analytical procedure has been developed for quantitative determination of levodopa and carbidopa in aqueous binary solutions acidified by HCl and without any other sample pretreatment. The method is based partially on least squares treatment of data obtained by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrometry in 1211-1315 cm(-1) and 1488-1550 cm(-1) spectral regions. The simple, rapid, and accurate proposed method was applied to determine levodopa and carbidopa in Levodopa-C tablets. The statistical parameters, such as R2, RSD, SEE, SECV, LOD, and recovery were evaluated. Number of factors, scans, and resolution were optimized. In this method R2 and RSD for levodopa and carbidopa were (0.9965, 1.209) and (0.9537, 0.813), respectively.

  5. Probing proton dissociation in ionic polymers by means of in situ ATR-FTIR spectroscopy.

    PubMed

    Grosmaire, Lidwine; Castagnoni, Samuel; Huguet, Patrice; Sistat, Philippe; Boucher, Mario; Bouchard, Patrick; Bébin, Philippe; Deabate, Stefano

    2008-03-21

    The hydration process of cationic membrane protogenic groups was investigated using in situ ATR-FTIR spectroscopy. The aim of this study is to provide a relationship between the hydration degree of the membrane and the dissociation state of exchange sites inside the polymer material. IR spectra were recorded by means of an environmental device specifically manufactured to allow the control of water vapour pressure in equilibrium with the sample. The behaviour of Nafion 112 and sulfonated poly(ether ether ketone) (S-PEEK), in both proton and sodium forms, was compared. IR data, analyzed and fitted in the 800-1850 cm(-1) spectral range, gave precise information on the assignment of sulfonic group vibrational modes. The results of this study improve the understanding of the transition phenomena between dissociated and undissociated states of the grafted sites in protonic conductors.

  6. Reasoning support and uncertainty prediction in model-based vision SAR ATR

    NASA Astrophysics Data System (ADS)

    Keydel, Eric R.; Williams, Wayne D.; Sieron, Russell; Rajlich, Vasik G.; Stanhope, Stephen A.

    1999-08-01

    The MSTAR automatic target recognition (ATR) system recognizes targets by matching features predicted from a CAD model against features extracted from the unknown signature. In addition to generating signature features with high fidelity, the online Predictor in the MSTAR system must provide information that assists in efficient search of the hypothesis space as well as accounting for uncertainties in the prediction process. In this paper, we describe two capabilities implemented in the MSTAR Predictor to support this process. The first exploits the inherent traceback between predicted features and the CAD model that is integral to the predictor to enable component-wise scoring of candidate hypotheses. The second is the generation of probability density functions that characterize the fluctuation of amplitudes in the predicted signatures. The general approach for both of these is described, and example results are presented.

  7. Usage of FTIR-ATR as Non-Destructive Analysis of Selected Toxic Dyes

    NASA Astrophysics Data System (ADS)

    Bartošová, Alica; Blinová, Lenka; Sirotiak, Maroš; Michalíková, Anna

    2017-06-01

    The degradation of the environment which is due to the discharge of polluting wastewater from industrial sources poses a real problem in several countries. Textile industries use large volumes of water in their operations, discharging thus large volume of wastewater into the environment, most of which is untreated. The wastewater contains a variety of chemicals from various stages of process operations, including desizing, scouring, bleaching and dyeing. The main purpose of this paper is to introduce Infrared Spectrometry with Fourier transformation as a non-destructive method for study, identifation and rapid determination of selected representatives of cationic (Methylene Blue), azo (Congo Red, Eriochrome Black T) and nitroso (Naphthol Green B) dyes. In conjunction with the ATR technique, FTIR offers a reliable detection method of dyes without extraction by other dangerous substances. Spectral interpretation of dye spectra revealed valuable information about the identification and characterization of each group of dyes.

  8. Mobility and surfactant migration in EA/MAA latex films; ATR FT-IR spectroscopic study

    SciTech Connect

    Thorstenson, T.A.; Tebelius, L.K.; Urban, M.W.

    1993-12-31

    Although numerous factors such as compatibility, mechanical deformation, and the nature of the substrate have been addressed with respect to surfactant migration and distribution within latex films, latex suspension stability and the effects of particle flocculation are also key issues. In this paper, surfactant behavior in an ethyl acrylate/methacrylic acid/sodium dioctyl sulfosuccinate (EA/MAA/SDOSS) latex system is monitored as a function of stability of the liquid latex suspensions. Particle size data obtained using light scattering reveals an appreciable degree of flocculation over the period of study. It is found that flocculation is paralleled by a significantly increased degree of interfacial surfactant enrichment, a monitored by attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR). It is concluded that the enhanced surfactant exudation observed for flocculated latexes is due to displacement of adsorbed surfactant during the course of flocculation.

  9. Status Summary of FY16 Atom Probe Tomography Studies on UCSB ATR-2 Irradiated RPV Steels

    SciTech Connect

    Wells, Peter; Odette, G. Robert

    2016-05-01

    The University of California Santa Barbara-2 RPV Steel Irradiation experiment was awarded in 2010 by the Nuclear Science User Facility (formerly ATR NSUF) through a competitive peer review proposal process. The experiment involved irradiation of nearly 1300 samples distributed over 13 capsules. The major objective of this experiment was to better understand embrittlement behavior of reactor pressure steels at doses beyond which available data exists yet may be achieved if reactor operating licenses are extended beyond 60 years. The experiment was instrumented during irradiation and active temperature control was used to maintain the temperature at the design temperature. Six samples were selected from a large matrix of materials to perform atom probe tomography (APT) to look at formation of high dose phases. The nature and formation behavior of these phases is discussed.

  10. Analysis of spatially mismatched imagery for synthetic aperture radar ATR classification

    NASA Astrophysics Data System (ADS)

    Rupp, Chad T.; Halversen, Shawn D.; Montagnino, Lee J.; Hebert, Christina L.; Young, Matthew T.; Cassabaum, Mary L.; Ku, Neilson

    2008-04-01

    Template-based classification algorithms used with synthetic aperture radar (SAR) automatic target recognition (ATR) degrade in performance when used with spatially mismatched imagery. The degradation, caused by a spatial mismatch between the template and image, is analyzed to show acceptable tolerances for SAR systems. The mismatch between the image and template is achieved by resampling the test imagery to different pixel spacings. A consistent SAR dataset is used to examine pixel spacings between 0.1069 and 0.2539 meters with a nominal spacing of 0.2021 meters. Performance degradation is observed as the pixel spacing is adjusted, Small amounts of variation in the pixel spacing cause little change in performance and allow design engineers to set reliable tolerances. Alternatively, the results show that using templates and images collected from slightly different sensor platforms is a very real possibility with the ability to predict the classification performance.

  11. ATR and a Chk1-Aurora B pathway coordinate postmitotic genome surveillance with cytokinetic abscission

    PubMed Central

    Mackay, Douglas R.; Ullman, Katharine S.

    2015-01-01

    Aurora B regulates cytokinesis timing and plays a central role in the abscission checkpoint. Cellular events monitored by this checkpoint are beginning to be elucidated, yet signaling pathways upstream of Aurora B in this context remain poorly understood. Here we reveal a new connection between postmitotic genome surveillance and cytokinetic abscission. Underreplicated DNA lesions are known to be transmitted through mitosis and protected in newly formed nuclei by recruitment of 53BP1 and other proteins until repair takes place. We find that this genome surveillance initiates before completion of cytokinesis. Elevating replication stress increases this postmitotic process and delays cytokinetic abscission by keeping the abscission checkpoint active. We further find that ATR activity in midbody-stage cells links postmitotic genome surveillance to abscission timing and that Chk1 integrates this and other signals upstream of Aurora B to regulate when the final step in the physical separation of daughter cells occurs. PMID:25904336

  12. Direct interaction between cholesterol and phosphatidylcholines in hydrated membranes revealed by ATR-FTIR spectroscopy.

    PubMed

    Arsov, Zoran; Quaroni, Luca

    2007-11-01

    By using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and curve fitting we have examined temperature dependence and composition dependence of the shape of the carbonyl band in phosphatidylcholine/cholesterol model membranes. Membranes were hydrated either in excess water or in excess deuterated water. The studied binary mixtures exhibit different lipid phases at appropriate temperature and amount of cholesterol, among them also the so-called liquid-ordered phase. The results confirm that cholesterol has a significant indirect influence on the carbonyl band through conformational and hydration effects. This influence was interpreted in view of the known temperature composition phase diagrams for inspected binary mixtures. In addition, direct interaction was observed, which could point to the presence of hydrogen bond between cholesterol and carbonyl group. This direct interaction, though weak, might play at least a partial role in the stabilization of cholesterol-rich lipid domains in model and biological membranes.

  13. HPV 5 and 8 E6 Abrogate ATR Activity Resulting in Increased Persistence of UVB Induced DNA Damage

    PubMed Central

    Wallace, Nicholas A.; Robinson, Kristin; Howie, Heather L.; Galloway, Denise A.

    2012-01-01

    The role of the E6 oncoprotein from high-risk members of the α human papillomavirus genus in anogenital cancer has been well established. However, far less is known about the E6 protein from the β human papillomavirus genus (β-HPVs). Some β-HPVs potentially play a role in non-melanoma skin cancer development, although they are not required for tumor maintenance. Instead, they may act as a co-factor that enhances the carcinogenic potential of UV damage. Indeed, the E6 protein from certain β-HPVs (HPV 5 and 8) promotes the degradation of p300, a histone acetyl transferase involved in UV damage repair. Here, we show that the expression of HPV 5 and 8 E6 increases thymine dimer persistence as well as the likelihood of a UVB induced double strand break (DSB). Importantly, we provide a mechanism for the increased DNA damage by showing that both extended thymine dimer persistence as well as elevated DSB levels are dependent on the ability of HPV 8 E6 to promote p300 degradation. We further demonstrate that HPV 5 and 8 E6 expression reduces the mRNA and protein levels of ATR, a PI3 kinase family member that plays a key role in UV damage signaling, but that these levels remain unperturbed in cells expressing a mutated HPV 8 E6 incapable of promoting p300 degradation. We confirm that the degradation of p300 leads to a reduction in ATR protein levels, by showing that ATR levels rebound when a p300 mutant resistant to HPV 8 mediated degradation and HPV 8 E6 are co-transfected. Conversely, we show that ATR protein levels are reduced when p300 is targeted for degradation by siRNA. Moreover, we show the reduced ATR levels in HPV 5 and 8 E6 expressing cells results in delayed ATR activation and an attenuated ability of cells to phosphorylate, and as a result accumulate, p53 in response to UVB exposure, leading to significantly reduced cell cycle arrest. In conclusion, these data demonstrate that β-HPV E6 expression can enhance the carcinogenic potential of UVB exposure by

  14. Analysis of H2O in silicate glass using attenuated total reflectance (ATR) micro-FTIR spectroscopy

    USGS Publications Warehouse

    Lowenstern, Jacob B.; Pitcher, Bradley W.

    2013-01-01

    We present a calibration for attenuated total reflectance (ATR) micro-FTIR for analysis of H2O in hydrous glass. A Ge ATR accessory was used to measure evanescent wave absorption by H2O within hydrous rhyolite and other standards. Absorbance at 3450 cm−1 (representing total H2O or H2Ot) and 1630 cm−1 (molecular H2O or H2Om) showed high correlation with measured H2O in the glasses as determined by transmission FTIR spectroscopy and manometry. For rhyolite, wt%H2O=245(±9)×A3450-0.22(±0.03) and wt%H2Om=235(±11)×A1630-0.20(±0.03) where A3450 and A1630 represent the ATR absorption at the relevant infrared wavelengths. The calibration permits determination of volatiles in singly polished glass samples with spot size down to ~5 μm (for H2O-rich samples) and detection limits of ~0.1 wt% H2O. Basaltic, basaltic andesite and dacitic glasses of known H2O concentrations fall along a density-adjusted calibration, indicating that ATR is relatively insensitive to glass composition, at least for calc-alkaline glasses. The following equation allows quantification of H2O in silicate glasses that range in composition from basalt to rhyolite: wt%H2O=(ω×A3450/ρ)+b where ω = 550 ± 21, b = −0.19 ± 0.03, ρ = density, in g/cm3, and A3450 is the ATR absorbance at 3450 cm−1. The ATR micro-FTIR technique is less sensitive than transmission FTIR, but requires only a singly polished sample for quantitative results, thus minimizing time for sample preparation. Compared with specular reflectance, it is more sensitive and better suited for imaging of H2O variations in heterogeneous samples such as melt inclusions. One drawback is that the technique can damage fragile samples and we therefore recommend mounting of unknowns in epoxy prior to polishing. Our calibration should hold for any Ge ATR crystals with the same incident angle (31°). Use of a different crystal type or geometry would require measurement of several H2O-bearing standards to provide a crystal

  15. Microstructural characterization of irradiated U-7Mo/Al-5Si dispersion fuel to high fission density

    NASA Astrophysics Data System (ADS)

    Gan, J.; Miller, B. D.; Keiser, D. D.; Robinson, A. B.; Madden, J. W.; Medvedev, P. G.; Wachs, D. M.

    2014-11-01

    The fuel development program for research and test reactors calls for improved knowledge on the effect of microstructure on fuel performance in reactors. This paper summarizes the recent TEM microstructural characterization of an irradiated U-7Mo/Al-5Si dispersion fuel plate (R3R050) in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) to 5.2 × 1021 fissions/cm3. While a large fraction of the fuel grains is decorated with large bubbles, there is no evidence showing interlinking of these bubbles at the specified fission density. The attachment of solid fission product precipitates to the bubbles is likely the result of fission product diffusion into these bubbles. The process of fission gas bubble superlattice collapse appears through bubble coalescence. The results are compared with the previous TEM work on the dispersion fuels irradiated to lower fission density from the same fuel plate.

  16. Rapid classification and quantification of cocaine in seized powders with ATR-FTIR and chemometrics.

    PubMed

    Eliaerts, Joy; Dardenne, Pierre; Meert, Natalie; Van Durme, Filip; Samyn, Nele; Janssens, Koen; De Wael, Karolien

    2016-12-15

    Traditionally, fast screening for the presence of cocaine in unknown powders is performed by means of colour tests. The major drawbacks of these tests are subjective colour evaluation depending on the operator ('50 shades of blue') and a lack of selectivity. An alternative fast screening technique is Fourier Transform InfraRed (FTIR) spectrometry. This technique provides spectra that are difficult to interpret without specialized expertise and shows a lack of sensitivity for the detection of cocaine in mixtures. To overcome these limitations, a portable FTIR spectrometer using Attenuated Total Reflectance (ATR) sampling was combined with a multivariate technique, called Support Vector Machines (SVM). Representative street drug powders (n = 482), seized during the period January 2013 to July 2015, and reference powders (n = 33) were used to build and validate a classification model (n = 515) and a quantification model (n = 378). Both models were compared with the conventional chromatographic techniques. The SVM classification model showed a high sensitivity, specificity, and efficiency (99%). The SVM quantification model determined cocaine content with a root mean squared error of prediction (RMSEP) of 6% calculated over a wide working range from 4 to 99 w%. In conclusion, the developed models resulted in a clear output (cocaine detected or cocaine not detected) and a reliable estimation of the cocaine content in a wide variety of mixtures. The ATR-FTIR technique combined with SVM is a straightforward, user-friendly, and fast approach for routine classification and quantification of cocaine in seized powders. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Cutaneous approach towards clinical and pathophysiological aspects of hyperglycemia by ATR FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Eikje, Natalja Skrebova; Sota, Takayuki; Aizawa, Katsuo

    2007-07-01

    Attempts were made to non-invasively detect glucose-specific spectral signals in the skin by ATR-FTIR spectroscopy. In vivo spectra were collected from the inner wrists of healthy, prediabetes and diabetes subjects in the 750-4000 cm -1 region, with a closer assessment of the glucose-related region between 1000 and 1180 cm -1. Spectra in vivo showed glucose-specific peaks at 1030, 1080, 1118 and 1151 cm -1, as a variety of glucose solutions are found in vitro. Based on the differences of intensities at 1030 and 1118 cm -1 two spectral patterns were seen: I 1118 > I 1030 for a diabetes and I 1030> I 1118 for non-diabetes subjects. The peak at 1030 cm -1 was used to assess glucose concentrations in the skin due to its good correlation with glucose concentrations in vitro. Calculated mean values of the peak at 1030 cm -1 showed evidence of correlation with blood glucose levels when grouped as <= 140, 140-200 and >= 200 mg/dL, though there was no constant correlation between them when compared before/after OGTT or at the fasting/postprandial states. Absorbances at 1030 cm -1 were not only increased in a dose-dependent manner in a diabetes patient, but were also generally higher than in non-diabetes subjects at 30 min OGTT assessment. Also we could monitor absorbances at 1030 cm -1 and determine their changes in the skin tissue at different times of OGTT. We assume that our approach to in vivo measurement and monitoring of glucose concentrations at 1030 cm -1 may be one of the indicators to assess glucose activity level and its changes in the skin tissue, and has further implications in the study of clinical and pathophysiological aspects of hyperglycemia in diabetes and non-diabetes subjects by ATR-FTIR spectroscopy.

  18. ATR technique, an appropriate method for determining the degree of conversion in dental giomers

    NASA Astrophysics Data System (ADS)

    Prejmerean, Cristina; Prodan, Doina; Vlassa, Mihaela; Streza, Mihaela; Buruiana, Tinca; Colceriu, Loredana; Prejmerean, Vasile; Cuc, Stanca; Moldovan, Marioara

    2016-12-01

    Dental light-curing giomers were developed to combine the favourable properties of diacrylic resin composites (DRCs) and glass-ionomer cements (GICs) in a single material and to eliminate their inherent drawbacks. Giomers are characterized by their aesthetic appearance, high mechanical properties, adhesion to dental tissues as well as fluoride release and recharge abilities. The qualities of the giomers are greatly influenced by the level of conversion of the component resins. Infrared spectroscopy is one of the most largely used techniques for the determination of the degree of conversion in resin-based dental materials. However different results were obtained due to the performances of the used methods. The present work presents the determination of conversion degree in a series of dental copolymers and their corresponding giomers using transmission Fourier transform infrared spectroscopy (FTIR) and an attenuated total reflection technique (ATR) technique, respectively, the main aim being the study of the influence of the materials composition and of the light curing modes upon the achieved conversion in the cured giomers. Beautifil II commercial giomer was used as a control. A halogen lamp and a diode-blue LED lamp were used for the curing of the materials. The results showed that the composition of the resins greatly influenced the conversion. The highest conversions (up to 79%) were obtained in the case of the experimental giomers which contained the experimental Bis-GMA urethane analogue, followed by the Beautifil II giomer (61%) and experimental giomers based on commercial Bis-GMA (up to 50%), respectively. The resins light-cured by using the diode-blue LED lamp presented slightly higher conversions than the resins cured by halogen lamp. The study demonstrates the possibility to evaluate easily and reproducibly the conversion in light-curing composite materials with complex chemical composition and structure, particularly in the case of giomers by using the

  19. Rapid detection of NBOME's and other NPS on blotter papers by direct ATR-FTIR spectrometry.

    PubMed

    Coelho Neto, José

    2015-07-01

    Blotter paper is among the most common forms of consumption of new psychotropic substances (NPS), formerly referred as designer drugs. In many cases, users are misled to believe they are taking LSD when, in fact, they are taking newer and less known drugs like the NBOMEs or other substituted phenethylamines. We report our findings in quick testing of blotter papers for illicit substances like NBOMEs and other NPS by taking ATR-FTIR spectra directly from blotters seized on the streets, without any sample preparation. Both sides (front and back) of each blotter were tested. Collected data were analyzed by single- and multi-component spectral matching and submitted to chemometric discriminant analysis. Our results showed that, on 66.7% of the cases analyzed, seized blotters contained one or more types of NBOMEs, confirming the growing presence of this novel substances on the market. Matching IR signals were detected on both or just one side of the blotters and showed variable strength. Although no quantitative analysis was made, detection of these substances by the proposed approach serves as indication of variable and possibly higher dosages per blotter when compared to LSD, which showed to be below the detection limit of the applied method. Blotters containing a mescaline-like compound, later confirmed by GC-MS and LC-MS to be MAL (methallylescaline), a substance very similar to mescaline, were detected among the samples tested. Validity of direct ATR-FTIR testing was confirmed by checking the obtained results against independent GC-MS or LC-MS results for the same cases/samples. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. Tungstate (VI) sorption on hematite: An in situ ATR-FTIR probe on the mechanism.

    PubMed

    Rakshit, Sudipta; Sallman, Bryan; Davantés, Athénais; Lefèvre, Grégory

    2017-02-01

    Owing to the suspected toxicity and carcinogenicity of tungstate (VI) oxyanions [i.e. mono tungstate and several polytungstate, generally represented by W (VI)], the environmental fate of W (VI) has been widely studied. Sorption is regarded as a major mechanism by which W (VI) species are retained in the solid/water interface. Iron (hydr)oxides have been considered important environmental sinks for W (VI) species. Here we report sorption mechanisms of W (VI) on a common iron oxide mineral-hematite under environmentally relevant solution properties using in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic probes. Initial W (VI) loadings varied from 10 to 200 μM at fixed pH values ranged from 4.6 to 8.1. For pH envelop (pHs = 4.6, 5.0, 5.5, 6.0, 6.5, 7.5, and 8.1) experiments, fixed W (VI) concentrations (i.e. 10 & 200 μM) were used to understand the effects of pH. The results indicated that at acidic pH values (pH < 6.0) the sorbed polytungstate surface species are prominent at 200 μM initial W (VI) conc. The pH envelop experiments revealed that sorbed polytungstates can be present even at lower initial W (VI) conc. (i.e. 10 μM) at pH values <5.5. Overall, our in situ ATR-FTIR experiments indicated that W (VI) forms inner-sphere type bonds on hematite surface and the strength of the interaction increases with decreasing pH. In addition, initial W (VI) concentration affected the sorption mechanisms of W (VI) on hematite. Our study will aid the molecular level understanding of W (VI) retention on iron oxide surfaces. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Study of consumer fireworks post-blast residues by ATR-FTIR.

    PubMed

    Martín-Alberca, Carlos; Zapata, Félix; Carrascosa, Héctor; Ortega-Ojeda, Fernando E; García-Ruiz, Carmen

    2016-03-01

    Specific analytical procedures are requested for the forensic analysis of pre- and post-blast consumer firework samples, which present significant challenges. Up to date, vibrational spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR) have not been tested for the analysis of post-blast residues in spite of their interesting strengths for the forensic field. Therefore, this work proposes a simple and fast procedure for the sampling and analysis of consumer firework post-blast residues by a portable FTIR instrument with an Attenuated Total Reflection (ATR) accessory. In addition, the post-blast residues spectra of several consumer fireworks were studied in order to achieve the identification of their original chemical compositions. Hence, this work analysed 22 standard reagents usually employed to make consumer fireworks, or because they are related to their combustion products. Then, 5 different consumer fireworks were exploded, and their residues were sampled with dry cotton swabs and directly analysed by ATR-FTIR. In addition, their pre-blast fuses and charges were also analysed in order to stablish a proper comparison. As a result, the identification of the original chemical compositions of the post-blast samples was obtained. Some of the compounds found were potassium chlorate, barium nitrate, potassium nitrate, potassium perchlorate or charcoal. An additional study involving chemometric tools found that the results might greatly depend on the swab head type used for the sampling, and its sampling efficiency. The proposed procedure could be used as a complementary technique for the analysis of consumer fireworks post-blast residues.

  2. Benchmarking techniques for evaluation of compression transform performance in ATR applications

    NASA Astrophysics Data System (ADS)

    Schmalz, Mark S.

    2004-10-01

    Image compression is increasingly employed in applications such as medical imaging, for reducing data storage requirement, and Internet video transmission, to effectively increase channel bandwidth. Similarly, military applications such as automated target recognition (ATR) often employ compression to achieve storage and communication efficiencies, particularly to enhance the effective bandwidth of communication channels whose throughput suffers, for example, from overhead due to error correction/detection or encryption. In the majority of cases, lossy compression is employed due the resultant low bit rates (high compression ratio). However, lossy compression produces artifacts in decompressed imagery that can confound ATR processes applied to such imagery, thereby reducing the probability of detection (Pd) and possibly increasing the rate or number of false alarms (Rfa or Nfa). In this paper, the authors' previous research in performance measurement of compression transforms is extended to include (a) benchmarking algorithms and software tools, (b) a suite of error exemplars that are designed to elicit compression transform behavior in an operationally relevant context, and (c) a posteriori analysis of performance data. The following transforms are applied to a suite of 64 error exemplars: Visual Pattern Image Coding (VPIC [1]), Vector Quantization with a fast codebook search algorithm (VQ [2,3]), JPEG and a preliminary implementation of JPEG 2000 [4,5], and EBLAST [6-8]. Compression ratios range from 2:1 to 200:1, and various noise levels and types are added to the error exemplars to produce a database of 7,680 synthetic test images. Several global and local (e.g., featural) distortion measures are applied to the decompressed test imagery to provide a basis for rate-distortion and rate-performance analysis as a function of noise and compression transform type.

  3. Fuel composition

    SciTech Connect

    Badger, S.L.

    1983-09-20

    A composition useful, inter alia, as a fuel, is based on ethyl alcohol denatured with methylisobutyl alcohol and kerosene, which is mixed with xylenes and isopropyl alcohol. The xylenes and isopropyl alcohol act with the denaturizing agents to raise the flash point above that of ethyl alcohol alone and also to mask the odor and color the flame, thus making the composition safer for use as a charcoal lighter or as a fuel for e.g. patio lamps.

  4. FABRICATION OF URANIUM OXYCARBIDE KERNELS AND COMPACTS FOR HTR FUEL

    SciTech Connect

    Dr. Jeffrey A. Phillips; Eric L. Shaber; Scott G. Nagley

    2012-10-01

    As part of the program to demonstrate tristructural isotropic (TRISO)-coated fuel for the Next Generation Nuclear Plant (NGNP), Advanced Gas Reactor (AGR) fuel is being irradiation tested in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). This testing has led to improved kernel fabrication techniques, the formation of TRISO fuel particles, and upgrades to the overcoating, compaction, and heat treatment processes. Combined, these improvements provide a fuel manufacturing process that meets the stringent requirements associated with testing in the AGR experimentation program. Researchers at Idaho National Laboratory (INL) are working in conjunction with a team from Babcock and Wilcox (B&W) and Oak Ridge National Laboratory (ORNL) to (a) improve the quality of uranium oxycarbide (UCO) fuel kernels, (b) deposit TRISO layers to produce a fuel that meets or exceeds the standard developed by German researches in the 1980s, and (c) develop a process to overcoat TRISO particles with the same matrix material, but applies it with water using equipment previously and successfully employed in the pharmaceutical industry. A primary goal of this work is to simplify the process, making it more robust and repeatable while relying less on operator technique than prior overcoating efforts. A secondary goal is to improve first-pass yields to greater than 95% through the use of established technology and equipment. In the first test, called “AGR-1,” graphite compacts containing approximately 300,000 coated particles were irradiated from December 2006 to November 2009. The AGR-1 fuel was designed to closely replicate many of the properties of German TRISO-coated particles, thought to be important for good fuel performance. No release of gaseous fission product, indicative of particle coating failure, was detected in the nearly 3-year irradiation to a peak burn up of 19.6% at a time-average temperature of 1038–1121°C. Before fabricating AGR-2 fuel, each

  5. ATR kinase is required for global genomic nucleotide excision repair exclusively during S phase in human cells

    PubMed Central

    Auclair, Yannick; Rouget, Raphael; Affar, El Bachir; Drobetsky, Elliot A.

    2008-01-01

    Global-genomic nucleotide excision repair (GG-NER) is the only pathway available to humans for removal, from the genome overall, of highly genotoxic helix-distorting DNA adducts generated by many environmental mutagens and certain chemotherapeutic agents, e.g., UV-induced 6–4 photoproducts (6–4PPs) and cyclobutane pyrimidine dimers (CPDs). The ataxia telangiectasia and rad-3-related kinase (ATR) is rapidly activated in response to UV-induced replication stress and proceeds to phosphorylate a plethora of downstream effectors that modulate primarily cell cycle checkpoints but also apoptosis and DNA repair. To investigate whether this critical kinase might participate in the regulation of GG-NER, we developed a novel flow cytometry-based DNA repair assay that allows precise evaluation of GG-NER kinetics as a function of cell cycle. Remarkably, inhibition of ATR signaling in primary human lung fibroblasts by treatment with caffeine, or with siRNA specifically targeting ATR, resulted in total inhibition of 6–4PP removal during S phase, whereas cells repaired normally during either G0/G1 or G2/M. Similarly striking S-phase-specific defects in GG-NER of both 6–4PPs and CPDs were documented in ATR-deficient Seckel syndrome skin fibroblasts. Finally, among six diverse model human tumor strains investigated, three manifested complete abrogation of 6–4PP repair exclusively in S-phase populations. Our data reveal a highly novel role for ATR in the regulation of GG-NER uniquely during S phase of the cell cycle, and indicate that many human cancers may be characterized by a defect in this regulation. PMID:19004803

  6. IGF-1R inhibition sensitizes breast cancer cells to ATM-related kinase (ATR) inhibitor and cisplatin

    PubMed Central

    O'Flanagan, Ciara H.; O'shea, Sandra; Lyons, Amy; Fogarty, Fionola M.; McCabe, Nuala; Kennedy, Richard D.; O'Connor, Rosemary

    2016-01-01

    The complexity of the IGF-1 signalling axis is clearly a roadblock in targeting this receptor in cancer therapy. Here, we sought to identify mediators of resistance, and potential co-targets for IGF-1R inhibition. By using an siRNA functional screen with the IGF-1R tyrosine kinase inhibitor (TKI) BMS-754807 in MCF-7 cells we identified several genes encoding components of the DNA damage response (DDR) pathways as mediators of resistance to IGF-1R kinase inhibition. These included ATM and Ataxia Telangiectasia and RAD3-related kinase (ATR). We also observed a clear induction of DDR in cells that were exposed to IGF-1R TKIs (BMS-754807 and OSI-906) as indicated by accumulation of γ-H2AX, and phosphorylated Chk1. Combination of the IGF-1R/IR TKIs with an ATR kinase inhibitor VE-821 resulted in additive to synergistic cytotoxicity compared to either drug alone. In MCF-7 cells with stably acquired resistance to the IGF-1R TKI (MCF-7-R), DNA damage was also observed, and again, dual inhibition of the ATR kinase and IGF-1R/IR kinase resulted in synergistic cytotoxicity. Interestingly, dual inhibition of ATR and IGF-1R was more effective in MCF-7-R cells than parental cells. IGF-1R TKIs also potentiated the effects of cisplatin in a panel of breast cancer cell lines. Overall, our findings identify induction of DDR by IGF-1R kinase inhibition as a rationale for co-targeting the IGF-1R with ATR kinase inhibitors or cisplatin, particularly in cells with acquired resistance to TKIs. PMID:27472395

  7. PU Disposition in Russian VVERs: Physics Studies of Lead Test Assembly Design

    SciTech Connect

    Ellis, R.J.

    2000-05-07

    As part of Fissile Materials Disposition Program (FMDP) physics support was given to the design of a MOX lead test assembly (LTA) for use in Russian VVER nuclear reactors. This paper discusses some of the pertinent findings and assessments for two distinct LTA designs for weapons-grade (WG) Pu dispositioning in Russian VVER-1000 nuclear reactors. The two assessed MOX LTA designs are the graded-zone full MOX LTA and the Island LTA (2 central zones of MOX pins surrounded by UO{sub 2} pins). The process of optimizing the graded Pu-content by zone in the fuel assembly is discussed. Eigenvalue and power peaking comparisons are made as a function of fuel burnup. Zero-power reactivity effects were calculated for the different LTA options. For the ORNL results, the n,{gamma}-transport lattice physics code HELIOS-1.4 was used with nuclear data libraries (based on ENDF/B-VI) in 89 and 190 neutron energy groups. Some comparisons are made between the ORNL HELIOS results and corresponding Russian LTA calculations by the RRC-KI (Kurchatov Institute) using the code TVS-M. Also in this paper, pertinent results are discussed from a study of void reactivity effects for LEU, RG MOX and WG MOX fuels in PWR and VVER-1000 nuclear reactors. These void reactivity calculations were performed for a large range of LEU enrichments (2-20 wt% {sup 235}U), and large ranges of Pu-content (2-20 wt% Pu) in RG and WG MOX fuel.

  8. Fission Product Monitoring of TRISO Coated Fuel For The Advanced Gas Reactor -1 Experiment

    SciTech Connect

    Dawn M. Scates; John K. Hartwell; John b. Walter

    2010-10-01

    The US Department of Energy has embarked on a series of tests of TRISO-coated particle reactor fuel intended for use in the Very High Temperature Reactor (VHTR) as part of the Advanced Gas Reactor (AGR) program. The AGR-1 TRISO fuel experiment, currently underway, is the first in a series of eight fuel tests planned for irradiation in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The AGR-1 experiment reached a peak compact averaged burn up of 9% FIMA with no known TRISO fuel particle failures in March 2008. The burnup goal for the majority of the fuel compacts is to have a compact averaged burnup greater than 18% FIMA and a minimum compact averaged burnup of 14% FIMA. At the INL the TRISO fuel in the AGR-1 experiment is closely monitored while it is being irradiated in the ATR. The effluent monitoring system used for the AGR-1 fuel is the Fission Product Monitoring System (FPMS). The FPMS is a valuable tool that provides near real-time data indicative of the AGR-1 test fuel performance and incorporates both high-purity germanium (HPGe) gamma-ray spectrometers and sodium iodide [NaI(Tl)] scintillation detector-based gross radiation monitors. To quantify the fuel performance, release-to-birth ratios (R/B’s) of radioactive fission gases are computed. The gamma-ray spectra acquired by the AGR-1 FPMS are analyzed and used to determine the released activities of specific fission gases, while a dedicated detector provides near-real time count rate information. Isotopic build up and depletion calculations provide the associated isotopic birth rates. This paper highlights the features of the FPMS, encompassing the equipment, methods and measures that enable the calculation of the release-to-birth ratios. Some preliminary results from the AGR-1 experiment are also presented.

  9. Fission Product Monitoring of TRISO Coated Fuel For The Advanced Gas Reactor -1 Experiment

    SciTech Connect

    Dawn M. Scates; John K Hartwell; John B. Walter

    2008-09-01

    The US Department of Energy has embarked on a series of tests of TRISO-coated particle reactor fuel intended for use in the Very High Temperature Reactor (VHTR) as part of the Advanced Gas Reactor (AGR) program. The AGR-1 TRISO fuel experiment, currently underway, is the first in a series of eight fuel tests planned for irradiation in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The AGR-1 experiment reached a peak compact averaged burn up of 9% FIMA with no known TRISO fuel particle failures in March 2008. The burnup goal for the majority of the fuel compacts is to have a compact averaged burnup greater than 18% FIMA and a minimum compact averaged burnup of 14% FIMA. At the INL the TRISO fuel in the AGR-1 experiment is closely monitored while it is being irradiated in the ATR. The effluent monitoring system used for the AGR-1 fuel is the Fission Product Monitoring System (FPMS). The FPMS is a valuable tool that provides near real-time data indicative of the AGR-1 test fuel performance and incorporates both high-purity germanium (HPGe) gamma-ray spectrometers and sodium iodide [NaI(Tl)] scintillation detector-based gross radiation monitors. To quantify the fuel performance, release-to-birth ratios (R/B’s) of radioactive fission gases are computed. The gamma-ray spectra acquired by the AGR-1 FPMS are analyzed and used to determine the released activities of specific fission gases, while a dedicated detector provides near-real time count rate information. Isotopic build up and depletion calculations provide the associated isotopic birth rates. This paper highlights the features of the FPMS, encompassing the equipment, methods and measures that enable the calculation of the release-to-birth ratios. Some preliminary results from the AGR-1 experiment are also presented.

  10. Effects of Water in Canisters Containing DOE Spent Nuclear Fuel

    SciTech Connect

    P. A. Lessing

    1998-10-01

    This document is a starting analysis in an attempt to quantify the potential of problems resulting from the presence of condensed water and water vapor in sealed storage canisters containing spent nuclear fuel (SNF). Of the 55 spent fuel types, it was determined that only three types required study to evaluate the effects of water, these types were represented by: (1) zirconium clad N-Reactor fuel, (2) aluminum clad Advanced Test Reactor (ATR) or Materials Test Reactor (MTR) fuel, (3) damaged and/or melted zirconium clad Three Mile Island (TMI) fuel. The spent fuel types were briefly described and potential problems were generalized into four catagories: (1) effects of water and the source(s) of that water, (2) effects of hydrogen generated from water, (3) pyrophoricity of uranium hydride, (4) swelling or cavitation. An extensive literature search was conducted, chemical reactions considered, and simple pressurization sensitivity calculations performed. Using the available information, conclusions were drawn and issues identified that need further consideration or analysis.

  11. Bench-Scale Monolith Autothermal Reformer Catalyst Screening Evaluations in a Micro-Reactor With Jet-A Fuel

    NASA Technical Reports Server (NTRS)

    Tomsik, Thomas M.; Yen, Judy C.H.; Budge, John R.

    2006-01-01

    Solid oxide fuel cell systems used in the aerospace or commercial aviation environment require a compact, light-weight and highly durable catalytic fuel processor. The fuel processing method considered here is an autothermal reforming (ATR) step. The ATR converts Jet-A fuel by a reaction with steam and air forming hydrogen (H2) and carbon monoxide (CO) to be used for production of electrical power in the fuel cell. This paper addresses the first phase of an experimental catalyst screening study, looking at the relative effectiveness of several monolith catalyst types when operating with untreated Jet-A fuel. Six monolith catalyst materials were selected for preliminary evaluation and experimental bench-scale screening in a small 0.05 kWe micro-reactor test apparatus. These tests were conducted to assess relative catalyst performance under atmospheric pressure ATR conditions and processing Jet-A fuel at a steam-to-carbon ratio of 3.5, a value higher than anticipated to be run in an optimized system. The average reformer efficiencies for the six catalysts tested ranged from 75 to 83 percent at a constant gas-hourly space velocity of 12,000 hr 1. The corresponding hydrocarbon conversion efficiency varied from 86 to 95 percent during experiments run at reaction temperatures between 750 to 830 C. Based on the results of the short-duration 100 hr tests reported herein, two of the highest performing catalysts were selected for further evaluation in a follow-on 1000 hr life durability study in Phase II.

  12. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  13. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  14. Differential Processing of Low and High LET Radiation Induced DNA Damage: Investigation of Switch from ATM to ATR Signaling

    NASA Technical Reports Server (NTRS)

    Saha, Janapriya; Wang, Minli; Hada, Megumi; Cucinotta, Francis A.

    2011-01-01

    The members of the phosphatidylinositol kinase-like kinase family of proteins namely ataxia-telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR) are directly responsible for the maintenance of genomic integrity by mounting DDR through signaling and facilitating the recruitment of repair factors at the sites of DNA damage along with coordinating the deployment of cell cycle checkpoints to permit repair by phosphorylating Checkpoint kinase Chk1, Chk2 and p53. High LET radiation from GCR (Galactic Cosmic Rays) consisting mainly of protons and high energy and charged (HZE) particles from SPE (Solar Particle Event) pose a major health risk for astronauts on their space flight missions. The determination of these risks and the design of potential safeguards require sound knowledge of the biological consequences of lesion induction and the capability of the cells to counter them. We here strive to determine the coordination of ATM and ATR kinases at the break sites directly affecting checkpoint signaling and DNA repair and whether differential processing of breaks induced by low and high LET radiation leads to possible augmentation of swap of these damage sensors at the sites of DNA damage. Exposure of cells to IR triggers rapid autophosphorylation of serine-1981 that causes dimer dissociation and initiates monomer formation of ATM. ATM kinase activity depends on the disruption of the dimer, which allows access and phosphorylation of downstream ATM substrates like Chk2. Evidence suggests that ATM is activated by the alterations in higher-order chromatin structure although direct binding of ATM to DSB ends may be a crucial step in its activation. On the other hand, in case of ATR, RPA (replication protein A)-coated ssDNA (single-stranded DNA) generated as a result of stalled DNA replication or during processing of chromosomal lesions is crucial for the localization of ATR to sites of DNA damage in association with ATR-interacting protein (ATRIP). Although the

  15. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, Ralph E.

    1988-01-01

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream I and spent fuel stream II. Spent fuel stream I is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream I and exhaust stream II, and exhaust stream I is vented. Exhaust stream II is mixed with spent fuel stream II to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells.

  16. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, R.E.

    1988-03-08

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream 1 and spent fuel stream 2. Spent fuel stream 1 is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream 1 and exhaust stream 2, and exhaust stream 1 is vented. Exhaust stream 2 is mixed with spent fuel stream 2 to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells. 1 fig.

  17. FUEL ELEMENT

    DOEpatents

    Fortescue, P.; Zumwalt, L.R.

    1961-11-28

    A fuel element was developed for a gas cooled nuclear reactor. The element is constructed in the form of a compacted fuel slug including carbides of fissionable material in some cases with a breeder material carbide and a moderator which slug is disposed in a canning jacket of relatively impermeable moderator material. Such canned fuel slugs are disposed in an elongated shell of moderator having greater gas permeability than the canning material wherefore application of reduced pressure to the space therebetween causes gas diffusing through the exterior shell to sweep fission products from the system. Integral fission product traps and/or exterior traps as well as a fission product monitoring system may be employed therewith. (AEC)

  18. Fuel bundle

    SciTech Connect

    Lui, C.K.

    1989-04-04

    This patent describes a method of forming a fuel bundle of a nuclear reactor. The method consists of positioning the fuel rods in the bottom plate, positioning the tie rod in the bottom plate with the key passed through the receptacle to the underside of the bottom plate and, after the tie rod is so positioned, turning the tie rod so that the key is in engagement with the underside of the bottom plate. Thereafter mounting the top plate is mounted in engagement with the fuel rods with the upper end of the tie rod extending through the opening in the top plate and extending above the top plate, and the tie rod is secured to the upper side of sid top plate thus simultaneously securing the key to the underside of the bottom plate.

  19. Variability and robustness of scatterers in HRR/ISAR ground target data and its influence on the ATR performance

    NASA Astrophysics Data System (ADS)

    Schumacher, R.; Schimpf, H.; Schiller, J.

    2011-06-01

    The most challenging problem of Automatic Target Recognition (ATR) is the extraction of robust and independent target features which describe the target unambiguously. These features have to be robust and invariant in different senses: in time, between aspect views (azimuth and elevation angle), between target motion (translation and rotation) and between different target variants. Especially for ground moving targets in military applications an irregular target motion is typical, so that a strong variation of the backscattered radar signal with azimuth and elevation angle makes the extraction of stable and robust features most difficult. For ATR based on High Range Resolution (HRR) profiles and / or Inverse Synthetic Aperture Radar (ISAR) images it is crucial that the reference dataset consists of stable and robust features, which, among others, will depend on the target aspect and depression angle amongst others. Here it is important to find an adequate data grid for an efficient data coverage in the reference dataset for ATR. In this paper the variability of the backscattered radar signals of target scattering centers is analyzed for different HRR profiles and ISAR images from measured turntable datasets of ground targets under controlled conditions. Especially the dependency of the features on the elevation angle is analyzed regarding to the ATR of large strip SAR data with a large range of depression angles by using available (I)SAR datasets as reference. In this work the robustness of these scattering centers is analyzed by extracting their amplitude, phase and position. Therefore turntable measurements under controlled conditions were performed targeting an artificial military reference object called STANDCAM. Measures referring to variability, similarity, robustness and separability regarding the scattering centers are defined. The dependency of the scattering behaviour with respect to azimuth and elevation variations is analyzed. Additionally generic types

  20. FUEL ELEMENT

    DOEpatents

    Howard, R.C.; Bokros, J.C.

    1962-03-01

    A fueled matrlx eontnwinlng uncomblned carbon is deslgned for use in graphlte-moderated gas-cooled reactors designed for operatlon at temperatures (about 1500 deg F) at which conventional metallic cladding would ordlnarily undergo undesired carburization or physical degeneratlon. - The invention comprlses, broadly a fuel body containlng uncombined earbon, clad with a nickel alloy contalning over about 28 percent by' weight copper in the preferred embodlment. Thls element ls supporirted in the passageways in close tolerance with the walls of unclad graphite moderator materlal. (AEC)

  1. Characterization of LWRS Hybrid SiC-CMC-Zircaloy-4 Fuel Cladding after Gamma Irradiation

    SciTech Connect

    Isabella J van Rooyen

    2012-09-01

    The purpose of the gamma irradiation tests conducted at the Idaho National Laboratory (INL) was to obtain a better understanding of chemical interactions and potential changes in microstructural properties of a mock-up hybrid nuclear fuel cladding rodlet design (unfueled) in a simulated PWR water environment under irradiation conditions. The hybrid fuel rodlet design is being investigated under the Light Water Reactor Sustainability (LWRS) program for further development and testing of one of the possible advanced LWR nuclear fuel cladding designs. The gamma irradiation tests were performed in preparation for neutron irradiation tests planned for a silicon carbide (SiC) ceramic matrix composite (CMC) zircaloy-4 (Zr-4) hybrid fuel rodlet that may be tested in the INL Advanced Test Reactor (ATR) if the design is selected for further development and testing

  2. Deposition from dopamine solutions at Ge substrates: an in situ ATR-FTIR study.

    PubMed

    Müller, Martin; Kessler, Bernd

    2011-10-18

    Deposition from dopamine (DA) solutions at germanium (Ge) model substrates was monitored under stationary conditions using surface sensitive in situ attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. ATR-FTIR spectra of the interfacial organic layer formed upon contact of TRIS buffered aqueous DA solutions to a Ge internal reflection element (IRE) showed conveniently strong diagnostic IR absorption bands, which were increasing with deposition time up to at least 6 h. Comparison of IR spectra of unreacted pristine DA, surface reacted, and bulk reacted material confirmed chemical reactions of DA to a polymerizate according to the literature. The found IR bands could be assigned to aromatic as well as C-O single bond moieties. The kinetic courses of the diagnostic band integrals showed an initial increase and saturation of the deposition after around 300 min, which could be empirically represented by an exponential damping function revealing a rather small kinetic constant. Highest deposition levels were found at pH = 8.5 (TRIS buffer or NaOH) in contrast to pH = 6.2, where no deposition occurred. Minor deposition was found in the presence of salt or at ZnSe instead of Ge due to the absence of reactive hydroxyl groups. The concentration dependence of DA deposition showed an initial increase and a saturation beginning at around 0.4 mg/mL (0.0022 M), where around 50 nm thick films featuring granular surface morphologies are formed. The adsorbed species are suggested to be smaller bulk reacted DA polymerizate particles with reactive end groups. Rinsing the formed films by pure TRIS buffer resulted in a time dependent release of deposited organic material by ≈23%, which could be represented by an exponential decay function. A saturation of the release after around 100 min and a larger kinetic constant compared to deposition could be determined. The released material is suggested to be larger aggregated bulk reacted DA polymerizate particles

  3. Fuels characterization studies. [jet fuels

    NASA Technical Reports Server (NTRS)

    Seng, G. T.; Antoine, A. C.; Flores, F. J.

    1980-01-01

    Current analytical techniques used in the characterization of broadened properties fuels are briefly described. Included are liquid chromatography, gas chromatography, and nuclear magnetic resonance spectroscopy. High performance liquid chromatographic ground-type methods development is being approached from several directions, including aromatic fraction standards development and the elimination of standards through removal or partial removal of the alkene and aromatic fractions or through the use of whole fuel refractive index values. More sensitive methods for alkene determinations using an ultraviolet-visible detector are also being pursued. Some of the more successful gas chromatographic physical property determinations for petroleum derived fuels are the distillation curve (simulated distillation), heat of combustion, hydrogen content, API gravity, viscosity, flash point, and (to a lesser extent) freezing point.

  4. Future Fuel.

    ERIC Educational Resources Information Center

    Stover, Del

    1991-01-01

    Tough new environmental laws, coupled with fluctuating oil prices, are likely to prompt hundreds of school systems to examine alternative fuels. Literature reviews and interviews with 45 government, education, and industry officials provided data for a comparative analysis of gasoline, diesel, natural gas, methanol, and propane. (MLF)

  5. Future Fuel.

    ERIC Educational Resources Information Center

    Stover, Del

    1991-01-01

    Tough new environmental laws, coupled with fluctuating oil prices, are likely to prompt hundreds of school systems to examine alternative fuels. Literature reviews and interviews with 45 government, education, and industry officials provided data for a comparative analysis of gasoline, diesel, natural gas, methanol, and propane. (MLF)

  6. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  7. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  8. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  9. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  10. Prediction of peroxide value in omega-3 rich microalgae oil by ATR-FTIR spectroscopy combined with chemometrics.

    PubMed

    Cebi, Nur; Yilmaz, Mustafa Tahsin; Sagdic, Osman; Yuce, Hande; Yelboga, Emrah

    2017-06-15

    Our work explored, for the first time, monitoring peroxide value (PV) of omega-3 rich algae oil using ATR-FTIR spectroscopic technique. The PV of the developed method was compared by that obtained by standard method of Association of Official Analytical Chemists (AOAC). In this study, peak area integration (PAI), Partial Least Squares Regression (PLSR), and Principal Component Regression (PCR) were used as the calibration techniques. PV obtained by the AOAC method and by FTIR-ATR technique were well correlated considering the peak area related to trans double bonds and chemometrics techniques of PLSR and PCR. Calibration model was established using the band with a peak point at 966cm(-1) (990-940cm(-1)) related to CH out of plane deformation vibration of trans double bond. Algae oil oxidation could be successfully quantified using PAI, PLSR and PCR techniques. Additionally, hierarchical cluster analysis was performed and significant discrimination was observed coherently with oxidation process.

  11. Thermal behaviors of stainless steel tube based GeO2 ATR hollow fibers for transmitting CO2 laser radiations

    NASA Astrophysics Data System (ADS)

    Wang, Xu; Wang, Lin; Fu, Xiaohong; Jing, Chengbin; Yue, Fangyu; Yang, Pingxiong; Chu, Junhao

    2017-10-01

    The stainless steel (SUS) capillary tube attenuated total reflective (ATR) GeO2 hollow waveguide has advantages of low fabrication cost, strong mechanic strength and low transmission loss. It can find laser power delivery applications such as laser surgery, and material processing. However, the temperature rise of the operating waveguide may affect the laser delivery stability and the laser surgery safety. The thermal behaviors of the SUS ATR hollow fiber transmitting CO2 laser were investigated theoretically and experimentally in this work. Both theoretic simulations and experimental results disclose the periodic oscillatory behavior of the fiber temperature. The influence of input laser power on fiber temperature has been quantitatively discussed. A maximum input laser power of 23 W is predicted for laser surgery in which case the fiber temperature had better be lower than 47 °C to avoid tissue scalds. An input laser power smaller than 137 W is suggested preventing the fiber from being overheated (150 °C).

  12. Blood glucose measurement in vivo using hollow-fiber based, mid-infrared ATR probe with multi-reflection prism

    NASA Astrophysics Data System (ADS)

    Kino, Saiko; Omori, Suguru; Matsuura, Yuji

    2016-03-01

    An attenuated-total-reflection (ATR), mid-infrared spectroscopy system that consists of hollow optical fibers, a trapezoidal multi-reflection ATR prism, and a conventional FT-IR spectrometer has been developed to measure blood glucose levels. Owing to the low transmission loss and high flexibility of the hollow-optical fiber, the system can measure any sites of the human body where blood capillaries are close to the surface of mucosa, such as inner lips. Using a multi-reflection prism brought about higher sensitivity, and the flat and wide contact surface of the prism resulted in higher measurement reproducibility. The results of in-vivo measurement of human inner lips showed the feasibility of the proposed system, and the measurement errors were within 20%.

  13. ATR-FT-IR spectroscopy in the region of 500-230 cm(-1) for identification of inorganic red pigments.

    PubMed

    Vahur, Signe; Knuutinen, Ulla; Leito, Ivo

    2009-08-15

    It is demonstrated that micro-ATR-FT-IR in the low wave number range (500-230 cm(-1)) can be well used for identification of pigments in paint samples thereby markedly extending the possibilities of pigment identification by ATR-IR spectroscopy into the realm of pigments having no absorptions in the mid-IR region. Reference spectra of pigments can be conveniently obtained by mixing them with linseed oil in approximately 1:1 mass ratio. Vermilion (or cinnabar), read lead, different red iron oxide pigments and cadmium red can be identified. In some cases the method can be used alone for pigment identification and in many cases it provides useful additional evidence for pigment identification using other instrumental techniques (electron microprobe analysis, XRF, optical microscopy).

  14. Determination of chemical changes in heat-treated wood using ATR-FTIR and FT Raman spectrometry.

    PubMed

    Özgenç, Özlem; Durmaz, Sefa; Boyaci, Ismail Hakki; Eksi-Kocak, Haslet

    2017-01-15

    In this study, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and Fourier-transform Raman (FT-Raman) spectroscopy techniques were used to determine changes in the chemical structure of heat-treated woods. For this purpose, scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.), and oriental spruce (Picea orientalis L.) wood species were heat-treated at different temperatures. The effect of chemical changes on the FT-Raman and ATR-FTIR bands or ratios of heat-treated wood was related with the OH association of cellulose, functional groups, and the aromatic system of lignin. The effects of heat treatment on the carbohydrate and lignin peaks varied depending on the wood species. The spectral changes that occurred after heat treatment reflected the progress of the condensation reaction of lignin. Degradation of hemicelluloses led to a decrease in free hydroxyl groups. High temperature caused crystalline cellulose to increase due to the degradation of amorphous cellulose.

  15. ATR-FT-IR spectroscopy in the region of 500-230 cm -1 for identification of inorganic red pigments

    NASA Astrophysics Data System (ADS)

    Vahur, Signe; Knuutinen, Ulla; Leito, Ivo

    2009-08-01

    It is demonstrated that micro-ATR-FT-IR in the low wave number range (500-230 cm -1) can be well used for identification of pigments in paint samples thereby markedly extending the possibilities of pigment identification by ATR-IR spectroscopy into the realm of pigments having no absorptions in the mid-IR region. Reference spectra of pigments can be conveniently obtained by mixing them with linseed oil in approximately 1:1 mass ratio. Vermilion (or cinnabar), read lead, different red iron oxide pigments and cadmium red can be identified. In some cases the method can be used alone for pigment identification and in many cases it provides useful additional evidence for pigment identification using other instrumental techniques (electron microprobe analysis, XRF, optical microscopy).

  16. Major Roles for Pyrimidine Dimers, Nucleotide Excision Repair, and ATR in the Alternative Splicing Response to UV Irradiation.

    PubMed

    Muñoz, Manuel J; Nieto Moreno, Nicolás; Giono, Luciana E; Cambindo Botto, Adrián E; Dujardin, Gwendal; Bastianello, Giulia; Lavore, Stefania; Torres-Méndez, Antonio; Menck, Carlos F M; Blencowe, Benjamin J; Irimia, Manuel; Foiani, Marco; Kornblihtt, Alberto R

    2017-03-21

    We have previously found that UV irradiation promotes RNA polymerase II (RNAPII) hyperphosphorylation and subsequent changes in alternative splicing (AS). We show now that UV-induced DNA damage is not only necessary but sufficient to trigger the AS response and that photolyase-mediated removal of the most abundant class of pyrimidine dimers (PDs) abrogates the global response to UV. We demonstrate that, in keratinocytes, RNAPII is the target, but not a sensor, of the signaling cascade initiated by PDs. The UV effect is enhanced by inhibition of gap-filling DNA synthesis, the last step in the nucleotide excision repair pathway (NER), and reduced by the absence of XPE, the main NER sensor of PDs. The mechanism involves activation of the protein kinase ATR that mediates the UV-induced RNAPII hyperphosphorylation. Our results define the sequence UV-PDs-NER-ATR-RNAPII-AS as a pathway linking DNA damage repair to the control of both RNAPII phosphorylation and AS regulation.

  17. Historical perspective and modern applications of Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR).

    PubMed

    Blum, Marc-Michael; John, Harald

    2012-01-01

    Vibrational spectroscopy has a long history as an important spectroscopic method in chemical and pharmaceutical analysis. Instrumentation for infrared (IR) spectroscopy was revolutionized by the introduction of Fourier Transform Infrared (FTIR) spectrometers. In addition, easier sampling combined with better sample-to-sample reproducibility and user-to-user spectral variation became available with attenuated total reflectance (ATR) probes and their application for in situ IR spectroscopy. These innovations allow many new applications in chemical and pharmaceutical analysis, such as the use of IR spectroscopy in Process Analytical Chemistry (PAC), the quantitation of drugs in complex matrix formulations, the analysis of protein binding and function and in combination with IR microscopy to the emergence of IR imaging technologies. The use of ATR-FTIR instruments in forensics and first response to 'white powder' incidents is also discussed. A short overview is given in this perspective article with the aim to renew and intensify interest in IR spectroscopy.

  18. A modified golden gate attenuated total reflection (ATR) cell for monitoring phase transitions in multicomponent fluids at high temperatures.

    PubMed

    Novitskiy, Alexander A; Ke, Jie; Comak, Gurbuz; Poliakoff, Martyn; George, Michael W

    2011-08-01

    A new continuous flow method using attenuated total reflection infrared (ATR-IR) spectroscopy has been developed for monitoring phase transitions in multicomponent fluids at high pressures and temperatures. Our approach uses Fourier transform infrared (FT-IR) and a modified Golden Gate attenuated total reflection (ATR) cell and exploits the fact that the absorbance of a vapor is much lower than that of the corresponding liquid to monitor the phase transition between vapor and liquid. We demonstrate that this method can provide quantitative measurements on both the dew point and the bubble point. We have validated our approach using three single-component systems (EtOH, MeOH, and H(2)O) and a binary system of EtOH + H(2)O, monitoring phase transitions at temperature up to 300 °C and pressure up to 10 MPa.

  19. Determination of chemical changes in heat-treated wood using ATR-FTIR and FT Raman spectrometry

    NASA Astrophysics Data System (ADS)

    Özgenç, Özlem; Durmaz, Sefa; Boyaci, Ismail Hakki; Eksi-Kocak, Haslet

    2017-01-01

    In this study, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and Fourier-transform Raman (FT-Raman) spectroscopy techniques were used to determine changes in the chemical structure of heat-treated woods. For this purpose, scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.), and oriental spruce (Picea orientalis L.) wood species were heat-treated at different temperatures. The effect of chemical changes on the FT-Raman and ATR-FTIR bands or ratios of heat-treated wood was related with the OH association of cellulose, functional groups, and the aromatic system of lignin. The effects of heat treatment on the carbohydrate and lignin peaks varied depending on the wood species. The spectral changes that occurred after heat treatment reflected the progress of the condensation reaction of lignin. Degradation of hemicelluloses led to a decrease in free hydroxyl groups. High temperature caused crystalline cellulose to increase due to the degradation of amorphous cellulose.

  20. Induction of ATM/ATR pathway combined with Vγ2Vδ2 T cells enhances cytotoxicity of ovarian cancer cells.

    PubMed

    Lu, Jingwei; Das, Manjusri; Kanji, Suman; Aggarwal, Reeva; Joseph, Matthew; Ray, Alo; Shapiro, Charles L; Pompili, Vincent J; Das, Hiranmoy

    2014-07-01

    Many ovarian cancer cells express stress-related molecule MICA/B on their surface that is recognized by Vγ2Vδ2 T cells through their NKG2D receptor, which is transmitted to downstream stress-signaling pathway. However, it is yet to be established how Vγ2Vδ2 T cell-mediated recognition of MICA/B signal is transmitted to downstream stress-related molecules. Identifying targeted molecules would be critical to develop a better therapy for ovarian cancer cells. It is well established that ATM/ATR signal transduction pathways, which is modulated by DNA damage, replication stress, and oxidative stress play central role in stress signaling pathway regulating cell cycle checkpoint and apoptosis. We investigated whether ATM/ATR and its down stream molecules affect Vγ2Vδ2 T cell-mediated cytotoxicity. Herein, we show that ATM/ATR pathway is modulated in ovarian cancer cells in the presence of Vγ2Vδ2 T cells. Furthermore, downregulation of ATM pathway resulted downregulation of MICA, and reduced Vγ2Vδ2 T cell-mediated cytotoxicity. Alternately, stimulating ATM pathway enhanced expression of MICA, and sensitized ovarian cancer cells for cytotoxic lysis by Vγ2Vδ2 T cells. We further show that combining currently approved chemotherapeutic drugs, which induced ATM signal transduction, along with Vγ2Vδ2 T cells enhanced cytotoxicity of resistant ovarian cancer cells. These findings indicate that ATM/ATR pathway plays an important role in tumor recognition, and drugs promoting ATM signaling pathway might be considered as a combination therapy together with Vγ2Vδ2 T cells for effectively treating resistant ovarian cancer cells.

  1. Lycopene inhibits Helicobacter pylori-induced ATM/ATR-dependent DNA damage response in gastric epithelial AGS cells.

    PubMed

    Jang, Sung Hee; Lim, Joo Weon; Morio, Tomohiro; Kim, Hyeyoung

    2012-02-01

    Oxidative stress linked to DNA damage is involved in the pathogenesis of Helicobacter pylori-associated gastric diseases. The DNA damage response (DDR) coordinates cell-cycle transitions, DNA repair, and apoptosis through the activation of ataxia-telangiectasia-mutated (ATM) and ATM and Rad3-related (ATR) and their target proteins. However, neither H. pylori-induced DDR nor the effects of antioxidants on the DNA damage have been established. This study aimed to investigate the detailed process of H. pylori-induced DNA damage and to examine whether lycopene, a natural antioxidant, inhibits DNA damage and cellular response of gastric epithelial AGS cells infected with H. pylori. AGS cells were cultured with H. pylori in Korean isolates and treated with or without lycopene. Cell viability, DNA damage indices, levels of 8-OH-dG, and reactive oxygen species (ROS) as well as cell-cycle distributions were determined. The activation of ATM, ATR, Chk1, and Chk2; histone H2AX focus formation; activation and induction of p53; and levels of Bax and Bcl-2 and poly(ADP-ribose) polymerase-1 (PARP-1) were assessed. The results showed that H. pylori induced apoptosis in AGS cells with increased Bax and decreased Bcl-2 expression as well as PARP-1 cleavage. Culture with H. pylori led to increases in intracellular ROS, 8-OH-dG, double-strand DNA breaks (DSBs), and DNA fragmentation. H. pylori induced activation of the ATM/Chk2 and ATR/Chk1 pathways, phosphorylation of H2AX and p53, and a delay in the progression of the cells entering the S phase. Lycopene inhibited H. pylori-induced increases in ROS, apoptosis, alterations in cell-cycle distribution, DSBs, and ATM- and ATR-mediated DDR in AGS cells. In conclusion, lycopene may be beneficial for treatment of H. pylori-induced gastric diseases associated with oxidative DNA damage.

  2. Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer

    NASA Astrophysics Data System (ADS)

    Cerqueira, M. F.; Vieira, L. G.; Alves, A.; Correia, R.; Huber, M.; Andreev, A.; Bonanni, A.; Vasilevskiy, M. I.

    2017-09-01

    This work, motivated by the technologically important task of determination of carbon dopant location in the GaN crystal lattice, employed Raman spectroscopy, with both resonant and non-resonant excitation, and infrared (IR) spectroscopy, in the attenuated total reflection (ATR) configuration, to study lattice vibration modes in a set of carbon-doped GaN (GaN:C) epilayers grown by metalorganic vapour phase epitaxy. We analyse Raman and IR-ATR spectra from the point of view of possible effects of the carbon doping, namely: (i) local vibration mode of C atoms in the nitrogen sublattice (whose frequency we theoretically estimate as 768 cm-1 using an isotope defect model), and (ii) shift in the positions of longitudinal modes owing to the phonon-plasmon coupling. We find only indirect hints of the doping effect on the resonant Raman spectra. However, we show theoretically and confirm experimentally that the IR-ATR spectroscopy can be a much more sensitive tool for this purpose, at least for the considered structures. A weak perturbation of the dielectric function of GaN:C, caused by the substitutional carbon impurity, is shown to produce a measurable dip in the ATR reflectivity spectra at  ≈770 cm-1 for both p- and s-polarizations. Moreover, it influences a specific (guided-wave type) mode observed at  ≈737 cm-1, originating from the GaN layer, which appears in the narrow frequency window where the real parts of the two components of the dielectric tensor of the hexagonal crystal have opposite signs. This interpretation is supported by our modelling of the whole multilayer structure, using a transfer matrix formalism.

  3. Reagent-free simultaneous determination of glucose and cholesterol in whole blood by FTIR-ATR

    NASA Astrophysics Data System (ADS)

    Li, Zhigang; Lv, Hong; Li, Tianhe; Si, Guangyuan; Wang, Qiaoyun; Lv, Jiangtao; Hu, Xiaofei

    2017-05-01

    Reagent-free determination of multiple analytes is an active and promising field of research in clinical analysis. In this work, the determination of glucose and cholesterol in whole blood using Fourier transform infrared (FTIR) spectroscopy equipped with an attenuated total reflectance (ATR) accessory was performed. A comprehensive sample selection rule in multi space based on SPXY was proposed, termed C-SPXY. The core idea is to make full use of different derivative spectra space to construct the calibration set which preserves the more effective information. On this basis, a partial least squares (PLS) regression fusion modeling method was also presented aiming at improving prediction accuracy of glucose and cholesterol concentration in whole blood samples. Compared with other methods based on single spectra space, the proposed fusion model based on multi spectra space C-SPXY method provides smaller RMSEP values. Experimental results demonstrate that the proposed method and model provides superior predictive power and holds a good application prospect in the field of clinical analysis.

  4. Solid acid-catalyzed cellulose hydrolysis monitored by in situ ATR-IR spectroscopy.

    PubMed

    Zakzeski, Joseph; Grisel, Ruud J H; Smit, Arjan T; Weckhuysen, Bert M

    2012-02-13

    The solid acid-catalyzed hydrolysis of cellulose was studied under elevated temperatures and autogenous pressures using in situ ATR-IR spectroscopy. Standards of cellulose and pure reaction products, which include glucose, fructose, hydroxymethylfurfural (HMF), levulinic acid (LA), formic acid, and other compounds, were measured in water under ambient and elevated temperatures. A combination of spectroscopic and HPLC analysis revealed that the cellulose hydrolysis proceeds first through the disruption of the glycosidic linkages of cellulose to form smaller cellulose molecules, which are readily observed by their distinctive C-O vibrational stretches. The continued disruption of the linkages in these oligomers eventually results in the formation and accumulation of monomeric glucose. The solid-acid catalyst accelerated the isomerization of glucose to fructose, which then rapidly reacted under hydrothermal conditions to form degradation products, which included HMF, LA, formic acid, and acetic acid. The formation of these species could be suppressed by decreasing the residence time of glucose in the reactor, reaction temperature, and contact with the metal reactor. The hydrolysis of regenerated cellulose proceeded faster and under milder conditions than microcrystalline cellulose, which resulted in increased glucose yield and selectivity.

  5. Dogfish egg case structural studies by ATR FT-IR and FT-Raman spectroscopy.

    PubMed

    Iconomidou, Vassiliki A; Georgaka, Martha E; Chryssikos, Georgios D; Gionis, Vassilis; Megalofonou, Persefoni; Hamodrakas, Stavros J

    2007-06-01

    The dogfish egg case is a composite structure that combines mechanical tensile strength, toughness and elasticity with high permeability to small molecules and ions. Presumably, it provides both a protective and a filtering role for the egg/embryo contained within it. In this work, we performed structural studies of the Galeus melastomus egg case at two different stages of the hardening process, utilizing ATR FT-IR and FT-Raman spectroscopy. Based on these data we deduce that: (a) The G. melastomus egg case, in close analogy to that of the related species Scyliorhinus cunicula, is a complex, composite structure which consists mainly of an analogue of collagen IV. This network forming protein appears to have common secondary structural characteristics in the entire egg case. (b) The outermost layer of the non-sclerotized egg case is especially rich in tyrosine, while the innermost layer is rich in polysaccharides, presumably glycosaminoglycans, and lipids. These differences are diminished upon hardening. (c) Disulfide bonds do not appear to play a significant role in cross-linking. However, cross-links involving tyrosine residues appear to sclerotize the egg case. It is proposed that the intensity of the Raman band at ca. 1615 cm(-1), which is due to ring stretching vibrations of Tyr, might be a useful indicator of the sclerotization status of a certain proteinaceous tissue, when tyrosines are involved in sclerotization mechanisms.

  6. Rapid approach to analyze biochemical variation in rat organs by ATR FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Staniszewska, Emilia; Malek, Kamilla; Baranska, Malgorzata

    2014-01-01

    ATR FTIR spectra were collected from rat tissue homogenates (myocardium, brain, liver, lung, intestine, and kidney) to analyze their biochemical content. Based on the second derivative of an average spectral profile it was possible to assign bands e.g. to triglycerides and cholesterol esters, proteins, phosphate macromolecules (DNA, RNA, phospholipids, phosphorylated proteins) and others (glycogen, lactate). Peaks in the region of 1600-1700 cm-1 related to amide I mode revealed the secondary structure of proteins. The collected spectra do not characterize morphological structure of the investigated tissues but show their different composition. The comparison of spectral information gathered from FTIR spectra of the homogenates and those obtained previously from FTIR imaging of the tissue sections implicates that the presented here approach can be successfully employed in the investigations of biochemical variation in animal tissues. Moreover, it can be used in the pharmacological and pharmacokinetic studies to correlate the overall biochemical status of the tissue with the pathological changes it has undergone.

  7. The degradation potential of PET bottles in the marine environment: An ATR-FTIR based approach

    PubMed Central

    Ioakeimidis, C.; Fotopoulou, K. N.; Karapanagioti, H. K.; Geraga, M.; Zeri, C.; Papathanassiou, E.; Galgani, F.; Papatheodorou, G.

    2016-01-01

    The dominance and persistence of plastic debris in the marine environment are well documented. No information exists in respect to their lifespan in the marine environment. Nevertheless, the degradation potential of plastic litter items remains a critical issue for marine litter research. In the present study, polyethylene terephthalate bottles (PETs) collected from the submarine environment were characterized using ATR-FTIR in respect to their degradation potential attributed to environmental conditions. A temporal indication was used as indicative to the years of presence of the PETs in the environment as debris. PETs seem to remain robust for approximately fifteen years. Afterwards, a significant decrease of the native functional groups was recorded; some even disappear; or new-not typical for PETs-are created. At a later stage, using the PET time series collected from the Saronikos Gulf (Aegean Sea–E. Mediterranean), it was possible to date bottles that were collected from the bottom of the Ionian Sea (W. Greece). It is the first time that such a study has been conducted with samples that were actually degraded in the marine environment. PMID:27000994

  8. The degradation potential of PET bottles in the marine environment: An ATR-FTIR based approach.

    PubMed

    Ioakeimidis, C; Fotopoulou, K N; Karapanagioti, H K; Geraga, M; Zeri, C; Papathanassiou, E; Galgani, F; Papatheodorou, G

    2016-03-22

    The dominance and persistence of plastic debris in the marine environment are well documented. No information exists in respect to their lifespan in the marine environment. Nevertheless, the degradation potential of plastic litter items remains a critical issue for marine litter research. In the present study, polyethylene terephthalate bottles (PETs) collected from the submarine environment were characterized using ATR-FTIR in respect to their degradation potential attributed to environmental conditions. A temporal indication was used as indicative to the years of presence of the PETs in the environment as debris. PETs seem to remain robust for approximately fifteen years. Afterwards, a significant decrease of the native functional groups was recorded; some even disappear; or new-not typical for PETs-are created. At a later stage, using the PET time series collected from the Saronikos Gulf (Aegean Sea-E. Mediterranean), it was possible to date bottles that were collected from the bottom of the Ionian Sea (W. Greece). It is the first time that such a study has been conducted with samples that were actually degraded in the marine environment.

  9. ATR-FTIR spectroscopic characterization of coexisting carbonate surface complexes on hematite

    USGS Publications Warehouse

    Bargar, J.R.; Kubicki, J.D.; Reitmeyer, R.; Davis, J.A.

    2005-01-01

    The speciation of carbonate adsorbed to hematite in air-equilibrated aqueous solutions has been studied using ATR-FTIR spectroscopy. Samples were measured over a range of pH conditions, at 0.1 M NaCl and at low ionic strength, and in H2O and D2O solutions to permit a multispecies analysis of the data. Second-derivative analyses and fits to the spectra indicate the presence of two major and two minor surface-bound carbonate species. The two major complexes coexist at near-neutral pH and low ionic strength. One of these two complexes is relatively sensitive to ionic strength, being displaced at 0.1 M NaCl, whereas the other is not. Comparison of experimental to DFT/MO-calculated frequencies suggest these two major species to be (a) a monodentate binuclear inner-sphere carbonate surface complex, and (b) a fully or partially solvated carbonate (CO32-) species that is symmetry broken and appears to reside in the structured vicinal water layers at the hematite-water interface, retained by hydrogen bonding and/or other forces. Minor carbonate complexes include diffuse layer CO32- and an unidentified inner-sphere species. Both of the dominant species observed here are likely to be significant controls of the surface charge and sorptive properties of Fe-oxides. Copyright ?? 2005 Elsevier Ltd.

  10. Attenuated Total Internal Reflectance Infrared Spectroscopy (ATR-FTIR): A Quantitative Approach for Kidney Stone Analysis

    PubMed Central

    Gulley-Stahl, Heather J.; Haas, Jennifer A.; Schmidt, Katherine A.; Evan, Andrew P.; Sommer, André J.

    2011-01-01

    The impact of kidney stone disease is significant worldwide, yet methods for quantifying stone components remain limited. A new approach requiring minimal sample preparation for the quantitative analysis of kidney stone components has been investigated utilizing attenuated total internal reflectance infrared spectroscopy (ATR-FTIR). Calcium oxalate monohydrate (COM) and hydroxylapatite (HAP), two of the most common constituents of urinary stones, were used for quantitative analysis. Calibration curves were constructed using integrated band intensities of four infrared absorptions versus concentration (weight %). The correlation coefficients of the calibration curves range from 0.997 to 0.93. The limits of detection range from 0.07 ± 0.02% COM/HAP where COM is the analyte and HAP the matrix to 0.26 ± 0.07% HAP/COM where HAP is the analyte and COM the matrix. This study shows that linear calibration curves can be generated for the quantitative analysis of stone mixtures provided the system is well understood especially with respect to particle size. PMID:19589213

  11. ATR-IR spectroscopy of pendant NH2 groups on silica involved in the Knoevenagel condensation.

    PubMed

    Wirz, Ronny; Ferri, Davide; Baiker, Alfons

    2006-04-11

    The liquid-phase Knoevenagel condensation between benzaldehyde and ethyl cyanoacetate catalyzed by aminopropyl-modified silica has been investigated using in situ attenuated total reflection infrared (ATR-IR) spectroscopy. The aim of the work was to demonstrate the different levels of information on the reaction mechanism that can be achieved by operating the spectroscopic cell in the absence and in the presence of a solvent, in flow-through and stop-flow modes and in combination with concentration modulation spectroscopy. The reaction mechanism involves the formation of an imine intermediate whose existence has been verified in situ by combining in one experiment continuous and stop-flow operations. Identical information has been gained more elegantly using concentration modulation spectroscopy, which additionally provided information on the possible origin of the solvent effect observed in the Knoevenagel reaction. Faster production and consumption of the imine intermediate was observed in cyclohexane solvent than in toluene. Identification of other species evolving on the catalyst surface and monitoring of the effluents of the spectroscopic cell provided some insight in possible catalyst deactivation.

  12. The degradation potential of PET bottles in the marine environment: An ATR-FTIR based approach

    NASA Astrophysics Data System (ADS)

    Ioakeimidis, C.; Fotopoulou, K. N.; Karapanagioti, H. K.; Geraga, M.; Zeri, C.; Papathanassiou, E.; Galgani, F.; Papatheodorou, G.

    2016-03-01

    The dominance and persistence of plastic debris in the marine environment are well documented. No information exists in respect to their lifespan in the marine environment. Nevertheless, the degradation potential of plastic litter items remains a critical issue for marine litter research. In the present study, polyethylene terephthalate bottles (PETs) collected from the submarine environment were characterized using ATR-FTIR in respect to their degradation potential attributed to environmental conditions. A temporal indication was used as indicative to the years of presence of the PETs in the environment as debris. PETs seem to remain robust for approximately fifteen years. Afterwards, a significant decrease of the native functional groups was recorded; some even disappear; or new-not typical for PETs-are created. At a later stage, using the PET time series collected from the Saronikos Gulf (Aegean Sea–E. Mediterranean), it was possible to date bottles that were collected from the bottom of the Ionian Sea (W. Greece). It is the first time that such a study has been conducted with samples that were actually degraded in the marine environment.

  13. FTIR-ATR analysis of brewed coffee: effect of roasting conditions.

    PubMed

    Lyman, Donald J; Benck, Robert; Dell, Stacy; Merle, Scott; Murray-Wijelath, Jacqueline

    2003-05-21

    FTIR-ATR was used to study the effect of roasting conditions on the flavor of brewed coffee using Guatemala Antigua coffee beans. The 1800-1680 cm(-1) carbonyl region for vinyl esters/lactones, esters, aldehydes, ketones, and acids was found to provide a flavor-print of the brewed coffee. A study of light, medium, and dark roasts indicated that when the rate of heating to the onset of the first and second cracks was kept constant, the types of carbonyl compounds formed were similar, varying only in their concentration. This difference in concentration is apparently due to the additional heating of the coffee bean beyond the second crack. When the heating rate to the onset of the first and second crack was varied, both the types and concentration of the carbonyl compounds formed during roasting were affected. Thus, heating rates of green coffee beans to the onset of the first and second cracks are important determinants of the basic taste and aroma of brewed coffee.

  14. A Stereo-Based Approach to Face Modeling for the ATR Virtual Space Conferencing System

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Agawa, Hiroshi; Nagashima, Yoshio; Kobayashi, Yukio

    1989-11-01

    The goal of this research is to generate three-dimensional facial models from facial images and to synthesize images of the models virtually viewed from different angles, which is an integral component of the ATR virtual space conferencing system project. We take a stereo-based approach. Since there is a great gap between the images and a 3D model, we argue that it is necessary to have a base face model to provide a framework. The base model is built by carefully selecting and measuring a set of points on the extremal boundaries that can be readily identified from the stereo output and another set of points inside the boundaries that can be easily determined given the boundary points. A front view and a side view of a face are employed. First the extremal boundaries are extracted or interpolated, and features such as eyes, nose and mouth are extracted. The extracted features are then matched between the two images, and their 3D positions calculated. Using these 3D data, the prepared base face model is modified to approximate the face. Finally the points on the modified 3D model are assigned intensity values derived from the original stereo images, and images are synthesized assuming new virtual viewing angles. The originality and significance of this work lies in that the system can generate a face model without a human operator's interaction with the system as in other conventional face modeling techniques.

  15. Versatile Gap Mode Plasmon under ATR Geometry towards Single Molecule Raman, Laser Trapping and Photocatalytic Reactions.

    PubMed

    Futamata, Masayuki; Akai, Keitaro; Iida, Chiaki; Akiba, Natsumi

    2017-01-01

    We have investigated various aspects of a gap mode plasmon to establish it as an analytical tool. First, markedly large (10(7) - 10(9)) enhancement factors for the Raman scattering intensity from a thiophenol (TP) monolayer sandwiched by Ag films on a prism and silver nanoparticles (AgNPs) were obtained under attenuated total reflection (ATR) geometry. Second, AgNPs with a radius of ∼20 nm were optically trapped and immobilized on TP-covered Ag films under a gap mode resonance with extremely weak laser power density of ∼1 μW/μm(2) at 532 nm. The observed optical trapping and immobilization were theoretically rationalized using a dipole-dipole coupling and van der Waals interaction between AgNPs and Ag films. Third, p-alkyl TP molecules such as p-methyl TP, p-ethyl TP, p-isopropyl TP, and p-tertiary butyl TP were photocatalytically oxidized into p-carboxyl TP, whereas o- and m-methyl TP did not show such reactions.

  16. ATR-SEIRAs characterization of surface redox processes in G. sulfurreducens.

    PubMed

    Busalmen, Juan Pablo; Esteve-Nuñez, Abraham; Berná, Antonio; Feliu, Juan Miguel

    2010-04-01

    In this work we report on the occurrence of at least two different redox pairs on the cell surface of the electrogenic bacteria Geobacter sulfurreducens adsorbed on gold that are expressed in response to the polarization potential. As previously reported on graphite (Environ. Sci. Technol. 42 (2008) 2445) a typical low potential redox pair is found centered at around -0.06 V when cells are polarized for a few hours at 0.2 V, while a new pair centered at around 0.38 V is expressed upon polarization at 0.6 V. Reversible changes in the IR band pattern of whole cells where obtained by Attenuated Total Reflection-Surface Enhanced Infrared Absorption Spectroscopy (ATR-SEIRAS) upon potential cycling around both redox pairs. Changes clearly resemble the electrochemical turnover of oxidized/reduced states in c-type cytochromes, thus evidencing the nature of the involved molecules. The expression of external cytochromes in response to the potential of the electron acceptor suggests the existence of alternative pathways of electron transport with different energy yield, though it remains to be demonstrated.

  17. Clutter performance and confuser rejection on infrared data using distortion-invariant filters for ATR

    NASA Astrophysics Data System (ADS)

    Patnaik, Rohit; Casasent, David

    2008-04-01

    We consider automatic target recognition (ATR) in infrared (IR) imagery using the minimum noise and correlation energy (MINACE) distortion-invariant filter (DIF). As in our prior work (SPIE 6566-03), we consider classification of true-class CAD targets and rejection of real clutter and unseen confuser CAD objects with range and full 360° aspect view variations. In this work, we address rejection of new UCIR bush clutter data. We also present performance scores for several different training and test cases with attention to filter capacity, i.e., the number of training images that can be included in one filter before performance on the test set deteriorates appreciably. We find that range rather than aspect view distortions seem to affect filter capacity more. Initial target contrast ratio tests are also presented. To more properly address clutter, in all tests we now form the magnitude of the output correlation plane before analysis. We also address when and why linear versus circular correlations are best. We also address DIF filter-synthesis and fast implementation for wide area "search" test regions. This introduces new issues concerning the region over which correlation plane energy is minimized in filter synthesis and the size of the FFT to use in tests. A key issue is that both training and tests should use the same procedures. This is vital for training and test metrics to be comparable. We distinguish between whether linear or circular correlation plane energy is minimized.

  18. Hierarchical searching in model-based LADAR ATR using statistical separability tests

    NASA Astrophysics Data System (ADS)

    DelMarco, Stephen; Sobel, Erik; Douglas, Joel

    2006-05-01

    In this work we investigate simultaneous object identification improvement and efficient library search for model-based object recognition applications. We develop an algorithm to provide efficient, prioritized, hierarchical searching of the object model database. A common approach to model-based object recognition chooses the object label corresponding to the best match score. However, due to corrupting effects the best match score does not always correspond to the correct object model. To address this problem, we propose a search strategy which exploits information contained in a number of representative elements of the library to drill down to a small class with high probability of containing the object. We first optimally partition the library into a hierarchic taxonomy of disjoint classes. A small number of representative elements are used to characterize each object model class. At each hierarchy level, the observed object is matched against the representative elements of each class to generate score sets. A hypothesis testing problem, using a distribution-free statistical test, is defined on the score sets and used to choose the appropriate class for a prioritized search. We conduct a probabilistic analysis of the computational cost savings, and provide a formula measuring the computational advantage of the proposed approach. We generate numerical results using match scores derived from matching highly-detailed CAD models of civilian ground vehicles used in 3-D LADAR ATR. We present numerical results showing effects on classification performance of significance level and representative element number in the score set hypothesis testing problem.

  19. ATR-FTIR spectroscopic characterization of coexisting carbonate surface complexes on hematite

    NASA Astrophysics Data System (ADS)

    Bargar, John R.; Kubicki, James D.; Reitmeyer, Rebecca; Davis, James A.

    2005-03-01

    The speciation of carbonate adsorbed to hematite in air-equilibrated aqueous solutions has been studied using ATR-FTIR spectroscopy. Samples were measured over a range of pH conditions, at 0.1 M NaCl and at low ionic strength, and in H 2O and D 2O solutions to permit a multispecies analysis of the data. Second-derivative analyses and fits to the spectra indicate the presence of two major and two minor surface-bound carbonate species. The two major complexes coexist at near-neutral pH and low ionic strength. One of these two complexes is relatively sensitive to ionic strength, being displaced at 0.1 M NaCl, whereas the other is not. Comparison of experimental to DFT/MO-calculated frequencies suggest these two major species to be (a) a monodentate binuclear inner-sphere carbonate surface complex, and (b) a fully or partially solvated carbonate (CO 32-) species that is symmetry broken and appears to reside in the structured vicinal water layers at the hematite-water interface, retained by hydrogen bonding and/or other forces. Minor carbonate complexes include diffuse layer CO 32- and an unidentified inner-sphere species. Both of the dominant species observed here are likely to be significant controls of the surface charge and sorptive properties of Fe-oxides.

  20. Rapid approach to analyze biochemical variation in rat organs by ATR FTIR spectroscopy.

    PubMed

    Staniszewska, Emilia; Malek, Kamilla; Baranska, Malgorzata

    2014-01-24

    ATR FTIR spectra were collected from rat tissue homogenates (myocardium, brain, liver, lung, intestine, and kidney) to analyze their biochemical content. Based on the second derivative of an average spectral profile it was possible to assign bands e.g. to triglycerides and cholesterol esters, proteins, phosphate macromolecules (DNA, RNA, phospholipids, phosphorylated proteins) and others (glycogen, lactate). Peaks in the region of 1600-1700 cm(-1) related to amide I mode revealed the secondary structure of proteins. The collected spectra do not characterize morphological structure of the investigated tissues but show their different composition. The comparison of spectral information gathered from FTIR spectra of the homogenates and those obtained previously from FTIR imaging of the tissue sections implicates that the presented here approach can be successfully employed in the investigations of biochemical variation in animal tissues. Moreover, it can be used in the pharmacological and pharmacokinetic studies to correlate the overall biochemical status of the tissue with the pathological changes it has undergone.