Science.gov

Sample records for improved sfr cores

  1. Uncertainty analysis of a SFR core with sodium plenum

    SciTech Connect

    Canuti, E.; Ivanov, E.; Tiberi, V.; Pignet, S.

    2012-07-01

    The new concepts of Sodium-cooled Fast Reactors have to reach the Generation IV safety objectives. In this regard the Sodium Void Effect has to be minimized for the future projects of large-size SFR as well as the uncertainties on it. The Inst. of Radiological Protection and Nuclear Safety (IRSN) as technological support of French public authorities is in charge of safety assessment of operating and under construction reactors, as well as future projects. In order to state about the safety of new SFR designs the IRSN must be able to evaluate core parameters and their uncertainties. In this frame a sensitivity and uncertainty study has been performed to evaluate the impact of nuclear data uncertainty on sodium void effect, for the benchmark model of large SFR BN-800. The benchmark parameters (effective multiplication factor and sodium void effect) have been evaluated using two codes, the deterministic code ERANOS and the Monte Carlo code SCALE, while the S/U analysis has been performed only with SCALE. The results of the these studies point out the most relevant cross section uncertainties that affect the SVE and how efforts should be done in increasing the existing nuclear data accuracies. (authors)

  2. Improving SFR Economics through Innovations from Thermal Design and Analysis Aspects

    SciTech Connect

    Haihua Zhao; Hongbin Zhang; Vincent Mousseau; Per F. Peterson

    2008-06-01

    Achieving economic competitiveness as compared to LWRs and other Generation IV (Gen-IV) reactors is one of the major requirements for large-scale investment in commercial sodium cooled fast reactor (SFR) power plants. Advances in R&D for advanced SFR fuel and structural materials provide key long-term opportunities to improve SFR economics. In addition, other new opportunities are emerging to further improve SFR economics. This paper provides an overview on potential ideas from the perspective of thermal hydraulics to improve SFR economics. These include a new hybrid loop-pool reactor design to further optimize economics, safety, and reliability of SFRs with more flexibility, a multiple reheat and intercooling helium Brayton cycle to improve plant thermal efficiency and reduce safety related overnight and operation costs, and modern multi-physics thermal analysis methods to reduce analysis uncertainties and associated requirements for over-conservatism in reactor design. This paper reviews advances in all three of these areas and their potential beneficial impacts on SFR economics.

  3. Coupled 3D-neutronics / thermal-hydraulics analysis of an unprotected loss-of-flow accident for a 3600 MWth SFR core

    SciTech Connect

    Sun, K.; Chenu, A.; Mikityuk, K.; Krepel, J.; Chawla, R.

    2012-07-01

    The core behaviour of a large (3600 MWth) sodium-cooled fast reactor (SFR) is investigated in this paper with the use of a coupled TRACE/PARCS model. The SFR neutron spectrum is characterized by several performance advantages, but also leads to one dominating neutronics drawback - a positive sodium void reactivity. This implies a positive reactivity effect when sodium coolant is removed from the core. In order to evaluate such feedback in terms of the dynamics, a representative unprotected loss-of-flow (ULOF) transient, i.e. flow run-down without SCRAM in which sodium boiling occurs, is analyzed. Although analysis of a single transient cannot allow general conclusions to be drawn, it does allow better understanding of the underlying physics and can lead to proposals for improving the core response during such an accident. The starting point of this study is the reference core design considered in the framework of the Collaborative Project on the European Sodium Fast Reactor (CP-ESFR). To reduce the void effect, the core has been modified by introducing an upper sodium plenum (along with a boron layer) and by reducing the core height-to-diameter ratio. For the ULOF considered, a sharp increase in core power results in melting of the fuel in the case of the reference core. In the modified core, a large dryout leads to melting of the clad. It seems that, for the hypothetical event considered, fuel failure cannot be avoided with just improvement of the neutronics design; therefore, thermal-hydraulics optimization has been considered. An innovative assembly design is proposed to prevent sodium vapour blocking the fuel channel. This results in preventing a downward propagation of the sodium boiling to the core center, thus limiting it to the upper region. Such a void map introduces a negative coolant density reactivity feedback, which dominates the total reactivity change. As a result, the power level and the fuel temperature are effectively reduced, and a large dryout

  4. Recent SFR calibrations and the constant SFR approximation

    NASA Astrophysics Data System (ADS)

    Cerviño, M.; Bongiovanni, A.; Hidalgo, S.

    2016-05-01

    Aims: Star formation rate (SFR) inferences are based on the so-called constant SFR approximation, where synthesis models are required to provide a calibration. We study the key points of such an approximation with the aim to produce accurate SFR inferences. Methods: We use the intrinsic algebra of synthesis models and explore how the SFR can be inferred from the integrated light without any assumption about the underlying star formation history (SFH). Results: We show that the constant SFR approximation is a simplified expression of deeper characteristics of synthesis models: It characterizes the evolution of single stellar populations (SSPs), from which the SSPs as a sensitivity curve over different measures of the SFH can be obtained. As results, we find that (1) the best age to calibrate SFR indices is the age of the observed system (i.e., about 13 Gyr for z = 0 systems); (2) constant SFR and steady-state luminosities are not required to calibrate the SFR; (3) it is not possible to define a single SFR timescale over which the recent SFH is averaged, and we suggest to use typical SFR indices (ionizing flux, UV fluxes) together with untypical ones (optical or IR fluxes) to correct the SFR for the contribution of the old component of the SFH. We show how to use galaxy colors to quote age ranges where the recent component of the SFH is stronger or softer than the older component. Conclusions: Despite of SFR calibrations are unaffected by this work, the meaning of results obtained by SFR inferences does. In our framework, results such as the correlation of SFR timescales with galaxy colors, or the sensitivity of different SFR indices to variations in the SFH, fit naturally. This framework provides a theoretical guide-line to optimize the available information from data and numerical experiments to improve the accuracy of SFR inferences.

  5. Behavior of an heterogeneous annular FBR core during an unprotected loss of flow accident: Analysis of the primary phase with SAS-SFR

    SciTech Connect

    Massara, S.; Schmitt, D.; Bretault, A.; Lemasson, D.; Darmet, G.; Verwaerde, D.; Struwe, D.; Pfrang, W.; Ponomarev, A.

    2012-07-01

    In the framework of a substantial improvement on FBR core safety connected to the development of a new Gen IV reactor type, heterogeneous core with innovative features are being carefully analyzed in France since 2009. At EDF R and D, the main goal is to understand whether a strong reduction of the Na-void worth - possibly attempting a negative value - allows a significant improvement of the core behavior during an unprotected loss of flow accident. Also, the physical behavior of such a core is of interest, before and beyond the (possible) onset of Na boiling. Hence, a cutting-edge heterogeneous design, featuring an annular shape, a Na-plena with a B{sub 4}C plate and a stepwise modulation of fissile core heights, was developed at EDF by means of the SDDS methodology, with a total Na-void worth of -1 $. The behavior of such a core during the primary phase of a severe accident, initiated by an unprotected loss of flow, is analyzed by means of the SAS-SFR code. This study is carried-out at KIT and EDF, in the framework of a scientific collaboration on innovative FBR severe accident analyses. The results show that the reduction of the Na-void worth is very effective, but is not sufficient alone to avoid Na-boiling and, hence, to prevent the core from entering into the primary phase of a severe accident. Nevertheless, the grace time up to boiling onset is greatly enhanced in comparison to a more traditional homogeneous core design, and only an extremely low fraction of the fuel (<0.1%) enters into melting at the end of this phase. A sensitivity analysis shows that, due to the inherent neutronic characteristics of such a core, the gagging scheme plays a major role on the core behavior: indeed, an improved 4-zones gagging scheme, associated with an enhanced control rod drive line expansion feed-back effect, finally prevents the core from entering into sodium boiling. This major conclusion highlights both the progress already accomplished and the need for more detailed

  6. On the use of moderating material to enhance the feedback coefficients in SFR cores with high minor actinide content

    SciTech Connect

    Merk, B.; Weiss, F. P.

    2012-07-01

    The use of fine distributed moderating material to enhance the feedback effects and to reduce the sodium void effecting sodium cooled fast reactor cores is described. The influence of the moderating material on the neutron spectrum, the power distribution, and the burnup distribution is shown. The consequences of the use of fine distributed moderating material into fuel assemblies with fuel configurations foreseen for minor actinide transmutation is analyzed and the transmutation efficiency is compared. The degradation of the feedback effects due to the insertion of minor actinides and the compensation by the use of moderating materials is discussed. (authors)

  7. IMF, SFR and stellar depletion in the local Galactic plane, based on improved Hipparcos samples of single stars

    NASA Astrophysics Data System (ADS)

    Dawson, S. A.; Schröder, K.-P.

    2010-05-01

    We have used the recently reduced Hipparcos data and the Washington Double Star catalogue to derive two volume- and magnitude-limited samples of single stars in the Galactic plane. The star count method has been used to compare synthetic to empirical samples of stars within both the main sequence and the evolved regions of the Hertzsprung-Russell diagram. Corrections have been made for unrecognized binaries and the residual incompleteness of the Hipparcos catalogue. Two methods of binary reduction have been compared, a flat 71 per cent binary fraction (including multiples) and a mass-dependent binary fraction, which decreases with primary mass from 71 to 57 per cent. A semi-empirical relation between the vertical scaleheight and stellar age has been derived from kinematic data provided by the OSACA data base. This relation is used to prescribe the loss of stellar content vertically from the plane due to heating. When employing the fixed binary ratio, we find that the best fit is provided by a Scalo initial mass function (IMF) with an exponent of 1.85 +/- 0.15, together with an average Galactic thin-disc star formation rate (SFR) of 618(+/-15) starsMyr-1kpc-3 with 1211(+/-30)MsolarMyr-1kpc-3 for single stars with M* > 0.9Msolar. The application of the mass-dependent variable binary ratio yields more single stars at lower mass and hence a steeper (Γ = 2.2,..., 2.3) IMF and an increased SFR.

  8. Trade-off study on the power capacity of a prototype SFR in Korea

    SciTech Connect

    Baek, M. H.; Kim, S. J.; Yoo, J.; Bae, I. H.

    2012-07-01

    The major roles of a prototype SFR are to provide irradiation test capability for the fuel and structure materials, and to obtain operational experiences of systems. Due to a compromise between the irradiation capability and construction costs, the power level should be properly determined. In this paper, a trade-off study on the power level of the prototype SFR was performed from a neutronics viewpoint. To select candidate cores, the parametric study of pin diameters was estimated using 20 wt.% uranium fuel. The candidate cores of different power levels, 125 MWt, 250 MWt, 400 MWt, and 500 MWt, were compared with the 1500 MWt reference core. The resulting core performance and economic efficiency indices became insensitive to the power at about 400-500 MWt and sharply deteriorated at about 125-250 MWt with decreasing core sizes. Fuel management scheme, TRU core performance comparing with uranium core, and sodium void reactivity were also evaluated with increasing power levels. It is found that increasing the number of batches showed higher burnup performance and economic efficiency. However, increasing the cycle length showed the trends in lower economic efficiency. Irradiation performance of TRU and enriched TRU cores was improved about 20 % and 50 %, respectively. The maximum sodium void reactivity of 5.2$ was confirmed less than the design limit of 7.5$. As a result, the power capacity of the prototype SFR should not be less than 250 MWt and would be appropriate at {approx} 500 MWt considering the performance and economic efficiency. (authors)

  9. Generation of SFR few-group constants using the Monte Carlo code Serpent

    SciTech Connect

    Fridman, E.; Rachamin, R.; Shwageraus, E.

    2013-07-01

    In this study, the Serpent Monte Carlo code was used as a tool for preparation of homogenized few-group cross sections for the nodal diffusion analysis of Sodium cooled Fast Reactor (SFR) cores. Few-group constants for two reference SFR cores were generated by Serpent and then employed by nodal diffusion code DYN3D in 2D full core calculations. The DYN3D results were verified against the references full core Serpent Monte Carlo solutions. A good agreement between the reference Monte Carlo and nodal diffusion results was observed demonstrating the feasibility of using Serpent for generation of few-group constants for the deterministic SFR analysis. (authors)

  10. Improved Thermoplastic/Iron-Particle Transformer Cores

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A.; Bryant, Robert G.; Namkung, Min

    2004-01-01

    A method of fabricating improved transformer cores from composites of thermoplastic matrices and iron-particles has been invented. Relative to commercially available laminated-iron-alloy transformer cores, the cores fabricated by this method weigh less and are less expensive. Relative to prior polymer-matrix/ iron-particle composite-material transformer cores, the cores fabricated by this method can be made mechanically stronger and more magnetically permeable. In addition, whereas some prior cores have exhibited significant eddy-current losses, the cores fabricated by this method exhibit very small eddy-current losses. The cores made by this method can be expected to be attractive for use in diverse applications, including high-signal-to-noise transformers, stepping motors, and high-frequency ignition coils. The present method is a product of an experimental study of the relationships among fabrication conditions, final densities of iron particles, and mechanical and electromagnetic properties of fabricated cores. Among the fabrication conditions investigated were molding pressures (83, 104, and 131 MPa), and molding temperatures (250, 300, and 350 C). Each block of core material was made by uniaxial-compression molding, at the applicable pressure/temperature combination, of a mixture of 2 weight percent of LaRC (or equivalent high-temperature soluble thermoplastic adhesive) with 98 weight percent of approximately spherical iron particles having diameters in the micron range. Each molded block was cut into square cross-section rods that were used as core specimens in mechanical and electromagnetic tests. Some of the core specimens were annealed at 900 C and cooled slowly before testing. For comparison, a low-carbon-steel core was also tested. The results of the tests showed that density, hardness, and rupture strength generally increased with molding pressure and temperature, though the correlation was rather weak. The weakness of the correlation was attributed to

  11. R and D program for core instrumentation improvements devoted for French sodium fast reactors

    SciTech Connect

    Jeannot, J. P.; Rodriguez, G.; Jammes, C.; Bernardin, B.; Portier, J. L.; Jadot, F.; Maire, S.; Verrier, D.; Loisy, F.; Prele, G.

    2011-07-01

    Under the framework of French R and D studies for Generation IV reactors and more specifically for sodium-cooled fast reactors (SFR); the CEA, EDF and AREVA have launched a joint coordinated research programme. This paper deals with the R and D sets out to achieve better inspection, maintenance, availability and decommissioning. In particular the instrumentation requirements for core monitoring and detection in the case of accidental events. Requirements mainly involve diversifying the means of protection and improving instrumentation performance in terms of responsiveness and sensitivity. Operation feedback from the Phenix and Superphenix prototype reactors and studies, carried out within the scope of the EFR projects, has been used to define the needs for instrumentation enhancement. (authors)

  12. Nuclear data uncertainty propagation for neutronic key parameters of CEA's SFR V2B and CFV sodium fast reactor designs

    SciTech Connect

    Archier, P.; Buiron, L.; De Saint Jean, C.; Dos Santos, N.

    2012-07-01

    This paper presents a nuclear data uncertainty propagation analysis for two CEA's Sodium-cooled Fast Reactor designs: the SFR V2B and CFV cores. The nuclear data covariance matrices are provided by the DER/SPRC/LEPh's nuclear data team (see companion paper) for several major isotopes. From the current status of this analysis, improvements on certain nuclear data reactions are highlighted as well as the need for new specific integral experiments in order to meet the technological breakthroughs proposed by the CFV core. (authors)

  13. Core skills assessment to improve mathematical competency

    NASA Astrophysics Data System (ADS)

    Carr, Michael; Bowe, Brian; Fhloinn, Eabhnat Ní

    2013-12-01

    Many engineering undergraduates begin third-level education with significant deficiencies in their core mathematical skills. Every year, in the Dublin Institute of Technology, a diagnostic test is given to incoming first-year students, consistently revealing problems in basic mathematics. It is difficult to motivate students to address these problems; instead, they struggle through their degree, carrying a serious handicap of poor core mathematical skills, as confirmed by exploratory testing of final year students. In order to improve these skills, a pilot project was set up in which a 'module' in core mathematics was developed. The course material was basic, but 90% or higher was required to pass. Students were allowed to repeat this module throughout the year by completing an automated examination on WebCT populated by a question bank. Subsequent to the success of this pilot with third-year mechanical engineering students, the project was extended to five different engineering programmes, across three different year-groups. Full results and analysis of this project are presented, including responses to interviews carried out with a selection of the students involved.

  14. Improving Core Strength to Prevent Injury

    ERIC Educational Resources Information Center

    Oliver, Gretchen D.; Adams-Blair, Heather R.

    2010-01-01

    Regardless of the sport or skill, it is essential to have correct biomechanical positioning, or postural control, in order to maximize energy transfer. Correct postural control requires a strong, stable core. A strong and stable core allows one to transfer energy effectively as well as reduce undue stress. An unstable or weak core, on the other…

  15. RISK-INFORMED BALANCING OF SAFETY, NONPROLIFERATION, AND ECONOMICS FOR THE SFR

    SciTech Connect

    Apostolakis, George; Driscoll, Michael; Golay, Michael; Kadak, Andrew; Todreas, Neil; Aldmir, Tunc; Denning, Richard; Lineberry, Michael

    2011-10-20

    , particularly concerning seismic and aircraft impactrelated risks. Most importantly, within the context of the TNF historical SFR safety concerns about energetic core disruptive accidents are seen to be unimportant, but those of rare scenarios mentioned above are seen to be of dominant concern. In terms of proliferation risks the SFR energy system is seen not to be of considerably greater concern than with other nuclear power technologies, providing that highly effective safeguards are employed. We find the economic performance of proposed SFRs likely, due to the problems of using sodium as a coolant, to be inferior to those of LWRs unless they can be credited for services to improve nuclear waste disposal, nuclear fuel utilization and proliferation risk reductions. None of the design innovations investigated offers the promise to reverse this conclusion. The most promising innovation investigated is that of improving the plant's thermodynamic efficiency via use of the supercritical CO{sub 2} (rather than steam Rankine) power conversion system. We were unable to reach conclusions about the economic and proliferation risk implications of competing nuclear fuel processing methods, as available designs are too little developed to justify any such results. Overall, we find the SFR to be a promising alternative to LWRs should the conditions governing the valuation change substantially from current ones.

  16. Core Skills Assessment to Improve Mathematical Competency

    ERIC Educational Resources Information Center

    Carr, Michael; Bowe, Brian; Ní Fhloinn, Eabhnat

    2013-01-01

    Many engineering undergraduates begin third-level education with significant deficiencies in their core mathematical skills. Every year, in the Dublin Institute of Technology, a diagnostic test is given to incoming first-year students, consistently revealing problems in basic mathematics. It is difficult to motivate students to address these…

  17. Fast reactor core concepts to improve transmutation efficiency

    SciTech Connect

    Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

    2015-12-31

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

  18. On the [CII]-SFR Relation in High Redshift Galaxies

    NASA Astrophysics Data System (ADS)

    Vallini, L.; Gallerani, S.; Ferrara, A.; Pallottini, A.; Yue, B.

    2015-11-01

    After two Atacama Large Millimeter/submillimeter Array (ALMA) observing cycles, only a handful of [C ii] 158 μm emission line searches in z > 6 galaxies have reported a positive detection, questioning the applicability of the local [C ii]-star formation rate (SFR) relation to high-z systems. To investigate this issue we use the Vallini et al. (V13) model,based on high-resolution, radiative transfer cosmological simulations to predict the [C ii] emission from the interstellar medium of a z ≈ 7 (halo mass Mh = 1.17 × 1011 M⊙) galaxy. We improve the V13 model by including (a) a physically motivated metallicity (Z) distribution of the gas, (b) the contribution of photodissociation regions (PDRs), and (c) the effects of cosmic microwave background (CMB) on the [C ii] line luminosity. We study the relative contribution of diffuse neutral gas to the total [C ii] emission (Fdiff/Ftot) for different SFR and Z values. We find that the [C ii] emission arises predominantly from PDRs: regardless of the galaxy properties, Fdiff/Ftot ≤ 10%, since at these early epochs the CMB temperature approaches the spin temperature of the [C ii] transition in the cold neutral medium (TCMB ˜ {T}s{{CNM}} ˜ 20 K). Our model predicts a high-z [C ii]-SFR relation, consistent with observations of local dwarf galaxies (0.02 < Z/Z⊙ < 0.5). The [C ii] deficit suggested by actual data (LCii < 2.0 × 107 L⊙ in BDF3299 at z ≈ 7.1) if confirmed by deeper ALMA observations, can be ascribed to negative stellar feedback disrupting molecular clouds around star formation sites. The deviation from the local [C ii]-SFR would then imply a modified Kennicutt-Schmidt relation in z > 6 galaxies. Alternatively/in addition, the deficit might be explained by low gas metallicities (Z < 0.1 Z⊙).

  19. Rotary Mode Core Sample System availability improvement

    SciTech Connect

    Jenkins, W.W.; Bennett, K.L.; Potter, J.D.; Cross, B.T.; Burkes, J.M.; Rogers, A.C.

    1995-02-28

    The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2.

  20. Mold with improved core for metal casting operation

    DOEpatents

    Gritzner, Verne B.; Hackett, Donald W.

    1977-01-01

    The present invention is directed to a mold containing an improved core for use in casting hollow, metallic articles. The core is formed of, or covered with, a layer of cellular material which possesses sufficient strength to maintain its structural integrity during casting, but will crush to alleviate the internal stresses that build up if the normal contraction during solidification and cooling is restricted.

  1. Improving Engine Efficiency Through Core Developments

    NASA Technical Reports Server (NTRS)

    Heidmann, James D.

    2011-01-01

    The NASA Environmentally Responsible Aviation (ERA) Project and Fundamental Aeronautics Projects are supporting compressor and turbine research with the goal of reducing aircraft engine fuel burn and greenhouse gas emissions. The primary goals of this work are to increase aircraft propulsion system fuel efficiency for a given mission by increasing the overall pressure ratio (OPR) of the engine while maintaining or improving aerodynamic efficiency of these components. An additional area of work involves reducing the amount of cooling air required to cool the turbine blades while increasing the turbine inlet temperature. This is complicated by the fact that the cooling air is becoming hotter due to the increases in OPR. Various methods are being investigated to achieve these goals, ranging from improved compressor three-dimensional blade designs to improved turbine cooling hole shapes and methods. Finally, a complementary effort in improving the accuracy, range, and speed of computational fluid mechanics (CFD) methods is proceeding to better capture the physical mechanisms underlying all these problems, for the purpose of improving understanding and future designs.

  2. Improvements in Fabrication of Sand/Binder Cores for Casting

    NASA Technical Reports Server (NTRS)

    Bakhitiyarov, Sayavur I.; Overfelt, Ruel A.; Adanur, Sabit

    2005-01-01

    Three improvements have been devised for the cold-box process, which is a special molding process used to make sand/binder cores for casting hollow metal parts. These improvements are: The use of fiber-reinforced composite binder materials (in contradistinction to the non-fiber-reinforced binders used heretofore), The substitution of a directed-vortex core-blowing subprocess for a prior core-blowing process that involved a movable gassing plate, and The use of filters made from filtration-grade fabrics to prevent clogging of vents. For reasons that exceed the scope of this article, most foundries have adopted the cold-box process for making cores for casting metals. However, this process is not widely known outside the metal-casting industry; therefore, a description of pertinent aspects of the cold-box process is prerequisite to a meaningful description of the aforementioned improvements. In the cold-box process as practiced heretofore, sand is first mixed with a phenolic resin (considered to be part 1 of a three-part binder) and an isocyanate resin (part 2 of the binder). Then by use of compressed air, the mixture is blown into a core box, which is a mold for forming the core. Next, an amine gas (part 3 of the binder) that acts as a catalyst for polymerization of parts 1 and 2 is blown through the core box. Alternatively, a liquid amine that vaporizes during polymerization can be incorporated into the sand/resin mixture. Once polymerization is complete, the amine gas is purged from the core box by use of compressed air. The finished core is then removed from the core box.

  3. Innovative power conversion system for the French SFR prototype, ASTRID

    SciTech Connect

    Cachon, L.; Biscarrat, C.; Morin, F.; Haubensack, D.; Rigal, E.; Moro, I.; Baque, F.; Madeleine, S.; Rodriguez, G.; Laffont, G.

    2012-07-01

    In the framework of the French Act of 28 June 2006 about nuclear materials and waste management, the prototype ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration), foreseen in operation by the 20's, will have to demonstrate not only the minor actinide transmutation capability, but also the progress made in Sodium Fast Reactor (SFR) technology on an industrial scale, by qualifying innovative options. Some of these options still require improvements, especially in the field of operability and safety. In fact, one of the main issues with the standard steam/water Power Conversion System (PCS) of SFR is the fast and energetic chemical reaction between water and sodium, which could occur in steam generators in case of tube failure. To manage the sodium/water reaction, one way consists in minimizing the impact of such event: hence studies are carried out on steam generator design, improvement of the physical knowledge of this phenomenon, development of numerical simulation to predict the reaction onset and consequences, and associated detection improvement. On the other hand, the other way consists in eliminating sodium/water reaction. In this frame, the CEA contribution to the feasibility evaluation of an alternative innovative PCS (replacing steam/water by 180 bar pressurised nitrogen) is focused on the following main topics: - The parametric study leading to nitrogen selection: the thermodynamic cycle efficiency optimisation on Brayton cycles is performed with several gases at different pressures. - The design of innovative compact heat exchangers for the gas loop: here the key points are the nuclear codification associated with inspection capability, the innovative welding process and the thermal-hydraulic and thermal-mechanic optimisations. After a general introduction of the ASTRID project, this paper presents in detail these different feasibility studies being led on the innovative gas PCS for an SFR. (authors)

  4. Reengineering a surgical service line: focusing on core process improvement.

    PubMed

    Kelly, D L; Pestotnik, S L; Coons, M C; Lelis, J W

    1997-01-01

    Integrating principles from a variety of theory has led to the development of a conceptual framework for reengineering in a clinical care delivery setting to improve the value of services provided to the customer. A conceptual framework involving the identification of three high level core processes to reengineer can provide clarity and focus for clinicians to begin directing reengineering efforts. Those core processes are: clinical management of the patient's medical needs, patient operational processes to support the clinical processes, and administrative decision-making processes to support the implementation of the clinical and operational processes. Improvement in any one of these areas has the potential to increase value, but the concurrent targeting of these core processes for reengineering has provided a synergy that has accelerated the achievement of the desired outcomes in the area of surgical services. PMID:9161059

  5. Dense Cores in The Pipe Nebula: An Improved Core Mass Function

    NASA Astrophysics Data System (ADS)

    Rathborne, J. M.; Lada, C. J.; Muench, A. A.; Alves, J. F.; Kainulainen, J.; Lombardi, M.

    2009-07-01

    In this paper, we derive an improved core mass function (CMF) for the Pipe Nebula from a detailed comparison between measurements of visual extinction and molecular-line emission. We have compiled a refined sample of 201 dense cores toward the Pipe Nebula using a two-dimensional threshold identification algorithm informed by recent simulations of dense core populations. Measurements of radial velocities using complimentary C18O (1-0) observations enable us to cull out from this sample those 43 extinction peaks that are either not associated with dense gas or are not physically associated with the Pipe Nebula. Moreover, we use the derived C18O central velocities to differentiate between single cores with internal structure and blends of two or more physically distinct cores, superposed along the same line of sight. We then are able to produce a more robust dense core sample for future follow-up studies and a more reliable CMF than was possible previously. We confirm earlier indications that the CMF for the Pipe Nebula departs from a single power-law-like form with a break or knee at M ~ 2.7 ± 1.3 M sun. Moreover, we also confirm that the CMF exhibits a similar shape to the stellar initial mass function (IMF), but is scaled to higher masses by a factor of ~4.5. We interpret this difference in scaling to be a measure of the star formation efficiency (22% ± 8%). This supports earlier suggestions that the stellar IMF may originate more or less directly from the CMF.

  6. Improved cryogenic coring device for sampling wetland soils

    SciTech Connect

    Cahoon, D.R.; Lynch, J.C.; Knaus, R.M.

    1996-09-01

    This paper is the third in a series on the design and construction (Knaus 1986) and improvements (Knaus and Cahoon 1990) of a cryogenic soil-coring device (cryocorer). Freezing wetland soils in place during sampling eliminates compaction, dewatering, and loss of flocculent material at the water-sediment interface. The cryocorer is suitable for sampling soils of emergent marsh and mangrove forests as well as shallow water bottoms, although it has been used primarily for the former. A small-diameter frozen soil core minimizes disruption of the surface, can be evaluated immediately for overall quality, and can be used to measure soil profiles and subsample for further analysis. The cryocorer continues to be used in studies of wetland accretion and soil bulk density throughout the US. Concomitant with the increased use of the device, improvements in cryocorer design and application have occurred. Reported here are improvements in design that have been made since 1992 with references to wetland research in which the cryocorer has been used extensively.

  7. Rapid core measure improvement through a "business case for quality".

    PubMed

    Perlin, Jonathan B; Horner, Stephen J; Englebright, Jane D; Bracken, Richard M

    2014-01-01

    Incentives to improve performance are emerging as revenue or financial penalties are linked to the measured quality of service provided. The HCA "Getting to Green" program was designed to rapidly increase core measure performance scores. Program components included (1) the "business case for quality"-increased awareness of how quality drives financial performance; (2) continuous communication of clinical and financial performance data; and (3) evidence-based clinical protocols, incentives, and tools for process improvement. Improvement was measured by comparing systemwide rates of adherence to national quality measures for heart failure (HF), acute myocardial infarction (AMI), pneumonia (PN), and surgical care (SCIP) to rates from all facilities reporting to the Centers for Medicare and Medicaid Services (CMS). As of the second quarter of 2011, 70% of HCA total measure set composite scores were at or above the 90th percentile of CMS scores. A test of differences in regression coefficients between the CMS national average and the HCA average revealed significant differences for AMI (p = .001), HF (p = .012), PN (p < .001), and SCIP (p = .015). This program demonstrated that presentation of the financial implications of quality, transparency in performance data, and clearly defined goals could cultivate the desire to use improvement tools and resources to raise performance.

  8. An Innovative Hybrid Loop-Pool SFR Design and Safety Analysis Methods: Today and Tomorrow

    SciTech Connect

    Hongbin Zhang; Haihua Zhao; Vincent Mousseau

    2008-04-01

    Investment in commercial sodium cooled fast reactor (SFR) power plants will become possible only if SFRs achieve economic competitiveness as compared to light water reactors and other Generation IV reactors. Toward that end, we have launched efforts to improve the economics and safety of SFRs from the thermal design and safety analyses perspectives at Idaho National Laboratory. From the thermal design perspective, an innovative hybrid loop-pool SFR design has been proposed. This design takes advantage of the inherent safety of a pool design and the compactness of a loop design to further improve economics and safety. From the safety analyses perspective, we have initiated an effort to develop a high fidelity reactor system safety code.

  9. Core symptoms of autism improved after vitamin D supplementation.

    PubMed

    Jia, Feiyong; Wang, Bing; Shan, Ling; Xu, Zhida; Staal, Wouter G; Du, Lin

    2015-01-01

    Autism spectrum disorder (ASD) is a common neurodevelopmental disorder caused by a complex interaction between genetic and environmental risk factors. Among the environmental factors, vitamin D3 (cholecaliferol) seems to play a significant role in the etiology of ASD because this vitamin is important for brain development. Lower concentrations of vitamin D3 may lead to increased brain size, altered brain shape, and enlarged ventricles, which have been observed in patients with ASD. Vitamin D3 is converted into 25-hydroxyvitamin D3 in the liver. Higher serum concentrations of this steroid may reduce the risk of autism. Importantly, children with ASD are at an increased risk of vitamin D deficiency, possibly due to environmental factors. It has also been suggested that vitamin D3 deficiency may cause ASD symptoms. Here, we report on a 32-month-old boy with ASD and vitamin D3 deficiency. His core symptoms of autism improved significantly after vitamin D3 supplementation. This case suggests that vitamin D3 may play an important role in the etiology of ASD, stressing the importance of clinical assessment of vitamin D3 deficiency and the need for vitamin D3 supplementation in case of deficiency. PMID:25511123

  10. Core symptoms of autism improved after vitamin D supplementation.

    PubMed

    Jia, Feiyong; Wang, Bing; Shan, Ling; Xu, Zhida; Staal, Wouter G; Du, Lin

    2015-01-01

    Autism spectrum disorder (ASD) is a common neurodevelopmental disorder caused by a complex interaction between genetic and environmental risk factors. Among the environmental factors, vitamin D3 (cholecaliferol) seems to play a significant role in the etiology of ASD because this vitamin is important for brain development. Lower concentrations of vitamin D3 may lead to increased brain size, altered brain shape, and enlarged ventricles, which have been observed in patients with ASD. Vitamin D3 is converted into 25-hydroxyvitamin D3 in the liver. Higher serum concentrations of this steroid may reduce the risk of autism. Importantly, children with ASD are at an increased risk of vitamin D deficiency, possibly due to environmental factors. It has also been suggested that vitamin D3 deficiency may cause ASD symptoms. Here, we report on a 32-month-old boy with ASD and vitamin D3 deficiency. His core symptoms of autism improved significantly after vitamin D3 supplementation. This case suggests that vitamin D3 may play an important role in the etiology of ASD, stressing the importance of clinical assessment of vitamin D3 deficiency and the need for vitamin D3 supplementation in case of deficiency.

  11. Documentation of the Streamflow-Routing (SFR2) Package to Include Unsaturated Flow Beneath Streams - A Modification to SFR1

    USGS Publications Warehouse

    Niswonger, Richard G.; Prudic, David E.

    2005-01-01

    Many streams in the United States, especially those in semiarid regions, have reaches that are hydraulically disconnected from underlying aquifers. Ground-water withdrawals have decreased water levels in valley aquifers beneath streams, increasing the occurrence of disconnected streams and aquifers. The U.S. Geological Survey modular ground-water model (MODFLOW-2000) can be used to model these interactions using the Streamflow-Routing (SFR1) Package. However, the approach does not consider unsaturated flow between streams and aquifers and may not give realistic results in areas with significantly deep unsaturated zones. This documentation describes a method for extending the capabilities of MODFLOW-2000 by incorporating the ability to simulate unsaturated flow beneath streams. A kinematic-wave approximation to Richards' equation was solved by the method of characteristics to simulate unsaturated flow beneath streams in SFR1. This new package, called SFR2, includes all the capabilities of SFR1 and is designed to be used with MODFLOW-2000. Unlike SFR1, seepage loss from the stream may be restricted by the hydraulic conductivity of the unsaturated zone. Unsaturated flow is simulated independently of saturated flow within each model cell corresponding to a stream reach whenever the water table (head in MODFLOW) is below the elevation of the streambed. The relation between unsaturated hydraulic conductivity and water content is defined by the Brooks-Corey function. Unsaturated flow variables specified in SFR2 include saturated and initial water contents; saturated vertical hydraulic conductivity; and the Brooks-Corey exponent. These variables are defined independently for each stream reach. Unsaturated flow in SFR2 was compared to the U.S. Geological Survey's Variably Saturated Two-Dimensional Flow and Transport (VS2DT) Model for two test simulations. For both test simulations, results of the two models were in good agreement with respect to the magnitude and downward

  12. An empirical SFR estimator for high redshift galaxies:

    NASA Astrophysics Data System (ADS)

    Arnouts, Stephane

    2015-08-01

    At high redshift, most of the SFR indicators are limited to the most massive galaxies (Far-IR, radio) and out of reach of optical spectroscopy (Halpha). The UV continuum is the only one available at all redshifts and for galaxies within a large range of mass. The main question is then to properly account for dust absorption. The SED fitting are always limited in the choice of popular attenuation laws (if not only one, starburst) which relies on the slope of the UV continuum. The alternative is to measure the net budget between the absorbed vs un-absorbed UV light i.e. the infrared excess (IRX= Lir/Luv).By using the deep 24 micron in the COSMOS field, we have observed a remarkable behaviour of IRX stripes within the (NUV-r)o vs (r-K)o color diagram which can be used to derive robust SFR estimates just with the Luv, Lr and Lk luminosities (Arnouts et al, 2013). We have shown that we can explain the correlation if we consider a two component models for the birth clouds and the ISM and also a complete model for galaxy inclination to explain the extrem IRX values. We are now extended the method with Herschel data at higher redshift (z~2) and lower masses (M~10^8Mo) by using stacking techniques and find that the IRX-NUVrK correlation persists (Le Floc’h , in prep). This method allows us to derive an accurate SFR for each individual galaxy based on its location in the NUVrK diagram and with no assumption on dust attenuation law, a main caveat for SED fitting technique.We investigated the behavior of the scatter of the SFR-Mass in GOODS and COSMOS fields and find that both SFR (Lir+Luv) or SFR(NUVrK) estimatesare consistent (Ilbert et al., 2015). Finally will investigate the dust-free UV luminosity functions in between 0SFR densities down to 10^8-8.5 Mo, with no resort to stacking technique as in Far-IR or radio wavelength.

  13. Enhanced oil recovery. Improved reservoir evaluation object of sponge coring process

    SciTech Connect

    Mickey, V.

    1981-04-01

    Oil saturation data determined by core analysis have improved. One result is the development of the sponge coring process. In the sponge coring method, the core sample is taken in much the same way as in conventional coring. The major difference is the porous, hard sponge that lines the core barrel. The sponge is so porous (approximately 80%) that cigarette smoke can be blown through it. It has one full darcy permeability and is oil-wet. The sponge is inside a thin polyvinyl chloride liner with small perforations in it. As the sponge core barrel is run into the hole, the sponge becomes wet with drilling fluid, usually water. Any oil in the core being forced out by the water and the reduction in pressure as the core is brought to surface is caught by the sponge. Since it is oil-wet the oil is retained. But water is forced out the small perforations in the liner. At the surface the 20-ft core is cut into 5-ft sections and put into special containers filled with fluid from the formation. That keeps the core in standard condition. Even much of the gas in solution remains in the core. This is noted during capping operations as the cap is forced back until the glue on it holds and seals the tube.

  14. Verification and validation plan for the SFR system analysis module

    SciTech Connect

    Hu, R.

    2014-12-18

    This report documents the Verification and Validation (V&V) Plan for software verification and validation of the SFR System Analysis Module (SAM), developed at Argonne National Laboratory for sodium fast reactor whole-plant transient analysis. SAM is developed under the DOE NEAMS program and is part of the Reactor Product Line toolkit. The SAM code, the phenomena and computational models of interest, the software quality assurance, and the verification and validation requirements and plans are discussed in this report.

  15. Electrical Core Transformer for Grid Improvement Incorporating Wire Magnetic Components

    SciTech Connect

    Harrie R. Buswell, PhD; Dennis Jacobs, PhD; Steve Meng

    2012-03-26

    The research reported herein adds to the understanding of oil-immersed distribution transformers by exploring and demonstrating potential improvements in efficiency and cost utilizing the unique Buswell approach wherein the unit is redesigned, replacing magnetic sheet with wire allowing for improvements in configuration and increased simplicity in the build process. Exploration of new designs is a critical component in our drive to assure reduction of energy waste, adequate delivery to the citizenry, and the robustness of U.S. manufacturing. By moving that conversation forward, this exploration adds greatly to our base of knowledge and clearly outlines an important avenue for further exploration. This final report shows several advantages of this new transformer type (outlined in a report signed by all of our collaborating partners and included in this document). Although materials development is required to achieve commercial potential, the clear benefits of the technology if that development were a given is established. Exploration of new transformer types and further work on the Buswell design approach is in the best interest of the public, industry, and the United States. Public benefits accrue from design alternatives that reduce the overall use of energy, but it must be acknowledged that new DOE energy efficiency standards have provided some assurance in that regard. Nonetheless the burden of achieving these new standards has been largely shifted to the manufacturers of oil-immersed distribution transformers with cost increasing up to 20% of some units versus 2006 when this investigation was started. Further, rising costs have forced the industry to look closely are far more expensive technologies which may threaten U.S. competitiveness in the distribution transformer market. This concern is coupled with the realization that many units in the nation's grid are beyond their optimal life which suggests that the nation may be headed for an infrastructure crisis

  16. Pre-conceptual design study of ASTRID core

    SciTech Connect

    Varaine, F.; Marsault, P.; Chenaud, M. S.; Bernardin, B.; Conti, A.; Sciora, P.; Venard, C.; Fontaine, B.; Devictor, N.; Martin, L.; Scholer, A. C.; Verrier, D.

    2012-07-01

    In the framework of the ASTRID project at CEA, core design studies are performed at CEA with the AREVA and EDF support. At the stage of the project, pre-conceptual design studies are conducted in accordance with GEN IV reactors criteria, in particularly for safety improvements. An improved safety for a sodium cooled reactor requires revisiting many aspects of the design and is a rather lengthy process in current design approach. Two types of cores are under evaluation, one classical derived from the SFR V2B and one more challenging called CFV (low void effect core) with a large gain on the sodium void effect. The SFR V2b core have the following specifications: a very low burn-up reactivity swing (due to a small cycle reactivity loss) and a reduced sodium void effect with regard to past designs such as the EFR (around 2$ minus). Its performances are an average burn-up of 100 GWd/t, and an internal conversion ratio equal to one given a very good behavior of this core during a control rod withdrawal transient). The CFV with its specific design offers a negative sodium void worth while maintaining core performances. In accordance of ASTRID needs for demonstration those cores are 1500 MWth power (600 MWe). This paper will focus on the CFV pre-conceptual design of the core and S/A, and the performances in terms of safety will be evaluated on different transient scenario like ULOF, in order to assess its intrinsic behavior compared to a more classical design like V2B core. The gap in term of margin to a severe accident due to a loss of flow initiator underlines the potential capability of this type of core to enhance prevention of severe accident in accordance to safety demonstration. (authors)

  17. Mapping QTLs for improving grain yield using the USDA rice mini-core collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yield is the most important and complex trait for genetic improvement in crops, and marker-assisted selection enhances the improvement efficiency. The USDA rice mini-core collection derived from over 18,000 accessions of global origins is an ideal panel for association mapping. We phenotyped 203 O. ...

  18. Modified Y-TZP core design improves all-ceramic crown reliability.

    PubMed

    Silva, N R F A; Bonfante, E A; Rafferty, B T; Zavanelli, R A; Rekow, E D; Thompson, V P; Coelho, P G

    2011-01-01

    This study tested the hypothesis that all-ceramic core-veneer system crown reliability is improved by modification of the core design. We modeled a tooth preparation by reducing the height of proximal walls by 1.5 mm and the occlusal surface by 2.0 mm. The CAD-based tooth preparation was replicated and positioned in a dental articulator for core and veneer fabrication. Standard (0.5 mm uniform thickness) and modified (2.5 mm height lingual and proximal cervical areas) core designs were produced, followed by the application of veneer porcelain for a total thickness of 1.5 mm. The crowns were cemented to 30-day-aged composite dies and were either single-load-to-failure or step-stress-accelerated fatigue-tested. Use of level probability plots showed significantly higher reliability for the modified core design group. The fatigue fracture modes were veneer chipping not exposing the core for the standard group, and exposing the veneer core interface for the modified group.

  19. Improvements to an Electrical Engineering Skill Audit Exam to Improve Student Mastery of Core EE Concepts

    ERIC Educational Resources Information Center

    Parent, D. W.

    2011-01-01

    The San Jose State University Electrical Engineering (EE) Department implemented a skill audit exam for graduating seniors in 1999 with the purpose of assessing the teaching and the students' mastery of core concepts in EE. However, consistent low scores for the first years in which the test was administered suggested that students had little…

  20. Measuring the reduced scattering coefficient and γ with SFR spectroscopy: studying the phase function dependence (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Post, Anouk L.; Zhang, Xu; Bosschaart, Nienke; Van Leeuwen, Ton G.; Sterenborg, Henricus J. C. M.; Faber, Dirk J.

    2016-03-01

    Both Optical Coherence Tomography (OCT) and Single Fiber Reflectance Spectroscopy (SFR) are used to determine various optical properties of tissue. We developed a method combining these two techniques to measure the scattering anisotropy (g1) and γ (=1-g2/1-g1), related to the 1st and 2nd order moments of the phase function. The phase function is intimately associated with the cellular organization and ultrastructure of tissue, physical parameters that may change during disease onset and progression. Quantification of these parameters may therefore allow for improved non-invasive, in vivo discrimination between healthy and diseased tissue. With SFR the reduced scattering coefficient and γ can be extracted from the reflectance spectrum (Kanick et al., Biomedical Optics Express 2(6), 2011). With OCT the scattering coefficient can be extracted from the signal as a function of depth (Faber et al., Optics Express 12(19), 2004). Consequently, by combining SFR and OCT measurements at the same wavelengths, the scattering anisotropy (g) can be resolved using µs'= µs*(1-g). We performed measurements on a suspension of silica spheres as a proof of principle. The SFR model for the reflectance as a function of the reduced scattering coefficient and γ is based on semi-empirical modelling. These models feature Monte-Carlo (MC) based model constants. The validity of these constants - and thus the accuracy of the estimated parameters - depends on the phase function employed in the MC simulations. Since the phase function is not known when measuring in tissue, we will investigate the influence of assuming an incorrect phase function on the accuracy of the derived parameters.

  1. Core-shell TiO2 microsphere with enhanced photocatalytic activity and improved lithium storage

    NASA Astrophysics Data System (ADS)

    Guo, Hong; Tian, Dongxue; Liu, Lixiang; Wang, Yapeng; Guo, Yuan; Yang, Xiangjun

    2013-05-01

    Inorganic hollow core-shell spheres have attracted considerable interest due to their singular properties and wide range of potential applications. Herein a novel facile generic strategy of combining template assisted and solvothermal alcoholysis is employed to prepare core-void-shell anatase TiO2 nanoparticle aggregates with an excellent photocatalytic activity, and enhanced lithium storage in large quantities. Amorphous carbon can be loaded on the TiO2 nanoparticles uniformly under a suitably formulated ethanol/water system in the solvothermal alcoholysis process, and the subsequent calcination results of the formation of core-shell-shell anatase TiO2 nanoparticle aggregates. The intrinsic core-void-shell nature as well as high porosity of the unique nanostructures contributes greatly to the superior photocatalytic activity and improved performance as anode materials for lithium ion batteries.

  2. A New Streamflow-Routing (SFR1) Package to Simulate Stream-Aquifer Interaction with MODFLOW-2000

    USGS Publications Warehouse

    Prudic, David E.; Konikow, Leonard F.; Banta, Edward R.

    2004-01-01

    The increasing concern for water and its quality require improved methods to evaluate the interaction between streams and aquifers and the strong influence that streams can have on the flow and transport of contaminants through many aquifers. For this reason, a new Streamflow-Routing (SFR1) Package was written for use with the U.S. Geological Survey's MODFLOW-2000 ground-water flow model. The SFR1 Package is linked to the Lake (LAK3) Package, and both have been integrated with the Ground-Water Transport (GWT) Process of MODFLOW-2000 (MODFLOW-GWT). SFR1 replaces the previous Stream (STR1) Package, with the most important difference being that stream depth is computed at the midpoint of each reach instead of at the beginning of each reach, as was done in the original Stream Package. This approach allows for the addition and subtraction of water from runoff, precipitation, and evapotranspiration within each reach. Because the SFR1 Package computes stream depth differently than that for the original package, a different name was used to distinguish it from the original Stream (STR1) Package. The SFR1 Package has five options for simulating stream depth and four options for computing diversions from a stream. The options for computing stream depth are: a specified value; Manning's equation (using a wide rectangular channel or an eight-point cross section); a power equation; or a table of values that relate flow to depth and width. Each stream segment can have a different option. Outflow from lakes can be computed using the same options. Because the wetted perimeter is computed for the eight-point cross section and width is computed for the power equation and table of values, the streambed conductance term no longer needs to be calculated externally whenever the area of streambed changes as a function of flow. The concentration of solute is computed in a stream network when MODFLOW-GWT is used in conjunction with the SFR1 Package. The concentration of a solute in a

  3. Improvement of open and semi-open core wall system in tall buildings by closing of the core section in the last story

    NASA Astrophysics Data System (ADS)

    Kheyroddin, A.; Abdollahzadeh, D.; Mastali, M.

    2014-09-01

    Increasing number of tall buildings in urban population caused development of tall building structures. One of the main lateral load resistant systems is core wall system in high-rise buildings. Core wall system has two important behavioral aspects where the first aspect is related to reduce the lateral displacement by the core bending resistance and the second is governed by increasing of the torsional resistance and core warping of buildings. In this study, the effects of closed section core in the last story have been considered on the behavior of models. Regarding this, all analyses were performed by ETABS 9.2.v software (Wilson and Habibullah). Considering (a) drift and rotation of the core over height of buildings, (b) total and warping stress in the core body, (c) shear in beams due to warping stress, (d) effect of closing last story on period of models in various modes, (e) relative displacement between walls in the core system and (f) site effects in far and near field of fault by UBC97 spectra on base shear coefficient showed that the bimoment in open core is negative in the last quarter of building and it is similar to wall-frame structures. Furthermore, analytical results revealed that closed section core in the last story improves behavior of the last quarter of structure height, since closing of core section in the last story does not have significant effect on reducing base shear value in near and far field of active faults.

  4. Summary of South Fence Road phase II 1993 field operations at Site SFR-4

    SciTech Connect

    Foutz, W.L.; McCord, J.P.

    1996-05-01

    This report is a basic data report for field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-4P and SFR-4T. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.

  5. Summary of South Fence Road phase II 1993 field operations at site SFR-3

    SciTech Connect

    Foutz, W.L.; McCord, J.P.

    1996-05-01

    This report is a basic data report fro field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-3P and SFR-3T. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.

  6. Sodium fast reactor evaluation: Core materials

    NASA Astrophysics Data System (ADS)

    Cheon, Jin Sik; Lee, Chan Bock; Lee, Byoung Oon; Raison, J. P.; Mizuno, T.; Delage, F.; Carmack, J.

    2009-07-01

    In the framework of the Generation IV Sodium Fast Reactor (SFR) Program the Advanced Fuel Project has conducted an evaluation of the available fuel systems supporting future sodium cooled fast reactors. In this paper the status of available and developmental materials for SFR core cladding and duct applications is reviewed. To satisfy the Generation IV SFR fuel requirements, an advanced cladding needs to be developed. The candidate cladding materials are austenitic steels, ferritic/martensitic (F/M) steels, and oxide dispersion strengthened (ODS) steels. A large amount of irradiation testing is required, and the compatibility of cladding with TRU-loaded fuel at high temperatures and high burnup must be investigated. The more promising F/M steels (compared to HT9) might be able to meet the dose requirements of over 200 dpa for ducts in the GEN-IV SFR systems.

  7. Identification of SFR6, a key component in cold acclimation acting post-translationally on CBF function.

    PubMed

    Knight, Heather; Mugford, Sarah G; Ulker, Bekir; Gao, Dahai; Thorlby, Glenn; Knight, Marc R

    2009-04-01

    The sfr6-1 mutant of Arabidopsis thaliana was identified previously on the basis of its failure to undergo acclimation to freezing temperatures following exposure to low positive temperatures. This failure is attributed to a defect in the pathway leading to cold on-regulated (COR) gene expression via CBF (C-box binding factor) transcription factors. We identified a region of chromosome 4 containing SFR6 by positional mapping. Fine mapping of the sfr6-1 mutation proved impossible as the locus resides very close to the centromere. Therefore, we screened 380 T-DNA lines with insertions in genes within the large region to which sfr6-1 mapped. This resulted in the identification of two further mutant alleles of SFR6 (sfr6-2 and sfr6-3); like the original sfr6-1 mutation, these disrupt freezing tolerance and COR gene expression. To determine the protein sequence, we cloned an SFR6 cDNA based on the predicted coding sequence, but this offered no indication as to the mechanism by which SFR6 acts. The SFR6 gene itself is not strongly regulated by cold, thus discounting regulation of SFR6 activity at the transcriptional level. We show that over-expression of CBF1 or CBF2 transcription factors, which constitutively activate COR genes in the wild-type, cannot do so in sfr6-1. We demonstrate that CBF protein accumulates to wild-type levels in response to cold in sfr6-1. These results indicate a role for the SFR6 protein in the CBF pathway -downstream of CBF translation. The fact that the SFR6 protein is targeted to the nucleus may suggest a direct role in modulating gene expression.

  8. MSFR TRU-burning potential and comparison with an SFR

    SciTech Connect

    Fiorina, C.; Cammi, A.; Franceschini, F.; Krepel, J.

    2013-07-01

    The objective of this work is to evaluate the Molten Salt Fast Reactor (MSFR) potential benefits in terms of transuranics (TRU) burning through a comparative analysis with a sodium-cooled FR. The comparison is based on TRU- and MA-burning rates, as well as on the in-core evolution of radiotoxicity and decay heat. Solubility issues limit the TRU-burning rate to 1/3 that achievable in traditional low-CR FRs (low-Conversion-Ratio Fast Reactors). The softer spectrum also determines notable radiotoxicity and decay heat of the equilibrium actinide inventory. On the other hand, the liquid fuel suggests the possibility of using a Pu-free feed composed only of Th and MA (Minor Actinides), thus maximizing the MA burning rate. This is generally not possible in traditional low-CR FRs due to safety deterioration and decay heat of reprocessed fuel. In addition, the high specific power and the lack of out-of-core cooling times foster a quick transition toward equilibrium, which improves the MSFR capability to burn an initial fissile loading, and makes the MSFR a promising system for a quick (i.e., in a reactor lifetime) transition from the current U-based fuel cycle to a novel closed Th cycle. (authors)

  9. Core Team Members' Impact on Outcomes and Process Improvement in the Initial Resuscitation of Trauma Patients.

    PubMed

    Geyer, Rebecca; Kilgore, Jane; Chow, Stuart; Grant, Courtney; Gibson, Alissa; Rice, Megan

    2016-01-01

    Genesis Trauma Center is an American College of Surgeons-The Committee on Trauma-verified Level III facility located in Southeastern Ohio. Process improvement and patient safety showed inconsistencies in trauma documentation and comfort level of the nursing staff. In February 2014, Genesis implemented a trauma nurse leader program to provide a core team of trauma nurses for the initial resuscitation. The overall goal of implementing a trauma nurse leader (TNL) program was to focus education on a core team, providing an increased level of skill of experience to oversee trauma patient care. The TNL program has shown promise in the pilot phase by decreasing emergency department length of stay and improving trauma documentation.

  10. Core Team Members' Impact on Outcomes and Process Improvement in the Initial Resuscitation of Trauma Patients.

    PubMed

    Geyer, Rebecca; Kilgore, Jane; Chow, Stuart; Grant, Courtney; Gibson, Alissa; Rice, Megan

    2016-01-01

    Genesis Trauma Center is an American College of Surgeons-The Committee on Trauma-verified Level III facility located in Southeastern Ohio. Process improvement and patient safety showed inconsistencies in trauma documentation and comfort level of the nursing staff. In February 2014, Genesis implemented a trauma nurse leader program to provide a core team of trauma nurses for the initial resuscitation. The overall goal of implementing a trauma nurse leader (TNL) program was to focus education on a core team, providing an increased level of skill of experience to oversee trauma patient care. The TNL program has shown promise in the pilot phase by decreasing emergency department length of stay and improving trauma documentation. PMID:26953536

  11. Use of Solid Hydride Fuel for Improved long-Life LWR Core Designs

    SciTech Connect

    Greenspan, E

    2006-04-30

    The primary objective of this project was to assess the feasibility of improving the performance of PWR and BWR cores by using solid hydride fuels instead of the commonly used oxide fuel. The primary measure of performance considered is the bus-bar cost of electricity (COE). Additional performance measures considered are safety, fuel bundle design simplicity – in particular for BWR’s, and plutonium incineration capability. It was found that hydride fuel can safely operate in PWR’s and BWR’s without restricting the linear heat generation rate of these reactors relative to that attainable with oxide fuel. A couple of promising applications of hydride fuel in PWR’s and BWR’s were identified: (1) Eliminating dedicated water moderator volumes in BWR cores thus enabling to significantly increase the cooled fuel rods surface area as well as the coolant flow cross section area in a given volume fuel bundle while significantly reducing the heterogeneity of BWR fuel bundles thus achieving flatter pin-by-pin power distribution. The net result is a possibility to significantly increase the core power density – on the order of 30% and, possibly, more, while greatly simplifying the fuel bundle design. Implementation of the above modifications is, though, not straightforward; it requires a design of completely different control system that could probably be implemented only in newly designed plants. It also requires increasing the coolant pressure drop across the core. (2) Recycling plutonium in PWR’s more effectively than is possible with oxide fuel by virtue of a couple of unique features of hydride fuel – reduced inventory of U-238 and increased inventory of hydrogen. As a result, the hydride fuelled core achieves nearly double the average discharge burnup and the fraction of the loaded Pu it incinerates in one pass is double that of the MOX fuel. The fissile fraction of the Pu in the discharged hydride fuel is only ~2/3 that of the MOX fuel and the

  12. Optimization of a heterogeneous fast breeder reactor core with improved behavior during unprotected transients

    SciTech Connect

    Poumerouly, S.; Schmitt, D.; Massara, S.; Maliverney, B.

    2012-07-01

    Innovative Sodium-cooled Fast Reactors (SFRs) are currently being investigated by CEA, AREVA and EDF in the framework of a joint French collaboration, and the construction of a GEN IV prototype, ASTRID (Advanced Sodium Technical Reactor for Industrial Demonstration), is scheduled in the years 2020. Significant improvements are expected so as to improve the reactor safety: the goal is to achieve a robust safety demonstration of the mastering of the consequences of a Core Disruptive Accident (CDA), whether by means of prevention or mitigation features. In this framework, an innovative design was proposed by CEA in 2010. It aims at strongly reducing the sodium void effect, thereby improving the core behavior during unprotected loss of coolant transients. This design is strongly heterogeneous and includes, amongst others, a fertile plate, a sodium plenum associated with a B{sub 4}C upper blanket and a stepwise modulation of the fissile height of the core (onwards referred to as the 'diabolo shape'). In this paper, studies which were entirely carried out at EDF are presented: the full potential of this heterogeneous concept is thoroughly investigated using the SDDS methodology. (authors)

  13. Operation and performance of the Supercritical Fluids Reactor (SFR)

    SciTech Connect

    Hanush, R.G.; Rice, S.F.; Hunter, T.B.; Aiken, J.D.

    1995-11-01

    The Supercritical Fluids Reactor (SFR) at Sandia National Laboratories, CA has been developed to examine and solve engineering, process, and fundamental chemistry issues regarding the development of supercritical water oxidation (SCWO). This report details the experimental apparatus, procedures, analytical methods used in these experiments, and performance characteristics of the reactor. The apparatus consists of pressurization, feed, preheat, reactor, cool down, and separation subsystems with ancillary control and data acquisition hardware and software. Its operating range is from 375 - 650{degrees} at 3250 - 6300 psi with resident times from 0.09 to 250 seconds. Procedures required for experimental operations are described. They include maintenance procedures conducted between experiments, optical alignment for acquisition of spectroscopic data, setup of the experiment, reactor start up, experimental operations, and shutdown of apparatus. Analytical methods used are Total Organic Carbon analysis, Gas Chromatography, ion probes, pH probes, turbidity measurements and in situ Raman spectroscopy. Experiments conducted that verify the accuracy of measurement and sampling methods are described.

  14. Development of a core drug list towards improving prescribing education and reducing errors in the UK

    PubMed Central

    Baker, Emma; Pryce Roberts, Adele; Wilde, Kirsty; Walton, Hannah; Suri, Sati; Rull, Gurvinder; Webb, Andrew

    2011-01-01

    AIM To develop a core list of 100 commonly prescribed drugs to support prescribing education. METHODS A retrospective analysis of prescribing data from primary care in England (2006 and 2008) and from two London Teaching Hospitals (2007 and 2009) was performed. A survey of prescribing by foundation year 1 (FY1) doctors in 39 NHS Trusts across London was carried out. RESULTS A core list of 100 commonly prescribed drugs comprising ≥0.1% prescriptions in primary and/or secondary care was developed in 2006/7. The core list remained stable over 2 years. FY1 doctors prescribed 65% drugs on the list at least monthly. Seventy-six% of FY1 doctors did not regularly prescribe any drugs not on the core list. There was a strong correlation between prescribing frequency (prescriptions for each drug class expressed as percentage of all prescriptions written) and error rate described in the EQUIP study (errors made when prescribing each drug class expressed as a percentage of all errors made), n= 39, r= 0.861, P= 0.000. CONCLUSIONS Our core drug list identifies drugs that are commonly used and associated with error and is stable over at least 2 years. This list can now be used to develop learning resources and training programmes to improve prescribing of drugs in regular use. Complementary skills required for prescribing less familiar drugs must be developed in parallel. Ongoing research is required to monitor the effect of new training initiatives on prescribing error and patient safety. PMID:21219399

  15. Pre-Stressing Micron-Scale Aluminum Core-Shell Particles to Improve Reactivity

    NASA Astrophysics Data System (ADS)

    Levitas, Valery I.; McCollum, Jena; Pantoya, Michelle

    2015-01-01

    The main direction in increasing reactivity of aluminum (Al) particles for energetic applications is reduction in their size down to nanoscale. However, Al nanoparticles are 30-50 times more expensive than micron scale particles and possess safety and environmental issues. Here, we improved reactivity of Al micron scale particles by synthesizing pre-stressed core-shell structures. Al particles were annealed and quenched to induce compressive stresses in the alumina passivation shell surrounding Al core. This thermal treatment was designed based on predictions of the melt-dispersion mechanism (MDM); a theory describing Al particle reaction under high heating rate. For all anneal treatment temperatures, experimental flame propagation rates for Al combined with nanoscale copper oxide (CuO) are in quantitative agreement with the theoretical predictions based on the MDM. The best treatment increases flame rate by 36% and achieves 68% of that for the best Al nanoparticles.

  16. Pre-Stressing Micron-Scale Aluminum Core-Shell Particles to Improve Reactivity

    PubMed Central

    Levitas, Valery I.; McCollum, Jena; Pantoya, Michelle

    2015-01-01

    The main direction in increasing reactivity of aluminum (Al) particles for energetic applications is reduction in their size down to nanoscale. However, Al nanoparticles are 30–50 times more expensive than micron scale particles and possess safety and environmental issues. Here, we improved reactivity of Al micron scale particles by synthesizing pre-stressed core-shell structures. Al particles were annealed and quenched to induce compressive stresses in the alumina passivation shell surrounding Al core. This thermal treatment was designed based on predictions of the melt-dispersion mechanism (MDM); a theory describing Al particle reaction under high heating rate. For all anneal treatment temperatures, experimental flame propagation rates for Al combined with nanoscale copper oxide (CuO) are in quantitative agreement with the theoretical predictions based on the MDM. The best treatment increases flame rate by 36% and achieves 68% of that for the best Al nanoparticles. PMID:25597747

  17. 50 CFR 86.93 - Where should I use the SFR logo?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.93 Where should I use the SFR logo?...

  18. 50 CFR 86.92 - Who can use the SFR logo?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.92 Who can use the SFR logo? The...

  19. 50 CFR 86.93 - Where should I use the SFR logo?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.93 Where should I use the SFR logo?...

  20. 50 CFR 86.93 - Where should I use the SFR logo?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.93 Where should I use the SFR logo?...

  1. 50 CFR 86.92 - Who can use the SFR logo?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE AND SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.92 Who can use the SFR...

  2. 50 CFR 86.92 - Who can use the SFR logo?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.92 Who can use the SFR logo? The...

  3. 50 CFR 86.92 - Who can use the SFR logo?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.92 Who can use the SFR logo? The...

  4. 50 CFR 86.92 - Who can use the SFR logo?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE AND SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG) PROGRAM State Use of Signs and Sport Fish Restoration Symbols § 86.92 Who can use the SFR...

  5. A CORE approach to progress monitoring and feedback: Enhancing evidence and improving practice.

    PubMed

    Barkham, Michael; Mellor-Clark, John; Stiles, William B

    2015-12-01

    This article describes the Clinical Outcomes in Routine Evaluation (CORE) System and reports on its scientific yield and practice impact. First, we describe the suite of CORE measures, including the centerpiece CORE-Outcome Measure (CORE-OM), its short forms, special purpose forms, translations, and psychometric properties, along with the pretreatment CORE Therapy Assessment Form and the CORE End of Therapy Form. Second, we provide an overview of the scientific yield arising from analyses of large CORE data sets collected in routine practice. Third, we describe the use of CORE measures for feedback in practice settings. Finally, we consider future directions for monitoring and feedback in research and practice.

  6. Combining SIP and NMR Measurements to Develop Improved Estimates of Permeability in Sandstone Cores

    NASA Astrophysics Data System (ADS)

    Keating, K.; Binley, A. M.

    2013-12-01

    Permeability is traditionally measured in-situ by inducing groundwater flow using pumping, slug, or packer tests; however, these methods require the existence of wells, can be labor intensive and can be constrained by measurement support volumes. Indirect estimates of permeability based on geophysical techniques benefit from relatively short measurement times, do not require fluid extraction, and are non-invasive when made from the surface (or minimally invasive when made in a borehole). However, estimates of permeability based on a single geophysical method often require calibration for rock type, and cannot be used to uniquely determine all of the physical properties required to accurately determine permeability. In this laboratory study we present the first critical step towards developing a method for estimating permeability based on the synergistic coupling of two complementary geophysical methods: spectral induced polarization (SIP) and nuclear magnetic resonance (NMR). To develop an improved model for estimating permeability, laboratory SIP and NMR measurements were collected on a series of sandstone cores, covering a wide range of permeabilities. Current models for estimating permeability from each individual geophysical measurement were compared to independently obtained estimates of permeability. The comparison confirmed previous research showing that estimates from SIP or NMR alone only yield the permeability within order of magnitude accuracy and must be calibrated for rock type. Next, the geophysical parameters determined from SIP and NMR were compared to independent measurements the physical properties of the sandstone cores including gravimetric porosity and pores-size distributions (obtained from mercury injection porosimetry); this comparison was used to evaluate which geophysical parameter more consistently and accurately predicted each physical property. Finally, we present an improved method for estimating permeability in sandstone cores based

  7. Bi-content Gadolinia as Burnable Absorber in PWR to Improve the Reactor Core Behaviour

    SciTech Connect

    Zheng, S.

    2007-07-01

    The gadolinia product is one of the standard burnable absorbers used in the PWR long and low leakage fuel cycle in order to control the radial power distribution and to hold down the initial core reactivity. This product presents a large number of advantages such as the high efficiency with only a small number of gadolinia-bearing rods, the easy adjustment between the number and the content of the gadolinia-bearing rods according to the cycle length need and the initial reactivity hold-down, no increasing of boron concentration versus cycle depletion, no additional increasing of internal pressure in poisoned rods, very low additional manufacture cost. On the other hand, some unfavourable phenomena are also observed during the utilization of the gadolinia: amplification of the asymmetrical power distribution and more negative axial offset. Based on the correlation between the gadolinia burnout and its content, the use of gadolinia bi-content will improve the parameters indicated here above. The gadolinia bi-content have been used in BWR for more than 20 years. In this paper, the comparison of the main reactor core physical parameters in PWR, calculated with the AREVA NP standard neutronic code package SCIENCE, is made by using the mono- and bi-content of the gadolinia products in the same fuel assembly. The results show that the asymmetrical axial and azimuthal power distribution can be improved in the case of the bi-content gadolinia product. (authors)

  8. GAMA/H-ATLAS: a meta-analysis of SFR indicators - comprehensive measures of the SFR-M* relation and cosmic star formation history at z < 0.4

    NASA Astrophysics Data System (ADS)

    Davies, L. J. M.; Driver, S. P.; Robotham, A. S. G.; Grootes, M. W.; Popescu, C. C.; Tuffs, R. J.; Hopkins, A.; Alpaslan, M.; Andrews, S. K.; Bland-Hawthorn, J.; Bremer, M. N.; Brough, S.; Brown, M. J. I.; Cluver, M. E.; Croom, S.; da Cunha, E.; Dunne, L.; Lara-López, M. A.; Liske, J.; Loveday, J.; Moffett, A. J.; Owers, M.; Phillipps, S.; Sansom, A. E.; Taylor, E. N.; Michalowski, M. J.; Ibar, E.; Smith, M.; Bourne, N.

    2016-09-01

    We present a meta-analysis of star formation rate (SFR) indicators in the Galaxy And Mass Assembly (GAMA) survey, producing 12 different SFR metrics and determining the SFR-M* relation for each. We compare and contrast published methods to extract the SFR from each indicator, using a well-defined local sample of morphologically selected spiral galaxies, which excludes sources which potentially have large recent changes to their SFR. The different methods are found to yield SFR-M* relations with inconsistent slopes and normalizations, suggesting differences between calibration methods. The recovered SFR-M* relations also have a large range in scatter which, as SFRs of the targets may be considered constant over the different time-scales, suggests differences in the accuracy by which methods correct for attenuation in individual targets. We then recalibrate all SFR indicators to provide new, robust and consistent luminosity-to-SFR calibrations, finding that the most consistent slopes and normalizations of the SFR-M* relations are obtained when recalibrated using the radiation transfer method of Popescu et al. These new calibrations can be used to directly compare SFRs across different observations, epochs and galaxy populations. We then apply our calibrations to the GAMA II equatorial data set and explore the evolution of star formation in the local Universe. We determine the evolution of the normalization to the SFR-M* relation from 0 < z < 0.35 - finding consistent trends with previous estimates at 0.3 < z < 1.2. We then provide the definitive z < 0.35 cosmic star formation history, SFR-M* relation and its evolution over the last 3 billion years.

  9. Unexpected improvement in core autism spectrum disorder symptoms after long-term treatment with probiotics

    PubMed Central

    Grossi, Enzo; Melli, Sara; Dunca, Delia; Terruzzi, Vittorio

    2016-01-01

    Objectives: Autism spectrum disorder is a neurodevelopmental condition that typically displays socio-communicative impairment as well as restricted stereotyped interests and activities, in which gastrointestinal disturbances are commonly reported. We report the case of a boy with Autism Spectrum Disorder (ASD) diagnosis, severe cognitive disability and celiac disease in which an unexpected improvement of autistic core symptoms was observed after four months of probiotic treatment. Method: The case study refers to a 12 years old boy with ASD and severe cognitive disability attending the Villa Santa Maria Institute in resident care since 2009. Diagnosis of ASDs according to DSM-V criteria was confirmed by ADOS-2 assessment (Autism Diagnostic Observation Schedule). The medication used was VSL#3, a multi-strain mixture of ten probiotics. The treatment lasted 4 weeks followed by a four month follow-up. The rehabilitation program and the diet was maintained stable in the treatment period and in the follow up. ADOS-2 was assessed six times: two times before starting treatment; two times during the treatment and two times after interruption of the treatment. Results: The probiotic treatment reduced the severity of abdominal symptoms as expected but an improvement in Autistic core symptoms was unexpectedly clinically evident already after few weeks from probiotic treatment start. The score of Social Affect domain of ADOS improved changing from 20 to 18 after two months treatment with a further reduction of 1 point in the following two months. The level 17 of severity remained stable in the follow up period. It is well known that ADOS score does not fluctuate spontaneously along time in ASD and is absolutely stable. Conclusions: The appropriate use of probiotics deserves further research, which hopefully will open new avenues in the fight against ASD.

  10. Unexpected improvement in core autism spectrum disorder symptoms after long-term treatment with probiotics

    PubMed Central

    Grossi, Enzo; Melli, Sara; Dunca, Delia; Terruzzi, Vittorio

    2016-01-01

    Objectives: Autism spectrum disorder is a neurodevelopmental condition that typically displays socio-communicative impairment as well as restricted stereotyped interests and activities, in which gastrointestinal disturbances are commonly reported. We report the case of a boy with Autism Spectrum Disorder (ASD) diagnosis, severe cognitive disability and celiac disease in which an unexpected improvement of autistic core symptoms was observed after four months of probiotic treatment. Method: The case study refers to a 12 years old boy with ASD and severe cognitive disability attending the Villa Santa Maria Institute in resident care since 2009. Diagnosis of ASDs according to DSM-V criteria was confirmed by ADOS-2 assessment (Autism Diagnostic Observation Schedule). The medication used was VSL#3, a multi-strain mixture of ten probiotics. The treatment lasted 4 weeks followed by a four month follow-up. The rehabilitation program and the diet was maintained stable in the treatment period and in the follow up. ADOS-2 was assessed six times: two times before starting treatment; two times during the treatment and two times after interruption of the treatment. Results: The probiotic treatment reduced the severity of abdominal symptoms as expected but an improvement in Autistic core symptoms was unexpectedly clinically evident already after few weeks from probiotic treatment start. The score of Social Affect domain of ADOS improved changing from 20 to 18 after two months treatment with a further reduction of 1 point in the following two months. The level 17 of severity remained stable in the follow up period. It is well known that ADOS score does not fluctuate spontaneously along time in ASD and is absolutely stable. Conclusions: The appropriate use of probiotics deserves further research, which hopefully will open new avenues in the fight against ASD. PMID:27621806

  11. Six Weeks of Core Stability Training Improves Landing Kinetics Among Female Capoeira Athletes: A Pilot Study

    PubMed Central

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-01-01

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6

  12. Six weeks of core stability training improves landing kinetics among female capoeira athletes: a pilot study.

    PubMed

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-03-29

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6

  13. Modifications to WRF's dynamical core to improve the treatment of moisture for large-eddy simulations

    NASA Astrophysics Data System (ADS)

    Xiao, Heng; Endo, Satoshi; Wong, May; Skamarock, William C.; Klemp, Joseph B.; Fast, Jerome D.; Gustafson, William I.; Vogelmann, Andrew M.; Wang, Hailong; Liu, Yangang; Lin, Wuyin

    2015-12-01

    Yamaguchi and Feingold (2012) note that the cloud fields in their large-eddy simulations (LESs) of marine stratocumulus using the Weather Research and Forecasting (WRF) model exhibit a strong sensitivity to time stepping choices. In this study, we reproduce and analyze this sensitivity issue using two stratocumulus cases, one marine and one continental. Results show that (1) the sensitivity is associated with spurious motions near the moisture jump between the boundary layer and the free atmosphere, and (2) these spurious motions appear to arise from neglecting small variations in water vapor mixing ratio (qv) in the pressure gradient calculation in the acoustic substepping portion of the integration procedure. We show that this issue is remedied in the WRF dynamical core by replacing the prognostic equation for the potential temperature θ with one for the moist potential temperature θm=θ(1 + 1.61qv), which allows consistent treatment of moisture in the calculation of pressure during the acoustic substeps. With this modification, the spurious motions and the sensitivity to the time stepping settings (i.e., the dynamic time step length and number of acoustic sub-steps) are eliminated in both of the example stratocumulus cases. This modification improves the applicability of WRF for LES applications, and possibly other models using similar dynamical core formulations, and also permits the use of longer time steps than in the original code.

  14. Modifications to WRFs dynamical core to improve the treatment of moisture for large-eddy simulations

    DOE PAGES

    Xiao, Heng; Endo, Satoshi; Wong, May; Skamarock, William C.; Klemp, Joseph B.; Fast, Jerome D.; Gustafson, Jr., William I.; Vogelmann, Andrew; Wang, Hailong; Liu, Yangang; et al

    2015-10-29

    Yamaguchi and Feingold (2012) note that the cloud fields in their large-eddy simulations (LESs) of marine stratocumulus using the Weather Research and Forecasting (WRF) model exhibit a strong sensitivity to time stepping choices. In this study, we reproduce and analyze this sensitivity issue using two stratocumulus cases, one marine and one continental. Results show that (1) the sensitivity is associated with spurious motions near the moisture jump between the boundary layer and the free atmosphere, and (2) these spurious motions appear to arise from neglecting small variations in water vapor mixing ratio (qv) in the pressure gradient calculation in themore » acoustic sub-stepping portion of the integration procedure. We show that this issue is remedied in the WRF dynamical core by replacing the prognostic equation for the potential temperature θ with one for the moist potential temperature θm=θ(1+1.61qv), which allows consistent treatment of moisture in the calculation of pressure during the acoustic sub-steps. With this modification, the spurious motions and the sensitivity to the time stepping settings (i.e., the dynamic time step length and number of acoustic sub-steps) are eliminated in both of the example stratocumulus cases. In conclusion, this modification improves the applicability of WRF for LES applications, and possibly other models using similar dynamical core formulations, and also permits the use of longer time steps than in the original code.« less

  15. Modifications to WRFs dynamical core to improve the treatment of moisture for large-eddy simulations

    SciTech Connect

    Xiao, Heng; Endo, Satoshi; Wong, May; Skamarock, William C.; Klemp, Joseph B.; Fast, Jerome D.; Gustafson, Jr., William I.; Vogelmann, Andrew; Wang, Hailong; Liu, Yangang; Lin, Wuyin

    2015-10-29

    Yamaguchi and Feingold (2012) note that the cloud fields in their large-eddy simulations (LESs) of marine stratocumulus using the Weather Research and Forecasting (WRF) model exhibit a strong sensitivity to time stepping choices. In this study, we reproduce and analyze this sensitivity issue using two stratocumulus cases, one marine and one continental. Results show that (1) the sensitivity is associated with spurious motions near the moisture jump between the boundary layer and the free atmosphere, and (2) these spurious motions appear to arise from neglecting small variations in water vapor mixing ratio (qv) in the pressure gradient calculation in the acoustic sub-stepping portion of the integration procedure. We show that this issue is remedied in the WRF dynamical core by replacing the prognostic equation for the potential temperature θ with one for the moist potential temperature θm=θ(1+1.61qv), which allows consistent treatment of moisture in the calculation of pressure during the acoustic sub-steps. With this modification, the spurious motions and the sensitivity to the time stepping settings (i.e., the dynamic time step length and number of acoustic sub-steps) are eliminated in both of the example stratocumulus cases. In conclusion, this modification improves the applicability of WRF for LES applications, and possibly other models using similar dynamical core formulations, and also permits the use of longer time steps than in the original code.

  16. DISSECTING THE STELLAR-MASS-SFR CORRELATION IN z = 1 STAR-FORMING DISK GALAXIES

    SciTech Connect

    Salmi, F.; Daddi, E.; Elbaz, D.; Sargent, M. T.; Bethermin, M.; Renzini, A.; Le Borgne, D. E-mail: edaddi@cea.fr

    2012-07-20

    Using a mass-limited sample of 24 {mu}m detected, star-forming galaxies at 0.5 < z < 1.3, we study the mass-star formation rate (SFR) correlation and its tightness. The correlation is well defined ({sigma} = 0.28 dex) for disk galaxies (n{sub Sersic} < 1.5), while more bulge-dominated objects often have lower specific SFRs (sSFRs). For disk galaxies, a much tighter correlation ({sigma} = 0.19 dex) is obtained if the rest-frame H-band luminosity is used instead of stellar mass derived from multi-color photometry. The sSFR correlates strongly with rest-frame optical colors (hence luminosity-weighted stellar age) and also with clumpiness (which likely reflects the molecular gas fraction). This implies that most of the observed scatter is real, despite its low level, and not dominated by random measurement errors. After correcting for these differential effects a remarkably small dispersion remains ({sigma} = 0.14 dex), suggesting that measurement errors in mass or SFR are {approx}< 0.10 dex, excluding systematic uncertainties. Measurement errors in stellar masses, the thickening of the correlation due to real sSFR variations, and varying completeness with stellar mass, can spuriously bias the derived slope to lower values due to the finite range over which observables (mass and SFR) are available. When accounting for these effects, the intrinsic slope for the main sequence for disk galaxies gets closer to unity.

  17. Effects of stellar rotation on star formation rates and comparison to core-collapse supernova rates

    SciTech Connect

    Horiuchi, Shunsaku; Beacom, John F.; Bothwell, Matt S.; Thompson, Todd A.

    2013-06-01

    We investigate star formation rate (SFR) calibrations in light of recent developments in the modeling of stellar rotation. Using new published non-rotating and rotating stellar tracks, we study the integrated properties of synthetic stellar populations and find that the UV to SFR calibration for the rotating stellar population is 30% smaller than for the non-rotating stellar population, and 40% smaller for the Hα to SFR calibration. These reductions translate to smaller SFR estimates made from observed UV and Hα luminosities. Using the UV and Hα fluxes of a sample of ∼300 local galaxies, we derive a total (i.e., sky-coverage corrected) SFR within 11 Mpc of 120-170 M {sub ☉} yr{sup –1} and 80-130 M {sub ☉} yr{sup –1} for the non-rotating and rotating estimators, respectively. Independently, the number of core-collapse supernovae discovered in the same volume requires a total SFR of 270{sub −80}{sup +110} M{sub ⊙} yr{sup −1}, suggesting a tension with the SFR estimates made with rotating calibrations. More generally, when compared with the directly estimated SFR, the local supernova discoveries strongly constrain any physical effects that might increase the energy output of massive stars, including, but not limited to, stellar rotation. The cosmic SFR and cosmic supernova rate data, on the other hand, show the opposite trend, with the cosmic SFR higher than that inferred from cosmic supernovae, constraining a significant decrease in the energy output of massive stars. Together, these lines of evidence suggest that the true SFR calibration factors cannot be too far from their canonical values.

  18. MANAGEMENT ASSESSMENT AN INTEGRATED ENVIRONMENT SAFETY & HEALTH MANAGEMENT SYSTEM (ISMS) CORE FUNCTION FOR FEEDBACK & CONTINUOUS IMPROVEMENT

    SciTech Connect

    VON WEBER, M.

    2005-07-26

    Management assessment is required of US Department of Energy contractors by 10 CFR 830.122 and DOE Order 414.1. The management assessment process is a rigorous, preplanned, forward-looking review. It is required to be performed by owners of the processes that are being assessed. Written from the perspective of the Assessment Program Director and an Assessment Specialist, this paper describes the evolution of the process used by CH2MHILL to implement its management assessment program over the past two years including: roles, responsibilities, and details about our program improvement project designed to produce a clear picture of management processes and to identify opportunities for improvement. The management assessment program is essential to successful implementation, maintenance, and improvement of the CH2MHILL Integrated Environment, Safety, and Health Management System (ISMS). The management assessment program implements, in part, ISMS Core Function No. 5. ''Feedback and Continuous Improvement''. Organizations use the management assessment process to assess ISMS implementation and effectiveness. Management assessments evaluate the total picture of how well management processes are meeting organizational objectives and the customer's requirements and expectations. The emphasis is on management issues affecting performance, systems, and processes such as: strategic planning, qualification, training, staffing, organizational interfaces, communication, cost and schedule control and mission objectives. Management assessments should identify any weaknesses in the management aspects of performance and make process improvements. All managers from first line supervisors to the president and general manager are involved in the management assessment process. More senior managers, in conducting their assessment, will use data from lower levels of management. This approach will facilitate the objective of having managers closer to the work under review focusing on more

  19. An improved method for field extraction and laboratory analysis of large, intact soil cores

    USGS Publications Warehouse

    Tindall, J.A.; Hemmen, K.; Dowd, J.F.

    1992-01-01

    Various methods have been proposed for the extraction of large, undisturbed soil cores and for subsequent analysis of fluid movement within the cores. The major problems associated with these methods are expense, cumbersome field extraction, and inadequate simulation of unsaturated flow conditions. A field and laboratory procedure is presented that is economical, convenient, and simulates unsaturated and saturated flow without interface flow problems and can be used on a variety of soil types. In the field, a stainless steel core barrel is hydraulically pressed into the soil (30-cm diam. and 38 cm high), the barrel and core are extracted from the soil, and after the barrel is removed from the core, the core is then wrapped securely with flexible sheet metal and a stainless mesh screen is attached to the bottom of the core for support. In the laboratory the soil core is set atop a porous ceramic plate over which a soil-diatomaceous earth slurry has been poured to assure good contact between plate and core. A cardboard cylinder (mold) is fastened around the core and the empty space filled with paraffin wax. Soil cores were tested under saturated and unsaturated conditions using a hanging water column for potentials ???0. Breakthrough curves indicated that no interface flow occurred along the edge of the core. This procedure proved to be reliable for field extraction of large, intact soil cores and for laboratory analysis of solute transport.

  20. Greater Biopsy Core Number Is Associated With Improved Biochemical Control in Patients Treated With Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Wallner, Kent E.

    2010-11-15

    Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores ({<=}6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and {<=}6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy.

  1. Ultrasonic approach to the synthesis of HMX@TATB core-shell microparticles with improved mechanical sensitivity.

    PubMed

    Huang, Bing; Hao, Xiaofei; Zhang, Haobin; Yang, Zhijian; Ma, Zhigang; Li, Hongzhen; Nie, Fude; Huang, Hui

    2014-07-01

    To improve the safety of sensitive explosive HMX while maintaining explosion performance, a moderately powerful but insensitive explosive TATB was used to coat HMX microparticles via a facile ultrasonic method. By using Estane as surface modifier and nano-sized TATB as the shell layer, the HMX@TATB core-shell microparticles with a monodisperse size and compact shell structure were successfully constructed. Both scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) results confirmed the formation of perfect core-shell structured composites. Based on a systematic and comparative study of the effect of experimental conditions, a possible formation mechanism of core-shell structure was proposed in detail. Moreover, the perfect core-shell HMX@TATB microparticles exhibited a unique thermal behavior and significantly improved mechanical sensitivity compared with that of the physical mixture.

  2. A Team-Based Approach to Improving Core Instructional Reading Practices within Response to Intervention

    ERIC Educational Resources Information Center

    Harlacher, Jason E.; Potter, Jon B.; Weber, Jill M.

    2015-01-01

    Core instruction is an important part of an effective response to intervention (RTI) model. To implement RTI effectively, school teams should regularly examine the effectiveness of their core instruction to determine if at least 80% of students meet the proficiency standard with core support alone. However, some educators may not have the skills…

  3. EMERGENCE OF THE KENNICUTT-SCHMIDT RELATION FROM THE SMALL-SCALE SFR-DENSITY RELATION

    SciTech Connect

    Gnedin, Nickolay Y.; Tasker, Elizabeth J.; Fujimoto, Yusuke

    2014-05-20

    We use simulations of isolated galaxies with a few parsec resolution to explore the connection between the small-scale star formation rate (SFR)-gas density relation and the induced large-scale correlation between the SFR surface density and the surface density of the molecular gas (the Kennicutt-Schmidt relation). We find that, in the simulations, a power-law small-scale ''star formation law'' directly translates into an identical power-law Kennicutt-Schmidt relation. If this conclusion holds in the reality as well, it implies that the observed approximately linear Kennicutt-Schmidt relation must reflect the approximately linear small-scale ''star formation law''.

  4. Deception of ambient and body core temperature improves self paced cycling in hot, humid conditions.

    PubMed

    Castle, Paul C; Maxwell, Neil; Allchorn, Alan; Mauger, Alexis R; White, Danny K

    2012-01-01

    We used incorrect visual feedback of ambient and core temperature in the heat to test the hypothesis that deception would alleviate the decrement in cycling performance compared to a no deception trial. Seven males completed three 30 min cycling time trials in a randomised order on a Kingcycle ergometer. One time trial was in temperate, control conditions (CON: 21.8 ± 0.6°C; 43.3 ± 4.3%rh), the others in hot, humid conditions (HOT: 31.4 ± 0.3°C; 63.9 ± 4.5%rh). In one of the hot, humid conditions (31.6 ± 0.5°C; 65.4 ± 4.3%rh), participants were deceived (DEC) into thinking the ambient conditions were 26.0°C; 60.0%rh and their core temperature was 0.3°C lower than it really was. Compared to CON (16.63 ± 2.43 km) distance covered was lower in HOT (15.88 ± 2.75 km; P < 0.05), but DEC ameliorated this (16.74 ± 2.87 km; P < 0.05). Mean power output was greater in DEC (184.4 ± 60.4 W) than HOT (168.1 ± 54.1 W; P < 0.05) and no difference was observed between CON and DEC. Rectal temperature and iEMG of the vastus lateralis were not different, but RPE in the third minute was lower in DEC than HOT (P < 0.05). Deception improved performance in the heat by creating a lower RPE, evidence of a subtle mismatch between the subconscious expectation and conscious perception of the task demands.

  5. ADRIANA project: Identification of research infrastructures for the SFR, within the frame of European industrial initiative for sustainable nuclear fission

    SciTech Connect

    Latge, C.; Gastaldi, O.; Vala, L.; Gerbeth, G.; Homann, C.; Benoit, P.; Papin, J.; Girault, N.; Roelofs, F.; Bucenieks, I.; Paffumi, E.; Ciampichetti, A.

    2012-07-01

    Fast neutron reactors have a large potential as sustainable energy source. In particular, Sodium Fast Reactors (SFR) with a closed fuel cycle and potential for minor actinide burning may allow minimization of volume and heat load of high level waste and provide improved use of natural resources (as compared to only 1% energy recovery in the current once-through fuel cycle, with Thermal Reactors, such as EPR). The coordinating action ADRIANA (Advanced Reactor Initiative And Network Arrangement) has been initiated to set up a network dedicated to the construction and operation of research infrastructures in support of developments for the European Industrial Initiative for sustainable nuclear fission. The Project sets these objectives for the following reactor systems and related technologies: Sodium Fast Reactor (SFR), Lead Fast Reactor (LFR), Gas Fast Reactor (GFR, including very high temperature technologies), Instrumentation, diagnostics and experimental devices, Irradiation facilities and hot laboratories, Zero power reactors. Among the fast reactor systems, the sodium cooled reactor has the most comprehensive technological basis as result of the experience gained from worldwide operation of several experimental, prototype and commercial size reactors, since the forties (see Appendix I). This concept is currently considered as the reference, within the European strategy. Innovations are needed to further enhance safety, reduce capital cost and improve efficiency reliability and operability, making the Generation IV SFR an attractive option for electricity production. Currently, in France, a moderate (500 to 600 MWe) power demonstrator named ASTRID (Advanced Sodium Test Reactor for Industrial Demonstration) has been proposed and endorsed by EU. Presently, the reference configuration is a pool concept. General R and D needs have been identified and experimental facilities required to satisfy these needs have been listed for the following domains: material and

  6. Role for the Mammalian Swi5-Sfr1 Complex in DNA Strand Break Repair through Homologous Recombination

    PubMed Central

    Akamatsu, Yufuko; Jasin, Maria

    2010-01-01

    In fission yeast, the Swi5-Sfr1 complex plays an important role in homologous recombination (HR), a pathway crucial for the maintenance of genomic integrity. Here we identify and characterize mammalian Swi5 and Sfr1 homologues. Mouse Swi5 and Sfr1 are nuclear proteins that form a complex in vivo and in vitro. Swi5 interacts in vitro with Rad51, the DNA strand-exchange protein which functions during HR. By generating Swi5−/− and Sfr1−/− embryonic stem cell lines, we found that both proteins are mutually interdependent for their stability. Importantly, the Swi5-Sfr1 complex plays a role in HR when Rad51 function is perturbed in vivo by expression of a BRC peptide from BRCA2. Swi5−/− and Sfr1−/− cells are selectively sensitive to agents that cause DNA strand breaks, in particular ionizing radiation, camptothecin, and the Parp inhibitor olaparib. Consistent with a role in HR, sister chromatid exchange induced by Parp inhibition is attenuated in Swi5−/− and Sfr1−/− cells, and chromosome aberrations are increased. Thus, Swi5-Sfr1 is a newly identified complex required for genomic integrity in mammalian cells with a specific role in the repair of DNA strand breaks. PMID:20976249

  7. CF6 jet engine performance improvement program. Short core exhaust nozzle performance improvement concept. [specific fuel consumption reduction

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1979-01-01

    The short core exhaust nozzle was evaluated in CF6-50 engine ground tests including performance, acoustic, and endurance tests. The test results verified the performance predictions from scale model tests. The short core exhaust nozzle provides an internal cruise sfc reduction of 0.9 percent without an increase in engine noise. The nozzle hardware successfully completed 1000 flight cycles of endurance testing without any signs of distress.

  8. Multifunctional Low-Pressure Turbine for Core Noise Reduction, Improved Efficiency, and Nitrogen Oxide (NOx) Reduction

    NASA Technical Reports Server (NTRS)

    Miller, Christopher J.; Shyam, Vikram; Rigby, David L.

    2013-01-01

    This work studied the feasibility of using Helmholtz resonator cavities embedded in low-pressure-turbine (LPT) airfoils to (1) reduce core noise by damping acoustic modes; (2) use the synthetic jets produced by the liner hole acoustic oscillations to improve engine efficiency by maintaining turbulent attached flow in the LPT at low-Reynolds-number cruise conditions; and (3) reduce engine nitrogen oxide emissions by lining the internal cavities with materials capable of catalytic conversion. Flat plates with embedded Helmholtz resonators, designed to resonate at either 3000 or at 400 Hz, were simulated using computational fluid dynamics. The simulations were conducted for two inlet Mach numbers, 0.25 and 0.5, corresponding to Reynolds numbers of 90 000 and 164 000 based on the effective chordwise distance to the resonator orifice. The results of this study are (1) the region of acoustic treatment may be large enough to have a benefit; (2) the jets may not possess sufficient strength to reduce flow separation (based on prior work by researchers in the flow control area); and (3) the additional catalytic surface area is not exposed to a high velocity, so it probably does not have any benefit.

  9. Building the Missing Link between the Common Core and Improved Learning

    ERIC Educational Resources Information Center

    Rodde, Amy Coe; McHugh, Lija

    2013-01-01

    The Common Core State Standards, adopted by 45 states and the District of Columbia, raise the bar for what students need to learn at each stage of their K-12 education. The goal is to better prepare students for college and careers. The most important thing that education leaders can do to help the Common Core succeed is to support teachers in…

  10. Application of the IGSN for improved data - sample - drill core linkage

    NASA Astrophysics Data System (ADS)

    Behnken, Andree; Wallrabe-Adams, Hans-Joachim; Röhl, Ursula; Krysiak, Frank

    2016-04-01

    The large number of samples resulting from geoscientific research creates a need for a system that has the ability to allocate unique identifiers for individual samples (cores, core sections, rock samples...). In this abstract we present a solution that utilises the IGSN (1) Registry Metadata Store (2) to automatically register unique IGSN's for samples and submit corresponding metadata. An automated workflow has been set up to register IGSN's and submit metadata for cores stored for example at the IODP (3) Bremen Core Repository (BCR) in Bremen and the BGR National Core Repository for Research Drilling in Berlin, and partly transfer the core information to the GESEP (4) Virtual Core Repository (5). Detailed metadata for these cores are stored in a DIS (6), from which xml files containing all necessary information for IGSN and metadata submission are automatically generated. These files are automatically processed to extract and register the unique IGSN as well as the corresponding metadata. After this parsing process, the IGSN registration and metadata submission processes are triggered by posting the appropriate IGSN API (7) service calls. 1. International Geo Sample Number 2. https://doidb.wdc-terra.org/igsn/ 3. Integrated Ocean Drilling Program / International Ocean Discovery Program 4. German Scientific Earth Probing Consortium 5. http://www.gesep.org/infrastruktur/kernlager/portal/ 6. Drilling Information System 7. https://doidb.wdc-terra.org/igsn/static/apidoc

  11. Improvement of transformer core magnetic properties using the step-lap design

    NASA Astrophysics Data System (ADS)

    Valkovic, Z.; Rezic, A.

    1992-07-01

    Magnetic properties of the step-lap joints have been investigated experimentally on two three-phase three-leg transformer cores. Using the step-lap joint design, a reduction of the total core loss of 2 to 4.4% and of the exciting power of 31 to 37% has been obtained.

  12. The integration of single fiber reflectance (SFR) spectroscopy during endoscopic ultrasound-guided fine needle aspirations (EUS-FNA) in pancreatic masses: a feasibility study

    NASA Astrophysics Data System (ADS)

    Stegehuis, Paulien L.; Boogerd, Leonora S. F.; Inderson, Akin; Veenendaal, Roeland A.; Bonsing, Bert A.; Amelink, Arjen; Vahrmeijer, Alexander L.; Dijkstra, Jouke; Robinson, Dominic J.

    2016-03-01

    EUS-FNA can be used for pathological confirmation of a suspicious pancreatic mass. However, performance depends on an on-site cytologist and time between punction and final pathology results can be long. SFR spectroscopy is capable of extracting biologically relevant parameters (e.g. oxygenation and blood volume) in real-time from a very small tissue volume at difficult locations. In this study we determined feasibility of the integration of SFR spectroscopy during EUSFNA procedures in pancreatic masses. Patients with benign and malignant pancreatic masses who were scheduled for an EUS-FNA were included. The working guide wire inside the 19 gauge endoscopic biopsy needle was removed and the sterile single fiber (300 μm core and 700 μm outer diameter, wide-angle beam, NA 0.22) inserted through the needle. Spectroscopy measurements in the visiblenear infrared wavelength region (400-900 nm) and autofluorescence measurements (excitation at 405 nm) were taken three times, and subsequently cytology was obtained. Wavelength dependent optical properties were compared to cytology results. We took measurements in 13 patients with corresponding cytology results (including mucinous tumor, ductal adenocarcinoma, neuroendocrine tumor, and pancreatitis). In this paper we show the first analyzed results comparing normal pancreatic tissue with cancerous tissue in the same patient. We found a large difference in blood volume fraction, and blood oxygenation was higher in normal tissue. Integration of SFR spectroscopy is feasible in EUS-FNA procedures, the workflow hardly requires changes and it takes little time. The first results differentiating normal from tumor tissue are promising.

  13. In vitro hyperthermia with improved colloidal stability and enhanced SAR of magnetic core/shell nanostructures.

    PubMed

    Patil, R M; Thorat, N D; Shete, P B; Otari, S V; Tiwale, B M; Pawar, S H

    2016-02-01

    Magnetic core/shell nanostructures of Fe3O4 nanoparticles coated with oleic acid and betaine-HCl were studied for their possible use in magnetic fluid hyperthermia (MFH). Their colloidal stability and heat induction ability were studied in different media viz. phosphate buffer solution (PBS), saline solution and glucose solution with different physiological conditions and in human serum. The results showed enhanced colloidal stability in these media owing to their high zeta potential values. Heat induction studies showed that specific absorption rates (SAR) of core/shells were 82-94W/g at different pH of PBS and concentrations of NaCl and glucose. Interestingly, core/shells showed 78.45±3.90W/g SAR in human serum. The cytotoxicity of core/shells done on L929 and HeLa cell lines using 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide and trypan blue dye exclusion assays showed >89% and >80% cell viability for 24 and 48h respectively. Core/shell structures were also found to be very efficient for in vitro MFH on cancer cell line. About 95% cell death was occurred in 90min after hyperthermia treatment. The mechanism of cell death was found to be elevated ROS generation in cells after exposure to core/shells in external magnetic field. This study showed that these core/shells have a great potential to be used in in vivo MFH. PMID:26652424

  14. HUBBLE'S NEW IMPROVED OPTICS PROBE THE CORE OF A DISTANT GALAXY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This comparison image of the core of the galaxy M100 shows the dramatic improvement in Hubble Space Telescope's view of the universe. The new image was taken with the second generation Wide Field and Planetary Camera (WFPC-2) which was installed during the STS-61 Hubble Servicing Mission. The picture beautifully demonstrates that the corrective optics incorporated within the WFPC-2 compensate fully for optical aberration in Hubble's primary mirror. The new camera will allow Hubble to probe the universe with unprecedented clarity and sensitivity, and to fulfill many of the most important scientific objectives for which the telescope was originally built. [ Right ] The core of the grand design spiral galaxy M100, as imaged by Hubble Space Telescope's Wide Field Planetary Camera 2 in its high resolution channel. The WFPC-2 contains modified optics that correct for Hubble's previously blurry vision, allowing the telescope for the first time to cleanly resolve faint structure as small as 30 light-years across in a galaxy which is tens of millions of light years away. The image was taken on December 31, 1993. [Left ] For comparison, a picture taken with the WFPC-1 camera in wide field mode, on November 27, 1993, just a few days prior to the STS-61 servicing mission. The effects of optical aberration in HST's 2.4-meter primary mirror blur starlight, smear out fine detail, and limit the telescope's ability to see faint structure. Both Hubble images are 'raw;' they have not been subject to computer image reconstruction techniques commonly used in aberrated images made before the servicing mission. TARGET INFORMATION: M100 The galaxy M100 (100th object in the Messier Catalog of non-stellar objects) is one of the brightest members of the Virgo Cluster of galaxies. The galaxy is in the spring constellation Coma Berenices and can be seen through a moderate-sized amateur telescope. M100 is spiral shaped, like our Milky Way, and tilted nearly face-on as seen from earth. The

  15. Design and Performance Improvements of the Prototype Open Core Flywheel Energy Storage System

    NASA Technical Reports Server (NTRS)

    Pang, D.; Anand, D. K. (Editor); Kirk, J. A. (Editor)

    1996-01-01

    A prototype magnetically suspended composite flywheel energy storage (FES) system is operating at the University of Maryland. This system, designed for spacecraft applications, incorporates recent advances in the technologies of composite materials, magnetic suspension, and permanent magnet brushless motor/generator. The current system is referred to as an Open Core Composite Flywheel (OCCF) energy storage system. This paper will present design improvements for enhanced and robust performance. Initially, when the OCCF prototype was spun above its first critical frequency of 4,500 RPM, the rotor movement would exceed the space available in the magnetic suspension gap and touchdown on the backup mechanical bearings would occur. On some occasions it was observed that, after touchdown, the rotor was unable to re-suspend as the speed decreased. Additionally, it was observed that the rotor would exhibit unstable oscillations when the control system was initially turned on. Our analysis suggested that the following problems existed: (1) The linear operating range of the magnetic bearings was limited due to electrical and magnetic saturation; (2) The inductance of the magnetic bearings was affecting the transient response of the system; (3) The flywheel was confined to a small movement because mechanical components could not be held to a tight tolerance; and (4) The location of the touchdown bearing magnifies the motion at the pole faces of the magnetic bearings when the linear range is crucial. In order to correct these problems an improved design of the flywheel energy storage system was undertaken. The magnetic bearings were re-designed to achieve a large linear operating range and to withstand load disturbances of at least 1 g. The external position transducers were replaced by a unique design which were resistant to magnetic field noise and allowed cancellation of the radial growth of the flywheel at high speeds. A central rod was utilized to ensure the concentricity

  16. [Improvement of sensitivity in the second generation HCV core antigen assay by a novel concentration method using polyethylene glycol (PEG)].

    PubMed

    Higashimoto, Makiko; Takahashi, Masahiko; Jokyu, Ritsuko; Syundou, Hiromi; Saito, Hidetsugu

    2007-11-01

    A HCV core antigen (Ag) detection assay system, Lumipulse Ortho HCV Ag has been developed and is commercially available in Japan with a lower detection level limit of 50 fmol/l, which is equivalent to 20 KIU/ml in PCR quantitative assay. HCV core Ag assay has an advantage of broader dynamic range compared with PCR assay, however the sensitivity is lower than PCR. We developed a novel HCV core Ag concentration method using polyethylene glycol (PEG), which can improve the sensitivity five times better than the original assay. The reproducibility was examined by consecutive five-time measurement of HCV patients serum, in which the results of HCV core Ag original and concentrated method were 56.8 +/- 8.1 fmol/l (mean +/- SD), CV 14.2% and 322.9 +/- 45.5 fmol/l CV 14.0%, respectively. The assay results of HCV negative samples in original HCV core Ag were all 0.1 fmol/l and the results were same even in the concentration method. The results of concentration method were 5.7 times higher than original assay, which was almost equal to theoretical rate as expected. The assay results of serially diluted samples were also as same as expected data in both original and concentration assay. We confirmed that the sensitivity of HCV core Ag concentration method had almost as same sensitivity as PCR high range assay in the competitive assay study using the serially monitored samples of five HCV patients during interferon therapy. A novel concentration method using PEG in HCV core Ag assay system seems to be useful for assessing and monitoring interferon treatment for HCV.

  17. Evaluation of post-surface conditioning to improve interfacial adhesion in post-core restorations

    PubMed Central

    Sumitha, Mylswamy; Kothandaraman, Rajkumar; Sekar, Mahalaxmi

    2011-01-01

    Aim: To examine the influence of different post-surface treatments on the interfacial strength between epoxy resin-based fiber posts and methacrylate-based resin composites that are employed as core build-up materials. Materials and Methods: Forty clear posts were divided into four groups of 10 each. The different surface treatments used were etching with alkaline potassium permanganate, 10% hydrogen peroxide, 37% phosphoric acid, and silanization alone. After etching and thorough rinsing, a single layer of silane was applied to the post surface. Then the post was placed in a rectangular plastic matrix and core bulid-up was done using Multi Core, a dual cured composite resin. A slab of uniform thickness, with the post in the center and the core build-up composite on either side was created. The specimens were cut so as to obtain microtensile sticks that were loaded in tension at a cross-head speed of 1 mm/min until failure. The statistical analysis was performed using two-way ANOVA and the paired T test for post-hoc comparisons. Results: The results achieved with potassium permanganate had a significant influence on microtensile interfacial bond strength values with the tested material. Conclusion: Surface chemical treatments of the resin phase of fiber posts enhance the silanization efficiency of the quartz fiber phase, so that the adhesion in the post/core unit may be considered as a net sum of chemical and micromechanical retention. PMID:21691501

  18. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis.

    PubMed

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-19

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants. PMID:27160795

  19. Improvements in Sand Mold/Core Technology: Effects on Casting Finish

    SciTech Connect

    Prof. John J. Lannutti; Prof. Carroll E. Mobley

    2005-08-30

    In this study, the development and impact of density gradients on metal castings were investigated using sand molds/cores from both industry and from in-house production. In spite of the size of the castings market, almost no quantitative information about density variation within the molds/cores themselves is available. In particular, a predictive understanding of how structure and binder content/chemistry/mixing contribute to the final surface finish of these products does not exist. In this program we attempted to bridge this gap by working directly with domestic companies in examining the issues of surface finish and thermal reclamation costs resulting from the use of sand molds/cores. We show that these can be substantially reduced by the development of an in-depth understanding of density variations that correlate to surface finish. Our experimental tools and our experience with them made us uniquely qualified to achieve technical progress.

  20. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    NASA Technical Reports Server (NTRS)

    Clark, John S.; Walton, James T.; Mcguire, Melissa L.

    1992-01-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines.

  1. Development of electromagnetic acoustic transducer (EMAT) phased arrays for SFR inspection

    SciTech Connect

    Le Bourdais, Florian; Marchand, Benoît

    2014-02-18

    A long-standing problem for Sodium cooled Fast Reactor (SFR) instrumentation is the development of efficient under-sodium visualization systems adapted to the hot and opaque sodium environment. Electromagnetic Acoustic Transducers (EMAT) are potential candidates for a new generation of Ultrasonic Testing (UT) probes well-suited for SFR inspection that can overcome drawbacks of classical piezoelectric probes in sodium environment. Based on the use of new CIVA simulation tools, we have designed and optimized an advanced EMAT probe for under-sodium visualization. This has led to the development of a fully functional L-wave EMAT sensing system composed of 8 elements and a casing withstanding 200° C sodium inspection. Laboratory experiments demonstrated the probe's ability to sweep an ultrasonic beam to an angle of 15 degrees. Testing in a specialized sodium facility has shown that it was possible to obtain pulse-echo signals from a target under several different angles from a fixed position.

  2. Development of electromagnetic acoustic transducer (EMAT) phased arrays for SFR inspection

    NASA Astrophysics Data System (ADS)

    Le Bourdais, Florian; Marchand, Benoît

    2014-02-01

    A long-standing problem for Sodium cooled Fast Reactor (SFR) instrumentation is the development of efficient under-sodium visualization systems adapted to the hot and opaque sodium environment. Electromagnetic Acoustic Transducers (EMAT) are potential candidates for a new generation of Ultrasonic Testing (UT) probes well-suited for SFR inspection that can overcome drawbacks of classical piezoelectric probes in sodium environment. Based on the use of new CIVA simulation tools, we have designed and optimized an advanced EMAT probe for under-sodium visualization. This has led to the development of a fully functional L-wave EMAT sensing system composed of 8 elements and a casing withstanding 200° C sodium inspection. Laboratory experiments demonstrated the probe's ability to sweep an ultrasonic beam to an angle of 15 degrees. Testing in a specialized sodium facility has shown that it was possible to obtain pulse-echo signals from a target under several different angles from a fixed position.

  3. LWR codes capability to address SFR BDBA scenarios: Modeling of the ABCOVE tests

    SciTech Connect

    Herranz, L. E.; Garcia, M.; Morandi, S.

    2012-07-01

    The sound background built-up in LWR source term analysis in case of a severe accident, make it worth to check the capability of LWR safety analysis codes to model accident SFR scenarios, at least in some areas. This paper gives a snapshot of such predictability in the area of aerosol behavior in containment. To do so, the AB-5 test of the ABCOVE program has been modeled with 3 LWR codes: ASTEC, ECART and MELCOR. Through the search of a best estimate scenario and its comparison to data, it is concluded that even in the specific case of in-containment aerosol behavior, some enhancements would be needed in the LWR codes and/or their application, particularly with respect to consideration of particle shape. Nonetheless, much of the modeling presently embodied in LWR codes might be applicable to SFR scenarios. These conclusions should be seen as preliminary as long as comparisons are not extended to more experimental scenarios. (authors)

  4. OSCAR-Na: A New Code for Simulating Corrosion Product Contamination in SFR

    NASA Astrophysics Data System (ADS)

    Génin, J.-B.; Brissonneau, L.; Gilardi, T.

    2016-07-01

    A code named OSCAR-Na has been developed to calculate the mass transfer of corrosion products in the primary circuit of sodium fast reactors (SFR). It is based on a solution/precipitation model, including diffusion in the steel (enhanced under irradiation), diffusion through the sodium boundary layer, equilibrium concentration of each element, and velocity of the interface (bulk corrosion or deposition). The code uses a numerical method for solving the diffusion equation in the steel and the complete mass balance in sodium for all elements. Corrosion and deposition rates are mainly determined by the iron equilibrium concentration in sodium and its oxygen-enhanced dissolution rate. All parameters of the model have been assessed from a literature review, but iron solubility had to be adjusted. A simplified primary system description of PHENIX French SFR was able to assess the correct amounts and profiles of contamination on heat exchanger surfaces for the main radionuclides.

  5. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome.

    PubMed

    Chevidikunnan, Mohamed Faisal; Al Saif, Amer; Gaowgzeh, Riziq Allah; Mamdouh, Khaled A

    2016-05-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and control (N=10) groups. Both groups were given 4 weeks of conventional physical therapy program and an additional core muscle strengthening for the study group. The tools used to assess the outcome were Visual Analogue Scale and Star Excursion Balance Test. [Results] The results of the study show that participants in the study group revealed a significantly greater improvement in the intensity of pain and dynamic balance as compared to the control group. [Conclusion] Adding a core muscle-strengthening program to the conventional physical therapy management improves pain and dynamic balance in female patients with patellofemoral pain syndrome. PMID:27313363

  6. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome

    PubMed Central

    Chevidikunnan, Mohamed Faisal; Al Saif, Amer; Gaowgzeh, Riziq Allah; Mamdouh, Khaled A

    2016-01-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and control (N=10) groups. Both groups were given 4 weeks of conventional physical therapy program and an additional core muscle strengthening for the study group. The tools used to assess the outcome were Visual Analogue Scale and Star Excursion Balance Test. [Results] The results of the study show that participants in the study group revealed a significantly greater improvement in the intensity of pain and dynamic balance as compared to the control group. [Conclusion] Adding a core muscle-strengthening program to the conventional physical therapy management improves pain and dynamic balance in female patients with patellofemoral pain syndrome. PMID:27313363

  7. Improved oxygen reduction activity on the Ih Cu@Pt core-shell nanoparticles

    NASA Astrophysics Data System (ADS)

    Yang, Zongxian; Geng, Zhixia; Zhang, Yanxing; Wang, Jinlong; Ma, Shuhong

    2011-09-01

    The minimum energy path (MEP) for the dissociation of O 2 on the Ih Cu@Pt12 core-shell nanoparticle. Ih Cu@Pt12 is the most stable among the symmetric Cu@Pt12 core-shell isomers. O 2 prefers to be adsorbed on the Ih Cu@Pt12 with the t-b-t configuration. The Ih Cu@Pt12 has enhanced activity for O 2 dissociation and O diffusion. Ih Cu@Pt12 nanoparticle is a good candidate for being the ORR catalyst.

  8. Core ADHD Symptom Improvement with Atomoxetine versus Methylphenidate: A Direct Comparison Meta-Analysis

    ERIC Educational Resources Information Center

    Hazell, Philip L.; Kohn, Michael R.; Dickson, Ruth; Walton, Richard J.; Granger, Renee E.; van Wyk, Gregory W.

    2011-01-01

    Objective: Previous studies comparing atomoxetine and methylphenidate to treat ADHD symptoms have been equivocal. This noninferiority meta-analysis compared core ADHD symptom response between atomoxetine and methylphenidate in children and adolescents. Method: Selection criteria included randomized, controlled design; duration 6 weeks; and…

  9. Assessing the Common Core Standards: Opportunities for Improving Measures of Instruction

    ERIC Educational Resources Information Center

    Porter, Andrew; McMaken, Jennifer; Hwang, Jun; Yang, Rui

    2011-01-01

    This article responds to comments on the authors' "Educational Researcher" article "Common Core Standards: The New U.S. Intended Curriculum" (April 2011). The authors note points of agreement and difference with the commentators. They observe that Cobb and Jackson, in their response, and Beach, in his, appear to accept the authors' methods and…

  10. Improved diamond coring bits developed for dry and chip-flush drilling

    NASA Technical Reports Server (NTRS)

    Decker, W. E.; Hampe, W. R.; Hampton, W. H.; Simon, A. B.

    1971-01-01

    Two rotary diamond bit designs, one operating with a chip-flushing fluid, the second including auger section to remove drilled chips, enhance usefulness of tool for exploratory and industrial core-drilling of hard, abrasive mineral deposits and structural masonry.

  11. Improved Fabrication of Ceramic Matrix Composite/Foam Core Integrated Structures

    NASA Technical Reports Server (NTRS)

    Hurwitz, Frances I.

    2009-01-01

    The use of hybridized carbon/silicon carbide (C/SiC) fabric to reinforce ceramic matrix composite face sheets and the integration of such face sheets with a foam core creates a sandwich structure capable of withstanding high-heatflux environments (150 W/cm2) in which the core provides a temperature drop of 1,000 C between the surface and the back face without cracking or delamination of the structure. The composite face sheet exhibits a bilinear response, which results from the SiC matrix not being cracked on fabrication. In addition, the structure exhibits damage tolerance under impact with projectiles, showing no penetration to the back face sheet. These attributes make the composite ideal for leading edge structures and control surfaces in aerospace vehicles, as well as for acreage thermal protection systems and in high-temperature, lightweight stiffened structures. By tailoring the coefficient of thermal expansion (CTE) of a carbon fiber containing ceramic matrix composite (CMC) face sheet to match that of a ceramic foam core, the face sheet and the core can be integrally fabricated without any delamination. Carbon and SiC are woven together in the reinforcing fabric. Integral densification of the CMC and the foam core is accomplished with chemical vapor deposition, eliminating the need for bond-line adhesive. This means there is no need to separately fabricate the core and the face sheet, or to bond the two elements together, risking edge delamination during use. Fibers of two or more types are woven together on a loom. The carbon and ceramic fibers are pulled into the same pick location during the weaving process. Tow spacing may be varied to accommodate the increased volume of the combined fiber tows while maintaining a target fiber volume fraction in the composite. Foam pore size, strut thickness, and ratio of face sheet to core thickness can be used to tailor thermal and mechanical properties. The anticipated CTE for the hybridized composite is managed by

  12. Cloning and analysis of the sfrB (sex factor repression) gene of Escherichia coli K-12.

    PubMed Central

    Rehemtulla, A; Kadam, S K; Sanderson, K E

    1986-01-01

    The sfrB gene of Escherichia coli K-12 and the rfaH gene of Salmonella typhimurium LT2 are homologous, controlling expression of the tra operon of F and the rfa genes for lipopolysaccharide synthesis. We have determined a restriction map of the 19-kilobase ColE1 plasmid pLC14-28 which carries the sfrB gene of E. coli. After partial Sau3A digestion of pLC14-28, we cloned a 2.5-kilobase DNA fragment into the BamHI site of pBR322 to form pKZ17. pKZ17 complemented mutants of the sfrB gene of E. coli and the rfaH gene of S. typhimurium for defects of both the F tra operon and the rfa genes. pKZ17 in minicells determines an 18-kilodalton protein not determined by pBR322. A Tn5 insertion into the sfrB gene causes loss of complementing activity and loss of the 18-kilodalton protein in minicells, indicating that this protein is the sfrB gene product. These data indicate that the sfrB gene product is a regulatory element, since the single gene product elicits the expression of genes for many products for F expression and lipopolysaccharide synthesis. Images PMID:3009418

  13. Improved fluorescence properties of core-sheath electrospun nanofibers sensitized by silver nanoparticles

    NASA Astrophysics Data System (ADS)

    Wen, Shipeng; Zhang, Rong; Hu, Shui; Zhang, Liqun; Liu, Li

    2015-09-01

    Silver nanoparticles (Ag-NPs) were used to enhance the fluorescence properties of nanofibers containing the Tb(acac)3phen (Tb = terbium, acac = acetylacetone, phen = 1,10-phenanthroline) complex. Tb(acac)3phen/PLLA//Ag-NPs/PVP (PLLA = polylacticacid, PVP = polyvinylpyrrolidone) core-sheath fluorescence nanofibers were prepared by coaxial electrospinning. SEM images demonstrated that the fibers had an average diameter of 550 nm. TEM images illustrated that the Ag-NPs and Tb(acac)3phen were uniformly dispersed in the outer and inner fibrous layers in the form of nanoparticles and molecular clusters, respectively. The fluorescence intensity of the Tb(acac)3phen/PLLA//Ag-NPs/PVP core-sheath nanofibers with a molar ratio Ag/Tb of 1 increased by 69%, the quantum efficiency increased by 53%, and the fluorescence lifetime increased by 4% over those of the fibers without Ag-NPs because of the localized surface plasmon resonance (LSPR) effect of Ag-NPs. The prepared fibers with a core-sheath structure have great potential in a wide range of fluorescence applications.

  14. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    SciTech Connect

    Clark, J.S.; Walton, J.T.; Mcguire, M.L. Cincinnati, University, OH )

    1992-07-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines. 11 refs.

  15. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis

    NASA Astrophysics Data System (ADS)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-01

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic

  16. Casting evaluation of U-Zr alloy system fuel slug for SFR prepared by injection casting method

    SciTech Connect

    Song, Hoon; Kim, Jong-Hwan; Kim, Ki-Hwan; Lee, Chan-Bock

    2013-07-01

    Metal fuel slugs of U-Pu-Zr alloys for Sodium-cooled Fast Reactor (SFR) have conventionally been fabricated by a vacuum injection casting method. Recently, management of minor actinides (MA) became an important issue because direct disposal of the long-lived MA can be a long-term burden for a tentative repository up to several hundreds of thousand years. In order to recycle transuranic elements (TRU) retained in spent nuclear fuel, remote fabrication capability in a shielded hot cell should be prepared. Moreover, generation of long-lived radioactive wastes and loss of volatile species should be minimized during the recycled fuel fabrication step. In order to prevent the evaporation of volatile elements such as Am, alternative fabrication methods of metal fuel slugs have been studied applying gravity casting, and improved injection casting in KAERI, including melting under inert atmosphere. And then, metal fuel slugs were examined with casting soundness, density, chemical analysis, particle size distribution and microstructural characteristics. Based on these results there is a high level of confidence that Am losses will also be effectively controlled by application of a modest amount of overpressure. A surrogate fuel slug was generally soundly cast by improved injection casting method, melted fuel material under inert atmosphere.

  17. Improved models of stellar core collapse and still no explosions: what is missing?

    PubMed

    Buras, R; Rampp, M; Janka, H-Th; Kifonidis, K

    2003-06-20

    Two-dimensional hydrodynamic simulations of stellar core collapse are presented which for the first time were performed by solving the Boltzmann equation for the neutrino transport including a state-of-the-art description of neutrino interactions. Stellar rotation is also taken into account. Although convection develops below the neutrinosphere and in the neutrino-heated region behind the supernova shock, the models do not explode. This suggests missing physics, possibly with respect to the nuclear equation of state and weak interactions in the subnuclear regime. However, it might also indicate a fundamental problem with the neutrino-driven explosion mechanism.

  18. Assessment of and Improvements to Acoustic Velocimetry in Flows in Core-like Geometries

    NASA Astrophysics Data System (ADS)

    Mautino, A. R.; Adams, M. M.; Stone, D.; Triana, S. A.; Lathrop, D. P.; Lekic, V.

    2015-12-01

    Rapidly rotating fluid flows are found in a wide variety of geophysical and astrophysical contexts, including the Earth's outer core. The dynamics of such flows can be studied experimentally at conditions inaccessible to computational modeling. However, accurately measuring the mean and time-varying flows noninvasively presents a technical challenge, particularly in opaque liquids. In this study, we tackle the problem of mapping zonal flow profiles in spherical Couette flows, shear flows in a core-like geometry. These rotating flows induce shifts and splittings in the spectrum of the acoustically resonant fluid-filled cavity. The azimuthal component of flow can be estimated from the spectra of the acoustic modes, using inversion procedures adapted from Helioseismology. Here, we present a technique for reconstructing the mean velocity field using modal analysis by way of the Finite Element Method, which is used to compute the forward model accurately, taking into account structural geometries associated with the experimental setups, such as shafts and axles. Accurate forward modeling is crucial for reliable mode identification, and we demonstrate that it allows us to identify many more modes than is possible when using the spherically symmetric approximation. We model flow geometry as a superposition of low order basis flow patterns, each of which affects mode frequency splittings and shifts through advection and Coriolis forces.

  19. Can Technology Improve Large Class Learning? The Case of an Upper-Division Business Core Class

    ERIC Educational Resources Information Center

    Stanley, Denise

    2013-01-01

    Larger classes are often associated with lower student achievement. The author tested the hypothesis that the introduction of personal response systems significantly improves scores in a 250-seat classroom, through the channels of improved attendance and engagement. She focused on how continuous participation with the technology could change…

  20. Using a Rice Mini-Core Collection to Map QTLs for Improvement of Grain Yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yield is the most important and complex trait for genetic improvement in crops, and marker-assisted selection enhances the improvement efficiency. We phenotyped 203 O. sativa accessions for 14 agronomic traits and identified five highly and significantly correlated with grain yield per plant. Genoty...

  1. Improving Middle School Parental Engagement in Transition to Common Core State Standards: An Action Research Study

    ERIC Educational Resources Information Center

    Harla, Donna K.

    2014-01-01

    Parental involvement in schools is an important potential contributor to improving American education and making the U.S. more globally competitive. This qualitative and quantitative mixed-methodology action research study probed the viability of engaging parents around issues of educational improvement by inviting them to participate in training…

  2. Performance evaluation of two-stage fuel cycle from SFR to PWR

    SciTech Connect

    Fei, T.; Hoffman, E.A.; Kim, T.K.; Taiwo, T.A.

    2013-07-01

    One potential fuel cycle option being considered is a two-stage fuel cycle system involving the continuous recycle of transuranics in a fast reactor and the use of bred plutonium in a thermal reactor. The first stage is a Sodium-cooled Fast Reactor (SFR) fuel cycle with metallic U-TRU-Zr fuel. The SFRs need to have a breeding ratio greater than 1.0 in order to produce fissile material for use in the second stage. The second stage is a PWR fuel cycle with uranium and plutonium mixed oxide fuel based on the design and performance of the current state-of-the-art commercial PWRs with an average discharge burnup of 50 MWd/kgHM. This paper evaluates the possibility of this fuel cycle option and discusses its fuel cycle performance characteristics. The study focuses on an equilibrium stage of the fuel cycle. Results indicate that, in order to avoid a positive coolant void reactivity feedback in the stage-2 PWR, the reactor requires high quality of plutonium from the first stage and minor actinides in the discharge fuel of the PWR needs to be separated and sent back to the stage-1 SFR. The electricity-sharing ratio between the 2 stages is 87.0% (SFR) to 13.0% (PWR) for a TRU inventory ratio (the mass of TRU in the discharge fuel divided by the mass of TRU in the fresh fuel) of 1.06. A sensitivity study indicated that by increasing the TRU inventory ratio to 1.13, The electricity generation fraction of stage-2 PWR is increased to 28.9%. The two-stage fuel cycle system considered in this study was found to provide a high uranium utilization (>80%). (authors)

  3. Towards a core ontology for integrating ecological and environmental ontologies to enable improved data interoperability

    NASA Astrophysics Data System (ADS)

    Bowers, S.; Madin, J.; Jones, M.; Schildhauer, M.; Ludaescher, B.

    2007-12-01

    Research in the ecological and environmental sciences increasingly relies on the integration of traditionally small, focused studies to form larger datasets for synthetic analyses. However, a broad range of data types, structures, and semantic subtleties occur in ecological data, making data discovery and integration a difficult and time-consuming task. Our work focuses on capturing the subtleties of scientific data through semantic annotations, which involve linking ecological data to concepts and relationships in domain-specific ontologies, thereby enabling more advanced forms of data discovery and integration. A variety of ontologies related to ecological data are actively being developed, ranging from low-level and highly focused vocabularies to high-level models and classifications. However, as the number of ontologies and their included terms increase, organizing these into a coherent framework useful for data annotation becomes increasingly complex (we note that similar issues have been recognized within the molecular biology and bioinformatics communities). We describe a core ontology model for semantic annotation that provides a structured approach for integrating the growing number of ecology-relevant ontologies. The ontology defines the notion of "scientific observation" as a unifying concept for capturing the basic semantics of ecological data. Observations are distinguished at the level of the entity (e.g., location, time, thing, concept), and characteristics of an entity (e.g., height, name, color) are measured (named or classified) as data. The ontology permits observations to be related via context (such as spatial or temporal containment), further supporting the discovery and automated comparison and alignment (e.g., merging) of heterogeneous data. The core ontology also defines a set of extension points that can be used to either directly build new domain ontologies (as extension ontologies), or to provide a common basis to which existing

  4. Improved Methods for Estimating Microbial Activity and Moisture Characteristic Curves in Intact Unsaturated Soil Cores

    NASA Astrophysics Data System (ADS)

    Thompson, D. N.; Baker, K. E.

    2001-12-01

    Estimation of microbial activity in soils is a complex and often difficult process. In this work, we describe several new and innovative methods we have developed to measure microbial respiration in intact cores of unsaturated soils. The ultimate goal of this work is to predict the effect of microbial activity on contaminant mobility via CO2 generation in variably saturated vadose zone soils. This goal requires estimation of the effect of available water (i.e. in pores accessible to the microbes) on the microbial activity, and thus a homogeneous distribution of substrate throughout the soil water. Prior studies have added substrate solution drop wise to the soil, and then distributed the substrate throughout the soil by mixing. While this method distributes the substrate well, it alters the in situ pore volume distribution and has been shown to result in an anomalously high degree of microbial activity shortly after mixing. Traditional methods for uniformly distributing substrate in intact unsaturated soils require days to weeks to reach equilibrium. Since the substrate would be completely consumed in this time frame, an innovative approach is being used in this study to drain intact soil cores to the desired moisture contents in a matter of hours. This approach involves the use of the Unsaturated Flow Apparatus (UFAT). In the method, the samples are vacuum saturated under refrigeration to uniformly distribute a 14C-labeled substrate throughout the soil water, drained to various pressures in the UFA, and transferred to a sealed container and incubated. The labeled 14CO2 is then trapped and counted after incubation to determine microbial activity. Since the soil used in this study contains a high percentage of swelling clays, the cores tend to compact in the UFA, altering the macropore volume distribution. To address this alteration, we developed a correction function to correct the UFA-measured pore volume distribution at each rotational speed. Finally, the high

  5. Creating a high-reliability health care system: improving performance on core processes of care at Johns Hopkins Medicine.

    PubMed

    Pronovost, Peter J; Armstrong, C Michael; Demski, Renee; Callender, Tiffany; Winner, Laura; Miller, Marlene R; Austin, J Matthew; Berenholtz, Sean M; Yang, Ting; Peterson, Ronald R; Reitz, Judy A; Bennett, Richard G; Broccolino, Victor A; Davis, Richard O; Gragnolati, Brian A; Green, Gene E; Rothman, Paul B

    2015-02-01

    In this article, the authors describe an initiative that established an infrastructure to manage quality and safety efforts throughout a complex health care system and that improved performance on core measures for acute myocardial infarction, heart failure, pneumonia, surgical care, and children's asthma. The Johns Hopkins Medicine Board of Trustees created a governance structure to establish health care system-wide oversight and hospital accountability for quality and safety efforts throughout Johns Hopkins Medicine. The Armstrong Institute for Patient Safety and Quality was formed; institute leaders used a conceptual model nested in a fractal infrastructure to implement this initiative to improve performance at two academic medical centers and three community hospitals, starting in March 2012. The initiative aimed to achieve ≥ 96% compliance on seven inpatient process-of-care core measures and meet the requirements for the Delmarva Foundation and Joint Commission awards. The primary outcome measure was the percentage of patients at each hospital who received the recommended process of care. The authors compared health system and hospital performance before (2011) and after (2012, 2013) the initiative. The health system achieved ≥ 96% compliance on six of the seven targeted measures by 2013. Of the five hospitals, four received the Delmarva Foundation award and two received The Joint Commission award in 2013. The authors argue that, to improve quality and safety, health care systems should establish a system-wide governance structure and accountability process. They also should define and communicate goals and measures and build an infrastructure to support peer learning.

  6. Improving measurement methods in rehabilitation: core concepts and recommendations for scale development.

    PubMed

    Velozo, Craig A; Seel, Ronald T; Magasi, Susan; Heinemann, Allen W; Romero, Sergio

    2012-08-01

    Validated measurement scales are essential to evaluating clinical outcomes and conducting meaningful and reliable research. The purpose of this article is to present the clinician and researcher with a contemporary 8-stage framework for measurement scale development based on a mixed-methods qualitative and quantitative approach. Core concepts related to item response theory are presented. Qualitative methods are described to conceptualize scale constructs; obtain patient, family, and other stakeholder perspectives; and develop item pools. Item response theory statistical methodologies are presented, including approaches for testing the assumptions of unidimensionality, local independence, monotonicity, and indices of model fit. Lastly, challenges faced by scale developers in implementing these methodologies are discussed. While rehabilitation research has recently started to apply mixed-methods qualitative and quantitative methodologies to scale development, these approaches show considerable promise in advancing rehabilitation measurement. PMID:22840881

  7. Core/shell-structured nickel/nitrogen-doped onion-like carbon nanocapsules with improved electromagnetic wave absorption properties

    NASA Astrophysics Data System (ADS)

    Wu, Niandu; Liu, Xianguo; Or, Siu Wing

    2016-05-01

    Core/shell-structured nickel/nitrogen-doped onion-like carbon (Ni/(C, N)) nanocapsules are synthesized by a modified arc-discharge method using N2 gas as the source of N atoms. Core/shell-structured Ni/C nanocapsules are also prepared for comparison. The Ni/(C, N) nanocapsules with diameters of 10-80 nm exhibit a clear core/shell structure. The doping of N atoms introduces more lattice defects into the (C, N) shells and creates more disorderly C in the (C, N) shells. This leads to a slight shift in the dielectric resonance peak to the lower frequency side and an increase in the dielectric loss tangent for the Ni/(C, N) nanocapsules in comparison with the Ni/C nanocapsules. The magnetic permeability of both types of nanocapsules remains almost unaltered since the N atoms exist only in the (C, N) shells. The reflection loss (RL) of the Ni/(C, N) nanocapsules not only reaches a high value of -35 dB at 13.6 GHz, but also is generally improved in the low-frequency S and C microwave bands covering 2-8 GHz as a result of the N-doping-induced additional dipolar polarization and dielectric loss from the (C, N) shells.

  8. Total Automation for the Core Laboratory: Improving the Turnaround Time Helps to Reduce the Volume of Ordered STAT Tests.

    PubMed

    Ialongo, Cristiano; Porzio, Ottavia; Giambini, Ilio; Bernardini, Sergio

    2016-06-01

    The transition to total automation represents the greatest leap for a clinical laboratory, characterized by a totally new philosophy of process management. We have investigated the impact of total automation on core laboratory efficiency and its effects on the clinical services related to STAT tests. For this purpose, a 47-month retrospective study based on the analysis of 44,212 records of STAT cardiac troponin I (CTNI) tests was performed. The core laboratory reached a new efficiency level 3 months after the implementation of total automation. Median turnaround time (TAT) was reduced by 14.9±1.5 min for the emergency department (p < 0.01), reaching 41.6±1.2 min. In non-emergency departments, median TAT was reduced by 19.8±2.2 min (p < 0.01), reaching 52±1.3 min. There was no change in the volume of ordered STAT CTNI tests by the emergency department (p = 0.811), whereas for non-emergency departments there was a reduction of 115.7±50 monthly requests on average (p = 0.026). The volume of ordered tests decreased only in time frames of the regular shift following the morning round. Thus, total automation significantly improves the core laboratory efficiency in terms of TAT. As a consequence, the volume of STAT tests ordered by hospital departments (except for the emergency department) decreased due to reduced duplicated requests.

  9. Lipid-Core Nanocapsules Improved Antiedematogenic Activity of Tacrolimus in Adjuvant-Induced Arthritis Model.

    PubMed

    Friedrich, Rossana B; Coradini, Karine; Fonseca, Francisco N; Guterres, Silvia S; Beck, Ruy C R; Pohlmann, Adriana R

    2016-02-01

    Despite significant technological advances, rheumatoid arthritis remains an incurable disease with great impact on the life quality of patients. We studied the encapsulation of tacrolimus in lipidcore nanocapsules (TAC-LNC) as a strategy to enhance its systemic anti-arthritic properties. TAC-LNC presented unimodal distribution of particles with z-average diameter of 212 +/- 11, drug content close to the theoretical value (0.80 mg mL(-1)), and 99.43% of encapsulation efficiency. An in vitro sustained release was determined for TAC-LNC with anomalous transport mechanism (n = 0.61). In vivo studies using an arthritis model induced by Complete Freund's Adjuvant demonstrated that the animals treated with TAC-LNC presented a significantly greater inhibition of paw oedema after intraperitoneal administration. Furthermore, the encapsulation of TAC in lipid-core nanocapsules was potentially able to prevent hyperglycemia in the animals. In conclusion, TAC-LNC was prepared with 100% yield of nanoscopic particles having satisfactory characteristics for systemic use. This formulation represents a promising strategy to the treatment of rheumatoid arthritis in the near future. PMID:27433576

  10. Superparamagnetic iron oxide/chitosan core/shells for hyperthermia application: Improved colloidal stability and biocompatibility

    NASA Astrophysics Data System (ADS)

    Patil, R. M.; Shete, P. B.; Thorat, N. D.; Otari, S. V.; Barick, K. C.; Prasad, A.; Ningthoujam, R. S.; Tiwale, B. M.; Pawar, S. H.

    2014-04-01

    Superparamagnetic magnetite nanoparticles are of great interest due to their potential biomedical applications. In the present investigation, Fe3O4 magnetic nanoparticles were prepared by alkaline precipitation using ferrous chloride as the sole source. An amphiphilic polyelectrolyte with the property of biocompatibility and functional carboxyl groups was used as a stabilizer to prepare a well-dispersed suspension of superparamagnetic Fe3O4 nanoparticles. The final material composed of Fe3O4 core and chitosan (CH) shell was produced. The amino groups of CH coated on Fe3O4 nanoparticles were further cross linked using glutaraldehyde (GLD) for stable coating. FTIR spectra, XPS and TGA confirmed the coating of CH/GLD on the surface of Fe3O4 nanoparticles. XRD patterns indicate the pure phase Fe3O4 with a spinel structure. The nanoparticles were superparamagnetic at room temperature with saturation magnetization values for bare and coated nanoparticles which were 51.68 emu/g and 48.60 emu/g, respectively. Zeta potential values showed higher colloidal stability of coated nanoparticles than the bare one. Cytotoxicity study up to 2 mg mL-1 concentration showed no drastic change in cell viability of nanoparticles after coating. Also, coated nanoparticles showed increased SAR value, making them suitable for hyperthermia therapy application.

  11. Mesoporous core-shell TiO(2) walnuts for photocatalysts and photodetectors with improved performances.

    PubMed

    He, Fei; Zhang, Chao; Zhou, Di; Cheng, Ling; Li, Tao; Li, Guangxing

    2014-05-28

    Mesoporous core-shell TiO2 walnuts (CSTWs) were successfully prepared by a facile one-step hydrothermal method. This superior micro-nanostructure endowed the sample with hierarchical mesopores and a high surface area of 90.97 m(2) g(-1). Their particle size, diameter and morphology could be readily controlled by varying the growth parameters. The influence of the glucose amount, the urea amount and the calcination temperature on the formation of microspheres was investigated. The formation mechanism of the mesoporous CSTWs was studied. The photocatalytic activity of CSTWs had been carried out by degradation of gaseous benzene. The results indicated that, compared with commercial TiO2 (Degussa P25), CSTWs exhibited significant photocatalytic activity. Moreover, the mesoporous CSTWs were also configured as high-performance photodetectors. When illuminated by UV light with a wavelength of 365 nm, the current was found to be significantly enhanced, and an IUV/Idark of about 500, a good rise time and decay time were obtained. PMID:24695865

  12. Improvement of advanced nodal method used in 3D core design system

    SciTech Connect

    Rauck, S.; Dall'Osso, A.

    2006-07-01

    This paper deals with AREVA NP progress in the modelling of neutronic phenomena, evaluated through 3D determinist core codes and using 2-group diffusion theory. Our report highlights the advantages of taking into account the assembly environment in the process used for the building of the 2-group collapsed neutronic parameters, such as cross sections or discontinuity factors. The interest of the present method, developed in order to account for the impact of the environment on the above mentioned parameters, resides (i) in the very definition of a global correlation between collapsed neutronic data calculated in an infinite medium and those calculated in a 3D-geometry, and (ii) in the use of a re-homogenization method. Using this approach, computations match better with actual measurements on control rod worth. They also present smaller differences on pin by pin power values compared to the ones computed with another code considered as a reference since it relies on multigroup transport theory. (authors)

  13. Laser Modified ZnO/CdSSe Core-Shell Nanowire Arrays for Micro-Steganography and Improved Photoconduction

    NASA Astrophysics Data System (ADS)

    Lu, Junpeng; Liu, Hongwei; Zheng, Minrui; Zhang, Hongji; Lim, Sharon Xiaodai; Tok, Eng Soon; Sow, Chorng Haur

    2014-09-01

    Arrays of ZnO/CdSSe core/shell nanowires with shells of tunable band gaps represent a class of interesting hybrid nanomaterials with unique optical and photoelectrical properties due to their type II heterojunctions and chemical compositions. In this work, we demonstrate that direct focused laser beam irradiation is able to achieve localized modification of the hybrid structure and chemical composition of the nanowire arrays. As a result, the photoresponsivity of the laser modified hybrid is improved by a factor of ~3. A 3D photodetector with improved performance is demonstrated using laser modified nanowire arrays overlaid with monolayer graphene as the top electrode. Finally, by controlling the power of the scanning focused laser beam, micropatterns with different fluorescence emissions are created on a substrate covered with nanowire arrays. Such a pattern is not apparent when imaged under normal optical microscopy but the pattern becomes readily revealed under fluorescence microscopy i.e. a form of Micro-Steganography is achieved.

  14. Laser modified ZnO/CdSSe core-shell nanowire arrays for Micro-Steganography and improved photoconduction.

    PubMed

    Lu, Junpeng; Liu, Hongwei; Zheng, Minrui; Zhang, Hongji; Lim, Sharon Xiaodai; Tok, Eng Soon; Sow, Chorng Haur

    2014-01-01

    Arrays of ZnO/CdSSe core/shell nanowires with shells of tunable band gaps represent a class of interesting hybrid nanomaterials with unique optical and photoelectrical properties due to their type II heterojunctions and chemical compositions. In this work, we demonstrate that direct focused laser beam irradiation is able to achieve localized modification of the hybrid structure and chemical composition of the nanowire arrays. As a result, the photoresponsivity of the laser modified hybrid is improved by a factor of ~3. A 3D photodetector with improved performance is demonstrated using laser modified nanowire arrays overlaid with monolayer graphene as the top electrode. Finally, by controlling the power of the scanning focused laser beam, micropatterns with different fluorescence emissions are created on a substrate covered with nanowire arrays. Such a pattern is not apparent when imaged under normal optical microscopy but the pattern becomes readily revealed under fluorescence microscopy i.e. a form of Micro-Steganography is achieved.

  15. Effect of the star formation histories on the SFR-M∗ relation at z ≥ 2

    NASA Astrophysics Data System (ADS)

    Cassarà, L. P.; Maccagni, D.; Garilli, B.; Scodeggio, M.; Thomas, R.; Le Fèvre, O.; Zamorani, G.; Schaerer, D.; Lemaux, B. C.; Cassata, P.; Le Brun, V.; Pentericci, L.; Tasca, L. A. M.; Vanzella, E.; Zucca, E.; Amorín, R.; Bardelli, S.; Castellano, M.; Cimatti, A.; Cucciati, O.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Paltani, S.; Ribeiro, B.; Sommariva, V.; Talia, M.; Tresse, L.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; de la Torre, S.; Dunlop, J.; Fotopoulou, S.; Guaita, L.; Koekemoer, A.; López-Sanjuan, C.; Mellier, Y.; Pforr, J.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2016-08-01

    We investigate the effect of different star formation histories (SFHs) on the relation between stellar mass (M∗) and star formation rate (SFR) using a sample of galaxies with reliable spectroscopic redshift zspec> 2 drawn from the VIMOS Ultra-Deep Survey (VUDS). We produce an extensive database of dusty model galaxies, calculated starting from a new library of single stellar population (SSPs) models, weighted by a set of 28 different star formation histories based on the Schmidt function, and characterized by different ratios of the gas infall timescale τinfall to the star formation efficiency ν. Dust extinction and re-emission were treated by means of the radiative transfer calculation. The spectral energy distribution (SED) fitting technique was performed by using GOSSIP+, a tool able to combine both photometric and spectroscopic information to extract the best value of the physical quantities of interest, and to consider the intergalactic medium (IGM) attenuation as a free parameter. We find that the main contribution to the scatter observed in the SFR-M∗ plane is the possibility of choosing between different families of SFHs in the SED fitting procedure, while the redshift range plays a minor role. The majority of the galaxies, at all cosmic times, are best fit by models with SFHs characterized by a high τinfall/ν ratio. We discuss the reliability of a low percentage of dusty and highly star-forming galaxies in the context of their detection in the far infrared (FIR).

  16. Improving Basic Skills in the Workplace. A Core Course for the Catering and Hospitality Industries.

    ERIC Educational Resources Information Center

    Collins, Lorraine

    This training pack is designed for use with employees in the catering and hospitality industries. The material takes common workplace procedures and terminology and uses these as the basis for improving reading, writing, oral communication, and math skills. The pack is designed as a complete course of 13 modules over a period of 32-48 hours, but…

  17. Targeted Delivery of Chemotherapeutic Agents Using Improved Radiosensitive Liquid Core Microcapsules and Assessment of Their Antitumor Effect

    SciTech Connect

    Harada, Satoshi Ehara, Shigeru; Ishii, Keizo; Yamazaki, Hiromichi; Matsuyama, Shigeo; Sato, Takahiro; Oikawa, Shyoichi; Kamiya, Tomihiro; Arakawa, Kazuo; Yokota, Wataru; Sera, Koichiro; Ito, Jyun

    2009-10-01

    Purpose: Radiation-sensitive microcapsules composed of alginate and hyaluronic acid are being developed. We report the development of improved microcapsules that were prepared using calcium- and yttrium-induced polymerization. We previously reported on the combined antitumor effect of carboplatin-containing microcapsules and radiotherapy. Methods and Materials: We mixed a 0.1% (wt/vol) solution of hyaluronic acid with a 0.2% alginate solution. Carboplatin (l mg) and indocyanine green (12.5 {mu}g) were added to this mixture, and the resultant material was used for capsule preparation. The capsules were prepared by spraying the material into a mixture containing a 4.34% CaCl{sub 2} solution supplemented with 0-0.01% yttrium. These capsules were irradiated with single doses of 0.5, 1.0, 1.5, or 2 Gy {sup 60}Co {gamma}-rays. Immediately after irradiation, the frequency of microcapsule decomposition was determined using a microparticle-induced X-ray emission camera. The amount of core content released was estimated by particle-induced X-ray emission and colorimetric analysis with 0.25% indocyanine green. The antitumor effect of the combined therapy was determined by monitoring its effects on the diameter of an inoculated Meth A fibrosarcoma. Results: Microcapsules that had been polymerized using a 4.34% CaCl{sub 2} solution supplemented with 5.0 x 10{sup -3}% (10{sup -3}% meant or 10%{sup -3}) yttrium exhibited the maximal decomposition, and the optimal release of core content occurred after 2-Gy irradiation. The microcapsules exhibited a synergistic antitumor effect combined with 2-Gy irradiation and were associated with reduced adverse effects. Conclusion: The results of our study have shown that our liquid core microcapsules can be used in radiotherapy for targeted delivery of chemotherapeutic agents.

  18. An improved multipole approximation for self-gravity and its importance for core-collapse supernova simulations

    SciTech Connect

    Couch, Sean M.; Graziani, Carlo; Flocke, Norbert

    2013-12-01

    Self-gravity computation by multipole expansion is a common approach in problems such as core-collapse and Type Ia supernovae, where single large condensations of mass must be treated. The standard formulation of multipole self-gravity in arbitrary coordinate systems suffers from two significant sources of error, which we correct in the formulation presented in this article. The first source of error is due to the numerical approximation that effectively places grid cell mass at the central point of the cell, then computes the gravitational potential at that point, resulting in a convergence failure of the multipole expansion. We describe a new scheme that avoids this problem by computing gravitational potential at cell faces. The second source of error is due to sub-optimal choice of location for the expansion center, which results in angular power at high multipole l values in the gravitational field, requiring a high—and expensive—value of multipole cutoff l {sub max}. By introducing a global measure of angular power in the gravitational field, we show that the optimal coordinate for the expansion is the square-density-weighted mean location. We subject our new multipole self-gravity algorithm, implemented in the FLASH simulation framework, to two rigorous test problems: MacLaurin spheroids for which exact analytic solutions are known, and core-collapse supernovae. We show that key observables of the core-collapse simulations, particularly shock expansion, proto-neutron star motion, and momentum conservation, are extremely sensitive to the accuracy of the multipole gravity, and the accuracy of their computation is greatly improved by our reformulated solver.

  19. An Improved Multipole Approximation for Self-gravity and Its Importance for Core-collapse Supernova Simulations

    NASA Astrophysics Data System (ADS)

    Couch, Sean M.; Graziani, Carlo; Flocke, Norbert

    2013-12-01

    Self-gravity computation by multipole expansion is a common approach in problems such as core-collapse and Type Ia supernovae, where single large condensations of mass must be treated. The standard formulation of multipole self-gravity in arbitrary coordinate systems suffers from two significant sources of error, which we correct in the formulation presented in this article. The first source of error is due to the numerical approximation that effectively places grid cell mass at the central point of the cell, then computes the gravitational potential at that point, resulting in a convergence failure of the multipole expansion. We describe a new scheme that avoids this problem by computing gravitational potential at cell faces. The second source of error is due to sub-optimal choice of location for the expansion center, which results in angular power at high multipole l values in the gravitational field, requiring a high—and expensive—value of multipole cutoff l max. By introducing a global measure of angular power in the gravitational field, we show that the optimal coordinate for the expansion is the square-density-weighted mean location. We subject our new multipole self-gravity algorithm, implemented in the FLASH simulation framework, to two rigorous test problems: MacLaurin spheroids for which exact analytic solutions are known, and core-collapse supernovae. We show that key observables of the core-collapse simulations, particularly shock expansion, proto-neutron star motion, and momentum conservation, are extremely sensitive to the accuracy of the multipole gravity, and the accuracy of their computation is greatly improved by our reformulated solver.

  20. Modifications to WRF’s dynamical core to improve the treatment of moisture for large­-eddy simulations

    SciTech Connect

    Xiao, Heng; Endo, Satoshi; Wong, May Ws; Skamarock, W.; Klemp, Joseph B.; Fast, Jerome D.; Gustafson, William I.; Vogelmann, A. M.; Wang, Hailong; Liu, Yangang; Lin, Wuyin

    2015-10-29

    Yamaguchi and Feingold (2012) note that the cloud fields in their Weather Research and Forecasting (WRF) large-eddy simulations (LESs) of marine stratocumulus exhibit a strong sensitivity to time stepping choices. In this study, we reproduce and analyze this sensitivity issue using two stratocumulus cases, one marine and one continental. Results show that (1) the sensitivity is associated with spurious motions near the moisture jump between the boundary layer and the free atmosphere, and (2) these spurious motions appear to arise from neglecting small variations in water vapor mixing ratio (qv) in the pressure gradient calculation in the acoustic sub­stepping portion of the integration procedure. We show that this issue is remedied in the WRF dynamical core by replacing the prognostic equation for the potential temperature θ with one for the moist potential temperature θm=θ(1+1.61qv), which allows consistent treatment of moisture in the calculation of pressure during the acoustic sub­steps. With this modification, the spurious motions and the sensitivity to the time stepping settings (i.e., the dynamic time step length and number of acoustic sub­steps) are eliminated in both of the example stratocumulus cases. This modification improves the applicability of WRF for LES applications, and possibly other models using similar dynamical core formulations, and also permits the use of longer time steps than in the original code.

  1. Novel copper (Cu) loaded core-shell silica nanoparticles with improved Cu bioavailability: synthesis, characterization and study of antibacterial properties.

    PubMed

    Maniprasad, Pavithra; Santra, Swadeshmukul

    2012-08-01

    We report synthesis of a novel core-shell silica based antimicrobial nanoparticles where the silica shell has been engineered to accommodate copper (Cu). Synthesis of the core-shell Cu-silica nanoparticle (C-S CuSiO2NP) involves preparation of base-hydrolyzed Stöber silica "seed" particles first, followed by the acid-catalyzed seeded growth of the Cu-silica shell layer around the core. The Scanning Electron Microscopy (SEM) and the Transmission Electron Microscopy (TEM) measured the seed particle size to be -380 nm and the shell thickness to be -35 nm. The SEM particle characterization confirms formation of highly monodispersed particles with smooth surface morphology. Characterization of particle size distribution in solution by Dynamic Light Scattering (DLS) technique was fairly consistent with the electron microscopy results. Loading of Cu to nanoparticles was confirmed by the SEM-Energy Dispersive X-Ray Spectroscopy (EDS) and Atomic Absorption Spectroscopy (AAS). The Cu loading was estimated to be 0.098 microg of metallic copper per mg of C-S CuSiO2NP material by the AAS technique. Antibacterial efficacy of C-S CuSiO2NP was evaluated against E. coli and B. subtilis using Cu hydroxide ("Insoluble" Cu compound, sub-micron size particles) as positive control and silica "seed" particles (without Cu loading) as negative control. Bacterial growth in solution was measured against different concentrations of C-S CuSiO2NP to determine the Minimum Inhibitory Concentration (MIC) value. The estimated MIC values were 2.4 microg metallic Cu/mL for both E. coli and B. subtilis. Bac-light fluorescence microscopy based assay was used to count relative population of the live and dead bacteria cells. Antibacterial study clearly shows that C-S CuSiO2NP is more effective than insoluble Cu hydroxide particles at equivalent metallic Cu concentration, suggesting improvement of Cu bioavailability (i.e., more soluble Cu) in C-SCuSiO2NP material due to its core-shell design. PMID

  2. Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity

    SciTech Connect

    Levitas, Valery I.; McCollum, Jena; Pantoya, Michelle L.; Tamura, Nobumichi

    2015-09-07

    Dilatation of aluminum (Al) core for micron-scale particles covered by alumina (Al{sub 2}O{sub 3}) shell was measured utilizing x-ray diffraction with synchrotron radiation for untreated particles and particles after annealing at 573 K and fast quenching at 0.46 K/s. Such a treatment led to the increase in flame rate for Al + CuO composite by 32% and is consistent with theoretical predictions based on the melt-dispersion mechanism of reaction for Al particles. Experimental results confirmed theoretical estimates and proved that the improvement of Al reactivity is due to internal stresses. This opens new ways of controlling particle reactivity through creating and monitoring internal stresses.

  3. Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity

    NASA Astrophysics Data System (ADS)

    Levitas, Valery I.; McCollum, Jena; Pantoya, Michelle L.; Tamura, Nobumichi

    2015-09-01

    Dilatation of aluminum (Al) core for micron-scale particles covered by alumina (Al2O3) shell was measured utilizing x-ray diffraction with synchrotron radiation for untreated particles and particles after annealing at 573 K and fast quenching at 0.46 K/s. Such a treatment led to the increase in flame rate for Al + CuO composite by 32% and is consistent with theoretical predictions based on the melt-dispersion mechanism of reaction for Al particles. Experimental results confirmed theoretical estimates and proved that the improvement of Al reactivity is due to internal stresses. This opens new ways of controlling particle reactivity through creating and monitoring internal stresses.

  4. Star Formation in the Local Universe from the CALIFA sample: calibration and contribution of disks to the SFR density

    NASA Astrophysics Data System (ADS)

    Catalán-Torrecilla, Cristina; Gil de Paz, Armando; Castillo-Morales, África; Iglesias-Páramo, Jorge; Sánchez, Sebastián F.

    2015-02-01

    The study of the star formation rate (SFR) is crucial for understanding the birth and evolution of the galaxies (Kennicutt 1998), with this aim in mind, we make use of a well-characterized sample of 380 nearby galaxies from the CALIFA survey that fill the entire color-magnitude diagram in the Local Universe. The availability of wide-field CALIFA IFS ensures a proper determination of the underlying stellar continuum and, consequently, of the extiction-corrected Hα luminosity. We compare our integrated Hα-based SFRs with single and hybrids tracers at other wavelengths found in the literature (Calzetti 2013). Then, we provide a new set of single-band and hybrid calibrators anchored to the extinction-corrected Hα luminosities. In the case of the hybrid calibrators we determine the best fitting aIR coefficients for different combinations of observed (UV or Hα) and dust-reprocessed (22μm or TIR) SFR contributions (where SFR ~ Lobs + aIR × L[IR]). This analysis allow us to provide, for the first time, a set of hybrid calibrations for different morphological types and masses. These are particularly useful in case that the sample to be analyzed shows a different bias in terms of morphology or, more commonly, luminosity or stellar mass. We also study the dependence of this coefficient with color and ionized-gas attenuation. The distributions of a IR values are quite wide in all cases. We found that not single physical property can by itself explain the variation found in a IR. Finally, we explore the spatial distribution of the SFR by measuring the contribution of disks to the total SFR in the Local Universe. Our preliminary spatially-resolved analysis shows that the disk to total (disk + spheroidal component) SFR ratio is on average ~ 88%. The use of the 2D spectroscopic data is critical to properly determine the Hα luminosity function and SFR density in the Local Universe per galaxy components, the ultimate goal of this project.

  5. Laser Modified ZnO/CdSSe Core-Shell Nanowire Arrays for Micro-Steganography and Improved Photoconduction

    PubMed Central

    Lu, Junpeng; Liu, Hongwei; Zheng, Minrui; Zhang, Hongji; Lim, Sharon Xiaodai; Tok, Eng Soon; Sow, Chorng Haur

    2014-01-01

    Arrays of ZnO/CdSSe core/shell nanowires with shells of tunable band gaps represent a class of interesting hybrid nanomaterials with unique optical and photoelectrical properties due to their type II heterojunctions and chemical compositions. In this work, we demonstrate that direct focused laser beam irradiation is able to achieve localized modification of the hybrid structure and chemical composition of the nanowire arrays. As a result, the photoresponsivity of the laser modified hybrid is improved by a factor of ~3. A 3D photodetector with improved performance is demonstrated using laser modified nanowire arrays overlaid with monolayer graphene as the top electrode. Finally, by controlling the power of the scanning focused laser beam, micropatterns with different fluorescence emissions are created on a substrate covered with nanowire arrays. Such a pattern is not apparent when imaged under normal optical microscopy but the pattern becomes readily revealed under fluorescence microscopy i.e. a form of Micro-Steganography is achieved. PMID:25213321

  6. On the effect of different placing ZrH moderator material on the performance of a SFR core

    SciTech Connect

    Merk, B.; Weiss, F. P.

    2012-07-01

    This study describes the development of a sodium fast reactor fuel assembly design with reduced void reactivity coefficient, achieved through the use of the ZrH moderating material. In the study the sodium void effect, as well as the major feedback coefficients are analyzed. Besides the feedback coefficients, the influence on the operational parameters like neutron flux distribution, power distribution, and burnup distribution is investigated for the different possibilities of arranging the moderating material in the fuel assembly. Additionally, the fuel cycle parameters - breeding and minor actinide production - are analyzed. For a first evaluation of the behavior during transients the influence of temperature changes in the ZrH is studied. (authors)

  7. Enhanced X-ray emission from Lyman break analogues and a possible LX-SFR-metallicity plane

    NASA Astrophysics Data System (ADS)

    Brorby, M.; Kaaret, P.; Prestwich, A.; Mirabel, I. F.

    2016-04-01

    The source of energetic photons that heated and reionized the early Universe remains uncertain. Early galaxies had low metallicity and recent population synthesis calculations suggest that the number and luminosity of high-mass X-ray binaries are enhanced in star-forming galaxies with low metallicity, offering a potentially important and previously overlooked source of heating and reionization. Lyman break analogue (LBA) galaxies are local galaxies that strongly resemble the high-redshift, star-forming Lyman break galaxies and have been suggested as local analogues to these metal-deficient galaxies found in the early Universe. We studied a sample of 10 LBAs in order to measure the relation between star formation rate and X-ray luminosity. We found that for LBAs with metallicities in the range 12 + log10(O/H) = 8.15-8.80, the LX -SFR relation was log _{10} (L_X/SFR {[erg s^{-1} M_{⊙}^{-1} yr]}) = 39.85(± 0.10) in the 0.5-8 keV band with a dispersion of σ = 0.25 dex. This is an enhancement of nearly a factor of 2 in the L0.5-8 keV-SFR relation relative to results for nearby, near-solar metallicity galaxies. The enhancement is significant at the 98.2 per cent level (2.4σ). Our enhanced LX/SFR relation is consistent with the metallicity-dependent predicted value from population synthesis models. We discuss the possibility of an LX-SFR-metallicity plane for star-forming galaxies. These results are important to our understanding of reionization and the formation of early galaxies.

  8. Enhanced exchange bias and improved ferromagnetic properties in Permalloy-BiFe0.95Co0.05O3 core-shell nanostructures

    NASA Astrophysics Data System (ADS)

    Javed, K.; Li, W. J.; Ali, S. S.; Shi, D. W.; Khan, U.; Riaz, S.; Han, X. F.

    2015-12-01

    Hybrid core-shell nanostructures consisting of permalloy (Ni80Fe20) and multiferroic(BiFeO3, BFO/BiFe0.95Co0.05O3, BFC) materials were synthesized by a two-step method, based on wet chemical impregnation and subsequent electrodeposition within porous alumina membranes. Structural and magnetic characterizations have been done to investigate doping effect on magnetic properties and exchange bias. The magnetometry analysis revealed significant enhancements of the exchange bias and coercivity in NiFe-BFC core-shell nanostructures as compared with NiFe-BFO core-shell nanostructures. The enhancements can be attributed to the effective reduction of ferromagnet domain sizes between adjacent layers of core-shell structure. It indicates that it is possible to improve properties of multiferroic composites by site-engineering method. Our approach opens a pathway to obtain optimized nanostructured multiferroic composites exhibiting tunable magnetic properties.

  9. Improving femtosecond laser pulse delivery through a hollow core photonic crystal fiber for temporally focused two-photon endomicroscopy

    PubMed Central

    Choi, Heejin; So, Peter T. C.

    2014-01-01

    In this paper, we present a strategy to improve delivery of femtosecond laser pulses from a regenerative amplifier through a hollow core photonic crystal fiber for temporally focused wide-field two-photon endomicroscopy. For endomicroscope application, wide-field two-photon excitation has the advantage of requiring no scanning in the distal end. However, wide-field two-photon excitation requires peak power that is 104–105 times higher than the point scanning approach corresponding to femtosecond pulses with energy on the order of 1–10 μJ at the specimen plane. The transmission of these high energy pulses through a single mode fiber into the microendoscope is a significant challenge. Two approaches were pursued to partially overcome this limitation. First, a single high energy pulse is split into a train of pulses with energy below the fiber damage threshold better utilizing the available laser energy. Second, stretching the pulse width in time by introducing negative dispersion was shown to have the dual benefit of reducing fiber damage probability and compensating for the positive group velocity dispersion induced by the fiber. With these strategy applied, 11 fold increase in the two photon excitation signal has been demonstrated. PMID:25316120

  10. Review of fuel/cladding eutectic formation in metallic SFR fuel pins

    SciTech Connect

    Denman, M.; Todreas, N.; Driscoll, M.

    2012-07-01

    Sodium-cooled Fast Reactors (SFRs) remain a strong contender amongst the Generation IV reactor concepts. Metallic fuel has been a primary fuel option for SFR designers in the US and was used extensively in the first generation of SFRs. One of the benefits of metallic fuel is its chemical compatibility with the coolant; unfortunately this compatibility does not extend to steel cladding at elevated temperatures. It has been known that uranium, plutonium, and rare earths diffuse with cladding constituents to form a low melting point fuel/cladding eutectic which acts to thin the cladding once the interfacial temperature rises above the system liquidus temperature. Since the 1960's, many experiments have been performed and published to evaluate the rate of fuel/cladding eutectic formation and the temperature above which melting will begin as a function of fuel/cladding interfacial temperature, time at temperature, fuel constituents (uranium, fissium or uranium (plutonium) zirconium), cladding type (stainless steel 316, stainless steel 306, D9 or HT9), beginning of life linear power, plutonium enrichment and burnup. The results of these tests, however, remain scattered across conference and journal papers spanning 50 years. The tests used to collect this data also varied in experimental procedure throughout the years. This paper will consolidate the experimental data into four groups of similar test conditions and expand upon the testing performed for each group in detail. A companion paper in PSA 2011 will discuss predictive correlations formulated from this database. (authors)

  11. MODFLOW-LGR-Modifications to the streamflow-routing package (SFR2) to route streamflow through locally refined grids

    USGS Publications Warehouse

    Mehl, Steffen W.; Hill, Mary C.

    2011-01-01

    This report documents modifications to the Streamflow-Routing Package (SFR2) to route streamflow through grids constructed using the multiple-refined-areas capability of shared node Local Grid Refinement (LGR) of MODFLOW-2005. MODFLOW-2005 is the U.S. Geological Survey modular, three-dimensional, finite-difference groundwater-flow model. LGR provides the capability to simulate groundwater flow by using one or more block-shaped, higher resolution local grids (child model) within a coarser grid (parent model). LGR accomplishes this by iteratively coupling separate MODFLOW-2005 models such that heads and fluxes are balanced across the shared interfacing boundaries. Compatibility with SFR2 allows for streamflow routing across grids. LGR can be used in two- and three-dimensional, steady-state and transient simulations and for simulations of confined and unconfined groundwater systems.

  12. Performance of supercritical CO{sub 2} Brayton cycle with additive gases at varying critical points for SFR application

    SciTech Connect

    Jeong, W. S.; Jeong, Y. H.

    2012-07-01

    The supercritical carbon dioxide Brayton cycle (S-CO{sub 2} cycle) has received attention as alternative to the energy conversion system for a Sodium-cooled Fast Reactor (SFR). The high cycle efficiency of S-CO{sub 2} cycle is attributed to significantly reduced compressor work. This is because the compressor operates like a pump in the vicinity of CO{sub 2} critical point. To make use of this feature, the minimum cycle operating range of S-CO{sub 2} cycle, which is the main compressor inlet condition, should be located close to the critical point of CO{sub 2}. This translated into that the critical point of CO{sub 2} is the limitation of the lowest cycle condition of S-CO{sub 2} cycles. To increase the flexibility and broaden the applicability of the cycle, changing the critical point of CO{sub 2} by mixing additive gases could be adopted. An increase in the efficiency of the S-CO{sub 2} cycle could be achieved by decreasing critical point of CO{sub 2}. In addition, increasing critical point of CO{sub 2} could be utilized to obtain improved cycle performances at ascending heat sink temperature of hot arid areas. Due to the rapid fluctuations of thermo-physical properties of gas mixtures near the critical point, an in-house cycle analysis code coupled to NIST property database was developed. Several gases were selected as potential additives through the screening process for thermal stability and chemical interaction with sodium. By using the developed cycle code, optimized cycles of each gas mixture were compared with the reference case of S-CO{sub 2} cycle. For decreased critical temperatures, CO{sub 2}-Xe and CO{sub 2}-Kr showed an increase in the total cycle efficiency. At increasing critical temperatures, the performance of CO{sub 2}-H{sub 2}S and CO{sub 2}-cyclohexane is superior to S-CO{sub 2}cycle when the compressor inlet temperature is above the critical temperature of CO{sub 2}. (authors)

  13. Improved stratigraphic dating at a low accumulation Alpine ice core through laser ablation trace element profiling at sub-mm depth resolution

    NASA Astrophysics Data System (ADS)

    Bohleber, Pascal; Spaulding, Nicole; Mayewski, Paul; Sneed, Sharon; Handley, Mike; Erhardt, Tobias; Wagenbach, Dietmar

    2015-04-01

    The small scale Colle Gnifetti glacier saddle (4450 m asl, Monte Rosa region) is the only ice core drilling site in the European Alps with a net accumulation low enough to offer multi-millennia climate records. However, a robust interpretation of such long term records (i.e. mineral dust, stable water isotopes) at the Colle Gnifetti (CG) multi core array is strongly challenged by depositional noise associated with a highly irregular annual layer stratigraphy. In combination with a relatively large vertical strain rate and rapid layer thinning, annual layer counting gets increasingly ambiguous as of approximately 100 years. In addition, this prevents clear attribution of likely volcanic horizons to historical eruption dates. To improve stratigraphic dating under such intricate conditions, we deployed laser ablation (LA) ICP-MS at sub-mm sample resolution. We present here the first LA impurity profiles from a new Colle Gnifetti ice core drilled 73 m to bedrock in 2013 at a site where the net snow accumulation is around 20 cm w.e. per year. We contrast the LA signal variability (including Ca, Fe, Na) to continuous flow analyses (CFA) records at cm-resolution (Ca, Na, melt water conductivity, micro- particle) recorded over the whole core length. Of special concern are the lower 28 m to bedrock, which have been continuously profiled in LA Ca, thus offering the direct comparison of Ca-signals between CFA and LA. By this means, we first validate at upper depths LA based annual layer identification through agreement with CFA based counting efforts before demonstrating the LA based counting still works at depths where CFA derived annual layers become spurious since embedded in strong, multi-year cycles. Finally, LA ice core profiling of our CG core has potential for not only dating improvement but also reveals benefits in resolving highly thinned basal ice sections including accounting for micro-structural features such as grain boundaries.

  14. Mapping the average AGN accretion rate in the SFR-M* plane for Herschel-selected galaxies at 0 < z ≤ 2.5

    NASA Astrophysics Data System (ADS)

    Delvecchio, I.; Lutz, D.; Berta, S.; Rosario, D. J.; Zamorani, G.; Pozzi, F.; Gruppioni, C.; Vignali, C.; Brusa, M.; Cimatti, A.; Clements, D. L.; Cooray, A.; Farrah, D.; Lanzuisi, G.; Oliver, S.; Rodighiero, G.; Santini, P.; Symeonidis, M.

    2015-05-01

    We study the relation of AGN accretion, star formation rate (SFR) and stellar mass (M*) using a sample of ≈8600 star-forming galaxies up to z = 2.5 selected with Herschel imaging in the GOODS and COSMOS fields. For each of them we derive SFR and M*, both corrected, when necessary, for emission from an active galactic nucleus (AGN), through the decomposition of their spectral energy distributions (SEDs). About 10 per cent of the sample are detected individually in Chandra observations of the fields. For the rest of the sample, we stack the X-ray maps to get average X-ray properties. After subtracting the X-ray luminosity expected from star formation and correcting for nuclear obscuration, we derive the average AGN accretion rate for both detected sources and stacks, as a function of M*, SFR and redshift. The average accretion rate correlates with SFR and with M*. The dependence on SFR becomes progressively more significant at z > 0.8. This may suggest that SFR is the original driver of these correlations. We find that average AGN accretion and star formation increase in a similar fashion with offset from the star-forming `main-sequence'. Our interpretation is that accretion on to the central black hole and star formation broadly trace each other, irrespective of whether the galaxy is evolving steadily on the main-sequence or bursting.

  15. Surface Modification of PMMA to Improve Adhesion to Corneal Substitutes in a Synthetic Core-Skirt Keratoprosthesis.

    PubMed

    Riau, Andri K; Mondal, Debasish; Yam, Gary H F; Setiawan, Melina; Liedberg, Bo; Venkatraman, Subbu S; Mehta, Jodhbir S

    2015-10-01

    Patients with advanced corneal disease do poorly with conventional corneal transplantation and require a keratoprosthesis (KPro) for visual rehabilitation. The most widely used KPro is constructed using poly(methyl methacrylate) (PMMA) in the central optical core and a donor cornea as skirt material. In many cases, poor adherence between the PMMA and the soft corneal tissue is responsible for device "extrusion" and bacterial infiltration. The interfacial adhesion between the tissue and the PMMA was therefore critical to successful implantation and device longevity. In our approach, we modified the PMMA surface using oxygen plasma (plasma group); plasma followed by calcium phosphate (CaP) coating (p-CaP); dopamine followed by CaP coating (d-CaP); or plasma followed by coating with (3-aminopropyl)triethoxysilane (3-APTES). To create a synthetic KPro model, we constructed and attached 500 μm thick collagen type I hydrogel on the modified PMMA surfaces. Surface modifications produced significantly improved interfacial adhesion strength compared to untreated PMMA (p < 0.001). The p-CaP group yielded the best interfacial adhesion with the hydrogel (177 ± 27 mN/cm(2)) followed by d-CaP (168 ± 31 mN/cm(2)), 3-APTES (145 ± 12 mN/cm(2)), and plasma (119 ± 10 mN/cm(2)). Longer-term stability of the adhesion was achieved by d-CaP, which, after 14 and 28 days of incubation in phosphate buffered saline, yielded 164 ± 25 mN/cm(2) (p = 0.906 compared to adhesion at day 1) and 131 ± 20 mN/cm(2) (p = 0.053), respectively. In contrast, significant reduction of adhesion strength was observed in p-CaP group over time (p < 0.001). All surface coatings were biocompatible to human corneal stromal fibroblasts, except for the 3-APTES group, which showed no live cells at 72 h of culture. In contrast, cells on d-CaP surface showed good anchorage, evidenced by the expression of focal adhesion complex (paxillin and vinculin), and prominent filopodia protrusions. In conclusion, d-CaP can

  16. Optimizing LiFePO₄@C core-shell structures via the 3-aminophenol-formaldehyde polymerization for improved battery performance.

    PubMed

    Chi, Zi-xiang; Zhang, Wei; Wang, Xu-sheng; Cheng, Fu-quan; Chen, Ji-tao; Cao, An-min; Wan, Li-jun

    2014-12-24

    Polyanion-type cathode materials are well-known for their low electronic conductivity; accordingly, the addition of conductive carbon in the cathode materials becomes an indispensable step for their application in lithium ion batteries. To maximize the contribution of carbon, a core-shell structure with a full coverage of carbon should be favorable due to an improved electronic contact between different particles. Here, we report the formation of a uniform carbon nanoshell on a typical cathode material, LiFePO4, with the shell thickness precisely defined via the 3-aminophenol-formaldehyde polymerization process. In addition to the higher discharge capacity and the improved rate capability as expected from the carbon nanoshell, we identified that the core-shell configuration could lead to a much safer cathode material as revealed by the obviously reduced iron dissolution, much less heat released during the cycling, and better cyclability at high temperature.

  17. Determining the stable isotope composition of pore water from saturated and unsaturated zone core: improvements to the direct vapour equilibration laser spectrometry method

    NASA Astrophysics Data System (ADS)

    Hendry, M. J.; Schmeling, E.; Wassenaar, L. I.; Barbour, S. L.; Pratt, D.

    2015-11-01

    A method to measure the δ2H and δ18O composition of pore waters in saturated and unsaturated geologic core samples using direct vapour equilibration and laser spectrometry (DVE-LS) was first described in 2008, and has since been rapidly adopted. Here, we describe a number of important methodological improvements and limitations encountered in routine application of DVE-LS over several years. Generally, good comparative agreement, as well as accuracy, is obtained between core pore water isotopic data obtained using DVE-LS and that measured on water squeezed from the same core. In complex hydrogeologic settings, high-resolution DVE-LS depth profiles provide greater spatial resolution of isotopic profiles compared to long-screened or nested piezometers. When fluid is used during drilling and coring (e.g. water rotary or wet sonic drill methods), spiking the drill fluid with 2H can be conducted to identify core contamination. DVE-LS analyses yield accurate formational isotopic data for fine-textured core (e.g. clay, shale) samples, but are less effective for cores obtained from saturated permeable (e.g. sand, gravels) geologic media or on chip samples that are easily contaminated by wet rotary drilling fluid. Data obtained from DVE-LS analyses of core samples collected using wet (contamination by drill water) and dry sonic (water loss by heating) methods were also problematic. Accurate DVE-LS results can be obtained on core samples with gravimetric water contents > 5 % by increasing the sample size tested. Inexpensive Ziploc™ gas-sampling bags were determined to be as good as, if not better than, other, more expensive specialty bags. Sample storage in sample bags provides acceptable results for up to 10 days of storage; however, measurable water loss, as well as evaporitic isotopic enrichment, occurs for samples stored for up to 6 months. With appropriate care taken during sample collection and storage, the DVE-LS approach for obtaining high-resolution pore water

  18. Four-Strand Core Suture Improves Flexor Tendon Repair Compared to Two-Strand Technique in a Rabbit Model

    PubMed Central

    Beyersdoerfer, Sascha Tobias; Vollmar, Brigitte; Mittlmeier, Thomas; Gierer, Philip

    2016-01-01

    Introduction. This study was designed to investigate the influence of the amount of suture material on the formation of peritendinous adhesions of intrasynovial flexor tendon repairs. Materials and Methods. In 14 rabbits, the flexor tendons of the third and the fourth digit of the right hind leg were cut and repaired using a 2- or 4-strand core suture technique. The repaired tendons were harvested after three and eight weeks. The range of motion of the affected toes was measured and the tendons were processed histologically. The distance between the transected tendon ends, the changes in the peritendinous space, and cellular and extracellular inflammatory reaction were quantified by different staining. Results. A 4-strand core suture resulted in significantly less gap formation. The 2-strand core suture showed a tendency to less adhesion formation. Doubling of the intratendinous suture material was accompanied by an initial increase in leukocyte infiltration and showed a greater amount of formation of myofibroblasts. From the third to the eighth week after flexor tendon repair, both the cellular and the extracellular inflammation decreased significantly. Conclusion. A 4-strand core suture repair leads to a significantly better tendon healing process with less diastasis between the sutured tendon ends despite initially pronounced inflammatory response. PMID:27446949

  19. Examining the Effects of a National League for Nursing Core Competencies Workshop as an Intervention to Improve Nurse Faculty Practice

    ERIC Educational Resources Information Center

    VanBever Wilson, Robin R.

    2010-01-01

    Due to the complex challenges facing schools of nursing, a research study was implemented to introduce nurse faculty at one small rural northeastern Tennessee school of nursing to the NLN "Core Competencies for Nurse Educators". Utilizing Kalb's Nurse Faculty Self-Evaluation Tool as a pre- and post-intervention test, 30 nurse faculty members…

  20. Hematite homogeneous core/shell hierarchical spheres: Surfactant-free solvothermal preparation and their improved catalytic property of selective oxidation

    SciTech Connect

    Lian Suoyuan; Li Haitao; He Xiaodie; Kang Zhenhui; Liu Yang; Lee, Shuit Tong

    2012-01-15

    Solvothermal synthesis is an efficient synthetic method for preparing nano and micromaterials. Preparation of hematite through alcoholysis of ferric ion under solvothermal condition has been carried out at low concentrations. In this paper, Fe{sub 2}O{sub 3} homogeneous core/shell hierarchical nanostructures were synthesized via solvothermal treatment of FeCl{sub 3}{center_dot}6H{sub 2}O and ethanol. The achievements of such structures can be attributed to two important factors: high temperature and high concentration. Besides, the crystal water and reaction time were also important factors to the synthesis of hematite. The prepared samples were characterized using X-ray powder diffraction, Raman spectra, scanning electron microscopy equipped with an energy-dispersive X-ray spectrometer, transmission electron microscopy and Brunauer-Emmett-Teller surface area and pore size distribution. X-ray photoelectron spectroscopy showed a satellite peak at 719.8 eV, which is the characteristic peak of Fe(III). The formation mechanism of the spheres and the effects of the reactant concentrations and reaction temperatures have been discussed. Moreover, the enhanced catalytic activity of the spheres has also been investigated through oxidation of benzyl alcohol to benzaldehyde with high conversion (42%) and selectivity (95%). - Graphical abstract: Fe{sub 2}O{sub 3} homogeneous core/shell hierarchical microspheres were synthesized by solvothermal method. Owing to the special structure, the synthesized Fe{sub 2}O{sub 3} microspheres exhibit a superior catalytic activity in benzyl oxidation. Highlights: Black-Right-Pointing-Pointer Hierarchical Fe{sub 2}O{sub 3} core/shell microspheres were synthesized. Black-Right-Pointing-Pointer Microspheres were assembled by {beta}-FeOOH. Black-Right-Pointing-Pointer The sample exhibits a superior catalytic activity and selectivity. Black-Right-Pointing-Pointer The high activity and selectivity are due to the hierarchical core/shell structure.

  1. The Gamma-Ray Bursts and Core-Collapse Supernovae - Global Star Forming Rate Peaks at Large Redshifts

    NASA Astrophysics Data System (ADS)

    Sokolov, V. V.

    2014-03-01

    This is a brief review on the first Gamma-Ray Bursts (GRB) optical identifications - GRB host galaxies and Star Forming Rate (SFR) at relatively small redshifts (z), on the metallicities of GRB hosts and the similarities and differences between GRB hosts and galaxies at larger z, and on the SFR and GRB rate (GRBR) at the high z. Evidences of a direct connection between long-duration GRBs and massive stars explosions (like Core-Collapse Super-Novae - CCSNe) are presented. Is there a fast decrease in SFR up to z ~10? Some unsolved problems related to GRBs are discussed: about the high-z GRB host galaxies, the high-z CCSN-GRB connection, and possible new crucial cosmological tests at high z.

  2. Improved L-C resonant decay technique for Q measurement of quasilinear power inductors: New results for MPP and ferrite powdered cores

    NASA Technical Reports Server (NTRS)

    Niedra, Janis M.; Gerber, Scott S.

    1995-01-01

    The L-C resonant decay technique for measuring circuit Q or losses is improved by eliminating the switch from the inductor-capacitor loop. A MOSFET switch is used instead to momentarily connect the resonant circuit to an existing voltage source, which itself is gated off during the decay transient. Very reproducible, low duty cycle data could be taken this way over a dynamic voltage range of at least 10:1. Circuit Q is computed from a polynomial fit to the sequence of the decaying voltage maxima. This method was applied to measure the losses at 60 kHz in inductors having loose powder cores of moly permalloy and an Mn-Zn power ferrite. After the copper and capacitor losses are separated out, the resulting specific core loss is shown to be roughly as expected for the MPP powder, but anomalously high for the ferrite powder. Possible causes are mentioned.

  3. Summary final report: Contract between the Japan atomic power company and the U.S. Department of Energy Improvement of core safety - study on GEM (III)

    SciTech Connect

    Burke, T.M.; Lucoff, D.M.

    1997-03-18

    This report provides a summary of activities associated with the technical exchange between representatives of the Japan Atomic Power Company (JAPC) and the United States Department of Energy (DOE) regarding the development and testing of Gas Expansion Modules (GEM) at the Fast Flux Test Facility (FFTF). Issuance of this report completes the scope of work defined in the original contract between JAPC and DOE titled ''Study on Improvement of Core Safety - Study on GEM (III).'' Negotiations related to potential modification of the contract are in progress. Under the proposed contract modification, DOE would provide an additional report documenting FFTF pump start tests with GEMs and answer additional JAPC questions related to core safety with and without GEMs.

  4. Young, Star-forming Galaxies and Their Local Counterparts: The Evolving Relationship of Mass-SFR-Metallicity Since z ˜ 2.1

    NASA Astrophysics Data System (ADS)

    Grasshorn Gebhardt, Henry S.; Zeimann, Gregory R.; Ciardullo, Robin; Gronwall, Caryl; Hagen, Alex; Bridge, Joanna S.; Schneider, Donald P.; Trump, Jonathan R.

    2016-01-01

    We explore the evolution of the Stellar Mass-Star Formation Rate (SFR)-Metallicity relation using a set of 256 COSMOS and GOODS galaxies in the redshift range 1.90 < z < 2.35. We present the galaxies’ rest-frame optical emission-line fluxes derived from IR-grism spectroscopy with the Hubble Space Telescope and combine these data with SFRs and stellar masses obtained from deep, multi-wavelength (rest-frame UV to IR) photometry. We then compare these measurements to those for a local sample of galaxies carefully matched in stellar mass (7.5≲ {log}({M}*/{M}⊙ )≲ 10.5) and SFR (-0.5≲ {log}({{SFR}})≲ 2.5 in M⊙ yr-1). We find that the distribution of z ˜ 2.1 galaxies in stellar mass-SFR-metallicity space is clearly different from that derived for our sample of similarly bright ({L}{{H}β }\\gt 3× {10}40 erg s-1) local galaxies, and this offset cannot be explained by simple systematic offsets in the derived quantities. At stellar masses above ˜ {10}9 {M}⊙ and SFRs above ˜ 10 {M}⊙ yr-1, the z ˜ 2.1 galaxies have higher oxygen abundances than their local counterparts, while the opposite is true for lower-mass, lower-SFR systems.

  5. One-Dimensional Analysis of Thermal Stratification in AHTR and SFR Coolant Pools

    SciTech Connect

    Haihua Zhao; Per F. Peterson

    2007-10-01

    Thermal stratification phenomena are very common in pool type reactor systems, such as the liquid-salt cooled Advanced High Temperature Reactor (AHTR) and liquid-metal cooled fast reactor systems such as the Sodium Fast Reactor (SFR). It is important to accurately predict the temperature and density distributions both for design optimation and accident analysis. Current major reactor system analysis codes such as RELAP5 (for LWR’s, and recently extended to analyze high temperature reactors), TRAC (for LWR’s), and SASSYS (for liquid metal fast reactors) only provide lumped-volume based models which can only give very approximate results and can only handle simple cases with one mixing source. While 2-D or 3-D CFD methods can be used to analyze simple configurations, these methods require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, yet such fine grid resolution is difficult or impossible to provide for studying the reactor response to transients due to computational expense. Therefore, new methods are needed to support design optimization and safety analysis of Generation IV pool type reactor systems. Previous scaling has shown that stratified mixing processes in large stably stratified enclosures can be described using one-dimensional differential equations, with the vertical transport by free and wall jets modeled using standard integral techniques. This allows very large reductions in computational effort compared to three-dimensional numerical modeling of turbulent mixing in large enclosures. The BMIX++ (Berkeley mechanistic MIXing code in C++) code was originally developed at UC Berkeley to implement such ideas. This code solves mixing and heat transfer problems in stably stratified enclosures. The code uses a Lagrangian approach to solve 1-D transient governing equations for the ambient fluid and uses analytical or 1-D integral models to compute substructures. By including liquid salt properties, BMIX++ code is

  6. Evolution of Intrinsic Scatter in the SFR-Stellar Mass Correlation at 0.5

    NASA Astrophysics Data System (ADS)

    Kurczynski, Peter; Gawiser, Eric J.; Acquaviva, Viviana; Rafelski, Marc; Teplitz, Harry I.; UVUDF Team, CANDELS Team

    2016-01-01

    We present observations of intrinsic scatter in the Star Formation Rate (SFR) - Stellar Mass (M*) correlation in the redshift range 0.5 < z < 3.0 and in the mass range 10^7 < M* < 10^11 Msun. We utilize photometry from the Hubble Ultradeep Field from the UDF12 and UVUDF campaigns and CANDELS/GOODS-S. By utilizing the exceptionally deep UDF photometry (e.g. F160W 29.9 AB, 5 sigma depth) and fitting the corresponding SEDs, we extend the SFR-M* correlation by a factor of 10-100X lower in M*. We detect galaxies down to M* approx 10^7 Msun, comparable to dwarf galaxies in the local universe. We find that the intrinsic scatter is relatively constant across the mass range, and in conflict with theoretical predictions, we do not find evidence for markedly increased scatter at low mass. We find a moderate increase in total and intrinsic scatter with time across the epoch of peak cosmic star formation. These findings are consistent with gradual assembly of stellar mass in galaxies as low as 10^7 Msun and star formation that is increasingly stochastic with cosmic time.

  7. Heat treatment of unclarified Escherichia coli homogenate improved the recovery efficiency of recombinant hepatitis B core antigen.

    PubMed

    Ng, Michelle Y T; Tan, Wen Siang; Abdullah, Norhafizah; Ling, Tau Chuan; Tey, Beng Ti

    2006-10-01

    Heat precipitation procedure has been regularly incorporated as a selective purification step in various thermostable proteins expressed in different hosts. This method is efficient in precipitation of most of the host proteins and also deactivates various host proteases that can be harmful to the desired gene products. In this study, introduction of heat treatment procedure in the purification of hepatitis B core antigen (HBcAg) produced in Escherichia coli has been investigated. Thermal treatment of the cell homogenate at 60 degrees C for 30 min prior to subsequent clarification steps has resulted in 1.4 times and 18% higher in purity and recovery yield, respectively, compared to the non-heat-treated cell homogenate. In direct capture of HBcAg by using anion-exchangers from unclarified feedstock, pre-conditioning the feedstock by heat treatment at 60 degrees C for 45 min has increased the recovery yield of HBcAg by 2.9-fold and 42% in purity compared to that treated for 10 min. Enzyme-linked immunosorbent assay (ELISA) analysis showed that the antigenicity of the core particles was not affected by the heat treatment process. PMID:16860402

  8. Using Water Vapor Isotope Observations from above the Greenland Ice Sheet to improve the Interpretation of Ice Core Water Stable Isotope Records

    NASA Astrophysics Data System (ADS)

    Steen-Larsen, H. C.; Masson-Delmotte, V.; Risi, C. M.; Yoshimura, K.; Werner, M.; Butzin, M.; Brun, E.; Landais, A.; Bonne, J. L.; Dahl-Jensen, D.

    2014-12-01

    Water stable isotope data from Greenland ice cores provide key paleoclimatic information. For the purpose of improving the climatic interpretation from ice core records, a monitoring of the isotopic composition δ18O and δD at several height levels (up to 13 meter) of near-surface water vapor, precipitation and snow in the first 0.5 cm surface layer has been conducted during three summers (2010-2012) at NEEM, NW Greenland. We compare the observed water vapor isotopic composition with model outputs from three isotope-enabled general circulation models: LMDZiso, isoGSM, ECHAM-wiso. This allows us to benchmark the models and address effect of model resolution, effect of transport, effect of isotope parameterization, and representation of significant source region contributions. We find for all models that the simulated isotopic value δD are significantly biased towards too enriched values. A bias, which is only partly explained by the air temperature. The simulated amplitude in d-excess variations is ~50% smaller than observed and the simulated average summer level is ~10‰ lower than in observations. Using back trajectories we observe water vapor of Arctic origin to have a high d-excess fingerprint. This fingerprint is not observed in the GCMiso simulations indicating a problem of simulating accurately the Arctic hydrological cycle. The bias in the simulated δD and d-excess water vapor is similar to the already-documented bias in the simulated δD and d-excess of Greenland ice core records. This suggests that if we improve the simulation of the water vapor isotopic composition we might also improve the simulation of the ice core isotope record. During periods between precipitation events, our data demonstrate parallel changes of δ18O and d-excess in surface snow and near-surface vapor. The changes in δ18O of the vapor are similar or larger than those of the snow δ18O. It is estimated using the CROCUS snow model that 6 to 20% of the surface snow mass is

  9. Improving Response to Foodborne Disease Outbreaks in the United States: Findings of the Foodborne Disease Centers for Outbreak Response Enhancement (FoodCORE), 2010–2012

    PubMed Central

    Biggerstaff, Gwen

    2015-01-01

    Context Each year foodborne diseases (FBD) affect approximately 1 in 6 Americans, resulting in 128,000 hospitalizations and 3,000 deaths. Decreasing resources impact the ability of public health officials to identify, respond to, and control FBD outbreaks. Geographically dispersed outbreaks necessitate multijurisdictional coordination across all levels of the public health system. Rapid response depends on rapid detection. Objective Targeted resources were provided to state and local health departments to improve completeness and timeliness of laboratory, epidemiology, and environmental health (EH) activities for FBD surveillance and outbreak response. Design Foodborne Disease Centers for Outbreak Response Enhancement (FoodCORE) centers, selected through competitive award, implemented work plans designed to make outbreak response more complete and faster in their jurisdiction. Performance metrics were developed and used to evaluate the impact and effectiveness of activities. Participants Departments of Health in Connecticut, New York City, Ohio, South Carolina, Tennessee, Utah, and Wisconsin. Results From the first year (Y1) of the program in October 2010 to the end of second year (Y2) in December 2012, the centers completed molecular subtyping for a higher proportion of Salmonella, Shiga toxin-producing E. coli, and Listeria (SSL) isolates (86% vs 98%) and reduced the average time to complete testing from a median of 8 to 4 days. The centers attempted epidemiologic interviews with more SSL case-patients (93% vs 99%) and the average time to attempt interviews was reduced from a median of 4 to 2 days. During Y2, nearly 200 EH assessments were conducted. FoodCORE centers began documenting model practices such as streamlining and standardizing case-patient interviewing. Conclusion Centers used targeted resources and process evaluation to implement and document practices that improve the completeness and timeliness of FBD surveillance and outbreak response activities

  10. Improvement of the physical properties of ZnO/CdTe core-shell nanowire arrays by CdCl2 heat treatment for solar cells

    PubMed Central

    2014-01-01

    CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells. PMID:24910576

  11. Improvement of the physical properties of ZnO/CdTe core-shell nanowire arrays by CdCl2 heat treatment for solar cells.

    PubMed

    Consonni, Vincent; Renet, Sébastien; Garnier, Jérôme; Gergaud, Patrice; Artús, Lluis; Michallon, Jérôme; Rapenne, Laetitia; Appert, Estelle; Kaminski-Cachopo, Anne

    2014-01-01

    CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells.

  12. Rational Improvement of Molar Absorptivity Guided by Oscillator Strength: A Case Study with Furoindolizine-Based Core Skeleton.

    PubMed

    Lee, Youngjun; Jo, Ala; Park, Seung Bum

    2015-12-21

    The rational improvement of photophysical properties can be highly valuable for the discovery of novel organic fluorophores. Using our new design strategy guided by the oscillator strength, we developed a series of full-color-tunable furoindolizine analogs with improved molar absorptivity through the fusion of a furan ring into the indolizine-based Seoul fluorophore. The excellent correlation between the computable values (oscillator strength and theoretical S0 -S1 energy gap) and photophysical properties (molar absorptivity and emission wavelength) confirmed the effectualness of our design strategy.

  13. Improving communication skill training in patient centered medical practice for enhancing rational use of laboratory tests: The core of bioinformation for leveraging stakeholder engagement in regulatory science.

    PubMed

    Moura, Josemar de Almeida; Costa, Bruna Carvalho; de Faria, Rosa Malena Delbone; Soares, Taciana Figueiredo; Moura, Eliane Perlatto; Chiappelli, Francesco

    2013-01-01

    Requests for laboratory tests are among the most relevant additional tools used by physicians as part of patient's health problemsolving. However, the overestimation of complementary investigation may be linked to less reflective medical practice as a consequence of a poor physician-patient communication, and may impair patient-centered care. This scenario is likely to result from reduced consultation time, and a clinical model focused on the disease. We propose a new medical intervention program that specifically targets improving the patient-centered communication of laboratory tests results, the core of bioinformation in health care. Expectations are that medical students training in communication skills significantly improve physicians-patient relationship, reduce inappropriate use of laboratorial tests, and raise stakeholder engagement.

  14. A Review of the Research: Common Core State Standards for Improving Rural Children's School Readiness

    ERIC Educational Resources Information Center

    Bailey, Lora Battle

    2014-01-01

    Although a plethora of research focuses on economically at-risk preschool children in general across the United States, little can be found that investigates methods for improving rural children's academic outcomes. This review of research is intended to provide a contextual understanding of the background and current conditions that exist…

  15. Trust in Schools: A Core Resource for Improvement. A Volume in the American Sociological Association's Rose Series in Sociology.

    ERIC Educational Resources Information Center

    Bryk, Anthony S.; Schneider, Barbara

    This book uses case studies of 12 Chicago elementary schools undergoing reform (in response to the Chicago School Reform Act of 1988) to examine how effective social relationships can serve as a prime resource for school improvement. It discusses how the myriad social exchanges that make up daily life in a school community generate, or fail to…

  16. Improved estimates of formation factor for combined electrical and nuclear magnetic resonance models of permeability of sandstone cores

    NASA Astrophysics Data System (ADS)

    Osterman, G. K.; Keating, K.; Binley, A. M.; Slater, L. D.; McDonald, R.

    2014-12-01

    In spite of the importance of permeability in controlling numerous hydrogeological and biogeochemical processes, the property can be exceptionally difficult to measure directly in the field. Recently, nuclear magnetic resonance (NMR) has become an increasingly popular method, both in the lab and the field, for hydrogeophysical investigations due to its sensitivity to water content and pore surface area. Additionally, previous work has shown that the electrical formation factor can be used as a proxy for the tortuosity of the pore space—a parameter NMR is incapable of detecting—in permeability models. However, the formation factor is impossible to accurately measure in the field using DC electrical methods, as the measured conductivity cannot be decomposed into the fluid and surface conduction components. Therefore, our approach is to use induced polarization (IP) and spectral induced polarization (SIP) in the laboratory to correct for the influence of surface conductivity in the formation factor calculation. The corrected formation factor can then be used along with NMR parameters for more accurate permeability estimation. Laboratory SIP and NMR datasets were acquired on 40 sandstone cores with a range of permeabilities spanning six orders of magnitude as estimated from gas permeameter measurements. We examine how different estimates of the electrical formation factor can be combined with the NMR transverse relaxation time to estimate permeability. Specifically, we compare the electrical formation factor measured at high and low pore-fluid salinity with the formation factor derived using IP and SIP. Using both empirical and mechanistic petrophysical relationships, we explore the utility of IP- and SIP-corrected formation factors in tandem with NMR parameters for permeability prediction as compared to the low-salinity formation factor typically measured in the field. Furthermore, we develop our models using IP and SIP data that may be acquired in the field

  17. Composite Cores

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Spang & Company's new configuration of converter transformer cores is a composite of gapped and ungapped cores assembled together in concentric relationship. The net effect of the composite design is to combine the protection from saturation offered by the gapped core with the lower magnetizing requirement of the ungapped core. The uncut core functions under normal operating conditions and the cut core takes over during abnormal operation to prevent power surges and their potentially destructive effect on transistors. Principal customers are aerospace and defense manufacturers. Cores also have applicability in commercial products where precise power regulation is required, as in the power supplies for large mainframe computers.

  18. Core-shell nanostructures of covalently grafted polyaniline multi-walled carbon nanotube hybrids for improved optical limiting.

    PubMed

    Remyamol, T; Gopinath, Pramod; John, Honey

    2015-01-01

    Polyaniline multi-walled carbon nanotube (MWCNT) hybrids are synthesized by the in situ polymerization of aniline in the presence of phenylenediamine-functionalized MWCNTs. Along with the aniline monomer, the aniline moiety on the surface of phenylenediamine-functionalized MWCNTs also participates in the polymerization and acts as a covalent bridge between the polyaniline and the MWCNT. The photoluminescence quenching in the hybrid, due to the electron transfer between the polyaniline and the MWCNT, and the resulting improvement in optical limiting are also discussed. The large nonlinear absorption coefficient with the low-limiting threshold of the hybrids compared to polyaniline is attributed to the combined nonlinear optical (NLO) mechanisms and the photo-induced electron transfer interactions.

  19. Improving Photovoltaic Performance of the Linear A-Ar-A-type Small Molecules with Diketopyrropyrrole Arms by Tuning the Linkage Position of the Anthracene Core.

    PubMed

    Duan, Xiongwei; Xiao, Manjun; Chen, Jianhua; Wang, Xiangdong; Peng, Wenhong; Duan, Linrui; Tan, Hua; Lei, Gangtie; Yang, Renqiang; Zhu, Weiguo

    2015-08-26

    Two isomeric A-Ar-A-type small molecules of DPP2An(9,10) and DPP2An(2,6), were synthesized with two acceptor arms of diketopyrropyrroles (DPP) and a planar aryl hydrocarbon core of the different substituted anthracene (An), respectively. Their thermal stability, crystallinity, optoelectronic, and photovoltaic performances were investigated. Significantly red-shifted absorption profile and higher HOMO level were observed for the DPP2An(2,6) with 2,6-substituted anthracene relative to the DPP2An(9,10) with 9,10-substituted anthracene, as the former exhibited better planarity and a larger conjugate system. As a result, the solution-processing solar cells based on DPP2An(2,6) and PC71BM (w/w,1:1) displayed remarkably increased power conversion efficiency of 5.44% and short-circuit current density (Jsc) of 11.90 mA/cm(2) under 1% 1,8-diiodooctane additive. The PCE and Jsc values were 3.7 and 2.9 times those of the optimized DPP2An(9,10)-based cells, respectively. This work demonstrates that changing the linkage position of the anthracene core in the A-Ar-A-type SMs can strongly improve the photovoltaic properties in organic solar cells.

  20. Dual-shell hollow polyaniline/sulfur-core/polyaniline composites improving the capacity and cycle performance of lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    An, Yanling; Wei, Pan; Fan, Meiqiang; Chen, Da; Chen, Haichao; Ju, QiangJian; Tian, Guanglei; Shu, Kangying

    2016-07-01

    In this study, a dual-shell hollow polyaniline/sulfur-core/polyaniline (hPANI/S/PANI) composite was prepared by successively depositing PANI, S, and PANI on the surface of a template silicon sphere. The electrochemical properties of this composite were evaluated using a lithium plate as an anode in lithium/sulfur cells. The hPANI/S/PANI composite showed a discharge capacity of 572.2 mAh g-1 after 214 cycles at 0.1 C, and the Coulombic efficiency was above 87% in the whole charge/discharge cycle. The improved cycle property of the hPANI/S/PANI composite can be ascribed to the fine sulfur particles homogeneously deposited on the PANI surface and sprawled inside the two PANI layers during the charge/discharge cycle. This behavior stabilized the nanostructure of sulfur and enhanced its conductivity.

  1. Tretinoin-loaded lipid-core nanocapsules decrease reactive oxygen species levels and improve bovine embryonic development during in vitro oocyte maturation.

    PubMed

    Lucas, Caroline Gomes; Remião, Mariana Härter; Komninou, Eliza Rossi; Domingues, William Borges; Haas, Cristina; Leon, Priscila Marques Moura de; Campos, Vinicius Farias; Ourique, Aline; Guterres, Silvia S; Pohlmann, Adriana R; Basso, Andrea Cristina; Seixas, Fabiana Kömmling; Beck, Ruy Carlos Ruver; Collares, Tiago

    2015-12-01

    In vitro oocyte maturation (IVM) protocols can be improved by adding chemical supplements to the culture media. Tretinoin is considered an important retinoid in embryonic development and its association with lipid-core nanocapsules (TTN-LNC) represents an innovative way of improving its solubility, and chemical stability, and reducing its toxicity. The effects of supplementing IVM medium with TTN-LNC was evaluated by analyzing production of reactive oxygen species (ROS), S36-phosphorilated-p66Shc levels and caspase activity in early embryonic development, and expression of apoptosis and pluripotency genes in blastocysts. The lowest concentration tested (0.25μM) of TTN-LNC generated higher blastocyst rate, lower ROS production and S36-p66Shc amount. Additionally, expression of BAX and SHC1 were lower in both non-encapsulated tretinoin (TTN) and TTN-LNC-treated groups. Nanoencapsulation allowed the use of smaller concentrations of tretinoin to supplement IVM medium thus reducing toxic effects related with its use, decreasing ROS levels and apoptose frequency, and improving the blastocyst rates.

  2. Enabling Scientific and Technological Improvements to Meet Core Partner Service Requirements in Alaska - An Arctic Test Bed

    NASA Astrophysics Data System (ADS)

    Petrescu, E. M.; Scott, C. A.

    2014-12-01

    NOAA/NWS Test beds, such as the Joint Hurricane Test Bed (Miami, FL) and the Hazardous Weather Test Bed (Norman, OK) have been highly effective in meeting unique or pressing science and service challenges for the NWS. NWS Alaska Region leadership has developed plans for a significant enhancement to our operational forecast and decision support capabilities in Alaska to address the emerging requirements of the Arctic: An Arctic Test Bed. Historically, the complexity of forecast operations and the inherent challenges in Alaska have not been addressed well by the R&D programs and projects that support the CONUS regions of the NWS. In addition, there are unique science,technology, and support challenges (e.g., sea ice forecasts and arctic drilling prospects) and opportunities (Bilateral agreements with Canada, Russia, and Norway) that would best be worked through Alaska operations. A dedicated test bed will provide a mechanism to transfer technology, research results, and observations advances into operations in a timely and effective manner in support of Weather Ready Nation goals and to enhance decision support services in Alaska. A NOAA Arctic Test Bed will provide a crucial nexus for ensuring NOAA's developers understand Alaska's needs, which are often cross disciplinary (atmosphere, ocean, cryosphere, and hydrologic), to improve NOAA's responsiveness to its Arctic-related science and service priorities among the NWS and OAR (CPO and ESRL), and enable better leveraging of other research initiatives and data sources external to NOAA, including academia, other government agencies, and the private sector, which are particular to the polar region (e.g., WWRP Polar Prediction Project). Organization, capabilities and opportunities will be presentation.

  3. Determination of lead isotopes in a new Greenland deep ice core at the sub-picogram per gram level by thermal ionization mass spectrometry using an improved decontamination method.

    PubMed

    Han, Changhee; Burn-Nunes, Laurie J; Lee, Khanghyun; Chang, Chaewon; Kang, Jung-Ho; Han, Yeongcheol; Hur, Soon Do; Hong, Sungmin

    2015-08-01

    An improved decontamination method and ultraclean analytical procedures have been developed to minimize Pb contamination of processed glacial ice cores and to achieve reliable determination of Pb isotopes in North Greenland Eemian Ice Drilling (NEEM) deep ice core sections with concentrations at the sub-picogram per gram level. A PL-7 (Fuso Chemical) silica-gel activator has replaced the previously used colloidal silica activator produced by Merck and has been shown to provide sufficiently enhanced ion beam intensity for Pb isotope analysis for a few tens of picograms of Pb. Considering the quantities of Pb contained in the NEEM Greenland ice core and a sample weight of 10 g used for the analysis, the blank contribution from the sample treatment was observed to be negligible. The decontamination and analysis of the artificial ice cores and selected NEEM Greenland ice core sections confirmed the cleanliness and effectiveness of the overall analytical process.

  4. Advanced Burner Reactor with Breed-and-Burn Thorium Blankets for Improved Economics and Resource Utilization

    SciTech Connect

    Greenspan, Ehud

    2015-11-04

    This study assesses the feasibility of designing Seed and Blanket (S&B) Sodium-cooled Fast Reactor (SFR) to generate a significant fraction of the core power from radial thorium fueled blankets that operate on the Breed-and-Burn (B&B) mode without exceeding the radiation damage constraint of presently verified cladding materials. The S&B core is designed to maximize the fraction of neutrons that radially leak from the seed (or “driver”) into the subcritical blanket and reduce neutron loss via axial leakage. The blanket in the S&B core makes beneficial use of the leaking neutrons for improved economics and resource utilization. A specific objective of this study is to maximize the fraction of core power that can be generated by the blanket without violating the thermal hydraulic and material constraints. Since the blanket fuel requires no reprocessing along with remote fuel fabrication, a larger fraction of power from the blanket will result in a smaller fuel recycling capacity and lower fuel cycle cost per unit of electricity generated. A unique synergism is found between a low conversion ratio (CR) seed and a B&B blanket fueled by thorium. Among several benefits, this synergism enables the very low leakage S&B cores to have small positive coolant voiding reactivity coefficient and large enough negative Doppler coefficient even when using inert matrix fuel for the seed. The benefits of this synergism are maximized when using an annular seed surrounded by an inner and outer thorium blankets. Among the high-performance S&B cores designed to benefit from this unique synergism are: (1) the ultra-long cycle core that features a cycle length of ~7 years; (2) the high-transmutation rate core where the seed fuel features a TRU CR of 0.0. Its TRU transmutation rate is comparable to that of the reference Advanced Burner Reactor (ABR) with CR of 0.5 and the thorium blanket can generate close to 60% of the core power; but requires only one sixth of the reprocessing and

  5. Toward the Cenozoic Megasplice - high-resolution XRF core scanning data and improved composite records from IODP Expedition 320: implications for fine scale paleoceanography (Invited)

    NASA Astrophysics Data System (ADS)

    Westerhold, T.; Bown, P. R.; Dunkley Jones, T.; Lyle, M. W.; Moore, T. C.; Pälike, H.; Roehl, U.; Wilkens, R. H.; Expedition 320/321 Scientists

    2010-12-01

    A critical need to study past climate change is to sufficiently constrain the ages of past climate events so that global relationships can be discerned. Integrated Ocean Drilling Program (IODP) Expedition 320 recovered high-quality pelagic Cenozoic records with over 800 dated paleomagnetic reversals and decimeter-scale cyclic sediments. These new profiles provide an outstanding framework to inter-calibrate major microfossil groups and refine magnetic polarity chrons for the late Miocene, the entire Oligocene and the late Eocene Epochs. The compilation of a Cenozoic Megasplice which integrates all available bio-, chemo-, and magnetostratigraphic data including those from key records already recovered during Ocean Drilling Program (ODP) Leg 199 is one of the major objectives of the Pacific Equatorial Age Transect (PEAT, IODP Exp. 320 & 321) and prerequisite for further reconstructing the climate history of the Equatorial Pacific in detail. Here we present extended post-cruise refinements of the shipboard composite records of IODP Exp. 320 Sites U1331, U1332, U1333, U1334 as well as ODP Leg 199 Sites 1218, 1219 and 1220. The revised composite records were used to perform a site-to-site correlation and integration of Leg 199 and Exp. 320 sites. Based on this decimeter scale correlation a high resolution integrated paleomagnetic and biostratigraphic framework for the Equatorial Pacific is established which covers the time interval from 20 to 40 Ma. This framework will be the key for further high-resolution paleoceanographic interpretations of the late Paleogene, e.g. the E/O transition. As part of our study we also present high resolution X-ray fluorescence (XRF) core scanning data acquired from more than 1200 meters of sediment cores from Exp. 320 and Leg 199 encompassing the middle Eocene to early Oligocene (magnetochrons C12n to C20n). These new, critical records enable us to improve the orbitally tuned time scale and to reconstruct variations in the carbonate

  6. The role of galaxy interaction in the SFR-M {sub *} relation: characterizing morphological properties of Herschel-selected galaxies at 0.2 < z < 1.5

    SciTech Connect

    Hung, Chao-Ling; Sanders, D. B.; Casey, C. M.; Lee, N.; Barnes, J. E.; Koss, M.; Larson, K. L.; Lockhart, K.; Man, A. W. S.; Mann, A. W.; Capak, P.; Kartaltepe, J. S.; Le Floc'h, E.; Riguccini, L.; Scoville, N.; Symeonidis, M.

    2013-12-01

    Galaxy interactions/mergers have been shown to dominate the population of IR-luminous galaxies (L {sub IR} ≳ 10{sup 11.6} L {sub ☉}) in the local universe (z ≲ 0.25). Recent studies based on the relation between galaxies' star formation rates and stellar mass (the SFR-M {sub *} relation or the {sup g}alaxy main sequence{sup )} have suggested that galaxy interaction/mergers may only become significant when galaxies fall well above the galaxy main sequence. Since the typical SFR at a given M {sub *} increases with redshift, the existence of the galaxy main sequence implies that massive, IR-luminous galaxies at high z may not necessarily be driven by galaxy interactions. We examine the role of galaxy interactions in the SFR-M {sub *} relation by carrying out a morphological analysis of 2084 Herschel-selected galaxies at 0.2 < z < 1.5 in the COSMOS field. Using a detailed visual classification scheme, we show that the fraction of 'disk galaxies' decreases and the fraction of 'irregular' galaxies increases systematically with increasing L {sub IR} out to z ≲ 1.5 and z ≲ 1.0, respectively. At L {sub IR} >10{sup 11.5} L {sub ☉}, ≳ 50% of the objects show evident features of strongly interacting/merger systems, where this percentage is similar to the studies of local IR-luminous galaxies. The fraction of interacting/merger systems also systematically increases with the deviation from the SFR-M {sub *} relation, supporting the view that galaxies falling above the main sequence are more dominated by mergers than the main-sequence galaxies. Meanwhile, we find that ≳ 18% of massive IR-luminous 'main-sequence galaxies' are classified as interacting systems, where this population may not evolve through the evolutionary track predicted by a simple gas exhaustion model.

  7. Assessment of SFR fuel pin performance codes under advanced fuel for minor actinide transmutation

    SciTech Connect

    Bouineau, V.; Lainet, M.; Chauvin, N.; Pelletier, M.

    2013-07-01

    Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors of long-lived nuclides like {sup 241}Am is, therefore, an option for the reduction of radiotoxicity and residual power packages as well as the repository area. In the SUPERFACT Experiment four different oxide fuels containing high and low concentrations of {sup 237}Np and {sup 241}Am, representing the homogeneous and heterogeneous in-pile recycling concepts, were irradiated in the PHENIX reactor. The behavior of advanced fuel materials with minor actinide needs to be fully characterized, understood and modeled in order to optimize the design of this kind of fuel elements and to evaluate its performances. This paper assesses the current predictability of fuel performance codes TRANSURANUS and GERMINAL V2 on the basis of post irradiation examinations of the SUPERFACT experiment for pins with low minor actinide content. Their predictions have been compared to measured data in terms of geometrical changes of fuel and cladding, fission gases behavior and actinide and fission product distributions. The results are in good agreement with the experimental results, although improvements are also pointed out for further studies, especially if larger content of minor actinide will be taken into account in the codes. (authors)

  8. Lunar Core and Tides

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.

    2004-01-01

    Variations in rotation and orientation of the Moon are sensitive to solid-body tidal dissipation, dissipation due to relative motion at the fluid-core/solid-mantle boundary, and tidal Love number k2 [1,2]. There is weaker sensitivity to flattening of the core-mantle boundary (CMB) [2,3,4] and fluid core moment of inertia [1]. Accurate Lunar Laser Ranging (LLR) measurements of the distance from observatories on the Earth to four retroreflector arrays on the Moon are sensitive to lunar rotation and orientation variations and tidal displacements. Past solutions using the LLR data have given results for dissipation due to solid-body tides and fluid core [1] plus Love number [1-5]. Detection of CMB flattening, which in the past has been marginal but improving [3,4,5], now seems significant. Direct detection of the core moment has not yet been achieved.

  9. Improvements in tissue blood flow and lumbopelvic stability after lumbopelvic core stabilization training in patients with chronic non-specific low back pain.

    PubMed

    Paungmali, Aatit; Henry, Leonard Joseph; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn

    2016-01-01

    [Purpose] This study investigated the effects of lumbopelvic stabilization training on tissue blood flow changes in the lumbopelvic region and lumbopelvic stability compared to placebo treatment and controlled intervention among patients with chronic non-specific low back pain. [Subjects and Methods] A total of 25 participants (7 males, 18 females; mean age, 33.3 ± 14.4 years) participated in this within-subject, repeated-measures, double-blind, placebo-controlled comparison trial. The participants randomly underwent three types of interventions that included lumbopelvic stabilization training, placebo treatment, and controlled intervention with 48 hours between sessions. Lumbopelvic stability and tissue blood flow were measured using a pressure biofeedback device and a laser Doppler flow meter before and after the interventions. [Results] The repeated-measures analysis of variance results demonstrated a significant increase in tissue blood flow over the lumbopelvic region tissues for post- versus pre-lumbopelvic stabilization training and compared to placebo and control interventions. A significant increase in lumbopelvic stability before and after lumbopelvic stabilization training was noted, as well as upon comparison to placebo and control interventions. [Conclusion] The current study supports an increase in tissue blood flow in the lumbopelvic region and improved lumbopelvic stability after core training among patients with chronic non-specific low back pain.

  10. Improvements in tissue blood flow and lumbopelvic stability after lumbopelvic core stabilization training in patients with chronic non-specific low back pain.

    PubMed

    Paungmali, Aatit; Henry, Leonard Joseph; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn

    2016-01-01

    [Purpose] This study investigated the effects of lumbopelvic stabilization training on tissue blood flow changes in the lumbopelvic region and lumbopelvic stability compared to placebo treatment and controlled intervention among patients with chronic non-specific low back pain. [Subjects and Methods] A total of 25 participants (7 males, 18 females; mean age, 33.3 ± 14.4 years) participated in this within-subject, repeated-measures, double-blind, placebo-controlled comparison trial. The participants randomly underwent three types of interventions that included lumbopelvic stabilization training, placebo treatment, and controlled intervention with 48 hours between sessions. Lumbopelvic stability and tissue blood flow were measured using a pressure biofeedback device and a laser Doppler flow meter before and after the interventions. [Results] The repeated-measures analysis of variance results demonstrated a significant increase in tissue blood flow over the lumbopelvic region tissues for post- versus pre-lumbopelvic stabilization training and compared to placebo and control interventions. A significant increase in lumbopelvic stability before and after lumbopelvic stabilization training was noted, as well as upon comparison to placebo and control interventions. [Conclusion] The current study supports an increase in tissue blood flow in the lumbopelvic region and improved lumbopelvic stability after core training among patients with chronic non-specific low back pain. PMID:27064327

  11. High-capacity carbon-coated titanium dioxide core-shell nanoparticles modified three dimensional anodes for improved energy output in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Tang, Jiahuan; Yuan, Yong; Liu, Ting; Zhou, Shungui

    2015-01-01

    Three-dimensional (3D) electrodes have been intensively investigated as alternatives to conventional plate electrodes in the development of high-performance microbial fuel cells (MFCs). However, the energy output of the MFCs with the 3D anodes is still limited for practical applications. In this study, a 3D anode modified with a nano-structured capacitive layer is prepared to improve the performance of an microbial fuel cell (MFC). The capacitive layer composes of titanium dioxide (TiO2) and egg white protein (EWP)-derived carbon assembled core-shell nanoparticles, which are integrated into loofah sponge carbon (LSC) to obtain a high-capacitive 3D electrode. The as-prepared 3D anode produces a power density of 2.59 ± 0.12 W m-2, which is 63% and 201% higher than that of the original LSC and graphite anodes, respectively. The increased energy output is contributed to the enhanced electrochemical capacitance of the 3D anodes as well as the synergetic effects between TiO2 and EWP-derived carbon due to their unique properties, such as relatively high surface area, good biocompatibility, and favorable surface functionalization for interfacial microbial electron transfer. The results obtained in this study will benefit the optimized design of new 3D materials to achieve enhanced performance in MFCs.

  12. Improvements in tissue blood flow and lumbopelvic stability after lumbopelvic core stabilization training in patients with chronic non-specific low back pain

    PubMed Central

    Paungmali, Aatit; Henry, Leonard Joseph; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn

    2016-01-01

    [Purpose] This study investigated the effects of lumbopelvic stabilization training on tissue blood flow changes in the lumbopelvic region and lumbopelvic stability compared to placebo treatment and controlled intervention among patients with chronic non-specific low back pain. [Subjects and Methods] A total of 25 participants (7 males, 18 females; mean age, 33.3 ± 14.4 years) participated in this within-subject, repeated-measures, double-blind, placebo-controlled comparison trial. The participants randomly underwent three types of interventions that included lumbopelvic stabilization training, placebo treatment, and controlled intervention with 48 hours between sessions. Lumbopelvic stability and tissue blood flow were measured using a pressure biofeedback device and a laser Doppler flow meter before and after the interventions. [Results] The repeated-measures analysis of variance results demonstrated a significant increase in tissue blood flow over the lumbopelvic region tissues for post- versus pre-lumbopelvic stabilization training and compared to placebo and control interventions. A significant increase in lumbopelvic stability before and after lumbopelvic stabilization training was noted, as well as upon comparison to placebo and control interventions. [Conclusion] The current study supports an increase in tissue blood flow in the lumbopelvic region and improved lumbopelvic stability after core training among patients with chronic non-specific low back pain. PMID:27064327

  13. Global Core Plasma Model

    NASA Technical Reports Server (NTRS)

    Gallagher, Dennis L.; Craven, P. D.; Comfort, R. H.

    1999-01-01

    Abstract. The Global Core Plasma Model (GCPM) provides, empirically derived, core plasma density as a function of geomagnetic and solar conditions throughout the inner magnetosphere. It is continuous in value and gradient and is composed of separate models for the ionosphere, the plasmasphere, the plasmapause, the trough, and the polar cap. The relative composition of plasmaspheric H+, He+, and O+ is included in the GCPM. A blunt plasmaspheric bulge and rotation of the bulge with changing geomagnetic conditions is included. The GCPM is an amalgam of density models, intended to serve as a framework for continued improvement as new measurements become available and are used to characterize core plasma density, composition, and temperature.

  14. Blood Pressure Control Has Improved in People with and without Type 2 Diabetes but Remains Suboptimal: A Longitudinal Study Based on the German DIAB-CORE Consortium

    PubMed Central

    Rückert, Ina-Maria; Baumert, Jens; Schunk, Michaela; Holle, Rolf; Schipf, Sabine; Völzke, Henry; Kluttig, Alexander; Greiser, Karin-Halina; Tamayo, Teresa; Rathmann, Wolfgang; Meisinger, Christa

    2015-01-01

    Background Hypertension is a very common comorbidity and major risk factor for cardiovascular complications, especially in people with Type 2 Diabetes (T2D). Nevertheless, studies in the past have shown that blood pressure is often insufficiently controlled in medical practice. For the DIAB-CARE study, we used longitudinal data based on the German DIAB-CORE Consortium to assess whether health care regarding hypertension has improved during the last decade in our participants. Methods Data of the three regional population-based studies CARLA (baseline 2002-2006 and follow-up 2007-2010), KORA (baseline 1999-2001 and follow-up 2006-2008) and SHIP (baseline 1997-2001 and follow-up 2002-2006) were pooled. Stratified by T2D status we analysed changes in frequencies, degrees of awareness, treatment and control. Linear mixed models were conducted to assess the influence of sex, age, study, and T2D status on changes of systolic blood pressure between the baseline and follow-up examinations (mean observation time 5.7 years). We included 4,683 participants aged 45 to 74 years with complete data and accounted for 1,256 participants who were lost to follow-up by inverse probability weighting. Results Mean systolic blood pressure decreased in all groups from baseline to follow-up (e.g. – 8.5 mmHg in those with incident T2D). Pulse pressure (PP) was markedly higher in persons with T2D than in persons without T2D (64.14 mmHg in prevalent T2D compared to 52.87 mmHg in non-T2D at baseline) and did not change much between the two examinations. Awareness, treatment and control increased considerably in all subgroups however, the percentage of those with insufficiently controlled hypertension remained high (at about 50% of those with hypertension) especially in prevalent T2D. Particularly elderly people with T2D often had both, high blood pressure ≥140/90 mmHg and a PP of ≥60 mmHg. Blood pressure in men had improved more than in women at follow-up, however, men still had higher

  15. Using in-situ observations of atmospheric water vapor isotopes to benchmark and isotope-enabled General Circulation Models and improve ice core paleo-climate reconstruction

    NASA Astrophysics Data System (ADS)

    Steen-Larsen, Hans Christian; Sveinbjörnsdottir, Arny; Masson-Delmotte, Valerie; Werner, Martin; Risi, Camille; Yoshimura, Kei

    2016-04-01

    We have since 2010 carried out in-situ continuous water vapor isotope observations on top of the Greenland Ice Sheet (3 seasons at NEEM), in Svalbard (1 year), in Iceland (4 years), in Bermuda (4 years). The expansive dataset containing high accuracy and precision measurements of δ18O, δD, and the d-excess allow us to validate and benchmark the treatment of the atmospheric hydrological cycle's processes in General Circulation Models using simulations nudged to reanalysis products. Recent findings from both Antarctica and Greenland have documented strong interaction between the snow surface isotopes and the near surface atmospheric water vapor isotopes on diurnal to synoptic time scales. In fact, it has been shown that the snow surface isotopes take up the synoptic driven atmospheric water vapor isotopic signal in-between precipitation events, erasing the precipitation isotope signal in the surface snow. This highlights the importance of using General or Regional Climate Models, which accurately are able to simulate the atmospheric water vapor isotopic composition, to understand and interpret the ice core isotope signal. With this in mind we have used three isotope-enabled General Circulation Models (isoGSM, ECHAM5-wiso, and LMDZiso) nudged to reanalysis products. We have compared the simulations of daily mean isotope values directly with our in-situ observations. This has allowed us to characterize the variability of the isotopic composition in the models and compared it to our observations. We have specifically focused on the d-excess in order to characterize why both the mean and the variability is significantly lower than our observations. We argue that using water vapor isotopes to benchmark General Circulation Models offers an excellent tool for improving the treatment and parameterization of the atmospheric hydrological cycle. Recent studies have documented a very large inter-model dispersion in the treatment of the Arctic water cycle under a future global

  16. Using in-situ observations of atmospheric water vapor isotopes to benchmark and isotope-enabled General Circulation Models and improve ice core paleo-climate reconstruction

    NASA Astrophysics Data System (ADS)

    Steen-Larsen, H. C.; Sveinbjörnsdottir, A. E.; Peters, A.; Werner, M.; Risi, C. M.; Yoshimura, K.; Masson-Delmotte, V.

    2015-12-01

    We have since 2010 carried out in-situ continuous water vapor isotope observations on top of the Greenland Ice Sheet (3 seasons at NEEM), in Svalbard (1 year), in Iceland (4 years), in Bermuda (4 years). The expansive dataset containing high accuracy and precision measurements of δ18O, δD, and the d-excess allow us to validate and benchmark the treatment of the atmospheric hydrological cycle's processes in General Circulation Models using simulations nudged to reanalysis products. Recent findings from both Antarctica and Greenland have documented strong interaction between the snow surface isotopes and the near surface atmospheric water vapor isotopes on diurnal to synoptic time scales. In fact, it has been shown that the snow surface isotopes take up the synoptic driven atmospheric water vapor isotopic signal in-between precipitation events, erasing the precipitation isotope signal in the surface snow. This highlights the importance of using General or Regional Climate Models, which accurately are able to simulate the atmospheric water vapor isotopic composition, to understand and interpret the ice core isotope signal. With this in mind we have used three isotope-enabled General Circulation Models (isoGSM, ECHAM5-wiso, and LMDZiso) nudged to reanalysis products. We have compared the simulations of daily mean isotope values directly with our in-situ observations. This has allowed us to characterize the variability of the isotopic composition in the models and compared it to our observations. We have specifically focused on the d-excess in order to characterize why both the mean and the variability is significantly lower than our observations. We argue that using water vapor isotopes to benchmark General Circulation Models offers an excellent tool for improving the treatment and parameterization of the atmospheric hydrological cycle. Recent studies have documented a very large inter-model dispersion in the treatment of the Arctic water cycle under a future global

  17. 24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES FOR A BRASS GATE VALVE BODY MADE ON A CORE BOX, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  18. The Replacement of 10 Non-Conserved Residues in the Core Protein of JFH-1 Hepatitis C Virus Improves Its Assembly and Secretion

    PubMed Central

    Etienne, Loïc; Blanchard, Emmanuelle; Boyer, Audrey; Desvignes, Virginie; Gaillard, Julien; Meunier, Jean-Christophe; Roingeard, Philippe; Hourioux, Christophe

    2015-01-01

    Hepatitis C virus (HCV) assembly is still poorly understood. It is thought that trafficking of the HCV core protein to the lipid droplet (LD) surface is essential for its multimerization and association with newly synthesized HCV RNA to form the viral nucleocapsid. We carried out a mapping analysis of several complete HCV genomes of all genotypes, and found that the genotype 2 JFH-1 core protein contained 10 residues different from those of other genotypes. The replacement of these 10 residues of the JFH-1 strain sequence with the most conserved residues deduced from sequence alignments greatly increased virus production. Confocal microscopy of the modified JFH-1 strain in cell culture showed that the mutated JFH-1 core protein, C10M, was present mostly at the endoplasmic reticulum (ER) membrane, but not at the surface of the LDs, even though its trafficking to these organelles was possible. The non-structural 5A protein of HCV was also redirected to ER membranes and colocalized with the C10M core protein. Using a Semliki forest virus vector to overproduce core protein, we demonstrated that the C10M core protein was able to form HCV-like particles, unlike the native JFH-1 core protein. Thus, the substitution of a few selected residues in the JFH-1 core protein modified the subcellular distribution and assembly properties of the protein. These findings suggest that the early steps of HCV assembly occur at the ER membrane rather than at the LD surface. The C10M-JFH-1 strain will be a valuable tool for further studies of HCV morphogenesis. PMID:26339783

  19. An upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticle photoelectrode for improved efficiencies of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Shen, Haiou; Guo, Wei; Wang, Shunhao; Zhu, Chuntao; Xue, Fang; Hou, Jinfeng; Su, Haiquan; Yuan, Zhuobin

    2013-03-01

    Novel upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticles (NPs) are synthesized and used to prepare the photoelectrode (PE) of dye-sensitized solar cells (DSSCs). The morphology, structure, photoluminescence characterization of the NaYF4:Yb3+,Er3+/TiO2 core-shell NPs and the photoelectric performance, alternating current impedance spectroscopy of DSSCs are characterized using transmission electron microscopy, X-ray diffraction, upconversion luminescence (UCL) spectrofluorimetry and electrochemistry. Compared with the pure TiO2 PE or the NaYF4:Yb3+,Er3+ upconversion NPs and TiO2 simply mixed prepared PE as the volume ratio of the core-shell structure, the DSSCs with the upconversion core-shell PE show a greater photovoltaic efficiency. The energy conversion efficiency of the DSSCs with a NaYF4:Yb3+,Er3+/TiO2 PE is 23.1% higher than with a pure TiO2 PE and 99.1% higher than with a mixed PE using the same conditions. This enhancement is due to the UCL core extending the spectral response range of DSSCs to the infrared region and their particular shell structure, retaining its semiconductor character. This method represents a novel approach to increase the efficiencies of DSSCs.

  20. Evaluation of the effect of B and N on the microstructure of 9Cr-2W steel during an aging treatment for SFR fuel cladding tubes

    NASA Astrophysics Data System (ADS)

    Jeong, Eun Hee; Park, Sang-Gyu; Kim, Sung Ho; Kim, Young Do

    2015-12-01

    In this study, the microstructure of sodium-cooled fast reactor (SFR) fuel cladding steel with different B and N contents after aging is compared. The addition of nitrogen produces a large quantity of MX precipitates with sizes of 0.1 μm or smaller during the initial thermal treatment process and this contributes to help such precipitates maintain stability without being excessively affected by aging. B is primarily distributed in the grain boundary precipitates and grain interior precipitates in the initial stage. The B distribution is believed to move to the Cr precipitates after 7000 h and to contribute to suppressing the growth of M23C6.

  1. Core-Noise Research

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2012-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system-level noise metrics for the 2015 (N+1), 2020 (N+2), and 2025 (N+3) timeframes; SFW strategic thrusts and technical challenges; SFW advanced subsystems that are broadly applicable to N+3 vehicle concepts, with an indication where further noise research is needed; the components of core noise (compressor, combustor and turbine noise) and a rationale for NASA's current emphasis on the combustor-noise component; the increase in the relative importance of core noise due to turbofan design trends; the need to understand and mitigate core-noise sources for high-efficiency small gas generators; and the current research activities in the core-noise area, with additional details given about forthcoming updates to NASA's Aircraft Noise Prediction Program (ANOPP) core-noise prediction capabilities, two NRA efforts (Honeywell International, Phoenix, AZ and University of Illinois at Urbana-Champaign, respectively) to improve the understanding of core-noise sources and noise propagation through the engine core, and an effort to develop oxide/oxide ceramic-matrix-composite (CMC) liners for broadband noise attenuation suitable for turbofan-core application. Core noise must be addressed to ensure that the N+3 noise goals are met. Focused, but long-term, core-noise research is carried out to enable the advanced high-efficiency small gas-generator subsystem, common to several N+3 conceptual designs, needed to meet NASA's technical challenges. Intermediate updates to prediction tools are implemented as the understanding of the source structure and engine-internal propagation effects is improved. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The

  2. Core layering

    NASA Astrophysics Data System (ADS)

    Jacobson, S. A.; Rubie, D. C.; Hernlund, J. W.; Morbidelli, A.

    2015-12-01

    We have created a planetary accretion and differentiation model that self-consistently builds and evolves Earth's core. From this model, we show that the core grows stably stratified as the result of rising metal-silicate equilibration temperatures and pressures, which increases the concentrations of light element impurities into each newer core addition. This stable stratification would naturally resist convection and frustrate the onset of a geodynamo, however, late giant impacts could mechanically mix the distinct accreted core layers creating large homogenous regions. Within these regions, a geodynamo may operate. From this model, we interpret the difference between the planetary magnetic fields of Earth and Venus as a difference in giant impact histories. Our planetary accretion model is a numerical N-body integration of the Grand Tack scenario [1]—the most successful terrestrial planet formation model to date [2,3]. Then, we take the accretion histories of Earth-like and Venus-like planets from this model and post-process the growth of each terrestrial planet according to a well-tested planetary differentiation model [4,5]. This model fits Earth's mantle by modifying the oxygen content of the pre-cursor planetesimals and embryos as well as the conditions of metal-silicate equilibration. Other non-volatile major, minor and trace elements included in the model are assumed to be in CI chondrite proportions. The results from this model across many simulated terrestrial planet growth histories are robust. If the kinetic energy delivered by larger impacts is neglected, the core of each planet grows with a strong stable stratification that would significantly impede convection. However, if giant impact mixing is very efficient or if the impact history delivers large impacts late, than the stable stratification can be removed. [1] Walsh et al. Nature 475 (2011) [2] O'Brien et al. Icarus 223 (2014) [3] Jacobson & Morbidelli PTRSA 372 (2014) [4] Rubie et al. EPSL 301

  3. A novel structural Fenton-like nanocatalyst with highly improved catalytic performance for generalized preparation of iron oxide@organic dye polymer core-shell nanospheres.

    PubMed

    Zhao, Guanghui; Peng, Xiaomen; Li, Hongping; Wang, Jianzhi; Zhou, Lincheng; Zhao, Tianqi; Huang, Zhihao; Jiang, Haifei

    2015-05-01

    FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core-shell nanospheres.

  4. Understanding and improving flavor in beans: Screening the USDA Phaseolus core collection for pod sugar and flavor compounds in snap and dry bean accessions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of our research is to gain knowledge regarding variation in sugar and flavor content among a sample of dry bean and green pod-type accessions from the USDA Phaseolus Germplasm Core Collection, Pullman, WA. Knowledge of the variation will allow better utilization of germplasm resources ...

  5. Standards-Based Multiple Measures for IASA, Title I Program Improvement Accountability: A Vital Link with District Core Values. Rowland Unified School District.

    ERIC Educational Resources Information Center

    Kolls, Mardel R.

    In 1995 the Rowland Unified School District (California) developed a new mission statement defining core values for the district's preparation for the 21st century. The district then set about implementing a new accountability system with existing measures to establish baseline data for measuring progress toward the new goals. The focus in this…

  6. A novel structural Fenton-like nanocatalyst with highly improved catalytic performance for generalized preparation of iron oxide@organic dye polymer core-shell nanospheres.

    PubMed

    Zhao, Guanghui; Peng, Xiaomen; Li, Hongping; Wang, Jianzhi; Zhou, Lincheng; Zhao, Tianqi; Huang, Zhihao; Jiang, Haifei

    2015-05-01

    FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core-shell nanospheres. PMID:25828271

  7. Validation of updated neutronic calculation models proposed for Atucha-II PHWR. Part II: Benchmark comparisons of PUMA core parameters with MCNP5 and improvements due to a simple cell heterogeneity correction

    SciTech Connect

    Grant, C.; Mollerach, R.; Leszczynski, F.; Serra, O.; Marconi, J.; Fink, J.

    2006-07-01

    In 2005 the Argentine Government took the decision to complete the construction of the Atucha-II nuclear power plant, which has been progressing slowly during the last ten years. Atucha-II is a 745 MWe nuclear station moderated and cooled with heavy water, of German (Siemens) design located in Argentina. It has a pressure vessel design with 451 vertical coolant channels and the fuel assemblies (FA) are clusters of 37 natural UO{sub 2} rods with an active length of 530 cm. For the reactor physics area, a revision and update of reactor physics calculation methods and models was recently carried out covering cell, supercell (control rod) and core calculations. This paper presents benchmark comparisons of core parameters of a slightly idealized model of the Atucha-I core obtained with the PUMA reactor code with MCNP5. The Atucha-I core was selected because it is smaller, similar from a neutronic point of view, more symmetric than Atucha-II, and has some experimental data available. To validate the new models benchmark comparisons of k-effective, channel power and axial power distributions obtained with PUMA and MCNP5 have been performed. In addition, a simple cell heterogeneity correction recently introduced in PUMA is presented, which improves significantly the agreement of calculated channel powers with MCNP5. To complete the validation, the calculation of some of the critical configurations of the Atucha-I reactor measured during the experiments performed at first criticality is also presented. (authors)

  8. Core-Noise

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2010-01-01

    This presentation is a technical progress report and near-term outlook for NASA-internal and NASA-sponsored external work on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system level noise metrics for the 2015, 2020, and 2025 timeframes; the emerging importance of core noise and its relevance to the SFW Reduced-Noise-Aircraft Technical Challenge; the current research activities in the core-noise area, with some additional details given about the development of a high-fidelity combustion-noise prediction capability; the need for a core-noise diagnostic capability to generate benchmark data for validation of both high-fidelity work and improved models, as well as testing of future noise-reduction technologies; relevant existing core-noise tests using real engines and auxiliary power units; and examples of possible scenarios for a future diagnostic facility. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The SFW Reduced-Noise-Aircraft Technical Challenge aims to enable concepts and technologies to dramatically reduce the perceived aircraft noise outside of airport boundaries. This reduction of aircraft noise is critical for enabling the anticipated large increase in future air traffic. Noise generated in the jet engine core, by sources such as the compressor, combustor, and turbine, can be a significant contribution to the overall noise signature at low-power conditions, typical of approach flight. At high engine power during takeoff, jet and fan noise have traditionally dominated over core noise. However, current design trends and expected technological advances in engine-cycle design as well as noise-reduction methods are likely to reduce non-core noise even at engine-power points higher than approach. In addition, future low-emission combustor designs could increase

  9. NUCLEAR REACTOR CORE DESIGN

    DOEpatents

    Mahlmeister, J.E.; Peck, W.S.; Haberer, W.V.; Williams, A.C.

    1960-03-22

    An improved core design for a sodium-cooled, graphitemoderated nuclear reactor is described. The improved reactor core comprises a number of blocks of moderator material, each block being in the shape of a regular prism. A number of channels, extending the length of each block, are disposed around the periphery. When several blocks are placed in contact to form the reactor core, the channels in adjacent blocks correspond with each other to form closed conduits extending the length of the core. Fuel element clusters are disposed in these closed conduits, and liquid coolant is forced through the annulus between the fuel cluster and the inner surface of the conduit. In a preferred embodiment of the invention, the moderator blocks are in the form of hexagonal prisms with longitudinal channels cut into the corners of the hexagon. The main advantage of an "edge-loaded" moderator block is that fewer thermal neutrons are absorbed by the moderator cladding, as compared with a conventional centrally loaded moderator block.

  10. Core Noise - Increasing Importance

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2011-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system-level noise metrics for the 2015, 2020, and 2025 timeframes; turbofan design trends and their aeroacoustic implications; the emerging importance of core noise and its relevance to the SFW Reduced-Perceived-Noise Technical Challenge; and the current research activities in the core-noise area, with additional details given about the development of a high-fidelity combustor-noise prediction capability as well as activities supporting the development of improved reduced-order, physics-based models for combustor-noise prediction. The need for benchmark data for validation of high-fidelity and modeling work and the value of a potential future diagnostic facility for testing of core-noise-reduction concepts are indicated. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The SFW Reduced-Perceived-Noise Technical Challenge aims to develop concepts and technologies to dramatically reduce the perceived aircraft noise outside of airport boundaries. This reduction of aircraft noise is critical to enabling the anticipated large increase in future air traffic. Noise generated in the jet engine core, by sources such as the compressor, combustor, and turbine, can be a significant contribution to the overall noise signature at low-power conditions, typical of approach flight. At high engine power during takeoff, jet and fan noise have traditionally dominated over core noise. However, current design trends and expected technological advances in engine-cycle design as well as noise-reduction methods are likely to reduce non-core noise even at engine-power points higher than approach. In addition, future low-emission combustor

  11. Tailor-made polyfluoroacrylate and its block copolymer by RAFT polymerization in miniemulsion; improved hydrophobicity in the core-shell block copolymer.

    PubMed

    Chakrabarty, Arindam; Singha, Nikhil K

    2013-10-15

    Controlled/living radical polymerization (CRP) of a fluoroacrylate was successfully carried out in miniemulsion by Reversible Addition Fragmentation chain Transfer (RAFT) process. In this case, 2,2,3,3,4,4,4-heptafluorobutyl acrylate (HFBA) was polymerized using 2-cyanopropyl dodecyl trithiocarbonate (CPDTC) as RAFT agent, Triton X-405 and sodium dodecyl sulfonate (SDS) as surfactant, and potassium persulphate (KPS) or 2,2'-azobis isobutyronitrile (AIBN) as initiator. Being compatible with hydrophobic fluoroacrylate, this RAFT agent offered very high conversion and good control over the molecular weight of the polymer. The miniemulsion was stable without any costabilizer. The long chain dodecyl group (-C12H25) (Z-group in the RAFT agent) had beneficial effect in stabilizing the miniemulsion. When 2-cyano 2-propyl benzodithioate (CPBD) (Z=-C6H5) was used as RAFT agent, the conversion was less and particle size distribution was very broad. Block copolymerization with butyl acrylate (BA) using PHFBA as macro-RAFT agent showed core-shell morphology with the aggregation of PHFBA segment in the shell. GPC as well as DSC analysis confirmed the formation of block copolymer. The core-shell morphology was confirmed by TEM analysis. The block copolymers (PHFBA-b-PBA) showed significantly higher water contact angle (WCA) showing much better hydrophobicity compared to PHFBA alone. PMID:23953650

  12. Synergistic effect of the core-shell structured Sn/SnO2/C ternary anode system with the improved sodium storage performance

    NASA Astrophysics Data System (ADS)

    Cheng, Yayi; Huang, Jianfeng; Li, Jiayin; Xu, Zhanwei; Cao, Liyun; Qi, Hui

    2016-08-01

    Sn/SnO2/C ternary composite with core-shell structures is synthesized using a hydrothermal method and subsequent heat treatment at 973 K. This Sn/SnO2/C composite exhibits the micro-sphere structure that nanosized Sn and SnO2 particles are well encapsulated in the carbon matrix. As anode for sodium-ion batteries, the composite displays superior cycling stability and rate capability to SnO2/C and Sn/C composites. It delivers a high initial discharge capacity of 1110 mAh g-1 with good cyclability. Even at a high current density of 1000 mA g-1, a reversible capacity of 120 mAh g-1 is still remained. The enhanced sodium storage performance of Sn/SnO2/C anode is attributed to the synergistic effect provided by Sn, SnO2 and unique core-shell structure. Since the deformation of Sn can increase the reversible capacity of the SnO2 electrode and the carbon matrix could act as a buffer to accommodate the volume change.

  13. Synergistic effect of the core-shell structured Sn/SnO2/C ternary anode system with the improved sodium storage performance

    NASA Astrophysics Data System (ADS)

    Cheng, Yayi; Huang, Jianfeng; Li, Jiayin; Xu, Zhanwei; Cao, Liyun; Qi, Hui

    2016-08-01

    Sn/SnO2/C ternary composite with core-shell structures is synthesized using a hydrothermal method and subsequent heat treatment at 973 K. This Sn/SnO2/C composite exhibits the micro-sphere structure that nanosized Sn and SnO2 particles are well encapsulated in the carbon matrix. As anode for sodium-ion batteries, the composite displays superior cycling stability and rate capability to SnO2/C and Sn/C composites. It delivers a high initial discharge capacity of 1110 mAh g-1 with good cyclability. Even at a high current density of 1000 mA g-1, a reversible capacity of 120 mAh g-1 is still remained. The enhanced sodium storage performance of Sn/SnO2/C anode is attributed to the synergistic effect provided by Sn, SnO2 and unique core-shell structure. Since the deformation of Sn can increase the reversible capacity of the SnO2 electrode and the carbon matrix could act as a buffer to accommodate the volume change.

  14. Tailor-made polyfluoroacrylate and its block copolymer by RAFT polymerization in miniemulsion; improved hydrophobicity in the core-shell block copolymer.

    PubMed

    Chakrabarty, Arindam; Singha, Nikhil K

    2013-10-15

    Controlled/living radical polymerization (CRP) of a fluoroacrylate was successfully carried out in miniemulsion by Reversible Addition Fragmentation chain Transfer (RAFT) process. In this case, 2,2,3,3,4,4,4-heptafluorobutyl acrylate (HFBA) was polymerized using 2-cyanopropyl dodecyl trithiocarbonate (CPDTC) as RAFT agent, Triton X-405 and sodium dodecyl sulfonate (SDS) as surfactant, and potassium persulphate (KPS) or 2,2'-azobis isobutyronitrile (AIBN) as initiator. Being compatible with hydrophobic fluoroacrylate, this RAFT agent offered very high conversion and good control over the molecular weight of the polymer. The miniemulsion was stable without any costabilizer. The long chain dodecyl group (-C12H25) (Z-group in the RAFT agent) had beneficial effect in stabilizing the miniemulsion. When 2-cyano 2-propyl benzodithioate (CPBD) (Z=-C6H5) was used as RAFT agent, the conversion was less and particle size distribution was very broad. Block copolymerization with butyl acrylate (BA) using PHFBA as macro-RAFT agent showed core-shell morphology with the aggregation of PHFBA segment in the shell. GPC as well as DSC analysis confirmed the formation of block copolymer. The core-shell morphology was confirmed by TEM analysis. The block copolymers (PHFBA-b-PBA) showed significantly higher water contact angle (WCA) showing much better hydrophobicity compared to PHFBA alone.

  15. P-si nanowires/n-ZnO thin film based core-shell heterojunction diodes with improved effective Richardson constant.

    PubMed

    Hazra, Purnima; Jit, S

    2014-07-01

    This paper reports the temperature dependent electrical parameters of p-Silicon nanowires (SiNWs)/n-ZnO thin film based core-shell heterojunction diodes fabricated by conformally deposited zinc oxide (ZnO) by atomic layer deposition (ALD) technique on metal-assisted chemically etched SiNWs. The temperature-dependent current-voltage characteristics of the device have been estimated using the modified thermionic emission model in which a Gaussian distributed barrier height function is assumed to include the effects of barrier inhomogeneity phenomenon at the p-SiNW /n-ZnO heterojunction interface. Various parameters such as the turn-on voltage, ideality factor (eta), barrier height (phi(b)) and reverse saturation current are estimated over the operating temperature range of 303 K to 423 K of the diode. The value of the Richardson constant is observed to be largely changed from an impractical value of 1.989 x 10(-6) A cm(-2) K-2 to a realistic value of 36.6 A cm(-2) K-2 once the barrier inhogeneity phenomenon is taken into consideration in the analysis. The estimated value of the Richardson constant is believed to be the best among the reported results. The study is also believed to be the first in case of p-SiNWs/n-ZnO core-shell heterojunction diodes.

  16. A Search for Gravitationally Bound Cloud Cores within the CMZ

    NASA Astrophysics Data System (ADS)

    Gehret, Elizabeth; Battersby, Cara

    2016-01-01

    In general, current star formation theories successfully model the rate at which stars are forming throughout our Galaxy as well as others, with the star formation rate (SFR) in a given region being proportional to the amount of gas above a threshold density. The Central Molecular Zone (CMZ) of our Galaxy is an excellent place to test these models. It is home to the highest amount of dense, molecular gas within our Galaxy-and yet, the SFR within this region is an order of magnitude lower than would be expected using current star formation models. This project utilizes data taken from the SMA Legacy Survey of the CMZ, in a search for gravitationally bound structures within three small gas clouds near the Galactic Center, as well as the 1.6 degree cloud. Dense gas structures are detected using H2CO-a dense gas tracer, and 1.3mm cold, dust continuum. These regions are catalogued using dendrograms to identify which structures have continuous and significant H2CO emission. Gravitationally bound candidates were identified by deriving each structure's virial ratio. Within the three clouds near the GC, 40 structures were catalogued, with one structure that was found to be gravitationally bound. Very large virial ratios are the result of large H2CO line widths, possibly due to a high degree of tidal compression. This analysis is also performed on the 1.6 degree cloud, in a region with two suspected bound cores. One of these two cores is close to virial equilibrium and likely gravitationally bound, thus providing support for the use of this method on other clouds within the CMZ. This work supported in part by the NSF REU and DoD ASSURE programs under grant no. 1262851 and by the Smithsonian Institution.

  17. Mercury's Core

    NASA Astrophysics Data System (ADS)

    Peale, S. J.

    2005-05-01

    In determining Mercury's core structure from its rotational properties, the location of Cassini state 1 is crucial. Convincing radar evidence indicates that the mantle rests on a liquid layer (Margot et al. 2005), but there are no empirical constraints on the moment of inertia C/MR2, which constraints must wait for the determination of the gravitational coefficients J2 and C22 from the MESSENGER orbiting spacecraft, and an accurate determination of the obliquity of the Cassini state. Tidal and core-mantle dissipation drive the spin to the Cassini state with a time scale O(105) years, so the spin should occupy the Cassini state and thereby define its obliquity---unless there has been a recent excitation of a free precession of the spin. Another way the spin might be displaced from the Cassini state is if the variations in the orbital elements, which change the position of the Cassini state, cause the spin axis to lag behind as it attempts to follow the state. Fortunately, the solid angle the spin axis encloses as it precesses around the Cassini state is an adiabatic invariant, and it is conserved if the orbital element variations are slow compared to the precession rate. As the precession period is O(1000) years, and the time scales of orbital parameter variations are O(105) years, the spin axis should remain very close to the Cassini state if it were ever close. But how close is close? The increasing precision of the radar and eventual spacecraft measurements warrants a check on the likely proximity of the spin axis to the Cassini state. By numerically following the positions of the spin axis and Cassini state with orbital parameters varying with time scales and amplitudes comparable to the real variations, we show that the spin should remain within 1″ of the Cassini state once dissipative torques bring it there. The current spin axis position should thus define the Cassini state sufficiently to put reasonably tight constraints on the core structure

  18. The Relation between Cool Cluster Cores and Herschel-detected Star Formation in Brightest Cluster Galaxies

    NASA Astrophysics Data System (ADS)

    Rawle, T. D.; Edge, A. C.; Egami, E.; Rex, M.; Smith, G. P.; Altieri, B.; Fiedler, A.; Haines, C. P.; Pereira, M. J.; Pérez-González, P. G.; Portouw, J.; Valtchanov, I.; Walth, G.; van der Werf, P. P.; Zemcov, M.

    2012-03-01

    We present far-infrared (FIR) analysis of 68 brightest cluster galaxies (BCGs) at 0.08 < z < 1.0. Deriving total infrared luminosities directly from Spitzer and Herschel photometry spanning the peak of the dust component (24-500 μm), we calculate the obscured star formation rate (SFR). 22+6.2 -5.3% of the BCGs are detected in the far-infrared, with SFR = 1-150 M ⊙ yr-1. The infrared luminosity is highly correlated with cluster X-ray gas cooling times for cool-core clusters (gas cooling time <1 Gyr), strongly suggesting that the star formation in these BCGs is influenced by the cluster-scale cooling process. The occurrence of the molecular gas tracing Hα emission is also correlated with obscured star formation. For all but the most luminous BCGs (L TIR > 2 × 1011 L ⊙), only a small (lsim0.4 mag) reddening correction is required for SFR(Hα) to agree with SFRFIR. The relatively low Hα extinction (dust obscuration), compared to values reported for the general star-forming population, lends further weight to an alternate (external) origin for the cold gas. Finally, we use a stacking analysis of non-cool-core clusters to show that the majority of the fuel for star formation in the FIR-bright BCGs is unlikely to originate from normal stellar mass loss. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  19. The Percent of Positive Biopsy Cores Improves Prediction of Prostate Cancer-Specific Death in Patients Treated With Dose-Escalated Radiotherapy

    SciTech Connect

    Qian Yushen; Feng, Felix Y.; Halverson, Schuyler; Blas, Kevin; Sandler, Howard M.; Hamstra, Daniel A.

    2011-11-01

    Purpose: To examine the prognostic utility of the percentage of positive cores (PPC) at the time of prostate biopsy for patients treated with dose-escalated external beam radiation therapy. Methods and Materials: We performed a retrospective analysis of patients treated at University of Michigan Medical Center to at least 75 Gy. Patients were stratified according to PPC by quartile, and freedom from biochemical failure (nadir + 2 ng/mL), freedom from metastasis (FFM), cause-specific survival (CSS), and overall survival (OS) were assessed by log-rank test. Receiver operator characteristic (ROC) curve analysis was used to determine the optimal cut point for PPC stratification. Finally, Cox proportional hazards multivariate regression was used to assess the impact of PPC on clinical outcome when adjusting for National Comprehensive Cancer Network (NCCN) risk group and androgen deprivation therapy. Results: PPC information was available for 651 patients. Increasing-risk features including T stage, prostate-specific antigen, Gleason score, and NCCN risk group were all directly correlated with increasing PPC. On log-rank evaluation, all clinical endpoints, except for OS, were associated with PPC by quartile, with worse clinical outcomes as PPC increased, with the greatest impact seen in the highest quartile (>66.7% of cores positive). ROC curve analysis confirmed that a cut point using two-thirds positive cores was most closely associated with CSS (p = 0.002; area under ROC curve, 0.71). On univariate analysis, stratifying patients according to PPC less than or equal to 66.7% vs. PPC greater than 66.7% was prognostic for freedom from biochemical failure (p = 0.0001), FFM (p = 0.0002), and CSS (p = 0.0003) and marginally prognostic for OS (p = 0.055). On multivariate analysis, after adjustment for NCCN risk group and androgen deprivation therapy use, PPC greater than 66.7% increased the risk for biochemical failure (p = 0.0001; hazard ratio [HR], 2.1 [95% confidence

  20. Core Journal Lists: Classic Tool, New Relevance

    ERIC Educational Resources Information Center

    Paynter, Robin A.; Jackson, Rose M.; Mullen, Laura Bowering

    2010-01-01

    Reviews the historical context of core journal lists, current uses in collection assessment, and existing methodologies for creating lists. Outlines two next generation core list projects developing new methodologies and integrating novel information/data sources to improve precision: a national-level core psychology list and the other a local…

  1. Use of a small particle solid-core packing for improved efficiency and rapid measurement of sirolimus and everolimus by LC-MS/MS.

    PubMed

    Morgan, Phillip; Nwafor, Magnus; Tredger, Mike

    2016-06-01

    Measurement of whole blood sirolimus and everolimus is required in order to optimize patient treatment following solid organ transplant. Assay by LC-MS/MS is increasingly preferred; however efficient use of the instrument and short turnaround times are crucial. Use of a 1.6 µm solid-core packing HPLC column (Cortecs) gave significant increases in efficiency, sensitivity and throughput compared with an existing method, following simple protein precipitation of small-volume (20 μL) whole blood samples. Sirolimus, everolimus and the stable isotopic internal standard ((13) C2 D4 - everolimus) eluted at around 0.8 min, and total analytical run time was 2.2 min, saving almost 4 min per sample compared with an existing method. Within-assay imprecision (CV) was 3.3-8.5%, and between-assay imprecision was 2.2-10.8%. Retrospective assay of external quality assurance samples and comparison of patient samples assayed in parallel showed only small differences (between +6.8 and -1.9%) in results using the Cortecs column when compared with the existing method. No significant interferences or ion suppression were observed. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Improved room-temperature luminescence of core-shell InGaAs/GaAs nanopillars via lattice-matched passivation

    NASA Astrophysics Data System (ADS)

    Komolibus, Katarzyna; Scofield, Adam C.; Gradkowski, Kamil; Ochalski, Tomasz J.; Kim, Hyunseok; Huffaker, Diana L.; Huyet, Guillaume

    2016-02-01

    Optical properties of GaAs/InGaAs/GaAs nanopillars (NPs) grown on GaAs(111)B were investigated. Employment of a mask-etching technique allowed for an accurate control over the geometry of NP arrays in terms of both their diameter and separation. This work describes both the steady-state and time-resolved photoluminescence of these structures as a function of the ensemble geometry, composition of the insert, and various shell compounds. The effects of the NP geometry on a parasitic radiative recombination channel, originating from an overgrown lateral sidewall layer, are discussed. Optical characterization reveals a profound influence of the core-shell lattice mismatch on the carrier lifetime and emission quenching at room temperature. When the lattice-matching conditions are satisfied, an efficient emission from the NP arrays at room temperature and below the band-gap of silicon is observed, clearly highlighting their potential application as emitters in optical interconnects integrated with silicon platforms.

  3. Dual-core antiresonant hollow core fibers.

    PubMed

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters.

  4. Core-collapse Supernovae

    SciTech Connect

    Hix, William Raphael; Lentz, E. J.; Baird, Mark L; Chertkow, Merek A; Lee, Ching-Tsai; Blondin, J. M.; Bruenn, S. W.; Messer, Bronson; Mezzacappa, Anthony

    2013-01-01

    Marking the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae bring together physics at a wide range in spatial scales, from kilometer-sized hydrodynamic motions (growing to gigameter scale) down to femtometer scale nuclear reactions. Carrying 10$^{51}$ ergs of kinetic energy and a rich-mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up ourselves and our solar system. We will discuss our emerging understanding of the convectively unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino-radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Recent multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of how supernovae explode. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  5. Optical fiber sensor having an active core

    NASA Technical Reports Server (NTRS)

    Egalon, Claudio Oliveira (Inventor); Rogowski, Robert S. (Inventor)

    1993-01-01

    An optical fiber is provided. The fiber is comprised of an active fiber core which produces waves of light upon excitation. A factor ka is identified and increased until a desired improvement in power efficiency is obtained. The variable a is the radius of the active fiber core and k is defined as 2 pi/lambda wherein lambda is the wavelength of the light produced by the active fiber core. In one embodiment, the factor ka is increased until the power efficiency stabilizes. In addition to a bare fiber core embodiment, a two-stage fluorescent fiber is provided wherein an active cladding surrounds a portion of the active fiber core having an improved ka factor. The power efficiency of the embodiment is further improved by increasing a difference between the respective indices of refraction of the active cladding and the active fiber core.

  6. Core Stability Training for Injury Prevention

    PubMed Central

    Huxel Bliven, Kellie C.; Anderson, Barton E.

    2013-01-01

    Context: Enhancing core stability through exercise is common to musculoskeletal injury prevention programs. Definitive evidence demonstrating an association between core instability and injury is lacking; however, multifaceted prevention programs including core stabilization exercises appear to be effective at reducing lower extremity injury rates. Evidence Acquisition: PubMed was searched for epidemiologic, biomechanic, and clinical studies of core stability for injury prevention (keywords: “core OR trunk” AND “training OR prevention OR exercise OR rehabilitation” AND “risk OR prevalence”) published between January 1980 and October 2012. Articles with relevance to core stability risk factors, assessment, and training were reviewed. Relevant sources from articles were also retrieved and reviewed. Results: Stabilizer, mobilizer, and load transfer core muscles assist in understanding injury risk, assessing core muscle function, and developing injury prevention programs. Moderate evidence of alterations in core muscle recruitment and injury risk exists. Assessment tools to identify deficits in volitional muscle contraction, isometric muscle endurance, stabilization, and movement patterns are available. Exercise programs to improve core stability should focus on muscle activation, neuromuscular control, static stabilization, and dynamic stability. Conclusion: Core stabilization relies on instantaneous integration among passive, active, and neural control subsystems. Core muscles are often categorized functionally on the basis of stabilizing or mobilizing roles. Neuromuscular control is critical in coordinating this complex system for dynamic stabilization. Comprehensive assessment and training require a multifaceted approach to address core muscle strength, endurance, and recruitment requirements for functional demands associated with daily activities, exercise, and sport. PMID:24427426

  7. Structure-Based Engineering of Methionine Residues in the Catalytic Cores of Alkaline Amylase from Alkalimonas amylolytica for Improved Oxidative Stability

    PubMed Central

    Yang, Haiquan; Wang, Mingxing; Li, Jianghua; Wang, Nam Sun; Du, Guocheng

    2012-01-01

    This work aims to improve the oxidative stability of alkaline amylase from Alkalimonas amylolytica through structure-based site-directed mutagenesis. Based on an analysis of the tertiary structure, five methionines (Met 145, Met 214, Met 229, Met 247, and Met 317) were selected as the mutation sites and individually replaced with leucine. In the presence of 500 mM H2O2 at 35°C for 5 h, the wild-type enzyme and the M145L, M214L, M229L, M247L, and M317L mutants retained 10%, 28%, 46%, 28%, 72%, and 43% of the original activity, respectively. Concomitantly, the alkaline stability, thermal stability, and catalytic efficiency of the M247L mutant were also improved. The pH stability of the mutants (M145L, M214L, M229L, and M317L) remained unchanged compared to that of the wild-type enzyme, while the stable pH range of the M247L mutant was extended from pH 7.0 to 11.0 for the wild type to pH 6.0 to 12.0 for the mutant. The wild-type enzyme lost its activity after incubation at 50°C for 2 h, and the M145L, M214L, M229L, and M317L mutants retained less than 14% of the activity, whereas the M247L mutant retained 34% of the activity under the same conditions. Compared to the wild-type enzyme, the kcat values of the M145L, M214L, M229L, and M317L mutants decreased, while that of the M247L mutant increased slightly from 5.0 × 104 to 5.6 × 104 min−1. The mechanism responsible for the increased oxidative stability, alkaline stability, thermal stability, and catalytic efficiency of the M247L mutant was further analyzed with a structure model. The combinational mutants were also constructed, and their biochemical properties were characterized. The resistance of the wild-type enzyme and the mutants to surfactants and detergents was also investigated. Our results indicate that the M247L mutant has great potential in the detergent and textile industries. PMID:22865059

  8. Cooling, AGN Feedback, and Star Formation in Simulated Cool-core Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Li, Yuan; Bryan, Greg L.; Ruszkowski, Mateusz; Voit, G. Mark; O’Shea, Brian W.; Donahue, Megan

    2015-10-01

    Numerical simulations of active galactic nuclei (AGNs) feedback in cool-core galaxy clusters have successfully avoided classical cooling flows, but often produce too much cold gas. We perform adaptive mesh simulations that include momentum-driven AGN feedback, self-gravity, star formation, and stellar feedback, focusing on the interplay between cooling, AGN heating, and star formation in an isolated cool-core cluster. Cold clumps triggered by AGN jets and turbulence form filamentary structures tens of kpc long. This cold gas feeds both star formation and the supermassive black hole (SMBH), triggering an AGN outburst that increases the entropy of the intracluster medium (ICM) and reduces its cooling rate. Within 1–2 Gyr, star formation completely consumes the cold gas, leading to a brief shutoff of the AGN. The ICM quickly cools and redevelops multiphase gas, followed by another cycle of star formation/AGN outburst. Within 6.5 Gyr, we observe three such cycles. There is good agreement between our simulated cluster and the observations of cool-core clusters. ICM cooling is dynamically balanced by AGN heating, and a cool-core appearance is preserved. The minimum cooling time to free-fall time ratio typically varies between a few and ≳ 20. The star formation rate (SFR) covers a wide range, from 0 to a few hundred {M}ȯ {{yr}}-1, with an average of ∼ 40 {M}ȯ {{yr}}-1. The instantaneous SMBH accretion rate shows large variations on short timescales, but the average value correlates well with the SFR. Simulations without stellar feedback or self-gravity produce qualitatively similar results, but a lower SMBH feedback efficiency (0.1% compared to 1%) results in too many stars.

  9. Core Competencies: What They Are and How To Use Them.

    ERIC Educational Resources Information Center

    Naylor, Richard J.

    2000-01-01

    Describes characteristics of core competencies. Examines the competencies a librarian should possess. Discusses types of competence and reviews advantages of developing and improving core competencies. Looks at core competencies in terms of the major service areas of public libraries. Presents several steps for building core competencies.…

  10. Core-core and core-valence correlation

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1988-01-01

    The effect of (1s) core correlation on properties and energy separations was analyzed using full configuration-interaction (FCI) calculations. The Be 1 S - 1 P, the C 3 P - 5 S and CH+ 1 Sigma + or - 1 Pi separations, and CH+ spectroscopic constants, dipole moment and 1 Sigma + - 1 Pi transition dipole moment were studied. The results of the FCI calculations are compared to those obtained using approximate methods. In addition, the generation of atomic natural orbital (ANO) basis sets, as a method for contracting a primitive basis set for both valence and core correlation, is discussed. When both core-core and core-valence correlation are included in the calculation, no suitable truncated CI approach consistently reproduces the FCI, and contraction of the basis set is very difficult. If the (nearly constant) core-core correlation is eliminated, and only the core-valence correlation is included, CASSCF/MRCI approached reproduce the FCI results and basis set contraction is significantly easier.

  11. Status of the core and the mini core collections for the U.S. gemrplasm collection of peanut

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To maximize their usefulness, core and mini core collections should be dynamic. The peanut core collection was developed in the early 1990's, and the mini core was developed in the late 1990's. Research has shown that these collections can be used to improve the efficiency and effectiveness of ide...

  12. Eleventh-Grade Core Program.

    ERIC Educational Resources Information Center

    Van Voorhees, Sylvia; Scoblete, Frank

    Designed to improve reading skills of nonacademic high school juniors and to encourage positive attitudes toward racial and ethnic differences, an English and social studies core program was developed. Two groups of students, one of disabled readers and one of better but unmotivated readers, received one period of instruction in English and one in…

  13. Horizontal core acquisition and orientation for formation evaluation

    SciTech Connect

    Skopec, R.A. ); Mann, M.M. ); Grier, S.P. )

    1992-03-01

    The increase in horizontal drilling activity has produced a need for improved coring technology. The development of a reliable horizontal (medium-radius) coring and orientation system has greatly improved the acquisition of information necessary for formation evaluation and reservoir engineering. This paper describes newly developed hardware and methods for obtaining horizontal core sections.

  14. Discovery of a Galaxy Cluster with a Violently Starbursting Core at z = 2.506

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Elbaz, David; Daddi, Emanuele; Finoguenov, Alexis; Liu, Daizhong; Schreiber, Corentin; Martín, Sergio; Strazzullo, Veronica; Valentino, Francesco; van der Burg, Remco; Zanella, Anita; Ciesla, Laure; Gobat, Raphael; Le Brun, Amandine; Pannella, Maurilio; Sargent, Mark; Shu, Xinwen; Tan, Qinghua; Cappelluti, Nico; Li, Yanxia

    2016-09-01

    We report the discovery of a remarkable concentration of massive galaxies with extended X-ray emission at z spec = 2.506, which contains 11 massive (M * ≳ 1011 M ⊙) galaxies in the central 80 kpc region (11.6σ overdensity). We have spectroscopically confirmed 17 member galaxies with 11 from CO and the remaining ones from Hα. The X-ray luminosity, stellar mass content, and velocity dispersion all point to a collapsed, cluster-sized dark matter halo with mass M 200c = 1013.9±0.2 M ⊙, making it the most distant X-ray-detected cluster known to date. Unlike other clusters discovered so far, this structure is dominated by star-forming galaxies (SFGs) in the core with only 2 out of the 11 massive galaxies classified as quiescent. The star formation rate (SFR) in the 80 kpc core reaches ˜3400 M ⊙ yr-1 with a gas depletion time of ˜200 Myr, suggesting that we caught this cluster in rapid build-up of a dense core. The high SFR is driven by both a high abundance of SFGs and a higher starburst fraction (˜25%, compared to 3%-5% in the field). The presence of both a collapsed, cluster-sized halo and a predominant population of massive SFGs suggests that this structure could represent an important transition phase between protoclusters and mature clusters. It provides evidence that the main phase of massive galaxy passivization will take place after galaxies accrete onto the cluster, providing new insights into massive cluster formation at early epochs. The large integrated stellar mass at such high redshift challenges our understanding of massive cluster formation.

  15. NEUTRONIC REACTOR CORE

    DOEpatents

    Thomson, W.B.; Corbin, A. Jr.

    1961-07-18

    An improved core for a gas-cooled power reactor which admits gas coolant at high temperatures while affording strong integral supporting structure and efficient moderation of neutrons is described. The multiplicities of fuel elements constituting the critical amassment of fissionable material are supported and confined by a matrix of metallic structure which is interspersed therebetween. Thermal insulation is interposed between substantially all of the metallic matrix and the fuel elements; the insulation then defines the principal conduit system for conducting the coolant gas in heat-transfer relationship with the fuel elements. The metallic matrix itseif comprises a system of ducts through which an externally-cooled hydrogeneous liquid, such as water, is circulated to serve as the principal neutron moderant for the core and conjointly as the principal coolant for the insulated metallic structure. In this way, use of substantially neutron transparent metals, such as aluminum, becomes possible for the supporting structure, despite the high temperatures of the proximate gas. The Aircraft Nuclear Propulsion program's "R-1" reactor design is a preferred embodiment.

  16. Academic Rigor: The Core of the Core

    ERIC Educational Resources Information Center

    Brunner, Judy

    2013-01-01

    Some educators see the Common Core State Standards as reason for stress, most recognize the positive possibilities associated with them and are willing to make the professional commitment to implementing them so that academic rigor for all students will increase. But business leaders, parents, and the authors of the Common Core are not the only…

  17. Development and first application of a new tool for the simulation of the initiating phase of a severe accident on SFR

    NASA Astrophysics Data System (ADS)

    Guyot, M.; Gubernatis, P.; Suteau, C.

    2014-06-01

    In order to improve the safety level of Sodium Fast Reactors, low probability events such as Hypothetical Core Disruptive Accident (HCDA) are analyzed for their potential consequences. The initiating phase of such accidents is of particular interest both for the prevention and the mitigation of routes leading to a large core disruption and recriticalities. Up to now, analysis of the initiating phase of HCDA has been performed with the SAS4A code. The SAS4A accident calculations are based on a multiple-channel approach, which requires that subassemblies or groups of similar subassemblies be represented together as independent channels. The SAS4A severe accident calculation scheme resorts to a simplified treatment in which an average pin is used to represent a channel. A point kinetics model coupled with a feedback reactivity model is also used to provide an estimate of the reactor power level. Both to increase the accuracy and decrease the uncertainties in the prediction of reactor safety margins, a new computational tool is currently under development at CEA Cadarache. The main features of this tool are the ability to provide a detailed sub-channel meshing of the sub-assembly as well as three-dimensional kinetics during severe accident conditions. To fulfill these goals, the fluid-dynamics SIMMER-III code has been coupled to the SNATCH solver using a MPI environment. This coupling allows both to compute the multi-phase and multi-component flows encountered in severe accident conditions and to model the power shape variation during voiding and melting of the different reactor materials. This new calculation scheme relies on a SAS-like multiple-channel treatment, where channel-to-channel heat and momentum exchanges are neglected. In this paper, an overview of the SIMMER-III/SNATCH coupled tool capabilities is provided. A first application of this new tool is also performed and compared with a SAS4A reference calculation. The new SIMMER-III/SNATCH tool proved to be

  18. Common Core in the Real World

    ERIC Educational Resources Information Center

    Hess, Frederick M.; McShane, Michael Q.

    2013-01-01

    There are at least four key places where the Common Core intersects with current efforts to improve education in the United States--testing, professional development, expectations, and accountability. Understanding them can help educators, parents, and policymakers maximize the chance that the Common Core is helpful to these efforts and, perhaps…

  19. List of Core Journals in Earth Sciences.

    ERIC Educational Resources Information Center

    International Council for Scientific and Technical Information, Paris (France).

    Selection and acquisition of relevant materials for building and developing an information infrastructure are modern worldwide problems. This document provides a core listing of journals in the earth sciences in an effort to develop a tool for the improvement of information handling and transfer. The core list was generated using several databases…

  20. Core-shell GaN-ZnO moth-eye nanostructure arrays grown on a-SiO2/Si (1 1 1) as a basis for improved InGaN-based photovoltaics and LEDs

    NASA Astrophysics Data System (ADS)

    Rogers, D. J.; Sandana, V. E.; Gautier, S.; Moudakir, T.; Abid, M.; Ougazzaden, A.; Teherani, F. Hosseini; Bove, P.; Molinari, M.; Troyon, M.; Peres, M.; Soares, Manuel J.; Neves, A. J.; Monteiro, T.; McGrouther, D.; Chapman, J. N.; Drouhin, H.-J.; McClintock, R.; Razeghi, M.

    2015-06-01

    Self-forming, vertically-aligned, ZnO moth-eye-like nanoarrays were grown by catalyst-free pulsed laser deposition on a-SiO2/Si (1 1 1) substrates. X-Ray Diffraction (XRD) and Cathodoluminescence (CL) studies indicated that nanostructures were highly c-axis oriented wurtzite ZnO with strong near band edge emission. The nanostructures were used as templates for the growth of non-polar GaN by metal organic vapor phase epitaxy. XRD, scanning electron microscopy, energy dispersive X-ray microanalysis and CL revealed ZnO encapsulated with GaN, without evidence of ZnO back-etching. XRD showed compressive epitaxial strain in the GaN, which is conducive to stabilization of the higher indium contents required for more efficient green light emitting diode (LED) and photovoltaic (PV) operation. Angular-dependent specular reflection measurements showed a relative reflectance of less than 1% over the wavelength range of 400-720 nm at all angles up to 60°. The superior black-body performance of this moth-eye-like structure would boost LED light extraction and PV anti-reflection performance compared with existing planar or nanowire LED and PV morphologies. The enhancement in core conductivity, provided by the ZnO, would also improve current distribution and increase the effective junction area compared with nanowire devices based solely on GaN.

  1. Core Design Applications

    1995-07-12

    CORD-2 is intended for core desigh applications of pressurized water reactors. The main objective was to assemble a core design system which could be used for simple calculations (such as frequently required for fuel management) as well as for accurate calculations (for example, core design after refueling).

  2. Core to College Evaluation: Exploring the Use of Multiple Measures for Placement into College-Level Courses. Seeking Alternatives or Improvements to the Use of a Single Standardized Test

    ERIC Educational Resources Information Center

    Bracco, Kathy Reeves; Dadgar, Mina; Austin, Kim; Klarin, Becca; Broek, Marie; Finkelstein, Neal; Mundry, Susan; Bugler, Dan

    2014-01-01

    "Core to College: Preparing Students for College Readiness and Success" is a three-year initiative. The initiative's mission is to "facilitate greater coordination between K-12 and postsecondary education systems around implementation of the Common Core State Standards (CCSS) and aligned assessments." Its aim is to foster…

  3. Banded transformer cores

    NASA Technical Reports Server (NTRS)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  4. HYDRATE CORE DRILLING TESTS

    SciTech Connect

    John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

    2002-11-01

    The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate formation comprised of coarse, large

  5. 23. CORE WORKER OPERATING A COREBLOWER THAT PNEUMATICALLY FILLED CORE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. CORE WORKER OPERATING A CORE-BLOWER THAT PNEUMATICALLY FILLED CORE BOXES WITH RESIGN IMPREGNATED SAND AND CREATED A CORE THAT THEN REQUIRED BAKING, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  6. Core-Cutoff Tool

    NASA Technical Reports Server (NTRS)

    Gheen, Darrell

    2007-01-01

    A tool makes a cut perpendicular to the cylindrical axis of a core hole at a predetermined depth to free the core at that depth. The tool does not damage the surrounding material from which the core was cut, and it operates within the core-hole kerf. Coring usually begins with use of a hole saw or a hollow cylindrical abrasive cutting tool to make an annular hole that leaves the core (sometimes called the plug ) in place. In this approach to coring as practiced heretofore, the core is removed forcibly in a manner chosen to shear the core, preferably at or near the greatest depth of the core hole. Unfortunately, such forcible removal often damages both the core and the surrounding material (see Figure 1). In an alternative prior approach, especially applicable to toxic or fragile material, a core is formed and freed by means of milling operations that generate much material waste. In contrast, the present tool eliminates the damage associated with the hole-saw approach and reduces the extent of milling operations (and, hence, reduces the waste) associated with the milling approach. The present tool (see Figure 2) includes an inner sleeve and an outer sleeve and resembles the hollow cylindrical tool used to cut the core hole. The sleeves are thin enough that this tool fits within the kerf of the core hole. The inner sleeve is attached to a shaft that, in turn, can be attached to a drill motor or handle for turning the tool. This tool also includes a cutting wire attached to the distal ends of both sleeves. The cutting wire is long enough that with sufficient relative rotation of the inner and outer sleeves, the wire can cut all the way to the center of the core. The tool is inserted in the kerf until its distal end is seated at the full depth. The inner sleeve is then turned. During turning, frictional drag on the outer core pulls the cutting wire into contact with the core. The cutting force of the wire against the core increases with the tension in the wire and

  7. Core sample extractor

    NASA Technical Reports Server (NTRS)

    Akins, James; Cobb, Billy; Hart, Steve; Leaptrotte, Jeff; Milhollin, James; Pernik, Mark

    1989-01-01

    The problem of retrieving and storing core samples from a hole drilled on the lunar surface is addressed. The total depth of the hole in question is 50 meters with a maximum diameter of 100 millimeters. The core sample itself has a diameter of 60 millimeters and will be two meters in length. It is therefore necessary to retrieve and store 25 core samples per hole. The design utilizes a control system that will stop the mechanism at a certain depth, a cam-linkage system that will fracture the core, and a storage system that will save and catalogue the cores to be extracted. The Rod Changer and Storage Design Group will provide the necessary tooling to get into the hole as well as to the core. The mechanical design for the cam-linkage system as well as the conceptual design of the storage device are described.

  8. Teaching to the Core: Integrating Implementation of Common Core and Teacher Effectiveness Policies

    ERIC Educational Resources Information Center

    Wiener, Ross

    2013-01-01

    The purpose of the Common Core State Standards is to prepare students to succeed in college and career pursuits. To that end, the Common Core calls on teachers to focus on deepening students' understanding of what they're learning, enhancing their problem-solving skills, and improving their ability to communicate ideas. At the same time, states…

  9. The core paradox.

    NASA Technical Reports Server (NTRS)

    Kennedy, G. C.; Higgins, G. H.

    1973-01-01

    Rebuttal of suggestions from various critics attempting to provide an escape from the seeming paradox originated by Higgins and Kennedy's (1971) proposed possibility that the liquid in the outer core was thermally stably stratified and that this stratification might prove a powerful inhibitor to circulation of the outer core fluid of the kind postulated for the generation of the earth's magnetic field. These suggestions are examined and shown to provide no reasonable escape from the core paradox.

  10. Core-core and core-valence correlation

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1988-01-01

    The effect of 1s core correlation on properties and energy separations are analyzed using full configuration-interaction (FCI) calculations. The Be1S - 1P, the C 3P - 5S,m and CH(+) 1Sigma(+) - 1Pi separations, and CH(+) spectroscopic constants, dipole moment, and 1Sigma(+) - 1Pi transition dipole moment have been studied. The results of the FCI calculations are compared to those obtained using approximate methods.

  11. AN Core Analysis

    NASA Astrophysics Data System (ADS)

    Barbarino, Andrea; Tomatis, Daniele

    2014-06-01

    Several alternative approximations of neutron transport have been proposed in years to move around the known limitations imposed by neutron diffusion in the modeling of nuclear cores. However, only a few complied with the industrial requirements of fast numerical computation, concentrating more on physical accuracy. In this work, the AN transport methodology is discussed with particular interest in core performance calculations. The implementation of the methodology in full core codes is discussed with particular attention to numerical issues and to the integration within the entire simulation process. Finally, first results from core studies in AN transport are analyzed in detail and compared to standard results of neutron diffusion.

  12. Core Research Center

    USGS Publications Warehouse

    Hicks, Joshua; Adrian, Betty

    2009-01-01

    The Core Research Center (CRC) of the U.S. Geological Survey (USGS), located at the Denver Federal Center in Lakewood, Colo., currently houses rock core from more than 8,500 boreholes representing about 1.7 million feet of rock core from 35 States and cuttings from 54,000 boreholes representing 238 million feet of drilling in 28 States. Although most of the boreholes are located in the Rocky Mountain region, the geologic and geographic diversity of samples have helped the CRC become one of the largest and most heavily used public core repositories in the United States. Many of the boreholes represented in the collection were drilled for energy and mineral exploration, and many of the cores and cuttings were donated to the CRC by private companies in these industries. Some cores and cuttings were collected by the USGS along with other government agencies. Approximately one-half of the cores are slabbed and photographed. More than 18,000 thin sections and a large volume of analytical data from the cores and cuttings are also accessible. A growing collection of digital images of the cores are also becoming available on the CRC Web site Internet http://geology.cr.usgs.gov/crc/.

  13. Development of New IP Cores for Spacecraft Avionics

    NASA Astrophysics Data System (ADS)

    Isomaki, Marko; Ekergarn, Jonas; Hjorth, Magnus; Wessman, Nils-Johan; Habinc, Sandi

    2010-08-01

    The GRLIB IP library is an integrated set of reusable IP cores, designed for system-on-chip (SOC) development. The IP cores are centered around a common on-chip bus, and use a coherent method for simulation and synthesis. The library is vendor independent, with support for different CAD tools and target technologies. The success of any IP core library is highly dependent on the constantly increasing number of IP cores and the improvement of existing IP cores. This paper will cover both these aspects, presenting some new developments as well as some improvements of existing items.

  14. Tapered polysilicon core fibers for nonlinear photonics.

    PubMed

    Suhailin, Fariza H; Shen, Li; Healy, Noel; Xiao, Limin; Jones, Maxwell; Hawkins, Thomas; Ballato, John; Gibson, Ursula J; Peacock, Anna C

    2016-04-01

    We propose and demonstrate a novel approach to obtaining small-core polysilicon waveguides from the silicon fiber platform. The fibers were fabricated via a conventional drawing tower method and, subsequently, tapered down to achieve silicon core diameters of ∼1  μm, the smallest optical cores for this class of fiber to date. Characterization of the material properties have shown that the taper process helps to improve the local crystallinity of the silicon core, resulting in a significant reduction in the material loss. By exploiting the combination of small cores and low losses, these tapered fibers have enabled the first observation of nonlinear transmission within a polycrystalline silicon waveguide of any type. As the fiber drawing method is highly scalable, it opens a route for the development of low-cost and flexible nonlinear silicon photonic systems. PMID:27192236

  15. Can Psychiatric Rehabilitation Be Core to CORE?

    ERIC Educational Resources Information Center

    Olney, Marjorie F.; Gill, Kenneth J.

    2016-01-01

    Purpose: In this article, we seek to determine whether psychiatric rehabilitation principles and practices have been more fully incorporated into the Council on Rehabilitation Education (CORE) standards, the extent to which they are covered in four rehabilitation counseling "foundations" textbooks, and how they are reflected in the…

  16. Coring in deep hardrock formations

    SciTech Connect

    Drumheller, D.S.

    1988-08-01

    The United States Department of Energy is involved in a variety of scientific and engineering feasibility studies requiring extensive drilling in hard crystalline rock. In many cases well depths extend from 6000 to 20,000 feet in high-temperature, granitic formations. Examples of such projects are the Hot Dry Rock well system at Fenton Hill, New Mexico and the planned exploratory magma well near Mammoth Lakes, California. In addition to these programs, there is also continuing interest in supporting programs to reduce drilling costs associated with the production of geothermal energy from underground sources such as the Geysers area near San Francisco, California. The overall progression in these efforts is to drill deeper holes in higher temperature, harder formations. In conjunction with this trend is a desire to improve the capability to recover geological information. Spot coring and continuous coring are important elements in this effort. It is the purpose of this report to examine the current methods used to obtain core from deep wells and to suggest projects which will improve existing capabilities. 28 refs., 8 figs., 2 tabs.

  17. Improved Performance of Dye-Sensitized Solar Cells Fabricated from a Coumarin NKX-2700 Dye-Sensitized TiO2/MgO Core-Shell Photoanode with an HfO2 Blocking Layer and a Quasi-Solid-State Electrolyte

    NASA Astrophysics Data System (ADS)

    Maheswari, D.; Venkatachalam, P.

    2015-03-01

    Dye sensitized solar cells (DSSC) were fabricated from a coumarin NKX-2700 dye-sensitized core-shell photoanode and a quasi-solid-state electrolyte, sandwiched together, with a cobalt sulfide-coated counter electrode. The core-shell photoanode consisted of a composite mixture of 90% TiO2 nanoparticles and 10% TiO2 nanowires (TNPW) as core layer and MgO nanoparticles (MNP) as shell layer. Hafnium oxide (HfO2) was applied to the core-shell photoanode film as a blocking layer. TiO2 nanoparticles, TiO2 nanowires, and TNPW/MNP were characterized by x-ray diffractometry, scanning electron microscopy, and transmission electron microscopy. It was apparent from the UV-visible spectrum of the sensitizing dye coumarin NKX-2700 that its absorption was maximum at 525 nm. Power conversion efficiency (PCE) was greater for DSSC-1, fabricated with a core-shell TNPW/MNP/HfO2 photoanode, than for the other DSSC; its photovoltaic properties were: short circuit photocurrent J sc = 19 mA/cm2, open circuit voltage ( V oc) = 720 mV, fill factor ( FF) = 66%, and PCE ( η) = 9.02%. The charge-transport and charge-recombination behavior of the DSSC were investigated by electrochemical impedance spectroscopy; the results showed that the composite core-shell film resulted in the lowest charge-transfer resistance ( R CE) and the longest electron lifetime ( τ eff). Hence, the improved performance of DSSC-1 could be ascribed to the core-shell photoanode with blocking layer, which increased electron transport and suppressed recombination of charge carriers at the photoanode/dye/electrolyte interface.

  18. Mercury's core evolution

    NASA Astrophysics Data System (ADS)

    Deproost, Marie-Hélène; Rivoldini, Attilio; Van Hoolst, Tim

    2016-10-01

    Remote sensing data of Mercury's surface by MESSENGER indicate that Mercury formed under reducing conditions. As a consequence, silicon is likely the main light element in the core together with a possible small fraction of sulfur. Compared to sulfur, which does almost not partition into solid iron at Mercury's core conditions and strongly decreases the melting temperature, silicon partitions almost equally well between solid and liquid iron and is not very effective at reducing the melting temperature of iron. Silicon as the major light element constituent instead of sulfur therefore implies a significantly higher core liquidus temperature and a decrease in the vigor of compositional convection generated by the release of light elements upon inner core formation.Due to the immiscibility in liquid Fe-Si-S at low pressure (below 15 GPa), the core might also not be homogeneous and consist of an inner S-poor Fe-Si core below a thinner Si-poor Fe-S layer. Here, we study the consequences of a silicon-rich core and the effect of the blanketing Fe-S layer on the thermal evolution of Mercury's core and on the generation of a magnetic field.

  19. Ice Core Investigations

    ERIC Educational Resources Information Center

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  20. NFE Core Bibliographies.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Inst. for International Studies in Education.

    This collection of core bibliographies, which expands on an initial bibliography published in 1979 of the core resources housed in the Non-Formal Education Information Center at Michigan State University, comprises a basic stock of materials on nonformal education and women in development that have been contributed by development planners,…

  1. CORE - Performance Feedback System

    SciTech Connect

    2009-10-02

    CORE is an architecture to bridge the gaps between disparate data integration and delivery of disparate information visualization. The CORE Technology Program includes a suite of tools and user-centered staff that can facilitate rapid delivery of a deployable integrated information to users.

  2. Iowa Core Annual Report

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2015

    2015-01-01

    One central component of a great school system is a clear set of expectations, or standards, that educators help all students reach. In Iowa, that effort is known as the Iowa Core. The Iowa Core represents the statewide academic standards, which describe what students should know and be able to do in math, science, English language arts, and…

  3. Making an Ice Core.

    ERIC Educational Resources Information Center

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  4. Discovery of a Galaxy Cluster with a Violently Starbursting Core at z = 2.506

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Elbaz, David; Daddi, Emanuele; Finoguenov, Alexis; Liu, Daizhong; Schreiber, Corentin; Martín, Sergio; Strazzullo, Veronica; Valentino, Francesco; van der Burg, Remco; Zanella, Anita; Ciesla, Laure; Gobat, Raphael; Le Brun, Amandine; Pannella, Maurilio; Sargent, Mark; Shu, Xinwen; Tan, Qinghua; Cappelluti, Nico; Li, Yanxia

    2016-09-01

    We report the discovery of a remarkable concentration of massive galaxies with extended X-ray emission at z spec = 2.506, which contains 11 massive (M * ≳ 1011 M ⊙) galaxies in the central 80 kpc region (11.6σ overdensity). We have spectroscopically confirmed 17 member galaxies with 11 from CO and the remaining ones from Hα. The X-ray luminosity, stellar mass content, and velocity dispersion all point to a collapsed, cluster-sized dark matter halo with mass M 200c = 1013.9±0.2 M ⊙, making it the most distant X-ray-detected cluster known to date. Unlike other clusters discovered so far, this structure is dominated by star-forming galaxies (SFGs) in the core with only 2 out of the 11 massive galaxies classified as quiescent. The star formation rate (SFR) in the 80 kpc core reaches ∼3400 M ⊙ yr‑1 with a gas depletion time of ∼200 Myr, suggesting that we caught this cluster in rapid build-up of a dense core. The high SFR is driven by both a high abundance of SFGs and a higher starburst fraction (∼25%, compared to 3%–5% in the field). The presence of both a collapsed, cluster-sized halo and a predominant population of massive SFGs suggests that this structure could represent an important transition phase between protoclusters and mature clusters. It provides evidence that the main phase of massive galaxy passivization will take place after galaxies accrete onto the cluster, providing new insights into massive cluster formation at early epochs. The large integrated stellar mass at such high redshift challenges our understanding of massive cluster formation.

  5. Internal core tightener

    DOEpatents

    Brynsvold, Glen V.; Snyder, Jr., Harold J.

    1976-06-22

    An internal core tightener which is a linear actuated (vertical actuation motion) expanding device utilizing a minimum of moving parts to perform the lateral tightening function. The key features are: (1) large contact areas to transmit loads during reactor operation; (2) actuation cam surfaces loaded only during clamping and unclamping operation; (3) separation of the parts and internal operation involved in the holding function from those involved in the actuation function; and (4) preloaded pads with compliant travel at each face of the hexagonal assembly at the two clamping planes to accommodate thermal expansion and irradiation induced swelling. The latter feature enables use of a "fixed" outer core boundary, and thus eliminates the uncertainty in gross core dimensions, and potential for rapid core reactivity changes as a result of core dimensional change.

  6. Mars' core and magnetism.

    PubMed

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  7. Panelized wall system with foam core insulation

    DOEpatents

    Kosny, Jan; Gaskin, Sally

    2009-10-20

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  8. Dynamically scalable dual-core pipelined processor

    NASA Astrophysics Data System (ADS)

    Kumar, Nishant; Aggrawal, Ekta; Rajawat, Arvind

    2015-10-01

    This article proposes design and architecture of a dynamically scalable dual-core pipelined processor. Methodology of the design is the core fusion of two processors where two independent cores can dynamically morph into a larger processing unit, or they can be used as distinct processing elements to achieve high sequential performance and high parallel performance. Processor provides two execution modes. Mode1 is multiprogramming mode for execution of streams of instruction of lower data width, i.e., each core can perform 16-bit operations individually. Performance is improved in this mode due to the parallel execution of instructions in both the cores at the cost of area. In mode2, both the processing cores are coupled and behave like single, high data width processing unit, i.e., can perform 32-bit operation. Additional core-to-core communication is needed to realise this mode. The mode can switch dynamically; therefore, this processor can provide multifunction with single design. Design and verification of processor has been done successfully using Verilog on Xilinx 14.1 platform. The processor is verified in both simulation and synthesis with the help of test programs. This design aimed to be implemented on Xilinx Spartan 3E XC3S500E FPGA.

  9. Answering geological questions from slimhole coring exploration

    SciTech Connect

    Jantzen, R.E.; Syrstad, S.O.; Stockden, I.; Taylor, M. )

    1993-02-01

    Slimhole exploration wells have been proposed as a cost-efficient method of exploring inaccessible and remote areas. Such areas often have limited geological control, and the use of wire-line-retrieved, continuous coring methods adapted from the solid minerals industry can greatly improve the geological knowledge of a prospect or basin. However, there are geological concerns which may hinder the spread of slimhole exploration. The availability of core from long continuous sections of the well required a rethink of geological knowledge acquisition at the wellsite. Market analysis among explorationists confirmed the critical answers required from the core before it leaves the wellsite. These include the presence or absence of hydrocarbons, reservoirs, seals, source rock and maturity, lithologies and depositional environments. To provide answers, a conceptual core screening operation was developed around key variables which answer these geological questions. Throughput analyses, followed by time and motion studies, were performed to ensure wellsite suitability. A series of analysis systems have been built and assembled into a fit-for-purpose, heli-transportable wellsite core logging facility which has successfully completed a four well field trial in Africa. The purpose of this facility is to digitally preserve these key variables from the core through the use of a fully integrated data set encompassing mud, core and wireline logs, together with high-resolution digital images of the core. Data transmission from the wellsite to the project explorationists will ensure rapid answers from a cost-effective novel exploration method.

  10. 34. DESPATCH CORE OVENS, GREY IRON FOUNDRY CORE ROOM, BAKES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. DESPATCH CORE OVENS, GREY IRON FOUNDRY CORE ROOM, BAKES CORES THAT ARE NOT MADE ON HEATED OR COLD BOX CORE MACHINES, TO SET BINDING AGENTS MIXED WITH THE SAND CREATING CORES HARD ENOUGH TO WITHSTAND THE FLOW OF MOLTEN IRON INSIDE A MOLD. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  11. Multiple Core Galaxies

    NASA Technical Reports Server (NTRS)

    Miller, R.H.; Morrison, David (Technical Monitor)

    1994-01-01

    Nuclei of galaxies often show complicated density structures and perplexing kinematic signatures. In the past we have reported numerical experiments indicating a natural tendency for galaxies to show nuclei offset with respect to nearby isophotes and for the nucleus to have a radial velocity different from the galaxy's systemic velocity. Other experiments show normal mode oscillations in galaxies with large amplitudes. These oscillations do not damp appreciably over a Hubble time. The common thread running through all these is that galaxies often show evidence of ringing, bouncing, or sloshing around in unexpected ways, even though they have not been disturbed by any external event. Recent observational evidence shows yet another phenomenon indicating the dynamical complexity of central regions of galaxies: multiple cores (M31, Markarian 315 and 463 for example). These systems can hardly be static. We noted long-lived multiple core systems in galaxies in numerical experiments some years ago, and we have more recently followed up with a series of experiments on multiple core galaxies, starting with two cores. The relevant parameters are the energy in the orbiting clumps, their relative.masses, the (local) strength of the potential well representing the parent galaxy, and the number of cores. We have studied the dependence of the merger rates and the nature of the final merger product on these parameters. Individual cores survive much longer in stronger background potentials. Cores can survive for a substantial fraction of a Hubble time if they travel on reasonable orbits.

  12. New XMM-Newton observation of the Phoenix cluster: properties of the cool core

    NASA Astrophysics Data System (ADS)

    Tozzi, P.; Gastaldello, F.; Molendi, S.; Ettori, S.; Santos, J. S.; De Grandi, S.; Balestra, I.; Rosati, P.; Altieri, B.; Cresci, G.; Menanteau, F.; Valtchanov, I.

    2015-08-01

    Aims: We present a spectral analysis of a deep (220 ks) XMM-Newton observation of the Phoenix cluster (SPT-CL J2344-4243). We also use Chandra archival ACIS-I data that are useful for modeling the properties of the central bright active galactic nucleus and global intracluster medium. Methods: We extracted CCD and reflection grating spectrometer (RGS) X-ray spectra from the core region to search for the signature of cold gas and to finally constrain the mass deposition rate in the cooling flow that is thought to be responsible for the massive star formation episode observed in the brightest cluster galaxy (BCG). Results: We find an average mass-deposition rate of Ṁ = 620 (-190 + 200)stat (-50 + 150)syst M⊙ yr-1 in the temperature range 0.3-3.0 keV from MOS data. A temperature-resolved analysis shows that a significant amount of gas is deposited at about 1.8 keV and above, while only upper limits on the order of hundreds of M⊙ yr-1 can be placed in the 0.3-1.8 keV temperature range. From pn data we obtain Ṁ = 210 (-80 + 85)stat (-35 + 60)syst M⊙ yr-1 in the 0.3-3.0 keV temperature range, while the upper limits from the temperature-resolved analysis are typically a factor of 3 lower than MOS data. No line emission from ionization states below Fe XXIII is seen above 12 Å in the RGS spectrum, and the amount of gas cooling below ~3 keV has a formal best-fit value Ṁ = 122-122+343 M⊙ yr-1. In addition, our analysis of the far-infrared spectral energy distribution of the BCG based on Herschel data provides a star formation rate (SFR) equal to 530 M⊙ yr-1 with an uncertainty of 10%, which is lower than previous estimates by a factor 1.5. Overall, current limits on the mass deposition rate from MOS data are consistent with the SFR observed in the BCG, while pn data prefer a lower value of Ṁ ~ SFR/ 3, which is inconsistent with the SFR at the 3σ confidence level. Conclusions: Current data are able to firmly identify a substantial amount of cooling gas only

  13. Core shroud corner joints

    DOEpatents

    Gilmore, Charles B.; Forsyth, David R.

    2013-09-10

    A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

  14. Improvement of magnetic hysteresis loss, corrosion resistance and compressive strength through spark plasma sintering magnetocaloric LaFe11.65Si1.35/Cu core-shell powders

    NASA Astrophysics Data System (ADS)

    You, Caiyin; Wang, Shaopeng; Zhang, Jing; Yang, Nannan; Tian, Na

    2016-05-01

    LaFe11.65Si1.35/Cu core-shell powders were achieved by self-designed magnetron sputtering system, which presents a better solidification during spark plasma sintering in comparison to the naked LaFe11.65Si1.35 powders. Much higher compressive strength, lower corrosion current density and magnetic hysteresis losses are achieved for the sintered sample of LaFe11.65Si1.35/Cu core-shell powders without significant decrease of the magnetic entropy change. The compressive strength, corrosion current density and maximum magnetic hysteresis losses are 105.6 MPa/16.8 MPa, 1.08 × 10-3A/cm2/3.03 × 10-3 A/cm2 and 1.33 J/kg/2.71 J/kg, respectively for the sintered samples of core-shell structured/naked powders. The technique of fabricating the core-shell structured powders demonstrated here is also applicable for other types of functional powders.

  15. ARTEMISTM Core Simulator: Latest Developments

    NASA Astrophysics Data System (ADS)

    Hobson, Greg; Bolloni, Hans-Wilhelm; Breith, Karl-Albert; Dall'Osso, Aldo; van Geemert, René; Haase, Hartmut; Hartmann, Bettina; Leberig, Mario; Porsch, Dieter; Pothet, Baptiste; Riedmann, Michael; Sieber, Galina; Tomatis, Daniele

    2014-06-01

    AREVA has developed a new coupled neutronics/thermal-hydraulics code system, ARCADIA®. It makes use of modern computing resources to enable more realistic reactor analysis as improved understanding of nuclear reactor behavior is the basis for efficient margin management, i.e. optimization of safety and performance. One of the principal components of this new system is the core simulator, ARTEMIS™. The purpose of this paper is to recall its features, present the latest developments and give a summary of the validation tests.

  16. Contaminated Sediment Core Profiling

    EPA Science Inventory

    Evaluating the environmental risk of sites containing contaminated sediments often poses major challenges due in part to the absence of detailed information available for a given location. Sediment core profiling is often utilized during preliminary environmental investigations ...

  17. Midland Core Repository

    SciTech Connect

    Tyler, Noel

    2000-08-14

    This report summarizes activities for this quarter in one table. Industrial users of this repository viewed and/or checked out 163 boxes of drill cores and cuttings samples from 18 wells during the quarter.

  18. Core helium flash

    SciTech Connect

    Cole, P.W.; Deupree, R.G.

    1980-01-01

    The role of convection in the core helium flash is simulated by two-dimensional eddies interacting with the thermonuclear runaway. These eddies are followed by the explicit solution of the 2D conservation laws with a 2D finite difference hydrodynamics code. Thus, no phenomenological theory of convection such as the local mixing length theory is required. The core helium flash is violent, producing a deflagration wave. This differs from the detonation wave (and subsequent disruption of the entire star) produced in previous spherically symmetric violent core helium flashes as the second dimension provides a degree of relief which allows the expansion wave to decouple itself from the burning front. Our results predict that a considerable amount of helium in the core will be burned before the horizontal branch is reached and that some envelope mass loss is likely.

  19. Biospecimen Core Resource - TCGA

    Cancer.gov

    The Cancer Genome Atlas (TCGA) Biospecimen Core Resource centralized laboratory reviews and processes blood and tissue samples and their associated data using optimized standard operating procedures for the entire TCGA Research Network.

  20. Core assembly storage structure

    DOEpatents

    Jones, Jr., Charles E.; Brunings, Jay E.

    1988-01-01

    A structure for the storage of core assemblies from a liquid metal-cooled nuclear reactor. The structure comprises an enclosed housing having a substantially flat horizontal top plate, a bottom plate and substantially vertical wall members extending therebetween. A plurality of thimble members extend downwardly through the top plate. Each thimble member is closed at its bottom end and has an open end adjacent said top plate. Each thimble member has a length and diameter greater than that of the core assembly to be stored therein. The housing is provided with an inlet duct for the admission of cooling air and an exhaust duct for the discharge of air therefrom, such that when hot core assemblies are placed in the thimbles, the heat generated will by convection cause air to flow from the inlet duct around the thimbles and out the exhaust duct maintaining the core assemblies at a safe temperature without the necessity of auxiliary powered cooling equipment.

  1. Core Physics and Kinetics Calculations for the Fissioning Plasma Core Reactor

    NASA Technical Reports Server (NTRS)

    Butler, C.; Albright, D.

    2007-01-01

    Highly efficient, compact nuclear reactors would provide high specific impulse spacecraft propulsion. This analysis and numerical simulation effort has focused on the technical feasibility issues related to the nuclear design characteristics of a novel reactor design. The Fissioning Plasma Core Reactor (FPCR) is a shockwave-driven gaseous-core nuclear reactor, which uses Magneto Hydrodynamic effects to generate electric power to be used for propulsion. The nuclear design of the system depends on two major calculations: core physics calculations and kinetics calculations. Presently, core physics calculations have concentrated on the use of the MCNP4C code. However, initial results from other codes such as COMBINE/VENTURE and SCALE4a. are also shown. Several significant modifications were made to the ISR-developed QCALC1 kinetics analysis code. These modifications include testing the state of the core materials, an improvement to the calculation of the material properties of the core, the addition of an adiabatic core temperature model and improvement of the first order reactivity correction model. The accuracy of these modifications has been verified, and the accuracy of the point-core kinetics model used by the QCALC1 code has also been validated. Previously calculated kinetics results for the FPCR were described in the ISR report, "QCALC1: A code for FPCR Kinetics Model Feasibility Analysis" dated June 1, 2002.

  2. Micro coring apparatus

    NASA Technical Reports Server (NTRS)

    Collins, David; Brooks, Marshall; Chen, Paul; Dwelle, Paul; Fischer, Ben

    1989-01-01

    A micro-coring apparatus for lunar exploration applications, that is compatible with the other components of the Walking Mobile Platform, was designed. The primary purpose of core sampling is to gain an understanding of the geological composition and properties of the prescribed environment. This procedure has been used extensively for Earth studies and in limited applications during lunar explorations. The corer is described and analyzed for effectiveness.

  3. Nuclear core positioning system

    DOEpatents

    Garkisch, Hans D.; Yant, Howard W.; Patterson, John F.

    1979-01-01

    A structural support system for the core of a nuclear reactor which achieves relatively restricted clearances at operating conditions and yet allows sufficient clearance between fuel assemblies at refueling temperatures. Axially displaced spacer pads having variable between pad spacing and a temperature compensated radial restraint system are utilized to maintain clearances between the fuel elements. The core support plates are constructed of metals specially chosen such that differential thermal expansion produces positive restraint at operating temperatures.

  4. MCNP LWR Core Generator

    SciTech Connect

    Fischer, Noah A.

    2012-08-14

    The reactor core input generator allows for MCNP input files to be tailored to design specifications and generated in seconds. Full reactor models can now easily be created by specifying a small set of parameters and generating an MCNP input for a full reactor core. Axial zoning of the core will allow for density variation in the fuel and moderator, with pin-by-pin fidelity, so that BWR cores can more accurately be modeled. LWR core work in progress: (1) Reflectivity option for specifying 1/4, 1/2, or full core simulation; (2) Axial zoning for moderator densities that vary with height; (3) Generating multiple types of assemblies for different fuel enrichments; and (4) Parameters for specifying BWR box walls. Fuel pin work in progress: (1) Radial and azimuthal zoning for generating further unique materials in fuel rods; (2) Options for specifying different types of fuel for MOX or multiple burn assemblies; (3) Additional options for replacing fuel rods with burnable poison rods; and (4) Control rod/blade modeling.

  5. Emergency core cooling system

    DOEpatents

    Schenewerk, William E.; Glasgow, Lyle E.

    1983-01-01

    A liquid metal cooled fast breeder reactor provided with an emergency core cooling system includes a reactor vessel which contains a reactor core comprising an array of fuel assemblies and a plurality of blanket assemblies. The reactor core is immersed in a pool of liquid metal coolant. The reactor also includes a primary coolant system comprising a pump and conduits for circulating liquid metal coolant to the reactor core and through the fuel and blanket assemblies of the core. A converging-diverging venturi nozzle with an intermediate throat section is provided in between the assemblies and the pump. The intermediate throat section of the nozzle is provided with at least one opening which is in fluid communication with the pool of liquid sodium. In normal operation, coolant flows from the pump through the nozzle to the assemblies with very little fluid flowing through the opening in the throat. However, when the pump is not running, residual heat in the core causes fluid from the pool to flow through the opening in the throat of the nozzle and outwardly through the nozzle to the assemblies, thus providing a means of removing decay heat.

  6. Tuned Chamber Core Panel Acoustic Test Results

    NASA Technical Reports Server (NTRS)

    Schiller, Noah H.; Allen, Albert R.

    2016-01-01

    This report documents acoustic testing of tuned chamber core panels, which can be used to supplement the low-frequency performance of conventional acoustic treatment. The tuned chamber core concept incorporates low-frequency noise control directly within the primary structure and is applicable to sandwich constructions with a directional core, including corrugated-, truss-, and fluted-core designs. These types of sandwich structures have long, hollow channels (or chambers) in the core. By adding small holes through one of the facesheets, the hollow chambers can be utilized as an array of low-frequency acoustic resonators. These resonators can then be used to attenuate low-frequency noise (below 400 Hz) inside a vehicle compartment without increasing the weight or size of the structure. The results of this test program demonstrate that the tuned chamber core concept is effective when used in isolation or combined with acoustic foam treatments. Specifically, an array of acoustic resonators integrated within the core of the panels was shown to improve both the low-frequency absorption and transmission loss of the structure in targeted one-third octave bands.

  7. Core graduate courses: A missed learning opportunity?

    NASA Astrophysics Data System (ADS)

    Singh, Chandralekha; Maries, Alexandru

    2013-01-01

    An important goal of graduate physics core courses is to help students develop expertise in problem solving and improve their reasoning and meta-cognitive skills. We explore the conceptual difficulties of physics graduate students by administering conceptual problems on topics covered in undergraduate physics courses before and after instruction in related first year core graduate courses. Here, we focus on physics graduate students' difficulties manifested by their performance on two qualitative problems involving diagrammatic representation of vector fields. Some graduate students had great difficulty in recognizing whether the diagrams of the vector fields had divergence and/or curl but they had no difficulty computing the divergence and curl of the vector fields mathematically. We also conducted individual discussions with various faculty members who regularly teach first year graduate physics core courses about the goals of these courses and the performance of graduate students on the conceptual problems after related instruction in core courses.

  8. A scheme for lunar inner core detection

    NASA Astrophysics Data System (ADS)

    Williams, James G.

    2007-02-01

    Very precise measurements of the lunar gravity field could detect a solid inner core. For synchronous rotation, the equator planes of the inner core and mantle should be tilted with respect to the ecliptic plane and precess along that plane with the same 18.6 yr period. Generally, two different tilts would cause a static inner core gravity field to appear as small periodic (27.212 d) variations in the mantle-referenced C 21 and S 21 coefficients. Tidal variations also contribute to the C 21 variation so a much improved k 2 Love number would be required. Model computations suggest that the inner core signature is likely to be very small requiring sensitive gravity measurements. In principle, a signature analogous to the Moon's should be present for other synchronous satellites with interior liquid layers and also Mercury.

  9. Assessing Core Competencies

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2004-12-01

    Catherine Palomba and Trudy Banta offer the following definition of assessment, adapted from one provided by Marches in 1987. Assessment in the systematic collection, review, and use of information about educational programs undertaken for the purpose of improving student learning and development. (Palomba and Banta 1999). It is widely recognized that sophisticated computing technologies are becoming a key element in today's classroom instructional techniques. Regardless, the Professor must be held responsible for creating an instructional environment in which the technology actually supplements learning outcomes of the students. Almost all academic disciplines have found a niche for computer-based instruction in their respective professional domain. In many cases, it is viewed as an essential and integral part of the educational process. Educational institutions are committing substantial resources to the establishment of dedicated technology-based laboratories, so that they will be able to accommodate and fulfill students' desire to master certain of these specific skills. This type of technology-based instruction may raise some fundamental questions about the core competencies of the student learner. Some of the most important questions are : 1. Is the utilization of these fast high-powered computers and user-friendly software programs creating a totally non-challenging instructional environment for the student learner ? 2. Can technology itself all too easily overshadow the learning outcomes intended ? 3. Are the educational institutions simply training students how to use technology rather than educating them in the appropriate field ? 4. Are we still teaching content-driven courses and analysis oriented subject matter ? 5. Are these sophisticated modern era technologies contributing to a decline in the Critical Thinking Capabilities of the 21st century technology-savvy students ? The author tries to focus on technology as a tool and not on the technology

  10. Development of a core sheath process for production of oxide fibers

    NASA Technical Reports Server (NTRS)

    Freske, S.

    1972-01-01

    Improvements were sought in an oxide fiber of a core sheath configuration intended for structural applications at 2000 F (1093 C). Discontinuities in the core were eliminated by using core materials other than pure alumina, and continuous core sheath fibers were produced. In the case of some core materials, the continuous sections were sufficiently long for applications in short fiber composites. Creep at 2000 F (1093 C) was found to be due, in most cases, to breaks in the core, allowing the glass sheath to creep. Evidence was obtained indicating that a closer match between the thermal expansion coefficient of the sheath and the core would greatly improve the strength.

  11. Observations of Pre-Stellar Cores

    NASA Astrophysics Data System (ADS)

    Tafalla, M.

    2005-08-01

    Our understanding of the physical and chemical structure of pre-stellar cores, the simplest star-forming sites, has significantly improved since the last IAU Symposium on Astrochemistry (South Korea, 1999). Research done over these years has revealed that major molecular species like CO and CS systematically deplete onto dust grains in the interior of pre-stellar cores, while species like N2H+ and NH3 survive in the gas phase and can usually be detected toward the core centers. Such a selective behavior of molecular species gives rise to a differentiated (onion-like) chemical composition, and manifests itself in molecular maps as a dichotomy between centrally peaked and ring-shaped distributions. From the point of view of star-formation studies, the identification of molecular inhomogeneities in cores helps to resolve past discrepancies between observations made using different tracers, and brings the possibility of self-consistent modelling of the core internal structure. Here I present recent work on determining the physical and chemical structure of two pre-stellar cores, L1498 and L1517B, using observations in a large number of molecules and Monte Carlo radiative transfer analysis. These two cores are typical examples of the pre-stellar core population, and their chemical composition is characterized by the presence of large `freeze out holes' in most molecular species. In contrast with these chemically processed objects, a new population of chemically young cores has begun to emerge. The characteristics of its most extreme representative, L1521E, are briefly reviewed.

  12. Pressure Core Characterization

    NASA Astrophysics Data System (ADS)

    Santamarina, J. C.

    2014-12-01

    Natural gas hydrates form under high fluid pressure and low temperature, and are found in permafrost, deep lakes or ocean sediments. Hydrate dissociation by depressurization and/or heating is accompanied by a multifold hydrate volume expansion and host sediments with low permeability experience massive destructuration. Proper characterization requires coring, recovery, manipulation and testing under P-T conditions within the stability field. Pressure core technology allows for the reliable characterization of hydrate bearing sediments within the stability field in order to address scientific and engineering needs, including the measurement of parameters used in hydro-thermo-mechanical analyses, and the monitoring of hydrate dissociation under controlled pressure, temperature, effective stress and chemical conditions. Inherent sampling effects remain and need to be addressed in test protocols and data interpretation. Pressure core technology has been deployed to study hydrate bearing sediments at several locations around the world. In addition to pressure core testing, a comprehensive characterization program should include sediment analysis, testing of reconstituted specimens (with and without synthetic hydrate), and in situ testing. Pressure core characterization technology can be used to study other gas-charged formations such as deep sea sediments, coal bed methane and gas shales.

  13. Core Noise Reduction

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2011-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system-level noise metrics for the 2015, 2020, and 2025 timeframes; turbofan design trends and their aeroacoustic implications; the emerging importance of core noise and its relevance to the SFW Reduce-Perceived-Noise Technical Challenge; and the current research activities in the core noise area. Recent work1 on the turbine-transmission loss of combustor noise is briefly described, two2,3 new NRA efforts in the core-noise area are outlined, and an effort to develop CMC-based acoustic liners for broadband noise reduction suitable for turbofan-core application is delineated. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The reduction of aircraft noise is critical to enabling the anticipated large increase in future air traffic. The Subsonic Fixed Wing Project's Reduce-Perceived-Noise Technical Challenge aims to develop concepts and technologies to dramatically reduce the perceived aircraft noise outside of airport boundaries.

  14. A Critique of "The Common Core Is a Change for the Better"

    ERIC Educational Resources Information Center

    Wolfe, Adam

    2015-01-01

    In their article, "The Common Core is a Change for the Better," Gardner and Powell (2013) make an argument in support of implementing the Common Core to improve teaching and student learning. They opine the Common Core will enable students to become more college and career ready and state the Common Core standards will provide…

  15. Mars' Inner Core

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This figure shows a cross-section of the planet Mars revealing an inner, high density core buried deep within the interior. Dipole magnetic field lines are drawn in blue, showing the global scale magnetic field that one associates with dynamo generation in the core. Mars must have one day had such a field, but today it is not evident. Perhaps the energy source that powered the early dynamo has shut down. The differentiation of the planet interior - heavy elements like iron sinking towards the center of the planet - can provide energy as can the formation of a solid core from the liquid.

    The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. JPL is an operating division of California Institute of Technology (Caltech).

  16. Molten core retention assembly

    DOEpatents

    Lampe, Robert F.

    1976-06-22

    Molten fuel produced in a core overheating accident is caught by a molten core retention assembly consisting of a horizontal baffle plate having a plurality of openings therein, heat exchange tubes having flow holes near the top thereof mounted in the openings, and a cylindrical, imperforate baffle attached to the plate and surrounding the tubes. The baffle assembly is supported from the core support plate of the reactor by a plurality of hanger rods which are welded to radial beams passing under the baffle plate and intermittently welded thereto. Preferably the upper end of the cylindrical baffle terminates in an outwardly facing lip to which are welded a plurality of bearings having slots therein adapted to accept the hanger rods.

  17. CORE SATURATION BLOCKING OSCILLATOR

    DOEpatents

    Spinrad, R.J.

    1961-10-17

    A blocking oscillator which relies on core saturation regulation to control the output pulse width is described. In this arrangement an external magnetic loop is provided in which a saturable portion forms the core of a feedback transformer used with the thermionic or semi-conductor active element. A first stationary magnetic loop establishes a level of flux through the saturation portion of the loop. A second adjustable magnet moves the flux level to select a saturation point giving the desired output pulse width. (AEC)

  18. Finding the common core: evidence-based practices, clinically relevant evidence, and core mechanisms of change.

    PubMed

    Sexton, Thomas L; Kelley, Susan Douglas

    2010-03-01

    Improving the quality of children's mental health care can benefit from the adoption of evidence based and evidence informed treatments. However, the promise of moving science into practice is hampered by three core elements that need to be addressed in the current conversation among key stakeholders: (1) expanding our understanding of the clinical relevance of different types of evidence, (2) emphasizing the identification of core mechanisms of change, and (3) re-conceptualizing what evidence-based practice means. This paper focuses on these elements in an attempt to find a common core among stakeholders that may create opportunities for more inclusive conversation to move the field of children's mental health care forward.

  19. Lab-Scale Investigation of Multi-dimensional Relationships between Soil Intrinsic Properties to Improve Estimation of Soil Organic and Ice Content using Novel Core Imaging and Geophysical Techniques in Arctic Tundra

    NASA Astrophysics Data System (ADS)

    Ulrich, C.; Dafflon, B.; Wu, Y.; Kneafsey, T. J.; López, R. D.; Peterson, J.; Hubbard, S. S.

    2015-12-01

    Shallow permafrost distribution and characteristics are important for predicting ecosystem feedbacks to a changing climate over decadal to century timescales. These can drive active layer deepening and land surface deformation, which in turn can significantly affect hydrological and biogeochemical responses, including greenhouse gas dynamics. Investigating permafrost soil intrinsic properties generally involves time-consuming and expensive lab-based analysis of few soil cores over a large area and extrapolating between points to characterize spatial variations in soil properties. Geophysical techniques provide lower resolution data over a spatially large area and when coupled with high-resolution point data can potentially estimate with greater accuracy the spatial variation of investigated properties, thus limiting the difficulty of collecting many soil cores in remote areas. As part of the Next-Generation Ecosystem Experiment (NGEE-Arctic), we investigate multi-dimensional relationships between various permafrost intrinsic soil properties, and further linkages with geophysical parameters such as density from X-ray computed tomography (CT) and electrical conductivity from electrical resistance tomography (ERT) to evaluate how best to constrain estimation of properties as soil organic carbon content, ice content and saturation across low- to high-centered polygon features in the arctic tundra. Results of this study enable the quantification of the multi-dimensional relationships between intrinsic properties, which can be further used to constrain estimation of such properties from geophysical data and/or where limited core-based information is available. This study also enables the identification of the key controls on soil electrical resistivity and density at the investigated permafrost site, including salinity, porosity, water content, ice content, soil organic matter, and lithological properties. Overall, inferred multi-dimensional relationships and related

  20. Access to the Common Core for All

    ERIC Educational Resources Information Center

    McLaughlin, Margaret J.

    2012-01-01

    Too often under the various state-developed standards and assessments, accommodations for students with disabilities--a heterogeneous group with varied characteristics and needs--have not been adequately addressed or have been ignored. The Common Core State Standards (CCSS) initiative provides an historic opportunity to improve access to rigorous…

  1. Core Indicators of Effectiveness and Student Success.

    ERIC Educational Resources Information Center

    Muraski, Ed J.

    To help improve teaching and learning and to provide data required by the California community college system, Porterville College (PC) has assembled a list of core indicators of effectiveness and student success. This report describes PC's indicators and includes information on measurement criteria and data sources. First, definitions are…

  2. Planetary cores: a geodynamic perspective (Invited)

    NASA Astrophysics Data System (ADS)

    Nimmo, F.

    2010-12-01

    How can measurements of planetary core materials improve our understanding of their geodynamical behaviour? Here I will focus on three aspects of this questions: 1) core formation; 2) the growth and rheology of solid cores; 3) dynamo activity. Core formation occurs either due to the heat generated by short-lived nuclides (for small bodies) or due to gravitational energy released during impacts (for large bodies) [1]. Core formation results in elemental fractionation; such fractionation depends on P,T and oxygen fugacity [2], and for Earth-mass bodies occurs as a succession of discrete events. Experimental measurements of siderophile element partition coefficients are necessary to infer conditions during accretion, though these inferences are non-unique [3]. Core formation may also lead to isotopic fractionation of elements such as Si [4] and Fe [5], although the latter in particular is currently uncertain and merits further experimental investigation. Core solidification depends on the slopes of the adiabat and melting curve, and on the concentration and nature of the light element(s) present [6,7]. Solidification may proceed from outside in (for small bodies) or from inside out (for larger bodies); the solid may be either lighter or heavier than the fluid, depending on the core composition. Thus, core solidification is complex and poorly understood; for instance, Ganymede and Mercury’s cores may be in a completely different solidification regime to that of the Earth [8,9]. Solidification can also vary spatially, giving rise to inner core seismological structure [10,11]. The viscosity of a solid inner core is an important and poorly constrained parameter [12] which controls core deformation, core-mantle coupling and tidal heating. Super-Earths probably lack solid inner cores [13], though further high-P experimental data are needed. Core dynamos are usually thought to be driven by compositional or thermal buoyancy [14] , with the former effect dominant for small

  3. Photon upconversion in core-shell nanoparticles.

    PubMed

    Chen, Xian; Peng, Denfeng; Ju, Qiang; Wang, Feng

    2015-03-21

    Photon upconversion generally results from a series of successive electronic transitions within complex energy levels of lanthanide ions that are embedded in the lattice of a crystalline solid. In conventional lanthanide-doped upconversion nanoparticles, the dopant ions homogeneously distributed in the host lattice are readily accessible to surface quenchers and lose their excitation energy, giving rise to weak and susceptible emissions. Therefore, present studies on upconversion are mainly focused on core-shell nanoparticles comprising spatially confined dopant ions. By doping upconverting lanthanide ions in the interior of a core-shell nanoparticle, the upconversion emission can be substantially enhanced, and the optical integrity of the nanoparticles can be largely preserved. Optically active shells are also frequently employed to impart multiple functionalities to upconversion nanoparticles. Intriguingly, the core-shell design introduces the possibility of constructing novel upconversion nanoparticles by exploiting the energy exchange interactions across the core-shell interface. In this tutorial review, we highlight recent advances in the development of upconversion core-shell nanoparticles, with particular emphasis on the emerging strategies for regulating the interplay of dopant interactions through core-shell nanostructural engineering that leads to unprecedented upconversion properties. The improved control over photon energy conversion will open up new opportunities for biological and energy applications. PMID:25058157

  4. ACGME core competencies: where are we?

    PubMed

    Yaszay, Burt; Kubiak, Erik; Agel, Julie; Hanel, Douglas P

    2009-03-01

    Beginning in July 2002, the Accreditation Council for Graduate Medical Education (ACGME) instructed all residency programs to require their residents to demonstrate competency in 6 core areas: patient care, interpersonal and communication skills, medical knowledge, professionalism, practice-based learning, and systems-based practice. The goal was to have objective markers of performance that would serve as a gauge to determine a program's accreditation. To determine the experiences of orthopedic residency programs with regard to the ACGME's core competencies, a national survey was administered to orthopedic program directors and selected orthopedic residents. Of those orthopedic programs that responded, most appeared to be complying with the ACGME requirements. Both directors and residents thought patient care and medical knowledge ranked most important, while practice-based learning and systems-based practice were assigned the lowest ranks. Barriers to implementation of the core competencies included low priority compared with clinical duties, lack of faculty or resident education, and lack of formal orthopedic core competencies. Residents and program directors agreed that their programs would benefit from a definition of each of the core competencies, including a greater commitment to the processes involved in surgical procedures. This study demonstrated a commitment to the core competencies by the programs that responded. The survey also suggested this commitment would be aided by improved definitions of some of the competencies for the orthopedic resident.

  5. Massive Magnetic Core

    NASA Technical Reports Server (NTRS)

    1964-01-01

    The massive magnetic core of the Space Radiation Effects Laboratory's Synchrocyclotron at NASA's Langley Research Center. The 3000 ton (6 million pound), 36' x 21'x 19.5' assembly of forged steel serves as the heart of the 600 million electron volt, high energy proton accelerator.

  6. Looking for Core Values

    ERIC Educational Resources Information Center

    Carter, Margie

    2010-01-01

    People who view themselves as leaders, not just managers or teachers, are innovators who focus on clarifying core values and aligning all aspects of the organization with these values to grow their vision. A vision for an organization can't be just one person's idea. Visions grow by involving people in activities that help them name and create…

  7. Ultrasonic Drilling and Coring

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph

    1998-01-01

    A novel drilling and coring device, driven by a combination, of sonic and ultrasonic vibration, was developed. The device is applicable to soft and hard objects using low axial load and potentially operational under extreme conditions. The device has numerous potential planetary applications. Significant potential for commercialization in construction, demining, drilling and medical technologies.

  8. The Uncommon Core

    ERIC Educational Resources Information Center

    Ohler, Jason

    2013-01-01

    This author contends that the United States neglects creativity in its education system. To see this, he states, one may look at the Common Core State Standards. If one searches the English Language Arts and Literacy standards for the words "creative," "innovative," and "original"--and any associated terms, one will find scant mention of the words…

  9. Some Core Contested Concepts

    ERIC Educational Resources Information Center

    Chomsky, Noam

    2015-01-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and…

  10. Core Directions in HRD.

    ERIC Educational Resources Information Center

    1996

    This document consists of four papers presented at a symposium on core directions in human resource development (HRD) moderated by Verna Willis at the 1996 conference of the Academy of Human Resource Development. "Reengineering the Organizational HRD Function: Two Case Studies" (Neal Chalofsky) reports an action research study in which the…

  11. University City Core Plan.

    ERIC Educational Resources Information Center

    Philadelphia City Planning Commission, PA.

    A redevelopment plan for an urban core area of about 300 acres was warranted by--(1) unsuitable building conditions, (2) undesirable land usage, and (3) faulty traffic circulation. The plan includes expansion of two universities and creation of a regional science center, high school, and medical center. Guidelines for proposed land use and zoning…

  12. Languages for Dublin Core.

    ERIC Educational Resources Information Center

    Baker, Thomas

    1998-01-01

    Focusing on languages for the Dublin Core, examines the experience of some related ways to seek semantic interoperability through simplicity: planned languages, interlingua constructs, and pidgins. Also defines the conceptual and organizational problem of maintaining a metadata standard in multiple languages. (AEF)

  13. Navagating the Common Core

    ERIC Educational Resources Information Center

    McShane, Michael Q.

    2014-01-01

    This article presents a debate over the Common Core State Standards Initiative as it has rocketed to the forefront of education policy discussions around the country. The author contends that there is value in having clear cross state standards that will clarify the new online and blended learning that the growing use of technology has provided…

  14. Electromagnetic pump stator core

    DOEpatents

    Fanning, Alan W.; Olich, Eugene E.; Dahl, Leslie R.

    1995-01-01

    A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter.

  15. From Context to Core

    ERIC Educational Resources Information Center

    Campus Technology, 2008

    2008-01-01

    At Campus Technology 2008, Arizona State University Technology Officer Adrian Sannier mesmerized audiences with his mandate to become more efficient by doing only the "core" tech stuff--and getting someone else to slog through the context. This article presents an excerpt from Sannier's hour-long keynote address at Campus Technology '08. Sannier…

  16. Theory of core excitons

    SciTech Connect

    Dow, J. D.; Hjalmarson, H. P.; Sankey, O. F.; Allen, R. E.; Buettner, H.

    1980-01-01

    The observation of core excitons with binding energies much larger than those of the valence excitons in the same material has posed a long-standing theoretical problem. A proposed solution to this problem is presented, and Frenkel excitons and Wannier excitons are shown to coexist naturally in a single material. (GHT)

  17. Resolving Supercritical Orion Cores

    NASA Astrophysics Data System (ADS)

    Li, Di; Chapman, N.; Goldsmith, P.; Velusamy, T.

    2009-01-01

    The theoretical framework for high mass star formation (HMSF) is unclear. Observations reveal a seeming dichotomy between high- and low-mass star formation, with HMSF occurring only in Giant Molecular Clouds (GMC), mostly in clusters, and with higher star formation efficiencies than low-mass star formation. One crucial constraint to any theoretical model is the dynamical state of massive cores, in particular, whether a massive core is in supercritical collapse. Based on the mass-size relation of dust emission, we select likely unstable targets from a sample of massive cores (Li et al. 2007 ApJ 655, 351) in the nearest GMC, Orion. We have obtained N2H+ (1-0) maps using CARMA with resolution ( 2.5", 0.006 pc) significantly better than existing observations. We present observational and modeling results for ORI22. By revealing the dynamic structure down to Jeans scale, CARMA data confirms the dominance of gravity over turbulence in this cores. This work was performed by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  18. Why a Core?

    ERIC Educational Resources Information Center

    Murphy, James Bernard

    2006-01-01

    Sadly, amidst a vast profusion of knowledge, universities abrogate responsibility for showing young learners what is essential. Left to select for themselves, most students arrive late, if at all, to an awareness of what they want and need out of college. Thus, according to James Bernard Murphy, a well-constructed core of courses, presented in the…

  19. The Earth's Core.

    ERIC Educational Resources Information Center

    Jeanloz, Raymond

    1983-01-01

    The nature of the earth's core is described. Indirect evidence (such as that determined from seismological data) indicates that it is an iron alloy, solid toward its center but otherwise liquid. Evidence also suggests that it is the turbulent flow of the liquid that generates the earth's magnetic field. (JN)

  20. A World Core Curriculum.

    ERIC Educational Resources Information Center

    Muller, Robert

    1993-01-01

    Robert Muller's "World Core Curriculum" is designed to give children: a good picture of planet Earth and the universe; a correct picture of the commonalities and diversity of the human family; an accurate picture of the time period into which they are born; and a sense of their own importance and the role that they can play in society. (MDM)

  1. VLT-SINFONI sub-kpc study of the star formation in local LIRGs and ULIRGs. Analysis of the global ΣSFR structure and characterisation of individual star-forming clumps

    NASA Astrophysics Data System (ADS)

    Piqueras López, J.; Colina, L.; Arribas, S.; Pereira-Santaella, M.; Alonso-Herrero, A.

    2016-05-01

    We present a two-dimensional study of star formation at kiloparsec and sub-kiloparsec scales of a sample of local (z < 0.1) luminous (10) and ultraluminous (7) infrared galaxies (U/LIRGs), based on near-infrared VLT-SINFONI integral field spectroscopy (IFS). We obtained integrated measurements of the star formation rate and star formation rate surface density, together with their 2D distributions, based on Brγ and Paα emission. In agreement with previous studies, we observe a tight linear correlation between the star formation rate (SFR) derived from our extinction-corrected Paα measurements and that derived from Spitzer 24 μm data, and a reasonable agreement with SFR derived from LIR. We also compared our SFRPaα values with optical measurements from Hα emission and find that the SFRPaα is on average a factor ~3 larger than the SFRHα, even when the extinction corrections are applied. Within the angular resolution and sizes sampled by the SINFONI observations, we found that LIRGs have a median-observed star formation rate surface density of ΣLIRGsobs=1.16 M⊙ yr-1 kpc-2, and ΣLIRGscorr=1.72 M⊙ yr-1 kpc-2 for the extinction-corrected distribution. The median-observed and the extinction-corrected ΣSFR values for ULIRGs are ΣULIRGsobs=0.16 M⊙ yr-1 kpc-2 and ΣULIRGscorr=0.23 M⊙ yr-1 kpc-2, respectively. These median values for ULIRGs increase up to 1.38 M⊙ yr-1 kpc-2 and 2.90 M⊙ yr-1 kpc-2, when only their inner regions, covering the same size as the average FoV of LIRGs, are considered. For a given fixed angular sampling, our simulations show that the predicted median of the ΣSFR distribution increases artificially with distance, a factor ~2-3 when the original measurements for LIRGs are simulated at the average distance of our ULIRGs. This could have consequences on any estimates of the star formation surface brightness in high-z galaxies, and consequently on the derivation of the universality of star formation laws at all redshifts. We

  2. Lunar Polar Coring Lander

    NASA Technical Reports Server (NTRS)

    Angell, David; Bealmear, David; Benarroche, Patrice; Henry, Alan; Hudson, Raymond; Rivellini, Tommaso; Tolmachoff, Alex

    1990-01-01

    Plans to build a lunar base are presently being studied with a number of considerations. One of the most important considerations is qualifying the presence of water on the Moon. The existence of water on the Moon implies that future lunar settlements may be able to use this resource to produce things such as drinking water and rocket fuel. Due to the very high cost of transporting these materials to the Moon, in situ production could save billions of dollars in operating costs of the lunar base. Scientists have suggested that the polar regions of the Moon may contain some amounts of water ice in the regolith. Six possible mission scenarios are suggested which would allow lunar polar soil samples to be collected for analysis. The options presented are: remote sensing satellite, two unmanned robotic lunar coring missions (one is a sample return and one is a data return only), two combined manned and robotic polar coring missions, and one fully manned core retrieval mission. One of the combined manned and robotic missions has been singled out for detailed analysis. This mission proposes sending at least three unmanned robotic landers to the lunar pole to take core samples as deep as 15 meters. Upon successful completion of the coring operations, a manned mission would be sent to retrieve the samples and perform extensive experiments of the polar region. Man's first step in returning to the Moon is recommended to investigate the issue of lunar polar water. The potential benefits of lunar water more than warrant sending either astronauts, robots or both to the Moon before any permanent facility is constructed.

  3. The Moon's Molten Core and Tidal Q

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.; Dickey, J. O.

    1998-01-01

    The rotation of the Moon is influenced by solid-body tides and interaction at a liquid-core/solid-mantle boundary. The Lunar Laser Ranging (LLR) data are sensitive to variations in lunar rotation. Analysis of those ranges reveals four dissipation periodicities in the rotation. These signatures can be explained with the combined effects of tide plus core, but not with either alone. The fluid core detection exceeds three times its uncertainty. The inferred core radius has a 1 -sigma upper limit of 352 km for iron and up to 374 km if sulfur is present. The tidal dissipation is strong, Q at one month is 37 +/- 5 .Q increases for longer periods and is 60 (-15, +40) at one year.Dynamical evidence for a fluid lunar core has previously been presented. These-earlier solutions included three dissipation parameters. New solutions benefit from additional LLR data and an improved gravity field from Doppler tracking of Lunar Prospector. Five dissipation parameters are now solved for. There are several options for dissipation parameters: a core coupling parameter, a time delay for tidal distortion of the moments of inertia, and five periodic terms in the rotation angles. Solutions with different combinations of these are compatible (a theory relates K/C and time delay to a series of periodic terms). The solutions used K/C, time delay, and one periodic term. When dissipation signatures at five rotation frequencies are solved for, four amplitudes (4 to 263 milliarcseconds) are detected above the noise. Attempts to explain these results using either tides alone or core alone fail (less than 3(sigma) discrepancy for the former and 9(sigma), for the latter). A combination of tides and liquid core matches the results well.

  4. The core legion object model

    SciTech Connect

    Lewis, M.; Grimshaw, A.

    1996-12-31

    The Legion project at the University of Virginia is an architecture for designing and building system services that provide the illusion of a single virtual machine to users, a virtual machine that provides secure shared object and shared name spaces, application adjustable fault-tolerance, improved response time, and greater throughput. Legion targets wide area assemblies of workstations, supercomputers, and parallel supercomputers, Legion tackles problems not solved by existing workstation based parallel processing tools; the system will enable fault-tolerance, wide area parallel processing, inter-operability, heterogeneity, a single global name space, protection, security, efficient scheduling, and comprehensive resource management. This paper describes the core Legion object model, which specifies the composition and functionality of Legion`s core objects-those objects that cooperate to create, locate, manage, and remove objects in the Legion system. The object model facilitates a flexible extensible implementation, provides a single global name space, grants site autonomy to participating organizations, and scales to millions of sites and trillions of objects.

  5. Improvement on controllable fabrication of streptavidin-modified three-layer core-shell Fe3O4@SiO2@Au magnetic nanocomposites with low fluorescence background.

    PubMed

    Jiang, Hongrong; Zeng, Xin; Xi, Zhijiang; Liu, Ming; Li, Chuanyan; Li, Zhiyang; Jin, Lian; Wang, Zhifei; Deng, Yan; He, Nongyue

    2013-04-01

    In present study, we put forward an approach to prepare three-layer core-shell Fe3O4@SiO2@Au magnetic nanocomposites via the combination of self-assembling, seed-mediated growing and multi-step chemical reduction. The Fe3O4@SiO2@Au magnetic nanocomposites were analyzed and characterized by transmission electron microscope (TEM), scanning electronic microscope (SEM), energy dispersive spectrometer analysis (EDS), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), and ultraviolet and visible spectrophotometer (UV-Vis). TEM and SEM characterizations showed that the FeO4@SiO2@Au nanocomposites were obtained successfully with three-layer structures, especially a layer of thin, smooth and continuous gold shell. The average diameter of Fe3O4@SiO2@Au nanocomposites was about 600 nm and an excellent dispersity was observed for the as-prepared nanoparticles. EDS characterizations demonstrated that the nanocomposites contained three elements of the precursors, Fe, Si, and Au. Furthermore, FT-IR showed that the silica and gold shell were coated successfully. UV-Vis and VSM characterizations showed that the Fe3O4@SiO2@Au nanocomposites exhibited good optical and magnetic property, and the saturation magnetization was 25.76 emu/g. In conclusion, the Fe3O4@SiO2@Au magnetic nanocomposites with three-layer core-shell structures were prepared. Furthermore, Fe3O4@SiO2@Au magnetic nanocomposites were modified with streptavidin (SA) successfully, and it was validated that they performed low fluorescence background, suggesting that they should have good applications especially in bioassay based on fluorescence detection through bonding the biotinylated fluorescent probes. PMID:23621028

  6. Application of Core Dynamics Modeling to Core-Mantle Interactions

    NASA Technical Reports Server (NTRS)

    Kuang, Weijia

    2003-01-01

    Observations have demonstrated that length of day (LOD) variation on decadal time scales results from exchange of axial angular momentum between the solid mantle and the core. There are in general four core-mantle interaction mechanisms that couple the core and the mantle. Of which, three have been suggested likely the dominant coupling mechanism for the decadal core-mantle angular momentum exchange, namely, gravitational core-mantle coupling arising from density anomalies in the mantle and in the core (including the inner core), the electromagnetic coupling arising from Lorentz force in the electrically conducting lower mantle (e.g. D-layer), and the topographic coupling arising from non-hydrostatic pressure acting on the core-mantle boundary (CMB) topography. In the past decades, most effort has been on estimating the coupling torques from surface geomagnetic observations (kinematic approach), which has provided insights on the core dynamical processes. In the meantime, it also creates questions and concerns on approximations in the studies that may invalidate the corresponding conclusions. The most serious problem is perhaps the approximations that are inconsistent with dynamical processes in the core, such as inconsistencies between the core surface flow beneath the CMB and the CMB topography, and that between the D-layer electric conductivity and the approximations on toroidal field at the CMB. These inconsistencies can only be addressed with numerical core dynamics modeling. In the past few years, we applied our MoSST (Modular, Scalable, Self-consistent and Three-dimensional) core dynamics model to study core-mantle interactions together with geodynamo simulation, aiming at assessing the effect of the dynamical inconsistencies in the kinematic studies on core-mantle coupling torques. We focus on topographic and electromagnetic core-mantle couplings and find that, for the topographic coupling, the consistency between the core flow and the CMB topography is

  7. First Core and Refueling Options for IRIS

    SciTech Connect

    Petrovic, Bojan; Carelli, Mario D.; Greenspan, Ehud; Milosevic, Miodrag; Vujic, Jasmina; Padovani, Enrico; Ganda, Francesco

    2002-07-01

    The International Reactor Innovative and Secure (IRIS) is being developed by an international consortium of industry, laboratory, university and utility establishments, led by Westinghouse. The IRIS design addresses key requirements associated with advanced reactors, including improved safety, enhanced proliferation resistance, competitive electricity production cost, and improved waste management. IRIS is a modular, small/medium size (100 to 335 MWe) PWR with integral vessel configuration. Its design is based on proven LWR technology, so that no new technology development is needed and near term deployment is possible. At the same time, aim was to introduce improvements as compared to present PWRs. These opposing requirements resulted in an evolutionary approach to fuel and core design, balancing new features and the need to avoid extensive testing and demonstration programs. A path forward was devised by selecting the current fuel technology for the first IRIS core, but keeping future upgrades possible through the variable moderation fuel assembly design. This paper describes this approach and discusses core fueling options that enable achieving four-year and eight-year core lifetime. (authors)

  8. The Common Core Is a Change for the Better

    ERIC Educational Resources Information Center

    Gardner, Nancy S.; Powell, Rod

    2014-01-01

    The authors, two high school teachers, endorse the Common Core State Standards saying they will improve teaching and learning. The Common Core, they say, not only help students acquire the skills for success in life after high school, but they offer consistency in a student's educational journey and let employers know what to expect.…

  9. How Should the Graduate Economics Core Be Changed?

    ERIC Educational Resources Information Center

    Abito, Jose Miguel; Borovickova, Katarina; Golden, Hays; Goldin, Jacob; Masten, Matthew A.; Morin, Miguel; Poirier, Alexandre; Pons, Vincent; Romem, Israel; Williams, Tyler; Yoon, Chamna

    2011-01-01

    The authors present suggestions by graduate students from a range of economics departments for improving the first-year core sequence in economics. The students identified a number of elements that should be added to the core: more training in building microeconomic models, a discussion of the methodological foundations of model-building, more…

  10. Dynamics of core accretion

    NASA Astrophysics Data System (ADS)

    Nelson, Andrew F.; Ruffert, Maximilian

    2013-02-01

    We perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass Mpl = 10M⊕ embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the `Piecewise Parabolic Method' with as many as six fixed nested grids, providing spatial resolution on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either `locally isothermal' or `locally isentropic') and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling however, as defined by locally isothermal or

  11. Long Valley Coring Project

    USGS Publications Warehouse

    Sass, John; Finger, John; McConnel, Vicki

    1998-01-01

    In December 1997, the California Energy Commission (CEC) agreed to provide funding for Phase III continued drilling of the Long Valley Exploratory Well (LVEW) near Mammoth Lakes, CA, from its present depth. The CEC contribution of $1 million completes a funding package of $2 million from a variety of sources, which will allow the well to be cored continuously to a depth of between 11,500 and 12,500 feet. The core recovered from Phase III will be crucial to understanding the origin and history of the hydrothermal systems responsible for the filling of fractures in the basement rock. The borehole may penetrate the metamorphic roof of the large magmatic complex that has fed the volcanism responsible for the caldera and subsequent activity.

  12. Core Outlet Temperature Study

    SciTech Connect

    Moisseytsev, A.; Hoffman, E.; Majumdar, S.

    2008-07-28

    It is a known fact that the power conversion plant efficiency increases with elevation of the heat addition temperature. The higher efficiency means better utilization of the available resources such that higher output in terms of electricity production can be achieved for the same size and power of the reactor core or, alternatively, a lower power core could be used to produce the same electrical output. Since any nuclear power plant, such as the Advanced Burner Reactor, is ultimately built to produce electricity, a higher electrical output is always desirable. However, the benefits of the higher efficiency and electricity production usually come at a price. Both the benefits and the disadvantages of higher reactor outlet temperatures are analyzed in this work.

  13. Dynamics of core accretion

    DOE PAGES

    Nelson, Andrew F.; Ruffert, Maximilian

    2012-12-21

    In this paper, we perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass Mpl = 10M⊕ embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the ‘Piecewise Parabolic Method’ with as many as six fixed nested grids, providing spatial resolutionmore » on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either ‘locally isothermal’ or ‘locally isentropic’) and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling however, as

  14. Dynamics of core accretion

    SciTech Connect

    Nelson, Andrew F.; Ruffert, Maximilian

    2012-12-21

    In this paper, we perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass Mpl = 10M embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the ‘Piecewise Parabolic Method’ with as many as six fixed nested grids, providing spatial resolution on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either ‘locally isothermal’ or ‘locally isentropic’) and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling

  15. Critical CRBR core pressure

    SciTech Connect

    Ju, F.D.

    1980-06-01

    The conditions are detailed under which gas pressure will cause or initiate failure in the structural containment of the fuel core. The Clinch River Breeder Reactor Plant is the prototype structure. Two general classes of problems have been studied, representing two entirely distinct configurations of containment failure. The first model determines the minimum pressure to lift a portion or the entire core from its containment. The second model estimates the critical pressure above which the fuel rods interior to the hexagonal fuel can warp, leading to blockage of the gas passages. Such blockage might cause further buildup of the gas pressure to a level causing the failure of the fuel rod containment in the hexagonal fuel container.

  16. Some core contested concepts.

    PubMed

    Chomsky, Noam

    2015-02-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and to lead to conclusions about a number of significant issues that differ from some conventional beliefs.

  17. Banded electromagnetic stator core

    DOEpatents

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1996-06-11

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

  18. Banded electromagnetic stator core

    DOEpatents

    Fanning, Alan W.; Gonzales, Aaron A.; Patel, Mahadeo R.; Olich, Eugene E.

    1994-01-01

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

  19. Banded electromagnetic stator core

    DOEpatents

    Fanning, Alan W.; Gonzales, Aaron A.; Patel, Mahadeo R.; Olich, Eugene E.

    1996-01-01

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

  20. Banded electromagnetic stator core

    DOEpatents

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1994-04-05

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

  1. Variable depth core sampler

    DOEpatents

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  2. Variable depth core sampler

    DOEpatents

    Bourgeois, Peter M.; Reger, Robert J.

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  3. Cross Cell Sandwich Core

    NASA Technical Reports Server (NTRS)

    Ford, Donald B. (Inventor)

    2004-01-01

    A sandwich core comprises two faceplates separated by a plurality of cells. The cells are comprised of walls positioned at oblique angles relative to a perpendicular axis extending through the faceplates. The walls preferably form open cells and are constructed from open cells and are constructed from rows of ribbons. The walls may be obliquely angled relative to more than one plane extending through the perpendicular axis.

  4. Toroidal core winder

    DOEpatents

    Potthoff, Clifford M.

    1978-01-01

    The disclosure is directed to an apparatus for placing wire windings on a toroidal body, such as a transformer core, having an orifice in its center. The apparatus comprises a wire storage spool, a wire loop holding continuous belt maintained in a C-shaped loop by a belt supporting structure and provision for turning the belt to place and tighten loops of wire on a toroidal body, which is disposed within the gap of the C-shaped belt loop.

  5. Electromagnetic pump stator core

    DOEpatents

    Fanning, A.W.; Olich, E.E.; Dahl, L.R.

    1995-01-17

    A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter. 21 figures.

  6. Fissioning Plasma Core Reactor

    NASA Technical Reports Server (NTRS)

    Albright, Dennis; Butler, Carey; West, Nicole; Cole, John W. (Technical Monitor)

    2002-01-01

    Institute for Scientific Research, Inc. (ISR) research program consist of: 1.Study core physics by adapting existing codes: MCNP4C - Monte Carlo code; COMBINE/VENTURE - diffusion theory; SCALE4 - Monte Carlo, with many utility codes. 2. Determine feasibility and study major design parameters: fuel selection, temperature and reflector sizing. 3. Study reactor kinetics: develop QCALC1 to model point kinetics; study dynamic behavior of the power release.

  7. Planetary cores: current knowledge and future prospects

    NASA Astrophysics Data System (ADS)

    Nimmo, F.

    2011-12-01

    provide similar constraints. For some exoplanets, specific orbital configurations provide constraints on the interior structure [17]. Future Prospects. GRAIL and MESSENGER will soon improve our understanding of the lunar and Mercurian cores, while Dawn may detect evidence of that body's presumed core. Modelling the spin evolution and coupling of bodies containing liquid layers represents a major theoretical challenge, and provides a link between geodetic observations and both core structure and dynamo generation. [1] Kleine et al., GCA 73, 5150, 2009. [2] Moynier et al., Science 331, 1417-20, 2011. [3] Georg et al., Nature 447, 1102-06, 2007. [4] Dauphas and Pourmand, Nature 473, 489, 2011. [5] Rubie et al., Treat. Geophys. 9, 51-90, 2007. [6] Agnor et al., Nature 439, 155, 2006. [7] Benz et al., Space Sci. Rev. 132, 189, 2007. [8] Weber et al., Science 331, 309-11, 2011. [9] Solomon, Icarus 28, 509, 1976. [10] Nimmo, Treat. Geophys. 9, 217-242, 2007. [11] Dwyer et al., LPSC 42, 2044, 2011. [12] Le Bars et al., LPSC 42, 2291, 2011. [13] Williams et al., JGR 106, 27933, 2001. [14] Margot et al., Science 316, 710, 2007. [15] Folkner et al., Science 278, 1749-52, 1997. [16] Buffett, Nature 468, 952, 2010. [17] Batygin et al., Ap.J.L. 704, 49-53, 2009.

  8. Efficiency of static core turn-off in a system-on-a-chip with variation

    DOEpatents

    Cher, Chen-Yong; Coteus, Paul W; Gara, Alan; Kursun, Eren; Paulsen, David P; Schuelke, Brian A; Sheets, II, John E; Tian, Shurong

    2013-10-29

    A processor-implemented method for improving efficiency of a static core turn-off in a multi-core processor with variation, the method comprising: conducting via a simulation a turn-off analysis of the multi-core processor at the multi-core processor's design stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's design stage includes a first output corresponding to a first multi-core processor core to turn off; conducting a turn-off analysis of the multi-core processor at the multi-core processor's testing stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's testing stage includes a second output corresponding to a second multi-core processor core to turn off; comparing the first output and the second output to determine if the first output is referring to the same core to turn off as the second output; outputting a third output corresponding to the first multi-core processor core if the first output and the second output are both referring to the same core to turn off.

  9. GEOS-CORE

    SciTech Connect

    2014-06-24

    GEOS-CORE is a code that integrates open source Libraries for linear algebra and I/O with two main LLNL-written components: (i) a set of standard finite, discrete, and discontinuous displacement element physics solvers for resolving Darcy fluid flow, explicit mechanics, implicit mechanics, and fluid-mediated fracturing, including resolution of physical behaviors both implicitly and explicitly, and (ii) a MPI-based parallelization implementation for use on generic HPC distributed memory architectures. The resultant code can be used alone for linearly elastic and quasistatic damage problems; problems involving hydraulic fracturing, where the mesh topology is dynamically changed; and general granular materials behavior. The key application domain is for low-rate stimulation and fracture control in subsurface reservoirs (e.g., enhanced geothermal sites and unconventional shale gas stimulation). GEOS-CORE also has interfaces to call external libraries for, e.g., material models and equations fo state; however, LLNL-developed EOS and material models, beyond the aforementioned linear elastic and quasi-static damage models, will not be part of the current release. GEOS-CORE's secondary applications include granular materials behavior under different load paths.

  10. GEOS-CORE

    2014-06-24

    GEOS-CORE is a code that integrates open source Libraries for linear algebra and I/O with two main LLNL-written components: (i) a set of standard finite, discrete, and discontinuous displacement element physics solvers for resolving Darcy fluid flow, explicit mechanics, implicit mechanics, and fluid-mediated fracturing, including resolution of physical behaviors both implicitly and explicitly, and (ii) a MPI-based parallelization implementation for use on generic HPC distributed memory architectures. The resultant code can be used alone formore » linearly elastic and quasistatic damage problems; problems involving hydraulic fracturing, where the mesh topology is dynamically changed; and general granular materials behavior. The key application domain is for low-rate stimulation and fracture control in subsurface reservoirs (e.g., enhanced geothermal sites and unconventional shale gas stimulation). GEOS-CORE also has interfaces to call external libraries for, e.g., material models and equations fo state; however, LLNL-developed EOS and material models, beyond the aforementioned linear elastic and quasi-static damage models, will not be part of the current release. GEOS-CORE's secondary applications include granular materials behavior under different load paths.« less

  11. 33. BENCH CORE STATION, GREY IRON FOUNDRY CORE ROOM WHERE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. BENCH CORE STATION, GREY IRON FOUNDRY CORE ROOM WHERE CORE MOLDS WERE HAND FILLED AND OFTEN PNEUMATICALLY COMPRESSED WITH A HAND-HELD RAMMER BEFORE THEY WERE BAKED. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  12. NEUTRONIC REACTOR FUEL ELEMENT AND CORE SYSTEM

    DOEpatents

    Moore, W.T.

    1958-09-01

    This patent relates to neutronic reactors and in particular to an improved fuel element and a novel reactor core system for facilitating removal of contaminating fission products, as they are fermed, from association with the flssionable fuel, so as to mitigate the interferent effects of such fission products during reactor operation. The fuel elements are comprised of tubular members impervious to fluid and contatning on their interior surfaces a thin layer of fissionable material providing a central void. The core structure is comprised of a plurality of the tubular fuel elements arranged in parallel and a closed manifold connected to their ends. In the reactor the core structure is dispersed in a water moderator and coolant within a pressure vessel, and a means connected to said manifuld is provided for withdrawing and disposing of mobile fission product contamination from the interior of the feel tubes and manifold.

  13. Fast Flux Test Facility core system

    SciTech Connect

    Ethridge, J.L. ); Baker, R.B.; Leggett, R.D.; Pitner, A.L.; Waltar, A.E. )

    1990-11-01

    A review of Liquid Metal Reactor (LMR) core system accomplishments provides an excellent road map through the maze of issues that faced reactor designers 10 years ago. At that time relatively large uncertainties were associated with fuel pin and fuel assembly performance, irradiation of structural materials, and performance of absorber assemblies. The extensive core systems irradiation program at the US Department of Energy's Fast Flux Test Facility (FFTF) has addressed each of these principal issues. As a result of the progress made, the attention of long-range LMR planners and designers can shift away from improving core systems and focus on reducing capital costs to ensure the LMR can compete economically in the 21st century with other nuclear reactor concepts. 3 refs., 6 figs., 1 tab.

  14. Stretchable inductor with liquid magnetic core

    NASA Astrophysics Data System (ADS)

    Lazarus, N.; Meyer, C. D.

    2016-03-01

    Adding magnetic materials is a well-established method for improving performance of inductors. However, traditional magnetic cores are rigid and poorly suited for the emerging field of stretchable electronics, where highly deformable inductors are used to wirelessly couple power and data signals. In this work, stretchable inductors are demonstrated based on the use of ferrofluids, magnetic liquids based on distributed magnetic particles, to create a compliant magnetic core. Using a silicone molding technique to create multi-layer fluidic channels, a liquid metal solenoid is fabricated around a ferrofluid channel. An analytical model is developed for the effects of mechanical strain, followed by experimental verification using two different ferrofluids with different permeabilities. Adding ferrofluid was found to increase the unstrained inductance by up to 280% relative to a similar inductor with a non-magnetic silicone core, while retaining the ability to survive uniaxial strains up to 100%.

  15. Core and Geodynamo Evolution and the Influence of Potassium

    NASA Astrophysics Data System (ADS)

    Nimmo, F.; Price, G. D.; Brodholt, J.

    2002-12-01

    In his penultimate paragraph, Birch (1952) notes that the growth of the inner core is controlled by its melting curve, which ``. . . has implications for the `hydromagnetic' theories of the Earth's magnetism''. Although the terminology has changed, the relationship between the growth of the inner core and the geodynamo is still an area of active research, and is still limited by our imperfect understanding of core properties. The ability of the Earth's core to sustain a geodynamo depends on the entropy produced by core cooling and/or solidification [1,2]. The rate of cooling depends on the rate at which the mantle extracts heat from the core. In this contribution we model the coupled thermal evolution of the core and mantle [3,4,5] to investigate the circumstances under which the geodynamo can have been sustained for at least 3~Ga. In particular, we use improved estimates of core properties [6], and examine the effect of potassium in the core, as suggested by recent theoretical [7] and experimental [8] studies. Models without potassium in the core and with realistic present-day temperature and viscosity structures can sustain a geodynamo. However, for the nominal core parameters these models produce an inner core which is too large. For reasonable mantle viscosities, the core cools too rapidly; a reduced cooling rate produces a smaller inner core but requires unreasonable viscosities. The robustness of this result depends mainly on uncertainties in the solidus temperature of the core and the mean thermal expansivity of the mantle. Introducing potassium into the core retards the rate of core growth [7] and provides an additional source of entropy [1]. For a core potassium content of 100-400ppm [8], the criteria of mantle and core temperature and viscosity structure, inner core radius and geodynamo generation can all be satisfied. [1] Gubbins, D. et al., GJRAS 59, 57-99, 1979. [2] Buffett, B.A. et al., JGR 101, 7989-8006, 1996. [3] Mollett, S., GJRAS 76, 653

  16. Analytical Chemistry Core Capability Assessment - Preliminary Report

    SciTech Connect

    Barr, Mary E.; Farish, Thomas J.

    2012-05-16

    The concept of 'core capability' can be nebulous one. Even at a fairly specific level, where core capability equals maintaining essential services, it is highly dependent upon the perspective of the requestor. Samples are submitted to analytical services because the requesters do not have the capability to conduct adequate analyses themselves. Some requests are for general chemical information in support of R and D, process control, or process improvement. Many analyses, however, are part of a product certification package and must comply with higher-level customer quality assurance requirements. So which services are essential to that customer - just those for product certification? Does the customer also (indirectly) need services that support process control and improvement? And what is the timeframe? Capability is often expressed in terms of the currently utilized procedures, and most programmatic customers can only plan a few years out, at best. But should core capability consider the long term where new technologies, aging facilities, and personnel replacements must be considered? These questions, and a multitude of others, explain why attempts to gain long-term consensus on the definition of core capability have consistently failed. This preliminary report will not try to define core capability for any specific program or set of programs. Instead, it will try to address the underlying concerns that drive the desire to determine core capability. Essentially, programmatic customers want to be able to call upon analytical chemistry services to provide all the assays they need, and they don't want to pay for analytical chemistry services they don't currently use (or use infrequently). This report will focus on explaining how the current analytical capabilities and methods evolved to serve a variety of needs with a focus on why some analytes have multiple analytical techniques, and what determines the infrastructure for these analyses. This information will be

  17. Selenium semiconductor core optical fibers

    SciTech Connect

    Tang, G. W.; Qian, Q. Peng, K. L.; Wen, X.; Zhou, G. X.; Sun, M.; Chen, X. D.; Yang, Z. M.

    2015-02-15

    Phosphate glass-clad optical fibers containing selenium (Se) semiconductor core were fabricated using a molten core method. The cores were found to be amorphous as evidenced by X-ray diffraction and corroborated by Micro-Raman spectrum. Elemental analysis across the core/clad interface suggests that there is some diffusion of about 3 wt % oxygen in the core region. Phosphate glass-clad crystalline selenium core optical fibers were obtained by a postdrawing annealing process. A two-cm-long crystalline selenium semiconductor core optical fibers, electrically contacted to external circuitry through the fiber end facets, exhibit a three times change in conductivity between dark and illuminated states. Such crystalline selenium semiconductor core optical fibers have promising utility in optical switch and photoconductivity of optical fiber array.

  18. Core Formation Process and Light Elements in the Planetary Core

    NASA Astrophysics Data System (ADS)

    Ohtani, E.; Sakairi, T.; Watanabe, K.; Kamada, S.; Sakamaki, T.; Hirao, N.

    2015-12-01

    Si, O, and S are major candidates for light elements in the planetary core. In the early stage of the planetary formation, the core formation started by percolation of the metallic liquid though silicate matrix because Fe-S-O and Fe-S-Si eutectic temperatures are significantly lower than the solidus of the silicates. Therefore, in the early stage of accretion of the planets, the eutectic liquid with S enrichment was formed and separated into the core by percolation. The major light element in the core at this stage will be sulfur. The internal pressure and temperature increased with the growth of the planets, and the metal component depleted in S was molten. The metallic melt contained both Si and O at high pressure in the deep magma ocean in the later stage. Thus, the core contains S, Si, and O in this stage of core formation. Partitioning experiments between solid and liquid metals indicate that S is partitioned into the liquid metal, whereas O is weakly into the liquid. Partitioning of Si changes with the metallic iron phases, i.e., fcc iron-alloy coexisting with the metallic liquid below 30 GPa is depleted in Si. Whereas hcp-Fe alloy above 30 GPa coexisting with the liquid favors Si. This contrast of Si partitioning provides remarkable difference in compositions of the solid inner core and liquid outer core among different terrestrial planets. Our melting experiments of the Fe-S-Si and Fe-O-S systems at high pressure indicate the core-adiabats in small planets, Mercury and Mars, are greater than the slope of the solidus and liquidus curves of these systems. Thus, in these planets, the core crystallized at the top of the liquid core and 'snowing core' formation occurred during crystallization. The solid inner core is depleted in both Si and S whereas the liquid outer core is relatively enriched in Si and S in these planets. On the other hand, the core adiabats in large planets, Earth and Venus, are smaller than the solidus and liquidus curves of the systems. The

  19. Sneak in Some Core Subjects

    ERIC Educational Resources Information Center

    Clarke, Lynne

    2011-01-01

    Even if students don't have an aversion to core subjects, they may not see the relationship between the core subjects and their career path. In this article, the author outlines a career path project that can be adapted to work in any career and technical education (CTE) class to highlight the relationship between core subjects and the real world.…

  20. Hollow-Core Fiber Lamp

    NASA Technical Reports Server (NTRS)

    Yi, Lin (Inventor); Tjoelker, Robert L. (Inventor); Burt, Eric A. (Inventor); Huang, Shouhua (Inventor)

    2016-01-01

    Hollow-core capillary discharge lamps on the millimeter or sub-millimeter scale are provided. The hollow-core capillary discharge lamps achieve an increased light intensity ratio between 194 millimeters (useful) and 254 millimeters (useless) light than conventional lamps. The capillary discharge lamps may include a cone to increase light output. Hollow-core photonic crystal fiber (HCPCF) may also be used.

  1. Effect of core polarizability on photoionization cross-section calculations.

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, R. C.

    1972-01-01

    Demonstration of the importance of core polarizability in a case where cancellation is only moderate, with suggestion of an improvement to the scaled Thomas-Fermi (STF) wave functions of Stewart and Rotenberg (1965). The inclusion of dipole polarizability of the core for argon is shown to substantially improve the agreement between the theoretical and experimental photoionization cross sections for the ground-state configuration.

  2. WEAVE core processing system

    NASA Astrophysics Data System (ADS)

    Walton, Nicholas A.; Irwin, Mike; Lewis, James R.; Gonzalez-Solares, Eduardo; Dalton, Gavin; Trager, Scott; Aguerri, J. Alfonso L.; Allende Prieto, Carlos; Benn, Chris R.; Abrams, Don Carlos; Picó, Sergio; Middleton, Kevin; Lodi, Marcello; Bonifacio, Piercarlo

    2014-07-01

    WEAVE is an approved massive wide field multi-object optical spectrograph (MOS) currently entering its build phase, destined for use on the 4.2-m William Herschel Telescope (WHT). It will be commissioned and begin survey operations in 2017. This paper describes the core processing system (CPS) system being developed to process the bulk data flow from WEAVE. We describe the processes and techniques to be used in producing the scientifically validated 'Level 1' data products from the WEAVE data. CPS outputs will include calibrated one-d spectra and initial estimates of basic parameters such as radial velocities (for stars) and redshifts (for galaxies).

  3. Automated Core Design

    SciTech Connect

    Kobayashi, Yoko; Aiyoshi, Eitaro

    2005-07-15

    Multistate searching methods are a subfield of distributed artificial intelligence that aims to provide both principles for construction of complex systems involving multiple states and mechanisms for coordination of independent agents' actions. This paper proposes a multistate searching algorithm with reinforcement learning for the automatic core design of a boiling water reactor. The characteristics of this algorithm are that the coupling structure and the coupling operation suitable for the assigned problem are assumed and an optimal solution is obtained by mutual interference in multistate transitions using multiagents. Calculations in an actual plant confirmed that the proposed algorithm increased the convergence ability of the optimization process.

  4. PROCESS FOR JACKETING A CORE

    DOEpatents

    Last, G.A.

    1960-07-19

    A process is given for enclosing the uranium core of a nuclear fuel element by placing the core in an aluminum cup and closing the open end of the cup over the core. As the metal of the cup is brought together in a weld over the center of the end of the core, it is extruded inwardly as internal projection into a central recess in the core and outwardly as an external projection. Thus oxide inclusions in the weld of the cup are spread out into the internal and external projections and do not interfere with the integrity of the weld.

  5. Models of the Earth's Core.

    PubMed

    Stevenson, D J

    1981-11-01

    Combined inferences from seismology, high-pressure experiment and theory, geomagnetism, fluid dynamics, and current views of terrestrial planetary evolution lead to models of the earth's core with the following properties. Core formation was contemporaneous with earth accretion; the core is not in chemical equilibrium with the mantle; the outer core is a fluid iron alloy containing significant quantities of lighter elements and is probably almost adiabatic and compositionally uniform; the more iron-rich inner solid core is a consequence of partial freezing of the outer core, and the energy release from this process sustains the earth's magnetic field; and the thermodynamic properties of the core are well constrained by the application of liquid-state theory to seismic and laboratory data. PMID:17839632

  6. Core-tube data logger

    SciTech Connect

    Henfling, J.A.; Normann, R.A.; Knudsen, S.; Drumheller, D.

    1997-01-01

    Wireline core drilling, increasingly used for geothermal exploration, employs a core-tube to capture a rock core sample during drilling. Three types of core-tube data loggers (CTDL) have been built and tested to date by Sandia national Laboratories. They are: (1) temperature-only logger, (2) temperature/inclinometer logger and (3) heat-shielded temperature/inclinometer logger. All were tested during core drilling operations using standard wireline diamond core drilling equipment. While these tools are designed for core-tube deployment, the tool lends itself to be adapted to other drilling modes and equipment. Topics covered in this paper include: (1) description on how the CTDLs are implemented, (2) the components of the system, (3) the type of data one can expect from this type of tool, (4) lessons learned, (5) comparison to its counterpart and (6) future work.

  7. Core fluctuations test. Revision 1

    SciTech Connect

    Betts, W.S.

    1987-06-01

    Fluctuations were first encountered in the Fort St. Vrain reactor early in cycle 1 operation, during the initial rise from 40% to 70% power. Subsequent in-core tests and operation throughout cycles 1 and 2 demonstrated that fluctuations were repeatable, occurring at core pressure drops of between 2.5 psi and 4.0 psi, and that in each instance their characteristics were very similar. Subsequently, tests and analysis were done to understand the core fluctuation phenomenon. These efforts also lead to a design fix which stopped these fluctuations in the FSV reactor core. This fix required that keys be used in addition to the keys in the core support floor which already existed. This report outlines a test plan to validate that core fluctuations will not occur in the MHTGR core. 2 refs., 12 figs., 3 tabs.

  8. Are medical residents a "core group" for future improvement of influenza vaccination coverage in health-care workers? A study among medical residents at the University Hospital of Palermo (Sicily).

    PubMed

    Amodio, Emanuele; Tramuto, Fabio; Maringhini, Guido; Asciutto, Rosario; Firenze, Alberto; Vitale, Francesco; Costantino, Claudio; Calamusa, Giuseppe

    2011-10-19

    residents appears to be habitual, with little comprehension of the rationale and logic for vaccination, including the need to be vaccinated to protect patients from nosocomial influenza infection. Our study suggests the importance of prioritizing residents for vaccination campaigns, as they represent "the future" and include a core group that habitually accepts vaccination.

  9. PRESSURIZED WATER REACTOR CORE WITH PLUTONIUM BURNUP

    DOEpatents

    Puechl, K.H.

    1963-09-24

    A pressurized water reactor is described having a core containing Pu/sup 240/ in which the effective microscopic neutronabsorption cross section of Pu/sup 240/ in unconverted condition decreases as the time of operation of the reactor increases, in order to compensate for loss of reactivity resulting from fission product buildup during reactor operation. This means serves to improve the efficiency of the reactor operation by reducing power losses resulting from control rods and burnable poisons. (AEC)

  10. Raman Reporter-Coupled Ag(core)@Au(shell) Nanostars for in Vivo Improved Surface Enhanced Raman Scattering Imaging and Near-infrared-Triggered Photothermal Therapy in Breast Cancers.

    PubMed

    Zeng, Leyong; Pan, Yuanwei; Wang, Shouju; Wang, Xin; Zhao, Xinmei; Ren, Wenzhi; Lu, Guangming; Wu, Aiguo

    2015-08-01

    Noble-metal nanomaterials were widely investigated as theranostic systems for surface enhanced Raman scattering (SERS) imaging, and also for photothermal therapy (PTT) of cancers. However, it was still a major challenge to explore multifunctional nanoprobes with high performance, high stability, and low toxicity. In this work, Raman reporter (DTTC)-coupled Agcore@Aushell nanostars (Ag@Au-DTTC) were synthesized and investigated for in vivo improved SERS imaging and near-infrared (NIR)-triggered PTT of breast cancers. By the two-step coupling of DTTC, the SERS signal was improved obviously, and the cytotoxicity of nanoparticles was also decreased by coating Au nanostars onto Ag nanoparticles. The as-prepared Ag@Au-DTTC nanostars showed high photostability and excellent photothermal performance, in which the photothermal conversion efficiency was up to 79.01% under the irradiation of an 808 nm laser. The in vitro and in vivo SERS measurements of Ag@Au-DTTC nanostars showed that the many sharp and narrow Raman peaks located at 508, 782, 844, 1135, 1242, 1331, 1464, 1510, and 1580 cm(-1) could be obviously observed in MCF-7 cells and in MCF-7 tumor-bearing nude mice, compared with that in pure DTTC. In 14-day treatments, the tumor volume of MCF-7 tumor-bearing nude mice injected with Ag@Au-DTTC nanostars and irradiated by an 808 nm laser almost disappeared. This study demonstrated that the as-prepared Ag@Au-DTTC nanostars could be excellent multifunctional agents for improved SERS imaging and NIR-triggered PTT of breast cancers with low risk. PMID:26204589

  11. Monte Carlo Neutronics and Thermal Hydraulics Analysis of Reactor Cores with Multilevel Grids

    NASA Astrophysics Data System (ADS)

    Bernnat, W.; Mattes, M.; Guilliard, N.; Lapins, J.; Zwermann, W.; Pasichnyk, I.; Velkov, K.

    2014-06-01

    Power reactors are composed of assemblies with fuel pin lattices or other repeated structures with several grid levels, which can be modeled in detail by Monte Carlo neutronics codes such as MCNP6 using corresponding lattice options, even for large cores. Except for fresh cores at beginning of life, there is a varying material distribution due to burnup in the different fuel pins. Additionally, for power states the fuel and moderator temperatures and moderator densities vary according to the power distribution and cooling conditions. Therefore, a coupling of the neutronics code with a thermal hydraulics code is necessary. Depending on the level of detail of the analysis, a very large number of cells with different materials and temperatures must be regarded. The assignment of different material properties to all elements of a multilevel grid is very elaborate and may exceed program limits if the standard input procedure is used. Therefore, an internal assignment is used which overrides uniform input parameters. The temperature dependency of continuous energy cross sections, probability tables for the unresolved resonance region and thermal neutron scattering laws is taken into account by interpolation, requiring only a limited number of data sets generated for different temperatures. The method is applied with MCNP6 and proven for several full core reactor models. For the coupling of MCNP6 with thermal hydraulics appropriate interfaces were developed for the GRS system code ATHLET for liquid coolant and the IKE thermal hydraulics code ATTICA-3D for gaseous coolant. Examples will be shown for different applications for PWRs with square and hexagonal lattices, fast reactors (SFR) with hexagonal lattices and HTRs with pebble bed and prismatic lattices.

  12. The Earth's Inner Core: a Black Box

    NASA Astrophysics Data System (ADS)

    Tkalčić, Hrvoje

    2016-04-01

    that interact with the inner core boundary. iv) Recent studies have revealed complex structures in the lowermost mantle and outermost inner core that impose complex boundary conditions on the geodynamo. It is possible that the lowermost mantle structure is "mapped" onto the surface of the inner core through convection patterns in the outer core. There is much potential to make further progress on this topic due to the improving quality and increasing number of data and the continual advancements in mathematical geophysics, which can now provide uncertainty maps in addition to tomograms. v) The rotational dynamics of the inner core is still not well understood despite recent progress. While this topic is difficult to address seismologically due to the lack of the north-south ray-paths, the emergence of novel approaches to inverse problems and new seismological classes of data, such as interferometry datasets, is promising.

  13. Complex coacervate core micelles.

    PubMed

    Voets, Ilja K; de Keizer, Arie; Cohen Stuart, Martien A

    2009-01-01

    In this review we present an overview of the literature on the co-assembly of neutral-ionic block, graft, and random copolymers with oppositely charged species in aqueous solution. Oppositely charged species include synthetic (co)polymers of various architectures, biopolymers - such as proteins, enzymes and DNA - multivalent ions, metallic nanoparticles, low molecular weight surfactants, polyelectrolyte block copolymer micelles, metallo-supramolecular polymers, equilibrium polymers, etcetera. The resultant structures are termed complex coacervate core/polyion complex/block ionomer complex/interpolyelectrolyte complex micelles (or vesicles); i.e., in short C3Ms (or C3Vs) and PIC, BIC or IPEC micelles (and vesicles). Formation, structure, dynamics, properties, and function will be discussed. We focus on experimental work; theory and modelling will not be discussed. Recent developments in applications and micelles with heterogeneous coronas are emphasized.

  14. HTTF Core Stress Analysis

    SciTech Connect

    Brian D. Hawkes; Richard Schultz

    2012-07-01

    In accordance with the need to determine whether cracking of the ceramic core disks which will be constructed and used in the High Temperature Test Facility (HTTF) for heatup and cooldown experiments, a set of calculation were performed using Abaqus to investigate the thermal stresses levels and likelihood for cracking. The calculations showed that using the material properties provided for the Greencast 94F ceramic, cracking is predicted to occur. However, this modeling does not predict the size or length of the actual cracks. It is quite likely that cracks will be narrow with rough walls which would impede the flow of coolant gases entering the cracks. Based on data recorded at Oregon State University using Greencast 94F samples that were heated and cooled at prescribed rates, it was concluded that the likelihood that the cracks would be detrimental to the experimental objectives is small.

  15. NEUTRONIC REACTOR CORE INSTRUMENT

    DOEpatents

    Mims, L.S.

    1961-08-22

    A multi-purpose instrument for measuring neutron flux, coolant flow rate, and coolant temperature in a nuclear reactor is described. The device consists essentially of a hollow thimble containing a heat conducting element protruding from the inner wall, the element containing on its innermost end an amount of fissionsble materinl to function as a heat source when subjected to neutron flux irradiation. Thermocouple type temperature sensing means are placed on the heat conducting element adjacent the fissionable material and at a point spaced therefrom, and at a point on the thimble which is in contact with the coolant fluid. The temperature differentials measured between the thermocouples are determinative of the neutron flux, coolant flow, and temperature being measured. The device may be utilized as a probe or may be incorporated in a reactor core. (AE C)

  16. Growth outside the core.

    PubMed

    Zook, Chris; Allen, James

    2003-12-01

    Growth in an adjacent market is tougher than it looks; three-quarters of the time, the effort fails. But companies can change those odds dramatically. Results from a five-year study of corporate growth conducted by Bain & Company reveal that adjacency expansion succeeds only when built around strong core businesses that have the potential to become market leaders. And the best place to look for adjacency opportunities is inside a company's strongest customers. The study also found that the most successful companies were able to consistently, profitably outgrow their rivals by developing a formula for pushing out the boundaries of their core businesses in predictable, repeatable ways. Companies use their repeatability formulas to expand into any number of adjacencies. Some companies make repeated geographic moves, as Vodafone has done in expanding from one geographic market to another over the past 13 years, building revenues from $1 billion in 1990 to $48 billion in 2003. Others apply a superior business model to new segments. Dell, for example, has repeatedly adapted its direct-to-customer model to new customer segments and new product categories. In other cases, companies develop hybrid approaches. Nike executed a series of different types of adjacency moves: it expanded into adjacent customer segments, introduced new products, developed new distribution channels, and then moved into adjacent geographic markets. The successful repeaters in the study had two common characteristics. First, they were extraordinarily disciplined, applying rigorous screens before they made an adjacency move. This discipline paid off in the form of learning curve benefits, increased speed, and lower complexity. And second, in almost all cases, they developed their repeatable formulas by studying their customers and their customers' economics very, very carefully.

  17. Building An Astronaut Core

    NASA Video Gallery

    Train to improve the strength in your abdominal and back muscles by performing the "Commander Crunch" and "Pilot Plank" exercises. The Train Like an Astronaut project uses the excitement of explora...

  18. Formation, history and energetics of cores in the terrestrial planets

    NASA Technical Reports Server (NTRS)

    Solomon, S. C.

    1979-01-01

    The size, evolution and energetics of the earth's core and the probable central, metalic cores of Mercury, Venus, the moon and Mars are discussed. The cores of Mercury, Mars and the earth are considered likely to decrease in relative mass and volume with distance from the sun; the moon does not fit this sequence and data from Venus are insufficient. Core formation is concluded to have occurred early (prior to four billion years ago) on the earth and Mercury, while that on the moon would have occurred over a longer interval and the core of Mars would have formed much later. Of the possible energy sources in planetary cores able to maintain a molten state and drive magnetic dynamos, the energy of core formation was probably spent too early in planetary history to provide much present power, and the energy gained from freezing an inner core in the earth and Mercury are considered at best marginally able to match conductive heat loss. Future measurements proposed to improve the quantitative understanding of core properties include a better documentation of the magnetic fields of Venus and Mars and the seismometry of Mars.

  19. Advances in core drilling technology

    NASA Astrophysics Data System (ADS)

    Holdsworth, G.

    Some notable technical advances in drill design were reported at the meeting, held in Canada August 30-September 1, 1982, at the University of Calgary. Chief amongst these was a battery powered, computer assisted electromechanical core drill which has recently been used by the Danes in Greenland to continuously core to the base of the ice sheet at 2038 m. This is the deepest coring operation so far on the Greenland ice sheet. (The record for deep glacier drilling is held by the U.S. Army Cold Regions Research and Engineering Laboratory for the continuous coring through 2164 m of ice to bedrock at Byrd Station, Antarctica, in 1968). In early 1982, a current Soviet core drilling operation was reported to be at a depth of 2000 m at Vostok station, Antarctica, where the total ice thickness is about 4000 m; the goal of core drilling the entire ice thickness there could be achieved before the end of 1983.

  20. Measurements of ethane in Antarctic ice cores

    NASA Astrophysics Data System (ADS)

    Verhulst, K. R.; Fosse, E. K.; Aydin, K. M.; Saltzman, E. S.

    2011-12-01

    Ethane is one of the most abundant hydrocarbons in the atmosphere. The major ethane sources are fossil fuel production and use, biofuel combustion, and biomass-burning emissions and the primary loss pathway is via reaction with OH. A paleoatmospheric ethane record would be useful as a tracer of biomass-burning emissions, providing a constraint on past changes in atmospheric methane and methane isotopes. An independent biomass-burning tracer would improve our understanding of the relationship between biomass burning and climate. The mean annual atmospheric ethane level at high southern latitudes is about 230 parts per trillion (ppt), and Antarctic firn air measurements suggest that atmospheric ethane levels in the early 20th century were considerably lower (Aydin et al., 2011). In this study, we present preliminary measurements of ethane (C2H6) in Antarctic ice core samples with gas ages ranging from 0-1900 C.E. Samples were obtained from dry-drilled ice cores from South Pole and Vostok in East Antarctica, and from the West Antarctic Ice Sheet Divide (WAIS-D). Gases were extracted from the ice by melting under vacuum in a glass vessel sealed by indium wire and were analyzed using high resolution GC/MS with isotope dilution. Ethane levels measured in ice core samples were in the range 100-220 ppt, with a mean of 157 ± 45 ppt (n=12). System blanks contribute roughly half the amount of ethane extracted from a 300 g ice core sample. These preliminary data exhibit a temporal trend, with higher ethane levels from 0-900 C.E., followed by a decline, reaching a minimum between 1600-1700 C.E. These trends are consistent with variations in ice core methane isotopes and carbon monoxide isotopes (Ferretti et al., 2005, Wang et al., 2010), which indicate changes in biomass burning emissions over this time period. These preliminary data suggest that Antarctic ice core bubbles contain paleoatmospheric ethane levels. With further improvement of laboratory techniques it appears

  1. A survey of alternative once-through fast reactor core designs

    SciTech Connect

    Fei, T.; Richard, J. G.; Kersting, A. R.; Don, S. M.; Oi, C.; Driscoll, M. J.; Shwageraus, E.

    2012-07-01

    Reprocessing of Light Water Reactor (LWR) spent fuel to recover plutonium or transuranics for use in Sodium cooled Fast Reactors (SFRs) is a distant prospect in the U.S.A. This has motivated our evaluation of potentially cost-effective operation of uranium startup fast reactors (USFRs) in a once-through mode. This review goes beyond findings reported earlier based on a UC fueled MgO reflected SFR to describe a broader parametric study of options. Cores were evaluated for a variety of fuel/coolant/reflector combinations: UC/UZr/UO{sub 2}/UN;Na/Pb; MgO/SS/Zr. The challenge is achieving high burnup while minimizing enrichment and respecting both cladding fluence/dpa and reactivity lifetime limits. These parametric studies show that while UC fuel is still the leading contender, UO{sub 2} fuel and ZrH 1.7 moderated metallic fuel are also attractive if UC proves to be otherwise inadequate. Overall, these findings support the conclusion that a competitive fuel cycle cost and uranium utilization compared to LWRs is possible for SFRs operated on a once-through uranium fueled fuel cycle. In addition, eventual transition to TRU recycle mode is studied, as is a small test reactor to demonstrate key features. (authors)

  2. GPM Core Observatory Launch Animation

    NASA Video Gallery

    This animation depicts the launch of the Global Precipitation Measurement (GPM) Core Observatory satellite from Tanegashima Space Center, Japan. The launch is currently scheduled for Feb. 27, 2014....

  3. Glass-clad semiconductor core optical fibers

    NASA Astrophysics Data System (ADS)

    Morris, Stephanie Lynn

    Glass-clad optical fibers comprising a crystalline semiconductor core have garnered considerable recent attention for their potential utility as novel waveguides for applications in nonlinear optics, sensing, power delivery, and biomedicine. As research into these fibers has progressed, it has become evident that excessive losses are limiting performance and so greater understanding of the underlying materials science, coupled with advances in fiber processing, is needed. More specifically, the semiconductor core fibers possess three performance-limiting characteristics that need to be addressed: (a) thermal expansion mismatches between crystalline core and glass cladding that lead to cracks, (b) the precipitation of oxide species in the core upon fiber cooling, which results from partial dissolution of the cladding glass by the core melt, and (c) polycrystallinity; all of which lead to scattering and increased transmission losses. This dissertation systematically studies each of these effects and develops both a fundamental scientific understanding of and practical engineering methods for reducing their impact. With respect to the thermal expansion mismatch and, in part, the dissolution of oxides, for the first time to our knowledge, oxide and non-oxide glass compositions are developed for a series of semiconductor cores based on two main design criteria: (1) matching the thermal expansion coefficient between semiconductor core and glass cladding to minimize cracking and (2) matching the viscosity-temperature dependences, such that the cladding glass draws into fiber at a temperature slightly above the melting point of the semiconductor in order to minimize dissolution and improve the fiber draw process. The x[Na 2O:Al2O3] + (100 - 2x)SiO2 glass compositional family was selected due to the ability to tailor the glass properties to match the aforementioned targets through slight variations in composition and adjusting the ratios of bridging and non-bridging oxygen

  4. Enhanced Core Noise Modeling for Turbofan Engines

    NASA Technical Reports Server (NTRS)

    Stone, James R.; Krejsa, Eugene A.; Clark, Bruce J.

    2011-01-01

    This report describes work performed by MTC Technologies (MTCT) for NASA Glenn Research Center (GRC) under Contract NAS3-00178, Task Order No. 15. MTCT previously developed a first-generation empirical model that correlates the core/combustion noise of four GE engines, the CF6, CF34, CFM56, and GE90 for General Electric (GE) under Contract No. 200-1X-14W53048, in support of GRC Contract NAS3-01135. MTCT has demonstrated in earlier noise modeling efforts that the improvement of predictive modeling is greatly enhanced by an iterative approach, so in support of NASA's Quiet Aircraft Technology Project, GRC sponsored this effort to improve the model. Since the noise data available for correlation are total engine noise spectra, it is total engine noise that must be predicted. Since the scope of this effort was not sufficient to explore fan and turbine noise, the most meaningful comparisons must be restricted to frequencies below the blade passage frequency. Below the blade passage frequency and at relatively high power settings jet noise is expected to be the dominant source, and comparisons are shown that demonstrate the accuracy of the jet noise model recently developed by MTCT for NASA under Contract NAS3-00178, Task Order No. 10. At lower power settings the core noise became most apparent, and these data corrected for the contribution of jet noise were then used to establish the characteristics of core noise. There is clearly more than one spectral range where core noise is evident, so the spectral approach developed by von Glahn and Krejsa in 1982 wherein four spectral regions overlap, was used in the GE effort. Further analysis indicates that the two higher frequency components, which are often somewhat masked by turbomachinery noise, can be treated as one component, and it is on that basis that the current model is formulated. The frequency scaling relationships are improved and are now based on combustor and core nozzle geometries. In conjunction with the Task

  5. Lunar Fluid Core and Solid-Body Tides

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.

    2005-01-01

    Variations in rotation and orientation of the Moon are sensitive to solid-body tidal dissipation, dissipation due to relative motion at the fluid-core/solid-mantle boundary, and tidal Love number k2 [1,2]. There is weaker sensitivity to flattening of the core-mantle boundary (CMB) [2-5] and fluid core moment of inertia [1]. Accurate Lunar Laser Ranging (LLR) measurements of the distance from observatories on the Earth to four retroreflector arrays on the Moon are sensitive to lunar rotation and orientation variations and tidal displacements. Past solutions using the LLR data have given results for dissipation due to solid-body tides and fluid core [1] plus Love number [1-5]. Detection of CMB flattening has been improving [3,5] and now seems significant. This strengthens the case for a fluid lunar core.

  6. IN-CORE FUEL MANAGEMENT: PWR Core Calculations Using MCRAC

    NASA Astrophysics Data System (ADS)

    PetroviĆ, B. G.

    1991-01-01

    The following sections are included: * INTRODUCTION * IN-CORE FUEL MANAGEMENT CALCULATIONS * In-Core Fuel Management * Methodological Problems of In-Core Fuel Management * In-Core Fuel Management Analytical Tools * PENN STATE FUEL MANAGEMENT PACKAGE * Penn State Fuel Management Package (PFMP) * Assembly Data Description (ADD) * Linking PSU-LEOPARD and MCRAC: An Example * MULTICYCLE REACTOR ANALYSIS CODE (MCRAC) * Main Features and Options of MCRAC code * Core geometry * Diffusion equations * 1.5-group model * Multicycle neutronic analysis * Multicycle cost analysis * Criticality search * Power-dependent xenon feedback calculations * Control rod and burnable absorber simulation * Search for LP with flat BOC power distribution * Artificial ADD option * Variable dimensioning technique * RBI version of MCRAC code * Programming changes in PC version * Fuel interchange option * MCRAC Input/Output * General input description * Sample input * Sample output * EXPERIENCE WITH MCRAC CODE * CONCLUSIONS * REFERENCES

  7. Variable depth core sampler

    SciTech Connect

    Bourgeois, P.M.; Reger, R.J.

    1994-12-31

    This invention relates to a sampling means, more particularly to a device to sample hard surfaces at varying depths. Often it is desirable to take samples of a hard surface wherein the samples are of the same diameter but of varying depths. Current practice requires that a full top-to-bottom sample of the material be taken, using a hole saw, and boring a hole from one end of the material to the other. The sample thus taken is removed from the hole saw and the middle of said sample is then subjected to further investigation. This paper describes a variable depth core sampler comprimising a circular hole saw member, having longitudinal sections that collapse to form a point and capture a sample, and a second saw member residing inside the first hole saw member to support the longitudinal sections of the first member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside the the first hole saw member.

  8. Global Core Plasma Model

    NASA Technical Reports Server (NTRS)

    Gallagher, Dennis L.; Craven, Paul D.; Comfort, Richard H.

    1999-01-01

    Over 40 years of ground and spacecraft plasmaspheric measurements have resulted in many statistical descriptions of plasmaspheric properties. In some cases, these properties have been represented as analytical descriptions that are valid for specific regions or conditions. For the most part, what has not been done is to extend regional empirical descriptions or models to the plasmasphere as a whole. In contrast, many related investigations depend on the use of representative plasmaspheric conditions throughout the inner magnetosphere. Wave propagation, involving the transport of energy through the magnetosphere, is strongly affected by thermal plasma density and its composition. Ring current collisional and wave particle losses also strongly depend on these quantities. Plasmaspheric also plays a secondary role in influencing radio signals from the Global Positioning System satellites. The Global Core Plasma Model (GCPM) is an attempt to assimilate previous empirical evidence and regional models for plasmaspheric density into a continuous, smooth model of thermal plasma density in the inner magnetosphere. In that spirit, the International Reference Ionosphere is currently used to complete the low altitude description of density and composition in the model. The models and measurements on which the GCPM is currently based and its relationship to IRI will be discussed.

  9. Adult educators' core competences

    NASA Astrophysics Data System (ADS)

    Wahlgren, Bjarne

    2016-06-01

    Which competences do professional adult educators need? This research note discusses the topic from a comparative perspective, finding that adult educators' required competences are wide-ranging, heterogeneous and complex. They are subject to context in terms of national and cultural environment as well as the kind of adult education concerned (e.g. basic education, work-related education etc.). However, it seems that it is possible to identify certain competence requirements which transcend national, cultural and functional boundaries. This research note summarises these common or "core" requirements, organising them into four thematic subcategories: (1) communicating subject knowledge; (2) taking students' prior learning into account; (3) supporting a learning environment; and (4) the adult educator's reflection on his or her own performance. At the end of his analysis of different competence profiles, the author notes that adult educators' ability to train adult learners in a way which then enables them to apply and use what they have learned in practice (thus performing knowledge transfer) still seems to be overlooked.

  10. Uncovering the information core in recommender systems

    NASA Astrophysics Data System (ADS)

    Zeng, Wei; Zeng, An; Liu, Hao; Shang, Ming-Sheng; Zhou, Tao

    2014-08-01

    With the rapid growth of the Internet and overwhelming amount of information that people are confronted with, recommender systems have been developed to effectively support users' decision-making process in online systems. So far, much attention has been paid to designing new recommendation algorithms and improving existent ones. However, few works considered the different contributions from different users to the performance of a recommender system. Such studies can help us improve the recommendation efficiency by excluding irrelevant users. In this paper, we argue that in each online system there exists a group of core users who carry most of the information for recommendation. With them, the recommender systems can already generate satisfactory recommendation. Our core user extraction method enables the recommender systems to achieve 90% of the accuracy of the top-L recommendation by taking only 20% of the users into account. A detailed investigation reveals that these core users are not necessarily the large-degree users. Moreover, they tend to select high quality objects and their selections are well diversified.

  11. Uncovering the information core in recommender systems.

    PubMed

    Zeng, Wei; Zeng, An; Liu, Hao; Shang, Ming-Sheng; Zhou, Tao

    2014-08-21

    With the rapid growth of the Internet and overwhelming amount of information that people are confronted with, recommender systems have been developed to effectively support users' decision-making process in online systems. So far, much attention has been paid to designing new recommendation algorithms and improving existent ones. However, few works considered the different contributions from different users to the performance of a recommender system. Such studies can help us improve the recommendation efficiency by excluding irrelevant users. In this paper, we argue that in each online system there exists a group of core users who carry most of the information for recommendation. With them, the recommender systems can already generate satisfactory recommendation. Our core user extraction method enables the recommender systems to achieve 90% of the accuracy of the top-L recommendation by taking only 20% of the users into account. A detailed investigation reveals that these core users are not necessarily the large-degree users. Moreover, they tend to select high quality objects and their selections are well diversified.

  12. Leading Common Core Implementation

    ERIC Educational Resources Information Center

    Holliday, Terry; Smith, Felicia C.

    2012-01-01

    Kentucky is no stranger to education reform, having worked for the better part of 20 years on raising standards to improve student achievement. In 2009, the Kentucky General Assembly called for more rigorous standards to address high school graduates' college and career readiness. So when the National Governors Association and the Council of Chief…

  13. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor

    SciTech Connect

    Francesco Venneri; Chang-Keun Jo; Jae-Man Noh; Yonghee Kim; Claudio Filippone; Jonghwa Chang; Chris Hamilton; Young-Min Kim; Ji-Su Jun; Moon-Sung Cho; Hong-Sik Lim; MIchael A. Pope; Abderrafi M. Ougouag; Vincent Descotes; Brian Boer

    2010-09-01

    MWth DB-HTRs. The TRISO fuel microanalysis covers the gas pressure buildup in a coated fuel particle including helium production, the thermo-mechanical behavior of a CFP, the failure probabilities of CFPs, the temperature distribution in a CPF, and the fission product (FP) transport in a CFP and a graphite. In Chapter VIII, it contains the core design and analysis of sodium cooled fast reactor (SFR) with deep burn HTR reactor. It considers a synergistic combination of the DB-MHR and an SFR burner for a safe and efficient transmutation of the TRUs from LWRs. Chapter IX describes the design and analysis results of the self-cleaning (or self-recycling) HTR core. The analysis is considered zero and 5-year cooling time of the spent LWR fuels.

  14. Complicated Politics to the Core

    ERIC Educational Resources Information Center

    McGuinn, Patrick

    2015-01-01

    People dislike the Common Core for several different reasons, and so it is important to disaggregate the sources of opposition and to assess and then to dispel some of the myths that have built up around it. It also is important to understand the unusual political alliances that have emerged in opposition to Common Core implementation and how they…

  15. The Common Core Takes Hold

    ERIC Educational Resources Information Center

    Rothman, Robert

    2014-01-01

    A survey administered in the spring of 2013 by the Center on Education Policy (CEP) inquired into the implementation of Common Core State Standards at that time. Based on self-reports by state officials, the survey found that curricula aligned to the common core were already being taught in at least some districts or grade levels. All states…

  16. Common Core: Victory Is Yours!

    ERIC Educational Resources Information Center

    Fink, Jennifer L. W.

    2012-01-01

    In this article, the author discusses how to implement the Common Core State Standards in the classroom. She presents examples and activities that will leave teachers feeling "rosy" about tackling the new standards. She breaks down important benchmarks and shows how other teachers are doing the Core--and loving it!

  17. Understanding Common Core State Standards

    ERIC Educational Resources Information Center

    Kendall, John S.

    2011-01-01

    Now that the Common Core standards are coming to just about every school, what every school leader needs is a straightforward explanation that lays out the benefits of the Common Core in plain English, provides a succinct overview, and gets everyone thinking about how to transition to this promising new paradigm. This handy, inexpensive booklet…

  18. COVERING A CORE BY EXTRUSION

    DOEpatents

    Karnie, A.J.

    1963-07-16

    A method of covering a cylindrical fuel core with a cladding metal ms described. The metal is forced between dies around the core from both ends in two opposing skirts, and as these meet the ends turn outward into an annular recess in the dics. By cutting off the raised portion formed by the recess, oxide impurities are eliminated. (AEC)

  19. COOL CORE CLUSTERS FROM COSMOLOGICAL SIMULATIONS

    SciTech Connect

    Rasia, E.; Borgani, S.; Murante, G.; Planelles, S.; Biffi, V.; Granato, G. L.; Beck, A. M.; Steinborn, L. K.; Dolag, K.; Ragone-Figueroa, C.

    2015-11-01

    We present results obtained from a set of cosmological hydrodynamic simulations of galaxy clusters, aimed at comparing predictions with observational data on the diversity between cool-core (CC) and non-cool-core (NCC) clusters. Our simulations include the effects of stellar and active galactic nucleus (AGN) feedback and are based on an improved version of the smoothed particle hydrodynamics code GADGET-3, which ameliorates gas mixing and better captures gas-dynamical instabilities by including a suitable artificial thermal diffusion. In this Letter, we focus our analysis on the entropy profiles, the primary diagnostic we used to classify the degree of cool-coreness of clusters, and the iron profiles. In keeping with observations, our simulated clusters display a variety of behaviors in entropy profiles: they range from steadily decreasing profiles at small radii, characteristic of CC systems, to nearly flat core isentropic profiles, characteristic of NCC systems. Using observational criteria to distinguish between the two classes of objects, we find that they occur in similar proportions in both simulations and observations. Furthermore, we also find that simulated CC clusters have profiles of iron abundance that are steeper than those of NCC clusters, which is also in agreement with observational results. We show that the capability of our simulations to generate a realistic CC structure in the cluster population is due to AGN feedback and artificial thermal diffusion: their combined action allows us to naturally distribute the energy extracted from super-massive black holes and to compensate for the radiative losses of low-entropy gas with short cooling time residing in the cluster core.

  20. Growth of the inner core by snowfall

    NASA Astrophysics Data System (ADS)

    Lasbleis, M.; Labrosse, S.; Hernlund, J. W.

    2012-12-01

    In past decades, seismic studies of the Earth's core have tremendously improved our knowledge of its structure. The solid inner core presents heterogeneity at all scales, including both regional and hemispherical variations in degree and possibly orientation of elastic anisotropy, small-scale scattering, and potential indications of internal layering. Seismic observations also reveal subtle changes in seismic velocity gradient at the bottom of the liquid outer core that has been interpreted as a stratified layer, depleted in light alloying elements. Gubbins et al. (GJI, 2008) proposed that such a layer could be at the liquidus throughout, however, the details of the process that gives rise to such a scenario and its dynamical evolution with time have not been elucidated. Here we propose a model of slurry (snowfall) inside the F-layer. We have formulated a binary alloy model for the nucleation, settling and chemical reaction of snow with surrounding fluid in which cooling and crystallization is driven at the top of a compositionally stratified F-layer. Our model reveals a simple dynamical feedback that could drive the system toward a state such that the entire stratified region is maintained at the liquidus. We find that diffusion is the dominant transport phenomenon inside the layer, between the freely convecting outer core and the inner core, for both temperature and composition. Owing to variations in heat flow with time imposed by mantle convection, the equilibrium between the geotherm and liquidus in the F-layer would be perturbed, and we derive time scales for enhanced melting or freezing of snow to return the layer to equilibrium.

  1. Autism, will vitamin D treat core symptoms?

    PubMed

    Cannell, John Jacob

    2013-08-01

    No medication exists to treat the core symptoms of autism. However, some children spontaneously improve and have optimal outcomes. Parents of autistic children who have access to swimming pool have reported summertime improvement in symptoms to me. A Japanese case report found the same summer times improvements. If the cause of that summertime improvement could be identified, it may lead to effective treatment. Vitamin D is highly seasonal with a summertime surfeit and a wintertime deficit. The hypotheses that the increased prevalence in the diagnosis of autism is due to better detection imply that parents, teachers and physicians of the 1950s, 60s, and 70s missed this non subtle diagnosis, an unlikely scenario. Recent research indicates that autism often first present itself during the second and third year of life. This is a time when most toddlers have no known sources of vitamin D. Vitamin D has remarkable antioxidant, anti-inflammatory, and anti-autoimmune properties. In vitro, in vivo, and animal experiments provide compelling data for vitamin D's role brain proliferation, differentiation, neurotrophism, neuroprotection, neurotransmission, and neuroplasticity. It also upregulates glutathione, upregulates a suit of genes involved in DNA repair and raises the seizure threshold. Adequate, perhaps pharmacological, doses of vitamin D may have a treatment effect in the core symptoms of autism.

  2. Toward quantitative core-loss EFTEM tomography.

    PubMed

    Jin-Phillipp, N Y; Koch, C T; van Aken, P A

    2011-07-01

    Core-loss EFTEM tomography provides three-dimensional structural and chemical information. Multiple inelastic scattering occurring in thick specimens as well as orientation-dependent diffraction contrast due to multiple elastic scattering, however, often limit its applications. After demonstrating the capability of core-loss EFTEM tomography to reconstruct just a few monolayers thin carbon layer covering a Fe catalyst particle we discuss its application to thicker samples. We propose an approximate multiple-scattering correction method based on the use of zero-loss images and apply it successfully to copper whiskers, providing a significant improvement of the reconstructed 3D elemental distribution. We conclude this paper by a general discussion on experimental parameters affecting the accuracy of EFTEM 3D elemental mapping. PMID:21864765

  3. Anisotropic charged core envelope star

    NASA Astrophysics Data System (ADS)

    Mafa Takisa, P.; Maharaj, S. D.

    2016-08-01

    We study a charged compact object with anisotropic pressures in a core envelope setting. The equation of state is quadratic in the core and linear in the envelope. There is smooth matching between the three regions: the core, envelope and the Reissner-Nordström exterior. We show that the presence of the electric field affects the masses, radii and compactification factors of stellar objects with values which are in agreement with previous studies. We investigate in particular the effect of electric field on the physical features of the pulsar PSR J1614-2230 in the core envelope model. The gravitational potentials and the matter variables are well behaved within the stellar object. We demonstrate that the radius of the core and the envelope can vary by changing the parameters in the speed of sound.

  4. Low invasion fluids for pressuring coring. Final report. [Hydroxyethylcellulose polymer

    SciTech Connect

    Heckes, A.A.; McFall, A.L.

    1981-10-01

    A program has been completed to develop improved low invasion fluids for pressure coring applications. This paper describes the results of an experimental investigation which was performed on seven different low invasion fluids. The investigation employed commercially available calcium carbonate (CaCO/sub 3/) materials which were compared using two different sandstone core samples (brown and gray berea) and two simulated field conditions (static and dynamic). The results indicate that the presently used mixture of 10 lb/bbl hydroxyethyl cellulose (HEC) polymer and 300 lb/bbl CaCO/sub 3/ in a CaCl/sub 2/ eutectic brine mixture appears to be a very good choice for minimizing invasion of the core sample. Minor improvements in core invasion are achieved by matching the CaCo/sub 3/ particle size to the formation pore size. Experimentation or prior experience are necessary for choosing the type of CaCO/sub 3/ to be used. At best, the invasion of the core may only be slowed and not stopped completely. Factors which cause relatively large amounts of filtrate intrusion into the core are long exposure times, low fluid viscosities, and low solids content of the fluid. Curves demonstrating the effectiveness of high polymer and CaCO/sub 3/ particle concentrations and comparing the core invasion of water, bentonite drilling mud and the seven low invasion fluids are presented.

  5. Redox-Responsive, Core Cross-Linked Polyester Micelles

    PubMed Central

    Zhang, Zhonghai; Yin, Lichen; Tu, Chunlai; Song, Ziyuan; Zhang, Yanfeng; Xu, Yunxiang; Tong, Rong; Zhou, Qin; Ren, Jie; Cheng, Jianjun

    2013-01-01

    Monomethoxy poly(ethylene glycol)-b-poly(Tyr(alkynyl)-OCA), a biodegradable amphiphilic block copolymer, was synthesized by means of ring-opening polymerization of 5-(4-(prop-2-yn-1-yloxy)benzyl)-1,3-dioxolane-2,4-dione (Tyr(alkynyl)-OCA) and used to prepare core cross-linked polyester micelles via click chemistry. Core cross-linking not only improved the structural stability of the micelles but also allowed controlled release of cargo molecules in response to the reducing reagent. This new class of core cross-linked micelles can potentially be used in controlled release and drug delivery applications. PMID:23536920

  6. Core stability training on lower limb balance strength.

    PubMed

    Dello Iacono, Antonio; Padulo, Johnny; Ayalon, Moshe

    2016-01-01

    This study aimed to assess the effects of core stability training on lower limbs' muscular asymmetries and imbalances in team sport. Twenty footballers were divided into two groups, either core stability or control group. Before each daily practice, core stability group (n = 10) performed a core stability training programme, while control group (n = 10) did a standard warm-up. The effects of the core stability training programme were assessed by performing isokinetic tests and single-leg countermovement jumps. Significant improvement was found for knee extensors peak torque at 3.14 rad · s(-1) (14%; P < 0.05), knee flexors peak torque at 1.05 and 3.14 rad · s(-1) (19% and 22% with P < 0.01 and P < 0.01, respectively) and peak torque flexors/extensors ratios at 1.05 and 3.14 rad · s(-1) (7.7% and 8.5% with P < 0.05 and P < 0.05, respectively) only in the core stability group. The jump tests showed a significant reduction in the strength asymmetries in core stability group (-71.4%; P = 0.02) while a concurrent increase was seen in the control group (33.3%; P < 0.05). This study provides practical evidence in combining core exercises for optimal lower limbs strength balance development in young soccer players.

  7. Imaging the Moon's core with seismology

    NASA Astrophysics Data System (ADS)

    Weber, R. C.; Lin, P. P.; Garnero, E. J.; Williams, Q. C.; Lognonne, P.

    2011-12-01

    Constraining the structure of the lunar core is necessary to improve our understanding of the present-day thermal structure of the interior and the history of a lunar dynamo, as well as the origin and thermal and compositional evolution of the Moon. We analyze Apollo deep moonquake seismograms using terrestrial array processing methods to search for the presence of reflected and converted energy from the lunar core. Although moonquake fault parameters are not constrained, we first explore a suite of theoretical focal spheres to verify that fault planes exist that can produce favorable core reflection amplitudes relative to direct up-going energy at the Apollo stations. Beginning with stacks of event seismograms from the known distribution of deep moonquake clusters, we apply a polarization filter to account for the effects of seismic scattering that (a) partitions energy away from expected components of ground motion, and (b) obscures all but the main P- and S-wave arrivals. The filtered traces are then shifted to the predicted arrival time of a core phase (e.g. PcP) and stacked to enhance subtle arrivals associated with the Moon's core. This combination of filtering and array processing is well suited for detecting deep lunar seismic reflections, since we do not expect scattered wave energy from near surface (or deeper) structure recorded at varying epicentral distances and stations from varying moonquakes at varying depths to stack coherently. Our results indicate the presence of a solid inner and fluid outer core, overlain by a partial-melt-containing boundary layer (Table 1). These layers are consistently observed among stacks from four classes of reflections: P-to-P, S-to-P, P-to-S, and S-to-S, and are consistent with current indirect geophysical estimates of core and deep mantle properties, including mass, moment of inertia, lunar laser ranging, and electromagnetic induction. Future refinements are expected following the successful launch of the GRAIL lunar

  8. Imaging the Moon's Core with Seismology

    NASA Technical Reports Server (NTRS)

    Weber, Renee C.; Lin, Pei-Ying Patty; Garnero, Ed J.; Williams, Quetin C.; Lognonne, Philippe

    2011-01-01

    Constraining the structure of the lunar core is necessary to improve our understanding of the present-day thermal structure of the interior and the history of a lunar dynamo, as well as the origin and thermal and compositional evolution of the Moon. We analyze Apollo deep moonquake seismograms using terrestrial array processing methods to search for the presence of reflected and converted energy from the lunar core. Although moonquake fault parameters are not constrained, we first explore a suite of theoretical focal spheres to verify that fault planes exist that can produce favorable core reflection amplitudes relative to direct up-going energy at the Apollo stations. Beginning with stacks of event seismograms from the known distribution of deep moonquake clusters, we apply a polarization filter to account for the effects of seismic scattering that (a) partitions energy away from expected components of ground motion, and (b) obscures all but the main P- and S-wave arrivals. The filtered traces are then shifted to the predicted arrival time of a core phase (e.g. PcP) and stacked to enhance subtle arrivals associated with the Moon s core. This combination of filtering and array processing is well suited for detecting deep lunar seismic reflections, since we do not expect scattered wave energy from near surface (or deeper) structure recorded at varying epicentral distances and stations from varying moonquakes at varying depths to stack coherently. Our results indicate the presence of a solid inner and fluid outer core, overlain by a partial-melt-containing boundary layer (Table 1). These layers are consistently observed among stacks from four classes of reflections: P-to-P, S-to-P, P-to-S, and S-to-S, and are consistent with current indirect geophysical estimates of core and deep mantle properties, including mass, moment of inertia, lunar laser ranging, and electromagnetic induction. Future refinements are expected following the successful launch of the GRAIL lunar

  9. Radiation Effects: Core Project

    NASA Technical Reports Server (NTRS)

    Dicello, John F.

    1999-01-01

    The risks to personnel in space from the naturally occurring radiations are generally considered to be one of the most serious limitations to human space missions, as noted in two recent reports of the National Research Council/National Academy of Sciences. The Core Project of the Radiation Effects Team for the National Space Biomedical Research Institute is the consequences of radiations in space in order to develop countermeasure, both physical and pharmaceutical, to reduce the risks of cancer and other diseases associated with such exposures. During interplanetary missions, personnel in space will be exposed to galactic cosmic rays, including high-energy protons and energetic ions with atomic masses of iron or higher. In addition, solar events will produce radiation fields of high intensity for short but irregular durations. The level of intensity of these radiations is considerably higher than that on Earth's surface, and the biological risks to astronauts is consequently increased, including increased risks of carcinogenesis and other diseases. This group is examining the risk of cancers resulting from low-dose, low-dose rate exposures of model systems to photons, protons, and iron by using ground-based accelerators which are capable of producing beams of protons, iron, and other heavy ions at energies comparable to those encountered in space. They have begun the first series of experiments using a 1-GeV iron beam at the Brookhaven National Laboratory and 250-MeV protons at Loma Linda University Medical Center's proton synchrotron facility. As part of these studies, this group will be investigating the potential for the pharmaceutical, Tamoxifen, to reduce the risk of breast cancer in astronauts exposed to the level of doses and particle types expected in space. Theoretical studies are being carried out in a collaboration between scientists at NASA's Johnson Space Center and Johns Hopkins University in parallel with the experimental program have provided

  10. Evolution of First Cores and Formation of Stellar Cores in Rotating Molecular Cloud Cores

    NASA Astrophysics Data System (ADS)

    Saigo, Kazuya; Tomisaka, Kohji; Matsumoto, Tomoaki

    2008-02-01

    We followed the collapse of cloud cores with various rotation speed and density frustrations using three-dimensional hydrodynamical simulations by assuming a barotropic equation of state and examined the comprehensive evolution paths from the rotation molecule cloud core to stellar core. We found that the evolutionary paths depend only on the angular velocity of initial cloud core Ωc0. These evolutionary paths agree well with predictions of Saigo and Tomisaka's quasi-equilibrium axisymmetric models and SPH calculations of Bate. Evolutionary paths are qualitatively classified into three types. (1) A slowly rotating cloud with Ωc0 < 0.01/tff = 0.05(ρc0/10-19 g cm -3)1/2 rad Myr -1 shows spherical-type evolution, where ρc0 is the initial central density. Such a cloud forms a first core which is mainly supported by the thermal pressure. The first core has a small mass of Mcore ~ 0.01 M⊙ and a short lifetime of a few ×100 yr. After exceeding the H2 dissociation density ρ simeq 5.6 × 10-8 g cm -3, it begins the second collapse, and the whole of the first core accretes onto the stellar core/disk within a few free-fall timescales. (2) A rotating cloud with 0.01/tff < Ωc0lesssim 0.05/tff shows disk-type evolution. In this case, the first core becomes a centrifugally supported massive disk with Mcore ~ a few × 0.01-0.1 M⊙ and the lifetime is a few thousand years. The first core is unstable against nonaxisymmetric dynamic instability and forms spiral arms. The gravitational torque through spiral structure extracts angular momentum from the central region to the outer region of the first core. And only a central part with r ~ 1 AU begins the second collapse after exceeding dissociation density. However, the outer remnant disk keeps its centrifugal balance after stellar core formation. It seems that this remnant of the first core should control the mass and angular momentum accretion onto the newborn stellar system. (3) A rotating cloud with 0.05/tfflesssim Ωc0

  11. HOW STARLESS ARE STARLESS CORES?

    SciTech Connect

    Schnee, Scott; Friesen, Rachel; Di Francesco, James; Johnstone, Doug; Enoch, Melissa; Sadavoy, Sarah

    2012-01-20

    In this paper, we present the results of Combined Array for Research in Millimeter-wave Astronomy continuum and spectral line observations of the dense core Per-Bolo 45. Although this core has previously been classified as starless, we find evidence for an outflow and conclude that Per-Bolo 45 is actually an embedded, low-luminosity protostar. We discuss the impact of newly discovered, low-luminosity, embedded objects in the Perseus molecular cloud on starless core and protostar lifetimes. We estimate that the starless core lifetime has been overestimated by 4%-18% and the Class 0/I protostellar lifetime has been underestimated by 5%-20%. Given the relatively large systematic uncertainties involved in these calculations, variations on the order of 10% do not significantly change either core lifetimes or the expected protostellar luminosity function. Finally, we suggest that high-resolution (sub)millimeter surveys of known cores lacking near-infrared and mid-infrared emission are necessary to make an accurate census of starless cores.

  12. Bent core liquid crystal elastomers

    SciTech Connect

    Verduzco, R.; DiMasi, E.; Luchette, P.; Ho Hong, S.; Harden, J.; Palffy-Muhoray, P.; Kilbey II, S.M.; Sprunt, S.; Gleeson, G.T. Jakli, A.

    2010-07-28

    Liquid crystal (LC) elastomers with bent-core side-groups incorporate the properties of bent-core liquid crystals in a flexible and self-supporting polymer network. Bent-core liquid crystal elastomers (BCEs) with uniform alignment were prepared by attaching a reactive bent-core LC to poly(hydrogenmethylsiloxane) and crosslinking with a divinyl crosslinker. Phase behavior studies indicate a nematic phase over a wide temperature range that approaches room temperature, and thermoelastic measurements show that these BCEs can reversibly change their length by more than a factor of two upon heating and cooling. Small-angle X-ray scattering studies reveal multiple, broad low-angle peaks consistent with short-range smectic C order of the bent-core side groups. A comparison of these patterns with predictions of a Landau model for short-range smectic C order shows that the length scale for smectic ordering in BCEs is similar to that seen in pure bent-core LCs. The combination of rubber elasticity and smectic ordering of the bent-core side groups suggests that BCEs may be promising materials for sensing, actuating, and other advanced applications.

  13. Simplified cut core inductor design

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1974-01-01

    Although filter inductor designers have routinely tended to specify molypermalloy powder cores for use in high frequency power converters and pulse-width modulated switching regulators, there are sigificant advantages in specifying C cores and cut toroids fabricated from grain oriented silicon steels which should not be overlooked. Such steel cores can develop flux densities of 1.6 tesla, with useful linearity to 1.2 tesla, whereas molypermalloy cores carrying d.c. current have useful flux density capabilities only to about 0.3 tesla. The use of silicon steel cores thus makes it possible to design more compact cores, and therefore inductors of reduced volume, or conversely to provide greater load capacity in inductors of a given volume. Information is available which makes it possible to obtain quick and close approximations of significant parameters such as size, weight and temperature rise for silicon steel cores for breadboarding. Graphs, nomographs and tables are presented for this purpose, but more complete mathematical derivations of some of the important parameters are also included for a more rigorous treatment.

  14. Core physics analysis of 100% MOX Core in IRIS

    SciTech Connect

    Franceschini, F.; Petrovic, B.

    2006-07-01

    International Reactor Innovative and Secure (IRIS) is an advanced small-to-medium-size (1000 MWt) Pressurized Water Reactor (PWR), targeting deployment around 2015. Its reference core design is based on the current Westinghouse UO{sub 2} fuel with less than 5% {sup 235}U, and the analysis has been previously completed confirming good performance. The full MOX fuel core is currently under evaluation as one of the alternatives for the second wave of IRIS reactors. A full 3-D neutronic analysis has been performed to examine main core performance parameters, such as critical boron concentration, peaking factors, discharge burnup, etc. The enhanced moderation of the IRIS fuel lattice facilitates MOX core design, and all the obtained results are within the requirements, confirming viability of this option from the reactor physics standpoint. (authors)

  15. ASTRID sodium cooled fast reactor: Program for improving in service inspection and repair

    SciTech Connect

    Jadot, F.; De Dinechin, G.; Augem, J. M.; Sibilo, J.

    2011-07-01

    In the frame of the CEA, EDF, AREVA coordinated research program for the development of Generation IV sodium-cooled fast reactors (SFR), the ASTRID project was launched in 2010. For the future prototype, the improvement of in-service inspection and repair (ISI and R) capabilities was identified as a major issue. Following the pluri-annual SFR research program, the ISI and R main R and D axes remain: i) improvement of the primary system conceptual design, ii) development of measurement and inspection techniques (continuous monitoring instrumentation and periodic inspection tools), iii) accessibility and associated robotics, and iv) development and validation of repair processes. Associated ISI and R needs are being defined through an iterative method between designers and instrumentation specialists: adaptation of the Design to ISI and R requirements, fission chamber development, validation of the ultrasonic and chemical transducers, of ultrasonic non destructive simulation, of acoustic surveillance, of laser repair intervention processes, of connected robotic equipment. Moreover, CEA, as leader of the ASTRID Project, is willing to find new contributors, partners or suppliers, in order to get innovative, diversified, exhaustive and efficient solutions. (authors)

  16. Inner Core Structure Behind the PKP Core Phase Triplication

    NASA Astrophysics Data System (ADS)

    Blom, N.; Paulssen, H.; Deuss, A. F.; Waszek, L.

    2015-12-01

    Despite its small size, the Earth's inner core plays an important role in the Earth's dynamics. Because it is slowly growing, its structure - and the variation thereof with depth - may reveal important clues about the history of the core, its convection and the resulting geodynamo. Learning more about this structure has been a prime effort in the past decades, leading to discoveries about anisotropy, hemispheres and heterogeneity in the inner core in general. In terms of detailed structure, mainly seismic body waves have contributed to these advances. However, at depths between ~100-200 km, the seismic structure is relatively poorly known. This is a result of the PKP core phase triplication and the existence of strong precursors to PKP phases, whose simultaneous arrival hinders the measurement of inner core waves PKIKP at epicentral distances between roughly 143-148°. As a consequence, the interpretation of deeper structure also remains difficult. To overcome these issues, we stack seismograms in slowness and time, separating PKP and PKIKP phases which arrive simultaneously, but with different slowness. We apply this method to study the inner core's Western hemisphere between South and Central America using paths travelling in the quasi-polar direction between epicentral distances of 140-150°. This enables us to measure PKiKP-PKIKP differential travel times up to greater epicentral distance than has previously been done. The resulting differential travel time residuals increase with epicentral distance, indicating a marked increase in seismic velocity with depth compared to reference model AK135 for the studied polar paths. Assuming a homogeneous outer core, these findings can be explained by either (i) inner core heterogeneity due to an increase in isotropic velocity, or (ii) increase in anisotropy over the studied depth range. Our current data set cannot distinguish between the two hypotheses, but in light of previous work we prefer the latter interpretation.

  17. (Plasmonic Metal Core)/(Semiconductor Shell) Nanostructures

    NASA Astrophysics Data System (ADS)

    Fang, Caihong

    Over the past several years, integration of metal nanocrystals that can support localized surface plasmon has been demonstrated as one of the most promising methods to the improvement of the light-harvesting efficiency of semiconductors. Ag and Au nanocrystals have been extensively hybridized with semiconductors by either deposition or anchoring. However, metal nanocrystals tend to aggregate, reshape, detach, or grow into large nanocrystals, leading to a loss of the unique properties seen in the original nanocrystals. Fortunately, core/shell nanostructures, circumventing the aforementioned problems, have been demonstrated to exhibit superior photoactivities. To further improve the light-harvesting applications of (plasmonic metal core)/(semiconductor shell) nanostructures, it is vital to understand the plasmonic and structural evolutions during the preparation processes, design novel hybrid nanostructures, and improve their light-harvesting performances. In this thesis, I therefore studied the plasmonic and structural evolutions during the formation of (Ag core)/(Ag2S shell) nanostructures. Moreover, I also prepared (noble metal core)/(TiO2 shell) nanostructures and investigated their plasmonic properties and photon-harvesting applications. Clear understanding of the sulfidation process can enable fine control of the plasmonic properties as well as the structural composition of Ag/Ag 2S nanomaterials. Therefore, I investigated the plasmonic and structural variations during the sulfidation process of Ag nanocubes both experimentally and numerically. The sulfidation reactions were carried out at both the ensemble and single-particle levels. Electrodynamic simulations were also employed to study the variations of the plasmonic properties and plasmon modes. Both experiment and simulation results revealed that sulfidation initiates at the vertices of Ag nanocubes. Ag nanocubes are then gradually truncated and each nanocube becomes a nanosphere eventually. The cubic

  18. Uranium droplet core nuclear rocket

    NASA Technical Reports Server (NTRS)

    Anghaie, Samim

    1991-01-01

    Uranium droplet nuclear rocket is conceptually designed to utilize the broad temperature range ofthe liquid phase of metallic uranium in droplet configuration which maximizes the energy transfer area per unit fuel volume. In a baseline system dissociated hydrogen at 100 bar is heated to 6000 K, providing 2000 second of Isp. Fission fragments and intense radian field enhance the dissociation of molecular hydrogen beyond the equilibrium thermodynamic level. Uranium droplets in the core are confined and separated by an axisymmetric vortex flow generated by high velocity tangential injection of hydrogen in the mid-core regions. Droplet uranium flow to the core is controlled and adjusted by a twin flow nozzle injection system.

  19. Characterizing Facesheet/Core Disbonding in Honeycomb Core Sandwich Structure

    NASA Technical Reports Server (NTRS)

    Rinker, Martin; Ratcliffe, James G.; Adams, Daniel O.; Krueger, Ronald

    2013-01-01

    Results are presented from an experimental investigation into facesheet core disbonding in carbon fiber reinforced plastic/Nomex honeycomb sandwich structures using a Single Cantilever Beam test. Specimens with three, six and twelve-ply facesheets were tested. Specimens with different honeycomb cores consisting of four different cell sizes were also tested, in addition to specimens with three different widths. Three different data reduction methods were employed for computing apparent fracture toughness values from the test data, namely an area method, a compliance calibration technique and a modified beam theory method. The compliance calibration and modified beam theory approaches yielded comparable apparent fracture toughness values, which were generally lower than those computed using the area method. Disbonding in the three-ply facesheet specimens took place at the facesheet/core interface and yielded the lowest apparent fracture toughness values. Disbonding in the six and twelve-ply facesheet specimens took place within the core, near to the facesheet/core interface. Specimen width was not found to have a significant effect on apparent fracture toughness. The amount of scatter in the apparent fracture toughness data was found to increase with honeycomb core cell size.

  20. High-burnup core design using minor actinide-containing metal fuel

    SciTech Connect

    Ohta, Hirokazu; Ogata, Takanari; Obara, T.

    2013-07-01

    A neutronic design study of metal fuel fast reactor (FR) cores is conducted on the basis of an innovative fuel design concept to achieve an extremely high burnup and realize an efficient fuel cycle system. Since it is expected that the burnup reactivity swing will become extremely large in an unprecedented high burnup core, minor actinides (MAs) from light water reactors (LWRs) are added to fresh fuel to improve the core internal conversion. Core neutronic analysis revealed that high burnups of about 200 MWd/kg for a small-scale core and about 300 MWd/kg for a large-scale core can be attained while suppressing the burnup reactivity swing to almost the same level as that of conventional cores with normal burnup. An actinide burnup analysis has shown that the MA consumption ratio is improved to about 60% and that the accumulated MAs originating from LWRs can be efficiently consumed by the high-burnup metal fuel FR. (authors)

  1. Magnetic core mounting system

    DOEpatents

    Ronning, Jeffrey J.

    2002-01-01

    A mounting apparatus for an electromagnetic device such as a transformer of inductor includes a generally planar metallic plate as a first heat sink, and a metallic mounting cup as a second heat sink. The mounting cup includes a cavity configured to receive the electromagnetic device, the cavity being defined by a base, and an axially-extending annular sidewall extending from the base to a flange portion of the mounting cup. The mounting cup includes first and second passages for allowing the leads of first and second windings of the electromagnetic device to be routed out of the cavity. The cavity is filled with a polyurethane potting resin, and the mounting cup, including the potted electromagnetic device, is mounted to the plate heat sink using fasteners. The mounting cup, which surrounds the electromagnetic device, in combination with the potting resin provides improved thermal transfer to the plate heat sink, as well as providing resistance to vibration and shocks.

  2. Convection, nucleosynthesis, and core collapse

    NASA Technical Reports Server (NTRS)

    Bazan, Grant; Arnett, David

    1994-01-01

    We use a piecewise parabolic method hydrodynamics code (PROMETHEUS) to study convective burning in two dimensions in an oxygen shell prior to core collapse. Significant mixing beyond convective boundaries determined by mixing-length theory brings fuel (C-12) into the convective regon, causing hot spots of nuclear burning. Plumes dominate the velocity structure. Finite perturbations arise in a region in which O-16 will be explosively burned to Ni-56 when the star explodes; the resulting instabilities and mixing are likely to distribute Ni-56 throughout the supernova envelope. Inhomogeneities in Y(sub e) may be large enough to affect core collapse and will affect explosive nucleosynthesis. The nature of convective burning is dramatically different from that assumed in one-dimensional simulations; quantitative estimates of nucleosynthetic yields, core masses, and the approach to core collapse will be affected.

  3. The ADNI PET Core: 2015

    PubMed Central

    Jagust, William J.; Landau, Susan M.; Koeppe, Robert A.; Reiman, Eric M.; Chen, Kewei; Mathis, Chester A.; Price, Julie C.; Foster, Norman L.; Wang, Angela Y.

    2015-01-01

    INTRODUCTION This paper reviews the work done in the ADNI PET core over the past 5 years, largely concerning techniques, methods, and results related to amyloid imaging in ADNI. METHODS The PET Core has utilized [18F]florbetapir routinely on ADNI participants, with over 1600 scans available for download. Four different laboratories are involved in data analysis, and have examined factors such as longitudinal florbetapir analysis, use of FDG-PET in clinical trials, and relationships between different biomarkers and cognition. RESULTS Converging evidence from the PET Core has indicated that cross-sectional and longitudinal florbetapir analyses require different reference regions. Studies have also examined the relationship between florbetapir data obtained immediately after injection, which reflects perfusion, and FDG-PET results. Finally, standardization has included the translation of florbetapir PET data to a centiloid scale. CONCLUSION The PET Core has demonstrated a variety of methods for standardization of biomarkers such as florbetapir PET in a multicenter setting. PMID:26194311

  4. Metrics for Success: Strategies for Enabling Core Facility Performance and Assessing Outcomes

    PubMed Central

    Hockberger, Philip E.; Meyn, Susan M.; Nicklin, Connie; Tabarini, Diane; Auger, Julie A.

    2016-01-01

    Core Facilities are key elements in the research portfolio of academic and private research institutions. Administrators overseeing core facilities (core administrators) require assessment tools for evaluating the need and effectiveness of these facilities at their institutions. This article discusses ways to promote best practices in core facilities as well as ways to evaluate their performance across 8 of the following categories: general management, research and technical staff, financial management, customer base and satisfaction, resource management, communications, institutional impact, and strategic planning. For each category, we provide lessons learned that we believe contribute to the effective and efficient overall management of core facilities. If done well, we believe that encouraging best practices and evaluating performance in core facilities will demonstrate and reinforce the importance of core facilities in the research and educational mission of institutions. It will also increase job satisfaction of those working in core facilities and improve the likelihood of sustainability of both facilities and personnel. PMID:26848284

  5. Metrics for Success: Strategies for Enabling Core Facility Performance and Assessing Outcomes.

    PubMed

    Turpen, Paula B; Hockberger, Philip E; Meyn, Susan M; Nicklin, Connie; Tabarini, Diane; Auger, Julie A

    2016-04-01

    Core Facilities are key elements in the research portfolio of academic and private research institutions. Administrators overseeing core facilities (core administrators) require assessment tools for evaluating the need and effectiveness of these facilities at their institutions. This article discusses ways to promote best practices in core facilities as well as ways to evaluate their performance across 8 of the following categories: general management, research and technical staff, financial management, customer base and satisfaction, resource management, communications, institutional impact, and strategic planning. For each category, we provide lessons learned that we believe contribute to the effective and efficient overall management of core facilities. If done well, we believe that encouraging best practices and evaluating performance in core facilities will demonstrate and reinforce the importance of core facilities in the research and educational mission of institutions. It will also increase job satisfaction of those working in core facilities and improve the likelihood of sustainability of both facilities and personnel.

  6. Metrics for Success: Strategies for Enabling Core Facility Performance and Assessing Outcomes.

    PubMed

    Turpen, Paula B; Hockberger, Philip E; Meyn, Susan M; Nicklin, Connie; Tabarini, Diane; Auger, Julie A

    2016-04-01

    Core Facilities are key elements in the research portfolio of academic and private research institutions. Administrators overseeing core facilities (core administrators) require assessment tools for evaluating the need and effectiveness of these facilities at their institutions. This article discusses ways to promote best practices in core facilities as well as ways to evaluate their performance across 8 of the following categories: general management, research and technical staff, financial management, customer base and satisfaction, resource management, communications, institutional impact, and strategic planning. For each category, we provide lessons learned that we believe contribute to the effective and efficient overall management of core facilities. If done well, we believe that encouraging best practices and evaluating performance in core facilities will demonstrate and reinforce the importance of core facilities in the research and educational mission of institutions. It will also increase job satisfaction of those working in core facilities and improve the likelihood of sustainability of both facilities and personnel. PMID:26848284

  7. Essential ingredients in core-collapse supernovae

    SciTech Connect

    Hix, W. Raphael; Lentz, Eric J.; Chertkow, M. Austin; Harris, J. Austin; Endeve, Eirik; Baird, Mark; Messer, O. E. Bronson; Mezzacappa, Anthony; Bruenn, Stephen; Blondin, John

    2014-04-15

    Carrying 10{sup 44} joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  8. Essential Ingredients in Core-collapse Supernovae

    SciTech Connect

    Hix, William Raphael; Lentz, E. J.; Endeve, Eirik; Baird, Mark L.; Chertkow, Merek A.; Harris, James A.; Messer, Bronson; Mezzacappa, Anthony; Bruenn, S. W.; Blondin, J. M.

    2014-03-27

    Marking the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae bring together physics at a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer scale nuclear reactions. Carrying 10$^{44}$ joules of kinetic energy and a rich-mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up ourselves and our solar system. We will discuss our emerging understanding of the convectively unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino-radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Recent multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of how supernovae explode. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  9. Essential Ingredients in Core-collapse Supernovae

    DOE PAGES

    Hix, William Raphael; Lentz, E. J.; Endeve, Eirik; Baird, Mark L.; Chertkow, Merek A.; Harris, James A.; Messer, Bronson; Mezzacappa, Anthony; Bruenn, S. W.; Blondin, J. M.

    2014-03-27

    Marking the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae bring together physics at a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer scale nuclear reactions. Carrying 10more » $$^{44}$$ joules of kinetic energy and a rich-mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up ourselves and our solar system. We will discuss our emerging understanding of the convectively unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino-radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Recent multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of how supernovae explode. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.« less

  10. Essential ingredients in core-collapse supernovae

    NASA Astrophysics Data System (ADS)

    Hix, W. Raphael; Lentz, Eric J.; Endeve, Eirik; Baird, Mark; Chertkow, M. Austin; Harris, J. Austin; Messer, O. E. Bronson; Mezzacappa, Anthony; Bruenn, Stephen; Blondin, John

    2014-04-01

    Carrying 1044 joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  11. Viscosity of the earth's core.

    NASA Technical Reports Server (NTRS)

    Gans, R. F.

    1972-01-01

    Calculation of the viscosity of the core at the boundary of the inner and outer core. It is assumed that this boundary is a melting transition and the viscosity limits of the Andrade (1934,1952) hypothesis (3.7 to 18.5 cp) are adopted. The corresponding kinematic viscosities are such that the precessional system explored by Malkus (1968) would be unstable. Whether it would be sufficiently unstable to overcome a severely subadiabatic temperature gradient cannot be determined.

  12. Lunar magnetism. [primordial core model

    NASA Technical Reports Server (NTRS)

    Goldstein, M. L.

    1975-01-01

    It is shown, for a very simple model of the moon, that the existence of a primordial core magnetic field would give rise to a present day nonzero dipole external field. In the investigation a uniformly magnetized core embedded in a permeable mantle is considered. The significance of the obtained results for the conclusions reported by Runcorn (1975) is discussed. Comments provided by Runcorn to the discussion are also presented.

  13. Vortex Core Size in the Rotor Near-Wake

    NASA Technical Reports Server (NTRS)

    Young, Larry A.

    2003-01-01

    Using a kinetic energy conservation approach, a number of simple analytic expressions are derived for estimating the core size of tip vortices in the near-wake of rotors in hover and axial-flow flight. The influence of thrust, induced power losses, advance ratio, and vortex structure on rotor vortex core size is assessed. Experimental data from the literature is compared to the analytical results derived in this paper. In general, three conclusions can be drawn from the work in this paper. First, the greater the rotor thrust, t h e larger the vortex core size in the rotor near-wake. Second, the more efficient a rotor is with respect to induced power losses, the smaller the resulting vortex core size. Third, and lastly, vortex core size initially decreases for low axial-flow advance ratios, but for large advance ratios core size asymptotically increases to a nominal upper limit. Insights gained from this work should enable improved modeling of rotary-wing aerodynamics, as well as provide a framework for improved experimental investigations of rotor a n d advanced propeller wakes.

  14. Advanced reactor physics methods for heterogeneous reactor cores

    NASA Astrophysics Data System (ADS)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

  15. A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey

    NASA Astrophysics Data System (ADS)

    Könyves, V.; André, Ph.; Men'shchikov, A.; Palmeirim, P.; Arzoumanian, D.; Schneider, N.; Roy, A.; Didelon, P.; Maury, A.; Shimajiri, Y.; Di Francesco, J.; Bontemps, S.; Peretto, N.; Benedettini, M.; Bernard, J.-Ph.; Elia, D.; Griffin, M. J.; Hill, T.; Kirk, J.; Ladjelate, B.; Marsh, K.; Martin, P. G.; Motte, F.; Nguyên Luong, Q.; Pezzuto, S.; Roussel, H.; Rygl, K. L. J.; Sadavoy, S. I.; Schisano, E.; Spinoglio, L.; Ward-Thompson, D.; White, G. J.

    2015-12-01

    gravitational fragmentation of marginally supercritical filaments. Given that filaments appear to dominate the mass budget of dense gas at AV> 7, our findings also suggest that the physics of prestellar core formation within filaments is responsible for a characteristic "efficiency" {SFR/M_dense ˜ 5+2-2 × 10-8 yr-1} for the star formation process in dense gas. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Figures 18, 19, and Appendices are available in electronic form at http://www.aanda.orgHerschel column density and temperature maps (FITS format) and full Tables A.1 and A.2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/584/A91

  16. Side polished twin-core fiber coupler

    NASA Astrophysics Data System (ADS)

    Wang, Xianbin; Yuan, Libo

    2015-07-01

    A novel optical fiber coupler was proposed and fabricated for coupling each core of a twin-core fiber (TCF) with a single-core fiber (SCF) core simultaneously and accessing independently both cores of the TCF. The coupler is mainly composed of two sides polished SCF and a side polished TCF. Each optical field launched from the TCF could be coupled into the side polished SCF. The coupler has a simple structure and less cross-talk between the two cores.

  17. Hollow-core photonic-crystal fibres for laser dentistry

    NASA Astrophysics Data System (ADS)

    Konorov, Stanislav O.; Mitrokhin, Vladimir P.; Fedotov, Andrei B.; Sidorov-Biryukov, Dmitrii A.; Beloglazov, Valentin I.; Skibina, Nina B.; Wintner, Ernst; Scalora, Michael; Zheltikov, Aleksei M.

    2004-04-01

    Hollow-core photonic-crystal fibres (PCFs) for the delivery of high-fluence laser radiation capable of ablating tooth enamel are developed. Sequences of picosecond pulses of 1.06 µm Nd:YAG-laser radiation with a total energy of about 2 mJ are transmitted through a hollow-core photonic-crystal fibre with a core diameter of approximately 14 µm and are focused on a tooth surface in vitro to ablate dental tissue. The hollow-core PCF is shown to support the single-fundamental-mode regime for 1.06 µm laser radiation, serving as a spatial filter and allowing the laser beam quality to be substantially improved. The same fibre is used to transmit emission from plasmas produced by laser pulses on the tooth surface in the backward direction for detection and optical diagnostics.

  18. Visual indication of mechanical damage using core-shell microcapsules.

    PubMed

    Odom, Susan A; Jackson, Aaron C; Prokup, Alex M; Chayanupatkul, Sarut; Sottos, Nancy R; White, Scott R; Moore, Jeffrey S

    2011-12-01

    We report a new core-shell microcapsule system for the visual detection of mechanical damage. The core material, 1,3,5,7-cyclooctatetraene, is a conjugated cyclic olefin and a precursor to intensely colored polyacetylene. A combination of poly(urea-formaldehyde) and polyurethane is required to effectively encapsulate the volatile core material. Increasing the outer shell wall thickness and including a core-side prepolymer improves the thermal stability and free-flowing nature of these capsules, which tend to leach and rupture with thinner shell walls. Capsules ruptured in the presence of the Grubbs-Love ruthenium catalyst show immediate color change from nearly colorless to red-orange and dark purple over time, and color change in thin films resulted from scratch damage. PMID:22114767

  19. Core-shell Au@Pd nanoparticles with enhanced catalytic activity for oxygen reduction reaction via core-shell Au@Ag/Pd constructions

    PubMed Central

    Chen, Dong; Li, Chengyin; Liu, Hui; Ye, Feng; Yang, Jun

    2015-01-01

    Core-shell nanoparticles often exhibit improved catalytic properties due to the lattice strain created in these core-shell particles. Herein, we demonstrate the synthesis of core-shell Au@Pd nanoparticles from their core-shell Au@Ag/Pd parents. This strategy begins with the preparation of core-shell Au@Ag nanoparticles in an organic solvent. Then, the pure Ag shells are converted into the shells made of Ag/Pd alloy by galvanic replacement reaction between the Ag shells and Pd2+ precursors. Subsequently, the Ag component is removed from the alloy shell using saturated NaCl solution to form core-shell Au@Pd nanoparticles with an Au core and a Pd shell. In comparison with the core-shell Au@Pd nanoparticles upon directly depositing Pd shell on the Au seeds and commercial Pd/C catalysts, the core-shell Au@Pd nanoparticles via their core-shell Au@Ag/Pd templates display superior activity and durability in catalyzing oxygen reduction reaction, mainly due to the larger lattice tensile effect in Pd shell induced by the Au core and Ag removal. PMID:26144550

  20. Core and Off-Core Processes in Systems Engineering

    NASA Technical Reports Server (NTRS)

    Breidenthal, Julian; Forsberg, Kevin

    2010-01-01

    An emerging methodology of organizing systems-engineering plans is based on a concept of core and off-core processes or activities. This concept has emerged as a result of recognition of a risk in the traditional representation of systems-engineering plans by a Vee model alone, according to which a large system is decomposed into levels of smaller subsystems, then integrated through levels of increasing scope until the full system is constructed. Actual systems-engineering activity is more complicated, raising the possibility that the staff will become confused in the absence of plans which explain the nature and ordering of work beyond the traditional Vee model.

  1. Core formation in silicate bodies

    NASA Astrophysics Data System (ADS)

    Nimmo, F.; O'Brien, D. P.; Kleine, T.

    2008-12-01

    Differentiation of a body into a metallic core and silicate mantle occurs most efficiently if temperatures are high enough to allow at least the metal to melt [1], and is enhanced if matrix deformation occurs [2]. Elevated temperatures may occur due to either decay of short-lived radio-isotopes, or gravitational energy release during accretion [3]. For bodies smaller than the Moon, core formation happens primarily due to radioactive decay. The Hf-W isotopic system may be used to date core formation; cores in some iron meteorites and the eucrite parent body (probably Vesta) formed within 1 My and 1-4~My of solar system formation, respectively [4]. These formation times are early enough to ensure widespread melting and differentiation by 26Al decay. Incorporation of Fe60 into the core, together with rapid early mantle solidification and cooling, may have driven early dynamo activity on some bodies [5]. Iron meteorites are typically depleted in sulphur relative to chondrites, for unknown reasons [6]. This depletion contrasts with the apparently higher sulphur contents of cores in larger planetary bodies, such as Mars [7], and also has a significant effect on the timing of core solidification. For bodies of Moon-size and larger, gravitational energy released during accretion is probably the primary cause of core formation [3]. The final stages of accretion involve large, stochastic collisions [8] between objects which are already differentiated. During each collision, the metallic cores of the colliding objects merge on timescales of a few hours [9]. Each collision will reset the Hf-W isotopic signature of both mantle and core, depending on the degree to which the impactor core re-equilibrates with the mantle of the target [10]. The re-equilibration efficiency depends mainly on the degree to which the impactor emulsifies [11], which is very uncertain. Results from N-body simulations [8,12] suggest that significant degrees of re- equilibration are required [4,10]. Re

  2. Core stability training: applications to sports conditioning programs.

    PubMed

    Willardson, Jeffrey M

    2007-08-01

    In recent years, fitness practitioners have increasingly recommended core stability exercises in sports conditioning programs. Greater core stability may benefit sports performance by providing a foundation for greater force production in the upper and lower extremities. Traditional resistance exercises have been modified to emphasize core stability. Such modifications have included performing exercises on unstable rather than stable surfaces, performing exercises while standing rather than seated, performing exercises with free weights rather than machines, and performing exercises unilaterally rather than bilaterally. Despite the popularity of core stability training, relatively little scientific research has been conducted to demonstrate the benefits for healthy athletes. Therefore, the purpose of this review was to critically examine core stability training and other issues related to this topic to determine useful applications for sports conditioning programs. Based on the current literature, prescription of core stability exercises should vary based on the phase of training and the health status of the athlete. During preseason and in-season mesocycles, free weight exercises performed while standing on a stable surface are recommended for increases in core strength and power. Free weight exercises performed in this manner are specific to the core stability requirements of sports-related skills due to moderate levels of instability and high levels of force production. Conversely, during postseason and off-season mesocycles, Swiss ball exercises involving isometric muscle actions, small loads, and long tension times are recommended for increases in core endurance. Furthermore, balance board and stability disc exercises, performed in conjunction with plyometric exercises, are recommended to improve proprioceptive and reactive capabilities, which may reduce the likelihood of lower extremity injuries.

  3. De novo design of the hydrophobic core of ubiquitin.

    PubMed Central

    Lazar, G. A.; Desjarlais, J. R.; Handel, T. M.

    1997-01-01

    We have previously reported the development and evaluation of a computational program to assist in the design of hydrophobic cores of proteins. In an effort to investigate the role of core packing in protein structure, we have used this program, referred to as Repacking of Cores (ROC), to design several variants of the protein ubiquitin. Nine ubiquitin variants containing from three to eight hydrophobic core mutations were constructed, purified, and characterized in terms of their stability and their ability to adopt a uniquely folded native-like conformation. In general, designed ubiquitin variants are more stable than control variants in which the hydrophobic core was chosen randomly. However, in contrast to previous results with 434 cro, all designs are destabilized relative to the wild-type (WT) protein. This raises the possibility that beta-sheet structures have more stringent packing requirements than alpha-helical proteins. A more striking observation is that all variants, including random controls, adopt fairly well-defined conformations, regardless of their stability. This result supports conclusions from the cro studies that non-core residues contribute significantly to the conformational uniqueness of these proteins while core packing largely affects protein stability and has less impact on the nature or uniqueness of the fold. Concurrent with the above work, we used stability data on the nine ubiquitin variants to evaluate and improve the predictive ability of our core packing algorithm. Additional versions of the program were generated that differ in potential function parameters and sampling of side chain conformers. Reasonable correlations between experimental and predicted stabilities suggest the program will be useful in future studies to design variants with stabilities closer to that of the native protein. Taken together, the present study provides further clarification of the role of specific packing interactions in protein structure and

  4. Core break-off mechanism

    NASA Technical Reports Server (NTRS)

    Myrick, Thomas M. (Inventor)

    2003-01-01

    A mechanism for breaking off and retaining a core sample of a drill drilled into a ground substrate has an outer drill tube and an inner core break-off tube sleeved inside the drill tube. The break-off tube breaks off and retains the core sample by a varying geometric relationship of inner and outer diameters with the drill tube. The inside diameter (ID) of the drill tube is offset by a given amount with respect to its outer diameter (OD). Similarly, the outside diameter (OD) of the break-off tube is offset by the same amount with respect to its inner diameter (ID). When the break-off tube and drill tube are in one rotational alignment, the two offsets cancel each other such that the drill can operate the two tubes together in alignment with the drill axis. When the tubes are rotated 180 degrees to another positional alignment, the two offsets add together causing the core sample in the break-off tube to be displaced from the drill axis and applying shear forces to break off the core sample.

  5. Integrating Medication Therapy Management Education into a Core Pharmacy Curriculum.

    PubMed

    Poole, Traci M; Kodali, Leela; Pace, Adam C

    2016-05-25

    Objective. To describe the design of a core course directed at improving confidence and competence of students to perform medication therapy management (MTM) services. Design. Using the American Pharmacists Association (APhA) certificate training program framework, a core course was developed to teach MTM concepts to third-year student pharmacists. Using deep learning and authentic assignments, course instructors attempted to improve student confidence and readiness to provide MTM services. Assessment. Student ability to meet course objectives was evaluated by examinations and the APhA MTM program self-assessment. Students had an overall success rate of 93% on all three assessments. Student perceptions of confidence, competence, and importance of performing MTM services were measured using a survey instrument with 56 Likert-type items. Students completing both surveys reported significantly increased confidence and competence. Conclusion. Integrating MTM-specific education into the core curriculum increased student pharmacists' perceived competence and confidence to perform MTM services. PMID:27293237

  6. Integrating Medication Therapy Management Education into a Core Pharmacy Curriculum

    PubMed Central

    Kodali, Leela; Pace, Adam C.

    2016-01-01

    Objective. To describe the design of a core course directed at improving confidence and competence of students to perform medication therapy management (MTM) services. Design. Using the American Pharmacists Association (APhA) certificate training program framework, a core course was developed to teach MTM concepts to third-year student pharmacists. Using deep learning and authentic assignments, course instructors attempted to improve student confidence and readiness to provide MTM services. Assessment. Student ability to meet course objectives was evaluated by examinations and the APhA MTM program self-assessment. Students had an overall success rate of 93% on all three assessments. Student perceptions of confidence, competence, and importance of performing MTM services were measured using a survey instrument with 56 Likert-type items. Students completing both surveys reported significantly increased confidence and competence. Conclusion. Integrating MTM-specific education into the core curriculum increased student pharmacists’ perceived competence and confidence to perform MTM services. PMID:27293237

  7. Grain Alignment in Starless Cores

    NASA Astrophysics Data System (ADS)

    Jones, T. J.; Bagley, M.; Krejny, M.; Andersson, B.-G.; Bastien, P.

    2015-01-01

    We present near-IR polarimetry data of background stars shining through a selection of starless cores taken in the K band, probing visual extinctions up to {{A}V}˜ 48. We find that {{P}K}/{{τ }K} continues to decline with increasing AV with a power law slope of roughly -0.5. Examination of published submillimeter (submm) polarimetry of starless cores suggests that by {{A}V}≳ 20 the slope for P versus τ becomes ˜-1, indicating no grain alignment at greater optical depths. Combining these two data sets, we find good evidence that, in the absence of a central illuminating source, the dust grains in dense molecular cloud cores with no internal radiation source cease to become aligned with the local magnetic field at optical depths greater than {{A}V}˜ 20. A simple model relating the alignment efficiency to the optical depth into the cloud reproduces the observations well.

  8. Foam Core Shielding for Spacecraft

    NASA Technical Reports Server (NTRS)

    Adams, Marc

    2007-01-01

    A foam core shield (FCS) system is now being developed to supplant multilayer insulation (MLI) systems heretofore installed on spacecraft for thermal management and protection against meteoroid impacts. A typical FCS system consists of a core sandwiched between a face sheet and a back sheet. The core can consist of any of a variety of low-to-medium-density polymeric or inorganic foams chosen to satisfy application-specific requirements regarding heat transfer and temperature. The face sheet serves to shock and thereby shatter incident meteoroids, and is coated on its outer surface to optimize its absorptance and emittance for regulation of temperature. The back sheet can be dimpled to minimize undesired thermal contact with the underlying spacecraft component and can be metallized on the surface facing the component to optimize its absorptance and emittance. The FCS systems can perform better than do MLI systems, at lower mass and lower cost and with greater volumetric efficiency.

  9. Reactor core isolation cooling system

    DOEpatents

    Cooke, F.E.

    1992-12-08

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom. 1 figure.

  10. Reactor core isolation cooling system

    DOEpatents

    Cooke, Franklin E.

    1992-01-01

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom.

  11. Apollo rocks, fines and soil cores

    NASA Astrophysics Data System (ADS)

    Allton, J.; Bevill, T.

    Apollo rocks and soils not only established basic lunar properties and ground truth for global remote sensing, they also provided important lessons for planetary protection (Adv. Space Res ., 1998, v. 22, no. 3 pp. 373-382). The six Apollo missions returned 2196 samples weighing 381.7 kg, comprised of rocks, fines, soil cores and 2 gas samples. By examining which samples were allocated for scientific investigations, information was obtained on usefulness of sampling strategy, sampling devices and containers, sample types and diversity, and on size of sample needed by various disciplines. Diversity was increased by using rakes to gather small rocks on the Moon and by removing fragments >1 mm from soils by sieving in the laboratory. Breccias and soil cores are diverse internally. Per unit weight these samples were more often allocated for research. Apollo investigators became adept at wringing information from very small sample sizes. By pushing the analytical limits, the main concern was adequate size for representative sampling. Typical allocations for trace element analyses were 750 mg for rocks, 300 mg for fines and 70 mg for core subsamples. Age-dating and isotope systematics allocations were typically 1 g for rocks and fines, but only 10% of that amount for core depth subsamples. Historically, allocations for organics and microbiology were 4 g (10% for cores). Modern allocations for biomarker detection are 100mg. Other disciplines supported have been cosmogenic nuclides, rock and soil petrology, sedimentary volatiles, reflectance, magnetics, and biohazard studies . Highly applicable to future sample return missions was the Apollo experience with organic contamination, estimated to be from 1 to 5 ng/g sample for Apollo 11 (Simonheit &Flory, 1970; Apollo 11, 12 &13 Organic contamination Monitoring History, U.C. Berkeley; Burlingame et al., 1970, Apollo 11 LSC , pp. 1779-1792). Eleven sources of contaminants, of which 7 are applicable to robotic missions, were

  12. Identifying ELIXIR Core Data Resources

    PubMed Central

    Durinx, Christine; McEntyre, Jo; Appel, Ron; Apweiler, Rolf; Barlow, Mary; Blomberg, Niklas; Cook, Chuck; Gasteiger, Elisabeth; Kim, Jee-Hyub; Lopez, Rodrigo; Redaschi, Nicole; Stockinger, Heinz; Teixeira, Daniel; Valencia, Alfonso

    2016-01-01

    The core mission of ELIXIR is to build a stable and sustainable infrastructure for biological information across Europe. At the heart of this are the data resources, tools and services that ELIXIR offers to the life-sciences community, providing stable and sustainable access to biological data. ELIXIR aims to ensure that these resources are available long-term and that the life-cycles of these resources are managed such that they support the scientific needs of the life-sciences, including biological research. ELIXIR Core Data Resources are defined as a set of European data resources that are of fundamental importance to the wider life-science community and the long-term preservation of biological data. They are complete collections of generic value to life-science, are considered an authority in their field with respect to one or more characteristics, and show high levels of scientific quality and service. Thus, ELIXIR Core Data Resources are of wide applicability and usage. This paper describes the structures, governance and processes that support the identification and evaluation of ELIXIR Core Data Resources. It identifies key indicators which reflect the essence of the definition of an ELIXIR Core Data Resource and support the promotion of excellence in resource development and operation. It describes the specific indicators in more detail and explains their application within ELIXIR’s sustainability strategy and science policy actions, and in capacity building, life-cycle management and technical actions. Establishing the portfolio of ELIXIR Core Data Resources and ELIXIR Services is a key priority for ELIXIR and publicly marks the transition towards a cohesive infrastructure. PMID:27803796

  13. Perspectives: The Continuous Improvement Trap

    ERIC Educational Resources Information Center

    Arnold, David L.

    2011-01-01

    Accrediting agencies, legislators, pundits, and even higher educational professionals have become enamored with applying the language of continuous improvement to learning outcomes. The Southern Association of Colleges and Schools Commission on Colleges specifically uses the term "continuing improvement" in Core Standard 2.5, one of its…

  14. The IS Core: An Integration of the Core IS Courses

    ERIC Educational Resources Information Center

    Albrecht, Conan C.; Romney, Marshall; Lowry, Paul Benjamin; Moody, Greg

    2009-01-01

    This paper describes an innovative, integrated implementation of the core Information Systems courses. While the published IS curriculum provides standards on course "content", it gives little direction on the "implementation" of the courses. At Brigham Young University, we have reengineered the traditional topics of analysis, database, design,…

  15. Core Leadership: Teacher Leaders and Common Core Implementation in Tennessee

    ERIC Educational Resources Information Center

    Aspen Institute, 2014

    2014-01-01

    In the summer of 2012, thousands of teachers across the United States attended several days of professional development workshops. The workshops, which focused on the Common Core State Standards, were part of a Tennessee Department of Education initiative in teacher leadership. The department recruited and trained 200 highly-effective teachers to…

  16. Magnetic Probing of Core Geodynamics

    NASA Technical Reports Server (NTRS)

    Voorhies, Coerte V.

    2004-01-01

    To better understand geomagnetic theory and observation, we can use spatial magnetic spectra for the main field and secular variation to test core dynamical hypotheses against seismology. The hypotheses lead to theoretical spectra which are fitted to observational spectra. Each fit yields an estimate of the radius of Earth's core and uncertainty. If this agrees with the seismologic value, then the hypothesis passes the test. A new way to obtain theoretical spectra extends the hydromagnetic scale analysis of Benton to scale-variant field and flow. For narrow scale flow and a dynamically weak field by the top of Earth's core, this yields a generalized Stevenson-McLeod spectrum for the core-source field, and a secular variation spectrum modulated by a cubic polynomial in spherical harmonic degree n. The former passes the tests. The latter passes many tests, but does not describe rapid dipole decline and quadrupole rebound; some tests suggest it is a bit hard, or rich in narrow scale range. In a core geodynamo, motion of the fluid conductor does work against the Lorentz force. This converts kinetic into magnetic energy which, in turn, is lost to heat via Ohmic dissipation. In the analysis at length-scale 1/k, if one presumes kinetic energy is converted in either eddy-overturning or magnetic free-decay time-scales, then Kolmogorov or other spectra in conflict with observational spectra can result. Instead, the rate work is done roughly balances the dissipation rate, which is consistent with small-scale flow. The conversion time-scale depends on dynamical constraints. These are summarized by the magnetogeostrophic vertical vorticity balance by the top of the core, which includes anisotropic effects of rotation, the magnetic field, and the core-mantle boundary. The resulting theoretical spectra for the core-source field and its SV are far more compatible with observation. The conversion time-scale of order 120 years is pseudo-scale-invariant. Magnetic spectra of other

  17. Magnetic Probing of Core Geodynamics

    NASA Technical Reports Server (NTRS)

    Voorhies, Coerte V.

    2004-01-01

    To better understand geomagnetic theory and observation, we can use spatial magnetic spectra for the main field and secular variation to test core dynmcal hypotheses against seismology. The hypotheses lead to theoretical spectra which are fitted to observational spectra. Each fit yields an estimate of the radius of Earth's core and uncertainty. If this agrees with the seismologic value, then the hypothes pass the test. A new way to obtain theoretical spectra extends the hydromagnetic scale analysis of Benton to scale-variant field and flow. For narrow scale flow and a dynamically weak field by the top of Earth's core, this yields a generalized Stevenson-McLeod spectrum for the core-source field, and a secular variation spectrum modulated by a cubic polynomial in spherical harmonic degree n. The former passes the tests. The latter passes many tests, but does not describe rapid dipole decline and quadrupole rebound; some tests suggest it is a bit hard, or rich in narrow scale change. In a core geodynamo, motion of the fluid conductor does work against the Lorentz force. This converts kinetic into magnetic energy which, in turn, is lost to heat via Ohmic dissipation. In the analysis at lentgh-scale l/k, if one presumes kinetic energy is converted in either eddy- overturning or magnetic free-decay time-scales, then Kolmogorov or other spectra in conflict with observational spectra can result. Instead, the rate work is done roughly balances the dissipation rate, which is consistent with small scale flow. The conversion time-scale depends on dynamical constraints. These are summarized by the magneto-geostrophic vertical vorticity balance by the top of the core, which includes anisotropic effects of rotation, the magnetic field, and the core- mantle boundary. The resulting theoretical spectra for the core-source field and its SV are far more compatible with observation. The conversion time-scale of order l20 years is pseudo-scale-invarient. Magnetic spectra of other

  18. Magnetic Probing of Core Geodynamics

    NASA Astrophysics Data System (ADS)

    Voorhies, C. V.

    2004-05-01

    To better understand geomagnetic theory and observation, we can use spatial magnetic spectra for the main field and secular variation to test core dynamical hypotheses against seismology. The hypotheses lead to theoretical spectra which are fitted to observational spectra. Each fit yields an estimate of the radius of Earth's core and uncertainty. If this agrees with the seismologic value, then the hypotheses pass the test. A new way to obtain theoretical spectra extends the hydromagnetic scale analysis of Benton [1992; GAFD] to scale-variant field and flow [Voorhies, 2004; JGR-SE, in press]. For narrow scale flow and a dynamically weak field by the top of Earth's core, this yields a generalized Stevenson-McLeod spectrum for the core-source field [Voorhies, Sabaka and Purucker, 2002; JGR-P], and a secular variation spectrum modulated by a cubic polynomial in spherical harmonic degree n. The former passes the tests. The latter passes many tests, but does not describe rapid dipole decline and quadrupole rebound; some tests suggest it is a bit hard, or rich in narrow scale change. In a core geodynamo, motion of the fluid conductor does work against the Lorentz force. This converts kinetic into magnetic energy which, in turn, is lost to heat via Ohmic dissipation. In the analysis at length-scale 1/k, if one presumes kinetic energy is converted in either eddy-overturning or magnetic free-decay time-scales, then Kolmogorov or other spectra in conflict with observational spectra can result. Instead, the rate work is done roughly balances the dissipation rate, which is consistent with small scale flow. The conversion time-scale depends on dynamical constraints. These are summarized by the magneto-geostrophic vertical vorticity balance by the top of the core, which includes anisotropic effects of rotation, the magnetic field, and the core-mantle boundary. The resulting theoretical spectra for the core-source field and its SV are far more compatible with observation. The

  19. Critical review of the impact of core stability on upper extremity athletic injury and performance

    PubMed Central

    Silfies, Sheri P.; Ebaugh, David; Pontillo, Marisa; Butowicz, Courtney M.

    2015-01-01

    BACKGROUND: Programs designed to prevent or rehabilitate athletic injuries or improve athletic performance frequently focus on core stability. This approach is based upon the theory that poor core stability increases the risk of poor performance and/or injury. Despite the widespread use of core stability training amongst athletes, the question of whether or not sufficient evidence exists to support this practice remains to be answered. OBJECTIVES: 1) Open a dialogue on the definition and components of core stability. 2) Provide an overview of current science linking core stability to musculoskeletal injuries of the upper extremity. 3) Provide an overview of evidence for the association between core stability and athletic performance. DISCUSSION: Core stability is the ability to control the position and movement of the trunk for optimal production, transfer, and control of forces to and from the upper and lower extremities during functional activities. Muscle capacity and neuromuscular control are critical components of core stability. A limited body of evidence provides some support for a link between core stability and upper extremity injuries amongst athletes who participate in baseball, football, or swimming. Likewise, few studies exist to support a relationship between core stability and athletic performance. CONCLUSIONS: A limited body of evidence exists to support the use of core stability training in injury prevention or performance enhancement programs for athletes. Clearly more research is needed to inform decision making when it comes to inclusion or emphasis of core training when designing injury prevention and rehabilitation programs for athletes. PMID:26537806

  20. Fuel Breeding and Core Behavior Analyses on In Core Fuel Management of Water Cooled Thorium Reactors

    NASA Astrophysics Data System (ADS)

    Permana, Sidik; Sekimoto, Hiroshi; Waris, Abdul; Subhki, Muhamad Nurul; Ismail

    2010-12-01

    Thorium fuel cycle with recycled U-233 has been widely recognized having some contributions to improve the water-cooled breeder reactor program which has been shown by a feasible area of breeding and negative void reactivity which confirms that fissile of 233U contributes to better fuel breeding and effective for obtaining negative void reactivity coefficient as the main fissile material. The present study has the objective to estimate the effect of whole core configuration as well as burnup effects to the reactor core profile by adopting two dimensional model of fuel core management. About more than 40 months of cycle period has been employed for one cycle fuel irradiation of three batches fuel system for large water cooled thorium reactors. All position of fuel arrangement contributes to the total core conversion ratio which gives conversion ratio less than unity of at the BOC and it contributes to higher than unity (1.01) at the EOC after some irradiation process. Inner part and central part give the important part of breeding contribution with increasing burnup process, while criticality is reduced with increasing the irradiation time. Feasibility of breeding capability of water-cooled thorium reactors for whole core fuel arrangement has confirmed from the obtained conversion ratio which shows higher than unity. Whole core analysis on evaluating reactivity change which is caused by the change of voided condition has been employed for conservative assumption that 100% coolant and moderator are voided. It obtained always a negative void reactivity coefficient during reactor operation which shows relatively more negative void coefficient at BOC (fresh fuel composition), and it becomes less negative void coefficient with increasing the operation time. Negative value of void reactivity coefficient shows the reactor has good safety properties in relation to the reactivity profile which is the main parameter in term of criticality safety analysis. Therefore, this

  1. Fuel Breeding and Core Behavior Analyses on In Core Fuel Management of Water Cooled Thorium Reactors

    SciTech Connect

    Permana, Sidik; Sekimoto, Hiroshi; Waris, Abdul; Subhki, Muhamad Nurul; Ismail,

    2010-12-23

    Thorium fuel cycle with recycled U-233 has been widely recognized having some contributions to improve the water-cooled breeder reactor program which has been shown by a feasible area of breeding and negative void reactivity which confirms that fissile of 233U contributes to better fuel breeding and effective for obtaining negative void reactivity coefficient as the main fissile material. The present study has the objective to estimate the effect of whole core configuration as well as burnup effects to the reactor core profile by adopting two dimensional model of fuel core management. About more than 40 months of cycle period has been employed for one cycle fuel irradiation of three batches fuel system for large water cooled thorium reactors. All position of fuel arrangement contributes to the total core conversion ratio which gives conversion ratio less than unity of at the BOC and it contributes to higher than unity (1.01) at the EOC after some irradiation process. Inner part and central part give the important part of breeding contribution with increasing burnup process, while criticality is reduced with increasing the irradiation time. Feasibility of breeding capability of water-cooled thorium reactors for whole core fuel arrangement has confirmed from the obtained conversion ratio which shows higher than unity. Whole core analysis on evaluating reactivity change which is caused by the change of voided condition has been employed for conservative assumption that 100% coolant and moderator are voided. It obtained always a negative void reactivity coefficient during reactor operation which shows relatively more negative void coefficient at BOC (fresh fuel composition), and it becomes less negative void coefficient with increasing the operation time. Negative value of void reactivity coefficient shows the reactor has good safety properties in relation to the reactivity profile which is the main parameter in term of criticality safety analysis. Therefore, this

  2. 38 CFR 0.601 - Core Values.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Core Values. 0.601... ETHICAL CONDUCT, AND RELATED RESPONSIBILITIES Core Values and Characteristics of the Department § 0.601 Core Values. VA's Core Values define VA employees. They describe the organization's culture...

  3. 38 CFR 0.601 - Core Values.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Core Values. 0.601... ETHICAL CONDUCT, AND RELATED RESPONSIBILITIES Core Values and Characteristics of the Department § 0.601 Core Values. VA's Core Values define VA employees. They describe the organization's culture...

  4. Core Today! Rationale and Implications. Revised Edition.

    ERIC Educational Resources Information Center

    Vars, Gordon, Ed.; Larson, Craig, Ed.

    This pamphlet is designed to help educators apply the core concept to current problems and situations in educational settings. The preface establishes the position of the National Association for Core Curriculum. A definition of the core curriculum concept is stated in the introduction. Ten assumptions and beliefs on which the core concept is…

  5. Improved Optical Fiber Chemical Sensors

    NASA Technical Reports Server (NTRS)

    Egalon, Claudio O.; Rogowski, Robert S.

    1994-01-01

    Calculations, based on exact theory of optical fiber, have shown how to increase optical efficiency sensitivity of active-core, step-index-profile optical-fiber fluorosensor. Calculations result of efforts to improve efficiency of optical-fiber chemical sensor of previous concept described in "Making Optical-Fiber Chemical Sensors More Sensitive" (LAR-14525). Optical fiber chemical detector of enhanced sensitivity made in several configurations. Portion of fluorescence or chemiluminescence generated in core, and launched directly into bound electromagnetic modes that propagate along core to photodetector.

  6. Evaluation of a Core Curriculum for Optometric Residents.

    ERIC Educational Resources Information Center

    Heiberger, Michael H.; Suchoff, Irvin B.

    1989-01-01

    A survey of residents and residency supervisors at three Veterans' Administration hospitals affiliated with one school of optometry investigated attitudes toward core optometry curriculum activities. Activities were generally rated well for content and effectiveness of presentation, and the study also provided information for program improvement.…

  7. Team Teaching with Academic Core Curricula Teachers: Using Aviation Concepts

    ERIC Educational Resources Information Center

    Berentsen, Lowell W.

    2006-01-01

    Technology education teachers today have at their disposal the skills, opportunity, experience, ingenuity, expertise, equipment, and environment to greatly improve students' ability to learn and apply the knowledge they have gained in their academic programs. When a technology education teacher joins forces with an academic core teacher, the…

  8. How Will the Common Core Initiative Impact the Testing Industry?

    ERIC Educational Resources Information Center

    Toch, Thomas; Tyre, Peg

    2010-01-01

    The National Governors Association and the Council of Chief State School Officers have sponsored the development of common K-12 education standards in math and English/language arts--a project known as the Common Core State Standards Initiative (CCSSI)--in an effort to improve college readiness for the nation's students and replace the patchwork…

  9. Beyond the Core: Assessing Authentic 21st Century Skills

    ERIC Educational Resources Information Center

    Greenstein, Laura

    2012-01-01

    Principals' wheelbarrows are full of initiatives: closing learning gaps, preparing for the Common Core State Standards, differentiating instruction, and improving college and career readiness, to name a few. Meanwhile, principals have too few assets in their toolboxes to meet all the hefty demands. Taking the long view, it becomes clear that true…

  10. Visual Feedback for Rover-based Coring

    NASA Technical Reports Server (NTRS)

    Backes, Paul; Helmick, Daniel; Bajracharya, Max

    2008-01-01

    Technology for coring from a low-mass rover has been developed to enable core sample acquisition where a planetary rover experiences moderate slip during the coring operation. A new stereo vision technique, Absolute Motion Visual Odometry, is used to measure rover slip during coring and the slip is accommodated through corresponding arm pose updating. Coring rate is controlled by feedback of themeasured force of the coring tool against the environment. Test results in the JPL Marsyard show for the first time that coring from a low-mass rover with slip is feasible.

  11. Core-melt source reduction system

    DOEpatents

    Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

    1995-01-01

    A core-melt source reduction system for ending the progression of a molten core during a core-melt accident and resulting in a stable solid cool matrix. The system includes alternating layers of a core debris absorbing material and a barrier material. The core debris absorbing material serves to react with and absorb the molten core such that containment overpressurization and/or failure does not occur. The barrier material slows the progression of the molten core debris through the system such that the molten core has sufficient time to react with the core absorbing material. The system includes a provision for cooling the glass/molten core mass after the reaction such that a stable solid cool matrix results.

  12. Core-melt source reduction system

    DOEpatents

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-04-25

    A core-melt source reduction system for ending the progression of a molten core during a core-melt accident and resulting in a stable solid cool matrix. The system includes alternating layers of a core debris absorbing material and a barrier material. The core debris absorbing material serves to react with and absorb the molten core such that containment overpressurization and/or failure does not occur. The barrier material slows the progression of the molten core debris through the system such that the molten core has sufficient time to react with the core absorbing material. The system includes a provision for cooling the glass/molten core mass after the reaction such that a stable solid cool matrix results. 4 figs.

  13. Creating a Standardized Process to Meet Core Measure Compliance.

    PubMed

    Kwan, Sarah; Daniels, Melodie; Ryan, Lindsey; Fields, Willa

    2015-01-01

    A standardized process to improve compliance with venous thromboembolism prophylaxis and hospital-based inpatient psychiatric services Core Measures was developed, implemented, and evaluated by a clinical nurse specialist team. The use of a 1-page tool with the requirements and supporting evidence, combined with concurrent data and feedback, ensured success of improving compliance. The initial robust process of education and concurrent and retrospective review follow-up allowed for this process to be successful. PMID:26274512

  14. Disaster and Contingency Planning for Scientific Shared Resource Cores.

    PubMed

    Mische, Sheenah; Wilkerson, Amy

    2016-04-01

    Progress in biomedical research is largely driven by improvements, innovations, and breakthroughs in technology, accelerating the research process, and an increasingly complex collaboration of both clinical and basic science. This increasing sophistication has driven the need for centralized shared resource cores ("cores") to serve the scientific community. From a biomedical research enterprise perspective, centralized resource cores are essential to increased scientific, operational, and cost effectiveness; however, the concentration of instrumentation and resources in the cores may render them highly vulnerable to damage from severe weather and other disasters. As such, protection of these assets and the ability to recover from a disaster is increasingly critical to the mission and success of the institution. Therefore, cores should develop and implement both disaster and business continuity plans and be an integral part of the institution's overall plans. Here we provide an overview of key elements required for core disaster and business continuity plans, guidance, and tools for developing these plans, and real-life lessons learned at a large research institution in the aftermath of Superstorm Sandy. PMID:26848285

  15. Large core fiber optic cleaver

    DOEpatents

    Halpin, J.M.

    1996-03-26

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 {micro}m. 30 figs.

  16. Common Core: Solve Math Problems

    ERIC Educational Resources Information Center

    Strom, Erich

    2012-01-01

    The new common core standards for mathematics demand that students (and teachers!) exhibit deeper conceptual understanding. That's music to the ears of education professor John Tapper, who says teachers have overemphasized teaching procedures--and getting right answers. In his new book, "Solving for Why," he makes a powerful case for moving beyond…

  17. Droplet Core Nuclear Rocket (DCNR)

    NASA Technical Reports Server (NTRS)

    Anghaie, Samim

    1991-01-01

    The most basic design feature of the droplet core nuclear reactor is to spray liquid uranium into the core in the form of droplets on the order of five to ten microns in size, to bring the reactor to critical conditions. The liquid uranium fuel ejector is driven by hydrogen, and more hydrogen is injected from the side of the reactor to about one and a half meters from the top. High temperature hydrogen is expanded through a nozzle to produce thrust. The hydrogen pressure in the system can be somewhere between 50 and 500 atmospheres; the higher pressure is more desirable. In the lower core region, hydrogen is tangentially injected to serve two purposes: (1) to provide a swirling flow to protect the wall from impingement of hot uranium droplets: (2) to generate a vortex flow that can be used for fuel separation. The reactor is designed to maximize the energy generation in the upper region of the core. The system can result in and Isp of 2000 per second, and a thrust-to-weight ratio of 1.6 for the shielded reactor. The nuclear engine system can reduce the Mars mission duration to less than 200 days. It can reduce the hydrogen consumption by a factor of 2 to 3, which reduces the hydrogen load by about 130 to 150 metric tons.

  18. CopperCore Service Integration

    ERIC Educational Resources Information Center

    Vogten, Hubert; Martens, Harrie; Nadolski, Rob; Tattersall, Colin; van Rosmalen, Peter; Koper, Rob

    2007-01-01

    In an e-learning environment there is a need to integrate various e-learning services like assessment services, collaboration services, learning design services and communication services. In this article we present the design and implementation of a generic integrative service framework, called CopperCore Service Integration (CCSI). We will…

  19. Earth rotation and core topography

    NASA Technical Reports Server (NTRS)

    Hager, Bradford H.; Clayton, Robert W.; Spieth, Mary Ann

    1988-01-01

    The NASA Geodynamics program has as one of its missions highly accurate monitoring of polar motion, including changes in length of day (LOD). These observations place fundamental constraints on processes occurring in the atmosphere, in the mantle, and in the core of the planet. Short-timescale (t less than or approx 1 yr) variations in LOD are mainly the result of interaction between the atmosphere and the solid earth, while variations in LOD on decade timescales result from the exchange of angular momentum between the mantle and the fluid core. One mechanism for this exchange of angular momentum is through topographic coupling between pressure variations associated with flow in the core interacting with topography at the core-mantel boundary (CMB). Work done under another NASA grant addressing the origin of long-wavelength geoid anomalies as well as evidence from seismology, resulted in several models of CMB topography. The purpose of work supported by NAG5-819 was to study further the problem of CMB topography, using geodesy, fluid mechanics, geomagnetics, and seismology. This is a final report.

  20. One Health Core Competency Domains.

    PubMed

    Frankson, Rebekah; Hueston, William; Christian, Kira; Olson, Debra; Lee, Mary; Valeri, Linda; Hyatt, Raymond; Annelli, Joseph; Rubin, Carol

    2016-01-01

    The emergence of complex global challenges at the convergence of human, animal, and environmental health has catalyzed a movement supporting "One Health" approaches. Despite recognition of the importance of One Health approaches to address these complex challenges, little effort has been directed at identifying the seminal knowledge, skills, and attitudes necessary for individuals to successfully contribute to One Health efforts. Between 2008 and 2011, three groups independently embarked on separate initiatives to identify core competencies for professionals involved with One Health approaches. Core competencies were considered critically important for guiding curriculum development and continuing professional education, as they describe the knowledge, skills, and attitudes required to be effective. A workshop was convened in 2012 to synthesize the various strands of work on One Health competencies. Despite having different mandates, participants, and approaches, all of these initiatives identified similar core competency domains: management; communication and informatics; values and ethics; leadership; teams and collaboration; roles and responsibilities; and systems thinking. These core competency domains have been used to develop new continuing professional education programs for One Health professionals and help university curricula prepare new graduates to be able to contribute more effectively to One Health approaches. PMID:27679794

  1. Building on the Common Core

    ERIC Educational Resources Information Center

    Conley, David T.

    2011-01-01

    The Common Core State Standards, released in June 2010, offer an opportunity to shift education away from shallow, test-prep instruction and toward a focus on key cognitive skills, writes Conley. Two consortia of states are now developing common assessments to measure these standards--assessments that will be designed to capture deeper, more…

  2. The fluffy core of Enceladus

    NASA Astrophysics Data System (ADS)

    Roberts, James H.

    2015-09-01

    Enceladus is well known for its young south polar terrain, observed by Cassini to emit several GW of heat as well as plumes of vapor and ice. The source of this energy is believed to be tidal dissipation. However, the observed south polar heat flux cannot be sustained over the age of the Solar System. Furthermore, thermal evolution models suggest that any global subsurface ocean should freeze on a timescale of tens to hundreds of My, sharply reducing future tidal heating, unless large amounts of antifreeze are present in the ocean. Here I propose an alternative internal structure for Enceladus, in which the silicate core is fragmented, and that the tidal deformation of the core may be partially controlled by interstitial ice. I find that fragmentation of the core increases tidal dissipation by a factor of 20, consistent with the long-term dynamically sustainable level, even when the interior is completely frozen, but only if the interior starts out warm and tidal heating is strong from the beginning. If this is not the case, radioactive heating will be insufficient to prevent the interior from cooling. Although an ocean need not be present in order for the interior to experience significant tidal heating, all models that dissipate enough heat to prevent runaway cooling are also warm enough to have an ocean. Tidal dissipation in the weak core provides an additional source of heat that may prevent a global subsurface ocean from freezing.

  3. An Overview of Project CORES.

    ERIC Educational Resources Information Center

    Reynolds, Bill J.

    This paper describes the activities of Project Covert and Overt Responses to Education Simulation (CORES) designed to provide an identity for students and faculty desiring to engage in simulation-related research and development activities. Activities for investigating the use of simulation are in the directions of administrative decision making,…

  4. "Common Core Implementation Best Practices"

    ERIC Educational Resources Information Center

    Martin, Carmel

    2014-01-01

    This document presents the testimony of Carmel Martin, Executive Vice President for Policy at the Center for American Progress, delivered at the New York State Office of the Governor Common Core Implementation Panel on Wednesday, February 19, 2014. In this statement, Martin began by saying that The Center for American Progress believes that this…

  5. TEACHING INTERNSHIPS-CORE PROGRAM.

    ERIC Educational Resources Information Center

    Southern Illinois Univ., Carbondale.

    TO DEVELOP TEACHERS FOR STUDENTS IN SEMIPROFESSIONAL OR CAREER PROGRAMS, THE JUNIOR COLLEGE DISTRICT OF ST. LOUIS AND ST. LOUIS COUNTY AND THE SOUTHERN ILLINOIS UNIVERSITY UNDERTOOK A MIDWEST TECHNICAL EDUCATION CENTER PROJECT, FUNDED BY THE FORD FOUNDATION AND CALLED THE TEACHING INTERNSHIP-CORE PROGRAM. GRADUATE CREDIT, AS WELL AS FINANCIAL…

  6. Large core fiber optic cleaver

    DOEpatents

    Halpin, John M.

    1996-01-01

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 .mu.m.

  7. Common Core: Rx for Change

    ERIC Educational Resources Information Center

    Jaeger, Paige

    2012-01-01

    When David Coleman, one of the authors of the Common Core State Standards (CCSS), spoke to New York educators, he stated that over the last forty years 8th grade reading scores have been flat. Despite doubling expenditures on classroom instruction, there has been little growth. Most educators are aware that what worked for the students of the…

  8. The Common Core Math Standards

    ERIC Educational Resources Information Center

    Wurman, Ze'ev; Wilson, W. Stephen

    2012-01-01

    More than 40 states have now signed onto the Common Core standards in English language arts and math, which have been both celebrated as a tremendous advance and criticized as misguided and for bearing the heavy thumbprint of the federal government. This article presents an interview with Ze'ev Wurman and W. Stephen Wilson. Wurman, who was a U.S.…

  9. Common Core State Standards 101

    ERIC Educational Resources Information Center

    Rothman, Robert

    2013-01-01

    The Common Core State Standards (CCSS) represent the first time that nearly every state has set common expectations for what students should know and be able to do. In the past, each state set its own standards, and the results varied widely. And while states collectively developed these common standards, decisions about the curriculum and…

  10. Stability of Molten Core Materials

    SciTech Connect

    Layne Pincock; Wendell Hintze

    2013-01-01

    The purpose of this report is to document a literature and data search for data and information pertaining to the stability of nuclear reactor molten core materials. This includes data and analysis from TMI-2 fuel and INL’s LOFT (Loss of Fluid Test) reactor project and other sources.

  11. One Health Core Competency Domains

    PubMed Central

    Frankson, Rebekah; Hueston, William; Christian, Kira; Olson, Debra; Lee, Mary; Valeri, Linda; Hyatt, Raymond; Annelli, Joseph; Rubin, Carol

    2016-01-01

    The emergence of complex global challenges at the convergence of human, animal, and environmental health has catalyzed a movement supporting “One Health” approaches. Despite recognition of the importance of One Health approaches to address these complex challenges, little effort has been directed at identifying the seminal knowledge, skills, and attitudes necessary for individuals to successfully contribute to One Health efforts. Between 2008 and 2011, three groups independently embarked on separate initiatives to identify core competencies for professionals involved with One Health approaches. Core competencies were considered critically important for guiding curriculum development and continuing professional education, as they describe the knowledge, skills, and attitudes required to be effective. A workshop was convened in 2012 to synthesize the various strands of work on One Health competencies. Despite having different mandates, participants, and approaches, all of these initiatives identified similar core competency domains: management; communication and informatics; values and ethics; leadership; teams and collaboration; roles and responsibilities; and systems thinking. These core competency domains have been used to develop new continuing professional education programs for One Health professionals and help university curricula prepare new graduates to be able to contribute more effectively to One Health approaches. PMID:27679794

  12. Common Core: Fact vs. Fiction

    ERIC Educational Resources Information Center

    Greene, Kim

    2012-01-01

    Despite students' interest in informational text, it has played second fiddle in literacy instruction for years. Now, though, nonfiction is getting its turn in the spotlight. The Common Core State Standards require that students become thoughtful consumers of complex, informative texts--taking them beyond the realm of dry textbooks and…

  13. One Health Core Competency Domains

    PubMed Central

    Frankson, Rebekah; Hueston, William; Christian, Kira; Olson, Debra; Lee, Mary; Valeri, Linda; Hyatt, Raymond; Annelli, Joseph; Rubin, Carol

    2016-01-01

    The emergence of complex global challenges at the convergence of human, animal, and environmental health has catalyzed a movement supporting “One Health” approaches. Despite recognition of the importance of One Health approaches to address these complex challenges, little effort has been directed at identifying the seminal knowledge, skills, and attitudes necessary for individuals to successfully contribute to One Health efforts. Between 2008 and 2011, three groups independently embarked on separate initiatives to identify core competencies for professionals involved with One Health approaches. Core competencies were considered critically important for guiding curriculum development and continuing professional education, as they describe the knowledge, skills, and attitudes required to be effective. A workshop was convened in 2012 to synthesize the various strands of work on One Health competencies. Despite having different mandates, participants, and approaches, all of these initiatives identified similar core competency domains: management; communication and informatics; values and ethics; leadership; teams and collaboration; roles and responsibilities; and systems thinking. These core competency domains have been used to develop new continuing professional education programs for One Health professionals and help university curricula prepare new graduates to be able to contribute more effectively to One Health approaches.

  14. [Core competencies in internal medicine].

    PubMed

    Porcel, J M; Casademont, J; Conthe, P; Pinilla, B; Pujol, R; García-Alegría, J

    2011-06-01

    The working group of the Spanish Society of Internal Medicine (SEMI) on "Competencies of the Internist" has defined the basic medical knowledge, skills and attitudes that all internists in Spain should have. This list of competencies represents the Internal Medicine core curriculum within the context of the future educational framework of medical specialties in Health Sciences.

  15. One Health Core Competency Domains.

    PubMed

    Frankson, Rebekah; Hueston, William; Christian, Kira; Olson, Debra; Lee, Mary; Valeri, Linda; Hyatt, Raymond; Annelli, Joseph; Rubin, Carol

    2016-01-01

    The emergence of complex global challenges at the convergence of human, animal, and environmental health has catalyzed a movement supporting "One Health" approaches. Despite recognition of the importance of One Health approaches to address these complex challenges, little effort has been directed at identifying the seminal knowledge, skills, and attitudes necessary for individuals to successfully contribute to One Health efforts. Between 2008 and 2011, three groups independently embarked on separate initiatives to identify core competencies for professionals involved with One Health approaches. Core competencies were considered critically important for guiding curriculum development and continuing professional education, as they describe the knowledge, skills, and attitudes required to be effective. A workshop was convened in 2012 to synthesize the various strands of work on One Health competencies. Despite having different mandates, participants, and approaches, all of these initiatives identified similar core competency domains: management; communication and informatics; values and ethics; leadership; teams and collaboration; roles and responsibilities; and systems thinking. These core competency domains have been used to develop new continuing professional education programs for One Health professionals and help university curricula prepare new graduates to be able to contribute more effectively to One Health approaches.

  16. Laminated grid and web magnetic cores

    DOEpatents

    Sefko, John; Pavlik, Norman M.

    1984-01-01

    A laminated magnetic core characterized by an electromagnetic core having core legs which comprise elongated apertures and edge notches disposed transversely to the longitudinal axis of the legs, such as high reluctance cores with linear magnetization characteristics for high voltage shunt reactors. In one embodiment the apertures include compact bodies of microlaminations for more flexibility and control in adjusting permeability and/or core reluctance.

  17. Experience with the BEACON core monitoring system

    SciTech Connect

    Beard, C.L. ); Icide, C.A. )

    1992-01-01

    The BEACON operational core support system was developed for use in pressurized water reactors to provide an integrated system to perform reactor core monitoring, core measurement reduction, core analysis and follow, and core predictions. It is based on the very fast and accurate three-dimensional SPNOVA nodal program. The experience to date has shown the importance of an accurate integrated system. The benefits accrued are greater for the total system than the benefits that are possible separately.

  18. Magnectic Probing of Core Geodynamics

    NASA Technical Reports Server (NTRS)

    Voorhies, Coerte

    2004-01-01

    To better understand geomagnetic theory and observation, we can use spatial magnetic spectra for the main field and secular variation to test core dynamical hypotheses against seismology. The hypotheses lead to theoretical spectra which are fitted to observational spectra. Each fit yields an estimate of the radius of Earth s core and uncertainty. If this agrees with the seismologic value, then the hypotheses pass the test. A new way to obtain theoretical spectra extends the hydromagnetic scale analysis of Benton to scale-variant field and flow. For narrow scale flow and a dynamically weak field by the top of Earth s core, this yields a JGR-PI, and a secular variation spectrum modulated by a cubic polynomial in spherical harmonic degree n. The former passes the tests. The latter passes many tests, but does not describe rapid dipole decline and quadrupole rebound; some tests suggest it is a bit hard, or rich in narrow scale change.In a core geodynamo, motion of the fluid conductor does work against the Lorentz force. This converts kinetic into magnetic energy which, in turn, is lost to heat via Ohmic dissipation. In the analysis at length- scale l/k, if one presumes kinetic energy is converted in either eddy- overturning or magnetic free-decay time-scales, then Kolmogorov or other spectra in conflict with observational spectra can result. Instead, the rate work is done roughly balances the dissipation rate, which is consistent with small scale flow. The conversion time-scale depends on dynamical constraints. These are summarized by the magneto- geostrophic vertical vorticity balance by the top of the core, which includes anisotropic effects of rotation, the magnetic field, and the core-mantle boundary. The resulting theoretical spectra for the core- source field and its SV are far more compatible with observation. The conversion time-scale of order 120 years is pseudo-scale-invariant. Magnetic spectra of other planets may differ; however, if a transition to non

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

    NASA Astrophysics Data System (ADS)

    Umar, Efrizon; Fiantini, Rosalina

    2010-06-01

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

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

    SciTech Connect

    Umar, Efrizon; Fiantini, Rosalina

    2010-06-22

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