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Sample records for astrid haljas romi

  1. ASTRID rocket flight test

    SciTech Connect

    Whitehead, J.C.; Pittenger, L.C.; Colella, N.J.

    1994-07-01

    On February 4, 1994, we successfully flight tested the ASTRID rocket from Vandenberg Air Force Base. The technology for this rocket originated in the Brilliant Pebbles program and represents a five-year development effort. This rocket demonstrated how our new pumped-propulsion technology-which reduced the total effective engine mass by more than one half and cut the tank mass to one fifth previous requirements-would perform in atmospheric flight. This demonstration paves the way for potential cost-effective uses of the new propulsion system in commercial aerospace vehicles, exploration of the planets, and defense applications.

  2. Princess Astrid Coast, Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The continent of Antarctica is almost completely covered by a thick blanket of ice, punctuated only by steep mountain peaks and a handful of dry valleys. Antarctica is also ringed by a permanent ice shelf, and that is surrounded by seasonal sea ice. The image above, acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) on September 26, 2001, shows many of the types of ice found in Antarctica. At the bottom of the image is the ice of the continental glacier, which is up to 4,000 meters thick in the interior. These thick glaciers are held in place by coastal mountain ranges. Some ice does flow through the mountains, spilling onto the relatively flat land of the Princess Astrid Coast. Cold air also spills over the mountains, creating very strong and persistent 'katabatic' winds. These scour the snow off the tops of the glaciers, leaving pale blue patches of bare ice. Above the coastline is the ice shelf, which is much smoother. There, glacial ice actually floats on the sea surface. Beyond that is the chaotic surface of the sea ice, which has been solidifying all winter long. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  3. On the Astrid asteroid family

    NASA Astrophysics Data System (ADS)

    Carruba, V.

    2016-09-01

    Among asteroid families, the Astrid family is peculiar because of its unusual inclination distribution. Objects at a ≃ 2.764 au are quite dispersed in this orbital element, giving the family a `crab-like' appearance. Recent works showed that this feature is caused by the interaction of the family with the s - sC nodal secular resonance with Ceres, that spreads the inclination of asteroids near its separatrix. As a consequence, the currently observed distribution of the vW component of terminal ejection velocities obtained from inverting Gauss equation is quite leptokurtic, since this parameter mostly depends on the asteroids inclination. The peculiar orbital configuration of the Astrid family can be used to set constraints on key parameters describing the strength of the Yarkovsky force, such as the bulk and surface density and the thermal conductivity of surface material. By simulating various fictitious families with different values of these parameters, and by demanding that the current value of the kurtosis of the distribution in vW be reached over the estimated lifetime of the family, we obtained that the thermal conductivity of Astrid family members should be ≃0.001 W m-1 K-1, and that the surface and bulk density should be higher than 1000 kg m-3. Monte Carlo methods simulating Yarkovsky and stochastic Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) evolution of the Astrid family show its age to be T = 140 ± 30 Myr old, in good agreement with estimates from other groups. Its terminal ejection velocity parameter is in the range V_{EJ}= 5^{+17}_{-5} m s-1. Values of VEJ larger than 25 m s-1 are excluded from constraints from the current inclination distribution.

  4. ROMY - The First Large 3D Ring Laser Structure for Seismology and Geodesy

    NASA Astrophysics Data System (ADS)

    Schreiber, Karl Ulrich; Igel, Heiner; Wassermann, Joachim; Lin, Chin-Jen; Gebauer, André; Wells, Jon-Paul

    2016-04-01

    Large ring laser gyroscopes have matured to the point that they can routinely observe rotational motions from geophysical processes that can be used in geodesy and seismology. The ring lasers used for this purpose enclose areas between 16 and 800 square meters and have in common that they can only measure rotations around the vertical axis because the structures are horizontally placed on the floor. With the ROMY project we have embarked on the construction of a full 3-dimensional rotation sensor. The actual apparatus consists of four individual triangular ring lasers arranged in the shape of a tetrahedron with 12 m of length on each side. At each corner of the tetrahedron three of the ring lasers are rigidly tied together to the same mechanical reference. The overall size of the installation provides a promising compromise between sensor stability on one side and sensor resolution on the other side. This talk introduces the technical concept of the ROMY ring laser installation and will also briefly outline the requirements for applications in space geodesy.

  5. ASTRiDE: Automated Streak Detection for Astronomical Images

    NASA Astrophysics Data System (ADS)

    Kim, Dae-Won

    2016-05-01

    ASTRiDE detects streaks in astronomical images using a "border" of each object (i.e. "boundary-tracing" or "contour-tracing") and their morphological parameters. Fast moving objects such as meteors, satellites, near-Earth objects (NEOs), or even cosmic rays can leave streak-like traces in the images; ASTRiDE can detect not only long streaks but also relatively short or curved streaks.

  6. Aerodynamic, structural, and trajectory analysis of ASTRID-1 vehicle

    SciTech Connect

    Glover, L.S.; Iwaskiw, A.P.; Oursler, M.A.; Perini, L.L.; Schaefer, E.D.

    1994-02-10

    The Johns Hopkins University/Applied Physics Laboratory, JHU/API, in support of Lawrence Livermore National Laboratory, LLNL, is conducting aerodynamic, trajectory, and structural analysis of the Advanced Single Stage Technology Rapid Insertion Demonstration (ASTRID) vehicle, being launched out of Vandenberg Air Force Base (VAFB) in February 1994. The launch is designated ASTRID-1 and is the first in a series of three that will be launched out of VAFB. Launch dates for the next two flights have not been identified, but they are scheduled for the 1994-1995 time frame. The primary goal of the ASTRID-1 flight is to test the LLNL light weight thrust on demand bi-propellant pumped divert propulsion system. The system is employed as the main thrusters for the ASTRID-1 vehicle and uses hydrazine as the mono-propellant. The major conclusions are: (1) The vehicle is very stable throughout flight (stability margin = 17 to 24 inches); (2) The aerodynamic frequency and the roll rate are such that pitch-roll interactions will be small; (3) The high stability margin combined with the high launcher elevation angle makes the vehicle flight path highly sensitive to perturbations during the initial phase of flight, i.e., during the first second of flight after leaving the rail; (4) The major impact dispersions for the test flight are due to winds. The wind impact dispersions are 90% dictated by the low altitude, 0 to 1000 ft., wind conditions; and (5) In order to minimize wind dispersions, head wind conditions are favored for the launch as November VAFB mean tail winds result in land impacts. The ballistic wind methodology can be employed to assess the impact points of winds at the launch site.

  7. Generation IV reactors and the ASTRID prototype: Lessons from the Fukushima accident

    NASA Astrophysics Data System (ADS)

    Gauché, François

    2012-05-01

    In France, the ASTRID prototype is a sodium-cooled fast neutron industrial demonstrator, fulfilling the criteria for Generation IV reactors. ASTRID will meet safety requirements as stringent as for 3rd generation reactors, and take into account lessons from the Fukushima accident. The objectives are to reinforce the robustness of the safety demonstration for all safety functions. ASTRID will feature an innovative core with a negative sodium void coefficient, take advantage of the large thermal inertia of SFRs for decay heat removal, and provide for a design either eliminating the sodium-water reaction, or guaranteeing no consequences for safety in case such reaction would take place.

  8. 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)

  9. 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)

  10. Use of simplified PSA studies in support of the ASTRID design process

    SciTech Connect

    Gauthe, P.; Curnier, F.; Bertrand, F.; Vincon, L.; Jouve, S.; Balmain, M.; Rychkov, V.; Banchieri, Y.

    2012-07-01

    In the framework of the French Act of 28 June 2006 about nuclear materials and waste management, a GEN IV and actinides incineration demonstration prototype is to be commissioned in the 2020 decade. In this objective a prototype called ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) is proposed to demonstrate the progress made in SFR technology at an industrial scale by qualifying innovative options, some of which still remain open in the areas requiring improvements, especially safety and operability. More specifically, we aim for a level of safety that is at least equivalent to that of the EPR (third generation), with improvements made in SFR-specific fields. The integration of safety issues in the early phase of the design of ASTRID is necessarily expected. For this purpose, CEA and its partners AREVA and EDF have planned to perform a level-1 PSA to support and orientate the preliminary design of ASTRID reactor. This paper presents the PSA approach and current studies for the assessment of safety systems and the future work to be done for the 2012-2014 period. The preliminary preparation of PSA studies is presented: objectives and scope of the early design phase PSA, definition of core damage states, selection and grouping of initiating events, assessment of safety functions and related systems. Work under progress is also presented: modelling of event trees, construction of fault trees of safety systems, transient calculations of accident sequences with the CATHARE2 code and reliability data assessment. Main objectives of a level-1 PSA performed at conceptual design stage are an early assessment of the safety architecture of the reactor and findings about the most effective areas for improvement, but also the identification of dominant accident sequences and comparison with alternative designs. After the elaboration of a simplified level-1 PSA model for nominal state and main internal initiators, various design alternatives will be

  11. Laser cooling of {sup 24}Mg{sup +} in the ASTRID storage ring

    SciTech Connect

    Nielsen, J.S.; Hangst, J.S.; Poulsen, O.; Shi, P. |; Schiffer, J.P. |; Wanner, B.

    1994-05-01

    Laser cooling of {sup 24}Mg{sup +} has now begun at the ASTRID storage ring. In contrast to {sup 7}Li{sup +}, which has been used up to now, it is now possible for the laser to interact with all of the beam. In this paper some of the results from the first beam time with {sup 24}Mg{sup +} are described. By frequency chirping a single laser, laser cooling has been performed on a coasting beam, and first evidence of sympathetic transverse cooling has been observed.

  12. 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)

  13. Energetic Neutral Atom Imager on the Swedish Microsatellite Astrid. Paper 5

    NASA Technical Reports Server (NTRS)

    Barabash, S.; Norberg, O.; Roelof, E. C.; Lundin, R.; Olsen, S.; Lundin, K.; Brandt, Pontus C:son; Chase, C. J.; Mauk, B. H.; Koskinen, H.; Ryno, J.

    1999-01-01

    The Swedish microsatellite ASTRID was launched by a Russian Cosmos rocket on January 24, 1995 into a 1000 km circular orbit with 83 deg inclination. Besides the main objective of technological demonstration, imaging of energetic neutral atoms (ENAS) was attempted. The imager detected ENA in the energy range 0.1 - 140 keV utilizing two different techniques. Neutrals of the energy 13 - 140 keV were recorded by 14 solid state detectors with the total field of view 5 deg x 322 deg. For half a spin (approx. 1.5 s) of the ASTRID spacecraft, almost all of space was covered with an angular resolution 2.5 deg x 25 deg. Less energetic neutrals of approx. 0.1 - 70 keV were converted on a graphite target into secondary particles which then were detected by a microchannel plate with 32 anodes. A fraction of primary neutrals was directly reflected towards the sensor. This technique provided the total ENA flux with an angular resolution 4.6 deg x 11.5 deg. The instrument weight is 3.13 kg. Successful operation of the instrument during the first 5 weeks of the mission provided the first ENA images of the ring current at low altitudes.

  14. The pre-conceptual design of the nuclear island of ASTRID

    SciTech Connect

    Saez, M.

    2012-07-01

    The CEA is involved in a substantial effort on the ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) pre-conceptual design in cooperation with EDF, as experienced Sodium-cooled Fast Reactor (SFR) operator, AREVA, as experienced SFR Nuclear Island engineering company and components designer, ALSTOM POWER as energy conversion system designer and COMEX NUCLEAIRE as mechanical systems designer. The CEA is looking for other partnerships, in France and abroad. The ASTRID preliminary design is based on a sodium-cooled pool reactor of 1500 MWth generating about 600 MWe, which is required to guarantee the representativeness of the reactor core and the main components with regard to future commercial reactors. ASTRID lifetime target is 60 years. Two Energy Conversion Systems are studied in parallel until the end of 2012: Rankine steam cycle or Brayton gas based energy conversion cycle. ASTRID design is guided by the following major objectives: improved safety, simplification of structures, improved In Service Inspection and Repair (ISIR), improved manufacturing conditions for cost reduction and increased quality, reduction of risks related to sodium fires and water/sodium reaction, and improved robustness against external hazards. The core is supported by a diagrid, which lay on a strong back to transfer the weight to the main vessel. AREVA is involved in a substantial effort in order to improve the core support structure in particular regarding the ISIR and the connection to primary pump. In the preliminary design, the primary system is formed by the main vessel and the upper closure comprising the reactor roof, two rotating plugs - used for fuel handling - and the components plugs located in the roof penetrations. The Above Core Structure deflects the sodium flow in the hot pool and provides support to core instrumentation and guidance of the control rod drive mechanisms. The number of the major components in the main vessel, primary pumps

  15. ASTRID: A 3D Eulerian software for subcooled boiling modelling - comparison with experimental results in tubes and annuli

    SciTech Connect

    Briere, E.; Larrauri, D.; Olive, J.

    1995-09-01

    For about four years, Electricite de France has been developing a 3-D computer code for the Eulerian simulation of two-phase flows. This code, named ASTRID, is based on the six-equation two-fluid model. Boiling water flows, such as those encountered in nuclear reactors, are among the main applications of ASTRID. In order to provide ASTRID with closure laws and boundary conditions suitable for boiling flows, a boiling model has been developed by EDF and the Institut de Mecanique des Fluides de Toulouse. In the fluid, the heat and mass transfer between a bubble and the liquid is being modelled. At the heating wall, the incipient boiling point is determined according to Hsu`s criterion and the boiling heat flux is split into three additive terms: a convective term, a quenching term and a vaporisation term. This model uses several correlations. EDF`s program in boiling two-phase flows also includes experimental studies, some of which are performed in collaboration with other laboratories. Refrigerant subcooled boiling both in tubular (DEBORA experiment, CEN Grenoble) and in annular geometry (Arizona State University Experiment) have been computed with ASTRID. The simulations show the satisfactory results already obtained on void fraction and liquid temperature. Ways of improvement of the model are drawn especially on the dynamical part.

  16. Probabilistic margin evaluation on accidental transients for the ASTRID reactor project

    NASA Astrophysics Data System (ADS)

    Marquès, Michel

    2014-06-01

    ASTRID is a technological demonstrator of Sodium cooled Fast Reactor (SFR) under development. The conceptual design studies are being conducted in accordance with the Generation IV reactor objectives, particularly in terms of improving safety. For the hypothetical events, belonging to the accidental category "severe accident prevention situations" having a very low frequency of occurrence, the safety demonstration is no more based on a deterministic demonstration with conservative assumptions on models and parameters but on a "Best-Estimate Plus Uncertainty" (BEPU) approach. This BEPU approach ispresented in this paper for an Unprotected Loss-of-Flow (ULOF) event. The Best-Estimate (BE) analysis of this ULOFt ransient is performed with the CATHARE2 code, which is the French reference system code for SFR applications. The objective of the BEPU analysis is twofold: first evaluate the safety margin to sodium boiling in taking into account the uncertainties on the input parameters of the CATHARE2 code (twenty-two uncertain input parameters have been identified, which can be classified into five groups: reactor power, accident management, pumps characteristics, reactivity coefficients, thermal parameters and head losses); secondly quantify the contribution of each input uncertainty to the overall uncertainty of the safety margins, in order to refocusing R&D efforts on the most influential factors. This paper focuses on the methodological aspects of the evaluation of the safety margin. At least for the preliminary phase of the project (conceptual design), a probabilistic criterion has been fixed in the context of this BEPU analysis; this criterion is the value of the margin to sodium boiling, which has a probability 95% to be exceeded, obtained with a confidence level of 95% (i.e. the M5,95percentile of the margin distribution). This paper presents two methods used to assess this percentile: the Wilks method and the Bootstrap method ; the effectiveness of the two methods

  17. Energetic Neutral Atom Imaging at Low Altitudes from the Swedish Microsatellite Astrid: Extraction of the Equatorial Ion Distribution. Paper 2

    NASA Technical Reports Server (NTRS)

    Brandt, Pontus C:son; Barabash, Stas; Roelof, Edmond C.; Chase, Christopher J.

    1999-01-01

    Energetic neutral atom (ENA) images obtained by the ENA imager on- board the Astrid satellite in the polar cap at 1000 km during a moderate magnetic storm (Dst greater than or equal to 80 nT) on 8 February 1995 are simulated using a parameterized model of the equatorial ion distribution and a six-component Chamberlain exo-sphere with parameters from the MSISE-90 model. By changing the ion parameters until a matching ENA image is obtained one can extract the equatorial ion distribution. Four consecutive images from different view points several of minutes apart are simulated assuming H(+) and O(+), respectively, as parent ions. The optimal set of parameters is extracted by minimizing the chi(exp 2) difference between simulated and observed ENA image using Powell's minimization algorithm. The optimal equatorial model ion distribution consists of O(+) peaked in around dusk. The lower intensity of fluxes obtained from vantage points closer to the pole is an effect of the loss cone of the parent ion distribution being empty.

  18. Two Types of Transpolar Arc Development, Event Studies with Data Set of ASTRID-2, DMSP, FAST, and SuperDARN

    NASA Technical Reports Server (NTRS)

    Narita, Yasuhito; Maezawa, Kiyoshi; Toshinori, Mukai; Kullen, A.; Ivchenko, N.; Marklund, G.; Frederick, R.; Carlson, C. W.; Spann, J. F.; Parks, G. K.; Six, N. Frank (Technical Monitor)

    2002-01-01

    Aurorae which appear in the polar cap are called transpolar arcs, polar cap arcs, sun-aligned arcs, or occasionally Theta-aurora because of its spatial distribution resembling Greek character 'Theta.' Morphology, IMF (Interplanetary Magnetic Field) relationship, and ionospheric convection patterns were studied in quest of mechanisms of transpolar arcs. Four events were analyzed: 1999/Jan/22/19:00 - 23/01:30 (1 event: a) 1999/Jan/24/06:00 - 10:00 (1 event: b) 1999/Feb/1 1/20:00 - 12/02:00 (2 events: c, d), with data set of ExB drift velocity data obtained by electric field measurements of ASTRID-2 and FAST, DMSP ion driftmeter data, and line-of-sight velocity data of SuperDARN. POLAR-UVI image data were used for spatial and temporal variations of transpolar arcs and ACE data set were used for investigation of IMF relationship. IMF-Bz was strongly positive (Bz from +8nT to +20 nT) during periods of all four transpolar arcs. In events (a),(b),(c), transpolar arcs appeared immediately after the direction of IMF turned northward, though IMF was fluctuating in event (b). A sudden increase of IMF-By, from +3nT to +18nT, was observed in event (d). Two different types of transpolar arc development were observed in POLAR-UVI: one which begins as a split from dawn or dusk sector of auroral oval and shifts poleward in event (a),(c),(d), and another which is initially a patch of auroral oval disturbed by substorm but develops as a transpolar arc, forming a growing finger-like shape from midnight sector (event b). Sunward flow, associated with positive IMF-Bz, were observed within newly-created polar caps in event (a),(c),(d). Not clear ionospheric convection pattern was seen across the polar cap arc in event (b) die to limitation of data set. In event (c), O+ with energy more than 1 keV were observed by FAST within a transpolar arc, suggesting that their origin be from plasma sheet. Transpolar arcs are thought to be projection of plasma sheet bifurcation into lobe regime. There

  19. Two Types of Transpolar Arc Development, Event Studies With Data Set of Astrid-2, Dmsp, Fast, and Superdarn

    NASA Astrophysics Data System (ADS)

    Narita, Y.; Maezawa, K.; Kullen, A.; Ivchenko, N.; Marklund, G.; Carlson, C. W.; Spann, J. F.; Parks, G. K.; Superdarn Team

    Auroras which appear in the polar cap are called transpolar arcs, polar cap arcs, sun- aligned arcs, or occasionally Theta-aurora because of its spatial distribution resem- bling Greek character 'Theta.' Morphology, IMF(Interplanetary Magnetic Field) rela- tionship, and ionospheric convection patterns were studied in quest of mechanisms of transpolar arcs. Four events were analyzed: 1999/Jan/22/19:00 - 23/01:30 (1 event: a) 1999/Jan/24/06:00 - 10:00 (1 event: b) 1999/Feb/11/20:00 - 12/02:00 (2 events: c, d) , with data set of ExB drift velocity data obtained by electric field measurements of ASTRID-2 and FAST, DMSP ion driftmeter data, and line-of- sight velocity data of SuperDARN. POLAR-UVI image data were used for spatial and temporal variations of transpolar arcs and ACE data set were used for investigation of IMF relationship. IMF-Bz was strongly positive (Bz from +8nT to +20 nT) during periods of all four transpolar arcs. In events (a),(b),(c), transpolar arcs appeared immediately after the direction of IMF turned northward, though IMF was fluctuating in event (b). A sudden increase of IMF-By, from +3nT to +18nT, was observed in event (d). Two different types of transpolar arc development were observed by POLAR-UVI: one which begins as a split from dawn or dusk sector of auroral oval and shifts poleward in events (c),(d); another which is initially a patch of auroral oval disturbed by substorm but develops as a transpolar arc, forming a growing finger-like shape from midnight sector in event (b). Sunward flow, associated with positive IMF-Bz, were observed within newly-created polar caps in events (a),(c),(d). Not clear ionospheric convection pattern was seen across the transpolar arc in event (b) due to limitation of data set. Isotropic ions with energy more than 1 keV were observed within transpolar arcs. From these 1 observations it is concluded that the origin of transpolar arcs is from the plasma sheet. This is consistent with the view that transpolar

  20. Energetic Neutral Atom Imaging at Low Altitudes from the Swedish Microsatellite Astrid: Images and Spectral Analysis. Paper 1

    NASA Technical Reports Server (NTRS)

    Brandt, Pontus C:son; Barabash, Stas; Norberg, Olle; Lundin, Rickard; Roelof, Rdmond C.; Chase, Christopher J.

    1999-01-01

    Observations of energetic neutral atoms (ENA) in the energy range 26- 52 keV are reported from four occasions during geomagnetically disturbed periods. The data were acquired by the ENA imager flown on the Swedish microsatellite Astrid in a 1000 km circular orbit with 83 deg inclination. The ENA imager separates charged particles from neutrals through an electrostatic deflection system in the energy range between 0.1 and 114 keV. ENA images obtained from vantage points in the polar cap and in the afternoon magnetic local time (MLT) hours looking into the antisunward hemisphere show intense ENA fluxes (approx. 10(exp 4)/sq cm sr s over 26-37 keV) coming from the dusk region and low altitudes (approx. 300 km). The morphology shows no relation to local magnetic field excluding the possibility of charged particle detection. It is concluded that the source of these ENAs are precipitating/mirroring ions from the ring current/trapped radiation interacting with the exobase on auroral L-shells and in the dusk region. The observed ENA fluxes show a relation with Kp and Dst geomagnetic indices. The observed ENA spectrum from a geomagnetic storm on February 8, 1995, is investigated in more detail and compared to the parent ion spectrum obtained by the Defense Meteorological Satellite Project (DMSP) satellite, Fl2, during the same period on L = 6 +/- 2 around dusk. The observed ENA spectral slope is used to derive the parent ion spectral temperature. The derived ion temperatures range is 3.0 - 6.0 keV for H and 4.5 - 8.5 keV for O. The higher of these ion temperatures comes closest in agreement to the extrapolated DMSP spectrum leading us to favor O over H as the species of the detected ENAS. It is shown that the detected ENAs must have been produced at L greater than or equal to 6 to reach the detector without atmospheric attenuation and that the main energy dependence of the ENA spectrum, apart from the parent ion spectrum, is governed by the energy dependence of the charge

  1. IRE1α Stands astride Many Paths to Insulin Production.

    PubMed

    Sedwick, Caitlin

    2015-10-01

    A new study shows that components of the unfolded protein pathway are needed to help manage the production of vast amounts of insulin by pancreatic β cells in response to glucose stimulation. Read the Research Article. PMID:26469794

  2. From pluripotency to forebrain patterning: an in vitro journey astride embryonic stem cells.

    PubMed

    Lupo, Giuseppe; Bertacchi, Michele; Carucci, Nicoletta; Augusti-Tocco, Gabriella; Biagioni, Stefano; Cremisi, Federico

    2014-08-01

    Embryonic stem cells (ESCs) have been used extensively as in vitro models of neural development and disease, with special efforts towards their conversion into forebrain progenitors and neurons. The forebrain is the most complex brain region, giving rise to several fundamental structures, such as the cerebral cortex, the hypothalamus, and the retina. Due to the multiplicity of signaling pathways playing different roles at distinct times of embryonic development, the specification and patterning of forebrain has been difficult to study in vivo. Research performed on ESCs in vitro has provided a large body of evidence to complement work in model organisms, but these studies have often been focused more on cell type production than on cell fate regulation. In this review, we systematically reassess the current literature in the field of forebrain development in mouse and human ESCs with a focus on the molecular mechanisms of early cell fate decisions, taking into consideration the specific culture conditions, exogenous and endogenous molecular cues as described in the original studies. The resulting model of early forebrain induction and patterning provides a useful framework for further studies aimed at reconstructing forebrain development in vitro for basic research or therapy. PMID:24643740

  3. Astride a Long-Dead Horse: Mainstream Outdoor Education Theory and the Central Curriculum Problem

    ERIC Educational Resources Information Center

    Brookes, Andrew

    2004-01-01

    In 1859 Herbert Spencer recognised that the key curriculum issue was not what to include but what to leave out. What to leave out marked a shift in curriculum discourse from a search for universal approaches and absolute principles towards curriculum questions understood as only resolvable relative to particular social contexts. Yet outdoor…

  4. MAP of F1 and V antigens from Yersinia pestis astride innate and adaptive immune response.

    PubMed

    Rai, Reeta; Das, Baijnath; Choudhary, Nageshwar; Talukdar, Ayantika; Rao, Donthamsetty Nageswara

    2015-10-01

    Yersinia pestis, a causative agent of plague, has a plethora of armors to fight against major components of innate immunity and survive within host cells. Dendritic cells and macrophages are important antigen presenting cells for effective immune response. This report is focused on the changes in DC activation and TLR2 and TLR4 expression on macrophages induced by MAP of F1 and V antigens of Y. pestis. F1 and V MAPs bear potential synthetic T and B cell epitopes from F1 and V protein respectively. We evaluated these parameters in DC's isolated from spleen and lamina propria and macrophages isolated from peritoneal lavage of mice after intranasal immunization. F1 MAP and V MAP significantly increased the expression of CD80 and CD86 on CD11c(+) dendritic cells isolated from spleen and lamina propria as well as intracellular IL-12 levels. Similarly, in macrophages derived from peritoneal cavity, the above formulation enhanced TLR2 and TLR4 expression. Again after in vitro stimulation with F1 and V MAP these macrophages produced significantly high IL12 and TNFα. The study clearly indicates involvement of DC and macrophages for efficient antigen presentation to immune cells. From this study we conclude that F1MAP and VMAP ameliorate innate immune mechanism. These two synthetic constructs exert their effect via TLR2 and TLR4, leading to the production of proinflammatory cytokines by macrophages and are able to increase DC activation, that could be helpful in generation of adaptive immunity as well as is important strong immune response. PMID:26188288

  5. Geothermal potential of Caledonian granites underlying Upper Palaeozoic sedimentary basins astride the Iapetus Suture Zone in Ireland

    NASA Astrophysics Data System (ADS)

    Fritschle, Tobias; Daly, J. Stephen; Whitehouse, Martin J.; McConnell, Brian; Buhre, Stephan

    2014-05-01

    Upper Palaeozoic sedimentary basins in Ireland overlie crystalline rocks within the Caledonian Iapetus Suture Zone. Beneath these basins, Lower Palaeozoic rocks, formed and deformed during the Caledonian orogenic cycle, were intruded by c. 420-390 Ma late-tectonic granites at various tectonic levels. These include the subsurface Kentstown and Glenamaddy granites discovered by mineral exploration drilling. While these granites comprise actual targets for Enhanced Geothermal System (EGS) exploration, several others likely exist based on geophysical considerations. In order to test the regional geothermal potential, the buried granites as well as analogue exposed rocks are being investigated geochemically. The geothermal potential of the intrusives depends on their heat production rate (HPR), which is calculated using rock density and concentrations of the heat producing elements (HPE) uranium, thorium and potassium. In spite of their close spacing and similar ages, the whole-rock geochemistry of the granites varies significantly, but with no obvious geographical control (Fritschle et al., 2013; 2014). The granite HPR values range from 1.4 μW/m3 for the Dhoon Granite (Isle of Man) to 4.9 μW/m3 for the Drogheda Granite (Ireland). This compares with the average HPR for a 'typical' granite of 2.7 μW/m3 (Goldstein et al., 2009). It is demonstrated that an elevated HPR of a granite can be related to enrichment in one of the HPE alone (e.g., uranium-enrichment in the Foxdale Granite (Isle of Man), or thorium-enrichment in the Drogheda Granite). Enrichment in HPE in a granite may occur due to different reasons including hydrothermal (re-) distribution of uranium, or the assimilation of thorium-rich wall-rocks. Hence, the distribution of the HPE in particular minerals, veins and source lithologies, along with the petrophysical characteristics of the sedimentary basins and the granites' petrogenesis, are currently being investigated as possible mechanisms controlling their heat production budget. Fritschle, T., Daly, J.S., Whitehouse, M.J., McConnell, B., Buhre, S., 2013. U-Pb Zircon Ages from Granites in the Iapetus Suture Zone in Ireland and the Isle of Man. Mineralogical Magazine, 77(5): 1115. Fritschle, T., Daly, J.S., Whitehouse, M.J., McConnell, B., Buhre, S., 2014. Zircon geochronology and Hf-O isotope geochemistry from granites in the Iapetus Suture Zone in Ireland and the Isle of Man. This issue. Goldstein, B.A., Hill, A.J., Long, A., Budd, A.R., Ayling, B., Malavazos, M., 2009. Hot rocks down under - evolution of a new energy industry. Geothermal Resources Council Transactions, 33: 185-198.

  6. Seismic hazards astride the boundary between the eastern Snake River Plain and northern Basin and Range Province Idaho

    SciTech Connect

    Wong, I.G.; Hemphill-Haley, M.A.; Sawyer, T.L. ); Coppersmith, K.J.; Youngs, R.R. ); Smith, R.P.; Jackson, S.M.; Hackett, W.R. ); Silva, W.J.; Stark, C.M. ); Knuepfer, P.L.K. . Dept. of Geological Sciences); Bruhn, R.L.; Wu, D. . Dept. of Geology and Geophysics)

    1993-04-01

    The occurrence of the damaging 1983 M[sub w] 6.8 Borah Peak, Idaho earthquake, which ruptured a central segment of the Lost River fault, has increased the awareness of seismic hazards in this portion of the Northern Basin and Range Province (NBR). As a result, comprehensive deterministic and probabilistic seismic hazard analyses were performed for the Idaho National Engineering Laboratory (INEL) which is located within the eastern Snake River Plain (ESRP) but adjacent to the NBR. In this region, the most significant seismic sources are three late-Quaternary NBR normal faults, the Lost River, Lemhi and Beaverhead faults, and ESRP volcanic zones. For each source, the maximum earthquake, source geometry, recurrence and their uncertainties were estimated and incorporated into the probabilistic analysis through the use of logic trees. Recent paleoseismic trenching of the Lost River and Lemhi faults and volcanic mapping in the ESRP provided much of the data necessary to characterize the most significant seismic sources. Issues such as fault segmentation, temporal clustering, the nature of fault termination, and the maximum magnitude and recurrence of volcanic zone earthquakes were evaluated in the hazard analyses. Deterministic and probabilistic ground motions were computed using both empirical and stochastic approaches. In the deterministic analysis, the southern segments of the Lemhi fault controlled the hazard at the INEL due to their proximity and potential to generate M[sub w] [approximately]7 earthquakes. In the estimation of deterministic ground motions, potential rupture scenarios were evaluated for a Lemhi earthquake. In the probabilistic analysis, the hazard is dominated by the ESRP random earthquake, and the Lemhi and Lost River faults. The difference in the results of the two analyses points out the uncertainties in assessing seismic hazards due to random earthquakes and in regions of large but infrequent earthquakes.

  7. 27 CFR 9.139 - Santa Lucia Highlands.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Road in a southeasterly direction for approximately 1 mile to the junction of River, Fort Romie and... the junction of Foothill and Paraiso Roads on the Soledad, California U.S.G.S. map. (8) Then...

  8. Sr, Nd, and Pb isotopes in Proterozoic intrusives astride the Grenville Front in Labrador - Implications for crustal contamination and basement mapping

    NASA Technical Reports Server (NTRS)

    Ashwal, L. D.; Wooden, J. L.; Emslie, R. F.

    1986-01-01

    Trace element and Pb, Sr, and Nd isotopic compositions of anorthosites and related rocks, and of younger mafic dikes from Harp Lake and Mealy Mountains in Labrador, Canada are estimated and compared. The effects of crustal component contaminants on the isotopic compositions of the dikes are investigated. The correlation between the isotopic data and the crustal contamination model is studied. It is observed that for Harp Lake the initial Sr ratios are higher and the Nd values are lower than Mealy samples, and the data do not correspond to the crustal contamination model; however, the Pb isotope data favor a crustal contamination model. It is noted that the Labrador segment of the Grenville Front appears to coincide with the southern margin of the Archean North Atlantic craton, and may represent a pre mid-Proterozoic suture.

  9. How does lean work in emergency care? A case study of a lean-inspired intervention at the Astrid Lindgren Children's hospital, Stockholm, Sweden

    PubMed Central

    2012-01-01

    Background There is growing interest in applying lean thinking in healthcare, yet, there is still limited knowledge of how and why lean interventions succeed (or fail). To address this gap, this in-depth case study examines a lean-inspired intervention in a Swedish pediatric Accident and Emergency department. Methods We used a mixed methods explanatory single case study design. Hospital performance data were analyzed using analysis of variance (ANOVA) and statistical process control techniques to assess changes in performance one year before and two years after the intervention. We collected qualitative data through non-participant observations, semi-structured interviews, and internal documents to describe the process and content of the lean intervention. We then analyzed empirical findings using four theoretical lean principles (Spear and Bowen 1999) to understand how and why the intervention worked in its local context as well as to identify its strengths and weaknesses. Results Improvements in waiting and lead times (19-24%) were achieved and sustained in the two years following lean-inspired changes to employee roles, staffing and scheduling, communication and coordination, expertise, workspace layout, and problem solving. These changes resulted in improvement because they: (a) standardized work and reduced ambiguity, (b) connected people who were dependent on one another, (c) enhanced seamless, uninterrupted flow through the process, and (d) empowered staff to investigate problems and to develop countermeasures using a "scientific method". Contextual factors that may explain why not even greater improvement was achieved included: a mismatch between job tasks, licensing constraints, and competence; a perception of being monitored, and discomfort with inter-professional collaboration. Conclusions Drawing on Spear and Bowen's theoretical propositions, this study explains how a package of lean-like changes translated into better care process management. It adds new knowledge regarding how lean principles can be beneficially applied in healthcare and identifies changes to professional roles as a potential challenge when introducing lean thinking there. This knowledge may enable health care organizations and managers in other settings to configure their own lean program and to better understand the reasons behind lean's success (or failure). PMID:22296919

  10. Laser cooling of a stored ion beam: A first step towards crystalline beams

    SciTech Connect

    Hangst, J.S.

    1992-09-01

    This report discusses: a brief introduction to storage rings; crystalline beams; laser cooling of ion beams; description of astrid-the experimental setup; first experiments with lithium 7 ion beam; experiments with erbium 166 ion beams; further experiments with lithium 7 ion beams; beam dynamics, laser cooling,and crystalline beams in astrid; possibilities for further study in astrid.

  11. Literacy in the Modern World.

    ERIC Educational Resources Information Center

    Hall, Geoff

    1999-01-01

    Reviews the following books: "The Politics of Writing," (Romy Clark, Roz Ivanic); "Literacy in Society," (Ruqaiya Hasan, Geoff Williams); "Text, Role, and Context: Developing Academic Literacies" (Ann M. Johns); "Changing Literacies" by (Colin Lankshear with James Paul Gee, Michele Knobel, Chris Searle); and "Vernacular Literacy: A Re-evaluation"…

  12. Romani Women and Popular Education

    ERIC Educational Resources Information Center

    Flecha, Ainhoa; Oliver, Esther

    2004-01-01

    The Romani community has traditionally been excluded from many spaces of participation, in many cases within the labour market and education. In this article, the authors analyse the situation of the Romani community, focusing especially on the reality of Romi who have been the catalysts of profound change for themselves as women and their…

  13. Differences in Expression of Key DNA Damage Repair Genes after Epigenetic-Induced BRCAness Dictate Synthetic Lethality with PARP1 Inhibition.

    PubMed

    Wiegmans, Adrian P; Yap, Pei-Yi; Ward, Ambber; Lim, Yi Chieh; Khanna, Kum Kum

    2015-10-01

    The triple-negative breast cancer (TNBC) subtype represents a cancer that is highly aggressive with poor patient outcome. Current preclinical success has been gained through synthetic lethality, targeting genome instability with PARP inhibition in breast cancer cells that harbor silencing of the homologous recombination (HR) pathway. Histone deacetylase inhibitors (HDACi) are a class of drugs that mediate epigenetic changes in expression of HR pathway genes. Here, we compare the activity of the pan-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA), the class I/IIa HDAC inhibitor valproic acid (VPA), and the HDAC1/2-specific inhibitor romidepsin (ROMI) for their capability to regulate DNA damage repair gene expression and in sensitizing TNBC to PARPi. We found that two of the HDACis tested, SAHA and ROMI, but not VPA, indeed inhibit HR repair and that RAD51, BARD1, and FANCD2 represent key proteins whose inhibition is required for HDACi-mediated therapy with PARP inhibition in TNBC. We also observed that restoration of BRCA1 function stabilizes the genome compared with mutant BRCA1 that results in enhanced polyploid population after combination treatment with HDACi and PARPi. Furthermore, we found that overexpression of the key HR protein RAD51 represents a mechanism for this resistance, promoting aberrant repair and the enhanced polyploidy observed. These findings highlight the key components of HR in guiding synthetic lethality with PARP inhibition and support the rationale for utilizing the novel combination of HDACi and PARPi against TNBC in the clinical setting. PMID:26294743

  14. Is "Gender-Sensitive Education" a Useful Concept for Educational Policy?

    ERIC Educational Resources Information Center

    Forde, Christine

    2014-01-01

    This article responds to Astrid Sinnes and Marianne Løken's article "Gendered education in a gendered world: Looking beyond cosmetic solutions to the gender gap in science" by exploring the idea of "gender-sensitive" education and its usefulness in educational policy. It draws on theoretical discussions of the concept of…

  15. Drawing of American ASTP crewmen searching for Soviet Soyuz spacecraft

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The American Apollo Soyuz Test Project (ASTP) crewmen search the skies for the Soviet Soyuz spacecraft in this humorous artwork by Cosmonaut Aleksey A. Leonov. Astronauts Vance D. Brand, Donald K. Slayton and Thomas P. Stafford (left to right) sit astride the Apollo spacecraft and Docking Module ready to lasso Soyuz. Leonov, an accomplished artist, specializes in painting on space subjects.

  16. The Lights Pre-Project: Implementation of the Project Approach with Children under 3 Years of Age

    ERIC Educational Resources Information Center

    Grzegorzewska, Katarzyna; Konieczna-Blicharz, Jagoda

    2011-01-01

    A group of children 18 months to 3 years old and their parents studied lights in a preschool program at the Astrid Lindgren Institute for Early Childhood Development in Poland. The goal of the preschool program is to help children gain positive social experience through safe and interesting contact with a new group of children and adults in the…

  17. Color Difference in Bering Sea Phytoplankton Blooms

    NASA Technical Reports Server (NTRS)

    2002-01-01

    There is considerable color variation in the phytoplankton blooms in the Bering Sea -- from the aquamarine west of Nunivak Island to the almost reddish patch west of St. Matthew Island to the green eddy astride the International dateline at 60 North latitude and 178 East longitude. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  18. Demystifying the Professoriate in Visual Art and Design Education

    ERIC Educational Resources Information Center

    Ward, Amber

    2014-01-01

    In the "Studies" article "Multiple Interruptions: Creative Encounters in Public Art and Public Pedagogy, A North--South Dialogue," Danny Wildemeersch and Astrid von Kotze write about the productive force of blurring institutional boundaries. They state: "As we negotiated our different relations of engagement with theory…

  19. 77 FR 41415 - Single-Ingredient, Immediate-Release Drug Products Containing Oxycodone for Oral Administration...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-13

    ... Administration (FDA) is correcting a notice that appeared in the Federal Register of July 6, 2012 (77 FR 40069... Spring, MD 20993-0002, 301- 796-3485, astrid.lopezgoldberg@fda.hhs.gov . SUPPLEMENTARY INFORMATION: In FR... are labeled for human use, and persons who manufacture or cause the manufacture or distribution...

  20. Arm posture score and arm movement during walking: a comprehensive assessment in spastic hemiplegic cerebral palsy.

    PubMed

    Riad, Jacques; Coleman, Scott; Lundh, Dan; Broström, Eva

    2011-01-01

    Patients with hemiplegic cerebral palsy often have noticeably deviant arm posture and decreased arm movement. Here we develop a comprehensive assessment method for the upper extremity during walking. Arm posture score (APS), deviation of shoulder flexion/extension, shoulder abduction/adduction, elbow flexion/extension and wrist flexion/extension were calculated from three-dimensional gait analysis. The APS is the root mean square deviation from normal, similar to Baker's Gait Profile Score (GPS) [1]. The total range of motion (ROM) was defined as the difference between the maximum and minimum position in the gait cycle for each variable. The arm symmetry, arm posture index (API) was calculated by dividing the APS on the hemiplegic side by that on the non-involved side, and the range of motion index (ROMI) by dividing the ROM on the hemiplegic side by that on the non-involved side. Using the APS, two groups were defined. Group 1 had minor deviations, with an APS under 9.0 and a mean of 6.0 (95% CI 5.0-7.0). Group 2 had more pronounced deviations, with an APS over 9.0 and a mean of 13.1 (CI 10.8-15.5) (p=0.000). Total ROM was 60.6 in group 1 and 46.2 in group 2 (p=0.031). API was 0.89 in group 1 and 1.70 in group 2 (p<0.001). ROMI was 1.15 in group 1 and 0.69 in group 2 (p=0.003). APS describes the amount of deviation, ROM provides additional information on movement pattern and the indices the symmetry. These comprehensive objective and dynamic measurements of upper extremity abnormality can be useful in following natural progression, evaluating treatment and making prognoses in several categories of patients. PMID:20971011

  1. Is `gender-sensitive education' a useful concept for educational policy?

    NASA Astrophysics Data System (ADS)

    Forde, Christine

    2014-06-01

    This article responds to Astrid Sinnes and Marianne Løken's article `Gendered education in a gendered world: Looking beyond cosmetic solutions to the gender gap in science' by exploring the idea of `gender-sensitive' education and its usefulness in educational policy. It draws on theoretical discussions of the concept of gender and of difference to consider ways in which `gender-sensitive' education might serve the task of promoting equality and justice.

  2. Chesapeake Bay, Potomac River

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The nation's capital lies astride the Potomac River (38.5N, 77.5W) at the head of the Potomac Estuary. Baltimore, MD, also in the scene, is connected to Washington by the Baltimore-Washington Parkway. The suburbs of both cities tend to cluster around the Washington and Baltimore Beltways. Most of the countryside in the eastern two-thirds of this scene is either heavily forested or is in farming, dairy operations or poultry production.

  3. Exotic minerals in 3,500 million year old rocks: Evidence for large meteorite impacts

    NASA Technical Reports Server (NTRS)

    Byerly, G. R.; Lowe, D. R.; Asaro, F.

    1988-01-01

    A relatively small area of mountainous terrain in southern Africa provides scientists from all over the world a look at what the surface of the earth was like three and a half billion years ago. The Barberton Mountains lie astride the borders of the Republic of South Africa, Mozambique, and the Kingdom of Swaziland. The discovery of several widely distributed deposits that were likely formed by major terrestrial impacts of large extraterrestrial bodies during this early period of earth's history is reported. The Barberton impact deposits are being studied by electron microscopy. The impact deposits were examined for minerals that show the effects of shock metamorphism or compositions unusual in terrestrial rocks.

  4. Acoustic streaming jets: A scaling and dimensional analysis

    SciTech Connect

    Botton, V. Henry, D.; Millet, S.; Ben-Hadid, H.; Garandet, J. P.

    2015-10-28

    We present our work on acoustic streaming free jets driven by ultrasonic beams in liquids. These jets are steady flows generated far from walls by progressive acoustic waves. As can be seen on figure 1, our set-up, denominated AStrID for Acoustic Streaming Investigation Device, is made of a water tank in which a 29 mm plane source emits continuous ultrasonic waves at typically 2 MHz. Our approach combines an experimental characterization of both the acoustic pressure field (hydrophone) and the obtained acoustic streaming velocity field (PIV visualization) on one hand, with CFD using an incompressible Navier-Stokes solver on the other hand.

  5. Solid rocket booster thermal radiation model, volume 1

    NASA Technical Reports Server (NTRS)

    Watson, G. H.; Lee, A. L.

    1976-01-01

    A solid rocket booster (SRB) thermal radiation model, capable of defining the influence of the plume flowfield structure on the magnitude and distribution of thermal radiation leaving the plume, was prepared and documented. Radiant heating rates may be calculated for a single SRB plume or for the dual SRB plumes astride the space shuttle. The plumes may be gimbaled in the yaw and pitch planes. Space shuttle surface geometries are simulated with combinations of quadric surfaces. The effect of surface shading is included. The computer program also has the capability to calculate view factors between the SRB plumes and space shuttle surfaces as well as surface-to-surface view factors.

  6. Clusters in storage rings

    SciTech Connect

    Hvelplund, P.; Andersen, J. U.; Hansen, K.

    1999-01-15

    Anions of fullerenes and small metal clusters have been stored in the storage rings ASTRID and ELISA. Decays on a millisecond time scale are due to electron emission from metastable excited states. For the fullerenes the decay curves have been interpreted in terms of thermionic emission quenched by radiative cooling. The stored clusters were heated by a Nd:YAG laser resulting in increased emission rates. With an OPO laser this effect was used to study the wavelength dependence of the absorption of light in hot C{sub 60}{sup -} ion molecules.

  7. PMSE and E-region plasma instability: In situ observations

    NASA Astrophysics Data System (ADS)

    Strelnikov, B.; Rapp, M.; Zecha, M.; Blix, T. A.; Friedrich, M.; Yeoman, T. K.

    2009-01-01

    From 29 June to July 6, 2003, the ROMA-Svalrak (Rocketborne Observations of the Middle Atmosphere at the Svalrak facilities) sounding rocket campaign took place at Ny-Alesund (Spitsbergen, geographical coord. 79oN, 12oE, geomagnetic coord. 76oN, 110oE). Three sounding rockets were launched to study neutral air turbulence and small scale plasma dynamics around polar mesosphere summer echoes (PMSE). During all three flights both PMSE and plasma instability events were observed. It is known that small-scale field aligned structures in the E-region plasma density can be created by unstable electromagnetic waves. The mechanism responsible for creating the structures causing radar echoes (PMSE) is believed to be neutral air turbulence in the presence of heavy charged particles. E-region plasma irregularities recorded during the last rocket flight (labeled RO-MI-03) were observed only during the upleg of the trajectory but not during the downleg. Also, on the upleg there was no clear spatial separation between PMSE and the plasma instability regions. In the current paper we consider this transition region in detail.

  8. Mechanisms for landscape evolution: Correlations between topography, lithology, erosion, and rock uplift in the central Nepalese Himalaya

    NASA Astrophysics Data System (ADS)

    Walsh, L. S.; Martin, A. J.; Ojha, T. P.; Fedenczuk, T.

    2009-12-01

    To investigate feedbacks between tectonics and erosion in the Himalaya-Tibet orogen we compare high resolution digital topography with detailed geologic maps of the Modi Khola valley in central Nepal. We examine the influence of lithologic contacts and structures on river steepness and concavity. The trace of the Bhanuwa fault, a large normal fault in Greater Himalayan rocks, coincides with the steepest location on the river profile where river steepness (ksn) reaches 884 m0.9. Transitions in ksn also occur at 1) the Romi fault, another normal fault, 2) within the Kuncha formation, 3) within Greater Himalayan rocks at the Formation I - Formation II boundary, and 4) between quartzite- and phyllite-rich parts of the Fagfog Formation. We assess mechanisms for ksn transitions on the Modi Khola by examining the influence of precipitation variability, glacial and landslide dams, tributary junctions, changes in lithology, and rock uplift on the topography. Although changes in lithology and/or landslide dams potentially explain all ksn extrema and transitions, these changes in river steepness consistently occur at normal faults suggesting possible recent motion on some of them. In detail, the Main Central thrust appears not to be the location of a major steepness change. Correlations of ksn with normal faults and lithologic contacts exhibit an important component of the landscape evolution process occurring in central Nepal and potentially other mountain belts.

  9. Crustal Magnetization Model of Maud Rise in the Southwest Indian Ocean

    NASA Technical Reports Server (NTRS)

    Kim, Hyung Rae; vanFrese, Ralph R. B.; Golynsky, Alexander V.; Taylor, Patrick T.; Kim, Jeong Woo

    2004-01-01

    We modeled the crustal magnetization for the Maud Rise in the south-west Indian Ocean off the coast of East Antarctica using magnetic observations from the Oersted satellite and near-surface surveys complied by the Antarctic Digital Magnetic Anomaly Project (ADMAP). A new inversion modeling scheme of the multi-altitude anomaly fields suggests that the magnetic effects due to crustal thickness variations and remanence involving the normal polarity Cretaceous Quiet Zone (KQZ) become increasingly dominant with altitude. The magnetic crustal thickness effects were modeled in the Oersted data using crustal thickness variations derived from satellite altitude gravity data. Remanent magnetization modeling of the residual Oersted and near-surface magnetic anomalies supports extending the KQZ eastwards to the Astrid Ridge. The remaining near-surface anomalies involve crustal features with relatively high frequency effects that are strongly attenuated at satellite altitudes. The crustal modeling can be extended by the satellite magnetic anomalies across the Indian Ocean Ridge for insight on the crustal properties of the conjugate Agulhas Plateau. The modeling supports the Jurassic reconstruction of Gondwana when the African Limpopo-Zambezi and East Antarctic Princess Astrid coasts were connected as part of a relatively demagnetized crustal block.

  10. Investigation of Nuclear Data Libraries with TRIPOLI-4 Monte Carlo Code for Sodium-cooled Fast Reactors

    NASA Astrophysics Data System (ADS)

    Lee, Y.-K.; Brun, E.

    2014-04-01

    The Sodium-cooled fast neutron reactor ASTRID is currently under design and development in France. Traditional ECCO/ERANOS fast reactor code system used for ASTRID core design calculations relies on multi-group JEFF-3.1.1 data library. To gauge the use of ENDF/B-VII.0 and JEFF-3.1.1 nuclear data libraries in the fast reactor applications, two recent OECD/NEA computational benchmarks specified by Argonne National Laboratory were calculated. Using the continuous-energy TRIPOLI-4 Monte Carlo transport code, both ABR-1000 MWth MOX core and metallic (U-Pu) core were investigated. Under two different fast neutron spectra and two data libraries, ENDF/B-VII.0 and JEFF-3.1.1, reactivity impact studies were performed. Using JEFF-3.1.1 library under the BOEC (Beginning of equilibrium cycle) condition, high reactivity effects of 808 ± 17 pcm and 1208 ± 17 pcm were observed for ABR-1000 MOX core and metallic core respectively. To analyze the causes of these differences in reactivity, several TRIPOLI-4 runs using mixed data libraries feature allow us to identify the nuclides and the nuclear data accounting for the major part of the observed reactivity discrepancies.

  11. Ways of improvement for the materials of sodium cooled fast reactors

    SciTech Connect

    Horowitz, E.

    2012-07-01

    The French sodium cooled prototype reactor ASTRID will take into account 'Generation IV' requirements, especially a long operational life-time (60 years) and a high efficiency. The good behavior of austenitic steel AISI316L(N), should be confirmed for a use, in moderately irradiated and unirradiated parts of ASTRID. Parts recovered from dismantled French sodium-cooled reactors will be characterized. Further experiments must be carried out concerning ageing of these components. Other materials will be chosen for fuel wrapping and cladding, in order to reduce creep and swelling under irradiation, (either conventional, or oxide-dispersed strengthened steels (ODSS). Corrosion of ODSS in the presence of sodium needs a serious assessment The lifetime of primary pumps components made of Duplex steels should also be assessed. The disruptions in steam generator tubes should be minimized and controlled; therefore, optimised designs and geometries must be established before defining the corresponding materials. Either Modified 9Cr1Mo or Incoloy 800H, might be candidates;it will be necessary to check whether austenitic steels are compatible with Modified 9Cr1Mo or Incoloy 800H in the same circuit. For all materials, the best manufacturing processes must be combined with thermal, mechanical treatments; calculations of phase diagrams (CALPHAD) might be used to optimise both treatments and chemical compositions. (authors)

  12. Dynamical analysis of innovative core designs facing unprotected transients with the MAT5 DYN code

    SciTech Connect

    Darmet, G.; Massara, S.

    2012-07-01

    Since 2007, advanced Sodium-cooled Fast Reactors (SFR) are investigated by CEA, AREVA and EDF in the framework of a joint French collaboration. A prototype called ASTRID, sets out to demonstrate progress made in SFR technology, is due to operate in the years 2020's. The modeling of unprotected transients by computer codes is one of the key safety issues in the design approach to such SFR systems. For that purpose, the activity on CATHARE, which is the reference code for the transient analysis of ASTRID, has been strengthened during last years by CEA. In the meantime, EDF has developed a simplified and multi-channel code, named MAT5 DYN, to analyze and validate innovative core designs facing protected and unprotected transients. First, the paper consists in a description of MAT5 DYN: a code based on the existing code MAT4 DYN including major improvements on geometry description and physical modeling. Second, two core designs based on the CFV core design developed at CEA are presented. Then, the dynamic response of those heterogeneous cores is analyzed during unprotected loss of flow (ULOF) transient and unprotected transient of power (UTOP). The results highlight the importance of the low void core effect specific to the CFV design. Such an effect, when combined with a sufficient primary pump halving time and an optimized cooling group scheme, allows to delay (or, possibly, avoid) the sodium boiling onset during ULOF accidents. (authors)

  13. Coincidence or not? Interconnected gas/fluid migration and ocean-atmosphere oscillations in the Levant Basin

    NASA Astrophysics Data System (ADS)

    Lazar, Michael; Lang, Guy; Schattner, Uri

    2016-03-01

    A growing number of studies on shallow marine gas/fluid systems from across the globe indicate their abundance throughout geological epochs. However, these episodic events have not been fully integrated into the fundamental concepts of continental margin development, which are thought to be dictated by three elements: tectonics, sedimentation and eustasy. The current study focuses on the passive sector of the Levant Basin on the eastern Mediterranean continental margin where these elements are well constrained, in order to isolate the contribution of gas/fluid systems. Single-channel, multichannel and 3D seismic reflection data are interpreted in terms of variance, chaos, envelope and sweetness attributes. Correlation with the Romi-1 borehole and sequence boundaries constrains interpretation of seismic stratigraphy. Results show a variety of fluid- or gas-related features such as seafloor and subsurface pockmarks, volumes of acoustic blanking, bright spots, conic pinnacle mounds, gas chimneys and high sweetness zones that represent possible secondary reservoirs. It is suggested that gas/fluid migrate upwards along lithological conduits such as falling-stage systems tracts and sequence boundaries during both highstands and lowstands. In all, 13 mid-late Pleistocene sequence boundaries are accompanied by independent evidence of 13 eustatic sea-level drops. Whether this connection is coincidental or not requires further research. These findings fill gaps between previously reported sporadic appearances throughout the Levant Basin and margin and throughout geological time from the Messinian until the present day, and create a unified framework for understanding the system as a whole. Repetitive appearance of these features suggests that their role in the morphodynamics of continental margins is more important than previously thought and thus may constitute one of the key elements of continental margin development.

  14. Portable sensor technology for rotational ground motions

    NASA Astrophysics Data System (ADS)

    Bernauer, Felix; Wassermann, Joachim; Guattari, Frédéric; Igel, Heiner

    2016-04-01

    In this contribution we present performance characteristics of a single component interferometric fiber-optic gyroscope (IFOG). The prototype sensor is provided by iXBlue, France. It is tested in the framework of the European Research Council Project, ROMY (Rotational motions - a new observable for seismology), on its applicability as a portable and field-deployable sensor for rotational ground motions. To fully explore the benefits of this new seismic observable especially in the fields of vulcanology, ocean generated noise and geophysical exploration, such a sensor has to fulfill certain requirements regarding portability, power consumption, time stamping stability and dynamic range. With GPS-synchronized time stamping and miniseed output format, data acquisition is customized for the use in seismology. Testing time stamping accuracy yields a time shift of less than 0.0001 s and a correlation coefficient of 0.99 in comparison to a commonly used data acquisition system, Reftek 120. Sensor self-noise is below 5.0 ṡ 10‑8 rads‑1Hz‑1/2 for a frequency band from 0.001 Hz to 5.0 Hz. Analysis of Allan deviation shows an angle random walk of 3.5 ṡ 10‑8 rads‑1Hz‑1/2. Additionally, the operating range diagram is shown and ambient noise analysis is performed. The sensitivity of sensor self-noise to variations in surrounding temperature and magnetic field is tested in laboratory experiments. With a power consumption of less than 10 W, the whole system (single component sensor + data acquisition) is appropriate for field use with autonomous power supply.

  15. Coincidence or not? Interconnected gas/fluid migration and ocean-atmosphere oscillations in the Levant Basin

    NASA Astrophysics Data System (ADS)

    Lazar, Michael; Lang, Guy; Schattner, Uri

    2016-08-01

    A growing number of studies on shallow marine gas/fluid systems from across the globe indicate their abundance throughout geological epochs. However, these episodic events have not been fully integrated into the fundamental concepts of continental margin development, which are thought to be dictated by three elements: tectonics, sedimentation and eustasy. The current study focuses on the passive sector of the Levant Basin on the eastern Mediterranean continental margin where these elements are well constrained, in order to isolate the contribution of gas/fluid systems. Single-channel, multichannel and 3D seismic reflection data are interpreted in terms of variance, chaos, envelope and sweetness attributes. Correlation with the Romi-1 borehole and sequence boundaries constrains interpretation of seismic stratigraphy. Results show a variety of fluid- or gas-related features such as seafloor and subsurface pockmarks, volumes of acoustic blanking, bright spots, conic pinnacle mounds, gas chimneys and high sweetness zones that represent possible secondary reservoirs. It is suggested that gas/fluid migrate upwards along lithological conduits such as falling-stage systems tracts and sequence boundaries during both highstands and lowstands. In all, 13 mid-late Pleistocene sequence boundaries are accompanied by independent evidence of 13 eustatic sea-level drops. Whether this connection is coincidental or not requires further research. These findings fill gaps between previously reported sporadic appearances throughout the Levant Basin and margin and throughout geological time from the Messinian until the present day, and create a unified framework for understanding the system as a whole. Repetitive appearance of these features suggests that their role in the morphodynamics of continental margins is more important than previously thought and thus may constitute one of the key elements of continental margin development.

  16. Coronal disturbances and their terrestrial effects /Tutorial Lecture/

    NASA Technical Reports Server (NTRS)

    Rust, D. M.

    1983-01-01

    An assessment is undertaken of recent approaches to the prediction of the interplanetary consequences of coronal disturbances, with attention to the relationships of shocks and energetic particles to coronal transients, of proton events to gamma-ray and microwave bursts, of geomagnetic storms to filament eruptions, and of solar wind increases to the flare site magnetic field direction. A discussion is given concerning the novel phenomenon of transient coronal holes, which appear astride the long decay enhancements of 2-50 A X-ray emission following H-alpha filament eruptions. These voids in the corona are similar to long-lived coronal holes, which are the sources of high speed solar wind streams. The transient coronal holes may also be associated with transient solar wind speed increases.

  17. Laser-cooled continuous ion beams

    SciTech Connect

    Schiffer, J.P.; Hangst, J.S.; Nielsen, J.S.

    1995-08-01

    A collaboration with a group in Arhus, Denmark, using their storage ring ASTRID, brought about better understanding of ion beams cooled to very low temperatures. The longitudinal Schottky fluctuation noise signals from a cooled beam were studied. The fluctuation signals are distorted by the effects of space charge as was observed in earlier measurements at other facilities. However, the signal also exhibits previously unobserved coherent components. The ions` velocity distribution, measured by a laser fluorescence technique suggests that the coherence is due to suppression of Landau damping. The observed behavior has important implications for the eventual attainment of a crystalline ion beam in a storage ring. A significant issue is the transverse temperature of the beam -- where no direct diagnostics are available and where molecular dynamics simulations raise interesting questions about equilibrium.

  18. Venus: Preliminary topographic and surface imaging results from the Pioneer orbiter

    USGS Publications Warehouse

    Pettengill, G.H.; Ford, P.G.; Brown, W.E.; Kaula, W.M.; Masursky, H.; Eliason, E.; McGill, G.E.

    1979-01-01

    Three large Venus surface features, identified previously in images obtained from Earth-based radar observations, are shown by the Pioneer Venus radar mapper to be elevateds to 10 kilometers above the surrounding terrain. Two of these features, one bright and the other dark, lie adjacent to each other astride the 65??N parallel between longitudes 310??E and 10??E. The combined region forms a huge tectonically uplifted plateau, surmounted by radar-bright ridges that may have either a volcanic or tectonic origin. The third feature, located at 30??N, 283??E, is radar-bright and may consist of volcanic material extruded along a fault zone. A first radar-scattering image, compiled from data obtained by the mapper in its imaging mode, shows a region north of the equator; several circular depressions seen in this area may result from meteoritic impact.

  19. Geology and ground-water resources of the Walla Walla River basin Washington-Oregon

    USGS Publications Warehouse

    Newcomb, R.C.

    1965-01-01

    The Walla Walla River, whose drainage basin of about 1,330 square miles lies astride the Washington-Oregon boundary, drains westward to empty into the Columbia River. The basin slopes from the 5,000-foot crest of the Blue Mountains through a structural and topographic basin to the terraced lands adjoining the Columbia River at an altitude of about 340 feet. The main unit of the topographic basin is the valley plain, commonly called the Walla Walla Valley, which descends from about 1,500 feet at the foot of the mountain slopes to about 500 feet in altitude where the river cuts through the bedrock ridge near Divide. In the Blue Mountains the streams flow in rockbound canyons. Beyond the canyons, near Milton-Freewater and Walla Walla, they pass onto the broad alluvial fans and the terrace lands of the valley.

  20. Meeting report for "OddPols" 2014: the odds invite an even.

    PubMed

    Roy-Engel, Astrid M

    2015-02-01

    The Ninth International Biennial Conference on RNA Polymerases I and III (the "OddPols") was held on June 19-21, 2014 at the University of Michigan, Ann Arbor, USA. Sponsored by New England Biolabs, the Cayman Chemical Company, the Rackham Graduate School and the University of Michigan Health System, and organized by David Engelke, Craig Pikaard, Lawrence Rothblum, Andrzej Wierzbicki and Astrid Engel. This year at the conference, the "odds" were increased by expanding the usual topics on the advances in RNA polymerases I and III research to include presentations on RNA polymerase IV and V. The keynote speaker, Craig Pikaard, opened the meeting with his presentation entitled "Five nuclear multisubunit RNA polymerases". The meeting drew attendees from fourteen countries that shared their research discoveries through oral and poster presentations. The talks were organized into 11 sessions covering seven distinct topics. Here we present some of the highlights from the meeting using summaries provided by the participants. PMID:25445280

  1. Photoionization of the Ne-like Si4+ ion in ground and metastable states in the 110-184-eV photon energy range

    NASA Astrophysics Data System (ADS)

    Bizau, J.-M.; Mosnier, J.-P.; Kennedy, E. T.; Cubaynes, D.; Wuilleumier, F. J.; Blancard, C.; Champeaux, J.-P.; Folkmann, F.

    2009-03-01

    We present measurements of the absolute photoionization cross section of the neonlike Si4+ ion over the 110-184 eV photon energy range. The measurements were performed using two independent merged-beam setups at the super-ACO and ASTRID synchrotron-radiation facilities, respectively. Signals produced in the photoionization of the 2p subshell of the Si4+ ion both from the 2p6S10 ground state and the 2p53sP30,2 metastable levels were observed. Calculations of the 2p photoionization cross sections were carried out using a multi-configuration Dirac-Fock code. They give results in good agreement with the measured spectra. Comparison with other available theoretical results is also presented.

  2. In-drop capillary spooling of spider capture thread inspires hybrid fibers with mixed solid–liquid mechanical properties

    NASA Astrophysics Data System (ADS)

    Elettro, Hervé; Neukirch, Sébastien; Vollrath, Fritz; Antkowiak, Arnaud

    2016-05-01

    An essential element in the web-trap architecture, the capture silk spun by ecribellate orb spiders consists of glue droplets sitting astride a silk filament. Mechanically this thread presents a mixed solid–liquid behavior unknown to date. Under extension, capture silk behaves as a particularly stretchy solid, owing to its molecular nanosprings, but it totally switches behavior in compression to now become liquid-like: It shrinks with no apparent limit while exerting a constant tension. Here, we unravel the physics underpinning the unique behavior of this ”liquid wire” and demonstrate that its mechanical response originates in the shape-switching of the silk filament induced by buckling within the droplets. Learning from this natural example of geometry and mechanics, we manufactured programmable liquid wires that present previously unidentified pathways for the design of new hybrid solid–liquid materials.

  3. Evolution of Ionospheric Convection during a Double Transpolar Arc Phenomenon on February 11, 1999

    NASA Technical Reports Server (NTRS)

    Narita, Y.; Maezawa, K.; Spann, J. F.; Parks, G. K.; Marklund, G. T.; Kullen, A.; Ivchenko, N.; Greenwald, R. A.; Sato, N.; Yamagishi, H.; Six, N. Frank (Technical Monitor)

    2002-01-01

    An evolution of ionospheric convection was studied for a double transpolar arc phenomenon on February 11, 1999. While one transpolar arc split from the auroral oval in the morning sector and drifted duskward, another arc appeared in the evening sector. The convection was investigated with three velocity data sets: E B drift velocities from the ASTRID-2 satellite; Ion Driftmeter data from the DMSP satellites; and Doppler-shift data from the Super-DARN radars. We inferred convection cells from these data sets and found that the number of convection cells changed from three to four as the dominance of IMF changed from a negative By to a positive Bz. Our result suggests that the ionospheric convection that has been so far discussed for various conditions of IMF may be applied even to the cases accompanied by transpolar arcs.

  4. Nursing researchers' modifications of Ricoeur's hermeneutic phenomenology.

    PubMed

    Singsuriya, Pagorn

    2015-12-01

    Paul Ricoeur's hermeneutic phenomenology has proved to be very helpful in guiding nursing researchers' qualitative analysis of interview transcripts. Modifying Ricoeur's philosophy, a number of nursing researchers have developed their own interpretive methods and shared them, along with their experience, with research community. Major contributors who published papers directly presenting their modifications of Ricoeur's theory include Rene Geanellos (2000), Lena Wiklund, Lisbet Lindholm and Unni Å. Lindström (2002), Anders Lindseth and Astrid Norberg (2004) and Pia Sander Dreyer and Birthe D Pedersen (2009). The aim of this article was to delineate differences among these methods. Descriptive presentation of each method side by side makes clear the differences among them. In addition, Ricoeur's hermeneutic theory is portrayed and compared with the modifications. It is believed that differences that are found can stimulate further thoughts on how to apply Ricoeur's theory in qualitative research in nursing. PMID:25808423

  5. Methodology and tools for source term assessment in case of emergency.

    PubMed

    Herviou, Karine; Calmtorp, Christer

    2004-01-01

    By looking at the power plant state of fission product barriers and critical safety systems, the magnitude of a potential radioactive release could be predicted in a timely manner to allow emergency response to be executed even before the occurrence of a release. This is the perspective in which the development of ASTRID methodology and tool is performed. The methodology maps out, for several reactor types as well as reactor containments, relevant process parameters and indicators, what and how to calculate and a structured way to summarise and conclude on potential source term and likely time projections. A computer tool is proposed to support the methodology, to suite different user situations, both on-site and off-site as well as size of staff, priority and work order. The output from such an assessment is intended to, first, give bases for decisions on necessary urgent protective actions pre-release, and, second, an input for the sophisticated dispersion calculation codes. PMID:15238656

  6. Secular evolution of asteroid families: the role of Ceres

    NASA Astrophysics Data System (ADS)

    Novaković, Bojan; Tsirvoulis, Georgios; Marò, Stefano; Đošović, Vladimir; Maurel, Clara

    2016-01-01

    We consider the role of the dwarf planet Ceres on the secular dynamics of the asteroid main belt. Specifically, we examine the post impact evolution of asteroid families due to the interaction of their members with the linear nodal secular resonance with Ceres. First, we find the location of this resonance and identify which asteroid families are crossed by its path. Next, we summarize our results for three asteroid families, namely (1726) Hoffmeister, (1128) Astrid and (1521) Seinajoki which have irregular distributions of their members in the proper elements space, indicative of the effect of the resonance. We confirm this by performing a set of numerical simulations, showcasing that the perturbing action of Ceres through its linear nodal secular resonance is essential to reproduce the actual shape of the families.

  7. In-drop capillary spooling of spider capture thread inspires hybrid fibers with mixed solid-liquid mechanical properties.

    PubMed

    Elettro, Hervé; Neukirch, Sébastien; Vollrath, Fritz; Antkowiak, Arnaud

    2016-05-31

    An essential element in the web-trap architecture, the capture silk spun by ecribellate orb spiders consists of glue droplets sitting astride a silk filament. Mechanically this thread presents a mixed solid-liquid behavior unknown to date. Under extension, capture silk behaves as a particularly stretchy solid, owing to its molecular nanosprings, but it totally switches behavior in compression to now become liquid-like: It shrinks with no apparent limit while exerting a constant tension. Here, we unravel the physics underpinning the unique behavior of this "liquid wire" and demonstrate that its mechanical response originates in the shape-switching of the silk filament induced by buckling within the droplets. Learning from this natural example of geometry and mechanics, we manufactured programmable liquid wires that present previously unidentified pathways for the design of new hybrid solid-liquid materials. PMID:27185930

  8. Development and application of modeling tools for sodium fast reactor inspection

    SciTech Connect

    Le Bourdais, Florian; Marchand, Benoît; Baronian, Vahan

    2014-02-18

    To support the development of in-service inspection methods for the Advanced Sodium Test Reactor for Industrial Demonstration (ASTRID) project led by the French Atomic Energy Commission (CEA), several tools that allow situations specific to Sodium cooled Fast Reactors (SFR) to be modeled have been implemented in the CIVA software and exploited. This paper details specific applications and results obtained. For instance, a new specular reflection model allows the calculation of complex echoes from scattering structures inside the reactor vessel. EMAT transducer simulation models have been implemented to develop new transducers for sodium visualization and imaging. Guided wave analysis tools have been developed to permit defect detection in the vessel shell. Application examples and comparisons with experimental data are presented.

  9. In-drop capillary spooling of spider capture thread inspires hybrid fibers with mixed solid–liquid mechanical properties

    PubMed Central

    Elettro, Hervé; Neukirch, Sébastien; Vollrath, Fritz; Antkowiak, Arnaud

    2016-01-01

    An essential element in the web-trap architecture, the capture silk spun by ecribellate orb spiders consists of glue droplets sitting astride a silk filament. Mechanically this thread presents a mixed solid–liquid behavior unknown to date. Under extension, capture silk behaves as a particularly stretchy solid, owing to its molecular nanosprings, but it totally switches behavior in compression to now become liquid-like: It shrinks with no apparent limit while exerting a constant tension. Here, we unravel the physics underpinning the unique behavior of this ”liquid wire” and demonstrate that its mechanical response originates in the shape-switching of the silk filament induced by buckling within the droplets. Learning from this natural example of geometry and mechanics, we manufactured programmable liquid wires that present previously unidentified pathways for the design of new hybrid solid–liquid materials. PMID:27185930

  10. Development and application of modeling tools for sodium fast reactor inspection

    NASA Astrophysics Data System (ADS)

    Le Bourdais, Florian; Marchand, Benoît; Baronian, Vahan

    2014-02-01

    To support the development of in-service inspection methods for the Advanced Sodium Test Reactor for Industrial Demonstration (ASTRID) project led by the French Atomic Energy Commission (CEA), several tools that allow situations specific to Sodium cooled Fast Reactors (SFR) to be modeled have been implemented in the CIVA software and exploited. This paper details specific applications and results obtained. For instance, a new specular reflection model allows the calculation of complex echoes from scattering structures inside the reactor vessel. EMAT transducer simulation models have been implemented to develop new transducers for sodium visualization and imaging. Guided wave analysis tools have been developed to permit defect detection in the vessel shell. Application examples and comparisons with experimental data are presented.

  11. R and D program for French sodium fast reactor: On the description and detection of sodium boiling phenomena during sub-assembly blockages

    SciTech Connect

    Vanderhaegen, M.; Paumel, K.; Seiler, J. M.; Tourin, A.; Jeannot, J. P.; Rodriguez, G.

    2011-07-01

    In support of the French ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) reactor program, which aims to demonstrate the industrial applicability of sodium fast reactors with an increased level of safety demonstration and availability compared to the past French sodium fast reactors, emphasis is placed on reactor instrumentation. It is in this framework that CEA studies continuous core monitoring to detect as early as possible the onset of sodium boiling. Such a detection system is of particular interest due to the rapid progress and the consequences of a Total Instantaneous Blockage (TIB) at a subassembly inlet, where sodium boiling intervenes in an early phase. In this paper, the authors describe all the particularities which intervene during the different boiling stages and explore possibilities for their detection. (authors)

  12. In vessel detection of delayed neutron emitters from clad failure in sodium cooled nuclear reactors: An estimation of the signal

    NASA Astrophysics Data System (ADS)

    Filliatre, P.; Jammes, C.; Chapoutier, N.; Jeannot, J.-P.; Jadot, F.; Batail, R.; Verrier, D.

    2014-04-01

    The detection of clad failures is mandatory in sodium-cooled fast neutron reactors in compliance with the "clean sodium" concept. An in-vessel detection system, sensitive to delayed neutrons from fission products released into the primary coolant by failures, partially tested in SUPERPHENIX, is foreseen in current SFR projects in order to reduce significantly the delay before an alarm is issued. In this paper, an estimation of the signal received by such a system in case of a failure is derived, taking the French project ASTRID as a working example. This failure induced signal is compared to that of the contribution of the neutrons from the core itself. The sensitivity of the system is defined in terms of minimal detectable surface of clad failure. Possible solutions to improve this sensitivity are discussed, involving either the sensor itself, or the hydraulic design of the vessel in the early stage of the reactor conception.

  13. New JEFF-3.2 Sodium Neutron Induced Cross-sections Evaluation for Neutron Fast Reactors Applications: from 0 to 20 MeV

    NASA Astrophysics Data System (ADS)

    Archier, P.; Noguère, G.; De Saint Jean, C.; Plompen, A. J. M.; Rouki, C.

    2014-04-01

    In the framework of the ASTRID project, a new 23Na evaluation, containing re-evaluated nuclear data and associated covariances, has been prepared to be submitted for the future JEFF-3.2 library. This work has been motivated mainly because the current JEFF-3.1.1 sodium evaluation showed large differences with microscopic measurements and does not have covariances data. Recent experimental data from IRMM and high resolution measurements from Larson have been simultaneously analyzed with the data assimilation code CONRAD and a good agreement with the evaluated cross-sections has been achieved. Experimental systematic uncertainties have been propagated to the nuclear reaction model parameters in order to produce a coherent set of covariance data. Several figures are provided in this paper to illustrate the new features of this evaluation.

  14. STS-40 Mission Specialist (MS) Seddon on ergometer conducts Exp. No. 066

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Astride the bicycle ergometer, STS-40 Mission Specialist (MS) M. Rhea Seddon breathes into the cardiovascular rebreathing unit (CRU) during the exercise phase of Experiment No. 066, Inflight Study of Cardiovascular Deconditioning. It focuses on the deconditioning of the heart and lungs and changes in cardiopulmonary function that occur upon return to Earth. By using noninvasive techniques of prolonged expiration and rebreathing, investigators can determine the amount of blood pumped out of the heart (cardiac output), the ease with which blood flows through all the vessels (total peripheral resistance), oxygen used and carbon dioxide released by the body, and lung function and volume changes. Measurements are made both while crewmembers are resting and while they pedal the ergometer. Shirtless, MS James P. Bagian conducts a second experiment in the background.

  15. The Crustal Dichotomy Boundary West of Tempe Terra: Speculation on Where it Lies Beneath Alba Patera Based on Mola Topography

    NASA Technical Reports Server (NTRS)

    Frey, H.; Roark, J.; Sakimoto, S.; McGovern, P.

    1999-01-01

    MOLA gridded data based on profiles collected during the Aerobraking Hiatus and Science Phasing Operations suggest the crustal dichotomy boundary west of Tempe continues beneath Alba volcanics, at least to 105 W at about 50 N. A broad shelf-like region in the Alba units is continuous with a similar region of Tempe in which Hesperian volcanics overlie Noachian cratered terrain. Perspective views show significant changes in the sloping character of the flanks of Alba east and west of 105W, with much more continuous steep topography to the west. We suggest that Alba sits astride the ancient crustal dichotomy boundary, not adjacent to it, and that its eastern half lies on old cratered terrain. If true, this would significantly affect the estimate of Alba volcanics volumes, and might also explain some of the observed asymmetries in the structure and the distribution of faults associated with this immense feature.

  16. Mars Orbiting Plasma Surveyor (MOPS)

    NASA Astrophysics Data System (ADS)

    Barabash, S.; Andre, M.; Blomberg, L. G.; Lundin, R.; Marklund, G. T.; Rathsman, P.; von Scheele, F.; Wahlund, J.-E.

    Mars Orbiting Plasma Surveyor (MOPS) S. Barabash (1), M. André (2), L. G. Blomberg (3), R. Lundin (1),G. T. Marklund (3), P. Rathsman (4), F. von Schéele (4), J.-E. Wahlund (2) (1) Swedish Institute of Space Physics, Kiruna, Sweden (stas@irf.se) (2) Swedish Institute of Space Physics, Uppsala, Sweden (3) Royal Institute of Technology, Department of Space and Plasma Physics , Stockholm, Sweden (4) Swedish Space Corporation, Solna, Sweden Mars Orbiting Plasma Surveyor (MOPS) is a microsatellite mission focused on studies of the near - Mars environment and the planet - solar wind interaction. The recent findings by the ESA Mars Express mission further highlighted the complexity of the processes taking place at the planet resulting from the solar wind interaction that strongly affect the planet's atmosphere. However, despite many previous Martian missions carrying different types of space plasma experiments, a comprehensive investigation including simultaneous measurements of particles, fields, and waves has never been performed. We propose a spinning spacecraft of a mass of 50-80 kg with a 10 kg payload which can "hitchhike" on another platform until Mars orbit insertion and then be released into a suitable orbit. The spacecraft design is based on the experience gained in very successful Swedish space plasma missions, Viking, Freja, Astrid -1, and Astrid - 2. In the present mission design, the MOPS spacecraft is equipped with its own 1m high gain antenna for direct communication with the Earth. The payload includes a wave experiment with wire booms, magnetometer with a rigid boom, electron and ion energy spectrometers and an ion mass analyser. An energetic neutral atom imager and an UV photometer may complete the core payload.

  17. Glacial atmospheric phosphorus deposition

    NASA Astrophysics Data System (ADS)

    Kjær, Helle Astrid; Dallmayr, Remi; Gabrieli, Jacopo; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Svensson, Anders; Vallelonga, Paul

    2016-04-01

    Phosphorus in the atmosphere is poorly studied and thus not much is known about atmospheric phosphorus and phosphate transport and deposition changes over time, though it is well known that phosphorus can be a source of long-range nutrient transport, e.g. Saharan dust transported to the tropical forests of Brazil. In glacial times it has been speculated that transport of phosphorus from exposed shelves would increase the ocean productivity by wash out. However whether the exposed shelf would also increase the atmospheric load to more remote places has not been investigated. Polar ice cores offer a unique opportunity to study the atmospheric transport of aerosols on various timescales, from glacial-interglacial periods to recent anthropogenic influences. We have for the first time determined the atmospheric transport of phosphorus to the Arctic by means of ice core analysis. Both total and dissolved reactive phosphorus were measured to investigate current and past atmospheric transport of phosphorus to the Arctic. Results show that glacial cold stadials had increased atmospheric total phosphorus mass loads of 70 times higher than in the past century, while DRP was only increased by a factor of 14. In the recent period we find evidence of a phosphorus increase over the past 50 yrs in ice cores close to human occupation likely correlated to forest fires. References: Kjær, Helle Astrid, et al. "Continuous flow analysis method for determination of dissolved reactive phosphorus in ice cores." Environmental science & technology 47.21 (2013): 12325-12332. Kjær, Helle Astrid, et al. "Greenland ice cores constrain glacial atmospheric fluxes of phosphorus." Journal of Geophysical Research: Atmospheres120.20 (2015).

  18. Geothermal potential of Caledonian granites in Ireland and the Isle of Man: Implications from hydrothermal alteration

    NASA Astrophysics Data System (ADS)

    Fritschle, Tobias; Daly, J. Stephen; Whitehouse, Martin J.; Buhre, Stephan; McConnell, Brian; The Iretherm Team

    2015-04-01

    Ordovician to Devonian (Caledonian) granites are common in the Iapetus Suture Zone (ISZ) in Ireland and Britain. Some of these, e.g., the buried Kentstown and Glenamaddy granites, are situated beneath Upper Palaeozoic sedimentary basins, and hence are potential geothermal targets. Numerous granites of similar age and related origin (Fritschle et al., 2014) are exposed astride the ISZ. They are considered to be analogous to the buried ones, and their geochemical characteristics are used as a proxy for the buried granites as samples from deep drilling are naturally limited. The whole-rock geochemistry of nine granite intrusions (71 samples, including both hydrothermally altered and unaltered samples) varies significantly, but with no obvious geographical control. The granites are S- and I-Types with ASI (Aluminium Saturation Index) between 0.7 - 1.4. Average heat production rates range from 1.4 μW/m³ for the Leinster Granite to 4.9 μW/m³ for the Drogheda Granite (Fritschle et al., 2015). The heat-producing elements uranium (U), thorium (Th) and potassium (K) and calculated heat production rates generally correlate positively with niobium and rubidium concentrations. However, S-Type compared to I-Type granites show elevated abundances in rubidium (>130 ppm) and usually have a lower Th/U ratio. Altered samples tend to have a higher Th/U ratio compared to unaltered ones. Within individual plutons trends of decreasing heat production rates with increasing Th/U ratios were observed. This trend is attributed to the hydrothermal redistribution of the mobile heat-producing element uranium. This is also implied by uranium-enrichment in hydrothermally generated Ca and Si-veinlets. Metasomatic processes such as hydrothermal alteration appear capable of significantly redistributing mobile elements such as uranium. Hence, these processes may act as a major mechanism controlling the granite's heat production budget, often shaping a pluton's geothermal exploitation potential

  19. Crustal structure and tectonic provinces of the Riiser-Larsen Sea area (East Antarctica): results of geophysical studies

    NASA Astrophysics Data System (ADS)

    Leitchenkov, G.; Guseva, J.; Gandyukhin, V.; Grikurov, G.; Kristoffersen, Y.; Sand, M.; Golynsky, A.; Aleshkova, N.

    2008-06-01

    About 16,000 km of multichannel seismic (MCS), gravity and magnetic data and 28 sonobuoys were acquired in the Riiser-Larsen Sea Basin and across the Gunnerus and Astrid Ridges, to study their crustal structure. The study area has contrasting basement morphologies and crustal thicknesses. The crust ranges in thickness from about 35 km under the Riiser-Larsen Sea shelf, 26 28 km under the Gunnerus Ridge, 12 17 km under the Astrid Ridge, and 9.5 10 km under the deep-water basin. A 50-km-wide block with increased density and magnetization is modeled from potential field data in the upper crust of the inshore zone and is interpreted as associated with emplacement of mafic intrusions into the continental margin of the southern Riiser-Larsen Sea. In addition to previously mapped seafloor spreading magnetic anomalies in the western Riiser-Larsen Sea, a linear succession from M2 to M16 is identified in the eastern Riiser-Larsen Sea. In the southwestern Riiser-Larsen Sea, a symmetric succession from M24B to 24n with the central anomaly M23 is recognized. This succession is obliquely truncated by younger lineation M22 M22n. It is proposed that seafloor spreading stopped at about M23 time and reoriented to the M22 opening direction. The seismic stratigraphy model of the Riiser-Larsen Sea includes five reflecting horizons that bound six seismic units. Ages of seismic units are determined from onlap geometry to magnetically dated oceanic basement and from tracing horizons to other parts of the southern Indian Ocean. The seaward edge of stretched and attenuated continental crust in the southern Riiser-Larsen Sea and the landward edge of unequivocal oceanic crust are mapped based on structural and geophysical characteristics. In the eastern Riiser-Larsen Sea the boundary between oceanic and stretched continental crust is better defined and is interpreted as a strike-slip fault lying along a sheared margin.

  20. Holographic Interferometry Applied At Subfreezing Temperatures: Study Of Damage In Concrete Exposed To Frost Action

    NASA Astrophysics Data System (ADS)

    Rastogi, Pramod K.; Jacquot, Pierre; Pflug, Leopold

    1988-02-01

    The aim of this research is to use holographic interferometry to evaluate the frost susceptibility of concrete. Concrete specimens are subjected to subzero temperatures inside a freezing cabinet. A holographic system is implanted astride both the interior and exterior of the cabinet. Problems related to the implementation of such a measurement system are discussed, and ways to overcome them are described. A fringe control capability eliminates the influence of rigid-body movements and controls the fringe density. The developed system enables one to monitor in real time the evolution of the deformation of concrete specimens exposed to freezing cycles. Besides demonstrating the existence of stresses arising from the thermal incompatibility between the components of the concrete, the method provides an accurate measurement of the temperature at which this thermal incompatibility leads to the impairment of the hardened concrete paste. Results computed from the application of a mathematical model are compared with those obtained by holographic interferometry. Close agreement between the numerically computed and the experimentally observed behavior is obtained.

  1. Structure of the Pliocene Camp dels Ninots maar-diatreme (Catalan Volcanic Zone, NE Spain)

    NASA Astrophysics Data System (ADS)

    Oms, O.; Bolós, X.; Barde-Cabusson, S.; Martí, J.; Casas, A.; Lovera, R.; Himi, M.; Gómez de Soler, B.; Campeny Vall-Llosera, G.; Pedrazzi, D.; Agustí, J.

    2015-11-01

    Maar volcanoes expose shallower or deeper levels of their internal structure as a function of the degree of erosion. In El Camp dels Ninots maar-diatreme (Catalan Volcanic Zone, Spain), the tephra ring has been largely eroded, and the remaining volcanic deposits infilling the diatreme are hidden under a lacustrine sedimentary infill of the crater. The volcano shows hardly any exposure, so its study needs the application of direct (e.g., boreholes) and indirect (shallow geophysics) subsurface exploration techniques. Additionally, this maar-diatreme was built astride two different substrates (i.e., mixed setting) as a result of its location in a normal fault separating Neogene sediments from Paleozoic granites. In order to characterize the internal structure and post-eruption stratigraphy of the maar-diatreme, we did geological studies (mapping, continuous core logging, and description of the tephra ring outcrops) and near-surface geophysics, including nine transects of electric resistivity tomography and a gravity survey. Results show that the deeper part of the diatreme is excavated into granites and is relatively steep and symmetrical. The uppermost diatreme is asymmetrical because of mechanical contrast between granites and Pliocene sands. The maar crater contained a lake permanently isolated from the surrounding relief and was deep enough to host anoxic bottom waters while its margins had shallower waters. These lake conditions preserved the remarkable Pliocene fossil record found in the lacustrine sediments.

  2. Screening-Constant-by-Unit-Nuclear-Charge method investigations of high lying ({sup 1}D{sub 2},{sup 1}S{sub 0}) ns, nd Rydberg series in the photoionization spectra of the halogen-like ion Kr{sup +}

    SciTech Connect

    Sakho, I.

    2014-01-15

    Energy positions and quantum defects of the 4s{sup 2}4p{sup 4} ({sup 1}D{sub 2},{sup 1}S{sub 0}) ns, nd Rydberg series originating from the 4s{sup 2}4p{sup 52}P{sub 3/2}{sup ∘} ground state and from the 4s{sup 2}4p{sup 52}P{sub 1/2}{sup ∘} metastable state of Kr{sup +} are reported. Calculations are performed using the Screening Constant by Unit Nuclear Charge (SCUNC) method. The results obtained are in suitable agreement with recent experimental data from the combined ASTRID merged-beam set up and Fourier Transform Ion Cyclotron Resonance device (Bizau et al., 2011), ALS measurements (Hinojosa et al., 2012), and multi-channel R-matrix eigenphase derivative calculations (McLaughlin and Balance, 2012). In addition, analysis of the 4s{sup 2}4p{sup 4}({sup 1}D{sub 2})nd and the 4s{sup 2}4p{sup 4}({sup 1}S{sub 0})nd resonances is given via the SCUNC procedure. The excellent results obtained from our work point out that the SCUNC formalism may be used to confirm the results of the analysis from the standard quantum-defect expansion formulas. Eventual errors occurring in the analysis can then be automatically detected and corrected via the SCUNC procedure.

  3. Anomalous folds associated with the east-central part of the Garlock Fault, southeast California

    USGS Publications Warehouse

    Smith, G.I.

    1991-01-01

    The east-central part of the left-lateral Garlock Fault, in southeast California, is associated with three broad folds that trend and plunge northeast. The folds, which lie north, south, and astride the fault, postdate deposition of alluvial gravels that at one time formed a continuous northwest-sloping fan. Corrected tilting rates vary from about 2.5?? to 4.7??/m.y.; the total shortening of about 7.5 m developed at a minimum rate of 12.5 m/m.y. The orientations of these folds imply northwest-southeast compression, which is anomalous when viewed in the context of regional tectonics. These anomalous features are interpreted as evidence that episodes of NW-SE compression along the Garlock Fault do occur, and although oriented about 90?? from the average of conventional - and presently observed - compression directions, they have occurred during much (most?) of the Cenozoic Era, including the past 0.6 m.y. -from Author

  4. Contributions of cretaceus quiet zone natural remanent magnetization to Magsat anomalies in the Southwest Indian Ocean

    NASA Technical Reports Server (NTRS)

    Fullerton, Lawrence G.; Frey, Herbert V.; Roark, James H.; Thomas, Herman H.

    1994-01-01

    The Magsat magnetic anomalies over the Southwest Indian Ocean are modeled using a combination of induced plus viscous remanent magnetization (IM/VRM) and natural remanent magnetization (NRM). Two broad, roughly parallel, SW to NE trending triple-peaked positive anomalies dominate the region, one lying south of Africa and the other north of Antarctica. Although these anomaly peaks generally correspond with the Agulhas Plateau/Maud Rise, Mozambique Plateau/Astrid Ridge, and Madagascar Ridge/Conrad Rise conjugate pairs, the IM/VRM contribution from structural characteristics (i.e., crustal thickness) accounts for only about 20% of the anomaly amplitudes. A spatially variable but observationally constrained NRM contribution in Cretaceous Quiet Zone (KQZ) crust is required to account for the location, shape, and amplitude contrast of these anomalies. Many crustal features in the Southwest Indian Ocean near Antarctica have little geophysical data to constrain their structure but do hagve tectonic conjugates near Africa for which much more geophysical data are generally available. Using geophysical and geological constraints from one member to model the magnetization structure of its conjugate reproduces the observed Magsat reduced-to-pole anomalies over both structures very well. This suggests that no significant alteration in their magnetization structure has occurred since the features split. Models of these conjugate structures show that IM/VRM reproduces the Magsat anomalies associated with non-KQZ crust but that both IM/VRM and a dominant NRM component are required to explain the anomalies associated with KQZ crust.

  5. Antarctic slush-ice algal accumulation not quantified through conventional satellite imagery: Beware the ice of March

    NASA Astrophysics Data System (ADS)

    Lieser, J. L.; Curran, M. A. J.; Bowie, A. R.; Davidson, A. T.; Doust, S. J.; Fraser, A. D.; Galton-Fenzi, B. K.; Massom, R. A.; Meiners, K. M.; Melbourne-Thomas, J.; Reid, P. A.; Strutton, P. G.; Vance, T. R.; Vancoppenolle, M.; Westwood, K. J.; Wright, S. W.

    2015-11-01

    Our current knowledge of broad-scale patterns of primary production in the Southern Ocean is derived from satellite ocean-colour estimates of chlorophyll a (Chl a) in the open ocean, typically in spring-summer. Here, we provide evidence that large-scale intra-ice phytoplankton surface aggregation occur off the coast of Antarctica during austral autumn, and that these "blooms" are largely undetected in satellite ocean-colour time series (which mask the ice-covered ocean). We present an analysis of (i) true-colour (visible) satellite imagery in combination with (ii) conventional ocean-colour data, and (iii) direct sampling from a research vessel, to identify and characterise a large-scale intra-ice algal occurrence off the coast of East Antarctica in early autumn (March) 2012. We also present evidence of these autumn "blooms" in other regions (for example, Princess Astrid Coast in 2012) and other years (for example, Terra Nova Bay in 2015) implying regular and widespread occurrence of these phenomena. The occurrence of such undetected algal accumulations implies that the magnitude of primary production in the Southern Ocean is currently underestimated.

  6. A Mars Pathfinder landing on a recently drained ephemeral sea: Cerberus Plains, 6 deg N, 188 deg W

    NASA Technical Reports Server (NTRS)

    Brakenridge, G. Robert

    1994-01-01

    Along a 500 km-wide belt extending between 202 deg and 180 deg W and lying astride the martian equator, moderately low-albedo, uncratered smooth plains exhibit low thermal inertia and potentially favorable conditions for the preservation of near-surface ice. The Cerberus Plains occupy a topographic trough as much as 2 km below the planetary datum, and the denser atmosphere at these altitudes would also favor long residence times for near-surface ice once emplaced. The plains have previously been interpreted as the result of young (late Amazonian) low viscosity lava flows or similarly youthful fluvial deposition. However, the plains are also included in maps of possibly extensive martian paleoseas or paleolakes. Ice emplaced as such seas dissipated could still be preserved under thin (a few tens of centimeters) sedimentary cover. In any case, and if a sea once existed, aqueous-born interstitial cementation, probably including hydrated iron oxides and sulfate minerals, would have been favored and is now susceptible to investigation by the Pathfinder alpha proton x-ray spectrometer and multispectral imager.

  7. Surface mount component jig

    DOEpatents

    Kronberg, James W.

    1990-08-07

    A device for bending and trimming the pins of a dual-inline-package component and the like for surface mounting rather than through mounting to a circuit board comprises, in a first part, in pin cutter astride a holder having a recess for holding the component, a first spring therebetween, and, in a second part, two flat members pivotally interconnected by a hinge and urged to an upward peaked position from a downward peaked position by a second spring. As a downward force is applied to the pin cutter it urges the holder downward, assisted by the first spring and a pair of ridges riding on shoulders of the holder, to carry the component against the upward peaked flat members which guide the pins outwardly. As the holder continues downwardly, the flat members pivot to the downward peaked position bending the pins upwardly against the sides of the holder. When the downward movement is met with sufficient resistance, the ridges of the pin cutter ride over the holder's shoulders to continue downward to cut any excess length of pin.

  8. Synthesis and electronic structure of single-layer TaS2

    NASA Astrophysics Data System (ADS)

    Sanders, Charlotte; Sohanfo Ngankeu, Arlette; Dendzik, Maciej; Bianchi, Marco; Hofmann, Philip

    Bulk TaS2 is an intriguing material that exhibits charge density wave phases, Mott physics, and superconductivity; however, little work has been done on single-layer (SL) TaS2. Progress in this area demands a method for controllably fabricating high-quality, uniform samples with low defect densities. We have succeeded in epitaxially growing SL TaS2, using the Au(111) substrate. The monolayer exhibits a well-defined orientation with respect to the substrate, a strong preference toward forming triangular islands, and a moire superstructure. Furthermore, long deposition times lead to smooth layer-by-layer growth of TaS2. In this talk, I will present band structure measurements acquired by angle-resolved photoemission spectroscopy (ARPES) on TaS2/Au samples fabricated in situ at the SGM3 end station of the ASTRID2 synchrotron facility in Denmark. Scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) elucidate the material's structural properties and interaction with the substrate.

  9. No evidence for Evans' holes in the A, B, C vibrational structure of potassium dihydrogen arsenate

    NASA Astrophysics Data System (ADS)

    Tomkinson, John; Parker, Stewart F.; Lennon, David

    2010-07-01

    We have used inelastic neutron scattering (INS) spectroscopy to study the "A, B, C" region of the hydrogen bond in potassium dihydrogen arsenate. The broad spectral feature observed in infrared spectroscopy is shown to be associated with a ridge of constant intensity in the INS, which follows the recoil line for a unit-mass particle. The onset energy of the ridge is unclear but, we believe, is associated with the optical "C" feature at 1610 cm-1, and which we assign to ν(O-H). The "B" and "A" optical bands were both demonstrated to be two-quantum events and are, thus, not associated with the fundamental ν(O-H). They are readily assigned to the harmonic overtone δ(OH)(0-2) and the combination γ(OH)(0-1)+δ(OH)(0-1), which both sit astride the ridge and there is no evidence for Evans' holes. The other overtone, γ(OH)(0-2), has been assigned to a very weak feature, observed for the first time at 1900 cm-1. A simple model was used to describe the intensity distributions.

  10. Resource investigation of low- and moderate-temperature geothermal areas in San Bernardino, California. Part of the third year report, 1980-81, of the US Department of Energy-California State-Coupled Program for Reservoir Assessment and Confirmation

    SciTech Connect

    Youngs, L.G.; Bezore, S.P.; Chapman, R.H.; Chase, G.W.

    1981-08-01

    Ninety-seven geothermal wells and springs were identified and plotted on a compiled geologic map of the 40-square-mile study area. These wells and springs were concentrated in three distinguishable resource areas: Arrowhead Hot Springs; South San Bernardino; and Harlem Hot Springs - in each of which detailed geophysical, geochemical, and geological surveys were conducted. The Arrowhead Hot Springs geothermal area lies just north of the City of San Bernardino in the San Bernardino Mountains astride a shear zone (offshoot of the San Andreas fault) in pre-Cambrian gneiss and schist. The Harlem Hot Springs geothermal area, on the east side of the City, and the south San Bernardino geothermal area, on the south side, have geothermal reservoirs in Quaternary alluvial material which overlies a moderately deep sedimentary basin bound on the southwest by the San Jacinto fault (a ground water barrier). Geothermometry calculations suggest that the Arrowhead Hot Springs geothermal area, with a maximum reservoir temperature of 142/sup 0/C, may have the highest maximum reservoir temperature of the three geothermal areas. The maximum temperature recorded by CDMG in the south San Bernardino geothermal area was 56/sup 0/C from an artesian well, while the maximum temperature recorded in the Harlem Hot Springs geothermal area was 49.5/sup 0/C at 174 meters (570 feet) in an abandoned water well. The geophysical and geological surveys delineated fault traces in association with all three of the designated geothermal areas.

  11. Spatial cross-correlation of Antarctic Sea ice and seabed topography

    NASA Technical Reports Server (NTRS)

    Deveaux, Richard D.; Phelan, Michael J.

    1990-01-01

    A time series of derived sea ice concentrations as observed about Antarctica by the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) satellite in 1983 is considered. The degree of spatial cross correlation between these data and seabed topography is quantified. The approach is to implement a statistical image processing filter designed to extract local patterns of spatial cross correlation over the entire sea ice field as it undergoes daily changes. Throughout the sea ice, it was found that large scale variations in sea ice concentration correlate systematically with variations in the topography of the seabed. Generally speaking, high concentrations of sea ice occur over deep ocean, whereas areas of encavement, early dissipation and polynya formation develop over topographic features of high elevation. The latter was studied in detail with respect to the features Maud Rise, Astrid Ridge and the continental shelf in the Cosmonaut and Ross Seas. In each case, it is shown that an encavement in sea ice, a polynya, or both develops in the vicinity of the feature in question. As these results are quantified in terms of spatial cross correlation, a potential role is inferred for seabed topography in such fluctuations in the sea ice about Antarctica.

  12. Dissociative recombination of the cation and dication of CO{sub 2}

    SciTech Connect

    Seiersen, K.; Al-Khalili, A.; Heber, O.; Jensen, M. J.; Nielsen, I. B.; Pedersen, H. B.; Safvan, C. P.; Andersen, L. H.

    2003-08-01

    Dissociative recombination of CO{sub 2} ions has been studied at the heavy-ion storage ring ASTRID. Electrons were scattered on both singly and doubly charged positive ions of the molecule, and the absolute cross sections were measured in the energy range of 10{sup -3}-10{sup 1} eV. Thermal rate coefficients of {alpha}(CO{sub 2}{sup +}) =(6.5{+-}1.9)x10{sup -7}x(300/T[K]){sup 0.8} cm{sup 3} s{sup -1} and {alpha}(CO{sub 2}{sup 2+}) =(6.2{+-}2.1)x10{sup -7}x(300/T[K]){sup 0.5} cm{sup 3} s{sup -1} were extracted. Furthermore, branching ratios for molecular breakup into neutral product channels have been measured using a grid technique. The branching ratios were measured at {approx}0 eV for CO{sub 2}{sup +}, and in the entire energy range from 10{sup -3} eV to 50 eV for CO{sub 2}{sup 2+}. This measurement reveals pronounced structure in the CO{sub 2}{sup 2+} branching ratios.

  13. Scientific overview: CSCI-CITAC Annual General Meeting and Young Investigators' Forum 2014.

    PubMed

    Keow, Jonathan; Zhao, Eric; Samuel, Nardin; Dey, Ayan; Schneider, Raphael; Chen, Michael; Wang, Xin

    2015-01-01

    The Canadian Society of Clinician Investigators (CSCI) and Clinical Investigator Trainee Association of Canada/Association des cliniciens-chercheurs en formation du Canada (CITAC/ACCFC) annual general meeting (AGM) was held in Toronto during November 21-24, 2015 for the first time in conjunction with the University of Toronto Clinician-Investigator Program Research Day. The overall theme for this year's meeting was the role of mentorship in career development, with presentations from Dr. Chaim Bell (University of Toronto), Dr. Shurjeel Choudhri (Bayer Healthcare), Dr. Ken Croitoru (University of Toronto), Dr. Astrid Guttman (University of Toronto), Dr. Prabhat Jha (University of Toronto) and Dr. Sheila Singh (McMaster University). The keynote speakers of the 2014 AGM included Dr. Qutayba Hamid, who was presented with the Distinguished Scientist Award, Dr. Ravi Retnakaran, who was presented with the Joe Doupe Award, and Dr. Lorne Babiuk, who was the CSCI-RCPSC Henry Friesen Award winner. The highlight of the conference was, once again, the outstanding scientific presentations from the numerous clinician investigator (CI) trainees from across the country who presented at the Young Investigators' Forum. Their research topics spanned the diverse fields of science and medicine, ranging from basic science to cutting-edge translational research, and their work has been summarized in this review. Over 120 abstracts were presented at this year's meeting. This work was presented during two poster sessions, with the six most outstanding submitted abstracts presented in the form of oral presentations during the President's Forum. PMID:26278424

  14. 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)

  15. Laser-cooled bunched ion beam

    SciTech Connect

    Schiffer, J.P.; Hangst, J.S.; Nielsen, J.S.

    1995-08-01

    In collaboration with the Arhus group, the laser cooling of a beam bunched by an rf electrode was investigated at the ASTRID storage ring. A single laser is used for unidirectional cooling, since the longitudinal velocity of the beam will undergo {open_quotes}synchrotron oscillations{close_quotes} and the ions are trapped in velocity space. As the cooling proceeds the velocity spread of the beam, as well as the bunch length is measured. The bunch length decreases to the point where it is limited only by the Coulomb repulsion between ions. The measured length is slightly (20-30%) smaller than the calculated limit for a cold beam. This may be the accuracy of the measurement, or may indicate that the beam still has a large transverse temperature so that the longitudinal repulsion is less than would be expected from an absolutely cold beam. Simulations suggest that the coupling between transverse and longitudinal degrees of freedom is strong -- but this issue will have to be resolved by further measurements.

  16. Exploring Differences in Inpatient Drug Purchasing Cost Between Two Pediatric Hospitals

    PubMed Central

    Nydert, Per; Poole, Robert

    2012-01-01

    OBJECTIVES In this study, the hospital cost of purchasing drugs at two children's hospitals is explored with respect to high-cost drugs and drug classes and discussed with regard to differences in hospital setting, drug price, or number of treatments. METHODS The purchasing costs of drugs at the two hospitals were retrieved and analyzed. All information was connected to the Anatomic Therapeutic Chemical code and compared in a Microsoft Access database. RESULTS The 6-month drug purchasing costs at Astrid Lindgren Children's Hospital (ALCH), Stockholm, Sweden, and Lucile Packard Children's Hospital at Stanford (LPCH), Palo Alto, California, are similar and result in a cost per patient day of US $149 and US $136, respectively. The hospital setting and choice of drug products are factors that influence the drug cost in product-specific ways. CONCLUSIONS Several problems are highlighted when only drug costs are compared between hospitals. For example, the comparison does not take into account the amount of waste, risk of adverse drug events, local dosing strategies, disease prevalence, and national drug-pricing models. The difference in cost per inpatient day at ALCH may indicate that cost could be redistributed in Sweden to support pediatric pharmacy services. Also, when introducing new therapies seen at the comparison hospital, it may be possible to extrapolate the estimated increase in cost. PMID:23413208

  17. Analogous intruder behavior near Ni, Sn, and Pb isotopes

    NASA Astrophysics Data System (ADS)

    Liddick, S. N.; Walters, W. B.; Chiara, C. J.; Janssens, R. V. F.; Abromeit, B.; Ayres, A.; Bey, A.; Bingham, C. R.; Carpenter, M. P.; Cartegni, L.; Chen, J.; Crawford, H. L.; Darby, I. G.; Grzywacz, R.; Harker, J.; Hoffman, C. R.; Ilyushkin, S.; Kondev, F. G.; Larson, N.; Madurga, M.; Miller, D.; Padgett, S.; Paulauskas, S. V.; Rajabali, M. M.; Rykaczewski, K.; Seweryniak, D.; Suchyta, S.; Zhu, S.

    2015-08-01

    Near shell closures, the presence of unexpected states at low energies provides a critical test of our understanding of the atomic nucleus. New measurements for the N =42 isotones Co6927 and Cu7129, along with recent data and calculations in the Ni isotopes, establish a full set of complementary, deformed, intruder states astride the closed-shell 28Ni isotopes. Nuclei with a one-proton hole or one-proton particle adjacent to Z =28 were populated in β -decay experiments and in multinucleon transfer reactions. A β -decaying isomer, with a 750(250)-ms half-life, has been identified in 42,27,69Co. It likely has low spin and accompanies the previously established 7 /2- state. Complementary data for the levels of isotonic 42,29,71Cu support the presence of a deformed, Δ J =1 band built on the proton intruder 7 /2- level at 981 keV. These data, together with recent studies of lower-mass Co and Cu isotopes and extensive work near 68Ni, support the view that intruder states based on particle-hole excitations accompany all closed proton shells with Z ≥28 .

  18. High resolution dating of moraines on Kodiak Island, Alaska links Atlantic and North Pacific climatic changes during the late glacial

    SciTech Connect

    Mann, D.H. . Alaska Quaternary Center)

    1992-01-01

    Much less is known about the paleoclimate and paleoceanography of the North Pacific than the North Atlantic despite the North Pacific's important role in the global ocean-climate system. Kodiak Island lies in the northwestern Gulf of Alaska astride the eastern end of the Aleutian Low. On southwestern Kodiak Island, coastal bluffs section a series of moraines, kettle ponds, and bogs formed between 15 and 9 ka BP. Distinctive tephras from volcanoes on the Alaska Peninsula provide time-lines within the stratigraphy. Deformation events recorded in sediment stacks from basins within glaciotectonic landforms allows precise dating of glacial events. An ice cap occupied the Kodiak archipelago during the last glaciation. Three glacial advances of the southwestern margin of this ice cap occurred after 15 ka BP. At 13.4 ka, piedmont ice lobes formed large push moraines extending into Shelikof Strait during the Low Cape Advance. The less-extensive Tundra Advance culminated between 12 and 11.7 ka BP followed by glacier retreat then readvance to form the prominent Olga Moraine system between 11 and 10 ka BP. The timing of the Tundra and Olga Advances correlates closely with that of the Older and Younger Dryas cold episodes in northwestern Europe suggesting that these climatic oscillations were synchronous throughout the northern hemisphere.

  19. Yarkovsky/YORP chronology of asteroid families

    NASA Astrophysics Data System (ADS)

    Vokrouhlický, D.; Brož, M.; Bottke, W. F.; Nesvorný, D.; Morbidelli, A.

    2006-05-01

    Asteroid families are the byproducts of catastrophic collisions whose fragments form clusters in proper semimajor axis, eccentricity, and inclination space. Although many families have been observed in the main asteroid belt, only two very young families, Karin and Veritas, have well-determined ages. The ages of other families are needed, however, if we hope to infer information about their ejection velocity fields, space weathering processes, etc. In this paper, we developed a method that allows us to estimate the ages of moderately young asteroid families (approximately in between 0.1 and 1 Gyr). We apply it to four suitable cases—Erigone, Massalia, Merxia, and Astrid—and derive their likely ages and approximate ejection velocity fields. We find that Erigone and Merxia were produced by large catastrophic disruption events (i.e., parent body ⩾100 km) that occurred approximately 280 and 330 Myr ago, respectively. The Massalia family was likely produced by a cratering event on Asteroid (20) Massalia less than 200 Myr ago. Finally, the Astrid family, which was produced by the disruption of a 60-70 km asteroid, is 100-200 Myr old, though there is considerable uncertainty in this result. We estimate that the initial ejection velocities for these families were only a few tens of meters per second, consistent with numerical hydrocode models of asteroid impacts. Our results help to verify that asteroid families are constantly undergoing dynamical orbital evolution from thermal (Yarkovsky) forces and spin vector evolution from thermal (YORP) torques.

  20. Feeder layer- and animal product-free culture of neonatal foreskin keratinocytes: improved performance, usability, quality and safety.

    PubMed

    De Corte, Peter; Verween, Gunther; Verbeken, Gilbert; Rose, Thomas; Jennes, Serge; De Coninck, Arlette; Roseeuw, Diane; Vanderkelen, Alain; Kets, Eric; Haddow, David; Pirnay, Jean-Paul

    2012-03-01

    Since 1987, keratinocytes have been cultured at the Queen Astrid Military Hospital. These keratinocytes have been used routinely as auto and allografts on more than 1,000 patients, primarily to accelerate the healing of burns and chronic wounds. Initially the method of Rheinwald and Green was used to prepare cultured epithelial autografts, starting from skin samples from burn patients and using animal-derived feeder layers and media containing animal-derived products. More recently we systematically optimised our production system to accommodate scientific advances and legal changes. An important step was the removal of the mouse fibroblast feeder layer from the cell culture system. Thereafter we introduced neonatal foreskin keratinocytes (NFK) as source of cultured epithelial allografts, which significantly increased the consistency and the reliability of our cell production. NFK master and working cell banks were established, which were extensively screened and characterised. An ISO 9001 certified Quality Management System (QMS) governs all aspects of testing, validation and traceability. Finally, as far as possible, animal components were systematically removed from the cell culture environment. Today, quality controlled allograft production batches are routine and, due to efficient cryopreservation, stocks are created for off-the-shelf use. These optimisations have significantly increased the performance, usability, quality and safety of our allografts. This paper describes, in detail, our current cryopreserved allograft production process. PMID:21394485

  1. Glycerol treatment as recovery procedure for cryopreserved human skin allografts positive for bacteria and fungi.

    PubMed

    Verbeken, Gilbert; Verween, Gunther; De Vos, Daniel; Pascual, Bruno; De Corte, Peter; Richters, Cornelia; De Coninck, Arlette; Roseeuw, Diane; Ectors, Nadine; Rose, Thomas; Jennes, Serge; Pirnay, Jean-Paul

    2012-03-01

    Human donor skin allografts are suitable and much used temporary biological (burn) wound dressings. They prepare the excised wound bed for final autografting and form an excellent substrate for revascularisation and for the formation of granulation tissue. Two preservation methods, glycerol preservation and cryopreservation, are commonly used by tissue banks for the long-term storage of skin grafts. The burn surgeons of the Queen Astrid Military Hospital preferentially use partly viable cryopreserved skin allografts. After mandatory 14-day bacterial and mycological culture, however, approximately 15% of the cryopreserved skin allografts cannot be released from quarantine because of positive culture. To maximize the use of our scarce and precious donor skin, we developed a glycerolisation-based recovery method for these culture positive cryopreserved allografts. The inactivation and preservation method, described in this paper, allowed for an efficient inactivation of the colonising bacteria and fungi, with the exception of spore-formers, and did not influence the structural and functional aspects of the skin allografts. PMID:21360142

  2. Disgusting bodies, disgusting religion: the biology of Tantra.

    PubMed

    Ellis, Thomas B

    2011-01-01

    Hard-core Tantric practice is disgusting, a point several scholars make. Scholarly interpretations of Tantric disgustingness, however, tend to follow the lead of Mary Douglas in suggesting that what disgusts is ultimately a reflection of social–historical concerns with borders and boundaries. Such interpretations fail to take seriously the Tantric consumption of feces, menstrual blood, urine, semen, and phlegm. Likewise, they fail to take seriously the particular sexual act involved, that is, intercourse with a menstruating, riding-astride, out-of-caste, mother-substitute. Consulting contemporary disgust research, I suggest that hard-core Tantra is literally disgusting because it is literally maladaptive. Disgust was naturally selected to deter the ingestion of bio-toxic pathogens as well as the practice of suboptimal sexual intercourse. Disgust maintains the species' viability. Tantra confounds disgust and thus disgusts. Tantra engages antibiological behaviors in its characteristically religious war against the body. As a disgusting religion, Tantra may be a perfected religion. PMID:22180926

  3. Helium transport in sediment pore fluids of the Congo-Angola margin

    NASA Astrophysics Data System (ADS)

    Chaduteau, Carine; Jean-Baptiste, Philippe; Fourré, Elise; Charlou, Jean-Luc; Donval, Jean-Pierre

    2009-01-01

    During the ZaïRov2 cruise of the ZaïAngo project (1998-2000) on the passive Congo-Angola margin, several gravity cores were analyzed for helium isotopic composition of sedimentary pore waters in two cold fluid seepage zones: the Astrid slide area and the Regab giant pockmark. Gas concentration and isotopic composition are presented along with thermal data in terms of the origin and circulation of fluids. Helium isotope data lie on a mixing line between bottom seawater and an almost pure radiogenic. Helium and temperature vertical profiles are well described by the classic diffusion-advection equation. On the basis of He profiles, we estimate the advection rate on the rim of the pockmark between 1.2 and 2.3 mm/a. The He flux derived for a pure diffusive regime (2.4 × 10-8 mol/m2/a) can favorably be compared to literature data and contrasts with the flux computed close to the pockmark center (1.9 × 10-7 mol/m2/a). Helium depth profiles turned to be more sensitive to advection rate than temperature profiles are.

  4. [Transylvanian refugees and the plague in 1708-1709].

    PubMed

    Kis, D

    1993-01-01

    Owing to the overwhelming military power of the Habsburg forces Transylvanian sympathizers fled twice to Hungary during the Rákóczi uprising (1704-1711): first in 1704-1706 and then in 1707-1711. In the autumn of 1707 they numbered as much as ten thousand people, and according to the decrees of the diet at Kisvárda, they were settled down in smaller units in around Szabolcs, Szatmár, Bereg, Ung, Ugocsa and Máramaros counties. Though always short of money, the leaders of the ukprising created a system that satisfied the basic needs of these refugees. By the end of the rebellion, nevertheless, as the territory controlled by Rákóczi's armies decreased considerably, the refugees were forced to move on and on, which certainly led to a corruption of their food supplies, accommodation and hygienic conditions. The worst among all came with the plague. The author examines the effects of the epidemic and the counter-measures taken by the individual and the authorities of the uprising. Kis has consulted the main Hungarian books of that age that referred to black death (among others Anna Zay's Herbarium [1719], Samuel Köleséri's Pestis Daicae, György Komáromi Csipkés's Pestis pestise, Ferenc Pápai Páriz's Pax Corporis and A [estos betegség etc., and Máté Tsanaki's A Döghalálról, etc.), as well as many archival papers (the correspondence of Count Sándor Károlyi with his wife Krisztina Barkóczy, thos of General Bercsényi to his wife and Prince Rákóczi, and some doctors' reports, etc.). His main source, however, is Zsigmond Szaniszló's diary. Szaniszló was a former fobiró (chief-sheriff) of the Transsylvanian Torda city, an Anti-Trinitarian stronghold, and remained a leader of his people during the emigration. According to his notes, which the author has compared with the data given by the others, there were hardly any measures taken against plague in this community. Although Szaniszló gives detailed descriptions about the everyday life of the

  5. Hydrogeology of the Fort Peck Indian Reservation, northeastern Montana

    SciTech Connect

    Thamke, J.N.; Craigg, S.D. )

    1993-04-01

    The Fort Peck Indian Reservation, which encompasses about 3,300 square miles in northeastern Montana, is characterized by three major types of terrain: Missouri River bottom lands, badlands, and topographically higher benchlands. The reservation lies on the western flank of the Williston Basin, a large, petroleum-rich structural depression in Montana, North and South Dakota, and Saskatchewan and Manitoba, Canada. Structurally, the area is not complex, although the Poplar Anticline trends northwest through the central part of the reservation. The East Poplar Oil Field lies astride this structure and produces from the mississippian Madison Group. Geologic units that crop out in the reservation are the Upper Cretaceous Bearpaw Shale, Fox Hills Sandstone, and Hell Creek Formation; the Tertiary Fort Union and Flaxville Formations; and Quaternary glacial and alluvial deposits. Most ground water is produced from alluvial deposits, glacial deposits, Flaxville Formation, Fort Union Formation, Hell Creek Formation, and Fox Hills Sandstone. Well depths range from about 15 to 300 feet below land surface; depth to water ranges from about 5 to 160 feet. Units deeper than the Fox Hills Sandstone are not important aquifers because of the underlying, thick Bearpaw Shale, and because the water is too mineralized for most uses. Background dissolved-solids concentrations of water from major aquifers is in the range of about 300 to 3,000 milligrams per liter. However, in the East Poplar Oil Field, water in the alluvial and glacial deposits has been contaminated near brine-disposal facilities; dissolved-solids concentration of water is as much as 114,000 milligrams per liter.

  6. Preliminary assessment of the geologic setting, hydrology, and geochemistry of the Hueco Tanks geothermal area, Texas and New Mexico. Geological Circular 81-1

    SciTech Connect

    Henry, C.D.; Gluck, J.K.

    1981-01-01

    The Hueco Tanks geothermal area contains five known but now inactive hot wells (50/sup 0/ to 71/sup 0/C). The area trends north-south along the east side of Tularosa-Hueco Bolson astride the Texas-New Mexico border approximately 40 km northeast of El Paso. Because of its proximity to El Paso, geothermal water in the Hueco Tanks area could be a significant resource. Hueco Bolson is an asymmetric graben. Greatest displacement along boundary faults is on the west side adjacent to the Franklin Mountains. Faults, probably with less displacement, also form an irregular boundary on the east side of the bolson. Several probable faults may allow the rise of thermal waters from depth. Ground water in the central part of Hueco Bolson flows southward to the Rio Grande. However, four of the five hot wells occur in a ground-water trough along the eastern margin of the bolson. The trough may be bounded by one of the postulated faults serving as a barrier to ground-water flow. Data on permeability of potential reservoir rocks, including basin fill and fractured bedrock, suggest that they may be sufficiently permeable for development of geothermal water. The concentration of dissolved solids in the geothermal waters varies from 1100 to at least 12,500 mg/L, but most waters show high concentrations. They are Na-Cl-(SO/sub 4/) waters similar in composition to nonthermal waters in basin fill. The composition probably results from contact with evaporite deposits either in basin fill or in Paleozoic bedrock. Shallow reservoirs reach maximum temperatures of about 80/sup 0/ to 110/sup 0/C. Available data are too limited to evaluate adequately the resource potential of geothermal water in the Hueco Tanks area.

  7. Walking the tightrope: trends in African freshwater systematic ichthyology.

    PubMed

    Skelton, P H; Swartz, E R

    2011-12-01

    Africa is blessed with an abundance and rich diversity of freshwater fishes, reflecting its Gondwanan history and geographical position astride the equator. Africa is, however, relatively poorly serviced scientifically, in this respect presenting a challenge to the tension between conserving biodiversity and sustainable development. Biosystematics has experienced several paradigm shifts in the past half century, including the rise of cladistics and more recently the adoption of molecular DNA applications to taxonomy and phylogeny and the assembly and manipulation of large data sets in an era of major development of bioinformatics. The richness of African biodiversity is a magnet to the global systematic community that, to a degree, offsets the disadvantage of an impoverished indigenous scientific capacity. Conservation biology, however, is rooted more closely to the local situation and therefore requires indigenous taxonomic services that are inevitably scarce. Balancing this network of tensions between scientific knowledge generation and application is like walking a tightrope for existing African scientific resources, and to cope it is essential to embrace modern innovative approaches such as barcoding to identify organisms. This paper considers the historical development of African freshwater ichthyology, presents a suite of recent examples illustrating trends in systematic ichthyology in Africa and draws conclusions to suggest that both traditional and new-age approaches to taxonomy are necessary for a complete understanding and appreciation of African freshwater fish diversity and its conservation. The chosen examples also suggest that the tensions between the approaches can be effectively managed provided exponents work collaboratively. The emerging evidence indicates that the combined skills and insight of complex scientific teams including systematists, ecologists, molecular biologists and earth scientists are needed to resolve the deep complexity of

  8. Dolomitization and dedolomitization models in a fractured reservoir, Reed City oil field, Michigan

    SciTech Connect

    Carlton, R.R.; Prouty, C.E.

    1983-03-01

    Hydrocarbon production in the Michigan basin is essentially from pinnacle reefs or fractured reservoirs. The epigenetically formed porous dolomite reservoir rock is intimately related to the shear faults (channelways for rising high Mg/Ca ratio fluids) and to the resulting shear folds, the latter showing dolomite/calcite ratios increasing generally from outer closure to the fold axes. The Reed City field (anticline) of western Michigan represents a dramatic exception to this picture with the dolomite/calcite ratio increasing from outer closure to maximum part way up the limbs then decreasing to the axis. This lowest zone is the only unit not dedolomitized, a fact perhaps commensurate with its low stratigraphic position at the bottom of (and apparently beyond the reach of) the descending high-calcium, low-magnesium waters what brought about the dedolomitization. The dedolomitization model would call for a shallow water to exposed oxidizing environment, possible with the position of this area astride the West Michigan Barrier that separates a lagoonal facies from a more open sea facies to the east. Thus, waters with a high Ca/Mg ratio passed down the same shear faults that earlier were channelways for the rising high Mg/Ca ratio waters. On the bases of isopach, structure and dolomite/calcite (Isodol) maps, one can piece together a reasonably chronological sequence of pre-Dundee shear faulting and folding, post-Traverse upward migration of dolomitizing fluids, upward migration of hydrocarbons along the shear faults, downward-moving dedolomitizing fluids, and a later episode of faulting (especially shear cross-faults).

  9. Geologic Map of the Tower Peak Quadrangle, Central Sierra Nevada, California

    USGS Publications Warehouse

    Wahrhaftig, Clyde

    2000-01-01

    Introduction The Tower Peak quadrangle, which includes northernmost Yosemite National Park, is located astride the glaciated crest of the central Sierra Nevada and covers an exceptionally well-exposed part of the Sierra Nevada batholith. Granitic plutonic rocks of the batholith dominate the geology of the Tower Peak quadrangle, and at least 18 separate pre-Tertiary intrusive events have been identified. Pre-Cretaceous metamorphic rocks crop out in the quadrangle in isolated roof pendants and septa. Tertiary volcanic rocks cover granitic rocks in the northern part of the quadrangle, but are not considered in this brief summary. Potassium-argon (K-Ar) age determinations for plutonic rocks in the quadrangle range from 83 to 96 million years (Ma), including one of 86 Ma for the granodiorite of Lake Harriet (Robinson and Kistler, 1986). However, a rubidium-strontium whole-rock isochron age of 129 Ma has been obtained for the Lake Harriet pluton (Robinson and Kistler, 1986), which field evidence indicates is the oldest plutonic body within the quadrangle. This suggests that some of the K-Ar ages record an episode of resetting during later thermal events and are too young. The evidence indicates that all the plutonic rocks are of Cretaceous age, with the youngest being the Cathedral Peak Granodiorite at about 83 Ma. The pre-Tertiary rocks of the Tower Peak quadrangle fall into two groups: (1) an L-shaped area of older plutonic and metamorphic rocks, 3 to 10 km wide, that extends diagonally both northeast and southeast from near the center of the quadrangle; and (2) a younger group of large, probably composite intrusions that cover large areas in adjacent quadrangles and extend into the Tower Peak quadrangle from the east, north, and southwest.

  10. Intracardiac Echocardiography Evaluation in Secundum Atrial Septal Defect Transcatheter Closure

    SciTech Connect

    Zanchetta, Mario; Pedon, Luigi; Rigatelli, Gianluca; Carrozza, Antonio; Zennaro, Marco; Di Martino, Roberta; Onorato, Eustaquio; Maiolino, Pietro

    2003-02-15

    Purpose: This study was designed to assess the balloon sizing maneuvers and deployment of an Amplatzer Septal Occluder (ASO). In addition, intraprocedural balloon sizing was compared with off-line intracardiac echocardiographic measurements. Methods: The intracardiac echocardiography (ICE) measurements were: maximum transverse and longitudinal atrial septal defect (ASD) diameters in the aortic valve and four-chamber planes;area of the ASD and its equivalent circle diameter. Thirteen consecutive patients underwent transcatheter implantation of an ASO device using ICE guidance under local anesthesia. The device matching the balloon sizing diameter of the defect was implanted. Qualitative ICE assessment of the ASO devices implanted was performed off line. Results: The mean equivalent circle diameter predicted by ICE was 24.40 {+-} 5.61 mm and was significantly higher(p 0.027) than the ASD measured by balloonsizing (21.38 {+-} 5.28 mm). Unlike previous studies we did not find any correlation between the two measurements (correlation coefficient = 0.47). Only four of the 13 patients had optimal device positioning as shown by the qualitative ICE evaluation, whereas the remaining nine patients had inadequate device placement. This resulted in a waist diameter that was an average 26.1% undersized in seven patients and 12.7% oversized in two patients. Five of the seven patients with an undersized device had ASO-atrial septum misalignment with leftward device deviation. Conclusion: The ICE images allowed careful measurement of the dimensions of the ASD and accurately displayed the spatial relations of the ASO astride the ASD.Moreover, use of the ICE measurement led to selection of a different size of device in comparison with those of balloon sizing. The clinical benefit of this new approach needs to be rigorously tested.

  11. Hydrocarbon generation and migration routes in the east Texas basin

    SciTech Connect

    Wescott, W.; Hood, W.C. )

    1994-02-01

    The East Texas basin is a prolific, mature hydrocarbon province, producing oil and gas from several reservoirs and a variety of trap types. Many of the liquid hydrocarbons discovered in the basin are trapped in structures related to movement of the underlying Louann Salt. By determining the structural evolution of the basin, we constructed a framework to model the generation of hydrocarbons in the basin. Geochemical data indicate three major oil types: Jurassic oil, Lower Cretaceous oil, and Upper Cretaceous oil. The Jurassic source is mature throughout the basin and began to expel oil at approximately 88 Ma. The distribution of Jurassic oil in Cretaceous reservoirs shows that vertical migration routes predominated. Prospective Lower Cretaceous source rocks are only mature in the deep, central portion of the basin where expulsion began about 47 Ma. Distribution of this oil type suggests that Lower Cretaceous source rocks occur only in localized areas of the East Texas basin. Organic-rich Upper Cretaceous shales are immature in the main part of the basin, but are mature south of the Angelina-Caldwell flexure where they reached peak generation at approximately 20 Ma. Long-distance, lateral migration routes are necessary to explain the distribution of this oil type. Migration routes to the giant East Texas field may be 100 km or more. Modeling of this basin suggests an exploration approach, in mature basins, of defining migration pathways and seeking traps astride them. Traps in this position have a better probability of being filled and, all else being equal, are likely to be better fields than traps located away from the major migration routes. 42 refs., 18 figs., 2 tabs.

  12. Reconstruction of the East Africa and Antarctica continental margins

    NASA Astrophysics Data System (ADS)

    Nguyen, L. C.; Hall, S. A.; Ball, P.; Bird, D. E.

    2015-12-01

    The Early Jurassic separation of Antarctica from Africa plays an important role in our understanding of the dispersal of Gondwana. Previously proposed reconstruction models often contain overlaps and gaps in the restored margins that reflect difficulties in accurately delineating the continent-ocean boundary (COB) and determining the amount and distribution of extended continental crust. This study focuses on the evolution of the African margin adjacent to the Mozambique Basin and the conjugate margin of Antarctica near the Riiser Larsen Sea. New satellite-derived gravity data have been used to trace the orientations and landward limits of fracture zones in the study area. A 3-D gravity inversion has produced a crustal thickness model that reliably quantifies the extent and amount of stretched crust. Information on crustal thickness along with the identification of fracture zones reveal the COBs that are located significantly closer to the coasts of Africa and Antarctica than previously recognized. Correlation of both fracture zone azimuths and the identified COBs over the conjugate margins suggest Antarctica began drifting away from Africa at approximately 171 Ma in a roughly SSE direction. Of several scenarios examined, the Beira High is most likely oceanic and may be a conjugate feature of the southern Astrid Ridge. An areal-balancing method that involves restoring the crust to a uniform pre-rift thickness has been used to perform the non-rigid reconstruction for both non-volcanic and volcanic margin with magmatic underplating. Based on the results, Africa underwent extension of 65-105 km while Antarctic crust was stretched by 90-190 km. Both margins reveal a trend of increasing extension from east to west. Various models tested to determine the direction of extension during rifting suggest that Antarctica underwent a counter-clockwise rotation with respect to Africa between 186-171 Ma prior to the onset of seafloor spreading.

  13. IRETHERM: Developing a Strategic and Holistic Understanding of Ireland's Geothermal Energy Potential through Integrated Modelling of New and Existing Geophysical, Geochemical and Geological Data

    NASA Astrophysics Data System (ADS)

    Jones, Alan G.; Daly, Stephen; Vozar, Jan; Rath, Volker; Campanya, Joan; Blake, Sarah; Delhaye, Robert; Fritschle, Tobias; Willmot Noller, Nicola; Long, Mike; Waters, Tim

    2015-04-01

    The Science Foundation Ireland funded academia-government-industry collaborative IRETHERM project (www.iretherm.ie), initiated in 2011, is developing a strategic understanding of Ireland's (all-island) deep geothermal energy potential through integrated modelling of new and existing geophysical, geochemical and geological data. Potential applications include both low enthalpy district space heating of large urban centres and electricity generation from intermediate-temperature waters. IRETHERM comprises three broad geothermal target types; 1) Assessment of the geothermal energy potential of Ireland's radiogenic granites (EGS), (2) Assessment of the geothermal energy potential of Ireland's deep sedimentary basins (HSA), and, (3) Assessment of the geothermal energy potential of warm springs. The geophysical subsurface imaging techniques of choice are controlled-source (CSEM) and natural-source (magnetotellurics, MT) electromagnetic methods. Electrical conductivity, being a transport property, is a proxy for permeability, and appropriate porosity-permeability relations are being developed. To date, MT measurements have been made at 466 sites over sedimentary basins (190 sites), granites (156 sites) and warm springs (120 sites), with CSEM across one warm spring. An ongoing continuous geochemical (temperature and electrical conductivity every 15 mins) and time-lapse seasonal hydrochemical sampling programmes are in progress at six warm spring sites. A database on heat production in Irish rocks has been compiled, of more than 3,300 geochemical sample measurements, with 3,000 retrieved from various archives and over 300 new analyses. Geochemistry, geochronology and isotopic analyses have been conducted on subsurface granites and exposed analogues astride the Iapetus Suture Zone in order to understand the underlying reasons for their radiogenic heat production. Finally, thermal conductivity measurements have been made on borehole samples from representative lithologies

  14. Geology of the Round Bay quadrangle, Anne Arundel County, Maryland, with a section on Dinoflagellate-acritarch palynology, and a section on Cretaceous pollen

    USGS Publications Warehouse

    Minard, James Pierson; May, Fred E.; Christopher, Raymond A.

    1980-01-01

    Six Coastal Plain formations and one group crop out in the Round Bay quadrangle near the inner edge of the Atlantic Coastal Plain physiographic province. The quadrangle lies astride the Severn River, in Anne Arundel County, near Annapolis, Md. The seven stratigraphic units aggregate as much as 128 m in outcrop. In ascending order, the units are: the upper part of the Potomac Group and the Magothy, Matawan, and Severn Formations, all of Cretaceous age; the Brightseat and Aquia Formations of Paleocene age and the Calvert Formation of Miocene age. Quaternary deposits are thin and cover only small areas; they are all mapped under one unit. Several small, thin deposits of Tertiary alluvium are mapped separately. The largely unconsolidated Cretaceous and Tertiary formations consist chiefly of quartz, glauconite, clays, muscovite, chlorite, lignite, feldspar, and pyrite. Quaternary sediments are mostly locally derived sands, silts, and clays with some gravel and, in the finer sediments, considerable amounts of organic matter. The Cretaceous and Tertiary units strike generally northeast; the younger the formation, the more easterly it strikes. Dips are gentle, 3.6 to 15 m per kilometer toward the southeast, and decrease upward through the section. The Round Bay quadrangle is near the southern limit of several formations that thin progressively toward the southwest from New Jersey. Some pinch out between Betterton, on the eastern shore of Chesapeake Bay, and Round Bay, on the western shore, whereas others are present only as thin remnants 1-2 m thick. Resources of the quadrangle include abundant ground water, sand, and high land values near water.

  15. Preliminary assessment of the geologic setting, hydrology, and geochemistry of the Hueco Tanks geothermal area, Texas and New Mexico. Geological Circular 81-1

    SciTech Connect

    Henry, C.D.; Gluck, J.K.

    1981-01-01

    The Hueco Tanks geothermal area contains five known but now inactive hot wells (50/sup 0/ to 71/sup 0/C). The area trends north-south along the east side of Tularosa-Hueco Bolson astride the Texas-New Mexico border approximately 40 km northeast of El Paso. Because of its proximity to El Paso, geothermal water in the Hueco Tanks area could be a significant resource. Hueco Bolson is an asymmetric graben. Greatest displacement along boundary faults is on the west side adjacent to the Franklin Mountains. Faults, probably with less displacement, also form an irregular boundary on the east side of the bolson. Several probable faults may allow the rise of thermal waters from depth. Ground water in the central part of Hueco Bolson flows southward to the Rio Grande. However, four of the five hot wells occur in a ground-water trough along the eastern margin of the bolson. The trough may be bounded by one of the postulated faults serving as a barrier to ground-water flow. Data on permeability of potential reservoir rocks, including basin fill and fractured bedrock, suggest that they may be sufficiently permeable for development of geothermal water. The concentration of dissolved solids in the geothermal waters varies from 1100 to at least 12,500 mg/L, but most waters show high concentrations. They are Na-Cl-(SO/sub 4/) waters similar in composition to nonthermal waters in basin fill. The composition probably results from contact with evaporite deposits either in basin fill or in Paleozoic bedrock. Shallow reservoirs reach maximum temperatures of about 80/sup 0/ to 110/sup 0/C. Available data are too limited to evaluate adequately the resource potential of geothermal water in the Hueco Tanks area. A complete exploration program, including geological, hydrological, and geochemical investigation, is recommended.

  16. Spatial analysis from remotely sensed observations of Congo basin of East African high Land to drain water using gravity for sustainable management of low laying Chad basin of Central Africa

    NASA Astrophysics Data System (ADS)

    Modu, B.; Herbert, B.

    2014-11-01

    The Chad basin which covers an area of about 2.4 million kilometer square is one of the largest drainage basins in Africa in the centre of Lake Chad .This basin was formed as a result of rifting and drifting episode, as such it has no outlet to the oceans or seas. It contains large area of desert from the north to the west. The basin covers in part seven countries such as Chad, Nigeria, Central African Republic, Cameroun, Niger, Sudan and Algeria. It is named Chad basin because 43.9% falls in Chad republic. Since its formation, the basin continues to experienced water shortage due to the activities of Dams combination, increase in irrigations and general reduction in rainfall. Chad basin needs an external water source for it to be function at sustainable level, hence needs for exploitation of higher east African river basin called Congo basin; which covers an area of 3.7 million square km lies in an astride the equator in west-central Africa-world second largest river basin after Amazon. The Congo River almost pans around republic of Congo, the democratic republic of Congo, the Central African Republic, western Zambia, northern Angola, part of Cameroun, and Tanzania. The remotely sensed imagery analysis and observation revealed that Congo basin is on the elevation of 275 to 460 meters and the Chad basin is on elevation of 240 meters. This implies that water can be drained from Congo basin via headrace down to the Chad basin for the water sustainability.

  17. Ice-shelf melting around Antarctica

    NASA Astrophysics Data System (ADS)

    Rignot, E.; Jacobs, S.

    2008-12-01

    The traditional view on the mass balance of Antarctic ice shelves is that they loose mass principally from iceberg calving with bottom melting a much lower contributing factor. Because ice shelves are now known to play a fundamental role in ice sheet evolution, it is important to re-evaluate their wastage processes from a circumpolar perspective using a combination of remote sensing techniques. We present area average rates deduced from grounding line discharge, snow accumulation, firn depth correction and ice shelf topography. We find that ice shelf melting accounts for roughly half of ice-shelf ablation, with a total melt water production of 1027 Gt/yr. The attrition fraction due to in-situ melting varies from 9 to 90 percent around Antarctica. High melt producers include the Ronne, Ross, Getz, Totten, Amery, George VI, Pine Island, Abbot, Dotson/Crosson, Shackleton, Thwaites and Moscow University Ice Shelves. Low producers include the Larsen C, Princess Astrid and Ragnhild coast, Fimbul, Brunt and Filchner. Correlation between melt water production and grounding line discharge is low (R2 = 0.65). Correlation with thermal ocean forcing from the ocean are highest in the northern parts of West Antarctica where regressions yield R2 of 0.93-0.97. Melt rates in the Amundsen Sea exhibit a quadratic sensitivity to thermal ocean forcing. We conclude that ice shelf melting plays a dominant role in ice shelf mass balance, with a potential to change rapidly in response to altered ocean heat transport onto the Antarctic continental shelf.

  18. RTOPO-1: A consistent dataset for Antarctic ice shelf topography and global ocean bathymetry

    NASA Astrophysics Data System (ADS)

    Timmermann, Ralph

    2010-05-01

    Sub-ice shelf circulation and freezing/melting rates depend critically on an accurate and consistent representation of cavity geometry (i.e. ice-shelf draft and ocean bathymetry). Existing global or pan-Antarctic data sets have turned out to contain various inconsistencies and inaccuracies. The goal of this work is to compile independent regional fields into a global data set. We use the S-2004 global 1-minute bathymetry as the backbone and add an improved version of the BEDMAP topography for an area that roughly coincides with the Antarctic continental shelf. Locations of the merging line have been carefully adjusted in order to get the best out of each data set. High-resolution gridded data for the Amery, Fimbul, Filchner-Ronne, Larsen C and George VI Ice Shelves and for Pine Island Glacier have been carefully merged into the ambient ice and ocean topographies. Multibeam ship survey data for bathymetry in the former Larsen B cavity and the southeastern Bellingshausen Sea have been obtained from the data centers of Alfred Wegener Institute (AWI), British Antarctic Survey (BAS) and Lamont-Doherty Earth Observatory (LDEO), gridded, and again carefully merged into the existing bathymetry map. The resulting global 1-minute data set contains consistent masks for open ocean, grounded ice, floating ice, and bare land surface. The Ice Shelf Cavern Geometry Team: Anne Le Brocq, Tara Deen, Eugene Domack, Pierre Dutrieux, Ben Galton-Fenzi, Dorothea Graffe, Hartmut Hellmer, Angelika Humbert, Daniela Jansen, Adrian Jenkins, Astrid Lambrecht, Keith Makinson, Fred Niederjasper, Frank Nitsche, Ole Anders Nøst, Lars Henrik Smedsrud, and Walter Smith

  19. Active upper plate thrust faulting in regions of low plate interface coupling, repeated slow slip events, and coastal uplift: Example from the Hikurangi Margin, New Zealand

    NASA Astrophysics Data System (ADS)

    Mountjoy, Joshu J.; Barnes, Philip M.

    2011-01-01

    Contractional fore-arc faulting and deformation is a characteristic feature of many subduction systems. Definition of the three-dimensional geometry and displacement rates of active, upper plate, out-of-sequence thrust faults along ˜250 km of the upper Hikurangi Margin enables us to examine the relationship between fore-arc deformation and the subduction interface in light of interseismic coupling estimates and distribution of slow slip events, both modeled from GPS measurements. These mid-fore-arc structures include the seaward vergent, outer shelf Lachlan and Ariel faults, with vertical separation rates up to 5 mm/yr, and several other major inner shelf faults with rates that are up to 3.8 mm/yr and comparable with Holocene coastal uplift rates. Seismic reflection imaging and geometric projection of these faults at depth indicate that they splay from the region of the plate interface where geodetic inversions for interseismic coupling and slow slip events suggest that the plate boundary undergoes aseismic slip. This observation may indicate either (1) that frictional properties and interseismic coupling on the plate interface are independent and unrelated to the active splay fault deformation in the inner-middle fore arc or (2) that the active splay faulting reflects long-term mechanical coupling related to higher shear stress, or the relative yield strength of the plate interface to the overriding plate, and that the current pattern of interseismic coupling may not be persistent over geological time scales of 20 ka. We compare structure and processes on the northern Hikurangi and Costa Rican margins and find similarities and significant differences astride these subduction systems.

  20. On Perturbation Components Correspondence between Diffusion and Transport

    SciTech Connect

    G. Palmiotti

    2012-11-01

    We have established a correspondence between perturbation components in diffusion and transport theory. In particular we have established the correspondence between the leakage perturbation component of the diffusion theory to that of the group self scattering in transport theory. This has been confirmed by practical applications on sodium void reactivity calculations of fast reactors. Why this is important for current investigations? Recently, there has been a renewed interest in designing fast reactors where the sodium void reactivity coefficient is minimized. In particular the ASTRID8,9 reactor concept has been optimized with this goal in mind. The correspondence on the leakage term that has been established here has a twofold implication for the design of this kind of reactors. First, this type of reactor has a radial reflector; therefore, as shown before, the sodium void reactivity coefficient calculation requires the use of transport theory. The minimization of the sodium reactivity coefficient is normally done by increasing the leakage component that has a negative sign. The correspondence established in this paper allows to directly look at this component in transport theory. The second implication is related to the uncertainty evaluation on sodium void reactivity. As it has shown before, the total sodium void reactivity effect is the result of a large compensation (opposite sign) between the scattering (called often spectral) component and the leakage one. Consequently, one has to evaluate separately the uncertainty on each separate component and then combine them statistically. If one wants to compute the cross section sensitivity coefficients of the two different components, the formulation established in this paper allows to achieve this goal by playing on the contribution to the sodium void reactivity coming from the group self scattering of the sodium cross section.

  1. Permo-Triassic reconstruction of western Pangea and the evolution of the Gulf of Mexico&solCaribbean region

    NASA Astrophysics Data System (ADS)

    Pindell, James; Dewey, John F.

    1982-04-01

    A Permo-Triassic reconstruction of western Pangea (North America, South America, Africa) is proposed that is characterized by (1) definition of the North Atlantic fit by matching of marginal offsets (fracture zones) along the opposing margins, (2) a South Atlantic fit that is tighter than the BuIlard fit and that is achieved by treating Africa as two plates astride the Benue Trough and related structures during the Cretaceous, (3) complete closure of the Proto-Atlantic Ocean between North and South America, accomplished by placing the Yucatan block between the Ouachita Mountains and Venezuela, (4) a proposed Hercynian suture zone that separates zones of foreland thrusting from zones of arc-related magmatic activity; to the northwest of this suture lie the Chortis block and Mexico and most of North America, and to the southeast lie South America, the Yucatan Block, Florida and Africa, and (5) satisfaction of paleomagmatic data from North America, South America, and Africa. Beginning with the proposed reconstruction, the relative motion history of South America with respect of North America is defined by using the finite difference method. Within the framework provided by the proposed relative motion history, an evolutionary model for the development of the Gulf of Mexico and Caribbean region is outlined in a series of 13 plate boundary reconstructions at time intervals from the Jurassic to the present. The model includes (1) formation of the Gulf of Mexico by 140 Ma, (2) Pacific provenance of the Caribbean plate through the North America-South America gap during Cretaceous time, (3) Paleocene-Early Eocene back arc spreading origin for the Yucatan Basin, whereby Cuba is the frontal arc and the Nicaragua Rise-Jamaica-Southern Hispaniola is the remnant arc, and (4) 1200 km of post-Eocene cumulative offset along both the Northern and Southern Caribbean Plate Boundary Zones, allowing large-scale eastward migration of the Caribbean plate with respect to the North and

  2. Distribution and mechanism of Neogene to present-day vertical axis rotations, Pacific-Australian Plate Boundary Zone, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Little, Timothy A.; Roberts, Andrew P.

    1997-01-01

    Remarkably little knowledge exists about mechanisms of vertical axis rotation in continental crust. Steeply dipping basement rocks in South Island, New Zealand, provide an opportunity to map the distribution of rotations across the Pacific-Australian plate boundary zone, and to delineate boundaries of rotated blocks in unusual detail. We synthesize new structural data with new and existing paleomagnetic data, with geodetic data, and with patterns of Neogene-Quaternary faulting in the strike-slip Marlborough fault system. For the past 20 m.y., vertical axis rotations have been hinged about two crustal-scale boundaries near the east coast. The NE hinge accommodated ˜50° of early-middle Miocene clockwise rotation, which caused deformation of the eastern ends of the Alpine-Wairau and Clarence strike-slip faults. The SW hinge has accommodated a further 30°-50° of finite clockwise rotation since ˜4 Ma and deflects active fault traces. The locus of rotation has shifted southwestward astride a subduction margin that is lengthening in that direction. Rotating rocks are pinned to the south against a locked collision zone where the continental Chatham Rise impinges against the margin. Slip on inland strike-slip faults is transformed seaward across a zone of fault termination into rigid body rotation of a large continental block that has been thrust eastward over the downgoing subducted slab of the Pacific plate. The rotation mechanism is a "migrating hinge," which resembles a flexed telephone book. Strike-slip faults are translated through a brecciated hinge region that does not coincide with a fixed material line in the rock.

  3. Mineral resources and mineral resource potential of the Saline Valley and Lower Saline Wilderness Study Areas, Inyo County, California

    SciTech Connect

    Wrucke, C.T.; Marsh, S.P.; Raines, G.L.; Werschky, R.S.; Blakely, R.J.; Hoover, D.B.; McHugh, E.L.; Rumsey, C.M.; Gaps, R.S.; Causey, J.D.

    1984-01-01

    This report presents the results of a mineral survey of the Saline Valley Wilderness Study Area and the Lower Saline Wilderness Study Area, California Desert Conservation Area, Inyo County, California. The Saline Valley Wilderness Study Area and the Lower Saline Wilderness Study Area were studied in 1981-83 using geologic, geochemical, remote sensing, and geophysical surveys and the examination of mines and prospects to evaluate mineral resources and the potential for mineral resources. The Saline Valley Wilderness Study Area has a high potential for the occurrence of gold resources in two areas. One area, largely outside the study area, is in the vicinity of the Crater mine in the Last Chance Range, and it has potential for the occurrence of gold in a disseminated deposit in an epithermal environment. The other area is in Marble Canyon in the western part of the study area, and it has high potential for the occurrence of gold placer deposits. Marble Canyon also has a moderate potential for gold in placer deposits downstream from the area of high potential. Seven areas, scattered from the Inyo Mountains to the Last Chance Range, have a low potential for the occurrence of gold in disseminated deposits, and one area that lies astride the border of Death Valley National Monument has a low potential for the occurrence of gold in vein deposits. The southern end of Eureka Valley has a low potential for the occurrence of lithium and uranium resources in buried sedimentary deposits for the occurrence of lithium and uranium resources in buried sedimentary deposits beneath the valley floor. Demonstrated resources of native sulfur exist at the Crater mine but no resource potential was identified nearby in adtacent parts of the study area. 3 figs. (ACR)

  4. Molecular Epidemiology and Clinical Impact of Acinetobacter calcoaceticus-baumannii Complex in a Belgian Burn Wound Center.

    PubMed

    De Vos, Daniel; Pirnay, Jean-Paul; Bilocq, Florence; Jennes, Serge; Verbeken, Gilbert; Rose, Thomas; Keersebilck, Elkana; Bosmans, Petra; Pieters, Thierry; Hing, Mony; Heuninckx, Walter; De Pauw, Frank; Soentjens, Patrick; Merabishvili, Maia; Deschaght, Pieter; Vaneechoutte, Mario; Bogaerts, Pierre; Glupczynski, Youri; Pot, Bruno; van der Reijden, Tanny J; Dijkshoorn, Lenie

    2016-01-01

    Multidrug resistant Acinetobacter baumannii and its closely related species A. pittii and A. nosocomialis, all members of the Acinetobacter calcoaceticus-baumannii (Acb) complex, are a major cause of hospital acquired infection. In the burn wound center of the Queen Astrid military hospital in Brussels, 48 patients were colonized or infected with Acb complex over a 52-month period. We report the molecular epidemiology of these organisms, their clinical impact and infection control measures taken. A representative set of 157 Acb complex isolates was analyzed using repetitive sequence-based PCR (rep-PCR) (DiversiLab) and a multiplex PCR targeting OXA-51-like and OXA-23-like genes. We identified 31 rep-PCR genotypes (strains). Representatives of each rep-type were identified to species by rpoB sequence analysis: 13 types to A. baumannii, 10 to A. pittii, and 3 to A. nosocomialis. It was assumed that isolates that belonged to the same rep-type also belonged to the same species. Thus, 83.4% of all isolates were identified to A. baumannii, 9.6% to A. pittii and 4.5% to A. nosocomialis. We observed 12 extensively drug resistant Acb strains (10 A. baumannii and 2 A. nosocomialis), all carbapenem-non-susceptible/colistin-susceptible and imported into the burn wound center through patients injured in North Africa. The two most prevalent rep-types 12 and 13 harbored an OXA-23-like gene. Multilocus sequence typing allocated them to clonal complex 1 corresponding to EU (international) clone I. Both strains caused consecutive outbreaks, interspersed with periods of apparent eradication. Patients infected with carbapenem resistant A. baumannii were successfully treated with colistin/rifampicin. Extensive infection control measures were required to eradicate the organisms. Acinetobacter infection and colonization was not associated with increased attributable mortality. PMID:27223476

  5. On the highly inclined vW leptokurtic asteroid families

    NASA Astrophysics Data System (ADS)

    Carruba, V.; Domingos, R. C.; Aljbaae, S.; Huaman, M.

    2016-08-01

    vW leptokurtic asteroid families are families for which the distribution of the normal component of the terminal ejection velocity field vW is characterized by a positive value of the γ2 Pearson kurtosis, i.e., they have a distribution with a more concentrated peak and larger tails than the Gaussian one. Currently, eight families are known to have γ2(vW) > 0.25. Among these, three are highly inclined asteroid families, the Hansa, Barcelona, and Gallia families. As observed for the case of the Astrid family, the leptokurtic inclination distribution seems to be caused by the interaction of these families with node secular resonances. In particular, the Hansa and Gallia family are crossed by the s - sV resonance with Vesta, that significantly alters the inclination of some of their members. In this work we use the time evolution of γ2(vW) for simulated families under the gravitational influence of all planets and the three most massive bodies in the main belt to assess the dynamical importance (or lack of) node secular resonances with Ceres, Vesta, and Pallas for the considered families, and to obtain independent constraints on the family ages. While secular resonances with massive bodies in the main belt do not significantly affect the dynamical evolution of the Barcelona family, they significantly increase the γ2(vW) values of the simulated Hansa and Gallia families. Current values of the γ2(vW) for the Gallia family are reached over the estimated family age only if secular resonances with Vesta are accounted for.

  6. Split from slip and schist: Crustal anisotropy beneath northern Cascadia from non-volcanic tremor

    NASA Astrophysics Data System (ADS)

    Bostock, M. G.; Christensen, N. I.

    2012-08-01

    Polarization and splitting analyses of minute-long windows of non-volcanic tremor at 3-component stations in the vicinity of southern Vancouver Island provide new evidence for the presence of anisotropy within the crustal portion of the North American plate beneath Cascadia. As reported previously, tremor particle motions are predominantly horizontal and inferred to manifest an upgoing wavefield composed primarily of S-waves. Under this assumption, estimates of incidence angle and back azimuth can be deduced from orientation of the smallest principle direction of motion. When subjected to standard S-wave splitting analysis, most stations yield systematic and reproducible fast polarization directions. Estimates of original polarization direction are more scattered and splitting times often exhibit multimodal distributions. Numerical simulations, wherein band-limited synthetic seismograms comprising contributions from multiple sources are analyzed for splitting, neatly reproduce these characteristics and thereby provide a framework for interpretation. A number of stations in our study sit astride the San Juan fault which, based on reflection studies, dips approximately 60 to 70° to the north. Underlying these stations is the Leech River Complex consisting of strongly foliated greenschist facies phyllites with steeply dipping foliations striking parallel to fast polarization directions of split S-waves. Detailed laboratory velocity measurements at elevated pressures show that as little as 2 to 3 km of vertically dipping Leech River phyllite are required to produce the observed splitting. These phyllites have some of the highest S-wave anisotropies measured to date and are part of a once continuous belt of anisotropic crust extending over 2000 km along the western North American coast from southern Vancouver Island to southwest Alaska.

  7. Molecular Epidemiology and Clinical Impact of Acinetobacter calcoaceticus-baumannii Complex in a Belgian Burn Wound Center

    PubMed Central

    Bilocq, Florence; Jennes, Serge; Verbeken, Gilbert; Rose, Thomas; Keersebilck, Elkana; Bosmans, Petra; Pieters, Thierry; Hing, Mony; Heuninckx, Walter; De Pauw, Frank; Soentjens, Patrick; Merabishvili, Maia; Deschaght, Pieter; Vaneechoutte, Mario; Bogaerts, Pierre; Glupczynski, Youri; Pot, Bruno; van der Reijden, Tanny J.; Dijkshoorn, Lenie

    2016-01-01

    Multidrug resistant Acinetobacter baumannii and its closely related species A. pittii and A. nosocomialis, all members of the Acinetobacter calcoaceticus-baumannii (Acb) complex, are a major cause of hospital acquired infection. In the burn wound center of the Queen Astrid military hospital in Brussels, 48 patients were colonized or infected with Acb complex over a 52-month period. We report the molecular epidemiology of these organisms, their clinical impact and infection control measures taken. A representative set of 157 Acb complex isolates was analyzed using repetitive sequence-based PCR (rep-PCR) (DiversiLab) and a multiplex PCR targeting OXA-51-like and OXA-23-like genes. We identified 31 rep-PCR genotypes (strains). Representatives of each rep-type were identified to species by rpoB sequence analysis: 13 types to A. baumannii, 10 to A. pittii, and 3 to A. nosocomialis. It was assumed that isolates that belonged to the same rep-type also belonged to the same species. Thus, 83.4% of all isolates were identified to A. baumannii, 9.6% to A. pittii and 4.5% to A. nosocomialis. We observed 12 extensively drug resistant Acb strains (10 A. baumannii and 2 A. nosocomialis), all carbapenem-non-susceptible/colistin-susceptible and imported into the burn wound center through patients injured in North Africa. The two most prevalent rep-types 12 and 13 harbored an OXA-23-like gene. Multilocus sequence typing allocated them to clonal complex 1 corresponding to EU (international) clone I. Both strains caused consecutive outbreaks, interspersed with periods of apparent eradication. Patients infected with carbapenem resistant A. baumannii were successfully treated with colistin/rifampicin. Extensive infection control measures were required to eradicate the organisms. Acinetobacter infection and colonization was not associated with increased attributable mortality. PMID:27223476

  8. Tsunami Hazard Assessment in New Zealand Ports and Harbors

    NASA Astrophysics Data System (ADS)

    Borrero, J. C.; Wotherspoon, L.; Power, W. L.; Goring, D.; Barberopoulou, A.; Melville, B.; Shamseldin, A.

    2012-12-01

    The New Zealand Ministry of Science and Innovation (MSI) has sponsored a 3-year collaborative project involving industry, government and university research groups to better assess and prepare for tsunami hazards in New Zealand ports and harbors. As an island nation, New Zealand is highly dependent on its maritime infrastructure for commercial and recreational interests. The recent tsunamis of 2009, 2010 and 2011 (Samoa, Chile and Japan) highlighted the vulnerability of New Zealand's marine infrastructure to strong currents generated by such far field events. These events also illustrated the extended duration of the effects from such tsunamis, with some of the strongest currents and highest water levels occurring many hours, if not days after the tsunami first arrival. In addition, New Zealand also sits astride the Tonga-Kermadec subduction zone, which given the events of recent years, cannot be underestimated as a major near field hazard. This presentation will discuss the modeling and research strategy that will be used to mitigate tsunami hazards in New Zealand ports and harbors. This will include a detailed time-series analysis (including Fourier and discrete Wavelet techniques) of water levels recorded throughout New Zealand form recent tsunami events (2009 Samoa, 2010 Chile and 2011 Japan). The information learned from these studies will guide detailed numerical modeling of tsunami induced currents at key New Zealand ports. The model results will then be used to guide a structural analysis of the relevant port structures in terms of hydrodynamic loads as well as mooring and impact loads due to vessel and/or debris. Ultimately the project will lead to an improvement in New Zealand's tsunami response plans by providing a decision making flow chart, targeted for marine facilities, to be used by emergency management officials during future tsunami events.Tsunami effects at Port Charles, New Zealand: (top) inundation into a neighborhood and (bottom left and right

  9. Was the Palaeo-Tethys Responsible for Ending the Palaeozoic?

    NASA Astrophysics Data System (ADS)

    Sengor, A. C.; Atayman, S.

    2008-12-01

    When Pangaea was assembled during the course of the late Palaeozoic, a triangular oceanic space was left between Laurasia and Gondwana-Land. This space has been called the Palaeo-Tethys and long believed to have always been a giant gulf of the Panthalassa. However, stratigraphical/structural, palaeontological and palaeomagnetic data clearly show that the Palaeo-Tethys was separated by a land bridge, called the Cathaysian Bridge, from the Panthalassa. By later medial to late Permian time no deep-water connexion had remained between the two oceans and the Palaeo-Tethys acquired the character of an inland sea of Pangaea. This restriction, its location astride the Permian equator, the endorheic drainage of Pangaea towards it and the increasing aridity of the Permian world, led to the development of anoxic conditions in the Palaeo-Tethys. This anoxia occupied the abyssal areas by the Guadalupian, reached the lower shelves by the Wuchiapingian and occupied the entire Palaeo-Tethys by the end of the Changhsingian. This led to widespread decimation of the benthic organisms in these areas and in that order. Evidence of gas-release- caused submarine erosion surfaces, anomalous increase in chemical weathering onland and a 2000-km-wide halo of fungal spikes indicating the presence of abundant dead organic matter surrounding the Palaeo- Tethys suggest that it may have erupted toxic gases to kill the terrestrial organisms in its vicinity, including the airborn insects. This was the only time in the Phanerozoic that the insects experienced significant extinction. The Permian extinction was not global but was confined to the Palaeo-Tethys, its surroundings, and other marine areas it could pollute. Since these areas constituted some 90% by biodiversity of the niches in the Permian, decimation of their inhabitants created an impression of universal extinction. In boreal and austral areas (except around the Gulf of Malagasy penetrating deep into Gondwana-Land from the Palaeo

  10. A fresh look at the Sun, from core to corona, illuminated by new insight on the physics of gravitation

    NASA Astrophysics Data System (ADS)

    Osmaston, M. F.

    2013-09-01

    The Sun is a testing ground for many kinds of physical understanding but an understanding of the physical mechanism of gravitation, the driver of all its machinery, has been lacking. Newton's work on gravitation astride the end of the 17th century concentrated on the behaviour of the force, not upon its origin. But he already endorsed the idea of an ubiquitously intervening aether to convey the force and, as Huygens had already reasoned, also to transmit light waves. Then, in the 1860s, Maxwell [1] and Thompson (Kelvin) [2] started to think of fundamental particles as being aether in a vortex-like motion which would, by mutual attraction, provide their mass property and gravitation. In such a set-up, not only will particles and the aether around them not be dynamically independent, as the Michelson-Morley experiment actually demonstrated 20 years later, but the aether will be in a related degree of random motion. Importantly, that motion will cause the scattering of transmitted radiation. But, in setting up Relativity (1905-1916), Einstein made further enquiry impossible. General Relativity treats particles as infinitesimal entities, and supposes, evasively, that the mass is 'intrinsic' to that specific infinitesimal point in space. This denies them any volume in which to develop their individual external mass property and has discouraged any attempt at physical understanding of its development. Nevertheless, there is now firm evidence that electrons, positrons and protons do have finite size. So, building on the original thinking of Maxwell and Thompson, supported later by [3], my inquiry as to the nature of the physical mechanism by which gravitational force is developed has led me to the surprising finding that the Newtonian potential is inevitably always accompanied by a corresponding positive-body-repelling radial electric field. I have called this the Gravity-Electric (G-E) field and have adduced evidence for its action at many astronomical scales [4 - 7]. So

  11. ASEAN.

    PubMed

    1986-04-01

    Focus in this discussion of the 6 Association of South East Asian Nations (ASEAN) (Brunei, Indonesia, Malaysia, Philippines, Singapore, and Thailand) is on the following: georgraphy; the people; history; institutions (foreign ministers' meetings, economic ministers' meetings, the ASEAN Secretariat, and the Task Force on the Future of ASEAN cooperation): the economy; defense; external relations; and relations between the US and the ASEAN nations. In mid-1985 the population totaled 289.5 million with an average (unweighted) annual growth rate of 2.2%. Located on the Southeast Asian peninsula and the islands to the south and east in the South China Sea, the 6 ASEAN states guard some of the most important sealanes in the world. The ASEAN states lie astride the Equator and extend from roughly 1600 km north to 804 km south. 1 of the most striking characteristics of ASEAN is its wide diversity in race, language, culture, and religion; many ethnic groups coexist. Malayo-Polyneian make up the majority in the Philippines, Malaysia, and Indonesia (and thus in ASEAN), although Malaysia and Indonesia have significant numbers of other groups. Thailand is 75% Thai. Ethnic Chinese make up 77% of the population of Singapore, and sizable Chinese minorities are found in each of the other ASEAN nations. ASEAN founded officially on August 8, 1967, was created to strengthen regional cohesion and self-reliance through economic, social, and cultural cooperation. The organization developed slowly during its 1st decade, due in part to differing economic interests, varied historical experience, and the initially fragile political ties among the 5 original states. The Vietnamese invasion of Cambodia, starting in December 1978, was a further stimulus to collaboration. The ASEAN nations successfully managed passage of UN resolutions condemning Vietnam and were the chief sponsors in the July 1981 International Conference on Kampuchea. Although ASEAN was established with primarily economic and

  12. 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

  13. Shenandoah National Park, Virginia, Shaded Relief with Height as Color

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Shenandoah National Park lies astride part of the Blue Ridge Mountains, which form the southeastern range of the greater Appalachian Mountains in Virginia. The park is well framed by this one-degree of latitude (38-39 north) by one-degree of longitude (78-79 west) cell of Shuttle Radar Topography Mission data, and it appears here as the most prominent ridge trending diagonally across the scene. Skyline Drive, a 169-kilometer (105-mile) road that winds along the crest of the mountains through the length the park, provides vistas of the surrounding landscape. The Shenandoah River flows through the valley to the west, with Massanutten Mountain standing between the river's north and south forks. Unusually pronounced meanders of both river forks are very evident near the top center of this scene. Massanutten Mountain itself is an unusually distinctive landform also, consisting of highly elongated looping folds of sedimentary rock. The rolling Piedmont country lies to the southeast of the park, with Charlottesville located at the bottom center of the scene.

    Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to bluish-white at the highest elevations.

    Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers

  14. Earthquake probabilities in the San Francisco Bay Region: 2000 to 2030 - a summary of findings

    USGS Publications Warehouse

    Working Group on California Earthquake Probabilities

    1999-01-01

    The San Francisco Bay region sits astride a dangerous “earthquake machine,” the tectonic boundary between the Pacific and North American Plates. The region has experienced major and destructive earthquakes in 1838, 1868, 1906, and 1989, and future large earthquakes are a certainty. The ability to prepare for large earthquakes is critical to saving lives and reducing damage to property and infrastructure. An increased understanding of the timing, size, location, and effects of these likely earthquakes is a necessary component in any effective program of preparedness. This study reports on the probabilities of occurrence of major earthquakes in the San Francisco Bay region (SFBR) for the three decades 2000 to 2030. The SFBR extends from Healdsberg on the northwest to Salinas on the southeast and encloses the entire metropolitan area, including its most rapidly expanding urban and suburban areas. In this study a “major” earthquake is defined as one with M≥6.7 (where M is moment magnitude). As experience from the Northridge, California (M6.7, 1994) and Kobe, Japan (M6.9, 1995) earthquakes has shown us, earthquakes of this size can have a disastrous impact on the social and economic fabric of densely urbanized areas. To reevaluate the probability of large earthquakes striking the SFBR, the U.S. Geological Survey solicited data, interpretations, and analyses from dozens of scientists representing a wide crosssection of the Earth-science community (Appendix A). The primary approach of this new Working Group (WG99) was to develop a comprehensive, regional model for the long-term occurrence of earthquakes, founded on geologic and geophysical observations and constrained by plate tectonics. The model considers a broad range of observations and their possible interpretations. Using this model, we estimate the rates of occurrence of earthquakes and 30-year earthquake probabilities. Our study considers a range of magnitudes for earthquakes on the major faults in the

  15. The urban heat island of a tropical coastal city: the case of Muscat, Oman

    NASA Astrophysics Data System (ADS)

    Charabi, Yassine

    2010-05-01

    Muscat, the capital of the Sultanate of Oman (23° 25'N and 57°00 E), it extended along a coastline that runs around 200 km along the Gulf of Oman. By virtue of its position astride the Tropic of Cancer, Muscat city is located in an arid environment with scanty rainfall, and a dry, hot climate with high evaporation rate. The study area is exposed regularly to sea breeze circulation during day time, while very weak land breeze turning to calm conditions at night. The city is situated in complex and varying topography; the Mountains and hills of the eastern Hajar chain border the city from the south and west and, sometimes, they join the sea in the form of rough slopes and coarse cliffs particularly alongside the eastern coastal fringe. Muscat city witnessed a spectacular socioeconomic development since 1970, stimulated by oil exploration and production. The primacy given to the capital triggered an unprecedented demographic rush. The new developments led to the growth of population size from 56 to 236 thousand in one decade (1970-1980) with an enormous annual growth rate of 12.3 %. This sustained growth raised the population of Muscat to more than 549 thousand in 1993 to 796 thousand in 2007 constituting, thus, 27 % of the total population in Oman. Most of Muscat built-up area is characterized by a high sky-view factor, even in the city centre, except for the CDB area of Riwi, where some of the buildings are over ten stories high. The old city of Muscat and Mutrah is extremely compact with very low sky-view factor. The buildings are two to three stories high. The streets are narrow and cut deep canyons through the old city. The street net work is irregular which increases the mutual shading by buildings. The specific attributes of Muscat, has motivated the elaboration of a multidisciplinary research in sultan Qaboos University (Sultanate of Oman), about the urban climate and air pollution in Muscat city: Multi-scale approach. This paper presents the results of the

  16. Austria.

    PubMed

    1983-08-01

    This discussion of Austria focuses on the following: geography, people, history, government, political conditions, economy, foreign relations, and relations between the US and Austria. As of July 1982, the population of Austria totaled 7.6 million with an annual growth rate of 0.1%. The infant mortality rate is 16/1000, and life expectancy is 73 years. Austria is primarily mountainous, and the climate is moderate. 99% of Austria's population are native German speakers. The only 2 significant minority groups are about 20,000 Slovenes in Carinthia and about 25,000 Croatians in Burgenland. The Austro-Hungarian Empire played a decisive role in central European history, partly because of its strategic position astride the southeast approaches to western Europe and the north-south routes between Germany and Italy. The president of Austria is directly elected to a 6-year term and may not serve more than 2 successive terms. As chief of state, the president's functions are largely representational. The chancellor (head of government) is either the leader of the party that wins the majority of seats in parliamentary elections and therefore can form a government or a coalition, or the leader of the party having the support of the president in the formation of a minority government. The chancellor selects the cabinet and, with its assistance, weilds actual power and is responsible to the Federal Assembly. The Federal Assembly (parliament) is composed of 2 houses--the National Council, or lower house, and the Federal Council, or upper house. Virtually all legislative authority is concentrated in the National Council. Since World War 2 Austria has enjoyed politcal stability. The 2 major parties that formed during the 1945-66 period have the support of about 90% of the electorate. Austria has a free enterprise economy in which the government plays an important role. More than half of the gross domestic product (GDP) comes from manufacturing and services. Austrian farms are small

  17. Efficacy of baby-CIMT: study protocol for a randomised controlled trial on infants below age 12 months, with clinical signs of unilateral CP

    PubMed Central

    2014-01-01

    Background Infants with unilateral brain lesions are at high risk of developing unilateral cerebral palsy (CP). Given the great plasticity of the young brain, possible interventions for infants at risk of unilateral CP deserve exploration. Constraint-induced movement therapy (CIMT) is known to be effective for older children with unilateral CP but is not systematically used for infants. The development of CIMT for infants (baby-CIMT) is described here, as is the methodology of an RCT comparing the effects on manual ability development of baby-CIMT versus baby-massage. The main hypothesis is that infants receiving baby-CIMT will develop manual ability in the involved hand faster than will infants receiving baby-massage in the first year of life. Method and design The study will be a randomised, controlled, prospective parallel-group trial. Invited infants will be to be randomised to either the baby-CIMT or the baby-massage group if they: 1) are at risk of developing unilateral CP due to a known neonatal event affecting the brain or 2) have been referred to Astrid Lindgren Children’s Hospital due to asymmetric hand function. The inclusion criteria are age 3–8 months and established asymmetric hand use. Infants in both groups will receive two 6-weeks training periods separated by a 6-week pause, for 12 weeks in total of treatment. The primary outcome measure will be the new Hand Assessment for Infants (HAI) for evaluating manual ability. In addition, the Parenting Sense of Competence scale and Alberta Infant Motor Scale will be used. Clinical neuroimaging will be utilized to characterise the brain lesion type. To compare outcomes between treatment groups generalised linear models will be used. Discussion The model of early intensive intervention for hand function, baby-CIMT evaluated by the Hand Assessment for Infants (HAI) will have the potential to significantly increase our understanding of how early intervention of upper limb function in infants at risk of

  18. Source Mechanisms, Velocity Structures and Himalaya Tectonics

    NASA Astrophysics Data System (ADS)

    Wu, F. T.; Sheehan, A. F.; Huang, G.; Monsalve, G.

    2003-12-01

    The Himalayan Nepal-Tibet Seismic Experiment (HIMNT; in a region bounded by 26.7 and 29.5 degrees N latitudes and 85 and 88 degrees E longitudes) produced, for the first time, broadband seismic data appropriate for determining earthquake and lithospheric characteristics with a local network astride as well as along the high Himalaya. A suite of studies are being conducted in an attempt to gain subsurface information for a better understanding of the orogenic processes that produced the mountain range. First, it is somewhat surprising that of the 20 earthquakes (M>3.5) for which we are able to use waveform inversion to derive focal mechanisms the great majority of them are tensile types with generally EW oriented T-axes. Some of these events are shallow (~20 km) crustal events and a few are deeper crustal or even upper mantle ones (50-80 km). Several of them appear to be related to the N-S trending graben structures at the surface. Initial attempts at tomography yield structures that generally agree with the the results of receiver function analyses (Schulte-Pelkum, this meeting), with a crust of about 45 km under southern Himalaya and much thicker under the Nothern Himalaya in Tibet. The relocated seismicity using hypoDD (this paper and Monsalve et al., this meeting) lie in well-defined zones. In the region around Mount Everest a zone dips at shallow angle (< 10 degrees) from the Greater Himalaya toward the south can be seen. Under the low foothills in south Nepal steep dipping zones between 30 and 60 km are found in some sections. The seismicity in the upper crust (<30 km) under the high Himalayan range is notable in places but under the eastern part of our network deeper crustal (60 < h < 80 km) concentrate without much shall seismicity. While the shallow (~20 km) reflector from the receiver function analyses can be interpreted as the presence of Indian lithosphere and lends support to the INDEPTH model, the interpretation of seismicity and focal mechanisms

  19. Silicate liquid immiscibility in magmas and in the system K2O-FeO-AI2O3-SiO2: an example of serendipity

    USGS Publications Warehouse

    Roedder, E.

    1978-01-01

    The concept of silicate liquid immiscibility was invoked early in the history of petrology to explain certain pairs of compositionally divergent rocks, but. as a result of papers by Greig (Am. J. Sci. 13, 1-44, 133-154) and Bowen (The Evolution of the Igneous Rocks), it fell into disfavor for many years. The discovery of immiscibility in geologically reasonable temperature ranges and compositions in experimental work on the system K2O-FeO-Al2O3-SiO2, and of evidence for immiscibility in a variety of lunar and terrestrial rocks, has reinstated the process. Phase equilibria in the high-silica corner of the tetrahedron representing the system K2O- FeO-Al2O3-SiO2 are presented, in the form of constant FeO sections through the tetrahedron, at 10% increments. Those sections, showing the tentative relationships of the primary phase volumes, are based on 5631 quenching runs on 519 compositions, made in metallic iron containers in pure nitrogen. Thirteen crystalline compounds are involved, of which at least six show two or more crystal modifica-tions. Two separate phase volumes, in each of which two immiscible liquids, one iron-rich and the other iron-poor, are present at the liquidus. One of these volumes is entirely within the quaternary system, astride the 1:1 K2O:Al2O3 plane. No quaternary compounds as such have been found, but evidence does point toward at least partial quaternary solid solution, with rapidly lowering liquidus temperatures, from K2O??Al2O3?? 2SiO2 ('potash nepheline', kalsilite. kaliophilite) to the isostructural compound K2O??FeO??3SiO2, and from K2O??Al2O3??4SiO2 (leucite) to the isostructural compound K2O??FeO??5SiO2, Both of these series apparently involve substitution, in tetrahedral coordination. of a ferrous iron and a silicon ion for two aluminum ions. Some of the 'impurities' found in analyses of the natural phases may reflect these substitutions. As a result of the geometry of the immiscibility volume located entirely within the quaternary

  20. Unraveling the geodynamic evolution and tectonic history of the Guatemala Suture Zone: a world-class natural laboratory

    NASA Astrophysics Data System (ADS)

    Flores, K. E.; Brocard, G. Y.; Harlow, G. E.

    2013-12-01

    The Guatemala Suture Zone (GSZ) is the fault-bound region in central Guatemala that contains the present North American-Caribbean plate boundary. It is bounded by the Maya Block to the north and by the Chortís Block to the south. This major composite geotectonic unit contains a variety of ophiolites, serpentinite mélanges, and metavolcano-sedimentary sequences along with high-grade schist, gneisses, low-grade metasediments and metagranites thrusted north and south of the active Motagua fault system (MFS). This modern plate boundary has accommodated at least ~1100 km of left-lateral strike-slip motion over the Cenozoic and brings into contact the geological provinces described above. Classically, the GSZ has been interpreted as the result of a single progressive collision of a Chortís Block-related island arc with the passive margin of the Maya Block. This model was based on geochemical signatures of basaltic rocks in oceanic crust sequences both north and south of the MFS. However, results from our research challenge this single collision hypothesis. Oceanic and continental high-pressure-low-temperature (HP-LT) rocks astride the MFS have recorded multiple tectonic events revealed by their multiple metamorphic ages (Sm-Nd, U-Pb and Ar-Ar) and distinct PT paths. These tectonic events differ in age north and south of the MFS. Moreover, the continental and oceanic sequences across the MFS are geochemically and stratigraphically distinct, suggesting different tectonic origins. The southern margin of the Maya Block and the northern section of the GSZ can be clearly interpreted as a Cretaceous-Paleocene flexural passive margin tectonically overridden by ultramafic rocks and a Cretaceous island arc sequence. In contrast, the southern section of the GSZ is composed of a Carboniferous-Jurassic active margin tectonically imbricated with ultramafic rocks and a circum-Pacific Jurassic MORB and IAT metavolcano-sedimentary sequence. Thus, based on these results, we identify at

  1. Removal of daytime thermal deformations in the GBT active surface via out-of-focus holography

    NASA Astrophysics Data System (ADS)

    Hunter, T. R.; Mello, M.; Nikolic, B.; Mason, B. S.; Schwab, F. R.; Ghigo, F. D.; Dicker, S. R.

    2009-01-01

    The 100-m diameter Green Bank Telescope (GBT) was built with an active surface of 2209 actuators in order to achieve and maintain an accurate paraboloidal shape. While much of the large-scale gravitational deformation of the surface can be described by a finite element model, a significant uncompensated gravitational deformation exists. In recent years, the elevation-dependence of this residual deformation has been successfully measured during benign nighttime conditions using the out-of-focus (OOF) holography technique (Nikolic et al, 2007, A&A 465, 685). Parametrized by a set of Zernike polynomials, the OOF model correction was implemented into the active surface and has been applied during all high frequency observations since Fall 2006, yielding a consistent gain curve that is constant with elevation. However, large-scale thermal deformation of the surface has remained a problem for daytime high-frequency observations. OOF holography maps taken throughout a clear winter day indicate that surface deformations become significant whenever the Sun is above 10 degrees elevation, but that they change slowly while tracking a single source. In this paper, we describe a further improvement to the GBT active surface that allows an observer to measure and compensate for the thermal surface deformation using the OOF technique. In order to support high-frequency observers, "AutoOOF" is a new GBT Astrid procedure that acquires a quick set of in-focus and out-of-focus on-the-fly continuum maps on a quasar using the currently active receiver. Upon completion of the maps, the data analysis software is launched automatically which produces and displays the surface map along with a set of Zernike coefficients. These coefficients are then sent to the active surface manager which combines them with the existing gravitational Zernike terms and FEM in order to compute the total active surface correction. The end-to-end functionality has been tested on the sky at Q-Band and Ka

  2. Experimental Determination of Electromagnetic Propagation and Scattering Properties of Ice-Sheets at P-Band

    NASA Astrophysics Data System (ADS)

    Lin, Chung-Chi; Rommen, Björn; Buck, Christopher; Casal, Tania; Dall, Jørgen; Kusk, Anders; Nielsen, Ulrik; Corr, Hugh; Ginestet, Arnaud; Decerprit, Guillaume; Walker, Nick; Kristensen, Steen S.

    2014-05-01

    The electromagnetic (EM) propagation and scattering properties of the ice and its inclusions strongly affect radar reception signals in radio echo sounding of ice-sheets. In particular, those properties are very strongly dependent on the sensing frequency, with penetration depth rapidly decreasing with increasing frequency. Furthermore, the surface scattering signals, which mask the radar echoes from the depth, increases monotonically with frequency. In spite of those drawbacks, the recent interests in the use of P-band (435 MHz), as compared to the more established sensing frequencies at 60 and 150 MHz, are driven mainly by two reasons: (1) the use of a shorter wavelength improves the spatial selectivity of the sensor as a reasonably sized antenna system could generate narrow beams; (2) P-band is the lowest frequency band allocated for active sensing from space, potentially adequate for satellite-based sounding of ice-sheets. New datasets acquired by P-band radar sounders are becoming available, e.g. from the systems built by University of Kansas and ESA's POLARIS instrument built by Technical University of Denmark, thus opening a possibility to quantitatively compare the merits and drawback of ice sounding at P-band. This paper will report the result of the analysis carried out on the POLARIS data which were acquired over East Antarctica in Feb. 2011 in the frame of the Danish IceGrav 2011 campaign. More specifically, ice sounding measurements were performed over the areas of Dronning/Queen Maud Land and its coastal ice-shelves (e.g. Princess Astrid Coast and Fimbul ice-shelf), and Adelaide Island. Different ice types and regimes have been covered in order to build up a comprehensive catalogue of the ice electromagnetic properties. In addition to the POLARIS data, some in-situ data on the surface roughness, ice core data from EPICA and ice-shelf basal roughness data from an upward looking sonar experiment (Autosub Under Ice programme, 2005) have been gathered

  3. Defeating Earthquakes

    NASA Astrophysics Data System (ADS)

    Stein, R. S.

    2012-12-01

    The 2004 M=9.2 Sumatra earthquake claimed what seemed an unfathomable 228,000 lives, although because of its size, we could at least assure ourselves that it was an extremely rare event. But in the short space of 8 years, the Sumatra quake no longer looks like an anomaly, and it is no longer even the worst disaster of the Century: 80,000 deaths in the 2005 M=7.6 Pakistan quake; 88,000 deaths in the 2008 M=7.9 Wenchuan, China quake; 316,000 deaths in the M=7.0 Haiti, quake. In each case, poor design and construction were unable to withstand the ferocity of the shaken earth. And this was compounded by inadequate rescue, medical care, and shelter. How could the toll continue to mount despite the advances in our understanding of quake risk? The world's population is flowing into megacities, and many of these migration magnets lie astride the plate boundaries. Caught between these opposing demographic and seismic forces are 50 cities of at least 3 million people threatened by large earthquakes, the targets of chance. What we know for certain is that no one will take protective measures unless they are convinced they are at risk. Furnishing that knowledge is the animating principle of the Global Earthquake Model, launched in 2009. At the very least, everyone should be able to learn what his or her risk is. At the very least, our community owes the world an estimate of that risk. So, first and foremost, GEM seeks to raise quake risk awareness. We have no illusions that maps or models raise awareness; instead, earthquakes do. But when a quake strikes, people need a credible place to go to answer the question, how vulnerable am I, and what can I do about it? The Global Earthquake Model is being built with GEM's new open source engine, OpenQuake. GEM is also assembling the global data sets without which we will never improve our understanding of where, how large, and how frequently earthquakes will strike, what impacts they will have, and how those impacts can be lessened by

  4. Fingerprints of collisionless reconnection at the separator, I, Ambipolar-Hall signatures

    NASA Astrophysics Data System (ADS)

    Scudder, J. D.; Mozer, F. S.; Maynard, N. C.; Russell, C. T.

    2002-10-01

    Plasma, electric, and magnetic field data on the Polar spacecraft have been analyzed for the 29 May 1996 magnetopause traversal searching for evidence of in situ reconnection and traversal of the separator. In this paper we confine our analysis to model-free observations and intrasensor coherence of detection of the environs of the separator. (1) We illustrate the first documented penetration of the separator of collisionless magnetic reconnection in temporal proximity to successful Walén tests with opposite slopes. (2) We present the first direct measurements of E∥ at the magnetopause. (3) We make the first empirical argument that E∥ derives from the electron pressure gradient force. (4) We document the first detection of the electron pressure ridge astride the magnetic depression that extends from the separator. (5) We provide the first empirical detection of the reconnection rate at the magnetopause with the locally sub-Alfvénic ion inflow, MAi ≃ 0.1, and trans-Alfvénic exhaust at high electron pressure of MiA ≃ 1.1-5. (6) We exhibit the first empirical detection of supra-Alfvénic electron flows parallel to B in excess of 5 in narrow sheets. (7) We illustrate the detection of heat flux sheets indicative of separatrices near, but not always in superposition, with the supra-Alfvénic parallel electron bulk flows. (8) We present the first evidence that pressure gradient scales are short enough to explain the electron fluid's measured cross-field drifts not explained by E × B drift but predicted by the measured size of E∥. (9) We illustrate that the size of the observed E∥ is well organized with the limit implied by Vasyliunas's analysis of the generalized Ohm's law of scale length ?, indicative of the intermediate scale of the diffusion region. (10) We document the first detection of departure from electron gyrotropy not only at the separator crossing but also in its vicinity, an effect presaged by [1975]. (11) We make the first reports of very

  5. Late Cenozoic sedimentation in Pilot Knob Valley, California

    NASA Astrophysics Data System (ADS)

    Rittase, W. M.; Walker, J. D.; Kirby, E.; Andrew, J.; Wan, E.

    2012-12-01

    In Pilot Knob Valley (PKV), active inversion of a Pliocene-mid Pleistocene basin presents the opportunity to understand the spatial and temporal development of an enigmatic basin astride a major transform boundary in California. Here, a ~1000-m-thick package of exposed Late Cenozoic strata has been uplifted and tilted to the northeast. Based on new age and provenance data, we adopt the name Pilot Knob formation (PKfm) to describe much of these exposed rocks north of the Garlock fault (GF) and east of Christmas Canyon gate. Post-Miocene development of PKV is strongly influenced by the sinistral GF, the newly identified Marine Gate fault (MGF) and dextral Eastern California shear zone. The PKfm consists of three lithofacies members, from base to top: (1) rocks derived from Eagle Crags to the south; (2) Randsburg Wash lacustrine rocks; and (3) an upper member derived from the Slate Range. Tephrochronologic data from four PKfm ash samples brackets deposition of lacustrine Randsburg Wash Member rocks between 3.7-3.1 Ma and lacustrine rocks of the Slate Range Member between 1.2-0.6 Ma. A fifth tephrochronologic sample from lacustrine-distal alluvial sediments south of the GF near Christmas Canyon brackets deposition of a possible PKfm facies at ~3.1 Ma. A 3-stage tectonic model for northern PKV explains changing provenance patterns. Prior to ~3.1 Ma, the western PKV paleo-low lay north of the current GF adjacent to the southern Slate Range and connected to Searles Valley. The MGF cuts adjacent to the southern face of the Slate Range and southern Searles Valley with up to 7.5 km of sinistral oblique-normal slip between ~5-2.5 Ma. Eagle Crags fanglomerate deposition may continue after 3.7 Ma west of the Randsburg Wash-Searles Valley spillway, but these rocks have been eroded away. By ~3.7 Ma, northward progradation of Eagle Crags fanglomerate waned and lacustrine sediments were deposited north of the GF and east of the Randsburg Wash-Searles Valley spillway. At ~3.1 Ma

  6. Geochemistry of Selected Coal Samples from Sumatra, Kalimantan, Sulawesi, and Papua, Indonesia

    USGS Publications Warehouse

    Belkin, Harvey E.; Tewalt, Susan J.

    2007-01-01

    Introduction Indonesia is an archipelago of more than 17,000 islands that stretches astride the equator for about 5,200 km in southeast Asia (figure 1) and includes major Cenozoic volcano-plutonic arcs, active volcanoes, and various related onshore and offshore basins. These magmatic arcs have extensive Cu and Au mineralization that has generated much exploration and mining in the last 50 years. Although Au and Ag have been mined in Indonesia for over 1000 years (van Leeuwen, 1994), it was not until the middle of the nineteenth century that the Dutch explored and developed major Sn and minor Au, Ag, Ni, bauxite, and coal resources. The metallogeny of Indonesia includes Au-rich porphyry Cu, porphyry Mo, skarn Cu-Au, sedimentary-rock hosted Au, epithermal Au, laterite Ni, and diamond deposits. For example, the Grasberg deposit in Papua has the world's largest gold reserves and the third-largest copper reserves (Sillitoe, 1994). Coal mining in Indonesia also has had a long history beginning with the initial production in 1849 in the Mahakam coal field near Pengaron, East Kalimantan; in 1891 in the Ombilin area, Sumatra, (van Leeuwen, 1994); and in South Sumatra in 1919 at the Bukit Asam mine (Soehandojo, 1989). Total production from deposits in Sumatra and Kalimantan, from the 19thth century to World War II, amounted to 40 million metric tons (Mt). After World War II, production declined due to various factors including politics and a boom in the world-wide oil economy. Active exploration and increased mining began again in the 1980's mainly through a change in Indonesian government policy of collaboration with foreign companies and the global oil crises (Prijono, 1989). This recent coal revival (van Leeuwen, 1994) has lead Indonesia to become the largest exporter of thermal (steam) coal and the second largest combined thermal and metallurgical (coking) coal exporter in the world market (Fairhead and others, 2006). The exported coal is desirable as it is low sulfur

  7. Imaging the SE Caribbean Accretionary Boundary: Results from the BOLIVAR Seismic Reflection and Refraction data at 65W

    NASA Astrophysics Data System (ADS)

    Magnani, M.; Zelt, C. A.; Sawyer, D.; Levander, A.

    2005-12-01

    We describe a N-S, ~550 km long onshore-offshore profile at approximately 65oW., which is one of the principal seismic reflection and refraction transects acquired in 2004 as part of the Broadband Ocean and Land Investigation of Venezuela and the Antilles arc Region (BOLIVAR) experiment. Goals of BOLIVAR are to understand the complex history of the progressive oblique collision between the Leeward Antilles arc and South America that has taken place since the late Cretaceous, and to unravel the mechanisms responsible for continental growth of the South American continent through arc accretion. The transect starts ~330 km offshore northern Venezuela, in the Venezuela Basin, crosses the South America/Caribbean incipient subduction zone, the Los Roques canyon, the ABC ridge, the Tuy-Cariaco Trough (bounded by the El Pilar-Moron dextral strike-slip system), and crosses the coast east of Barcelona, Ve., continues south 175 km through the Espino Graben, and the Eastern Venezuela Basin. Multi-channel seismic reflection data were acquired by the R/V Ewing along the offshore portion of the profile, while 7 ocean bottoms seismometers (offshore) and 485 Reftek Texans (onland) recorded the Ewing airgun shots. In addition two large land shots (600 kg and 1000 kg of pentanol) were recorded by the land stations, providing reversed refraction coverage. The profile is located in a unique position along the South America/Caribbean plate boundary as it lies astride a transfer zone between the Southern Caribbean Deformed Belt, where the Caribbean plate is subducting beneath South America, and the eastern Venezuela strike-slip boundary and modern Antilles volcanic arc, where the South American plate subducts beneath the Caribbean. The structure and motion across this apparent transfer zone are unknown. The seismic data show that this area is characterized by a basement high, with little sediment coverage and velocities as high as 6.5-6.7 km/s at a depth of 8-10 km. North of the coast

  8. Precipitation-runoff processes in the Feather River basin, northeastern California, and streamflow predictability, water years 1971-97

    USGS Publications Warehouse

    Koczot, Kathryn M.; Jeton, Anne E.; McGurk, Bruce; Dettinger, Michael D.

    2005-01-01

    Precipitation-runoff processes in the Feather River Basin of northern California determine short- and long-term streamflow variations that are of considerable local, State, and Federal concern. The river is an important source of water and power for the region. The basin forms the headwaters of the California State Water Project. Lake Oroville, at the outlet of the basin, plays an important role in flood management, water quality, and the health of fisheries as far downstream as the Sacramento-San Joaquin Delta. Existing models of the river simulate streamflow in hourly, daily, weekly, and seasonal time steps, but cannot adequately describe responses to climate and land-use variations in the basin. New spatially detailed precipitation-runoff models of the basin have been developed to simulate responses to climate and land-use variations at a higher spatial resolution than was available previously. This report characterizes daily rainfall, snowpack evolution, runoff, water and energy balances, and streamflow variations from, and within, the basin above Lake Oroville. The new model's ability to predict streamflow is assessed. The Feather River Basin sits astride geologic, topographic, and climatic divides that establish a hydrologic character that is relatively unusual among the basins of the Sierra Nevada. It straddles a north-south geologic transition in the Sierra Nevada between the granitic bedrock that underlies and forms most of the central and southern Sierra Nevada and volcanic bedrock that underlies the northernmost parts of the range (and basin). Because volcanic bedrock generally is more permeable than granitic, the northern, volcanic parts of the basin contribute larger fractions of ground-water flow to streams than do the southern, granitic parts of the basin. The Sierra Nevada topographic divide forms a high altitude ridgeline running northwest to southeast through the middle of the basin. The topography east of this ridgeline is more like the rain

  9. Partners in Chemical Education: Proceedings of the International Conference on Industry - Education Initiatives in Chemistry edited by J. N. Lazonby and D. J. Waddington

    NASA Astrophysics Data System (ADS)

    Harris, Hal

    1997-06-01

    What is the place of industrial chemistry in the curriculum? Since virtually every kind of chemistry is used to produce commercial products, what is the difference between industrial and any other type? Most of the chemists that we educate will work in one of the chemical industries, and the nonmajors in our classes also should understand some of the practical chemistry that makes possible the world in which they live. The chemical industry would like to be respected (or at least not feared) for its essential role in modern societies. All of these threads met at a conference at University of York, whose proceedings were recently published. Every even-numbered year, the IUPAC sponsors a big International Conference on Chemical Education that encompasses the whole gamut of issues and developments in the field. The conference of which this volume is the Proceedings occurred in late summer, 1995, an off year for the big conference, and was designed to attract a smaller audience to a more specific topic. Given the current interest from both the academic and industrial sides of the subject of joint efforts, it is not surprising that the organizers at University of York were able to attract a sizable number of participants and a page full of industrial donors to what appears to have been a very successful five-day meeting. The Proceedings are organized into Plenary Lectures, Symposia, Workshops, and Poster Papers, but the conference itself included displays, industrial visits, informal events, and other activities that could not be captured on paper. The Plenary Lectures included contributions from both the industry and academic speakers, as well as three lectures describing Chemistry and Industry Centers, which are enhanced science museums that emphasize the role of the chemical industry. Joost Douma and Astrid van de Graaf (Prototyping for the 21st Century) described plans for such an enterprise (IMPULS), to open in April 1997 in Amsterdam. T. M. Alagiri Swamy Raju

  10. Using Digital Topography to Differentiate Erosionally Exhumed and Tectonically Active Mountains Fronts

    NASA Astrophysics Data System (ADS)

    Frankel, K. L.; Pazzaglia, F. J.

    2003-12-01

    Mountain ranges in the southern Rocky Mountains have departed on unique landscape evolutionary pathways in the late Cenozoic that are directly dependent upon the degree of post-orogenic tectonic activity they have experienced. The topography of Sierra Nacimiento, a Laramide uplift in west-central New Mexico lacking an active range-front fault, is shaped primarily by erosional exhumation that is continuous, but not steady, being driven by distal base level fall from Rio Grande incision and resultant south to north knickpoint migration. In contrast, the topography of the Taos Range, a rift flank uplift in north-central New Mexico is shaped by contrasting active stream incision and aggradation astride an active range front normal fault. The distinction between exhumation-dominated and tectonically-dominated mountain fronts is best quantified by analyses of a new metric we call the drainage basin volume to drainage basin area ratio (V-A ratio) as well as the gradients of first-order streams. Drainage basin volume and area are calculated by constructing topographic envelope maps from 10 m resolution digital elevation models (DEM). The envelope maps are pinned by the watershed divide and cover the maximum elevations in each drainage basin. Subtracting the original DEM from the maximum elevation envelope map produces a topographic residual map from which area and volume data can be obtained. The erosionally exhumed Sierra Nacimiento has a mean V-A ratio of 88 m while the tectonically active Taos Range has a mean V-A ratio of 140 m. Similarly, there are systematic differences in the gradients of first order streams measured both in the range block and approximately 5 km of adjacent piedmont. Streams were defined and subsequently Strahler ordered by a flow accumulation threshold of 250 water-equivalent grid cell units. First order stream channel long profiles were extracted from the DEM at 30 meter increments and gradients were calculated by a FORTRAN program. Gradients of

  11. Earthquake precursors in the ionosphere: electrical linkage provided by the fundamental physics of gravitation

    NASA Astrophysics Data System (ADS)

    Osmaston, Miles

    2013-04-01

    For more than a decade, evidence has been mounting that major earthquakes may be preceded, days to weeks later, by the appearance of local changes in electron density-gradient in the Earth's ionosphere above that area. Such linkage, albeit co-seismic, has been observed even when the earthquake was deep below electrically conducting seawater [1]. This appears to rule out many of the kinds of linkage that have been proposed. My inquiry as to the nature of the physical mechanism by which gravitational force is developed has led me to the surprising finding that the Newtonian potential is inevitably always accompanied by a corresponding positive-body-repelling radial electric field. I have called this the Gravity-Electric (G-E) field and have adduced evidence for its action at many astronomical scales [2 -4]. After outlining the reasoning that has led me to this result I will refer to observations which suggest that the G-E field is indeed the precursor link that we seek. Time permitting, I will show briefly how the likelihood of an ionospheric precursor will, in this case, depend on the plate dynamical mechanism and nature of the pre-quake deformation. Historical background. Newton's work on gravitation astride the end of the 17th century concentrated on the behaviour of the force, not upon its origin.. But he already endorsed the idea of an ubiquitously intervening aether tp convey the force and, as Huygens had already reasoned, also to transmit light waves. Then, in the 1860s, people [5, 6] started to think of fundamental particles as being aether in a vortex-like motion which would, by mutual attraction, provide their mass property and gravitation. In such a set-up, particles and the aether around them would not be dynamically independent, so the Michelson-Morley experiment, 20 years later [7], could equally have been interpreted as supporting that situation, not as disproving the existence of the aether. But, in setting up Relativity (1905-1916), Einstein took the

  12. PREFACE: A Stellar Journey A Stellar Journey

    NASA Astrophysics Data System (ADS)

    Asplund, M.

    2008-10-01

    appreciated non-astronomical session on Tuesday afternoon; Sigbritt Ernald provided a rich source of suggestions for suitable interesting persons to invite for the stimulating and highly enjoyable oral and musical presentations. While the responsibilities of the SOC are quite pleasant and frankly not particularly demanding, the heavy burden with organizing a conference falls squarely with the Local Organizing Committee, which has to deal with a seemingly never-ending stream of practicalities and more mundane chores. The main reason the Stellar Journey conference was such an astounding success and ran so smoothly is the tireless work by the whole LOC. All of us owe a great deal of gratitude to Paul Barklem, Nils Bergvall, Norbert Christlieb, Bengt Edvardsson (Chair), Kjell Eriksson, Ulrike Heiter, Susanne Höfner, Andreas Korn, Nikolai Piskunov, Bertrand Plez and Astrid Wachter for their extensive efforts. I'd like to also extend a special acknowledgement to all of the Uppsala students who helped out during the reception, registration and various sessions. Last but not the least, I'd like to thank all of the conference participants for giving such excellent talks and for providing stimulating discussions throughout the week. It is telling that essentially everyone invited to participate in the conference almost immediately accepted while the very few who declined did so only reluctantly due to other prior commitments. Bengt is a highly regarded colleague and friend, whom we all wished to celebrate this special occasion with. This conference represented merely one brief stop on a marvellous and truly stellar journey. I dare say that without exception we are all deeply thankful for having been able to join Bengt Gustafsson on at least some of his many cosmic adventures during the past decades. We trust that this exciting odyssey will continue for many years.

  13. Two Parent Magmas for the Same Anorthosite Pluton? The Egersund-Ogna Case

    NASA Astrophysics Data System (ADS)

    Duchesne, J.; Charlier, B.; Vander Auwera, J.

    2009-05-01

    plagioclase mainly reflect the pressure effect on the plag/melt DCaO and DSr rather than fractionation processes. (7) The LM most primitive assemblage can have crystallized at 11-13 kbar in a high-alumina basalt similar to the HLCA melt (Fram & Longhi, 1992 Am. Miner. 77, 605-616). (8) It has been suggested (Longhi et al., 1999 op. cit.) that the AA parent magma was generally similar to a primitive jotunite but slightly less evolved. However, the extended range of Cr contents in HAOM (up to 2200 ppm) and the high mg# provided by the new data are more compatible with a high-alumina basalt similar to HLCA. (9) Thus AA and LM parent magmas are high-alumina basalts similar in mg#, different in Cr and Mn, and quite distinct in Sr and Ca contents. (10) We concur with the former conclusion that both magmas have wollastonite content lower than other basaltic rocks and lie astride the thermal maximum on the opx+cpx+plag liquidus boundary. This requires melting of plag-bearing mafic sources yielding melts different in Sr, Ca, Cr and Mn contents. (11) The intrusion emplaced in two pulses. The first magma (LM) started crystallizing at depth (Al-rich HAOM) and intruded a magma chamber at intermediate depth (HAOM with intermediate Al contents) where it produced a plagioclase mush, which eventually intruded the final magma chamber. A second magma (AA) also started crystallizing HAOM and plagioclase megacrysts at depth and continued to crystallize HAOM and plagioclase en route to the final chamber (range of Al contents in HAOM). The AA diapir followed the same conduit as the first one and intruded the LM magma chamber to deform it by ballooning. The Egersund-Ogna massif is thus a nested-diapir.

  14. MEMOS - Mars Environment Monitoring Satellite

    NASA Astrophysics Data System (ADS)

    Ott, T.; Barabash, S.; von Schéele, F.; Clacey, E.; Pokrupa, N.

    2007-08-01

    ElectroMechanical Systems MEMS, Micro- Opto-ElectroMechanical Systems MOEMS and new materials to achieve low mass at high performance. Thereby it will profit from Swedish developments and heritage in small- / microsatellites like Astrid-2, SMART-1 or the upcoming rendezvous and formation flying demonstration mission PRISMA.

  15. Earthquake precursors in the ionosphere: electrical linkage provided by the fundamental physics of gravitation

    NASA Astrophysics Data System (ADS)

    Osmaston, Miles

    2013-04-01

    For more than a decade, evidence has been mounting that major earthquakes may be preceded, days to weeks later, by the appearance of local changes in electron density-gradient in the Earth's ionosphere above that area. Such linkage, albeit co-seismic, has been observed even when the earthquake was deep below electrically conducting seawater [1]. This appears to rule out many of the kinds of linkage that have been proposed. My inquiry as to the nature of the physical mechanism by which gravitational force is developed has led me to the surprising finding that the Newtonian potential is inevitably always accompanied by a corresponding positive-body-repelling radial electric field. I have called this the Gravity-Electric (G-E) field and have adduced evidence for its action at many astronomical scales [2 -4]. After outlining the reasoning that has led me to this result I will refer to observations which suggest that the G-E field is indeed the precursor link that we seek. Time permitting, I will show briefly how the likelihood of an ionospheric precursor will, in this case, depend on the plate dynamical mechanism and nature of the pre-quake deformation. Historical background. Newton's work on gravitation astride the end of the 17th century concentrated on the behaviour of the force, not upon its origin.. But he already endorsed the idea of an ubiquitously intervening aether tp convey the force and, as Huygens had already reasoned, also to transmit light waves. Then, in the 1860s, people [5, 6] started to think of fundamental particles as being aether in a vortex-like motion which would, by mutual attraction, provide their mass property and gravitation. In such a set-up, particles and the aether around them would not be dynamically independent, so the Michelson-Morley experiment, 20 years later [7], could equally have been interpreted as supporting that situation, not as disproving the existence of the aether. But, in setting up Relativity (1905-1916), Einstein took the