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Sample records for field estudio regional

  1. Magnetic Field Strengths in Photodissociation Regions

    NASA Astrophysics Data System (ADS)

    Balser, Dana S.; Anish Roshi, D.; Jeyakumar, S.; Bania, T. M.; Montet, Benjamin T.; Shitanishi, J. A.

    2016-01-01

    We measure carbon radio recombination line (RRL) emission at 5.3 {{GHz}} toward four H ii regions with the Green Bank Telescope to determine the magnetic field strength in the photodissociation region (PDR) that surrounds the ionized gas. Roshi suggests that the non-thermal line widths of carbon RRLs from PDRs are predominantly due to magneto-hydrodynamic waves, thus allowing the magnetic field strength to be derived. We model the PDR with a simple geometry and perform the non-LTE radiative transfer of the carbon RRL emission to solve for the PDR physical properties. Using the PDR mass density from these models and the carbon RRL non-thermal line width we estimate total magnetic field strengths of B∼ 100{--}300 μ {{G}} in W3 and NGC 6334A. Our results for W49 and NGC 6334D are less well constrained with total magnetic field strengths between B∼ 200{--}1000 μ {{G}}. H i and OH Zeeman measurements of the line of sight magnetic field strength ({B}{{los}}), taken from the literature, are between a factor of ∼ 0.5{--}1 of the lower bound of our carbon RRL magnetic field strength estimates. Since | {B}{{los}}| ≤slant B, our results are consistent with the magnetic origin of the non-thermal component of carbon RRL widths.

  2. Vector Magnetic Field in Emerging Flux Regions

    NASA Astrophysics Data System (ADS)

    Schmieder, B.; Pariat, E.

    A crucial phase in magnetic flux emergence is the rise of magnetic flux tubes through the solar photosphere, which represents a severe transition between the very different environments of the solar interior and corona. Multi-wavelength observations with Flare Genesis, TRACE, SoHO, and more recently with the vector magnetographs at THEMIS and Hida (DST) led to the following conclusions. The fragmented magnetic field in the emergence region - with dipped field lines or bald patches - is directly related with Ellerman bombs, arch filament systems, and overlying coronal loops. Measurements of vector magnetic fields have given evidence that undulating "serpentine" fields are present while magnetic flux tubes cross the photosphere. See the sketch below, and for more detail see Pariat et al. (2004, 2007); Watanabe et al. (2008):

  3. Geopotential field anomalies and regional tectonic features

    NASA Astrophysics Data System (ADS)

    Mandea, Mioara; Korte, Monika

    2016-07-01

    Maps of both gravity and magnetic field anomalies offer crucial information about physical properties of the Earth's crust and upper mantle, required in understanding geological settings and tectonic structures. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Two regions are considered: southern Africa (encompassing South Africa, Namibia and Botswana) and Germany. This twofold choice is motivated firstly by the fact that these regions represent rather diverse geological and geophysical conditions (old Archean crust with strong magnetic anomalies in southern Africa, and much younger, weakly magnetized crust in central Europe) and secondly by our intimate knowledge of the magnetic vector ground data from these two regions. We take also advantage of the recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of some 200 km resolution. Comparing short and long wavelength anomalies and the correlation of rather large scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement over the southern African region than the German territory. This probably indicates a stronger concordance between near-surface and deeper structures in the former area, which can be perceived to agree with a thicker lithosphere.

  4. Focal region fields of distorted reflectors

    NASA Technical Reports Server (NTRS)

    Buris, N. E.; Kauffman, J. F.

    1988-01-01

    The problem of the focal region fields scattered by an arbitrary surface reflector under uniform plane wave illumination is solved. The physical optics (PO) approximation is used to calculate the current induced on the reflector. The surface of the reflector is described by a number of triangular domain-wise 5th degree bivariate polynomials. A 2-dimensional Gaussian quadrature is employed to numerically evaluate the integral expressions of the scattered fields. No Freshnel or Fraunhofer zone approximations are made. The relation of the focal fields problem to surface compensation techniques and other applications are mentioned. Several examples of distorted parabolic reflectors are presented. The computer code developed is included, together with instructions on its usage.

  5. PFI-ZEKE (Pulsed Field Ionization-Zero Electron Kinetic Energy) para el estudio de iones

    NASA Astrophysics Data System (ADS)

    Castaño, F.; Fernández, J. A.; Basterretxea, A. Longarte. F.; Sánchez Rayo, M. N.; Martínez, R.

    Entre las áreas hacia donde ha evolucionado la Química en los últimos años están los estudios de sistemas con especies reactivas de alta energía y los dominados por fuerzas intermoleculares débiles, con energías de unas pocas kcal/mol. En efecto, el estudio de las propiedades de los iones, comenzando por su relación con la molécula neutra de la que procede, la energía de ionización, los estados vibracionales y rotacionales, energías de enlace de Van der Waals entre el ión y una amplia variedad de otras moléculas, sus confórmeros o isómeros y sus reacciones o semi-reacciones químicas están en la raíz de la necesidad de la espectroscopía conocida como PFI-ZEKE, Pulsed Field Ionization-Zero Electron Kinetic Energy. Entre las aplicaciones que requieren estos conocimientos se encuentran la generación de plasmas para la fabricación de semiconductores, memorias magnéticas, etc, así como los sistemas astrofísicos, la ionosfera terrestre, etc. La espectroscopía ZEKE es una evolución de las de fluorescencia inducida por láser, LIF, ionización multifotónica acrecentada por resonancia, REMPI, con uno y dos colores y acoplada a un sistema de tiempo de vuelo, REMPI-TOF-MS, y las espectroscopías de doble resonancia IR-UV y UV-UV. Sus espectros y la ayuda de cálculos ab inicio permite determinar las energías de enlace de complejos de van der Waals en estados fundamental y excitados, identificar confórmeros e isómeros, obtener energías de ionización experimentales aproximadas (100 cm-1) y otras variables de interés. Al igual que con LIF, REMPI y dobles resonancias, es posible utilizar muestras gaseosas, pero los espectros están muy saturados de bandas y su interpretación es difícil o imposible. Se evitan estas dificultades estudiando las moléculas o complejos en expansiones supersónicas, donde la T de los grados de libertad solo alcanzan unos pocos K. Para realizar experimentos de ZEKE hay que utilizar una propiedad recientemente

  6. The Life Cycle of Active Region Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Cheung, M. C. M.; van Driel-Gesztelyi, L.; Martínez Pillet, V.; Thompson, M. J.

    2016-08-01

    We present a contemporary view of how solar active region magnetic fields are understood to be generated, transported and dispersed. Empirical trends of active region properties that guide model development are discussed. Physical principles considered important for active region evolution are introduced and advances in modeling are reviewed.

  7. Differential Magnetic Field Shear in an Active Region

    NASA Technical Reports Server (NTRS)

    Schmeider, B.; DeMoulin, P.; Aulanier, G.; Golub, Leon

    1997-01-01

    The three-dimensional extrapolation of magnetic field lines from a magnetogram obtained at Kitt Peak allows us to understand the global structure of the NOAA active region 6718, as observed in X-rays with the Normal Incidence X-ray Telescope (NIXT) and in Ha with the Multichannel Subtractive Double Pass spectrograph (MSDP) in Meudon on 1991 July 11. This active region was in a quiet stage. Bright X-ray loops connect plages having field strengths of approx. 300 G, while H-alpha fibriles connect penumbrae having strong spot fields to the surrounding network. Small, intense X-ray features in the moat region around a large spot, which could be called X-ray-bright points, are due mainly to the emergence of magnetic flux and merging of these fields with surrounding ones. A set of large-scale, sheared X-ray loops is observed in the central part of the active region. Based on the fit between the observed coronal structure and the field configurations (and assuming a linear force-free field), we propose a differential magnetic field shear model for this active region. The decreasing shear in outer portions of the active region may indicate a continual relaxation of the magnetic field to a lower energy state in the progressively older portions of the AR.

  8. Wake Fields in the Super B Factory Interaction Region

    SciTech Connect

    Weathersby, Stephen; Novokhatski, Alexander; /SLAC

    2011-06-02

    The geometry of storage ring collider interaction regions present an impedance to beam fields resulting in the generation of additional electromagnetic fields (higher order modes or wake fields) which affect the beam energy and trajectory. These affects are computed for the Super B interaction region by evaluating longitudinal loss factors and averaged transverse kicks for short range wake fields. Results indicate at least a factor of 2 lower wake field power generation in comparison with the interaction region geometry of the PEP-II B-factory collider. Wake field reduction is a consderation in the Super B design. Transverse kicks are consistent with an attractive potential from the crotch nearest the beam trajectory. The longitudinal loss factor scales as the -2.5 power of the bunch length. A factor of 60 loss factor reduction is possible with crotch geometry based on an intersecting tubes model.

  9. Formation of active region and quiescent prominence magnetic field configurations

    NASA Technical Reports Server (NTRS)

    An, C.-H.; Bao, J. J.; Wu, S. T.

    1986-01-01

    To investigate the formation of prominences, researchers studied chromospheric mass injection into an overlying coronal dipole magnetic field using a 2-D ideal magnetohydrodynamic (MHD) numerical model. Researchers propose that active region prominences are formed by chromospheric plasmas injected directly into the overlying coronal magnetic field and that quiescent prominences are formed by plasmas evaporated at the interface between spicules and corona. Hence, for the simulation of an active region prominence magnetic field we inject the mass from one side, but use a symmetric mass injection to form a quiescent prominence field configuration. Researchers try to find optimum conditions for the formation of Kippenhahn-Schuluter(K-S)type field configuration for stable support of the injection plasmas. They find that the formation of K-S type field configuration by mass injection requires a delicate balance between injection velocity, density, and overlying magnetic fields. These results may explain why a prominence does not form on every neutral line.

  10. Estudios interferométricos del campo magnético en regiones de formación estelar

    NASA Astrophysics Data System (ADS)

    Fernández López, M.; Stephens, I.; Segura-Cox, D.; Crutcher, R.; Looney, L. W.; Kwon, W.

    2015-08-01

    Currently, the possible role of magnetic fields in star formation processes is not clear. Despite the efforts made through single-dish observations, a stronger observational effort is required in order to broaden the sample of detections and acquire more insight into the morphology of the magnetic field at high-angular resolution scales. Here we present some results obtained from CARMA 1.25 mm continuum and spectral line polarization observations. The target of these observations were two accretion disks around a Class 0 (L1527) and a T Tauri (HL Tau) protostar and the massive star-forming region W3OH. We resolved the morphology of the magnetic field in both disks and, in W3OH, we achieved the first Zeeman detection ever made with an interferometer.

  11. The coronal field lines of an evolving bipolar magnetic region

    NASA Technical Reports Server (NTRS)

    Sheeley, N. R., Jr.

    1982-01-01

    A simple potential field model is presented to illustrate that loops of magnetic flux rise upward through the corona during the relatively short growth phase of a bipolar magnetic region but contract back to the sun's surface during the much longer decay phase of the photospheric region. To reconcile this behavior with the unidirectional, solar-wind-driven convection of flux outward from the sun, one must postulate the existence of an X-type neutral line in the middle corona where open field lines can be converted back to closed ones.

  12. Relationship between Birkeland current regions, particle precipitation, and electric fields

    NASA Technical Reports Server (NTRS)

    De La Beaujardiere, O.; Watermann, J.; Newell, P.; Rich, F.

    1993-01-01

    The relationship of the large-scale dayside Birkeland currents to large-scale particle precipitation patterns, currents, and convection is examined using DMSP and Sondrestrom radar observations. It is found that the local time of the mantle currents is not limited to the longitude of the cusp proper, but covers a larger local time extent. The mantle currents flow entirely on open field lines. About half of region 1 currents flow on open field lines, consistent with the assumption that the region 1 currents are generated by the solar wind dynamo and flow within the surface that separates open and closed field lines. More than 80 percent of the Birkeland current boundaries do not correspond to particle precipitation boundaries. Region 2 currents extend beyond the plasma sheet poleward boundary; region 1 currents flow in part on open field lines; mantle currents and mantle particles are not coincident. On most passes when a triple current sheet is observed, the convection reversal is located on closed field lines.

  13. ABRUPT LONGITUDINAL MAGNETIC FIELD CHANGES IN FLARING ACTIVE REGIONS

    SciTech Connect

    Petrie, G. J. D.; Sudol, J. J.

    2010-12-01

    We characterize the changes in the longitudinal photospheric magnetic field during 38 X-class and 39 M-class flares within 65{sup 0} of disk center using 1 minute GONG magnetograms. In all 77 cases, we identify at least one site in the flaring active region where clear, permanent, stepwise field changes occurred. The median duration of the field changes was about 15 minutes and was approximately equal for X-class and for M-class flares. The absolute values of the field changes ranged from the detection limit of {approx}10 G to as high as {approx}450 G in two exceptional cases. The median value was 69 G. Field changes were significantly stronger for X-class than for M-class flares and for limb flares than for disk-center flares. Longitudinal field changes less than 100 G tended to decrease longitudinal field strengths, both close to disk center and close to the limb, while field changes greater than 100 G showed no such pattern. Likewise, longitudinal flux strengths tended to decrease during flares. Flux changes, particularly net flux changes near disk center, correlated better than local field changes with GOES peak X-ray flux. The strongest longitudinal field and flux changes occurred in flares observed close to the limb. We estimate the change of Lorentz force associated with each flare and find that this is large enough in some cases to power seismic waves. We find that longitudinal field decreases would likely outnumber increases at all parts of the solar disk within 65{sup 0} of disk center, as in our observations, if photospheric field tilts increase during flares as predicted by Hudson et al.

  14. Chromospheric magnetic fields of an active region filament

    NASA Astrophysics Data System (ADS)

    Xu, Z.; Solanki, S.; Lagg, A.

    2012-06-01

    Vector magnetic fields of an active region filament are co-spatially and co-temporally mapped in photosphere and upper chromosphere, by using spectro-polarimetric observations made by Tenerife Infrared Polarimeter (TIP II) at the German Vacuum Tower Telescope (VTT). A Zeeman-based ME inversion is performed on the full Stokes vectors of both the photospheric Si I 1082.7 nm and the chromospheric He I 1083.0 nm lines. We found that the strong magnetic fields, with the field strength of 600 - 800 G in the He I line formation height, are not uncommon among AR filaments. But such strong magnetic field is not always found in AR filaments.

  15. Quasistatic electric field structures and field-aligned currents in the polar cusp region

    NASA Astrophysics Data System (ADS)

    Jacobsen, K. S.; Moen, J. I.; Pedersen, A.

    2010-10-01

    Cluster data have been examined for quasi-stationary electric field structures and field-aligned currents (FACs) in the vicinity of the dayside cusp region. We have related the measurements to the Region 1/Region 2 (R1/R2) current system and the cusp current system. It has been theoretically proposed that the dayside R1 current may be located on open field lines, and experimental evidence has been shown for R1 currents partially on open field lines. We document that R1 currents may flow entirely on open field lines. The electric field structures are found to occur at plasma density gradients in the cusp. They are associated with strong FACs with current directions that are consistent with the cusp currents. This indicates that the electric field structures are closely coupled to the cusp current system. The electric equipotential structures linking the perpendicular electric fields seen at Cluster altitudes to field-aligned electric fields at lower altitudes fall into one of two categories: S shape or U shape. Both types are found at both the equatorward edge of the cusp ion dispersion and at the equatorward edge of injection events within the cusp. Previous studies in the nightside auroral region attributed the S-shaped potential structures to the boundary transition between the low-density polar cap and the high-density plasma sheet, concluding that the shape of the electric potential structure depends on whether the plasma populations on each side of the structure can support intense currents. This explanation is not applicable for the S-shaped structures observed in the dayside cusp region.

  16. Active Region Filaments Might Harbor Weak Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Díaz Baso, C. J.; Martínez González, M. J.; Asensio Ramos, A.

    2016-05-01

    Recent spectropolarimetric observations of active region filaments have revealed polarization profiles with signatures typical of the strong field Zeeman regime. The conspicuous absence in those observations of scattering polarization and Hanle effect signatures was then pointed out by some authors. This was interpreted as either a signature of mixed “turbulent” field components or as a result of optical thickness. In this article, we present a natural scenario to explain these Zeeman-only spectropolarimetric observations of active region (AR) filaments. We propose a two-component model, one on top of the other. Both components have horizontal fields, with the azimuth difference between them being close to 90°. The component that lies lower in the atmosphere is permeated by a strong field of the order of 600 G, while the upper component has much weaker fields, of the order of 10 G. The ensuing scattering polarization signatures of the individual components have opposite signs, so its combination along the line of sight reduces—and even can cancel out—the Hanle signatures, giving rise to an apparent Zeeman-only profile. This model is also applicable to other chromospheric structures seen in absorption above ARs.

  17. Chiral Effective Field Theory in the $\\Delta$-resonance region

    SciTech Connect

    Vladimir Pascalutsa

    2006-09-18

    I discuss the problem of constructing an effective low-energy theory in the vicinity of a resonance or a bound state. The focus is on the example of the $\\Delta(1232)$, the lightest resonance in the nucleon sector. Recent developments of the chiral effective-field theory in the $\\Delta$-resonance region are briefly reviewed. I conclude with a comment on the merits of the manifestly covariant formulation of chiral EFT in the baryon sector.

  18. Automated detection of open magnetic field regions in EUV images

    NASA Astrophysics Data System (ADS)

    Krista, Larisza Diana; Reinard, Alysha

    2016-05-01

    Open magnetic regions on the Sun are either long-lived (coronal holes) or transient (dimmings) in nature, but both appear as dark regions in EUV images. For this reason their detection can be done in a similar way. As coronal holes are often large and long-lived in comparison to dimmings, their detection is more straightforward. The Coronal Hole Automated Recognition and Monitoring (CHARM) algorithm detects coronal holes using EUV images and a magnetogram. The EUV images are used to identify dark regions, and the magnetogam allows us to determine if the dark region is unipolar – a characteristic of coronal holes. There is no temporal sensitivity in this process, since coronal hole lifetimes span days to months. Dimming regions, however, emerge and disappear within hours. Hence, the time and location of a dimming emergence need to be known to successfully identify them and distinguish them from regular coronal holes. Currently, the Coronal Dimming Tracker (CoDiT) algorithm is semi-automated – it requires the dimming emergence time and location as an input. With those inputs we can identify the dimming and track it through its lifetime. CoDIT has also been developed to allow the tracking of dimmings that split or merge – a typical feature of dimmings.The advantage of these particular algorithms is their ability to adapt to detecting different types of open field regions. For coronal hole detection, each full-disk solar image is processed individually to determine a threshold for the image, hence, we are not limited to a single pre-determined threshold. For dimming regions we also allow individual thresholds for each dimming, as they can differ substantially. This flexibility is necessary for a subjective analysis of the studied regions. These algorithms were developed with the goal to allow us better understand the processes that give rise to eruptive and non-eruptive open field regions. We aim to study how these regions evolve over time and what environmental

  19. Intraplate Stress Field in Brazil Using Focal Mechanisms: Regional and Local Patterns: Examples of Regional Forces Controlling the Stress Field

    NASA Astrophysics Data System (ADS)

    Dias, F. L.; Assumpcao, M.

    2014-12-01

    The knowledge of stress field is fundamental not only to understand driving forces and plate deformation but also in the study of intraplate seismicity. In Brazil, the stress field has been determined mainly using focal mechanisms and a breakout data and in-situ measurements. However, the stress field still is poorly known in Brazil. We show a recent compilation of focal mechanism determined in Brazil (Fig 1). The focal mechanisms of some recent earthquakes (magnitude lower than 5 mb) were studied using waveform modeling. We stacked the record of several teleseismic stations (> 30°) with a good signal/noise ratio and we grouped then according to distance and azimuth. With the focal mechanisms available in literature and those obtained in this work, we were able to identify some patterns: the central region shows compressional pattern (E-W SHmax), which is predicted by regional theoretical models ( Coblentz & Richardson, 1996 and the TD0 model of Lithgow & Bertelloni, 2004). This compression is mainly due to the interaction of tectonic plate forces. Meanwhile in the Amazon region, we find an indication of SHMax oriented in the SE-NW direction, probably caused by the Caribbean plate interaction (Meijer, 1995) and Amazon Fan, we have flexural stresses caused by sedimentary load with is in agreement with local theoretical models (Watts et al., 2009) . In northern coastal region, the compression rotates following the coastline, which indicates an important local component related to spreading effects at the continental/oceanic transition (Assumpção, 1998). We determine the focal mechanism of several events in Brazil using different techniques according to the available data. The major difficulty is to determine focal mechanism of low magnitudes events (< 5.0 mb) using distant or few seismograph stations. We find examples of stress perturbations induced by local effects (e.g. flexure and continental spreading). The results of this work should be useful for future

  20. Dynamic nuclear polarization in the hyperfine-field-dominant region

    NASA Astrophysics Data System (ADS)

    Lee, Seong-Joo; Shim, Jeong Hyun; Kim, Kiwoong; Yu, Kwon Kyu; Hwang, Seong-min

    2015-06-01

    Dynamic nuclear polarization (DNP) allows measuring enhanced nuclear magnetic resonance (NMR) signals. Though the efficiency of DNP has been known to increase at low fields, the usefulness of DNP has not been throughly investigated yet. Here, using a superconducting quantum interference device-based NMR system, we performed a series of DNP experiments with a nitroxide radical and measured DNP spectra at several magnetic fields down to sub-microtesla. In the DNP spectra, the large overlap of two peaks having opposite signs results in net enhancement factors, which are significantly lower than theoretical expectations [30] and nearly invariant with respect to magnetic fields below the Earth's field. The numerical analysis based on the radical's Hamiltonian provides qualitative explanations of such features. The net enhancement factor reached 325 at maximum experimentally, but our analysis reveals that the local enhancement factor at the center of the rf coil is 575, which is unaffected by detection schemes. We conclude that DNP in the hyperfine-field-dominant region yields sufficiently enhanced NMR signals at magnetic fields above 1 μ T.

  1. Measuring Magnetic Fields in Photoionized Interstellar Plasmas (HII Regions)

    NASA Astrophysics Data System (ADS)

    Spangler, Steven; Costa, Allison

    2015-11-01

    Hot luminous stars photoionize the interstellar gas around them, creating plasmas with a very high ionization fraction. In astronomical terminology, these are called HII regions. They are dynamic plasmas, expanding due to overpressure with respect to the interstellar medium. We are making diagnostic measurements to determine the strength and structure of magnetic fields in these objects. This paper presents our results on the Rosette Nebula. We diagnose the magnetic field in the Rosette by measurements of Faraday rotation on lines of sight passing through the nebula. These measurements are made with the Very Large Array radio telescope of the National Radio Astronomy Observatory. We have measurements of the rotation measure for 18 lines of sight. Values of the mean, line of sight component of the magnetic field range from about 3 to 5 microGauss. We will discuss comparison of these measurements with models for modification of the interstellar magnetic field by an HII region. This work was supported by grants AST09-07911 and ATM09-56901 from the National Science Foundation.

  2. Regional and local geologic structure of the Momotombo field, Nicaragua

    SciTech Connect

    Goldsmith, L.H.

    1980-09-01

    The regional geologic-tectonic setting of northwestern Nicaragua is the result of subduction. Differential plate margin movement and segmentation formed a deep rift paralleling the Middle American Trench. Deep-seated shear faults provided access to sublithospheric magmas to create the Nicaraguan volcanic chain. Volcan Momotombo is the southernmost volcano of the Marabios Range of northern Nicaragua. It hosts a proven geothermal resource known as the Momotombo field, located within a small graben structure and measuring less than one square kilometer. This geothermally productive area appears not to be a geothermal reservoir, but rather part of a thermal convection system. Wells in the central and eastern part of the field have diminished in output and temperature. The presence of a temperature inversion zone, clearly distinguishable in the eastern end of the field, indicates that no conductive heating of the productive zone is taking place.

  3. Model of macroeconomic evolution in stable regionally dependent economic fields

    NASA Astrophysics Data System (ADS)

    Ausloos, M.; Clippe, P.; Pekalski, A.

    2004-06-01

    We develop a model for the evolution of economic entities within a geographical type of framework. On a square symmetry lattice made of three (economic) regions, firms, described by a scalar fitness, are allowed to move, adapt, merge or create spin-offs under predetermined rules, in a space- and time-dependent economic environment. We only consider here one timely variation of the “external economic field condition”. For the firm fitness evolution, we take into account a constraint such that the disappearance of a firm modifies the fitness of nearest-neighboring ones, as in Bak-Sneppen population fitness evolution model. The concentration of firms, the averaged fitness, the regional distribution of firms, and fitness for different time moments, the number of collapsed, merged and new firms as a function of time have been recorded and are discussed. Also the asymptotic values of the number of firms present in the three regions together with their average fitness, as well as the number of respective births and collapses in the three regions are examined. It appears that a sort of critical selection pressure exists. A power-law dependence, signature of self-critical organization is seen in the birth and collapse asymptotic values for a high selection pressure only. A lack of self-organization is also seen at region borders.

  4. Magnetic fields in star-forming regions - Observations

    NASA Technical Reports Server (NTRS)

    Heiles, Carl; Goodman, Alyssa A.; Mckee, Christopher F.; Zweibel, Ellen G.

    1993-01-01

    We review the observational aspects of magnetic fields in dense, star-forming regions. First we discuss ways to observe the field. These include direct methods, which consist of the measurement of both linear and circular polarization of spectral line and continuum radiation; and indirect methods, consisting of the angular distribution of H2O masers on the sky and the measurement of ambipolar diffusion. Next we discuss selected observational results, focusing on detailed discussions of a small number of points rather than a generalized discussion that covers the waterfront. We discuss the Orion/BN-KL region in detail, both on the small and large scales. Next we discuss the derivation of the complete magnetic vector, including both the systematic and fluctuating component, from a large sample of Zeeman and linear polarization measurements for the L204 dark cloud. We examine the virial theorem as it applies to dark clouds in general and one dark cloud, Barnard 1, in particular. We critically discuss the numerous claims for alignment of cloud structural features with the plane-of-the-sky component of the magnetic field, and find that many of these have not been definitively established.

  5. Videomagnetograph studies of solar magnetic fields. II - Field changes in an active region

    NASA Technical Reports Server (NTRS)

    Schoolman, S. A.

    1973-01-01

    Using the Caltech videomagnetograph, we obtained a 6.5-hr movie of the magnetic fields in a young active region. The major contribution to the short term magnetic evolution of the region was provided by many discrete magnetic points which move in apparently random directions with typical velocities of 0.4 - 1.0 km/sec. The majority of these features appear to be footpoints of new EFR's, which emerge at an observed rate of one to two per hour. The pattern of the motions suggests that the magnetic evolution of a growing region cannot be principally due to photospheric convective cells.

  6. Fine structure of the magnetic field in active regions

    NASA Astrophysics Data System (ADS)

    Pustilnik, Lev; Beskrovnaya, Nina; Ikhsanov, Nazar

    High-resolution observations with SOHO, SDO, TRACE, HINODE suggest that the solar magnetic field in active regions has a complicated fine structure. There is a large number of thin magnetic arcs extended from the photosphere to corona with almost constant cross-section. We explore a possibility to model the complex of interacting arcs in terms of a dynamical percolating network. A transition of the system into flaring can be triggered by the flute instability of prominences and/or coronal condensations. We speculate around an assumption that the energy release in active regions is governed by the same scenario as dynamical current percolation through a random resistors network in which the saltatory conduction is controlled by a local current level.

  7. Two-field high-scale inflation in a sub-Planckian region of field space

    SciTech Connect

    Berg, Marcus; Pajer, Enrico; Sjoers, Stefan

    2010-05-15

    We present a simple two-field model of inflation and show how to embed it in string theory as a straightforward generalization of axion monodromy models. Phenomenologically, the predictions are equivalent to those of chaotic inflation, and, in particular, include observably large tensor modes. The whole high-scale large-field inflationary dynamics takes place within a region of field space that is parametrically sub-Planckian in diameter, hence improving our ability to control quantum corrections and achieve slow-roll inflation.

  8. Plasma Equilibrium in a Magnetic Field with Stochastic Regions

    SciTech Connect

    J.A. Krommes and Allan H. Reiman

    2009-04-23

    The nature of plasma equilibrium in a magnetic field with stochastic regions is examined. It is shown that the magnetic differential equation that determines the equilibrium Pfirsch-Schluter currents can be cast in a form similar to various nonlinear equations for a turbulent plasma, allowing application of the mathematical methods of statistical turbulence theory. An analytically tractable model, previously studied in the context of resonance-broadening theory, is applied with particular attention paid to the periodicity constraints required in toroidal configurations. It is shown that even a very weak radial diffusion of the magnetic field lines can have a significant effect on the equilibrium in the neighborhood of the rational surfaces, strongly modifying the near-resonant Pfirsch-Schluter currents. Implications for the numerical calculation of 3D equilibria are discussed

  9. Analysis of supersonic combustion flow fields with embedded subsonic regions

    NASA Technical Reports Server (NTRS)

    Dash, S.; Delguidice, P.

    1972-01-01

    The viscous characteristic analysis for supersonic chemically reacting flows was extended to include provisions for analyzing embedded subsonic regions. The numerical method developed to analyze this mixed subsonic-supersonic flow fields is described. The boundary conditions are discussed related to the supersonic-subsonic and subsonic-supersonic transition, as well as a heuristic description of several other numerical schemes for analyzing this problem. An analysis of shock waves generated either by pressure mismatch between the injected fluid and surrounding flow or by chemical heat release is also described.

  10. Quasistatic electric field structures and field-aligned currents in the polar cusp region

    NASA Astrophysics Data System (ADS)

    Jacobsen, Knut; Moen, Joran; Pedersen, Arne

    2010-05-01

    Quasistatic electric field structures in the vicinity of the cusp have been studied using Cluster data. There are two categories of electric potential structures, S-shaped and U-shaped. In previous studies in the nightside auroral region, the S-shaped potential was uniquely related to the boundary transition between low density and high density plasma regimes, leading to the conclusion that the electric field profile depends on whether the plasma populations on each side of the boundary can support intense field-aligned and Pedersen currents. In this study in the dayside cusp this is not the case, and a different explanation has to be sought. Most electric field structures are associated with the start of the cusp ion dispersion or with injection signatures within the cusp, and the field-aligned currents associated with these structures are found to be consistent with the cusp currents expected for the IMF By polarity at the time. This indicates that the electric field structures are generated by the cusp current system, or modified by the cusp current system to be consistent with the required currents. Furthermore, we provide firm evidence for the dayside Region 1 current to be located on open field lines, which have been postulated but to our knowledge heretofore not experimentally verified.

  11. Adiabatic theory in regions of strong field gradients. [in magnetosphere

    NASA Technical Reports Server (NTRS)

    Whipple, E. C.; Northrop, T. G.; Birmingham, T. J.

    1986-01-01

    The theory for the generalized first invariant for adiabatic motion of charged particles in regions where there are large gradients in magnetic or electric fields is developed. The general condition for an invariant to exist in such regions is that the potential well in which the particle oscillates change its shape slowly as the particle drifts. It is shown how the Kruskal (1962) procedure can be applied to obtain expressions for the invariant and for drift velocities that are asymptotic in a smallness parameter epsilon. The procedure is illustrated by obtaining the invariant and drift velocities for particles traversing a perpendicular shock, and the generalized invariant is compared with the magnetic moment, and the drift orbits with the actual orbits, for a particular case. In contrast to the magnetic moment, the generalized first invariant is better for large gyroradii (large kinetic energies) than for small gyroradii. Expressions for the invariant when an electrostatic potential jump is imposed across the perpendicular shock, and when the particle traverses a rotational shear layer with a small normal component of the magnetic field are given.

  12. Quantifying solar superactive regions with vector magnetic field observations

    NASA Astrophysics Data System (ADS)

    Chen, A. Q.; Wang, J. X.

    2012-07-01

    Context. The vector magnetic field characteristics of superactive regions (SARs) hold the key for understanding why SARs are extremely active and provide the guidance in space weather prediction. Aims: We aim to quantify the characteristics of SARs using the vector magnetograms taken by the Solar Magnetic Field Telescope at Huairou Solar Observatory Station. Methods: The vector magnetic field characteristics of 14 SARs in solar cycles 22 and 23 were analyzed using the following four parameters: 1) the magnetic flux imbalance between opposite polarities; 2) the total photospheric free magnetic energy; 3) the length of the magnetic neutral line with its steep horizontal magnetic gradient; and 4) the area with strong magnetic shear. Furthermore, we selected another eight large and inactive active regions (ARs), which are called fallow ARs (FARs), to compare them with the SARs. Results: We found that most of the SARs have a net magnetic flux higher than 7.0 × 1021 Mx, a total photospheric free magnetic energy higher than 1.0 × 1024 erg cm-1, a magnetic neutral line with a steep horizontal magnetic gradient (≥300 G Mm-1) longer than 30 Mm, and an area with strong magnetic shear (shear angle ≥ 80°) greater than 100 Mm2. In contrast, the values of these parameters for the FARs are mostly very low. The Pearson χ2 test was used to examine the significance of the difference between the SARs and FARs, and the results indicate that these two types of ARs can be fairly distinguished by each of these parameters. The significance levels are 99.55%, 99.98%, 99.98%, and 99.96%, respectively. However, no single parameter can distinguish them perfectly. Therefore we propose a composite index based on these parameters, and find that the distinction between the two types of ARs is also significant with a significance level of 99.96%. These results are useful for a better physical understanding of the SAR and FAR.

  13. An analysis of the flow field in the region of the ASRM field joints

    NASA Technical Reports Server (NTRS)

    Dill, Richard A.; Whitesides, Harold R.

    1992-01-01

    The flow field in the region of a solid rocket motor field joint is very important since fluid dynamic and mechanical propellant stresses can couple to cause a motor failure at a joint. Presented here is an examination of the flow field in the region of the Advanced Solid Rocket Motor (ASRM) field joints. The analyses were performed as a first step in assessing the design of the ASRM forward and aft field joints in order to assure the proper operation of the motor prior to further development of test firing. The analyses presented here were performed by employing a two-dimensional axisymmetric assumption. Fluent/BFC, a three dimensional full Navier-Stokes flow field code, was used to make the numerical calculations. This code utilizes a staggered grid formulation along with the SIMPLER numerical algorithm. Wall functions are used to determine the character of the laminar sublayer, and a standard kappa-epsilon turbulence model is used to close the fluid dynamic equations. The analyses performed to this date verify that the ASRM field joint design operates properly. The fluid dynamic stresses at the field joints are small due to the inherent design of the field joints. A problem observed in some other solid rocket motors is that large fluid dynamic stresses are generated at the motor joint on the downstream propellant grain due to forward facing step geometries. The design of the ASRM field joints are such that this is not a problem as shown by the analyses. Also, the analyses of the inhibitor stub left protruding into the port flow from normal propellant burn back show that more information is necessary to complete these analyses. These analyses were performed as parametric analyses in relation to the height of the inhibitor stub left protruding into the motor port. A better estimate of the amount of the inhibitor stub remaining at later burn times must be determined since the height which the inhibitor stub protrudes into the port flow drastically affects the fluid

  14. An analysis of the flow field in the region of the ASRM field joints

    NASA Astrophysics Data System (ADS)

    Dill, Richard A.; Whitesides, Harold R.

    1992-07-01

    The flow field in the region of a solid rocket motor field joint is very important since fluid dynamic and mechanical propellant stresses can couple to cause a motor failure at a joint. Presented here is an examination of the flow field in the region of the Advanced Solid Rocket Motor (ASRM) field joints. The analyses were performed as a first step in assessing the design of the ASRM forward and aft field joints in order to assure the proper operation of the motor prior to further development of test firing. The analyses presented here were performed by employing a two-dimensional axisymmetric assumption. Fluent/BFC, a three dimensional full Navier-Stokes flow field code, was used to make the numerical calculations. This code utilizes a staggered grid formulation along with the SIMPLER numerical algorithm. Wall functions are used to determine the character of the laminar sublayer, and a standard kappa-epsilon turbulence model is used to close the fluid dynamic equations. The analyses performed to this date verify that the ASRM field joint design operates properly. The fluid dynamic stresses at the field joints are small due to the inherent design of the field joints. A problem observed in some other solid rocket motors is that large fluid dynamic stresses are generated at the motor joint on the downstream propellant grain due to forward facing step geometries. The design of the ASRM field joints are such that this is not a problem as shown by the analyses. Also, the analyses of the inhibitor stub left protruding into the port flow from normal propellant burn back show that more information is necessary to complete these analyses. These analyses were performed as parametric analyses in relation to the height of the inhibitor stub left protruding into the motor port. A better estimate of the amount of the inhibitor stub remaining at later burn times must be determined since the height which the inhibitor stub protrudes into the port flow drastically affects the fluid

  15. Magnetic field measurements in and above a limb active region

    NASA Astrophysics Data System (ADS)

    Philip, Judge

    2013-07-01

    We analyze spectropolarimetric data of a limb active region (NOAA 11302) obtained on September 22nd 2011 using the Facility Infrared Spectrometer (FIRS) at the Dunn Solar Telescope (DST). Stokes profiles including lines of Si I 1028.7 nm and He I 1083 nm were obtained in three scans over a 45"x75" area. Simultaneous narrow band Ca II K and G-band intensity data were acquired with a cadence of 5s at the DST. The He I data show not only typical active region polarization signatures, but also signatures in plumes -- cool post flare loops -- which extend many Mm into the corona across the visible limb. The plumes have remarkably uniform brightness, and the plume plasma is significantly Doppler shifted as it drains from the corona. Using carefully constructed observing and calibration sequences and applying Principal Component Analysis to remove instrumental artifacts, we achieved a polarization sensitivity approaching 0.02%. With this sensitivity we attempt to diagnose the vector magnetic fields and plasma properties of chromospheric and cool coronal material in and above NOAA 11302. Inversions using various radiative transfer models in the HAZEL code are remarkably consistent with the idea that plume spectra are formed in a simple, slab-like geometry, but that the ``disk'' spectra are formed under more traditional models (Milne-Eddington). The inverted magnetic data of He I lines are compared with photospheric inversions of DST Si I and Fe I data from the Solar Dynamics Observatory.

  16. Generation and Suppression of E Region Artificial Field Aligned Irregularities

    NASA Astrophysics Data System (ADS)

    Miceli, R. J.; Hysell, D. L.; Munk, J.; Han, S.

    2012-12-01

    Artificial field-aligned plasma density irregularities (FAIs) were generated in the E region of the ionosphere above the High Frequency Active Auroral Research Program (HAARP) facility during campaigns in May and August of 2012 and were quantified using a 30 MHz coherent scatter radar in Homer, Alaska. The purpose of the experiment was to analyze the X-mode suppression of FAIs generated from O-mode heating and to measure the threshold required to excite thermal parametric instabilities. The irregularities were excited by gradually increasing the power of a zenith pointing O-mode emission transmitted at a frequency of 2.75 MHz. To suppress the irregularities, a second X-mode emission at a higher frequency was added on alternating power cycles. The Homer radar measured the signal-to-noise ratio, Doppler shift, and spectral width of echoes reflected from the irregularities. We will calculate the threshold electric field required to excite the irregularities and compare with similar experiments in order to better understand the thermal parametric instability.

  17. The effects of magnetic field in plume region on the performance of multi-cusped field thruster

    SciTech Connect

    Hu, Peng Liu, Hui Yu, Daren; Gao, Yuanyuan; Mao, Wei

    2015-10-15

    The performance characteristics of a Multi-cusped Field Thruster depending on the magnetic field in the plume region were investigated. Five magnetic field shielding rings were separately mounted near the exit of discharge channel to decrease the strength of magnetic field in the plume region in different levels, while the magnetic field in the upstream was well maintained. The test results show that the electron current increases with the decrease of magnetic field strength in the plume region, which gives rise to higher propellant utilization and lower current utilization. On the other hand, the stronger magnetic field in the plume region improves the performance at low voltages (high current mode) while lower magnetic field improves the performance at high voltages (low current mode). This work can provide some optimal design ideas of the magnetic strength in the plume region to improve the performance of thruster.

  18. Forecasting auroras from regional and global magnetic field measurements

    NASA Astrophysics Data System (ADS)

    Kauristie, Kirsti; Myllys, Minna; Partamies, Noora; Viljanen, Ari; Peitso, Pyry; Juusola, Liisa; Ahmadzai, Shabana; Singh, Vikramjit; Keil, Ralf; Martinez, Unai; Luginin, Alexej; Glover, Alexi; Navarro, Vicente; Raita, Tero

    2016-06-01

    We use the connection between auroral sightings and rapid geomagnetic field variations in a concept for a Regional Auroral Forecast (RAF) service. The service is based on statistical relationships between near-real-time alerts issued by the NOAA Space Weather Prediction Center and magnetic time derivative (dB/dt) values measured by five MIRACLE magnetometer stations located in Finland at auroral and sub-auroral latitudes. Our database contains NOAA alerts and dB/dt observations from the years 2002-2012. These data are used to create a set of conditional probabilities, which tell the service user when the probability of seeing auroras exceeds the average conditions in Fennoscandia during the coming 0-12 h. Favourable conditions for auroral displays are associated with ground magnetic field time derivative values (dB/dt) exceeding certain latitude-dependent threshold values. Our statistical analyses reveal that the probabilities of recording dB/dt exceeding the thresholds stay below 50 % after NOAA alerts on X-ray bursts or on energetic particle flux enhancements. Therefore, those alerts are not very useful for auroral forecasts if we want to keep the number of false alarms low. However, NOAA alerts on global geomagnetic storms (characterized with Kp values > 4) enable probability estimates of > 50 % with lead times of 3-12 h. RAF forecasts thus rely heavily on the well-known fact that bright auroras appear during geomagnetic storms. The additional new piece of information which RAF brings to the previous picture is the knowledge on typical storm durations at different latitudes. For example, the service users south of the Arctic Circle will learn that after a NOAA ALTK06 issuance in night, auroral spotting should be done within 12 h after the alert, while at higher latitudes conditions can remain favourable during the next night.

  19. Wide Field Imaging of the Hubble Deep Field-South Region III: Catalog

    NASA Technical Reports Server (NTRS)

    Palunas, Povilas; Collins, Nicholas R.; Gardner, Jonathan P.; Hill, Robert S.; Malumuth, Eliot M.; Rhodes, Jason; Teplitz, Harry I.; Woodgate, Bruce E.

    2002-01-01

    We present 1/2 square degree uBVRI imaging around the Hubble Deep Field - South. These data have been used in earlier papers to examine the QSO population and the evolution of the correlation function in the region around the HDF-S. The images were obtained with the Big Throughput Camera at CTIO in September 1998. The images reach 5 sigma limits of u approx. 24.4, B approx. 25.6, V approx. 25.3, R approx. 24.9 and I approx. 23.9. We present a catalog of approx. 22,000 galaxies. We also present number-magnitude counts and a comparison with other observations of the same field. The data presented here are available over the world wide web.

  20. Regional Ecorisk Field investigation, upper Clark Fork River Basin

    SciTech Connect

    Pastorok, R.; LaTier, A.; Ginn, T.

    1995-12-31

    The Regional Ecorisk Field Investigation was conducted at the Clark Fork River Superfund Site (Montana) to evaluate the relationships between plant communities and tailings deposits in riparian habitats and to evaluate food-chain transfer of trace elements to selected wildlife species. Stations were selected to represent a range of vegetation biomass (or cover) values and apparent impact of trace elements, with some areas of lush vegetation, some areas of mostly unvegetated soil (e.g., < 30 percent plant cover), and a gradient in between. For the evaluation of risk to wildlife, bioaccumulation of metals was evaluated in native or naturalized plants, terrestrial invertebrates, and the deer mouse (Peromyscus maniculatus). Potential reproductive effects in the deer mouse were evaluated by direct measurements. For other wildlife species, bioaccumulation data were interpreted in the context of food web exposure models. Total biomass and species richness of riparian plant communities are related to tailings content of soil as indicated by pH and metals concentrations. Risk to populations of omnivorous small mammals such as the deer mouse was not significant. Relative abundance and reproductive condition of the deer mouse were normal, even in areas of high metals enrichment. Based on exposure models and site-specific tissue residue data for dietary species, risk to local populations of predators such as red fox and American kestrel that feed on deer mice and terrestrial invertebrates is not significant. Risk to herbivores related to metals bioaccumulation in plant tissues is not significant. Population level effects in deer and other large wildlife are not expected because of the large home ranges of such species and compensatory demographic factors.

  1. Regional assemblages of Lygus (Heteroptera: Miridae) in Montana canola fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sweep net sampling of canola (Brassica napus L.) was conducted in 2002 and 2003 to determine Lygus (Heteroptera: Miridae) species composition and parasitism levels in four regions of Montana. Regardless of region or seasonal change, Lygus elisus (Van Duzee) was the dominant species in all canola fi...

  2. The identification and interaction of network, intranetwork, and ephemeral-region magnetic fields

    NASA Technical Reports Server (NTRS)

    Martin, Sara F.

    1988-01-01

    Network magnetic fields are described as the dynamic product of the merging and cancelling of intranetwork fields, ephemeral regions, and the remnants of active regions. The similarities of these phenomena with solar magnetic features are pointed out. The intranetwork magnetic fields are characterized by the flow of successive fragments in approximately radial patterns away from their apparent source sites.

  3. Mapping Magnetic Fields in Star Forming Regions with BLASTPol

    NASA Astrophysics Data System (ADS)

    Fissel, Laura M.; Ade, Peter; Angilè, Francesco E.; Ashton, Peter; Benton, Steven J.; Devlin, Mark J.; Dober, Bradley; Fukui, Yasuo; Galitzki, Nicholas B.; Gandilo, Natalie; Klein, J. R.; Li, Zhi-Yun; Korotkov, Andrei; Martin, Peter G.; Matthews, Tristan; Moncelsi, Lorenzo; nakamura, fumitaka; Barth Netterfield, Calvin; Novak, Giles; Pascale, Enzo; Poidevin, Frédérick; Pereira Santos, Fábio; Savini, Giorgio; Scott, Douglas; Shariff, Jamil; Soler, Juan D.; Thomas, Nicholas; tucker, carole; Tucker, Gregory S.; Ward-Thompson, Derek

    2016-01-01

    A key outstanding question in our understanding of star formation is whether magnetic fields provide support against the gravitational collapse of their parent molecular clouds and cores. Direct measurement of magnetic field strength is observationally challenging, however observations of polarized thermal emission from dust grains aligned with respect to the local cloud magnetic field can be used to map out the magnetic field orientation in molecular clouds. Statistical comparisons between these submillimeter polarization maps and three-dimensional numerical simulations of magnetized star-forming clouds provide a promising method for constraining magnetic field strength. We present early results from a BLASTPol study of the nearby giant molecular cloud (GMC) Vela C, using data collected during a 2012 Antarctic flight. This sensitive balloon-borne polarimeter observed Vela C for 57 hours, yielding the most detailed submillimeter polarization map ever made of a GMC forming high mass stars. We find that most of the structure in p can be modeled by a power-law dependence on two quantities: the hydrogen column density and the local dispersion in magnetic field orientation. Our power-law model for p(N,S) provides new constraints for models of magnetized star-forming clouds and an important first step in the interpretation of the BLASTPol 2012 data set.

  4. Correlation between magnetic and electric field perturbations in the field-aligned current regions deduced from DE 2 observations

    NASA Technical Reports Server (NTRS)

    Ishii, M.; Sugiura, M.; Iyemori, T.; Slavin, J. A.

    1992-01-01

    The satellite-observed high correlations between magnetic and electric field perturbations in the high-latitude field-aligned current regions are investigated by examining the dependence of the relationship between Delta-B and E on spatial scale, using the electric and magnetic field data obtained by DE 2 in the polar regions. The results are compared with the Pedersen conductivity inferred from the international reference ionosphere model and the Alfven wave velocity calculated from the in situ ion density and magnetic field measurements.

  5. [Selected medical closed claims in the field of regional anaesthesia].

    PubMed

    Kessler, Paul; Schaffartzik, Walter; Neu, Johann

    2016-05-01

    Legal malpractice cases in regional anaesthesia comprise a significant number of all cases before the expert commissions and arbitration boards of the state medical associations. One reason for this is the increasing use of neuraxial and peripheral regional blocks in orthopaedics and traumatology. Only in about one fourth of the reviewed cases could either a causal relationship between substandard performance and patient injury or an inadequate obtaining of informed consent be established. In the great majority of cases patients' claims were unfounded, since the patients' injuries were adjudged to be unavoidable and adequate consent had been abtained prior to performance of the blocks. PMID:27213606

  6. Optical singularities and power flux in the near-field region of planar evanescent-field superlenses.

    PubMed

    Perez-Molina, Manuel; Carretero, L; Acebal, P; Blaya, S

    2008-11-01

    We rigorously analyze the optical singularities and power flux in the near-field region of the novel superlenses reported in [Science317, 927 (2007)] For this purpose, we derive near-field expressions and a general criterion to classify the optical singularities in the vacuum, which are valid when the (s- or p-polarized) electromagnetic fields are generated by any planar field distribution with Cartesian or azimuthal symmetry. Such general results are particularized to the superlenses [Science317, 927 (2007)], for which we identify a sequence of optical vortices and saddles that arise from evanescent-field interference. While the saddles are always located around the focal region, the vortex locations depend on the source field. The features of the topological connection between vortices and saddles are also discussed. PMID:18978868

  7. 5 CFR Appendix II to Part 1201 - Appropriate Regional or Field Office for Filing Appeals

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Appropriate Regional or Field Office for Filing Appeals II Appendix II to Part 1201 Administrative Personnel MERIT SYSTEMS PROTECTION BOARD ORGANIZATION AND PROCEDURES PRACTICES AND PROCEDURES Pt. 1201, App. II Appendix II to Part 1201—Appropriate Regional or Field Office for Filing...

  8. Laboratory study of diffusion region with electron energization during high guide field reconnection

    NASA Astrophysics Data System (ADS)

    Yamasaki, K.; Inoue, S.; Kamio, S.; Watanabe, T. G.; Ushiki, T.; Guo, X.; Sugawara, T.; Matsuyama, K.; Kawakami, N.; Yamada, T.; Inomoto, M.; Ono, Y.

    2015-10-01

    Floating potential profile was measured around the X-point during high guide field reconnection in UTST merging experiment where the ratio of guide field ( Bg ) to reconnecting magnetic field ( Brec ) is Bg/Brec>10 . Floating potential measurement revealed that a quadrupole structure of electric potential is formed around the X-point during the fast reconnection phase due to the polarization by inductive electric field. Also, our floating potential measurement revealed the existence of parallel electric field in the vicinity of the X-point. While field-aligned components of inductive electric field ( E∥ind ) and electrostatic electric field ( E∥es ) cancel out with each other away from the X-point, E∥ind exceeds E∥es around the X-point, indicating the deviation from ideal MHD criterion within the region. The diffusion region extends in the outflow region and the scale length of region is an order of ion skin depth, which is quite different from the VTF experiment result. Based on the measured magnetic field and electric field profile, our particle trajectory analysis indicates that fast electrons with energies over 300 eV are produced within 1 μs around the X-point in the non-ideal MHD region. These results indicate that production of fast electrons or electron heating are expected to be observed in the vicinity of the X-point.

  9. H II REGION DRIVEN GALACTIC BUBBLES AND THEIR RELATIONSHIP TO THE GALACTIC MAGNETIC FIELD

    SciTech Connect

    Pavel, Michael D.; Clemens, D. P. E-mail: clemens@bu.edu

    2012-12-01

    The relative alignments of mid-infrared traced Galactic bubbles are compared to the orientation of the mean Galactic magnetic field in the disk. The orientations of bubbles in the northern Galactic plane were measured and are consistent with random orientations-no preferential alignment with respect to the Galactic disk was found. A subsample of H II region driven Galactic bubbles was identified, and as a single population they show random orientations. When this subsample was further divided into subthermal and suprathermal H II regions, based on hydrogen radio recombination linewidths, the subthermal H II regions showed a marginal deviation from random orientations, but the suprathermal H II regions showed significant alignment with the Galactic plane. The mean orientation of the Galactic disk magnetic field was characterized using new near-infrared starlight polarimetry and the suprathermal H II regions were found to preferentially align with the disk magnetic field. If suprathermal linewidths are associated with younger H II regions, then the evolution of young H II regions is significantly affected by the Galactic magnetic field. As H II regions age, they cease to be strongly linked to the Galactic magnetic field, as surrounding density variations come to dominate their morphological evolution. From the new observations, the ratios of magnetic-to-ram pressures in the expanding ionization fronts were estimated for younger H II regions.

  10. Scaling up from field to region for wind erosion prediction using a field-scale wind erosion model and GIS

    USGS Publications Warehouse

    Zobeck, T.M.; Parker, N.C.; Haskell, S.; Guoding, K.

    2000-01-01

    Factors that affect wind erosion such as surface vegetative and other cover, soil properties and surface roughness usually change spatially and temporally at the field-scale to produce important field-scale variations in wind erosion. Accurate estimation of wind erosion when scaling up from fields to regions, while maintaining meaningful field-scale process details, remains a challenge. The objectives of this study were to evaluate the feasibility of using a field-scale wind erosion model with a geographic information system (GIS) to scale up to regional levels and to quantify the differences in wind erosion estimates produced by different scales of soil mapping used as a data layer in the model. A GIS was used in combination with the revised wind erosion equation (RWEQ), a field-scale wind erosion model, to estimate wind erosion for two 50 km2 areas. Landsat Thematic Mapper satellite imagery from 1993 with 30 m resolution was used as a base map. The GIS database layers included land use, soils, and other features such as roads. The major land use was agricultural fields. Data on 1993 crop management for selected fields of each crop type were collected from local government agency offices and used to 'train' the computer to classify land areas by crop and type of irrigation (agroecosystem) using commercially available software. The land area of the agricultural land uses was overestimated by 6.5% in one region (Lubbock County, TX, USA) and underestimated by about 21% in an adjacent region (Terry County, TX, USA). The total estimated wind erosion potential for Terry County was about four times that estimated for adjacent Lubbock County. The difference in potential erosion among the counties was attributed to regional differences in surface soil texture. In a comparison of different soil map scales in Terry County, the generalised soil map had over 20% more of the land area and over 15% greater erosion potential in loamy sand soils than did the detailed soil map. As

  11. Capturing field-scale variability in crop performance across a regional-scale climosequence

    NASA Astrophysics Data System (ADS)

    Brooks, E. S.; Poggio, M.; Anderson, T. R.; Gasch, C.; Yourek, M. A.; Ward, N. K.; Magney, T. S.; Brown, D. J.; Huggins, D. R.

    2014-12-01

    With the increasing availability of variable rate technology for applying fertilizers and other agrichemicals in dryland agricultural production systems there is a growing need to better capture and understand the processes driving field scale variability in crop yield and soil water. This need for a better understanding of field scale variability has led to the recent designation of the R. J. Cook Agronomy Farm (CAF) (Pullman, WA, USA) as a United States Department of Agriculture Long-Term Agro-Ecosystem Research (LTAR) site. Field scale variability at the CAF is closely monitored using extensive environmental sensor networks and intensive hand sampling. As investigating land-soil-water dynamics at CAF is essential for improving precision agriculture, transferring this knowledge across the regional-scale climosequence is challenging. In this study we describe the hydropedologic functioning of the CAF in relation to five extensively instrumented field sites located within 50 km in the same climatic region. The formation of restrictive argillic soil horizons in the wetter, cooler eastern edge of the region results in the development of extensive perched water tables, surface saturation, and surface runoff, whereas excess water is not an issue in the warmer, drier, western edge of the region. Similarly, crop and tillage management varies across the region as well. We discuss the implications of these regional differences on field scale management decisions and demonstrate how we are using proximal soil sensing and remote sensing imagery to better understand and capture field scale variability at a particular field site.

  12. Spatial distributions of magnetic field in the RHIC and LHC energy regions

    NASA Astrophysics Data System (ADS)

    Zhong, Yang; Yang, Chun-Bin; Cai, Xu; Feng, Sheng-Qin

    2015-10-01

    Relativistic heavy-ion collisions can produce extremely strong magnetic fields in the collision regions. The spatial variation features of the magnetic fields are analyzed in detail for non-central Pb-Pb collisions at LHC at \\sqrt{s_NN}=900, 2760 and 7000 GeV and Au-Au collisions at RHIC at \\sqrt{s_NN}=62.4, 130 and 200 GeV. The dependencies of magnetic field on proper time, collision energies and impact parameters are investigated in this paper. It is shown that an enormous and highly inhomogeneous spatial distribution magnetic field can indeed be created in off-centre relativistic heavy-ion collisions in RHIC and LHC energy regions. The enormous magnetic field is produced just after the collision, and the magnitude of magnetic field of the LHC energy region is larger than that of the RHIC energy region at small proper time. It is found that the magnetic field in the LHC energy region decreases more quickly with the increase of proper time than that of the RHIC energy region. Supported by National Natural Science Foundation of China (11375069, 11435054, 11075061, 11221504) and Key Laboratory foundation of Quark and Lepton Physics (Hua-Zhong Normal University) (QLPL2014P01)

  13. HELIOSHEATH MAGNETIC FIELDS BETWEEN 104 AND 113 AU IN A REGION OF DECLINING SPEEDS AND A STAGNATION REGION

    SciTech Connect

    Burlaga, L. F.; Ness, N. F. E-mail: nfnudel@yahoo.com

    2012-04-10

    We examine the relationships between the magnetic field and the radial velocity component V{sub R} observed in the heliosheath by instruments on Voyager 1 (V1). No increase in the magnetic field strength B was observed in a region where V{sub R} decreased linearly from 70 km s{sup -1} to 0 km s{sup -1} as plasma moved outward past V1. An unusually broad transition from positive to negative polarity was observed during a Almost-Equal-To 26 day interval when the heliospheric current sheet (HCS) moved below the latitude of V1 and the speed of V1 was comparable to the radial speed of the heliosheath flow. When V1 moved through a region where V{sub R} Almost-Equal-To 0 (the 'stagnation region'), B increased linearly with time by a factor of two, and the average of B was 0.14 nT. Nothing comparable to this was observed previously. The magnetic polarity was negative throughout the stagnation region for Almost-Equal-To 580 days until 2011 DOY 235, indicating that the HCS was below the latitude of V1. The average passage times of the magnetic holes and proton boundary layers were the same during 2009 and 2011, because the plasma moved past V1 during 2009 at the same speed that V1 moved through the stagnation region during 2011. The microscale fluctuations of B in the stagnation region during 2011 are qualitatively the same as those observed in the heliosheath during 2009. These results suggest that the stagnation region is a part of the heliosheath, rather than a 'transition region' associated with the heliopause.

  14. Regional Mapping of the Lunar Crustal Magnetic Field: Correlation of Strong Anomalies with Curvilinear Albedo Markings

    NASA Technical Reports Server (NTRS)

    Hood, L. L.; Yingst, A.; Zakharian, A.; Lin, R. P.; Mitchell, D. L.; Halekas, J.; Acuna, M. H.; Binder, A. B.

    2000-01-01

    Using high-resolution regional Lunar Prospector magnetometer magnetic field maps, we report here a close correlation of the strongest individual crustal anomalies with unusual curvilinear albedo markings of the Reiner Gamma class.

  15. On the Electron Diffusion Region in Asymmetric Reconnection with a Guide Magnetic Field

    NASA Technical Reports Server (NTRS)

    Hesse, Michael; Liu, Yi-Hsin; Chen, Li-Jen; Bessho, Naoki; Kuznetsova, Masha; Birn, Joachim; Burch, James L.

    2016-01-01

    Particle-in-cell simulations in a 2.5-D geometry and analytical theory are employed to study the electron diffusion region in asymmetric reconnection with a guide magnetic field. The analysis presented here demonstrates that similar to the case without guide field, in-plane flow stagnation and null of the in-plane magnetic field are well separated. In addition, it is shown that the electric field at the local magnetic X point is again dominated by inertial effects, whereas it remains dominated by nongyrotropic pressure effects at the in-plane flow stagnation point. A comparison between local electron Larmor radii and the magnetic gradient scale lengths predicts that distribution should become nongyrotropic in a region enveloping both field reversal and flow stagnation points. This prediction is verified by an analysis of modeled electron distributions, which show clear evidence of mixing in the critical region.

  16. Fields and Flares: Understanding the Complex Magnetic Topologies of Solar Active Regions

    NASA Astrophysics Data System (ADS)

    Murray, Sophie A.

    2013-01-01

    Sunspots are regions of decreased brightness on the visible surface of the Sun (photosphere) that are associated with strong magnetic fields. They have been found to be locations associated with solar flares, which occur when energy stored in sunspot magnetic fields is suddenly released. The processes involved in flaring and the link between sunspot magnetic fields and flares is still not fully understood, and this thesis aims to gain a better understanding of these topics. The magnetic field evolution of a number of sunspot regions is examined using high spatial resolution data from the Hinode spacecraft. The research presented in this thesis gives insight into both photospheric and coronal magnetic field evolution of flaring regions. Significant increases in vertical field strength, current density, and field inclination angle towards the vertical are observed in the photosphere just hours before a flare occurs, which is on much shorter timescales than previously studied. First observations of spatial changes in field inclination across a magnetic neutral line (generally believed to be a typical source region of flares) are also discovered. 3D magnetic field extrapolation methods are used to study the coronal magnetic field, using the photospheric magnetic field data as a boundary condition. Magnetic energy and free magnetic energy are observed to increase significantly a few hours before a flare, and decrease afterwards, which is a similar trend to the photospheric field parameter changes observed. Evidence of partial Taylor relaxation is also detected after a flare, as predicted by several previous studies. The results outlined in this thesis show that this particular field of research is vital in furthering our understanding of the magnetic nature of sunspots and its link to flare processes.

  17. A Wide-Field Survey in the Chandra Deep Field-South Region: A Combined GTO + GO Approach

    NASA Astrophysics Data System (ADS)

    Garmire, Gordon

    2013-09-01

    We propose to perform a wide-field (2.2 square degree) survey around the Chandra Deep Field-South (CDF-S) and Extended Chandra Deep Field-South (E-CDF-S). This survey will complement the large observational investments made in multi-square-degree surveys in the CDF-S region by Spitzer, Herschel, the Australia Telescope Compact Array, PRIMUS, Pan-STARRS, DES, LSST, and other facilities. It will allow us to identify the most-luminous active galaxies to z = 1.5-2 and to investigate large-scale structures in the CDF-S region. This is the GTO component of a GTO + GO project; the associated GO observations will be proposed as a Cycle 15 Large Project.

  18. Relationship between magnetic field properties and an X-class flare in active region NOAA 9077

    NASA Astrophysics Data System (ADS)

    Liu, S.; Liu, D.

    2016-04-01

    The magnetic field plays a key role in producing solar flares, so that the investigation on the relationship between the magnetic field properties and flares is significant. In this paper, based on the magnetic field extrapolated from the photospheric vector magnetograms of the active region NOAA 9077 obtained at Huairou Solar Observing Station, the magnetic field parameters including the height of field lines, force-free factor, free magnetic energy and inclination angle were studied with respect to an X-class flare in this region. We found that the magnetic field lines became lower and the ratio of number of closed field lines to those of open field lines increased after the flare. The force-free factor (α) attained a large value before the flare and then decreased after the flare for the closed field lines, while the open field lines showed the opposite tendency. Free energy reach to maximum before flare, then decrease after flare. The magnetic inclination angles showed opposite change trends after the flare for closed and open field lines. Therefore, we may conclude that non-potential energy released by flare mostly contained in the closed magnetic field lines.

  19. A region of intense plasma wave turbulence on auroral field lines

    NASA Technical Reports Server (NTRS)

    Gurnett, D. A.; Frank, L. A.

    1976-01-01

    This report presents a detailed study of the plasma wave turbulence observed by HAWKEYE-1 and IMP-6 on high latitude auroral field lines and investigates the relationship of this turbulence to magnetic field and plasma measurements obtained in the same region.

  20. How Much Energy Can Be Stored in Solar Active Region Magnetic Fields?

    NASA Astrophysics Data System (ADS)

    Linker, J.; Downs, C.; Torok, T.; Titov, V. S.; Lionello, R.; Mikic, Z.; Riley, P.

    2015-12-01

    Major solar eruptions such as X-class flares and very fast coronal mass ejections usually originate in active regions on the Sun. The energy that powers these events is believed to be stored as free magnetic energy (energy above the potential field state) prior to eruption. While coronal magnetic fields are not in general force-free, active regions have very strong magnetic fields and at low coronal heights the plasma beta is therefore very small, making the field (in equilibrium) essentially force-free. The Aly-Sturrock theorem shows that the energy of a fully force-free field cannot exceed the energy of the so-called open field. If the theorem holds, this places an upper limit on the amount of free energy that can be stored: the maximum free energy (MFE) is the difference between the open field energy and the potential field energy of the active region. In thermodynamic MHD simulations of a major eruption (the July 14, 2000 'Bastille' day event) and a modest event (February 13, 2009, we have found that the MFE indeed bounds the energy stored prior to eruption. We compute the MFE for major eruptive events in cycles 23 and 24 to investigate the maximum amount of energy that can be stored in solar active regions.Research supported by AFOSR, NASA, and NSF.

  1. Flexible gas insulated transmission line having regions of reduced electric field

    DOEpatents

    Cookson, Alan H.; Fischer, William H.; Yoon, Kue H.; Meyer, Jeffry R.

    1983-01-01

    A gas insulated transmission line having radially flexible field control means for reducing the electric field along the periphery of the inner conductor at predetermined locations wherein the support insulators are located. The radially flexible field control means of the invention includes several structural variations of the inner conductor, wherein careful controlling of the length to depth of surface depressions produces regions of reduced electric field. Several embodiments of the invention dispose a flexible connector at the predetermined location along the inner conductor where the surface depressions that control the reduced electric field are located.

  2. Regional-Scale High-Latitude Extreme Geoelectric Fields Pertaining to Geomagnetically Induced Currents

    NASA Technical Reports Server (NTRS)

    Pulkkinen, Antti; Bernabeu, Emanuel; Eichner, Jan; Viljanen, Ari; Ngwira, Chigomezyo

    2015-01-01

    Motivated by the needs of the high-voltage power transmission industry, we use data from the high-latitude IMAGE magnetometer array to study characteristics of extreme geoelectric fields at regional scales. We use 10-s resolution data for years 1993-2013, and the fields are characterized using average horizontal geoelectric field amplitudes taken over station groups that span about 500-km distance. We show that geoelectric field structures associated with localized extremes at single stations can be greatly different from structures associated with regionally uniform geoelectric fields, which are well represented by spatial averages over single stations. Visual extrapolation and rigorous extreme value analysis of spatially averaged fields indicate that the expected range for 1-in-100-year extreme events are 3-8 V/km and 3.4-7.1 V/km, respectively. The Quebec reference ground model is used in the calculations.

  3. Dose discrepancies in the buildup region and their impact on dose calculations for IMRT fields

    SciTech Connect

    Hsu, Shu-Hui; Moran, Jean M.; Chen Yu; Kulasekere, Ravi; Roberson, Peter L.

    2010-05-15

    Purpose: Dose accuracy in the buildup region for radiotherapy treatment planning suffers from challenges in both measurement and calculation. This study investigates the dosimetry in the buildup region at normal and oblique incidences for open and IMRT fields and assesses the quality of the treatment planning calculations. Methods: This study was divided into three parts. First, percent depth doses and profiles (for 5x5, 10x10, 20x20, and 30x30 cm{sup 2} field sizes at 0 deg., 45 deg., and 70 deg. incidences) were measured in the buildup region in Solid Water using an Attix parallel plate chamber and Kodak XV film, respectively. Second, the parameters in the empirical contamination (EC) term of the convolution/superposition (CVSP) calculation algorithm were fitted based on open field measurements. Finally, seven segmental head-and-neck IMRT fields were measured on a flat phantom geometry and compared to calculations using {gamma} and dose-gradient compensation (C) indices to evaluate the impact of residual discrepancies and to assess the adequacy of the contamination term for IMRT fields. Results: Local deviations between measurements and calculations for open fields were within 1% and 4% in the buildup region for normal and oblique incidences, respectively. The C index with 5%/1 mm criteria for IMRT fields ranged from 89% to 99% and from 96% to 98% at 2 mm and 10 cm depths, respectively. The quality of agreement in the buildup region for open and IMRT fields is comparable to that in nonbuildup regions. Conclusions: The added EC term in CVSP was determined to be adequate for both open and IMRT fields. Due to the dependence of calculation accuracy on (1) EC modeling, (2) internal convolution and density grid sizes, (3) implementation details in the algorithm, and (4) the accuracy of measurements used for treatment planning system commissioning, the authors recommend an evaluation of the accuracy of near-surface dose calculations as a part of treatment planning

  4. Numerical analyses of trapped field magnet and stable levitation region of HTSC

    SciTech Connect

    Tsuchimoto, M.; Kojima, T.; Waki, H.; Honma, T.

    1995-05-01

    Stable levitation with a permanent magnet and a bulk high {Tc} superconductor (HTSC) is examined numerically by using the critical state model and the frozen field model. Differences between a permanent magnet and a trapped field magnet are first discussed from property of levitation force. Stable levitation region of the HTSC on a ring magnet and on a solenoid coil are calculated with the numerical methods. Obtained results are discussed from difference of the magnetic field configuration.

  5. MODELING MAGNETIC FIELD STRUCTURE OF A SOLAR ACTIVE REGION CORONA USING NONLINEAR FORCE-FREE FIELDS IN SPHERICAL GEOMETRY

    SciTech Connect

    Guo, Y.; Ding, M. D.; Liu, Y.; Sun, X. D.; DeRosa, M. L.; Wiegelmann, T.

    2012-11-20

    We test a nonlinear force-free field (NLFFF) optimization code in spherical geometry using an analytical solution from Low and Lou. Several tests are run, ranging from idealized cases where exact vector field data are provided on all boundaries, to cases where noisy vector data are provided on only the lower boundary (approximating the solar problem). Analytical tests also show that the NLFFF code in the spherical geometry performs better than that in the Cartesian one when the field of view of the bottom boundary is large, say, 20 Degree-Sign Multiplication-Sign 20 Degree-Sign . Additionally, we apply the NLFFF model to an active region observed by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory (SDO) both before and after an M8.7 flare. For each observation time, we initialize the models using potential field source surface (PFSS) extrapolations based on either a synoptic chart or a flux-dispersal model, and compare the resulting NLFFF models. The results show that NLFFF extrapolations using the flux-dispersal model as the boundary condition have slightly lower, therefore better, force-free, and divergence-free metrics, and contain larger free magnetic energy. By comparing the extrapolated magnetic field lines with the extreme ultraviolet (EUV) observations by the Atmospheric Imaging Assembly on board SDO, we find that the NLFFF performs better than the PFSS not only for the core field of the flare productive region, but also for large EUV loops higher than 50 Mm.

  6. Convective-region geometry as the cause of Uranus' and Neptune's unusual magnetic fields.

    PubMed

    Stanley, Sabine; Bloxham, Jeremy

    2004-03-11

    The discovery of Uranus' and Neptune's non-dipolar, non-axisymmetric magnetic fields destroyed the picture--established by Earth, Jupiter and Saturn--that planetary magnetic fields are dominated by axial dipoles. Although various explanations for these unusual fields have been proposed, the cause of such field morphologies remains unexplained. Planetary magnetic fields are generated by complex fluid motions in electrically conducting regions of the planets (a process known as dynamo action), and so are intimately linked to the structure and evolution of planetary interiors. Determining why Uranus and Neptune have different field morphologies is not only critical for studying the interiors of these planets, but also essential for understanding the dynamics of magnetic-field generation in all planets. Here we present three-dimensional numerical dynamo simulations that model the dynamo source region as a convecting thin shell surrounding a stably stratified fluid interior. We show that this convective-region geometry produces magnetic fields similar in morphology to those of Uranus and Neptune. The fields are non-dipolar and non-axisymmetric, and result from a combination of the stable fluid's response to electromagnetic stress and the small length scales imposed by the thin shell. PMID:15014493

  7. MAGNETIC FIELD TOPOLOGY AND THE THERMAL STRUCTURE OF THE CORONA OVER SOLAR ACTIVE REGIONS

    SciTech Connect

    Schrijver, Carolus J.; DeRosa, Marc L.; Title, Alan M.

    2010-08-20

    Solar extreme ultraviolet (EUV) images of quiescent active-region coronae are characterized by ensembles of bright 1-2 MK loops that fan out from select locations. We investigate the conditions associated with the formation of these persistent, relatively cool, loop fans within and surrounding the otherwise 3-5 MK coronal environment by combining EUV observations of active regions made with TRACE with global source-surface potential-field models based on the full-sphere photospheric field from the assimilation of magnetograms that are obtained by the Michelson Doppler Imager (MDI) on SOHO. We find that in the selected active regions with largely potential-field configurations these fans are associated with (quasi-)separatrix layers (QSLs) within the strong-field regions of magnetic plage. Based on the empirical evidence, we argue that persistent active-region cool-loop fans are primarily related to the pronounced change in connectivity across a QSL to widely separated clusters of magnetic flux, and confirm earlier work that suggested that neither a change in loop length nor in base field strengths across such topological features are of prime importance to the formation of the cool-loop fans. We discuss the hypothesis that a change in the distribution of coronal heating with height may be involved in the phenomenon of relatively cool coronal loop fans in quiescent active regions.

  8. Effect of geometry on the nose-region flow-field of shuttle entry-configurations

    NASA Technical Reports Server (NTRS)

    Bertin, J. J.; Faria, H. T.

    1973-01-01

    In order to determine the convective heat-transfer distribution for the nose region of the space shuttle entry configurations, a three-dimensional flow-field is described which may include extensive regions of separated flow. Because of the complexity of the flow field for the nose region, experimental data are needed to define the relation between the nose geometry and the resultant flow field. According to theoretical solutions of the three-dimensional boundary layer, the boundary layer separates from the leeward generator of a blunted cone at an alpha equal to the cone half-angle. Separation results from the transverse pressure gradient, i.e., the velocity derivative due to crossflow. The boundary layer limiting streamlines converge toward the singular point of sep aration. The separated region is bounded by an ordinary line of separation.

  9. Fresnel-region fields and antenna noise-temperature calculations for advanced microwave sounding units

    NASA Technical Reports Server (NTRS)

    Schmidt, R. F.

    1982-01-01

    A transition from the antenna noise temperature formulation for extended noise sources in the far-field or Fraunhofer-region of an antenna to one of the intermediate near field or Fresnel-region is discussed. The effort is directed toward microwave antenna simulations and high-speed digital computer analysis of radiometric sounding units used to obtain water vapor and temperature profiles of the atmosphere. Fresnel-region fields are compared at various distances from the aperture. The antenna noise temperature contribution of an annular noise source is computed in the Fresnel-region (D squared/16 lambda) for a 13.2 cm diameter offset-paraboloid aperture at 60 GHz. The time-average Poynting vector is used to effect the computation.

  10. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection.

    PubMed

    Eriksson, S; Wilder, F D; Ergun, R E; Schwartz, S J; Cassak, P A; Burch, J L; Chen, L-J; Torbert, R B; Phan, T D; Lavraud, B; Goodrich, K A; Holmes, J C; Stawarz, J E; Sturner, A P; Malaspina, D M; Usanova, M E; Trattner, K J; Strangeway, R J; Russell, C T; Pollock, C J; Giles, B L; Hesse, M; Lindqvist, P-A; Drake, J F; Shay, M A; Nakamura, R; Marklund, G T

    2016-07-01

    We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E_{∥}) that is larger than predicted by simulations. The high-speed (∼300  km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E_{∥} is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure. PMID:27419573

  11. Magnetic field observations as Voyager 1 entered the heliosheath depletion region.

    PubMed

    Burlaga, L F; Ness, N F; Stone, E C

    2013-07-12

    Magnetic fields measured by Voyager 1 (V1) show that the spacecraft crossed the boundary of an unexpected region five times between days 210 and ~238 in 2012. The magnetic field strength B increased across this boundary from ≈0.2 to ≈0.4 nanotesla, and B remained near 0.4 nanotesla until at least day 270, 2012. The strong magnetic fields were associated with unusually low counting rates of >0.5 mega-electron volt per nuclear particle. The direction of B did not change significantly across any of the five boundary crossings; it was very uniform and very close to the spiral magnetic field direction, which was observed throughout the heliosheath. The observations indicate that V1 entered a region of the heliosheath (the heliosheath depletion region), rather than the interstellar medium. PMID:23811226

  12. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Eriksson, S.; Wilder, F. D.; Ergun, R. E.; Schwartz, S. J.; Cassak, P. A.; Burch, J. L.; Chen, L.-J.; Torbert, R. B.; Phan, T. D.; Lavraud, B.; Goodrich, K. A.; Holmes, J. C.; Stawarz, J. E.; Sturner, A. P.; Malaspina, D. M.; Usanova, M. E.; Trattner, K. J.; Strangeway, R. J.; Russell, C. T.; Pollock, C. J.; Giles, B. L.; Hesse, M.; Lindqvist, P.-A.; Drake, J. F.; Shay, M. A.; Nakamura, R.; Marklund, G. T.

    2016-07-01

    We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E∥ ) that is larger than predicted by simulations. The high-speed (˜300 km /s ) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E∥ is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.

  13. Analysis of Possible Magnetic Field Configurations of Mercury In Response To The Impinging Solar Wind: Open Field Regions and Magnetosheath Plasma Access Into The Inner Regions.

    NASA Astrophysics Data System (ADS)

    Massetti, S.; Orsini, S.; Milillo, A.; Mura, A.; de Angelis, E.

    The presence of a magnetosphere around Mercury plays a fundamental role on the way the solar wind plasma interacts with the planet. In particular, the relative weakness of the magnetic field compared with the size of Mercury, together with the absence of an atmosphere, leads to relevant differences between the physical phenomena acting on Earth and Mercury. On the basis of a modified Tsyganenko T96 model we try to figure out the geometry of the magnetic field that could characterise Mercury, and its response to the variations of the impinging solar wind. The investigation is focused on the shape and dimension of the open field regions (cusps) that allow the direct pen- etration of magnetosheath plasma through the exosphere of Mercury, till its surface. Target of the study is the evaluation of the sputtered particles from the crust of the planet, and their contribution to neutral particle production in the exosphere.

  14. Radiographic film dosimetry for IMRT fields in the nearsurface buildup region.

    PubMed

    Roberson, Peter L; Moran, Jean M; Kulasekere, Ravi

    2008-01-01

    Radiographic film dosimetry provides fast, convenient 2-D dose distributions, but is challenged by the dependence of film response on scatter conditions (i.e., energy dependence). Verification of delivered dose in the surface buildup region is important for intensity modulated radiation therapy (IMRT) when volumes of interest encroach on these regions (e.g., head/neck, breast). The current work demonstrates that film dosimetry can accurately predict the dose in the buildup region for IMRT, since 1) film dosimetry can be performed with sufficient accuracy for small fields and 2) IMRT is delivered by a series of "small" segments (step and shoot IMRT). This work evaluates the accuracy of X-OMAT V (XV) and Extended Dose Range (EDR) film for measurements from 2 mm to 15 mm depths for small fields and clinical IMRT beams. Film measurements have been compared to single point measurements made with a stereotactic diode and parallel plate ionization chamber (P11) and thermoluminescent dosimeters (TLD) at various depths for square (diode, P11) and IMRT (diode, TLD) fields. Film calibration was performed using an 8-field step exposure on a single film at 5 cm depth, which has been corrected to represent either small field or large field depth dependent film calibration techniques. Up to 10% correction for film response variation as a function of depth was required for measurements in the buildup region. A depth-dependent calibration can sufficiently improve the accuracy for IMRT calculation verification (i.e., < or = 5% uncertainty). A small field film calibration technique was most appropriate for IMRT field measurements. Improved buildup region dose measurements for clinical IMRT fields promotes improved dose estimation performance for (inverse) treatment planning and allows more quantitative treatment delivery validation. PMID:19020480

  15. Venus nightside ionospheric holes - The signatures of parallel electric field acceleration regions

    NASA Technical Reports Server (NTRS)

    Grebowsky, J. M.; Curtis, S. A.

    1981-01-01

    Attention is given to the existence of 'holes', that is, regions of density depletion in the nightside Venus ionosphere associated with regions of radial magnetic fields. The properties of the electrons within the core of these holes are thought to suggest an acceleration process along the magnetic field lines, a process also suggested by the Venera 9 and 10 observations of energetic ions in the Venus tail. On the basis of the observational information, these Venusian plasma depletions are attributed to the presence of parallel electric fields similar to those observed in the terrestrial auroral ionosphere. The resulting electric field accelerates electrons down the field lines, heating the depleted thermal electron population within the hole and producing ionization below the hole. At the same time, ionospheric ions are accelerated outward toward the plasmasheet.

  16. Pioneer 7 observations of plasma flow and field reversal regions in the distant geomagnetic tail

    NASA Technical Reports Server (NTRS)

    Walker, R. C.; Lazarus, A. J.; Villante, U.

    1975-01-01

    The present paper gives the results of an extensive analysis of plasma and magnetic-field data from Pioneer 7 taken in the geomagnetic tail approximately 1000 earth radii downstream from earth. The principal observations are: (1) measurable fluxes of protons in the tail, flowing away from earth, sometimes with a double-peaked velocity distribution; (2) field reversal regions in which the field changes from radial to antiradial by a vector rotation in the north-south plane; and (3) general characteristics of the tail similar to those observed near earth with good correlation between taillike magnetic fields and plasma.

  17. Model for the Coupled Evolution of Subsurface and Coronal Magnetic Fields in Solar Active Regions

    NASA Astrophysics Data System (ADS)

    van Ballegooijen, A. A.; Mackay, D. H.

    2007-04-01

    According to Babcock's theory of the solar dynamo, bipolar active regions are Ω-shaped loops emerging from a toroidal field located near the base of the convection zone. In this paper, a mean field model for the evolution of a twisted Ω-loop is developed. The model describes the coupled evolution of the magnetic field in the convection zone and the corona after the loop has fully emerged into the solar atmosphere. Such a coupled evolution is required to fully understand what happens to the coronal and subsurface fields as magnetic flux cancels at polarity inversion lines on the photosphere. The jump conditions for the magnetic field at the photosphere are derived from the magnetic stress balance between the convection zone and corona. The model reproduces the observed spreading of active region magnetic flux over the solar surface. At polarity inversion lines, magnetic flux submerges below the photosphere, but the component of magnetic field along the inversion line cannot submerge, because the field in the upper convection zone is nearly radial. Therefore, magnetic shear builds up in the corona above the inversion line, which eventually leads to a loss of equilibrium of the coronal fields and the ``lift-off'' of a coronal flux rope. Fields that submerge are transported back to the base of the convection zone, leading to the repair of the toroidal flux rope. Following Martens and Zwaan, interactions between bipoles are also considered.

  18. Calculating Non-Potentiality in Solar Active Regions Using SDO/HMI Vector Magnetic Field Data

    NASA Astrophysics Data System (ADS)

    Bobra, M.; Hoeksema, J. T.

    2010-12-01

    Non-potential magnetic fields in solar active regions are thought to be associated with flare occurrence. In this study, we parametrize the non-potentiality of several active regions, using data from the Helioseismic and Magnetic Imager (HMI) aboard the Solar Dynamics Observatory (SDO), and correlate these parameters with flare occurrence. In particular, we focus on a parameter that we call the Gradient-Weighted Inversion Line Length (GWILL). Using data from SOHO/MDI, Mason et al. found that GWILL generally tends to increase before a solar flare. We investigate whether extending the analysis of Mason et. al. to a three-dimensional field enables us to derive better near real-time indicators of flare occurrence. Before HMI, the availability of vector magnetograms was sparse at best. HMI provides continuous vector magnetogram data at a 12-minute cadence. As such, this study represents the first parametrization of non-potentiality in solar active regions using continuous vector magnetic field data.

  19. Stess field in Brazil: First and Second-Order Stress Patterns: Examples of Regional Forces Controlling the Stress Field

    NASA Astrophysics Data System (ADS)

    Dias, F.; Assumpcao, M.

    2012-12-01

    The knowledge of stress field is fundamental not only to understand driving forces and plate deformation as also it helps in the study of intraplate seismicity. In Brazil, we find reverse, strike-slip and normal mechanisms that indicates a variable stress field. The stress field has been mainly obtained using focal mechanism results and a few breakout data and in-situ measurements. However the stress field is still poorly known in Brazil. Recent earthquake focal mechanisms were determinate using P-wave modeling of seismogram stacks of several teleseismic stations ( > 30°) grouped according to distance and azimuth and first motion polarities. Every record was visually inspected and those with a good signal/noise ratio (SNR) were grouped in latitude-longitude windows of ten degrees and stacked. We usually consider groups with at least two stations, but, in sometimes a good record of single station with different azimuth was also used to constrain the focal depth. The P, pP, sP wavetrains of the stacked signals were modelled using the hudson96 program of Herrman seismology package (Herrman, 2002). We also determinate moment tensor of same events in the central region. The major difficulty is to determinate focal mechanism of low magnitudes events (< 4.0 mb) using distants seismograph stations. The central region shows a purely compressional pattern which are predicted by regional theoretical models (Richardson & Coblentz, 1996 and the TD0 model of Lithgow& Bertelloni, 2004). Meanwhile in the Amazonic region we find a SHmax from E-W to SE-NW probably caused by Caribbean and South American plates interaction (Meijer, 1995). In NE region, the compression rotates following the coast line which indicates an important component regional present in stress field spreading effects due to the continental/oceanic crustal (Assumpção, 1998) and cases of stress caused by sedimentary load in Amazon Fan in agreement local theoretical models (Watts et al., 2009). We determinate the

  20. The morphology of flare phenomena, magnetic fields, and electric currents in active regions. II - NOAA active region 5747 (1989 October)

    NASA Technical Reports Server (NTRS)

    Leka, K. D.; Canfield, Richard C.; Mcclymont, A. N.; De La Beaujardiere, J.-F.; Fan, Yuhong; Tang, F.

    1993-01-01

    The paper describes October 1989 observations in NOAA Active Region 5747 of the morphology of energetic electron precipitation and high-pressure coronal flare plasmas of three flares and their relation to the vector magnetic field and vertical electric currents. The H-alpha spectroheliograms were coaligned with the vector magnetograms using continuum images of sunspots, enabling positional accuracy of a few arcsec. It was found that, during the gradual phase, the regions of the H-alpha flare that show the effects of enhanced pressure in the overlying corona often encompass extrema of the vertical current density, consistent with earlier work showing a close relationship between H-alpha emission and line-of-sight currents. The data are also consistent with the overall morphology and evolution described by erupting-filament models such as those of Kopp and Pneuman (1976) and Sturrock (1989).

  1. The Mexico City Outflow and Its Regional Influence: A Regional Model Study in INTEX- B/MIRAGE Field Experiment

    NASA Astrophysics Data System (ADS)

    Tang, Y.; Carmichael, G. R.; Mena, M.; D'Allura, A.; Chai, T.; Pierce, R. B.; Al-Saadi, J. A.

    2006-12-01

    During the NASA INTEX-B and NSF MIRAGE field experiments in Spring of 2006, we applied a regional chemical transport model, STEM-2K3, to make nested forecasts coupled with a global model RAQMS by using its output as lateral and top boundary conditions. WRF mesoscale meteorological model was used to drive the regional model. The model predicted reasonable results compared with NASA DC-8 and NCAR C- 130 aircraft measurements over Mexico and Southern USA. Sulfate is the major ion in the Mexico City plume. Biomass/biofuel burning contributed to black carbon, though it became aged quickly during the transport process. Since aerosols and their precursors were usually co-emitted with gaseous pollutants from Mexico City, their interactions via direct reaction and radiative impacts became evident. The aerosol influence on photolysis rates depend not only on the aerosol optical depth, but also on the absorption portion or single scatter albedo (SSA). Sensitivity studies were performed to reveal the influence of aerosol SSA on photochemical processes over Mexico City and its downwind region. Due to the relatively high altitude of Mexico City, its outflow usually existed in middle troposphere over downwind regions. The radiative impact became a important portion of the influence of Mexico City plumes on downwind surface. The model study over Mexico City surface sites was also evaluated.

  2. On open and closed field line regions in Tsyganenko's field model and their possible associations with horse collar auroras

    NASA Technical Reports Server (NTRS)

    Birn, J.; Hones, E. W., Jr.; Craven, J. D.; Frank, L. A.; Elphinstone, R. D.; Stern, D. P.

    1991-01-01

    The boundary between open and closed field lines is investigated in the empirical Tsyganenko (1987) magnetic field model. All field lines extending to distances beyond -70 R(E), the tailward velocity limit of the Tsyganenko model are defined as open, while all other field lines, which cross the equatorial plane earthward of -70 R(E) and are connected with the earth at both ends, are assumed closed. It is found that this boundary at the surface of the earth, identified as the polar cap boundary, can exhibit the arrowhead shape, pointed toward the sun, which is found in horse collar auroras. For increasing activity levels, the polar cap increases in area and becomes rounder, so that the arrowhead shape is less pronounced. The presence of a net B(y) component can also lead to considerable rounding of the open flux region. The arrowhead shape is found to be closely associated with the increase of B(z) from the midnight region to the flanks of the tail, consistent with a similar increase of the plasma sheet thickness.

  3. Focal mechanisms of small earthquakes and the stress field in the western Quebec Adirondack region

    NASA Astrophysics Data System (ADS)

    Mareschal, Jean-Claude; Zhu, Pei-Ding

    1989-09-01

    Focal mechanisms were determined for 42 small earthquakes (1.4 < M < 3.4) that occurred in the Adirondacks-western Quebec seismic region. The analysis demonstrates the variability of the focal mechanisms and suggests that the region can be divided into two subprovinces with distinctive seismotectonic regimes: (1) in the Adirondacks, the focal mechanisms are mostly strike-slip with a comparatively smaller thrust component and indicate NNE compression: (2) in the western Quebec seismic region, the stress field is more heterogeneous and is dominated by two directions (NE and NW) of horizontal compression. This variable pattern suggests that the seismicity and stress field are controlled by regional plate stresses but are affected by local structures and/or by the predominant orientation of preexisting faults.

  4. The calculation of electromagnetic fields in the Fresnel and Fraunhofer regions using numerical integration methods

    NASA Technical Reports Server (NTRS)

    Schmidt, R. F.

    1971-01-01

    Some results obtained with a digital computer program written at Goddard Space Flight Center to obtain electromagnetic fields scattered by perfectly reflecting surfaces are presented. For purposes of illustration a paraboloidal reflector was illuminated at radio frequencies in the simulation for both receiving and transmitting modes of operation. Fields were computed in the Fresnel and Fraunhofer regions. A dual-reflector system (Cassegrain) was also simulated for the transmitting case, and fields were computed in the Fraunhofer region. Appended results include derivations which show that the vector Kirchhoff-Kottler formulation has an equivalent form requiring only incident magnetic fields as a driving function. Satisfaction of the radiation conditions at infinity by the equivalent form is demonstrated by a conversion from Cartesian to spherical vector operators. A subsequent development presents the formulation by which Fresnel or Fraunhofer patterns are obtainable for dual-reflector systems. A discussion of the time-average Poynting vector is also appended.

  5. Periodic auroral forms and geomagnetic field oscillations in the 1400 MLT region

    SciTech Connect

    Potemra, T.A. ); Vo, H.; Venkatesan, D.; Cogger, L.L. ); Erlandson, R.E.; Zanetti, L.J.; Bythrow, P.F.; Anderson, B.J. )

    1990-05-01

    The UV images obtained with the Viking satellite often show bright features which resemble beads or pearls aligned in the east-west direction between noon and 1800 MLT. Viking acquired a series of 25 UV images during a 28-min period on July 29, 1986, which showed a distinct series of periodic bright features in this region. Magnetic field and hot plasma measurements obtained by Viking confirm that the UV emissions are colocated with the field line projection of an upward-flowing region 1 Birkeland current and precipitating energetic ({approximately}200 eV) electrons. The magnetic field and electric field measurements show transverse oscillations with a nearly constant period of about 3.5 min from 67{degree} invariant latitude equatorward up to the location of the large-scale Birkeland current system near 76{degree} invariant latitude. The electric field oscillations lead the magnetic field oscillations by about a quarter-period. The authors interpret the observed oscillations as standing Alfven waves driven at a frequency near the local resonance frequency by a large-scale wave in the boundary layer. They propose that the energy flux of the precipitating low-energy electrons in this afternoon region is modulated by this boundary wave and produces the periodic UV emission features. The results of this study support the view that large-scale oscillations of magnetospheric boundaries, possibly associated with the Kelvin-Helmholtz instability, can modulate currents, particles, and auroral forms.

  6. On some properties of force-free magnetic fields in infinite regions of space

    NASA Technical Reports Server (NTRS)

    Aly, J. J.

    1984-01-01

    Techniques for solving boundary value problems (BVP) for a force free magnetic field (FFF) in infinite space are presented. A priori inequalities are defined which must be satisfied by the force-free equations. It is shown that upper bounds may be calculated for the magnetic energy of the region provided the value of the magnetic normal component at the boundary of the region can be shown to decay sufficiently fast at infinity. The results are employed to prove a nonexistence theorem for the BVP for the FFF in the spatial region. The implications of the theory for modeling the origins of solar flares are discussed.

  7. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    NASA Astrophysics Data System (ADS)

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-08-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that the pattern is complex, representing two constructional generations of dunes. The oldest and best-organized generation forms the primary crestlines and is transverse to circumpolar easterly winds. Gross bed form-normal analysis of the younger pattern of crestlines indicates that it emerged with both circumpolar easterly winds and NE winds and is reworking the older pattern. Mapping of secondary flow fields over the dunes indicates that the most recent transporting winds were from the NE. The younger pattern appears to represent an influx of sediment to the dune field associated with the development of the Olympia Cavi reentrant, with NE katabatic winds channeling through the reentrant. A model of the pattern reformation based upon the reconstructed primary winds and resulting secondary flow fields shows that the development of the secondary pattern is controlled by the boundary condition of the older dune topography.

  8. Four large-scale field-aligned current systems in the dayside high-latitude region

    SciTech Connect

    Ohtani, S.; Potemra, T.A.; Newell, P.T.

    1995-01-01

    A system of four current sheets of large-scale field-aligned currents (FACs) was discovered in the data set of simultaneous Viking and DMSP-F7 crossings of the dayside high-latitude region. This paper reports four examples of this system that were observed in the prenoon sector. The flow polarities of FACs are upward, downward, upward, and downward, from equatorward to poleward. The lowest-latitude upward current is flowing mostly in the CPS precipitation region, often overlapping with the BPS at its poleward edge, and is interpreted as a region 2 current. The pair of downward and upward FACs in the middle of the structure are collocated with structured electron precipitation. The precipitation of high-energy (>1 keV) electrons is more intense in the lower-latitude downward current sheet. The highest-latitude downward flowing current sheet is located in a weak, low-energy particle precipitation region, suggesting that this current is flowing on open field lines. Simultaneous observations in the postnoon local time sector reveal the standard three-sheet structure of FACs, sometimes described as region 2, region 1, and mantle (referred to the midday region 0) currents. A high correlation was found between the occurrence of the four FAC sheet structure and negative interplanetary magnetic field (IMF) B{sub Y}. The authors discuss the FAC structure in terms of three types of convection cells: the merging, viscous, and lobe cells. During strongly negative IMF B{sub Y}, two convection reversals exist in the prenoon sector; one is inside the viscous cell, and the other is between the viscous cell and the lobe cell. This structure of convection flow is supported by the Viking electric field and auroral UV image data. Based on the convection pattern, the four FAC sheet structure is interpreted as the latitudinal overlap of midday and morning FAC systems. 47 refs., 12 figs., 1 tab.

  9. On open and closed field line regions in Tsyganenko's field model and their possible associations with horse collar auroras

    SciTech Connect

    Birn, J.; Hones, E.W. Jr. ); Craven, J.D.; Frank, L.A. ); Elphinstone, R.D. ); Stern, D.P. )

    1991-03-01

    Using the empirical Tsyganenko (1987) long model as a prime example of a megnetospheric field model, the authors have attempted to identify the boundary between open and closed field lines. They define as closed all field lines that are connested with the Earth at both ends and cross the equatorial plane earthward of x = {minus}70 R{sub E}, the tailward validity limit of the Tsyganenko model. They find that the form of the open/closed boundary at the Earth's surface, identified with the polar cap boundary, can exhibit the arrowhead shape, pointed toward the Sun, observed in horse collar auroras (Hones et al., 1989). The polar cap size in the Tsyganenko model increases with increasing K{sub p} values, and it becomes rounder and less pointed. The superposition of a net B{sub y} field, which is the expected consequence of an IMF B{sub y}, rotates the polar cap pattern and, for larger values, degrades the arrowhead shape, resulting in polar cap configurations consistent with known asymmetries in the aurora. The pointedness of the polar cap shape also diminishes or even completely disappears if the low-latitude magnetopause is assumed open and located considerably inside of the outermost magnetic flux surface in the Tsyganenko model. The arrowhead shape of the polar cap is found to be associated with a strong increase of B{sub z} from midnight toward the tail flanks, which is observed independently, and is possibly related to the NBZ field-aligned current system, observed during quiet times and strongly northward IMF B{sub z}. The larger B{sub z} values near the flanks of the tail cause more magnetic flux to close through these regions than through the midnight equatorial region.

  10. UNAVCO Plate Boundary Observatory 2007 Student Field Assistant Program in the Alaska Region

    NASA Astrophysics Data System (ADS)

    Marzulla, A.; Gasparich, S.; Pauk, B.; Feaux, K.; Jackson, M.

    2007-12-01

    The UNAVCO, Inc. Plate Boundary Observatory (PBO) Student Field Assistant Program strives to engage students in further study and careers in the Earth Sciences. Student Field Assistants from a variety of educational backgrounds ranging from high school graduates to master's level students spend a three to five month field season working in tandem with UNAVCO regional Field Engineers. The students work closely with senior staff to reconnaissance, install, and maintain a network of 875 permanent Global Positioning System (GPS) stations in one of the five PBO regions covering the western United States, including Alaska. Practical skills, such as power tool use, drilling, welding, firearms training, and proper field safety procedures, are taught and expected of the students. Installation and maintenance of new and existing GPS stations composes the bulk of the student's responsibilities and duties. When not in the field, students prepare gear and arrange logistics for site installations and maintenance as well as enter metadata and complete installation reports from recently constructed sites. An understanding of the operations of the GPS receivers and the scientific benefit of the network allows for an appreciation and great attention to detail during installation of the sites. Student assistance in the Alaska region during 2007 PBO AK field season was critical to the successful installation of 36 new GPS stations throughout Alaska. Significant benchmarks of the field season included installing six logistically difficult stations in Prince William Sounds, completing the Denali Fault GPS network, four new tiltmeters on Akutan Volcano, completing all installs on the Seward Peninsula as well as several new GPS stations throughout the western interior of the state. Alaska is a prominent area for much movement and deformation as the Pacific Plate subducts beneath the North American Plate resulting in an area of high volcanic activity and heightened crustal deformation. The

  11. The Role of Active Region Coronal Magnetic Field in Determining Coronal Mass Ejection Propagation Direction

    NASA Astrophysics Data System (ADS)

    Wang, Rui; Liu, Ying D.; Dai, Xinghua; Yang, Zhongwei; Huang, Chong; Hu, Huidong

    2015-11-01

    We study the role of the coronal magnetic field configuration of an active region (AR) in determining the propagation direction of a coronal mass ejection (CME). The CME occurred in the AR 11944 (S09W01) near the disk center on 2014 January 7 and was associated with an X1.2 flare. A new CME reconstruction procedure based on a polarimetric technique is adopted, which shows that the CME changed its propagation direction by around 28° in latitude within 2.5 {R}⊙ and 43° in longitude within 6.5 {R}⊙ with respect to the CME source region. This significant non-radial motion is consistent with the finding of Möstl et al. We use nonlinear force-free field and potential field source surface extrapolation methods to determine the configurations of the coronal magnetic field. We also calculate the magnetic energy density distributions at different heights based on the extrapolations. Our results show that the AR coronal magnetic field has a strong influence on the CME propagation direction. This is consistent with the “channeling” by the AR coronal magnetic field itself, rather than deflection by nearby structures. These results indicate that the AR coronal magnetic field configuration has to be taken into account in order to determine CME propagation direction correctly.

  12. Rotating coil field measurement of superconducting magnet for BEPCII interaction region

    NASA Astrophysics Data System (ADS)

    Peng, Quanling; Ren, Fanglin; Yin, Baogui; Wu, Yingzhi; Dong, Lan; Sun, Zhirui

    2011-06-01

    Two multifunction superconducting magnets in the interaction region (IR) for Beijing electron positron collider upgrade project (BEPCII) have been measured in BESIII detector hall in 2007. Each superconducting magnet package contains multiple concentric layers with several function magnets called as a vertical focusing quadrupole (SCQ), a horizontal corrector (HDC/SCB), a vertical corrector (VDC), a skew quadrupole (SKQ) and three anti-solenoids (AS1, AS2 and AS3) to compensate the experimental detector solenoid field. All these function magnets SCQs, SCB/HDCs, VDCs and SKQs have been measured using two rotating coils. Their integral fields, their high order harmonics contents and the local fields along the beam line are obtained in detail with the rotating coil probe system. Comparing the results to the stretched wire, the differences for the integral fields are less than 0.2%. As a result, the method presented in this paper can be used as an absolute field measurement in our lab.

  13. Mapping land-surface fluxes of carbon, water and energy from field to regional scales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A framework for routine mapping of land-surface fluxes of carbon, water, and energy at the field to regional scales has been established for drought monitoring, water resource management, yield forecasting and crop-growth monitoring. The framework uses the ALEXI/DisALEXI suite of land-surface model...

  14. The magnetic field structure in high-mass star formation regions

    NASA Technical Reports Server (NTRS)

    Davidson, Jacqueline A.; Schleuning, D.; Dotson, J. L.; Dowell, C. Darren; Hildebrand, Roger H.

    1995-01-01

    We present a preliminary analysis of far-IR polarimetric observations, which were made to study the magnetic field structure in the high-mass star formation regions of M42, NGC2024, and W3. These observations were made from the Kuiper Airborne Observatory (KAO), using the University of Chicago far-IR polarimeter, Stokes.

  15. Statistical analysis of multipole components in the magnetic field of the RHIC arc regions

    SciTech Connect

    Beebe-Wang,J.; Jain, A.

    2009-05-04

    The existence of multipolar components in the dipole and quadrupole magnets is one of the factors limiting the beam stability in the RHIC operations. Therefore, the statistical properties of the non-linear fields are crucial for understanding the beam behavior and for achieving the superior performance in RHIC. In an earlier work [1], the field quality analysis of the RHIC interaction regions (IR) was presented. Furthermore, a procedure for developing non-linear IR models constructed from measured multipolar data of RHIC IR magnets was described. However, the field quality in the regions outside of the RHIC IR had not yet been addressed. In this paper, we present the statistical analysis of multipolar components in the magnetic fields of the RHIC arc regions. The emphasis is on the lower order components, especially the sextupole in the arc dipole and the 12-pole in the quadrupole magnets, since they are shown to have the strongest effects on the beam stability. Finally, the inclusion of the measured multipolar components data of RHIC arc regions and their statistical properties into tracking models is discussed.

  16. LOS COLEGIOS REGIONALES, OPORTUNIDADES DE ESTUDIO EN INSTITUCIONES DE NIVEL UNIVERSITARIO. (THE REGIONAL COLLEGES, OPPORTUNITIES FOR STUDY IN UNIVERSITY LEVEL INSTITUTIONS).

    ERIC Educational Resources Information Center

    BETANCOURT, ETHEL RIOS DE; AND OTHERS

    RECENT LEGISLATION IN PUERTO RICO HAS VALIDATED THE 2-YEAR REGIONAL COLLEGE CONCEPT, AND THE CHARACTER OF THE PROGRAM COMBINING LIBERAL ARTS TRANSFER CURRICULUMS AND VOCATIONAL EDUCATION HAS BEEN SET. TO IMPLEMENT THE PLANNING PHASES, THIS STUDY PREDICTS STUDENT ENROLLMENT BY REGION. TWO INDEXES ARE USED TO ESTIMATE STUDENT DEMAND--COLLEGE…

  17. Methane flux measurements from paddy fields in the tropical Indian region

    NASA Astrophysics Data System (ADS)

    Lal, Shyam; Venkataramani, S.; Subbaraya, B. H.

    Methane flux measurements have been made from paddy fields in the Thanjavur region in southern India from September 1991 to January 1992. This is a major rice growing area having plenty of river and rain water. A perspex chamber was used to cover the plants. Samples from this chamber were collected using a metal bellows pump in small sample bottles. The methane flux values estimated from the analysis of these samples are mostly in the range of 15-25 mg m -2h -1. These preliminary results, from natural fields, give higher flux values than estimates from some other regions in India, as well as average values for the mid-latitude region, but values lower than from China.

  18. On the regularization of regional gravity field solutions in spherical radial base functions

    NASA Astrophysics Data System (ADS)

    Naeimi, Majid; Flury, Jakob; Brieden, Phillip

    2015-08-01

    Regional refinement of the gravity field models from satellite data using spherical radial base functions (SRBF) is an ill-posed problem. This is mainly due to the regional confinement of the data and the base functions, which leads to severe instabilities in the solutions. Here, this ill-posedness as well as the related regularization process are investigated. We compare three methods for the choice of the regularization parameter, which have been frequently used in gravity modelling. These methods are (1) the variance component estimation (VCE), (2) the generalized cross validation (GCV) and (3) the L-curve criterion. A particular emphasis is put on the impact of the SRBF type on the regularization parameter. To do this, we include two types of SRBF which are often used for regional gravity field modelling. These are the Shannon SRBF or the reproducing kernel and the Spline SRBF. The investigations are performed on two months of the real GOCE ultrasensitive gravity gradients over Central Africa and Amazon. The solutions are validated against a state-of-the-art global gravity solution. We conclude that if a proper regularization method is applied, both SRBF deliver more or less the same accuracy. We show that when the Shannon wavelet is used, the L-curve method gives the best results, while with the Spline kernel, the GCV outperforms the other two methods. Moreover, we observe that the estimated coefficients for the Spline kernel cannot be spatially interpreted. In contrast, the coefficients obtained for the Shannon wavelet reflect the energy of the recovered gravity field with a correlation factor of above 95 per cent. Therefore, when combined with the L-curve method, the Shannon SRBF is advantageous for regional gravity field estimation, since it is one of the simplest band-limited SRBF. In addition, it delivers promising solutions and the estimated coefficients represent the characteristics of the gravity field within the target region.

  19. Plasma regions, charged dust and field-aligned currents near Enceladus

    NASA Astrophysics Data System (ADS)

    Engelhardt, I. A. D.; Wahlund, J.-E.; Andrews, D. J.; Eriksson, A. I.; Ye, S.; Kurth, W. S.; Gurnett, D. A.; Morooka, M. W.; Farrell, W. M.; Dougherty, M. K.

    2015-11-01

    We use data from several instruments on board Cassini to determine the characteristics of the plasma and dust regions around Saturn's moon Enceladus. For this we utilize the Langmuir probe and the electric antenna connected to the wideband receiver of the radio and plasma wave science (RPWS) instrument package as well as the magnetometer (MAG). We show that there are several distinct plasma and dust regions around Enceladus. Specifically they are the plume filled with neutral gas, plasma, and charged dust, with a distinct edge boundary region. Here we present observations of a new distinct plasma region, being a dust trail on the downstream side. This is seen both as a difference in ion and electron densities, indicating the presence of charged dust, and directly from the signals created on RPWS antennas by the dust impacts on the spacecraft. Furthermore, we show a very good scaling of these two independent dust density measurement methods over four orders of magnitude in dust density, thereby for the first time cross-validating them. To establish equilibrium with the surrounding plasma the dust becomes negatively charged by attracting free electrons. The dust distribution follows a simple power law and the smallest dust particles in the dust trail region are found to be 10 nm in size as well as in the edge region around the plume. Inside the plume the presence of even smaller particles of about 1 nm is inferred. From the magnetic field measurements we infer strong field-aligned currents at the geometrical edge of Enceladus.

  20. Earth's Magnetic Field Monitoring in the AMAS Region with the NANOSATC-BR1 Nanosatellite

    NASA Astrophysics Data System (ADS)

    Bilibio, Andreos Vestena; Schuch, Nelson Jorge; Denardini, Clezio Marcos; Mendes, Odim; Marchezi, Jose Paulo; Cupertino Durao, Otavio S.

    The objectives of the Southern Regional Space Research Center's Solar Physics and Interplanetary Medium & Magnetosphere Laboratory is to study Geomagnetic field techniques in experimental measurements and monitoring changes in the South Atlantic Magnetic Anomaly (SAMA) region by continuous measurements of the three orthogonal components of Geomagnetic field: H (North-South), D (East- West) and Z (vertical down). The observation measurements are made at the Southern Space Observatory - SSO/CRS/INPE - MCTI in São Martinho da Serra (29.43º S, 53.82º W, elevation 488m), southern Brazil. Nanosatellites, such as CubeSats, have been used in many scientific space applications. The NANOSATC-BR1 is the second nanosatellite of the NANOSATC-BR, Development of CubeSats Program, a Brazilian Partnership between INPE/MCTI & UFSM. The NANOSATC-BR1 Project has been planed, designed and executed in the facilities built on the partnership between CRS/INPE/MCTI and the Federal University of Santa Maria (LACESM/CT-UFSM), with its undergraduate students. The nanosatellite has three payloads: two integrated circuits (designed in Brazil for space use) to be tested for radiation resistance and a fluxgate magnetometer (model XEM - 12.10 FGM), that will be used for geomagnetic field measurements over the AMAS region. The magnetometer is a magnetic field sensor based on the Hall effect. The instrument will perform data collection in a frequency of three samples per seconds, with a resolution of 15 nT for magnetic field intensity. The intention for future studies is to do comparison between SSO data and monitoring the spatial and temporal variation of magnetic field intensity in AMAS region.

  1. Extensive lava flow fields on Venus: Preliminary investigation of source elevation and regional slope variations

    NASA Technical Reports Server (NTRS)

    Magee-Roberts, K.; Head, James W., III; Lancaster, M. G.

    1992-01-01

    Large-volume lava flow fields have been identified on Venus, the most areally extensive of which are known as fluctus and have been subdivided into six morphologic types. Sheetlike flow fields (Type 1) lack the numerous, closely spaced, discrete lava flow lobes that characterize digitate flow fields. Transitional flow fields (Type 2) are similar to sheetlike flow fields but contain one or more broad flow lobes. Digitate flow fields are divided further into divergent (Types 3-5) and subparallel (Type 6) classes on the basis of variations in the amount of downstream flow divergence. As a result of our previous analysis of the detailed morphology, stratigraphy, and tectonic associations of Mylitta Fluctus, we have formulated a number of questions to apply to all large flow fields on Venus. In particular, we would like to address the following: (1) eruption conditions and style of flow emplacement (effusion rate, eruption duration), (2) the nature of magma storage zones (presence of neutral buoyancy zones, deep or shallow crustal magma chambers), (3) the origin of melt and possible link to mantle plumes, and (4) the importance of large flow fields in plains evolution. To answer these questions we have begun to examine variations in flow field dimension and morphology; the distribution of large flow fields in terms of elevation above the mean planetary radius; links to regional tectonic or volcanic structures (e.g., associations with large shield edifices, coronae, or rift zones); statigraphic relationships between large flow fields, volcanic plains, shields, and coronae; and various models of flow emplacement in order to estimate eruption parameters. In this particular study, we have examined the proximal elevations and topographic slopes of 16 of the most distinctive flow fields that represent each of the 6 morphologic types.

  2. Penetration of fields described by the Klein-Gordon equation into supercritical regions of inhomogeneous media

    SciTech Connect

    Gromov, E.M.; Talanov, V.I.

    1992-01-01

    Questions relating to the penetration of fields into supercritical regions of inhomogeneous media are of considerable interest both for fundamental studies in wave theory and for applied problems in various areas of physics. In strong fields this penetration is related to nonlinear restructuring of the parameters of the medium under the action of the field itself. In weak fields penetration is possible when a strong wave in the parameters of the medium is present and are facilitated if the dynamic states undergo frequency shifts in the inhomogeneous medium in the presence of this wave. Such states have been quite well studied for fields described by equations such as the Schroedinger equation. At the same time it was noted that dynamic field states can exist which are described by the Klein-Gordon equation. In the present work we study the dynamic states of such fields in the presence of a parameter wave. We point out the possibility of entraining packets of the field by this wave. The efficiency with which these entrained states are excited is determined for a parameter wave in the form of a discontinuous shock. 12 refs.

  3. Three-dimensional magnetic field topology in a region of solar coronal heating.

    PubMed

    Solanki, S K; Lagg, A; Woch, J; Krupp, N; Collados, M

    2003-10-16

    Flares and X-ray jets on the Sun arise in active regions where magnetic flux emerges from the solar interior amd interacts with the ambient magnetic field. The interactions are believed to occur in electric current sheets separating regions of opposite magnetic polarity. The current sheets located in the corona or upper chromosphere have long been thought to act as an important source of coronal heating, requiring their location in the corona or upper chromosphere. The dynamics and energetics of these sheets are governed by a complex magnetic field structure that, until now, has been difficult to measure. Here we report the determination of the full magnetic vector in an interaction region near the base of the solar corona. The observations reveal two magnetic features that characterize young active regions on the Sun: a set of rising magnetic loops and a tangential discontinuity of the magnetic field direction, the latter being the observational signature of an electric current sheet. This provides strong support for coronal heating models based on the dissipation of magnetic energy at current sheets. PMID:14562096

  4. The EM fields in the Solid Generated by a Fault in a Porous Region

    NASA Astrophysics Data System (ADS)

    Ren, H.; Huang, Q.; Chen, X.

    2015-12-01

    Electrokinetic effect, as one of the most possible generation mechanisms of the seismo-electromagnetic phenomenons associated with natural earthquakes, has interested many researchers. Besides, it is also considered as a potential tool for the water/oil exploration. Recently, we numerically investigated the electromagnetic (EM) fields due to the electrokinetic effect in mixed layered model. The mixed model comprises not only porous layers but also solid layers. We firstly tested a two-layer mixed model. The numerical results show that, in addition to the radiation EM fields, another kind of evanescent EM fields can be generated by the seismic waves arriving at the interface with incident angles greater the critical angle. The evanescent EM fields decay faster than the radiation EM fields when getting away from the interface. For the seismic frequency band, the evanescent EM fields in the solid are still measurable at a distance of, e.g., 2km to the interface. We then tested a eight-layer mixed model. The top and bottom layers are solid and the other layers are porous. A finite fault of 20x10km is located in the porous region. The focal depth is 8km. The applied source time function is a ramp fuction with an arise time of 0.8s. Point stacking method was used to compute the wave-fields caused by the finite fault. Our nuemrical results show that, this model can generate the EM fields before the arrival of seismic waves as well as the residual EM fields. Both the two kinds of EM fields have been observed in field observations. There is a possibility that the anomalous EM activities before big earthquakes may be caused by the fluid flow in the shallow Earth as a result of the stress changes.

  5. Hamiltonian description of the parametrized scalar field in bounded spatial regions

    NASA Astrophysics Data System (ADS)

    Barbero G, J. Fernando; Margalef-Bentabol, Juan; Villaseñor, Eduardo J. S.

    2016-05-01

    We study the Hamiltonian formulation for a parametrized scalar field in a regular bounded spatial region subject to Dirichlet, Neumann and Robin boundary conditions. We generalize the work carried out by a number of authors on parametrized field systems to the interesting case where spatial boundaries are present. The configuration space of our models contains both smooth scalar fields defined on the spatial manifold and spacelike embeddings from the spatial manifold to a target spacetime endowed with a fixed Lorentzian background metric. We pay particular attention to the geometry of the infinite dimensional manifold of embeddings and the description of the relevant geometric objects: the symplectic form on the primary constraint submanifold and the Hamiltonian vector fields defined on it.

  6. Examining the Magnetic Field Strength and the Horizontal and Vertical Motions in an Emerging Active Region

    NASA Astrophysics Data System (ADS)

    Lin, Chia-Hsien; Chen, Yu-Che

    2016-03-01

    Earlier observational studies have used the time evolution of emerging magnetic flux regions at the photosphere to infer their subsurface structures, assuming that the flux structure does not change significantly over the near-surface layer. In this study, we test the validity of this assumption by comparing the horizontal and vertical motions of an emerging active region. The two motions would be correlated if the emerging structure is rigid. The selected active region (AR) NOAA 11645 is not embedded in detectable preexisting magnetic field. The observed horizontal motion is quantified by the separation of the two AR polarities and the width of the region. The vertical motion is derived from the magnetic buoyancy theory. Our results show that the separation of the polarities is fastest at the beginning with a velocity of {≈ }4 Mm hr^{-1} and decreases to ≤ 1 Mm hr^{-1} after the main growing phase of flux emergence. The derived thick flux-tube buoyant velocity is between 1 and 3 Mm hr^{-1}, while the thin flux-tube approximation results in an unreasonably high buoyant velocity, consistent with the expectation that the approximation is inappropriate at the surface layer. The observed horizontal motion is not found to directly correlate with either the magnetic field strength or the derived buoyant velocities. However, the percentage of the horizontally oriented fields and the temporal derivatives of the field strength and the buoyant velocity show some positive correlations with the separation velocity. The results of this study imply that the assumption that the emerging active region is the cross section of a rising flux tube whose structure can be considered rigid as it rises through the near-surface layer should be taken with caution.

  7. Modeling of regional meteorological fields with high spatial resolution for West Siberia

    NASA Astrophysics Data System (ADS)

    Bogomolov, Vasiliy; Gordov, Evgeny

    2010-05-01

    As well known, global climate changes are inhomogeneous that is most clearly pronounced in the northern regions of the Earth. To study these inhomogeneities and trends, it is necessary to analyze climate changes in the ХХ century in the specific region. Now data of different reanalyses (USA, Europe, Japan), as well as observational data from weather stations, are used for such an analysis. Modeling data validity is mostly determined by amount of assimilated measurement data and by weather station network density. For example, for the 2nd edition of USA reanalysis, data of only 300 weather stations of Russian Federation have been used, where most stations are located in European part of the country. Comparison of meteorological fields obtained using reanalysis to measurements of Rosgidromet weather stations gives significant discrepancy. Reanalyses spatial resolution does not allow studying local inhomogeneities that inherent to regional climate changes. Therefore to study local climate dynamics in Siberian region, it is necessary to calculate meteorological fields with higher spatial resolution. Modern mesoscale meteorological models that use reanalyses archives and assimilate measurements of weather stations can solve this problem. We calculated fields of climatic characteristics for West Siberia for the period from 1960 to 2000. The regional weather forecast WRF model (http://www.mmm.ucar.edu/modeling/wrf/index.php) and data assimilation system WRF-VAR (WRFDA) have been installed and debugged on the base of multiprocessor computational complex. Vertical boundary conditions, as well as initial conditions are formed using ERA-40 reanalysis data. NCEP data and USGS map with spatial resolution of 9.25 km are used for the lower boundary, measurements of weather stations, located within calculation area, are used for observation nudging. As a result of the model run, we have meteorological fields, which are reanalysis fields' projections with high spatial resolution

  8. Combination of various observation techniques for regional modeling of the gravity field

    NASA Astrophysics Data System (ADS)

    Lieb, Verena; Schmidt, Michael; Dettmering, Denise; Börger, Klaus

    2016-05-01

    Modeling a very broad spectrum of the Earth's gravity field needs observations from various measurement techniques with different spectral sensitivities. Typically, high-resolution regional gravity data are combined with low-resolution global observations. To exploit the gravitational information as optimally as possible, we set up a regional modeling approach using radial spherical basis functions, emphasizing the strengths of various data sets by the flexible combination of high- and middle-resolution terrestrial, airborne, shipborne, and altimetry measurements. The basis functions are defined and located in the region of interest in such a manner, which the highest measure of information of the input data is captured. Any functional of the Earth's gravity field can be derived, as, e.g., quasi-geoid heights or gravity anomalies. Here we present results of a study area in Northern Germany. A comprehensive cross validation to external observation data delivers standard deviations less than 5 cm. Differences to an existing regional quasi-geoid model count on average ±6 cm and proof the plausibility of our solution. The comparison with existing global models reaches higher standard deviations for the more sensitive gravity anomalies as for quasi-geoid heights, showing the additional value of our solution in the high frequency domain. Covering a broad frequency spectrum, our regional models can be used as basis for various applications, such as refinement of global models, national geoid determination, and detection of mass anomalies in the Earth's interior.

  9. Flow-Field Survey in the Test Region of the SR-71 Aircraft Test Bed Configuration

    NASA Technical Reports Server (NTRS)

    Mizukami, Masashi; Jones, Daniel; Weinstock, Vladimir D.

    2000-01-01

    A flat plate and faired pod have been mounted on a NASA SR-71A aircraft for use as a supersonic flight experiment test bed. A test article can be placed on the flat plate; the pod can contain supporting systems. A series of test flights has been conducted to validate this test bed configuration. Flight speeds to a maximum of Mach 3.0 have been attained. Steady-state sideslip maneuvers to a maximum of 2 deg have been conducted, and the flow field in the test region has been surveyed. Two total-pressure rakes, each with two flow-angle probes, have been placed in the expected vicinity of an experiment. Static-pressure measurements have been made on the flat plate. At subsonic and low supersonic speeds with no sideslip, the flow in the surveyed region is quite uniform. During sideslip maneuvers, localized flow distortions impinge on the test region. Aircraft sideslip does not produce a uniform sidewash over the test region. At speeds faster than Mach 1.5, variable-pressure distortions were observed in the test region. Boundary-layer thickness on the flat plate at the rake was less than 2.1 in. For future experiments, a more focused and detailed flow-field survey than this one would be desirable.

  10. Observations of photospheric magnetic fields and shear flows in flaring active regions

    NASA Technical Reports Server (NTRS)

    Tarbell, T.; Ferguson, S.; Frank, Z.; Title, A.; Topka, K.

    1988-01-01

    Horizontal flows in the photosphere and subsurface convection zone move the footpoints of coronal magnetic field lines. Magnetic energy to power flares can be stored in the corona if the flows drive the fields far from the potential configuration. Videodisk movies were shown with 0.5 to 1 arcsecond resolution of the following simultaneous observations: green continuum, longitudinal magnetogram, Fe I 5576 A line center (mid-photosphere), H alpha wings, and H alpha line center. The movies show a 90 x 90 arcsecond field of view of an active region at S29, W11. When viewed at speeds of a few thousand times real-time, the photospheric movies clearly show the active region fields being distorted by a remarkable combination of systematic flows and small eruptions of new flux. Magnetic bipoles are emerging over a large area, and the polarities are systematically flowing apart. The horizontal flows were mapped in detail from the continuum movies, and these may be used to predict the future evolution of the region. The horizontal flows are not discernable in H alpha. The H alpha movies strongly suggest reconnection processes in the fibrils joining opposite polarities. When viewed in combination with the magnetic movies, the cause for this evolution is apparent: opposite polarity fields collide and partially cancel, and the fibrils reconnect above the surface. This type of reconnection, driven by subphotospheric flows, complicates the chromospheric and coronal fields, causing visible braiding and twisting of the fibrils. Some of the transient emission events in the fibrils and adjacent plage may also be related.

  11. Ozone formation along the California-Mexican border region during Cal-Mex 2010 field campaign

    NASA Astrophysics Data System (ADS)

    Li, Guohui; Bei, Naifang; Zavala, Miguel; Molina, Luisa T.

    2014-05-01

    The purpose of this study is to evaluate the ozone (O3) formation along the California-Mexico border region using the WRF-CHEM model in association with the Cal-Mex 2010 field campaign. Four two-day episodes in 2010 are chosen based on plume transport patterns: 1) May 15-16 (plume north), 2) May 29-30 (plume southwest), 3) June 4-5 (plume east), and 4) June 13-14 (plume southeast). Generally, the predicted O3 spatial patterns and temporal variations agree well with the observations at the ambient monitoring sites in the San Diego-Tijuana region, but in the Calexico-Mexicali region, the model frequently underestimates the observation. In the San Diego-Tijuana region, the morning anthropogenic precursor emissions in the urbanized coastal plain are carried inland and mixed with the local biogenic emissions during transport, causing the high O3 level over the mountain region. Biogenic emissions enhance the O3 concentrations by up to 40 ppb over the mountain region in the afternoon. The factor separation approach is used to evaluate the contributions of trans-boundary transport of emissions from California and Baja California to the O3 level in the California-Mexico border region. The Baja California emissions play a minor role in the O3 formation in the San Diego region and do not seem to contribute to the O3 exceedances in the region, but have large potential to cause O3 exceedances in the Calexico region. The California emissions can considerably enhance the O3 level in the Tijuana region. Generally, the California emissions play a more important role than the Baja California emissions on O3 formation in the border region (within 40 km to the California-Mexico border). On average, the O3 concentrations in the border region are decreased by 2-4 ppb in the afternoon due to the interactions of emissions from California and Baja California. Further studies need to be conducted to improve the sea breeze simulations in the border region for evaluating O3 formation.

  12. Reorganization of Photospheric Magnetic Fields in Active Regions During Energetic Flares

    NASA Astrophysics Data System (ADS)

    Santos, J. C.; Wrasse, C. M.

    2016-04-01

    The reorganization of the photospheric magnetic field may be important for flaring activity. In this work we use the time evolution of the magnetic power spectra to identify for which length scales the reorganization of the active region magnetic field is most closely related to energetic flares. Our results show that the reorganization occurs mainly for length scales larger than 12.6 Mm and may start much before the time of the flare, but the time evolution of magnetic power spectra does not show regular patterns. An analysis of the dissipation spectra suggests that the dissipation takes place at all spatial scales, including small wavenumbers in which more energy is available.

  13. Numerical calculation of the three dimensional electrical field in the central region of a cyclotron

    SciTech Connect

    Chen, M.; Lind, D. A.

    1981-01-01

    To provide detailed and accurate electric fields in the ion source-puller region and at the dee dummy-dee gap for a cyclotron, a relaxation method solution of Laplace's equation has been used. A conventional difference equation with variation in mesh size and relaxation factor as well as different schemes for boundary corrections have been developed to achieve roughly 1 percent accuracy for a thre-dimensional domain with 10/sup 6/ mesh points. Although the computation requires considerable computer time, it is much less expensive than electrolytic tank analogue methods for measuring field distributions around complex electrode configurations.

  14. Importance of far-field Topographic and Isostatic corrections for regional density modeling

    NASA Astrophysics Data System (ADS)

    Szwillus, Ebbing, Holzrichter

    2016-07-01

    The long-wavelength gravity field contains information about processes in the sub-lithospheric mantle. As satellite-derived gravity models now provide the long to medium-wavelength gravity field at unprecedented accuracy, techniques used to process gravity data need to be updated. We show that when determining these long-wavelengths, the treatment of topographic and isostatic effects is a likely source of error. We constructed a global isostatic model and calculated global topographic and isostatic effect. These calculations were done for ground stations as well as stations at satellite height. We considered both gravity and gravity gradients. Using these results, we determined how much of the gravity signal comes from distant sources. We find that a significant long-wavelength bias is introduced if far-field effects on the topographic effect are neglected. However, due to isostatic compensation far-field effects of the topographic effect are to a large degree compensated by the far-field isostatic effect. This means that far-field effects can be reduced effectively by always considering topographic masses together with their compensating isostatic masses. We show that to correctly represent the ultra-long wavelengths, a global background model should be used. This is demonstrated both globally and for a continental-scale case area in North America. In the case of regional modeling, where the ultra-long wavelengths are not of prime importance, gravity gradients can be used to help minimize correction errors caused by far-field effects.

  15. Merged interaction regions and large-scale magnetic field fluctuations during 1991: Voyager 2 observations

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Ness, N. F.

    1994-01-01

    This paper analyzes Voyager 2 observations of the magnetic field between 33.6 AU and 36.2 AU during 1991 when extraordinary events were observed on the Sun and in the heliosphere. The magnetic field strength signal B(t) has the unusual form of two large transient merged interaction regions (MIRs) on a fluctuating background. The two MIRs moved past the spacecraft in 32 days and 18 days, respectively. The mean field strength in each transient MIR was approx. equals 2.6 times the mean field during the remaining part of the year (0.11 nT). Each of the MIRs is related to a fast stream. The magnetic field is strong throughout each stream, suggesting that the strong fields are carried by the streams as well as produced by shock and stream compression. The fluctuations in B(t) during 1991 are not multifractal, and the MIRs cannot be approximated as multifractal clusters of intense magnetic fields. The distribution of the hour-averaged magnetic field strengths is approximately lognormal over 90% of its intermediate range, and it has an exponential tail for B greater than the average magnetic field strength. The elevation angles of B have a normal distribution with a standard deviation of 16 deg +/- 4 deg. The distributions of the azimuthal angles of B in the ranges 1 deg - 180 deg and 180 deg - 360 deg are approximately normal over a more limited range, and non-Gaussian tails associated with nearly radial magnetic fields; the standard deviations are approx. equal to 40 deg. Individual sectors are present throughout most of the interval, even in the MIRs, but there is no recurrent sector pattern. A model of the large-scale fluctuations in 1991 will have to include both determinaistic and statistical factors.

  16. SITE IVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: OCTOBER 2005 – SEPTEMBER 2006

    EPA Science Inventory

    Site Investigations (SIs) and expanded Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Pl...

  17. SITE IVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: AUGUST 2007 – SEPTEMBER 2008

    EPA Science Inventory

    Site Investigations (SIs) and Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Project Pla...

  18. SITE INVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: OCTOBER 2006 – JULY 2007

    EPA Science Inventory

    Site Investigations (SIs) and Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Project Pla...

  19. Effect of Interhemispheric Field-Aligned Currents on Region-1 Currents

    NASA Technical Reports Server (NTRS)

    Lyatsky, Sonya; Lyatsky, Wladislaw; Khazanov, George V.

    2015-01-01

    An asymmetry in ionospheric conductivity between two hemispheres results in the formation of additional, interhemispheric field-aligned currents flowing between conjugate ionospheres within two auroral zones. These interhemispheric currents are especially significant during summer-winter conditions when there is a significant asymmetry in ionospheric conductivity in two hemispheres. In such conditions, these currents may be comparable in magnitude with the Region 1 field-aligned currents. In this case, the R1 current is the sum of two FACs: one is going from to the solar wind, and another is flowing between conjugate ionospheres. These interhemispheric currents can also cause the formation of auroras extended along the nightside polar cap boundary, which may be related to the so-called double auroral oval. In this study, we present the results of analytical and numerical solutions for the interhemispheric currents and their effect on the Region 1 currents.

  20. Geopotential field anomalies and regional tectonic features - two case studies: southern Africa and Germany

    NASA Astrophysics Data System (ADS)

    Korte, Monika; Mandea, Mioara

    2016-05-01

    Maps of magnetic and gravity field anomalies provide information about physical properties of the Earth's crust and upper mantle, helpful in understanding geological conditions and tectonic structures. Depending on data availability, whether from the ground, airborne, or from satellites, potential field anomaly maps contain information on different ranges of spatial wavelengths, roughly corresponding to sources at different depths. Focussing on magnetic data, we compare amplitudes and characteristics of anomalies from maps based on various available data and as measured at geomagnetic repeat stations. Two cases are investigated: southern Africa, characterized by geologically old cratons and strong magnetic anomalies, and the smaller region of Germany with much younger crust and weaker anomalies. Estimating lithospheric magnetic anomaly values from the ground stations' time series (repeat station crustal biases) reveals magnetospheric field contributions causing time-varying offsets of several nT in the results. Similar influences might be one source of discrepancy when merging anomaly maps from different epochs. Moreover, we take advantage of recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of ˜ 200 km resolution. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Comparing short- and long-wavelength anomalies and the correlation of rather large-scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement in the southern African region than the German region. This probably indicates stronger concordance between near-surface (down to at most a few km) and deeper (several kilometres down to Curie depth) structures in the former area, which can be seen to agree with a thicker lithosphere and a lower heat flux reported in the literature for the southern

  1. Four large-scale field-aligned current systmes in the dayside high-latitude region

    NASA Technical Reports Server (NTRS)

    Ohtani, S.; Potemra, T. A.; Newell, P.T.; Zanetti, L. J.; Iijima, T.; Watanabe, M.; Blomberg, L. G.; Elphinstone, R. D.; Murphree, J. S.; Yamauchi, M.

    1995-01-01

    A system of four current sheets of large-scale field-aligned currents (FACs) was discovered in the data set of simultaneous Viking and Defense Meteorological Satellire Program-F7 (DMSP-F7) crossing of the dayside high-latitude region. This paper reports four examples of this system that were observed in the prenoon sector. The flow polarities of FACs are upward, downward, upward, and downward, from equatorward to poleward. The lowest-latitude upward current is flowing mostly in the central plasma sheet (CPS) precipitation region, often overlapping with the boundary plasma sheet (BPS) at its poleward edge, andis interpreted as a region 2 current. The pair of downward and upward FACs in the middle of te structure are collocated with structured electron precipitation. The precipitation of high-energy (greater than 1 keV) electrons is more intense in the lower-latitude downward current sheet. The highest-latitude downward flowing current sheet is located in a weak, low-energy particle precipitation region, suggesting that this current is flowing on open field lines. Simulaneous observations in the postnoon local time sector reveal the standard three-sheet structure of FACs, sometimes described as region 2, region 1, and mantle (referred to the midday region O) currents. A high correlation was found between the occurrence of the four FAC sheet structure and negative interplanetary magnetic field (IMF) B(sub Y). We discuss the FAC structurein terms of three types of convection cells: the merging, viscous, andlobe cells. During strongly negative IMF B(sub Y), two convection reversals exist in the prenoon sector; one is inside the viscous cell, and the other is between the viscous cell and the lobe cell. This structure of convection flow is supported by the Viking electric field and auroral UV image data. Based on the convection pattern, the four FAC sheet structure is interpreted as the latitude overlap of midday and morning FAC systems. We suggest that the for

  2. Gamma–Gamma Absorption in the Broad Line Region Radiation Fields of Gamma-Ray Blazars

    NASA Astrophysics Data System (ADS)

    Böttcher, Markus; Els, Paul

    2016-04-01

    The expected level of γγ absorption in the Broad Line Region (BLR) radiation field of γ-ray loud Flat Spectrum Radio Quasars (FSRQs) is evaluated as a function of the location of the γ-ray emission region. This is done self-consistently with parameters inferred from the shape of the spectral energy distribution (SED) in a single-zone leptonic EC-BLR model scenario. We take into account all geometrical effects both in the calculation of the γγ opacity and the normalization of the BLR radiation energy density. As specific examples, we study the FSRQs 3C279 and PKS 1510-089, keeping the BLR radiation energy density at the location of the emission region fixed at the values inferred from the SED. We confirm previous findings that the optical depth due to γγ absorption in the BLR radiation field exceeds unity for both 3C279 and PKS 1510-089 for locations of the γ-ray emission region inside the inner boundary of the BLR. It decreases monotonically, with distance from the central engine and drops below unity for locations within the BLR. For locations outside the BLR, the BLR radiation energy density required for the production of GeV γ-rays rapidly increases beyond observational constraints, thus making the EC-BLR mechanism implausible. Therefore, in order to avoid significant γγ absorption by the BLR radiation field, the γ-ray emission region must therefore be located near the outer boundary of the BLR.

  3. The Kinematics, Physical Condition and Magnetic Field of the W3 Irs5 Region

    NASA Astrophysics Data System (ADS)

    Imai, Hiroshi; Sarma, Anuj P.

    2005-01-01

    We have independently investigated water masers associated with the star-forming region W3 IRS5 with the VLBA. Imai et al., found that the maser 3-D motions exhibit outflows, which likely originate from two of the hyper-compact HII regions in this source. Sarma et al., have detected the Zeeman effect in water masers toward W3 IRS5 and measured line-of-sight magnetic field strengths of between 14 and 42 mG. The directions of maser linear polarization are well aligned in the whole maser region and perpendicular to the estimated magnetic field. These polarimetric results are consistent with an hourglass model of the magnetic field in W3 IRS5. Imai et al., also have analyzed the microstructures found in the individual maser features (˜1AU), which exhibit the "fractal fashion" and express turbulence on very small scales. Together, we have demonstrated that observations of water masers enable us to comprehensively enhance our understanding of the early stages of the formation of massive stars in clusters.

  4. The Kinematics, Physical Condition and Magnetic Field of the W3 IRS5 Region

    NASA Astrophysics Data System (ADS)

    Imai, Hiroshi; Sarma, Anuj P.

    We have independently investigated water masers associated with the star-forming region W3 IRS5 with the VLBA. Imai et al., found that the maser 3-D motions exhibit outflows, which likely originate from two of the hyper-compact HII regions in this source. Sarma et al., have detected the Zeeman effect in water masers toward W3 IRS5 and measured line-of-sight magnetic field strengths of between 14 and 42 mG. The directions of maser linear polarization are well aligned in the whole maser region and perpendicular to the estimated magnetic field. These polarimetric results are consistent with an hourglass model of the magnetic field in W3 IRS5. Imai et al., also have analyzed the microstructures found in the individual maser features (˜1AU), which exhibit the "fractal fashion" and express turbulence on very small scales. Together, we have demonstrated that observations of water masers enable us to comprehensively enhance our understanding of the early stages of the formation of massive stars in clusters.

  5. An improved permanent magnet quadrupole design with larger good field region for high intensity proton linacs

    NASA Astrophysics Data System (ADS)

    Mathew, Jose V.; Rao, S. V. L. S.; Krishnagopal, S.; Singh, P.

    2013-11-01

    The Low Energy High Intensity Proton Accelerator (LEHIPA), being developed at the Bhabha Atomic Research Centre (BARC) will produce a 20 MeV, 30 mA, continuous wave (CW) proton beam. At these low velocities, space-charge forces dominate, and could lead to larger beam sizes and beam halos. Hence in the design of the focusing lattice of the LEHIPA drift tube linac (DTL) using permanent magnet quadrupoles (PMQs), a larger good field region is preferred. Here we study, using the two dimensional (2D) and three dimensional (3D) simulation codes PANDIRA and RADIA, four different types of cylindrical PMQ designs: 16-segment trapezoidal Halbach configuration, bullet-nosed geometry and 8- and 16-segment rectangular geometries. The trapezoidal Halbach geometry is used in a variety of accelerators since it provides very high field gradients in small bores, while the bullet-nosed geometry, which is a combination of the trapezoidal and rectangular designs, is used in some DTLs. This study shows that a larger good field region is possible in the 16-segment rectangular design as compared to the Halbach and bullet-nosed designs, making it more attractive for high-intensity proton linacs. An improvement in good-field region by ˜16% over the Halbach design is obtained in the optimized 16-segment rectangular design, although the field gradient is lower by ˜20%. Tolerance studies show that the rectangular segment PMQ design is substantially less sensitive to the easy axis orientation errors and hence will be a better choice for DTLs.

  6. DeepCNF-D: Predicting Protein Order/Disorder Regions by Weighted Deep Convolutional Neural Fields

    PubMed Central

    Wang, Sheng; Weng, Shunyan; Ma, Jianzhu; Tang, Qingming

    2015-01-01

    Intrinsically disordered proteins or protein regions are involved in key biological processes including regulation of transcription, signal transduction, and alternative splicing. Accurately predicting order/disorder regions ab initio from the protein sequence is a prerequisite step for further analysis of functions and mechanisms for these disordered regions. This work presents a learning method, weighted DeepCNF (Deep Convolutional Neural Fields), to improve the accuracy of order/disorder prediction by exploiting the long-range sequential information and the interdependency between adjacent order/disorder labels and by assigning different weights for each label during training and prediction to solve the label imbalance issue. Evaluated by the CASP9 and CASP10 targets, our method obtains 0.855 and 0.898 AUC values, which are higher than the state-of-the-art single ab initio predictors. PMID:26230689

  7. Interplanetary magnetic field and solar cycle dependence of Northern Hemisphere F region joule heating

    NASA Astrophysics Data System (ADS)

    Bjoland, L. M.; Chen, X.; Jin, Y.; Reimer, A. S.; Skjæveland, Å.; Wessel, M. R.; Burchill, J. K.; Clausen, L. B. N.; Haaland, S. E.; McWilliams, K. A.

    2015-02-01

    Joule heating in the ionosphere takes place through collisions between ions and neutrals. Statistical maps of F region Joule heating in the Northern Hemisphere polar ionosphere are derived from satellite measurements of thermospheric wind and radar measurements of ionospheric ion convection. Persistent mesoscale heating is observed near postnoon and postmidnight magnetic local time and centered around 70° magnetic latitude in regions of strong relative ion and neutral drift. The magnitude of the Joule heating is found to be largest during solar maximum and for a southeast oriented interplanetary magnetic field. These conditions are consistent with stronger ion convection producing a larger relative flow between ions and neutrals. The global-scale Joule heating maps quantify persistent (in location) regions of heating that may be used to provide a broader context compared to small-scale studies of the coupling between the thermosphere and ionosphere.

  8. Orientation of hatchling loggerhead sea turtles to regional magnetic fields along a transoceanic migratory pathway.

    PubMed

    Fuxjager, Matthew J; Eastwood, Brian S; Lohmann, Kenneth J

    2011-08-01

    Young loggerhead sea turtles (Caretta caretta) from the east coast of Florida, USA, undertake a transoceanic migration around the North Atlantic Gyre, the circular current system that flows around the Sargasso Sea. Previous experiments indicated that loggerhead hatchlings, when exposed to magnetic fields replicating those that exist at five widely separated locations along the migratory pathway, responded by swimming in directions that would, in each case, help turtles remain in the gyre and advance along the migratory route. In this study, hatchlings were exposed to several additional magnetic fields that exist along or outside of the gyre's northern boundary. Hatchlings responded to fields that exist within the gyre currents by swimming in directions consistent with their migratory route at each location, whereas turtles exposed to a field that exists north of the gyre had an orientation that was statistically indistinguishable from random. These results are consistent with the hypothesis that loggerhead turtles entering the sea for the first time possess a navigational system in which a series of regional magnetic fields sequentially trigger orientation responses that help steer turtles along the migratory route. By contrast, hatchlings may fail to respond to fields that exist in locations beyond the turtles' normal geographic range. PMID:21753042

  9. On the Dependence of the Ionospheric E-Region Electric Field of the Solar Activity

    NASA Astrophysics Data System (ADS)

    Denardini, Clezio Marcos; Schuch, Nelson Jorge; Moro, Juliano; Araujo Resende, Laysa Cristina; Chen, Sony Su; Costa, D. Joaquim

    2016-07-01

    We have being studying the zonal and vertical E region electric field components inferred from the Doppler shifts of type 2 echoes (gradient drift irregularities) detected with the 50 MHz backscatter coherent (RESCO) radar set at Sao Luis, Brazil (SLZ, 2.3° S, 44.2° W) during the solar cycle 24. In this report we present the dependence of the vertical and zonal components of this electric field with the solar activity, based on the solar flux F10.7. For this study we consider the geomagnetically quiet days only (Kp <= 3+). A magnetic field-aligned-integrated conductivity model was developed for proving the conductivities, using the IRI-2007, the MISIS-2000 and the IGRF-11 models as input parameters for ionosphere, neutral atmosphere and Earth magnetic field, respectively. The ion-neutron collision frequencies of all the species are combined through the momentum transfer collision frequency equation. The mean zonal component of the electric field, which normally ranged from 0.19 to 0.35 mV/m between the 8 and 18 h (LT) in the Brazilian sector, show a small dependency with the solar activity. Whereas, the mean vertical component of the electric field, which normally ranges from 4.65 to 10.12 mV/m, highlight the more pronounced dependency of the solar flux.

  10. The diffracted sound field from the transition region of an axisymmetric body in water

    NASA Astrophysics Data System (ADS)

    Li, Xue-Gang; Yang, Kun-De; Wang, Yong

    2011-07-01

    Understanding the physical features of the diffracted sound field on the surface of an axisymmetric body is important for predicting the self-noise of a sonar mounted on an underwater platform. The diffracted sound field from the transition region of an axisymmetric body was calculated by the geometrical theory of diffraction. The diffraction ray between the source point and the receiving point on the surface of an axisymmetric body was calculated by using the dynamic programming method. Based on the diffracted sound field, a simulation scheme for the noise correlation of the conformal array was presented. It was shown that the normalized pressure of the diffracted sound field from the transition region reduced with the increases of the frequency and the curvature of the ray. The flow noises of two models were compared and a rather optimum fore-body geometric shape was given. Furthermore, it was shown that the correlation of the flow noise in the low frequencies was stronger than that in the high frequencies. And the flow noise received by the acoustic array on the curved surface had a stronger correlation than that on the head plane at the designed center frequency, which is important for sonar system design.

  11. Distribution of the Crustal Magnetic Field in Sichuan-Yunnan Region, Southwest China

    PubMed Central

    Bai, Chunhua; Kang, Guofa; Gao, Guoming

    2014-01-01

    Based on the new and higher degree geomagnetic model NGDC-720-V3, we have investigated the spatial distribution, the altitude decay characteristics of the crustal magnetic anomaly, the contributions from different wavelength bands to the anomaly, and the relationship among the anomaly, the geological structure, and the geophysical field in Sichuan-Yunnan region of China. It is noted that the most outstanding feature in this area is the strong positive magnetic anomaly in Sichuan Basin, a geologically stable block. Contrasting with this feature, a strong negative anomaly can be seen nearby in Longmen Mountain block, an active block. This contradiction implies a possible relationship between the magnetic field and the geological activity. Completely different feature in magnetic field distribution is seen in the central Yunnan block, another active region, where positive and negative anomalies distribute alternatively, showing a complex magnetic anomaly map. Some fault belts, such as the Longmen Mountain fault, Lijiang-Xiaojinhe fault, and the Red River fault, are the transitional zones of strong and weak or negative and positive anomalies. The corresponding relationship between the magnetic anomaly and the geophysical fields was confirmed. PMID:25243232

  12. Observations of the longitudinal magnetic field in the transition region and photosphere of a sunspot

    NASA Technical Reports Server (NTRS)

    Henze, W., Jr.; Tandberg-Hanssen, E.; Hagyard, M. J.; West, E. A.; Woodgate, B. E.; Shine, R. A.; Beckers, J. M.; Bruner, M.; Hyder, C. L.; West, E. A.

    1982-01-01

    The Ultraviolet Spectrometer and Polarimeter on the Solar Maximum Mission spacraft has observed for the first time the longitudinal component of the magnetic field by means of the Zeeman effect in the transition region above a sunspot. The data presented here were obtained on three days in one sunspot, have spatial resolutions of 10 arcsec and 3 arcsec, and yield maximum field strengths greater than 1000 G above the umbrae in the spot. The method of analysis, including a line-width calibration feature used during some of the observations, is described in some detail in an appendix; the line width is required for the determination of the longitudinal magnetic field from the observed circular polarization. The transition region data for one day are compared with photospheric magnetograms from the Marshall Space Flight Center. Vertical gradients of the magnetic field are compared from the two sets of data; the maximum gradients of 0.41 to 0.62 G/km occur above the umbra and agree with or are smaller than values observed previously in the photosphere and low chromosphere.

  13. Focus and enlarge the enhancement region of local electric field by overlapping Ag triangular nanoplates

    NASA Astrophysics Data System (ADS)

    Zhang, Chun-Hong; Zhu, Jian; Li, Jian-Jun; Zhao, Jun-Wu

    2016-01-01

    The local electric field enhancements of overlapping Ag triangular nanoplates are investigated using the discrete dipole approximate (DDA) method. The enhancement region of local electric field in the gap could be focused and enlarged by adjusting the thickness and the number of layers of the nanoplates. For the double-layer Ag triangular nanoplates, with the thickness increasing, the electric field enhancements transform from near the corners to the center of the gap gradually and the intensities get stronger. The largest "hot spot volume" appears as the thickness increases to 20 nm. The plasmonic coupling between the two nanoplates leads to the surface charges accumulating on the surfaces adjoining the gap. The variation of the surface charges due to the increase of the thickness should be responsible for this phenomenon. For the multilayer Ag triangular nanoplates, the enhancement region enlarges as the number of layers increases. And the "hot spot volume" could reach about 72% of the total volume of the middle gap when the number of layers is 6. The large volume of the intense electric field enhancements obtained in overlapping Ag triangular nanoplates provide potential for surface-enhanced Raman scattering (SERS) and surface enhancement fluorescence (SEF) applications. Figures s1-4 are available in electronic form only at http://www.epjap.org

  14. Bias Corrections for Regional Estimates of the Time-averaged Geomagnetic Field

    NASA Astrophysics Data System (ADS)

    Constable, C.; Johnson, C. L.

    2009-05-01

    We assess two sources of bias in the time-averaged geomagnetic field (TAF) and paleosecular variation (PSV): inadequate temporal sampling, and the use of unit vectors in deriving temporal averages of the regional geomagnetic field. For the first temporal sampling question we use statistical resampling of existing data sets to minimize and correct for bias arising from uneven temporal sampling in studies of the time- averaged geomagnetic field (TAF) and its paleosecular variation (PSV). The techniques are illustrated using data derived from Hawaiian lava flows for 0-5~Ma: directional observations are an updated version of a previously published compilation of paleomagnetic directional data centered on ± 20° latitude by Lawrence et al./(2006); intensity data are drawn from Tauxe & Yamazaki, (2007). We conclude that poor temporal sampling can produce biased estimates of TAF and PSV, and resampling to appropriate statistical distribution of ages reduces this bias. We suggest that similar resampling should be attempted as a bias correction for all regional paleomagnetic data to be used in TAF and PSV modeling. The second potential source of bias is the use of directional data in place of full vector data to estimate the average field. This is investigated for the full vector subset of the updated Hawaiian data set. Lawrence, K.P., C.G. Constable, and C.L. Johnson, 2006, Geochem. Geophys. Geosyst., 7, Q07007, DOI 10.1029/2005GC001181. Tauxe, L., & Yamazkai, 2007, Treatise on Geophysics,5, Geomagnetism, Elsevier, Amsterdam, Chapter 13,p509

  15. Regional electric field induced by electroconvulsive therapy: a finite element simulation study.

    PubMed

    Lee, Won Hee; Deng, Zhi-De; Kim, Tae-Seong; Laine, Andrew F; Lisanby, Sarah H; Peterchev, Angel V

    2010-01-01

    The goal of this study is to investigate the regional distribution of the electric field (E-field) strength induced by electroconvulsive therapy (ECT), and to contrast clinically relevant electrode configurations through finite element (FE) analysis. An FE human head model incorporating tissue heterogeneity and white matter anisotropy was generated based on structural magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI) data. We simulated the E-field spatial distributions of three standard ECT electrode placements [bilateral (BL), bifrontal (BF), and right unilateral (RUL)] and an investigational electrode configuration [focal electrically administered seizure therapy (FEAST)]. A quantitative comparison of the E-field strength was subsequently carried out in various brain regions of interests (ROIs) that have putative role in the therapeutic action and/or adverse side effects of ECT. This study illustrates how the realistic FE head model provides quantitative insight in the biophysics of ECT, which may shed light on the differential clinical outcomes seen with various forms of ECT, and may guide the development of novel stimulation paradigms with improved risk/benefit ratio. PMID:21096148

  16. Simulation of the low latitude ionosphere response to disturbed winds and electric fields: Brazilian region

    NASA Astrophysics Data System (ADS)

    Batista, Inez S.; Souza, Jonas; Bailey, Graham; Bravo, Manuel

    2016-07-01

    Modeling the ionosphere during disturbed periods is one of the most challenging tasks due to the complexity of the phenomena that affect the electric fields and the thermosphere environment as whole. It is well known that depending on the direction of the interplanetary magnetic field disturbance electric fields (undershielding or overshielding) can penetrate from high to low latitudes causing significant disturbances in the electron density distribution and in the equatorial ionization anomaly (EIA) development. Besides that, the large amount of energy deposited in the polar region during disturbed periods will be responsible for the generation of disturbed winds that will flow towards the equator where they produce a disturbance dynamo which also affects the EIA density distribution. The TIDs and TADs are also sources of disturbances that propagate at high velocity reaching the equator 2-3 hours after the beginning of the magnetic storm. In this work we use the Sheffield University Plasmasphere-Ionosphere Model at INPE (SUPIM-INPE), to simulate the drastic effects that were observed at the low latitude ionosphere in the Brazilian region during a very intense magnetic storm event. A few models are tested for the disturbed electric field and wind. The simulation results showed that the observations are better explained when considering a traveling waveform disturbance propagating from north to south at a velocity equal to 200 m/s.

  17. Rocket-borne particle, field, and plasma observations in the cleft region. [ionospheric sounding

    NASA Technical Reports Server (NTRS)

    Ungstrup, E.; Bahnsen, A.; Olesen, J. K.; Primdahl, F.; Spangslev, F.; Heikkila, W. J.; Klumpar, D. M.; Winningham, J. D.; Fahleson, U.; Falthammar, C.-G.

    1975-01-01

    Results are reported for comprehensive observations of magnetic and electric fields together with ambient and suprathermal plasmas above the dayside auroral oval with rocket-borne instrumentation which penetrated the cleft region. Measurements were also obtained equatorward and poleward of the cleft. Convection velocities as inferred from electric-field measurements were generally toward noon equatorward of the cleft and were antisunward over the polar cap. Observations of electron temperatures, electric fields, and low-frequency electrostatic noise provide strong evidence of a plasma instability (Farley-Buneman) in the E-layer associated with the appearance of the 'slant E condition' identified in ground-acquired ionograms. The positions of these measurements relative to that of the cleft were firmly established via the determination of the plasma environment with an electrostatic analyzer.

  18. Generation of propagating spin waves from regions of increased dynamic demagnetising field near magnetic antidots

    SciTech Connect

    Davies, C. S. Kruglyak, V. V.; Sadovnikov, A. V.; Nikitov, S. A.; Grishin, S. V.; Sharaevskii, Yu. P.

    2015-10-19

    We have used Brillouin Light Scattering and micromagnetic simulations to demonstrate a point-like source of spin waves created by the inherently nonuniform internal magnetic field in the vicinity of an isolated antidot formed in a continuous film of yttrium-iron-garnet. The field nonuniformity ensures that only well-defined regions near the antidot respond in resonance to a continuous excitation of the entire sample with a harmonic microwave field. The resonantly excited parts of the sample then served as reconfigurable sources of spin waves propagating (across the considered sample) in the form of caustic beams. Our findings are relevant to further development of magnonic circuits, in which point-like spin wave stimuli could be required, and as a building block for interpretation of spin wave behavior in magnonic crystals formed by antidot arrays.

  19. Validation of GOCE global gravitational field models by comparison with regional geoid and gravity anomaly surfaces

    NASA Astrophysics Data System (ADS)

    Sprlak, M.; Gerlach, C.; Pettersen, B. R.; Omang, O. C. D.

    2012-04-01

    The satellite gravitational gradiometry mission GOCE provides various products related to the Earth's gravitational field. One of these products is a global gravitational field model, i.e. representation of the Earth's gravitational field in terms of spherical harmonic coefficients. Such a model is used in realizing vertical reference frames in geodesy, exploring the interior of the Earth in geophysics and geology, studying the behavior of currents in oceanography, or discovering sea level rise and ice-melting in climatology. Numerous Earth's gravitational field representations have already been derived from GOCE. These representations differ according to the time span of GOCE measurements and the theoretical approach used in the harmonic analysis. To assess the quality of the GOCE models validation by independent knowledge of the gravitational field has to be performed. Global gravitational field models with limited spectral/spatial resolution are validated by terrestrial data. In this case, spectral inconsistency between the two sources of data has to be treated properly. An intuitive approach to perform the validation in a consistent way is offered by an adequate filtering. Transformation of the regional data into the spectral domain is performed firstly. Then a low-pass filter is applied to generate a smoothed version of the regional model with the same spectral content as the global GOCE model. Subsequently, the filtered signal is transformed back into the space domain where comparison with a GOCE geoid surface is performed. Despite its conceptual simplicity, the development of an optimal filtering procedure is still challenging. In this contribution we address some aspects of the filtering method. Firstly, a simulation study based on EGM2008 is performed to investigate the accuracy of the direct transformation from space to frequency domain and its inverse. Moreover, various mathematical filters are considered to filter out the short wavelengths. Secondly

  20. Magnetic field in Photodissociation Regions (PDRs) : A case study of PDR in NGC 2024

    NASA Astrophysics Data System (ADS)

    Anish Roshi, D.; Goss, Miller; Jeyakumar, S.

    2015-01-01

    We present images of C110α and H110α radio recombination line (RRL) emission at 4.8 GHz and images of H166α, C166α and X166α RRL emission at 1.4 GHz, observed toward the starforming region NGC 2024. The 1.4 GHz image with angular resolution ˜ 70 arcsec is obtained using VLA data. The 4.8 GHz image with angular resolution ˜ 17 arcsec is obtained by combining VLA and GBT data. These images reveal that the spatial distributions of C110α line emission is confined to the southern rim of the HII region close to the ionization front whereas the C166α line emission is extended in the north-south direction across the HII region. The LSR velocity of the C110α line is 10.3 kms similar to that of lines observed from molecular material located at the far side of the HII region. This similarity suggests that the photo dissociation region (PDR) responsible for C110α line emission is at the far side of the HII region. The LSR velocity of C166α is 8.8 kms. This velocity is comparable with the velocity of molecular absorption lines observed from the foreground gas, suggesting that the PDR is at the near side of the HII region. Non-LTE models for carbon line forming regions are presented. Typical properties of the foreground PDR are T_{PDR} ˜ 100 K, n_e^{PDR} ˜ 5 \\cm3, n_H ˜ 1.7 × 10^4 \\cm3, path length l ˜ 0.06 pc and those of the far side PDR are T_{PDR} ˜ 200 K, n_e^{PDR} ˜ 50 \\cm3, n_H ˜ 1.7 × 10^5 \\cm3, l ˜ 0.03 pc. Our modeling indicates that the far side PDR is located within the HII region. Using the method proposed by Roshi (2007), we estimate magnetic field strength in the foreground PDR to be 60 μG and that in the far side PDR to be 220 μG. Our field estimates compare well with the values obtained from OH Zeeman observations toward NGC 2024.

  1. Structure and Stability of Magnetic Fields in Solar Active Region 12192 Based on the Nonlinear Force-free Field Modeling

    NASA Astrophysics Data System (ADS)

    Inoue, S.; Hayashi, K.; Kusano, K.

    2016-02-01

    We analyze a three-dimensional (3D) magnetic structure and its stability in large solar active region (AR) 12192, using the 3D coronal magnetic field constructed under a nonlinear force-free field (NLFFF) approximation. In particular, we focus on the magnetic structure that produced an X3.1-class flare, which is one of the X-class flares observed in AR 12192. According to our analysis, the AR contains a multiple-flux-tube system, e.g., a large flux tube, with footpoints that are anchored to the large bipole field, under which other tubes exist close to a polarity inversion line (PIL). These various flux tubes of different sizes and shapes coexist there. In particular, the latter are embedded along the PIL, which produces a favorable shape for the tether-cutting reconnection and is related to the X-class solar flare. We further found that most of magnetic twists are not released even after the flare, which is consistent with the fact that no observational evidence for major eruptions was found. On the other hand, the upper part of the flux tube is beyond a critical decay index, essential for the excitation of torus instability before the flare, even though no coronal mass ejections were observed. We discuss the stability of the complicated flux tube system and suggest the reason for the existence of the stable flux tube. In addition, we further point out a possibility for tracing the shape of flare ribbons, on the basis of a detailed structural analysis of the NLFFF before a flare.

  2. [Spatial variability and management zone of soil major nutrients in tobacco fields in Qiannan mountainous region].

    PubMed

    Wu, De-Chuan; Luo, Hong-Xiang; Song, Ze-Min; Guo, Guang-Dong; Chen, Yong-An; Li, Yu-Xiang; Jiang, Yu-Ping; Li, Zhang-Hai

    2014-06-01

    Spatial variability and management zone of soil major nutrients in tobacco fields in Qian-nan mountainous region were analyzed using geostatistics and fuzzy c-mean algorithm. Results indicated that the level of soil organic matter (OM) was moderate, and alkalytic nitrogen (AN), available phosphorus (AP) and available potassium (AK) were rich according to tobacco soil nutrient classification standards. Coefficients of variation (CV) of OM, AN, AP and AK were moderate. Contents of OM, AN, AP and AK fitted log-normal distributions. Correlation analysis showed moderate correlations between OM and AN, AP and AK. OM and AN were best described by Gaussian semivariogram models, while AP and AK were described by exponential models. The four nutrients displayed moderate spatial autocorrelation. There were significant differences among lag distances of four soil nutrients. OM, AN, AP and AK in the majority of studied regions varied at moderate to very rich levels, and deficiencies of OM, AN, AP and AK only accounted for 0.93%, 0.53%, 0.24% and 7.91% of the total studied region, respectively. Based on the results, the studied region was divided into two management zones (MZ), namely MZ1 and MZ2, accounting for 69. 8% and 30. 2% of the studied region respectively. The soil levels of OM, AN, AP and AK in MZ1 were significantly lower than those in MZ2 (P < 0.01). PMID:25223027

  3. Properties of magnetic field fluctuations in boundary regions of the Earth's magnetosphere

    NASA Astrophysics Data System (ADS)

    Kozak, Liudmyla; Savin, Sergey; Lui, Anthony Tat Yin; Igor, Gala

    Statistical properties of magnetic field fluctuations in boundary regions of the Earth’s magnetosphere at different timescales were considered. Data with high resolution (22,5 Hz) obtained by Cluster mission from 2004 to 2010 were used. As a characteristic of the fluctuations on various time scales, changes in the shape and parameters of the probability density function and wave analysis were studied. In order for investigations of features of the probability density functions of magnetic field fluctuations we analyzed the statistical properties of the absolute value of magnetic field variations in the different regions of near earth space. Amplitude of fluctuations in the magnetosheath just after crossing bow shock exceeds in a few time amplitude of fluctuations for non-perturbed solar wind or the foreshock. The analysis of the height of maximum of the probability density functions and of the kurtosis values have shown the presence of different asymptotic modes which are characterized by different power laws. The use of the technique of probability density function for magnetic fluctuations has shown that at high frequencies the structure of turbulence differs from that in the low-frequency region. The critical scale corresponds to the scales of the Larmor radius of ions. The research of the statistical properties of boundary layers allows to determine the role of turbulent processes in the interaction of plasma flows with the magnetic obstacles, whether these are fields of planets, stars, or laboratory traps, and to reveal the actual mechanisms of the energy transformation in collisionless plasma. The work is done in the frame of complex program of NAS of Ukraine on space researches for 2012-1016, within the framework of the educational program No.2201250 “Education, Training of students, PhD students, scientific and pedagogical staff abroad” launched by the Ministry of Education and Science of Ukraine and under a partial support of the grant No. F 53.2/039.

  4. Singular surfaces in the open field line region of a diverted tokamak

    SciTech Connect

    Reiman, A.

    1995-05-01

    The structure of the open field lines of a slightly nonaxisymmetric, poloidally diverted tokamak is explored by numerical integration of the field line equations for a simple model field. In practice, the nonaxisymmetry could be produced self-consistently by the nonlinear evolution of a free-boundary MHD mode, or it could be produced by field errors, or it could be imposed externally by design. In the presence of a nonaxisymmetric perturbation, the tokamak is shown to develop open field line regions of differing topology separated by singular surfaces. It is argued that the singular surfaces can be expected to play a role analogous to that of rational toroidal flux surfaces, in terms of constraining ideal MHD perturbations and thus constraining the free-energy that can be tapped by ideal MHD instabilities. The possibility of active control of free-boundary instabilities by means of currents driven on the open singular surfaces, which are directly accessible from the divertor plates, is discussed. Also discussed is the possibility of early detection of imminent disruptions through localized measurement of the singular surface currents.

  5. Regional jointing and hydrocarbon generation in Big Sandy gas field, Kentucky

    SciTech Connect

    Loar, S.J.

    1986-05-01

    Producing wells in the Big Sandy gas field depend on well-developed subsurface joint systems to enhance migration into the borehole. To examine the joint systems, the surface joints were studied. Statistical analysis revealed eight regional joint sets: N30/sup 0/W, N10/sup 0/W, N20/sup 0/E, N30/sup 0/E, N40/sup 0/E, N60/sup 0/E, N80/sup 0/E, and east-west. These sets have the same orientations as reservoir joints observed in oriented cores, indicating that they are part of the same systems. Field observations suggest that the regional joint sets formed in at least three phases, which can be classified as hydraulic, tectonic, and unloading. The timing of hydrocarbons was calculated from a subsidence curve for Devonian and younger formations, which was constructed on the basis of published isopach, conodont alteration index, and well data. Plotting the maturation of the Ohio Shale with the regional jointing phases shows that the hydraulic joint sets formed before hydrocarbon generation began, and that the tectonic joint sets formed while the Ohio Shale was in the oil window. The oil and wet gas generated from the Ohio Shale have since migrated through the subsurface joint systems into younger reservoirs.

  6. A new nanoscale fin field effect transistor with embedded intrinsic region for high temperature applications

    NASA Astrophysics Data System (ADS)

    Karimi, Fa.; Orouji, Ali A.

    2016-08-01

    The present paper reveals a novel structure of nanoscale Silicon-On-Insulator (SOI) Fin Field Effect Transistor (FinFET) in which an intrinsic region (EIR) is embedded into the buried oxide layer. The key idea in this work is to improve the critical thermal problems raised by the self-heating effect (SHE). The EIR-FinFET device has lower thermal resistance, reduced hot carrier effect, lower threshold voltage roll-off, and lower critical electric field in comparison with the C-FinFET. Also, higher DC transconductance, lower DC conductance and a better gate capacitance are obtained because the intrinsic region is embedded in a suitable place. Moreover, the simulation result with three-dimensional and two-carrier device simulator demonstrates an improved output characteristic of the proposed structure due to the reduced self-heating effect. The intrinsic silicon layer is located under the source and fin regions and provides more space to dissipate the accumulated heat. Due to the high thermal conductivity of the silicon and decreasing corner effects there, the heat will flow easily and the lattice temperature will decrease. All the extracted results attempt to show the superiority of the EIR-FinFET device over the conventional one, and its effect on the operation of nanoscale low power and high speed devices.

  7. Development of Active Regions: Flows, Magnetic-Field Patterns and Bordering Effect

    NASA Astrophysics Data System (ADS)

    Getling, A. V.; Ishikawa, R.; Buchnev, A. A.

    2016-02-01

    A qualitative analysis is given of the data on the full magnetic and velocity vector fields in a growing sunspot group, recorded nearly simultaneously with the Solar Optical Telescope on the Hinode satellite. Observations of a young bipolar subregion developing within AR 11313 were carried out on 9 - 10 October 2011. Our aim was to form an idea about the consistency of the observed pattern with the well-known rising-tube model of the formation of bipolar active regions and sunspot groups. We find from our magnetograms that the distributions of the vertical [Bv] and the horizontal [Bh] component of the magnetic field over the area of the magnetic subregion are spatially well correlated; in contrast, the rise of a flux-tube loop would result in a qualitatively different pattern, with the maxima of the two magnetic-field components spatially separated: the vertical field would be the strongest where either spot emerges, while the maximum horizontal-field strengths would be reached in between them. A specific feature, which we call the bordering effect, is revealed: some local extrema of Bv are bordered with areas of locally enhanced Bh. This effect suggests a fountainlike spatial structure of the magnetic field near the Bv extrema, which is also hardly compatible with the emergence of a flux-tube loop. The vertical-velocity field in the area of the developing active subregion does not exhibit any upflow on the scale of the whole subregion, which should be related to the rising-tube process. Thus, our observational data can hardly be interpreted in the framework of the rising-tube model.

  8. Details of out-field regional recurrence after involved-field irradiation with concurrent chemotherapy for locally advanced esophageal squamous cell carcinoma

    PubMed Central

    Zhang, Xiaoli; Yu, Jinming; Li, Minghuan; Zhu, Hui

    2016-01-01

    Background The purpose of this study was to describe the patterns of out-field regional recurrence after involved-field irradiation (IFI) in definitive concurrent chemoradiotherapy (CCRT) for locally advanced esophageal squamous cell carcinoma (LA-ESCC) and identify the possible risk factors. Patients and methods Eighty patients with LA-ESCC who received CCRT with IFI between January 2003 and January 2009 at the Shandong Cancer Hospital were recruited and analyzed. Imaging scans demonstrating first sites of failure were compared with original computed tomography-based radiation treatment plans, and failure patterns were defined as in-field, outfield regional (failures in initially uninvolved regional nodes), and distant failures. Results After a median follow-up time of 52.6 months, 24 patients had evidence of out-field regional failure, 43 patients had evidence of in-field failure, and 33 patients had the evidence of distant failure. Multivariate analysis revealed that out-field regional failure was associated with clinical tumor status (T4 vs T1–3, odds ratio [OR] =6.547, P=0.002), tumor length (>8 cm vs ≤8 cm, OR =4.130, P=0.036), response to CCRT (complete response vs no complete response, OR =2.646, P=0.035), and in-field failure (no in-field failure vs in-field failure, OR =1.32, P=0.016). Survival analyses indicated that, compared to in-field failure or distant failure alone group, out-field regional failure alone group tended to have longer overall (P=0.006) and progression-free survival (P=0.164). Conclusion Our data suggested that the predominant failure pattern after IFI was not out-field regional failure, which also did not influence survival significantly, and that out-field regional failure did not shorten the time to disease recurrence, which also did not influence survival significantly. In addition, out-field regional failure was likely to appear later than in-field and distant failures. The relatively advanced local disease followed by poor

  9. Regional stress field around the Taigu fault zone in Shanxi Province, China

    NASA Astrophysics Data System (ADS)

    Li, Bin; Li, Zihong; Sørensen, Mathilde B.; Løvlie, Reidar; Liu, Liqiang; Atakan, Kuvvet

    2015-12-01

    A comprehensive study on regional stress field around the Taigu fault zone in Shanxi Province, China, was performed in this study. To get a better understanding of the present-day stress status in this area, 31 focal mechanisms of M L ≥3 earthquakes since 1965 were compiled, and the best stress tensor was then inverted based on the database. Additionally, magnetic fabrics along the Taigu fault zone were investigated to get an indication of the regional stress field in the past. Our results show that the present-day stress field around the Taigu fault zone is characterized by astable NW-SE extension with a strike-slip component, consistent with the geological surveys and recent GPS data. Results from magnetic fabrics indicate that the orientations of principal stress axes from magnetic fabrics of sedimentary rocks in Neogene coincide to the orientations of principal stress axes from focal mechanisms. The south segment of the Taigu fault displays more complicated magnetic fabrics and more activity of moderate earthquakes. It is connected with the Mianshan west fault and intersects with NW-SE striking Fenyang fault and the north fault of the Lingshi uplift at the south edge of Taiyuan basin. This may be the area needing more attention in terms of seismic risk along the Taigu fault.

  10. A Review of Magnetic Anomaly Field Data for the Arctic Region: Geological Implications

    NASA Technical Reports Server (NTRS)

    Taylor, Patrick T.; vonFrese, Ralph; Roman, Daniel; Frawley, James J.

    1999-01-01

    Due to its inaccessibility and hostile physical environment remote sensing data, both airborne and satellite measurements, has been the main source of geopotential data over the entire Arctic region. Ubiquitous and significant external fields, however, hinder crustal magnetic field studies. These potential field data have been used to derive tectonic models for the two major tectonic sectors of this region, the Amerasian and Eurasian Basins. The latter is dominated by the Nansen-Gakkel or Mid-Arctic Ocean Ridge and is relatively well known. The origin and nature of the Alpha and Mendeleev Ridges, Chukchi Borderland and Canada Basin of the former are less well known and a subject of controversy. The Lomonosov Ridge divides these large provinces. In this report we will present a summary of the Arctic geopotential anomaly data derived from various sources by various groups in North America and Europe and show how these data help us unravel the last remaining major puzzle of the global plate tectonic framework. While Magnetic anomaly data represent the main focus of this study recently derived satellite gravity data (Laxon and McAdoo, 1998) are playing a major role in Arctic studies.

  11. A Review of Magnetic Anomaly Field Data for the Arctic Region: Geological Implications

    NASA Technical Reports Server (NTRS)

    Taylor, Patrick T.; vonFrese, Ralph; Roman, Daniel; Frawley, James J.

    1999-01-01

    Due to its inaccessibility and hostile physical environment remote sensing data, both airborne and satellite measurements, has been the main source of geopotential data over the entire Arctic region. Ubiquitous and significant external fields, however, hinder crustal magnetic field studies These potential field data have been used to derive tectonic models for the two major tectonic sectors of this region, the Amerasian and Eurasian Basins. The latter is dominated by the Nansen-Gakkel or Mid-Arctic Ocean Ridge and is relatively well known. The origin and nature of the Alpha and Mendeleev Ridges, Chukchi Borderland and Canada Basin of the former are less well known and a subject of controversy. The Lomonosov Ridge divides these large provinces. In this report we will present a summary of the Arctic geopotential anomaly data derived from various sources by various groups in North America and Europe and show how these data help us unravel the last remaining major puzzle of the global plate tectonic framework. While magnetic anomaly data represent the main focus of this study recently derived satellite gravity data are playing a major role in Arctic studies.

  12. Crustal Structure Beneath the Lake Ontario Region from Inverse Models of Potential Field and Seismic Data

    NASA Astrophysics Data System (ADS)

    Navarrete, L. C.; Benoit, M. H.; Ebinger, C. J.; Horowitz, F.

    2014-12-01

    The regions surrounding Lake Ontario (e.g. the Adirondack mountain region and its northern border with Canada) are among the most seismically active regions in the Eastern US. However, only scant knowledge exists of the location and geometry of faults, suture zones, or crustal thickness variations that may localize strain in the crust beneath sections of New York, Pennsylvania and Ontario. Our aim is to determine the crustal density and magnetic susceptibility contrasts (e.g., steep faults, intrusive bodies, Moho topography) which give rise to anomaly patterns and to place constraints on their geometries and locations. With a better understanding of these structures, we will examine how the distribution of the faults and steep contacts throughout the region compare with zones of active seismicity. Utilizing the North American Gravity Database, we created a profile that crosses a narrow Bouguer anomaly with steep gradients surrounded by Bouguer anomaly highs transecting the lake and extending onshore east of Rochester, subparallel to the seismically active Clarendon-Linden fault. Euler deconvolution and 'worm' analyses show that this narrow anomaly is bounded by east-dipping faults that extend to mid-crustal levels. We perform receiver function analyses of Earthscope TA stations in the region in order to constrain crustal thickness and lateral variations in Vp/Vs. These receiver functions at onshore sites in the area show complex Moho structure which partially explains our anomaly.Additionally, a vintage seismic profile coupled with the Lake Ontario bathymetry dataset was used to place constraints on sedimentary strata thicknesses and to identify structures within Proterozoic basement. Predictive models of crustal variations were created from a potential field profile, receiver functions, and a seismic profile to test interpretations. The Moho topography alone does not fully explain the short wavelength gravity anomaly, and a sedimentary basin of 3-5 km in depth is

  13. [Distribution of Regional Pollution and the Characteristics of Vertical Wind Field in the Pearl River Delta].

    PubMed

    Liu, Jian; Wu, Dui; Fan, Shao-jia

    2015-11-01

    Based on the data of hourly PM2.5 concentration of 56 environmental monitoring stations and 9 cities over the Pearl River Delta (PRD) region, the distributions of PM2.5 pollution in PRD region were analyzed by systematic cluster analysis and correlational analysis. It was found that the regional pollution could be divided into 3 types. The first type was the pollution occurred in Dongguan, Guangzhou, Foshan and Jiangmen (I type), and the second type was the pollution occurred in Zhongshan, Zhuhai, Shenzhen and Huizhou (II type), while the last type was the pollution only occurred in Zhaoqing (III type). During the study period, they occurred 47, 7 and 128 days, respectively. During events of pollution type I, except Zhuhai, Shenzhen and Huizhou, the PM2.5 concentrations of other cities were generally high, while the PM2.5 concentration in whole PRD region was over 50.0 μg x m(-3) during events of pollution type II. The regions with higher PM2.5 concentration was mainly concentrated in Zhaoqing, Guangzhou and Foshan during events of pollution type III. The wind data from 4 wind profile radars located in PRD region was used to study the characteristics of vertical wind field of these 3 pollution types. It was found that the wind profiles of type I and III were similar that low layer and high layer were controlled by the southeast wind and the southwest wind, respectively. For type II, the low layer and high layer were influenced by northerly wind and westerly wind, respectively. Compared with other types, the wind speed and ventilation index of type II. were much higher, and the variation of wind direction at lower-middle-layer was much smaller. When PRD region was influenced by northerly winds, the PM2.5 concentration in the entire PRD region was higher. When PRD region was controlled by southeast wind, the PM2.5 concentrations of I and II areas were relatively lower, while the pollution in III area was relatively heavier. PMID:26910982

  14. Simulating Turbulent Wind Fields for Offshore Turbines in Hurricane-Prone Regions (Poster)

    SciTech Connect

    Guo, Y.; Damiani, R.; Musial, W.

    2014-04-01

    Extreme wind load cases are one of the most important external conditions in the design of offshore wind turbines in hurricane prone regions. Furthermore, in these areas, the increase in load with storm return-period is higher than in extra-tropical regions. However, current standards have limited information on the appropriate models to simulate wind loads from hurricanes. This study investigates turbulent wind models for load analysis of offshore wind turbines subjected to hurricane conditions. Suggested extreme wind models in IEC 61400-3 and API/ABS (a widely-used standard in oil and gas industry) are investigated. The present study further examines the wind turbine response subjected to Hurricane wind loads. Three-dimensional wind simulator, TurbSim, is modified to include the API wind model. Wind fields simulated using IEC and API wind models are used for an offshore wind turbine model established in FAST to calculate turbine loads and response.

  15. Chiral effective-field theory in the Delta(1232) region : II. radiative pion photoproduction

    SciTech Connect

    Vladimir Pascalutsa; Marc Vanderhaeghen

    2007-10-12

    We present a theoretical study of the radiative pion photoproduction on the nucleon ($\\gamma N \\rightarrow \\pi N \\gamma'$) in the $\\De$-resonance region, with the aim to determine the magnetic dipole moment (MDM) of the $\\Delta^+(1232)$. The study is done within the framework of chiral effective-field theory where the expansion is performed (to next-to-leading order) in the $\\delta$ power-counting scheme which is an extension of chiral perturbation theory to the $\\Delta$-resonance energy region. We present in detail the results for the absorptive part of the $\\Delta$ MDM, as well as a sensitivity study for the radiative pion photoproduction observables on the real part of the $\\Delta$ MDM. We find that an asymmetry for circular polarization of the photon beam may provide a model-independent way to measure the $\\Delta$ MDM.

  16. Regional hydrology of the Dixie Valley geothermal field, Nevada: preliminary interpretations of chemical and isotopic data

    SciTech Connect

    Counce, D; Dunlap, C; Goff, F; Huebner, M; Janik, C; Johnson, S; Nimz, G

    1999-08-16

    Chemical and isotopic analyses of Dixie Valley regional waters indicate several distinct groups ranging in recharge age from Pleistocene (<20 ka) to recent (<50a). Valley groundwater is older than water from perennial springs and artesian wells in adjacent ranges, with Clan Alpine range (east) much younger (most <50a) than Stillwater range (west; most >1000a). Geothermal field fluids ({approximately}12-14 ka) appear derived from water similar in composition to non-thermal groundwater observed today in valley artesian wells (also -14 ka). Geothermal fluid interaction with mafic rocks (Humboldt Lopolith) appears to be common, and significant reaction with granodiorite may also occur. Despite widespread occurrence of carbonate rocks, large scale chemical interaction appears minor. Age asymmetry of the ranges, more extensive interaction with deep-seated waters in the west, and distribution of springs and artesian wells suggest the existence of a regional upward hydrologic gradient with an axis in proximity to the Stillwater range.

  17. Feasibility Demonstration of Wide-Field Fourier-Spectroscopic-Imaging in Infrared Region

    NASA Astrophysics Data System (ADS)

    Qi, Wei; Takuma, Takashi; Tsutsumi, Ryosuke; Inui, Asuka; Kagiyama, Hiroyasu; Kojima, Daisuke; Nishiyama, Akira; Ishimaru, Ichirou

    We are aiming at the realization of living-environment sensor and non-invasive blood-sugar sensor by the proposed imaging type 2-D Fourier spectroscopy. This method is based on the phase-shift interference between the object beams. As a result, even if the object beams are spatially incoherent, we can observe the phase-shift interference phenomena. In the near infrared region, we can obtain the high-contrast blood vessel image of mouse's ear in the deeper part by InGaAs camera. Furthermore, in the mid-infrared region, we have successfully measured the radiation spectroscopic-imaging with wild field of view by the infrared module, such as the house plants.

  18. Spatial and temporal variation of gravity field in the capital region

    NASA Astrophysics Data System (ADS)

    Hua, Chang-Cai; Guo, Yong; Liu, Duan-Fa; Xiao, Gang; Kuo, J. T.; Brown, Walter

    1995-08-01

    The high accurate gravity measurement have been carried out many years in the capital region. The main characteristics of the change of gravity field during the latest eight years (1981 1988) in the region are presented in this paper. The more gravitational variation appeared in the southern and south-eastern part, the maximum variation come to 10-6 ms-2. In the northern part, for instance: Chengde City, and Wanxian County—west Taihang mountain area which are in the westside of the network, were relative stable. The noticeable areas of gravitational variation were in Tianjin-Baxian-Renqiu which correspond with the crustal vertical deformation. The main cause of that is related to pump ground water and petroleum.

  19. An Experimental Study of the Near Field Region of a Free Jet with Passive Mixing Tabs

    NASA Technical Reports Server (NTRS)

    Bohl, D. G.; Foss, J. F.

    1997-01-01

    An experimental study was performed to determine the flow characteristics of a tabbed free jet. Results were acquired in the near field (nominally 2 tab widths upstream to 2 tab widths downstream of the exit plane) of a tabbed jet. Upstream pressure results showed static pressure distributions in both the x-and y-directions along the top surface of the tunnel. Hot-wire measurements showed rapid expansion of the core fluid into the ambient region. Two counter rotating regions of streamwise vorticity were shown on each side of the primary tab. An enhancement of the tabbed jet concept was proposed and tested. Specifically, two tabs, half the scale of the primary tab, were added to the primary tab to provide attachment surfaces for the normally occurring ejection of fluid. The secondary tabs caused a slight increase in the streamwise vorticity created from the upstream static pressure gradient while significantly increasing the re-oriented boundary layer vorticity. The combined pumping effect of the two counter rotating regions of vorticity caused a significant increase in the transport of the jet core fluid into the surrounding region.

  20. Pulsed-field map of Xq13 in the region of the human X inactivation center

    SciTech Connect

    Lafreniere, R.G.; Willard, H.F. )

    1993-08-01

    The authors have used human/mouse hybrid cell lines to derive a pulsed-field map of the Xq13 region of the human X chromosome, in the vicinity of the X inactivation center (XIC). They have mapped nine loci within two separate clusters (I and II). Cluster I contains three loci (DXS227, XIST, and DXS128) linked within 1700 kb. This cluster also includes the breakpoint of a translocated X;14 chromosome used to define the proximal border of the XIC region. Cluster II covers an additional 1800 kb and physically links six loci (DXS56, DXS171, DXS325, DXS347, DXS356, and DXS441) located between the XIC and the genes for Menkes disease (MNK) and PGK1. Maps of cluster I loci derived from active (X[sub a]) or inactive (X[sub i]) X chromosomes differed, presumably due to methylation differences between the X[sub a] and X[sub i]. This map provides a basis for examining the organization of the Xq13.2-q13.3 region, in the around the XIC, and will assist in the further cloning of expressed sequences from this region. 13 refs., 2 figs., 1 tab.

  1. 30 MHz radar observations of artificial E region field-aligned plasma irregularities

    NASA Astrophysics Data System (ADS)

    Hysell, D. L.

    2008-02-01

    Artificial E region field aligned irregularities (FAIs) have been observed during heating experiments at the HAARP facility using a new 30 MHz coherent scatter radar imager deployed near Homer, Alaska. Irregularities were observed during brief experiments on three quiet days in July and August, 2007, when the daytime E region critical frequency was close to 3 MHz. Irregularities were consistently generated and detected during experiments with O-mode HF pumping on zenith with a 1-min on, 1-min off CW modulation. The scattering cross sections, rise, and fall times of the echoes were observed as well as their spectral properties. Results were found to be mainly in agreement with observations from other mid- and high-latitude sites with some discrepancies. Radar images of the irregularity-filled volume on one case exhibited clear variations in backscatter power and Doppler shift across the volume. The images furthermore show the emergence of a small irregularity-filled region to the south southwest of the main region in the approximate direction of magnetic zenith.

  2. Double gate graphene nanoribbon field effect transistor with single halo pocket in channel region

    NASA Astrophysics Data System (ADS)

    Naderi, Ali

    2016-01-01

    A new structure for graphene nanoribbon field-effect transistors (GNRFETs) is proposed and investigated using quantum simulation with a nonequilibrium Green's function (NEGF) method. Tunneling leakage current and ambipolar conduction are known effects for MOSFET-like GNRFETs. To minimize these issues a novel structure with a simple change of the GNRFETs by using single halo pocket in the intrinsic channel region, "Single Halo GNRFET (SH-GNRFET)", is proposed. An appropriate halo pocket at source side of channel is used to modify potential distribution of the gate region and weaken band to band tunneling (BTBT). In devices with materials like Si in channel region, doping type of halo and source/drain regions are different. But, here, due to the smaller bandgap of graphene, the mentioned doping types should be the same to reduce BTBT. Simulations have shown that in comparison with conventional GNRFET (C-GNRFET), an SH-GNRFET with appropriately halo doping results in a larger ON current (Ion), smaller OFF current (Ioff), a larger ON-OFF current ratio (Ion/Ioff), superior ambipolar characteristics, a reduced power-delay product and lower delay time.

  3. Wide-Field Infrared Survey Explorer Observations of the Evolution of Massive Star-Forming Regions

    NASA Technical Reports Server (NTRS)

    Koenig, X. P.; Leisawitz, D. T.; Benford, D. J.; Rebull, L. M.; Padgett, D. L.; Asslef, R. J.

    2012-01-01

    We present the results of a mid-infrared survey of II outer Galaxy massive star-forming regions and 3 open clusters with data from the Wide-field Infrared Survey Explorer (WISE). Using a newly developed photometric scheme to identify young stellar objects and exclude extragalactic contamination, we have studied the distribution of young stars within each region. These data tend to support the hypothesis that latter generations may be triggered by the interaction of winds and radiation from the first burst of massive star formation with the molecular cloud material leftover from that earlier generation of stars. We dub this process the "fireworks hypothesis" since star formation by this mechanism would proceed rapidly and resemble a burst of fireworks. We have also analyzed small cutout WISE images of the structures around the edges of these massive star-forming regions. We observe large (1-3 pc size) pillar and trunk-like structures of diffuse emission nebulosity tracing excited polycyclic aromatic hydrocarbon molecules and small dust grains at the perimeter of the massive star-forming regions. These structures contain small clusters of emerging Class I and Class II sources, but some are forming only a single to a few new stars.

  4. Wide-Field Infrared Survey Explorer Observations of the Evolution of Massive Star-Forming Regions

    NASA Technical Reports Server (NTRS)

    Koenig, X. P.; Leisawitz, D. T.; Benford, D. J.; Rebull, L. M.; Padgett, D. L.; Assef, R. J.

    2011-01-01

    We present the results of a mid-infrared survey of 11 outer Galaxy massive star-forming regions and 3 open clusters with data from the Wide-field Infrared Survey Explorer (WISE). Using a newly developed photometric scheme to identify young stellar objects and exclude extragalactic contamination, we have studied the distribution of young stars within each region. These data tend to support the hypothesis that latter generations may be triggered by the interaction of winds and radiation from the first burst of massive star formation with the molecular cloud material leftover from that earlier generation of stars.We dub this process the "fireworks hypothesis" since star formation by this mechanism would proceed rapidly and resemble a burst of fireworks.We have also analyzed small cutout WISE images of the structures around the edges of these massive star-forming regions. We observe large (1-3 pc size) pillar and trunk-like structures of diffuse emission nebulosity tracing excited polycyclic aromatic hydrocarbon molecules and small dust grains at the perimeter of the massive star-forming regions. These structures contain small clusters of emerging Class I and Class II sources, but some are forming only a single to a few new stars.

  5. WIDE-FIELD INFRARED SURVEY EXPLORER OBSERVATIONS OF THE EVOLUTION OF MASSIVE STAR-FORMING REGIONS

    SciTech Connect

    Koenig, X. P.; Leisawitz, D. T.; Benford, D. J.; Padgett, D. L.; Rebull, L. M.

    2012-01-10

    We present the results of a mid-infrared survey of 11 outer Galaxy massive star-forming regions and 3 open clusters with data from the Wide-field Infrared Survey Explorer (WISE). Using a newly developed photometric scheme to identify young stellar objects and exclude extragalactic contamination, we have studied the distribution of young stars within each region. These data tend to support the hypothesis that latter generations may be triggered by the interaction of winds and radiation from the first burst of massive star formation with the molecular cloud material leftover from that earlier generation of stars. We dub this process the 'fireworks hypothesis' since star formation by this mechanism would proceed rapidly and resemble a burst of fireworks. We have also analyzed small cutout WISE images of the structures around the edges of these massive star-forming regions. We observe large (1-3 pc size) pillar and trunk-like structures of diffuse emission nebulosity tracing excited polycyclic aromatic hydrocarbon molecules and small dust grains at the perimeter of the massive star-forming regions. These structures contain small clusters of emerging Class I and Class II sources, but some are forming only a single to a few new stars.

  6. Ground Observations of Artificial E Region Field-Aligned Irregularities Over HAARP

    NASA Astrophysics Data System (ADS)

    Nossa, E.; Hysell, D. L.

    2008-12-01

    Heating experiments were performed at HAARP intended to create E region field aligned plasma irregularities (FAIs) at midday in July of 2008 when the critical frequency of the E layer is a maximum. Field-aligned backscatter was observed using a 30 MHz imaging coherent scatter radar located close to Homer, Alaska. Three experiment modes were used, involving 1) heating alternately at zenith and magnetic zenith, 2) heating using triangular power modulation, and 3) heating slightly above and below the second electron gyroharmonic. Strong echoes were observed in all cases. Radar imaging and other diagnostic methods are used to examine the degree to which irregularities can be observed outside the Spitze angle, the possible effects of predonditioning on thermal parametric instability, and the effects of the double resonance on backscatter intensity and irregularity formation.

  7. Crustal stress field in the Greek region inferred from inversion of moment tensor solutions

    NASA Astrophysics Data System (ADS)

    Konstantinou, Konstantinos; Mouslopoulou, Vasiliki; Liang, Wen-Tzong; Heidbach, Oliver; Oncken, Onno; Suppe, John

    2016-04-01

    The Hellenic region is the seismically most active area in Europe, having experienced numerous large magnitude catastrophic earthquakes and associated devastating tsunamis. A means of mitigating these potential hazards is by better understanding the patterns of spatial and temporal deformation of the crust across the Hellenic orogenic system, over timescales that range from individual earthquakes to several tens of years. In this study for the first time we make collective use of the Global CMT (GCMT), Regional CMT (RCMT) and National Observatory of Athens (NOA) moment tensor databases in order to extract focal mechanism solutions that will be used to infer crustal stresses in the Greek region at an unprecedented resolution. We focus on the shallow seismicity within the upper plate (down to 42 km) and select solutions with good waveform fits and well-resolved hypocentral depths. In this way we obtained 1,614 focal mechanism solutions covering western Greece up to southern Albania, central and southern Greece, northern Aegean as well as the subduction trench west and east of Crete. These solutions are used as input to a regional-scale damped stress inversion over a grid whose node spacing is 0.35 degrees for the purpose of recovering the three principal stress axes and the stress ratio R for each node. Several sensitivity tests are performed where parameters such as damping, hypocentral depth, magnitude range are varied, in order to ascertain the robustness of our results. The final stress field model is then compared to the GPS-derived strain field revealing an excellent agreement between the two datasets. Additionally, maximum and minimum stress axes orientations are correlated with the strike and dip of known faults in order to improve our understanding of future fault rupture and corresponding seismic hazard.

  8. Regional frequency analysis conditioned on large-scale atmospheric or oceanic fields

    NASA Astrophysics Data System (ADS)

    Renard, Benjamin; Lall, Upmanu

    2014-12-01

    Many studies report that hydrologic regimes are modulated by large-scale modes of climate variability such as the El Niño Southern Oscillation (ENSO) or the North Atlantic Oscillation (NAO). Climate-informed frequency analysis models have therefore been proposed to condition the distribution of hydrologic variables on climate indices. However, standard climate indices may be poor predictors in some regions. This paper therefore describes a regional frequency analysis framework that conditions the distribution of hydrologic variables directly on atmospheric or oceanic fields, as opposed to predefined climate indices. This framework is based on a two-level probabilistic model describing both climate and hydrologic data. The climate data set (predictor) is typically a time series of atmospheric of oceanic fields defined on a grid over some area, while the hydrologic data set (predictand) is typically a regional data set of station data (e.g., annual average flow at several gauging stations). A Bayesian estimation framework is used, so that a natural quantification of uncertainties affecting hydrologic predictions is available. A case study aimed at predicting the number of autumn flood events in 16 catchments located in Mediterranean France using geopotential heights at 500 hPa over the North-Atlantic region is presented. The temporal variability of hydrologic data is shown to be associated with a particular spatial pattern in the geopotential heights. A cross-validation experiment indicates that the resulting probabilistic climate-informed predictions are skillful: their reliability is acceptable and they are much sharper than predictions based on standard climate indices and baseline predictions that ignore climate information.

  9. Regional frequency analysis conditioned on large-scale atmospheric or oceanic fields

    NASA Astrophysics Data System (ADS)

    Renard, Benjamin; Lall, Upmanu

    2015-04-01

    Many studies report that hydrologic regimes are modulated by large-scale modes of climate variability such as the El Niño Southern Oscillation (ENSO) or the North Atlantic Oscillation (NAO). Climate-informed frequency analysis models have therefore been proposed to condition the distribution of hydrologic variables on climate indices. However, standard climate indices may be poor predictors in some regions. This paper therefore describes a regional frequency analysis framework that conditions the distribution of hydrologic variables directly on atmospheric or oceanic fields, as opposed to predefined climate indices. This framework is based on a 2-level probabilistic model describing both climate and hydrologic data. The climate dataset (predictor) is typically a time series of atmospheric of oceanic fields defined on a grid over some area, while the hydrologic dataset (predictand) is typically a regional dataset of station data (e.g. annual peak flow at several gauging stations). A Bayesian estimation framework is used, so that a natural quantification of uncertainties affecting hydrologic predictions is available. A case study aimed at predicting the number of autumn flood events in 16 catchments located in Mediterranean France using geopotential heights at 500 hPa over the North-Atlantic region is presented. The temporal variability of hydrologic data is shown to be associated with a particular spatial pattern in the geopotential heights. A cross-validation experiment indicates that the resulting probabilistic climate-informed predictions are skillful: their reliability is acceptable and they are much sharper than predictions based on standard climate indices and baseline predictions that ignore climate information.

  10. Reconstruction of the solar coronal magnetic field, from active region to large scale

    NASA Astrophysics Data System (ADS)

    Amari, T.; Canou, A.; Delyon, F.; Aly, J. J.; Frey, P.; Alauzet, F.

    2011-12-01

    The low solar corona is dominated by the magnetic field which is created inside the sun by a dynamo process and then emerges into the atmosphere. This magnetic field plays an important role in most structures and phenomena observed at various wavelengths such as prominences, small and large scale eruptive events, and continuous heating of the plasma, and therefore it is important to understand its three-dimensional properties in order to elaborate efficient theoretical models. Unfortunately, the magnetic field is difficult to measure locally in the hot and tenuous corona. But this can be done at the level of the cooler and denser photosphere, and several instruments with high resolution vector magnetographs are currently available (THEMIS, Imaging Vector Magnetograph (IVM), the Advanced Stokes Polarimeter (ASP), SOLIS, HINODE, Solar Dynamics Observatory (SDO), or will be shortly available by future telescopes such as EST and solar missions as SOLAR-ORBITER. This has lead solar physicists to develop an approach which consists in " reconstructing" the coronal magnetic field from boundary data given on the photosphere. We will discuss some of the issues encountered in solving this problem as well our recent progress and results at the scale of active region scales or the larger one such as full sun scale.

  11. Improved confinement region without large magnetohydrodynamic activity in TPE-RX reversed-field pinch plasma

    SciTech Connect

    Yambe, Kiyoyuki; Hirano, Yoichi; Sakakita, Hajime; Koguchi, Haruhisa

    2014-11-15

    We found that spontaneous improved confinement was brought about depending on the operating region in the Toroidal Pinch Experiment-Reversed eXperiment (TPE-RX) reversed-field pinch plasma [Y. Yagi et al., Fusion Eng. Des. 45, 421 (1999)]. Gradual decay of the toroidal magnetic field at plasma surface B{sub tw} reversal makes it possible to realize a prolonged discharge, and the poloidal beta value and energy confinement time increase in the latter half of the discharge, where reversal and pinch parameters become shallow and low, respectively. In the latter half of the discharge, the plasma current and volume-averaged toroidal magnetic field 〈B{sub t}〉 increase again, the electron density slowly decays, the electron temperature and soft X-ray radiation intensity increase, and the magnetic fluctuations are markedly reduced. In this period of improved confinement, the value of (〈B{sub t}〉-B{sub tw})/B{sub pw}, where B{sub pw} is the poloidal magnetic field at the plasma surface, stays almost constant, which indicates that the dynamo action occurs without large magnetohydrodynamic activities.

  12. Photospheric Vector Magnetic Field Evolution of NOAA Active Region 11504 and the Ensuing CME

    NASA Astrophysics Data System (ADS)

    James, Alexander; Green, Lucie; Valori, Gherardo; van Driel-Gesztelyi, Lidia; Baker, Deborah; Brooks, David; Palmerio, Erika

    2016-05-01

    Coronal mass ejections (CMEs) are eruptions of billions of tonnes of plasma from the Sun that drive the most severe space weather effects we observe. In order to be able to produce forecasts of space weather with lead times of the order of days, accurate predictions of the occurrence of CMEs must be developed. The eruptive active-region studied in this work (NOAA 11504) is complex, featuring fragmentation of penumbral magnetic field in the days prior to eruption, as well as rotation of the leading sunspot. SDO/HMI vector photospheric magnetic field measurements are utilised alongside SDO/AIA multi-wavelength extreme ultra-violet (EUV) observations to study the dynamics of the photospheric and coronal structures, as well as Hinode/EIS spectroscopic measurements, including elemental composition data. The EUV data show flare ribbons as well as coronal dimmings, which are used to infer the orientation of the erupting flux rope. This flux rope orientation is then compared to in situ measurements of the flux rope. The vector magnetic field data is used to determine the possible contributions the field fragmentation and sunspot rotation may have made to the formation of the flux rope and the triggering of the CME.

  13. Improved confinement region without large magnetohydrodynamic activity in TPE-RX reversed-field pinch plasma

    NASA Astrophysics Data System (ADS)

    Yambe, Kiyoyuki; Hirano, Yoichi; Sakakita, Hajime; Koguchi, Haruhisa

    2014-11-01

    We found that spontaneous improved confinement was brought about depending on the operating region in the Toroidal Pinch Experiment-Reversed eXperiment (TPE-RX) reversed-field pinch plasma [Y. Yagi et al., Fusion Eng. Des. 45, 421 (1999)]. Gradual decay of the toroidal magnetic field at plasma surface Btw reversal makes it possible to realize a prolonged discharge, and the poloidal beta value and energy confinement time increase in the latter half of the discharge, where reversal and pinch parameters become shallow and low, respectively. In the latter half of the discharge, the plasma current and volume-averaged toroidal magnetic field increase again, the electron density slowly decays, the electron temperature and soft X-ray radiation intensity increase, and the magnetic fluctuations are markedly reduced. In this period of improved confinement, the value of (-Btw)/Bpw, where Bpw is the poloidal magnetic field at the plasma surface, stays almost constant, which indicates that the dynamo action occurs without large magnetohydrodynamic activities.

  14. The field and plasma configuration of a filament overlying a solar bipolar magnetic region

    NASA Technical Reports Server (NTRS)

    Low, B. C.

    1981-01-01

    This paper presents an analytic model for a finite-size straight filament suspended horizontally in a steady state over a bipolar magnetic region. The equations of magnetostatic equilibrium are integrated exactly. The solution obtained illustrates the roles played by the electric current, magnetic field, pressure, and plasma weight in the balance of force everywhere in space. A specific example of a filament of diameter 50,000 km, with a density two orders of magnitude over the corona and supported by a magnetic field of about 4 gauss is included. The filament temperature can take values ranging from a small fraction to a few times the coronal temperature, depending on the internal electric current of the filament. To produce a cool filament, such as the quiescent prominence, the solution is required to have an internal field with a strong component along the filament, giving rise to helical structures. A hot filament such as the X-ray coronal loop can be produced as a twisted magnetic flux tube embedded in a strong background field aligned parallel to the filament and having lower density and temperature. The basic steps of construction can be used to develop models more realistic than the ones presented for their analytic simplicity.

  15. Electric field control of E region coherent echoes: Evidence from radar observations at the South Pole

    NASA Astrophysics Data System (ADS)

    Makarevich, Roman A.; Forsythe, V. V.; Kellerman, A. C.

    2015-03-01

    Characteristics and formation mechanisms of E region plasma irregularities at high latitudes are investigated using observations with the newly deployed Super Dual Auroral Radar Network (SuperDARN) radar at the South Pole Antarctic station (SPS) near a magnetic latitude (MLAT) of 75°S. It is shown that E region echo occurrence at SPS exhibits a diurnal variation that is significantly different from those at auroral and polar cap latitudes. Moreover, analysis of major spectral populations also showed a distinct and previously unreported diurnal pattern. The plasma drift velocity estimates are derived at E region ranges of SPS, leveraging the SPS radar's position well within the MLAT region where SuperDARN convection estimates are well constrained by the data. It is shown that E region irregularity occurrence increases when the convection direction is within the SPS field of view and/or when the plasma drift component is comparable with the nominal ion-acoustic speed Cs of 350 m/s. This is the expected behavior for irregularities generated directly by the modified two-stream plasma instability (MTSI). On the other hand, irregularity velocity dependence on convection velocity showed an unexpected saturation at velocity values smaller than nominal Cs. It is demonstrated that the convection velocity at which irregularity velocity starts to differ from the convection component and to approach a maximum value is dependent on the magnetic aspect angle. Moreover, the maximum velocity value itself also depends on the aspect angle. The observed behavior is discussed in context of recent models that involve evolving aspect angles as a key characteristic of MTSI saturation.

  16. Field Studies of Broadband Aerosol Optical Extinction in the Ultraviolet Spectral Region

    NASA Astrophysics Data System (ADS)

    Washenfelder, R. A.; Attwood, A.; Brock, C. A.; Brown, S. S.

    2013-12-01

    Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross sections and complex refractive indices. In the case of brown carbon, its wavelength-dependent absorption in the ultraviolet spectral region has been suggested as an important component of aerosol radiative forcing. We describe a new field instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We deployed this instrument during the Fire Lab at Missoula Experiment during Fall 2012 to measure biomass burning aerosol, and again during the Southern Oxidant and Aerosol Study in summer 2013 to measure organic aerosol in the Southeastern U.S. In both field experiments, we determined aerosol optical extinction as a function of wavelength and can interpret this together with size distribution and composition measurements to characterize the aerosol optical properties and radiative forcing.

  17. Correlation of Coronal Plasma Properties and Solar Magnetic Field in a Decaying Active Region

    NASA Astrophysics Data System (ADS)

    Ko, Yuan-Kuen; Young, Peter R.; Muglach, Karin; Warren, Harry P.; Ugarte-Urra, Ignacio

    2016-08-01

    We present the analysis of a decaying active region observed by the EUV Imaging Spectrometer on Hinode during 2009 December 7–11. We investigated the temporal evolution of its structure exhibited by plasma at temperatures from 300,000 to 2.8 million degrees, and derived the electron density, differential emission measure, effective electron temperature, and elemental abundance ratios of Si/S and Fe/S (as a measure of the First Ionization Potential (FIP) Effect). We compared these coronal properties to the temporal evolution of the photospheric magnetic field strength obtained from the Solar and Heliospheric Observatory Michelson Doppler Imager magnetograms. We find that, while these coronal properties all decreased with time during this decay phase, the largest change was at plasma above 1.5 million degrees. The photospheric magnetic field strength also decreased with time but mainly for field strengths lower than about 70 Gauss. The effective electron temperature and the FIP bias seem to reach a “basal” state (at 1.5 × 106 K and 1.5, respectively) into the quiet Sun when the mean photospheric magnetic field (excluding all areas <10 G) weakened to below 35 G, while the electron density continued to decrease with the weakening field. These physical properties are all positively correlated with each other and the correlation is the strongest in the high-temperature plasma. Such correlation properties should be considered in the quest for our understanding of how the corona is heated. The variations in the elemental abundance should especially be considered together with the electron temperature and density.

  18. Threaded-Field-Line Model for the Transition Region and Solar Corona

    NASA Astrophysics Data System (ADS)

    Sokolov, I.; van der Holst, B.; Gombosi, T. I.

    2014-12-01

    In numerical simulations of the solar corona, both for the ambient state and especially for dynamical processes the most computational resources are spent for maintaining the numerical solution in the Low Solar Corona and in the transition region, where the temperature gradients are very sharp and the magnetic field has a complicated topology. The degraded computational efficiency is caused by the need in a highest resolution as well as the use of the fully three-dimensional implicit solver for electron heat conduction. On the other hand, the physical nature of the processes involved is rather simple (which still does not facilitate the numerical methods) as long as the heat fluxes as well as slow plasma motional velocities are aligned with the magnetic field. The Alfven wave turbulence, which is often believed to be the main driver of the solar wind and the main source of the coronal heating, is characterized by the Poynting flux of the waves, which is also aligned with the magnetic field. Therefore, the plasma state in any point of the three-dimensional grid in the Low Solar Corona can be found by solving a set of one-dimensional equations for the magnetic field line ("thread"), which passes through this point and connects it to the chromosphere and to the global Solar Corona. In the present paper we describe an innovative computational technology based upon the use of the magnetic-field-line-threads to forlmulate the boundary condition for the global solar corona model which traces the connection of each boundary point to the cromosphere along the threads.

  19. High-frequency expression for the field in the caustic region of a cylindrical reflector using Maslov's method

    NASA Astrophysics Data System (ADS)

    Hongo, Kohei; Ji, Yu

    1987-06-01

    High-frequency expressions in the caustic region are derived for the wave reflected by a circular and a parabolic cylindrical reflector using Maslov's method when a plane wave is incident obliquely. Maslov's method is a systematic procedure for predicting the field in the caustic region combining the simplicity of ray and generality of the transform method. Numerical computations are made for the field pattern around the caustic or cusp region and the variation of peak positions of the reflected field with respect to the incident angle.

  20. Nonlinear Force-Free and Potential-Field Models of Active-Region and Global Coronal Fields during the Whole Heliosphere Interval

    NASA Astrophysics Data System (ADS)

    Petrie, G. J. D.; Canou, A.; Amari, T.

    2011-12-01

    Between 24 March 2008 and 2 April 2008, the three active regions (ARs) NOAA 10987, 10988 and 10989 were observed daily by the Synoptic Optical Long-term Investigations of the Sun (SOLIS) Vector Spectro-Magnetograph (VSM) while they traversed the solar disk. We use these measurements and the nonlinear force-free magnetic field code XTRAPOL to reconstruct the coronal magnetic field for each active region and compare model field lines with images from the Solar Terrestrial RElations Observatory (STEREO) and Hinode X-ray Telescope (XRT) telescopes. Synoptic maps made from continuous, round-the-clock Global Oscillations Network Group (GONG) magnetograms provide information on the global photospheric field and potential-field source-surface models based on these maps describe the global coronal field during the Whole Heliosphere Interval (WHI) and its neighboring rotations. Features of the modeled global field, such as the coronal holes and streamer-belt locations, are discussed in comparison with extreme ultra-violet and coronagraph observations from STEREO. The global field is found to be far from a minimum, dipolar state. From the nonlinear models we compute physical quantities for the active regions such as the photospheric magnetic and electric current fluxes, the free magnetic energy and the relative helicity for each region each day where observations permit. The interconnectivity of the three regions is addressed in the context of the potential-field source-surface model. Using local and global quantities derived from the models, we briefly discuss the different observed activity levels of the regions.

  1. Wide Field CO Mapping in the Region of IRAS 19312+1950

    NASA Astrophysics Data System (ADS)

    Nakashima, Jun-ichi; Ladeyschikov, Dmitry A.; Sobolev, Andrej M.; Zhang, Yong; Hsia, Chih-Hao; Yung, Bosco H. K.

    2016-07-01

    We report the results of wide field CO mapping in the region of IRAS 19312+1950. This Infrared Astronomical Satellite (IRAS) object exhibits SiO/H2O/OH maser emission, and is embedded in a chemically rich molecular component, the origin of which is still unknown. In order to reveal the entire structure and gas mass of the surrounding molecular component for the first time, we have mapped a wide region around IRAS 19312+1950 in the 12CO J = 1–0, 13CO J = 1–0 and C18O J = 1–0 lines using the Nobeyama 45 m telescope. In conjunction with archival CO maps, we investigated a region up to 20‧ × 20‧ in size around this IRAS object. We calculated the CO gas mass assuming local thermal equilibrium, the stellar velocity through the interstellar medium assuming an analytic model of bow shock, and the absolute luminosity, using the latest archival data and trigonometric parallax distance. The derived gas mass (225 M ⊙–478 M ⊙) of the molecular component and the relatively large luminosity (2.63 × 104 L ⊙) suggest that the central SiO/H2O/OH maser source is a red supergiant rather than an asymptotic giant branch (AGB) star or post-AGB star.

  2. Cutoff frequencies and excitation threshold of artificial E region field aligned irregularities

    NASA Astrophysics Data System (ADS)

    Hysell, D. L.; Nossa, E.

    2009-12-01

    Artificial E region field aligned irregularities generated by HAARP have been observed using a coherent scatter radar imager in Homer, Alaska, in August of 2009. As in previous experiments, irregularities could be generated using O-mode pump frequencies both above and below the second electron gyroharmonic frequency, with no obvious differences in the irregularity properties in either case. However, echo suppression was observed when the pump frequency was swept across the second electron gyroharmonic frequency in small steps. This finding is consistent with the theory of thermal oscillating two-stream instability and the role of upper-hybrid waves, which are damped near gyroharmonic frequencies. The small frequency steps permit us to identify the width of the suppressed frequency band. Suppression was not complete, most likely because the double resonance matching condition cannot be met everywhere in the modified ionospheric volume. In separate experiments, the pump wave power was also varied in gradual, quadratic steps in order to identify the threshold in situ electric field amplitude for irregularity generation. The threshold field found this way, which was of the order of 100 mV/m, was smaller than previous experimental estimates and also approximately consistent with theory, although a great deal of uncertainty remains in both the contemporary theoretical formulation of the problem and the experimental conditions in the ionosphere.

  3. Explanation of the regional tectonic map of the southwestern coal field of Virginia

    SciTech Connect

    McLoughlin, T.F.

    1986-01-01

    The result of this study is a single tectonic map of the southwestern coal field of Virginia, which lies within the southern portion of the Cumberland Plateau. The tectonic map was produced by compiling previously identified and plotted major structural geologic features situated in southwestern Virginia and adjacent portions of Kentucky and West Virginia. Remote sensing imagery and published geologic reports were also utilized in the generation of this tectonic map. Except for the Cumberland overthrust block and its related thrust faults, the major faults within the southwestern Virginia coal field are high-angle normal and right-lateral strike-slip faults showing apparent displacements ranging from a few tens of feet (few tens of meters) to several miles (several kilometers). Folds within the coal field are broad, gentle flexures which include anticlines, synclines and a monocline with amplitudes measured in tens of feet to hundreds of feet (tens of meters to hundreds of meters). Brief descriptions of the general geometry and structural characteristics of the tectonic features are included for use with the regional map as an aid in conducting detailed geologic and environmental investigations. Evidence of structural faulting associated with the Gladeville anticline ( Indian Creek'' lineament) is also presented. 41 refs., 5 figs.

  4. Analysis and Prediction of the Critical Regions of Antimicrobial Peptides Based on Conditional Random Fields

    PubMed Central

    Chang, Kuan Y.; Lin, Tung-pei; Shih, Ling-Yi; Wang, Chien-Kuo

    2015-01-01

    Antimicrobial peptides (AMPs) are potent drug candidates against microbes such as bacteria, fungi, parasites, and viruses. The size of AMPs ranges from less than ten to hundreds of amino acids. Often only a few amino acids or the critical regions of antimicrobial proteins matter the functionality. Accurately predicting the AMP critical regions could benefit the experimental designs. However, no extensive analyses have been done specifically on the AMP critical regions and computational modeling on them is either non-existent or settled to other problems. With a focus on the AMP critical regions, we thus develop a computational model AMPcore by introducing a state-of-the-art machine learning method, conditional random fields. We generate a comprehensive dataset of 798 AMPs cores and a low similarity dataset of 510 representative AMP cores. AMPcore could reach a maximal accuracy of 90% and 0.79 Matthew’s correlation coefficient on the comprehensive dataset and a maximal accuracy of 83% and 0.66 MCC on the low similarity dataset. Our analyses of AMP cores follow what we know about AMPs: High in glycine and lysine, but low in aspartic acid, glutamic acid, and methionine; the abundance of α-helical structures; the dominance of positive net charges; the peculiarity of amphipathicity. Two amphipathic sequence motifs within the AMP cores, an amphipathic α-helix and an amphipathic π-helix, are revealed. In addition, a short sequence motif at the N-terminal boundary of AMP cores is reported for the first time: arginine at the P(-1) coupling with glycine at the P1 of AMP cores occurs the most, which might link to microbial cell adhesion. PMID:25803302

  5. Stress Field in Brazil with Focal Mechanism: Regional and Local Patterns

    NASA Astrophysics Data System (ADS)

    Dias, F.; Assumpcao, M.

    2013-05-01

    The knowledge of stress field is fundamental not only to understand driving forces and plate deformation but also in the study of intraplate seismicity. The stress field in Brazil has been determined mainly using focal mechanisms and a few breakout data and in-situ measurements. However the stress field still is poorly known in Brazil. The focal mechanisms of recent earthquakes (magnitude lower than 5 mb) were studied using waveform modeling. We stacked the record of several teleseismic stations ( delta > 30°) stacked groups of stations separated according to distance and azimuth. Every record was visually inspected and those with a good signal/noise ratio (SNR) were grouped in windows of ten degrees distance and stacked. The teleseismic P-wave of the stacked signals was modeled using the hudson96 program of Herrmann seismology package (Herrmann, 2002) and the consistency of focal mechanism with the first-motion was checked. Some events in central Brazil were recorded by closer stations (~ 1000 km) and the moment tensor was determined with the ISOLA code (Sokos & Zahradnik, 2008). With the focal mechanisms available in literature and those obtained in this work, we were able to identify some patterns: the central region shows a purely compressional pattern (E-W SHmax), which is predicted by regional theoretical models (Richardson & Coblentz, 1996 and the TD0 model of Lithgow & Bertelloni, 2004). Meanwhile in the Amazon we find an indication of SHmax oriented in the SE-NW direction, probably caused by the Caribbean plate interaction (Meijer, 1995). In northern coastal region, the compression rotates following the coastline, which indicates an important local component related to spreading effects at the continental/oceanic transition (Assumpção, 1998) and flexural stresses caused by sedimentary load in Amazon Fan. We determine the focal mechanism of several events in Brazil using different techniques according to the available data. The major difficulty is to

  6. Resolving the coronal line region of NGC 1068 with near-infrared integral field spectroscopy

    NASA Astrophysics Data System (ADS)

    Mazzalay, X.; Rodríguez-Ardila, A.; Komossa, S.; McGregor, Peter J.

    2013-04-01

    We present adaptive optics-assisted J- and K-band integral field spectroscopy of the inner 300 × 300 pc of the Seyfert 2 galaxy NGC 1068. The data were obtained with the Gemini Near-infrared Integral-Field Spectrograph integral field unit spectrometer, which provided us with high-spatial and high-spectral resolution sampling. The wavelength range covered by the observations allowed us to study the [Ca VIII], [Si VI], [Si VII], [Al IX] and [S IX] coronal line (CL) emission, covering ionization potentials up to 328 eV. The observations reveal very rich and complex structures, both in terms of velocity fields and emission-line ratios. The CL emission is elongated along the NE-SW direction, with the stronger emission preferentially localized to the NE of the nucleus. CLs are emitted by gas covering a wide range of velocities, with maximum blueshifts/redshifts of ˜ -1600/1000 km s-1. There is a trend for the gas located on the NE side of the nucleus to be blueshifted while the gas located towards the SW is redshifted. The morphology and the kinematics of the near-infrared CLs are in very good agreement with the ones displayed by low-ionization lines and optical CLs, suggesting a common origin. The line flux distributions, velocity maps, ionization structure (traced by the [Si VII]/[Si VI] emission-line ratio) and low-ionization emission-line ratios (i.e. [Fe II]/Paβ and [Fe II]/[P II]) suggest that the radio jet plays an important role in the structure of the CL region of this object, and possibly in its kinematics.

  7. Paleosecular Variation and Time-Averaged Field Behavior: Global and Regional Signatures

    NASA Astrophysics Data System (ADS)

    Johnson, C. L.; Cromwell, G.; Tauxe, L.; Constable, C.

    2012-12-01

    We use an updated global dataset of directional and intensity data from lava flows to investigate time-averaged field (TAF) and paleosecular variation (PSV) signatures regionally and globally. The data set includes observations from the past 10 Ma, but we focus our investigations on the field structure over past 5 Ma, in particular during the Brunhes and Matuyama. We restrict our analyses to sites with at least 5 samples (all of which have been stepwise demagnetized), and for which the estimate of the Fisher precision parameter, k, is at least 50. The data set comprises 1572 sites from the past 5 Ma that span latitudes 78oS to 71oN; of these ˜40% are from the Brunhes chron and ˜20% are from the Matuyama chron. Age control at the site level is variable because radiometric dates are available for only about one third of our sites. New TAF models for the Brunhes show longitudinal structure. In particular, high latitude flux lobes are observed, constrained by improved data sets from N. and S. America, Japan, and New Zealand. We use resampling techniques to examine possible biases in the TAF and PSV incurred by uneven temporal sampling, and the limited age information available for many sites. Results from Hawaii indicate that resampling of the paleodirectional data onto a uniform temporal distribution, incorporating site ages and age errors leads to a TAF estimate for the Brunhes that is close to that reported for the actual data set, but a PSV estimate (virtual geomagnetic pole dispersion) that is increased relative to that obtained from the unevenly sampled data. The global distribution of sites in our dataset allows us to investigate possible hemispheric asymmetries in field structure, in particular differences between north and south high latitude field behavior and low latitude differences between the Pacific and Atlantic hemispheres.

  8. MAGNETIC FIELDS IN LARGE-DIAMETER H II REGIONS REVEALED BY THE FARADAY ROTATION OF COMPACT EXTRAGALACTIC RADIO SOURCES

    SciTech Connect

    Harvey-Smith, L.; Madsen, G. J.; Gaensler, B. M.

    2011-08-01

    We present a study of the line-of-sight magnetic fields in five large-diameter Galactic H II regions. Using the Faraday rotation of background polarized radio sources, as well as dust-corrected H{alpha} surface brightness as a probe of electron density, we estimated the strength and orientation of the magnetic field along 93 individual sight lines through the H II regions. Each of the H II regions displayed a coherent magnetic field. The magnetic field strength (line-of-sight component) in the regions ranges from 2 to 6 {mu}G, which is similar to the typical magnetic field strength in the diffuse interstellar medium. We investigated the relationship between magnetic field strength and electron density in the five H II regions. The slope of magnetic field versus density in the low-density regime (0.8 cm{sup -3} < n{sub e} <30 cm{sup -3}) is very slightly above zero. We also calculated the ratio of thermal to magnetic pressure, {beta}{sub th}, for each data point, which fell in the range 1.01 < {beta}{sub th} < 25. Finally, we studied the orientation of the magnetic field in the solar neighborhood (d < 1.1 kpc) using our data from five H II regions along with existing measurements of the line-of-sight magnetic field strength from polarized pulsars whose distances have been determined from their annual parallax. We identify a net direction for the magnetic field in the solar neighborhood, but find no evidence for a preferred vertical direction of the magnetic field above or below the Galactic plane.

  9. On the High- and Low- Altitude Limits of the Auroral Electric Field Region

    NASA Technical Reports Server (NTRS)

    Reiff, P. H.; Lu, G.; Burch, J. L.; Winningham, J. D.; Frank, L. A.; Craven, J. D.; Peterson, W. K.; Heelis, R. A.

    1993-01-01

    Using measurements from the High Altitude Plasma Instrument (HAPI) on the Dynamics-Explorer 1 (DE-1) spacecraft and the Low Altitude Plasma Instrument (LAPI) on Dynamics Explorer 2 (DE 2), we investigate both die high altitude and low altitude extents of the auroral acceleration region. To infer the high altitude limit, we searched the HAPI data base for evidence of upward-directed auroral electric fields located above the spacecraft when the HAPI spacecraft is above 9000 km altitude. We find that such acceleration is common when DE-1 flies through die auroral oval at an altitude of 9,000-11,000 km. At altitudes above 11,000 km, the fraction of the orbits with evidence of at least a 1000 V potential drop above the spacecraft falls, becoming essentially zero above an altitude of 15,000 km. Above that altitude, small (100 V) potential drops are frequently observed, but only rarely are approx. 1 kV potentials observed, typically associated with polar cap or 'theta' arcs or westward traveling surges. To investigate the low-altitude limit of the auroral acceleration region, we use conjunctions of DE 1 and DE 2 along auroral field lines and match the upgoing fluxes of ionospheric ions observed by DE 2 with the flux of accelerated upgoing ions observed at DE 1. Calculating the ionospheric scale height from the ion and electron temperatures and assuming that the parallel flow velocity is independent of height above 800 km, we calculate the altitude at which the upwelling ionospheric ions are effectively completely lost to upward acceleration. The initial lowest-altitude acceleration process could be either a perpendicular acceleration or a parallel electric field, but it must be sufficient to give the entire distribution escape energy. We find that in the two cases studied, near the region of peak auroral potential drop the altitude of this acceleration was around 1700 km (near the O/H neutral crossover altitude), but was significantly higher (approx. 2000 km) near the

  10. Nonlinear effects of locally heterogeneous hydraulic conductivity fields on regional stream-aquifer exchanges

    NASA Astrophysics Data System (ADS)

    Zhu, J.; Winter, C. L.; Wang, Z.

    2015-11-01

    Computational experiments are performed to evaluate the effects of locally heterogeneous conductivity fields on regional exchanges of water between stream and aquifer systems in the Middle Heihe River basin (MHRB) of northwestern China. The effects are found to be nonlinear in the sense that simulated discharges from aquifers to streams are systematically lower than discharges produced by a base model parameterized with relatively coarse effective conductivity. A similar, but weaker, effect is observed for stream leakage. The study is organized around three hypotheses: (H1) small-scale spatial variations of conductivity significantly affect regional exchanges of water between streams and aquifers in river basins, (H2) aggregating small-scale heterogeneities into regional effective parameters systematically biases estimates of stream-aquifer exchanges, and (H3) the biases result from slow paths in groundwater flow that emerge due to small-scale heterogeneities. The hypotheses are evaluated by comparing stream-aquifer fluxes produced by the base model to fluxes simulated using realizations of the MHRB characterized by local (grid-scale) heterogeneity. Levels of local heterogeneity are manipulated as control variables by adjusting coefficients of variation. All models are implemented using the MODFLOW (Modular Three-dimensional Finite-difference Groundwater Flow Model) simulation environment, and the PEST (parameter estimation) tool is used to calibrate effective conductivities defined over 16 zones within the MHRB. The effective parameters are also used as expected values to develop lognormally distributed conductivity (K) fields on local grid scales. Stream-aquifer exchanges are simulated with K fields at both scales and then compared. Results show that the effects of small-scale heterogeneities significantly influence exchanges with simulations based on local-scale heterogeneities always producing discharges that are less than those produced by the base model

  11. Nonlinear effects of locally heterogeneous hydraulic conductivity fields on regional stream-aquifer exchanges

    NASA Astrophysics Data System (ADS)

    Zhu, J.; Winter, C. L.; Wang, Z.

    2015-08-01

    Computational experiments are performed to evaluate the effects of locally heterogeneous conductivity fields on regional exchanges of water between stream and aquifer systems in the Middle Heihe River Basin (MHRB) of northwestern China. The effects are found to be nonlinear in the sense that simulated discharges from aquifers to streams are systematically lower than discharges produced by a base model parameterized with relatively coarse effective conductivity. A similar, but weaker, effect is observed for stream leakage. The study is organized around three hypotheses: (H1) small-scale spatial variations of conductivity significantly affect regional exchanges of water between streams and aquifers in river basins, (H2) aggregating small-scale heterogeneities into regional effective parameters systematically biases estimates of stream-aquifer exchanges, and (H3) the biases result from slow-paths in groundwater flow that emerge due to small-scale heterogeneities. The hypotheses are evaluated by comparing stream-aquifer fluxes produced by the base model to fluxes simulated using realizations of the MHRB characterized by local (grid-scale) heterogeneity. Levels of local heterogeneity are manipulated as control variables by adjusting coefficients of variation. All models are implemented using the MODFLOW simulation environment, and the PEST tool is used to calibrate effective conductivities defined over 16 zones within the MHRB. The effective parameters are also used as expected values to develop log-normally distributed conductivity (K) fields on local grid scales. Stream-aquifer exchanges are simulated with K fields at both scales and then compared. Results show that the effects of small-scale heterogeneities significantly influence exchanges with simulations based on local-scale heterogeneities always producing discharges that are less than those produced by the base model. Although aquifer heterogeneities are uncorrelated at local scales, they appear to induce

  12. Reconnaissance of ground-water resources in the Eastern Coal Field Region, Kentucky

    USGS Publications Warehouse

    Price, William E.; Mull, D.S.; Kilburn, Chabot

    1962-01-01

    In the Eastern Coal Field region of Kentucky, water is obtained from consolidated sedimentary rocks ranging in age from Devonian to Pennsylvanian and from unconsolidated sediments of Quaternary age. About 95 percent of the area is underlain by shale, sandstone, and coal of Pennsylvanian age. Principal factors governing the availability of water in the region are depth, topographic location, and the lithology of the aquifer penetrated. In general, the yield of the well increases as the depth increases. Wells drilled in topographic lows, such as valleys, are likely to yield more water than wells drilled on topographic highs, such as hills. Sand and gravel, present in thick beds in the alluvium along the Ohio River, form the most productive aquifer in the Eastern Coal Field. Of the consolidated rocks in the region sandstone strata are the best aquifers chiefly because joints, openings along bedding planes, and intergranular pore spaces are best developed in them. Shale also supplies water to many wells in the region, chiefly from joints and openings along bedding planes. Coal constitutes a very small part of the sedimentary section, but it yields water from fractures to many wells. Limestone yields water readily from solution cavities developed along joint and bedding-plane openings. The availability of water in different parts of the region was determined chiefly by analyzing well data collected during the reconnaissance. The resulting water-availability maps, published as hydrologic investigations atlases (Price and others, 1961 a, b; Kilburn and others, 1961) were designed to be used in conjunction with this report. The maps were constructed by dividing the region into 5 physiographic areas, into 10 subareas based chiefly on lithologic facies, and, in the case of the Kanawha section, into 2 quality-of-water areas. The 5 physiographic areas are the Knobs, Mississippian Plateau, Cumberland Plateau section, Kanawha section, and Cumberland Mountain section. The 10

  13. Sediment and phosphorus fluxes - monitoring and modelling from field to regional scale - connectivity implications

    NASA Astrophysics Data System (ADS)

    Bauer, Miroslav; Zumr, David; Krása, Josef; Dostál, Tomáš; Jáchymová, Barbora; Rosendorf, Pavel

    2015-04-01

    Sediment and phosphorus fluxes - monitoring and modelling from field to regional scale - connectivity implications Miroslav Bauer1), David Zumr1), Josef Krása1), Tomáš Dostal1), Barbora Jáchymová1), Pavel Rosendorf2) Czech Technical University in Prague1, Water Research Institute of T.G.M. 2, Agricultural landscape management has a strong influences on sediment and nutrients flow paths from field to streams and reservoirs. According to many studies water erosion driven phosphorus can play important role in total phosphorous budgets in catchments and accelerate eutrophication process in vulnerable reservoirs. Research team of CTU Prague focuses on research of sediment transport processes from a small plot scale to regional scale. Using field rainfall simulator the data are collected to assess the fluxes in the scale from one to several square meters and to analyze the plot size effect on the runoff, solid particles and phosphorous transport processes (see corresponding posters of Jachymova et al., Kavka et al., Laburda et al., Zumr et al.). Running fully agricultural experimental catchment of 49 ha (Nucice, Czech Republic) and experimental soil erosion plots (Bykovice, Czech Republic) we analyze runoff and soil erosion with the aim to upscale the results from single plot studies to the catchment scale. Soil erosion is also monitored by means of spatially distributed soil sampling and photogrammetry analyses. The water flow pathways via subsurface and surface runoff and the temporary variable catchment connectivity are studied here. Finally the research team produced unique large extent study, performed by WATEM/SEDEM model adopted for erosion driven phosphorus fluxes modelling, for the area of 1/3 of the Czech Republic (ca 31500 km2) in the resolution (pixel size) of 10 by 10 meters, with estimated connectivity from single field to outlet reservoirs of large catchments, including stream topology, sediment trapping efficiencies of all ponds and reservoirs within

  14. Field-aligned current signatures in the near-tail region. I - ISEE observations in the plasma sheet boundary layer

    NASA Technical Reports Server (NTRS)

    Ohtani, S.; Kokubun, S.; Elphic, R. C.; Russell, C. T.

    1988-01-01

    Field-aligned currents in the near-tail region are examined using ISEE magnetometer data. Two substorms (the 1054 UT and the 1436 UT substorms on March 22, 1979) were examined, demonstrating the consistency of the current polarity and intensity with observations at lower altitudes, which suggests that field-aligned currents in the plasma sheet boundary layer are parts of the large-scale current system, the region-1 system. An examination of the steplike changes of the magnetic field direction, which correspond to the spacecraft crossing of a net field-aligned current, showed that the field-aligned currents in the plasma sheet boundary layer have the same polarity as the region-1 system.

  15. Information Services; A Survey of the History and Present Status of the Field. MOREL Regional Information System for Educators.

    ERIC Educational Resources Information Center

    Grimes, George

    This document is one of a series describing the background, functions, and utilization of the Regional Information System (RIS) developed by the Michigan-Ohio Regional Educational Laboratory (MOREL). The continuing history of the field of librarianship and information services is reviewed in this report. The first part covers ancient times to the…

  16. Transforming Your Regional Economy through Uncertainty and Surprise: Learning from Complexity Science, Network Theory and the Field

    NASA Astrophysics Data System (ADS)

    Holley, June

    The field of regional development blossomed in the last decade, as researchers and practitioners increasingly asserted that the region was the most effective geographic unit for supporting the excellence and innovation of entrepreneurs. See, for example, the many studies by the European Union and the work by Michael Porter.

  17. The Southern African Regional Science Initiative (SAFARI 2000): Overview of the Dry Season Field Campaign

    NASA Technical Reports Server (NTRS)

    Swap, R. J.; Annegarn, H. J.; Suttles, J. T.; Haywood, J.; Helmlinger, M. C.; Hely, C.; Hobbs, P. V.; Holben, B. N.; Ji, J.; King, M. D.

    2002-01-01

    The Southern African Regional Science Initiative (SAFARI 2000) is an international project investigating the earth atmosphere -human system in southern Africa. The programme was conducted over a two year period from March 1999 to March 2001. The dry season field campaign (August-September 2000) was the most intensive activity involved over 200 scientist from eighteen countries. The main objectives were to characterize and quantify biogenic, pyrogenic and anthropogenic aerosol and trace gas emissions and their transport and transformations in the atmosphere and to validate NASA's Earth Observing System's Satellite Terra within a scientific context. Five aircraft-- two South African Weather Service Aeorcommanders, the University of Washington's CV-880, the U.K. Meteorological Office's C-130, and NASA's ER-2 --with different altitude capabilities, participated in the campaign. Additional airborne sampling of southern African air masses, that had moved downwind of the subcontinent, was conducted by the CSIRO over Australia. Multiple Observations were made in various geographical sections under different synoptic conditions. Airborne missions were designed to optimize the value of synchronous over-flights of the Terra Satellite platform, above regional ground validation and science targets. Numerous smaller scale ground validation activities took place throughout the subcontinent during the campaign period.

  18. Influence of interplanetary magnetic field and solar wind on auroral brightness in different regions

    NASA Astrophysics Data System (ADS)

    Yang, Y. F.; Lu, J. Y.; Wang, J.-S.; Peng, Z.; Zhou, L.

    2013-01-01

    Abstract<p label="1">By integrating and averaging the auroral brightness from Polar Ultraviolet Imager auroral images, which have the whole auroral ovals, and combining the observation data of interplanetary magnetic <span class="hlt">field</span> (IMF) and solar wind from NASA Operating Missions as a Node on the Internet (OMNI), we investigate the influence of IMF and solar wind on auroral activities, and analyze the separate roles of the solar wind dynamic pressure, density, and velocity on aurora, respectively. We statistically analyze the relations between the interplanetary conditions and the auroral brightness in dawnside, dayside, duskside, and nightside. It is found that the three components of the IMF have different effects on the auroral brightness in the different <span class="hlt">regions</span>. Different from the nightside auroral brightness, the dawnside, dayside, and duskside auroral brightness are affected by the IMF Bx, and By components more significantly. The IMF Bx and By components have different effects on these three <span class="hlt">regional</span> auroral brightness under the opposite polarities of the IMF Bz. As expected, the nightside aurora is mainly affected by the IMF Bz, and under southward IMF, the larger the |Bz|, the brighter the nightside aurora. The IMF Bx and By components have no visible effects. On the other hand, it is also found that the aurora is not intensified singly with the increase of the solar wind dynamic pressure: when only the dynamic pressure is high, but the solar wind velocity is not very fast, the aurora will not necessarily be intensified significantly. These results can be used to qualitatively predict the auroral activities in different <span class="hlt">regions</span> for various interplanetary conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26994789','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26994789"><span id="translatedtitle">High <span class="hlt">field</span> FT-ICR mass spectrometry for molecular characterization of snow board from Moscow <span class="hlt">regions</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mazur, Dmitry M; Harir, Mourad; Schmitt-Kopplin, Philippe; Polyakova, Olga V; Lebedev, Albert T</p> <p>2016-07-01</p> <p>High <span class="hlt">field</span> Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry analysis of eight snow samples from Moscow city allowed us to identify more than 2000 various elemental compositions corresponding to <span class="hlt">regional</span> air pollutants. The hierarchical cluster analysis (HCA) of the data showed good concordance of three main groups of samples with the main wind directions. The North-West group (A1) is represented by several homologous CHOS series of aliphatic organic aerosols. They may form as a result of enhanced photochemical reactions including oxidation of hydrocarbons with sulfonations due to higher amount of SO2 emissions in the atmosphere in this <span class="hlt">region</span>. Group A2, corresponding to the South-East part of Moscow, contains large amount of oxidized hydrocarbons of different sources that may form during oxidation in atmosphere. These hydrocarbons appear correlated to emissions from traffic, neighboring oil refinery, and power plants. Another family of compounds specific for this <span class="hlt">region</span> involves CHNO substances formed during oxidation processes including NOx and NO3 radical since emissions of NOx are higher in this part of the city. Group A3 is rich in CHO type of compounds with high H/C and low O/C ratios, which is characteristic of oxidized hydrocarbon-like organic aerosol. CHNO types of compounds in A3 group are probably nitro derivatives of condensed hydrocarbons such as PAH. This non-targeted profiling revealed site specific distribution of pollutants and gives a chance to develop new strategies in air quality control and further studies of Moscow environment. PMID:26994789</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.H31D1138S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H31D1138S"><span id="translatedtitle">Monitoring and Modeling Water and Energy Fluxes in North China Plain: From <span class="hlt">Field</span> to <span class="hlt">Regional</span> Scales</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, Y.</p> <p>2012-12-01</p> <p>North China Plain is one of the mostly water deficit <span class="hlt">region</span> in the world. Even though the total water withdrawal from surface and groundwater exceeded its renewable ability for long years, due to its importance to balance the food budget in China, large amount of groundwater is still extracted every year for intensive irrigation. With winter wheat and summer maize double-cropping system, the grain yield of NCP can reach a very high level of around 15 t/ha annually, which is largely depended on timely irrigation. As a result, the ceaseless over exploitation of groundwater caused serious environmental and ecological problems, e.g. nearly all the rivers run drying-up at plain areas, groundwater declined, land subsidence, and wetland shrank. The decrease in precipitation over past half century reinforced the water shortage in NCP. The sustainability of both the water resources and agriculture became the most important issue in this <span class="hlt">region</span>. A key issue to the sustainable use of water resources is to improve the water use efficiency and reduce agricultural water consumptions. This study will introduce the efforts we put to clarify the water and heat balances in irrigated agricultural lands and its implications to crop yield, hydrology, and water resources evolution in NCP. We established a multi-scale observation system in NCP to study the surface water and heat processes and agricultural aspect of hydrological cycle in past years. Multi-disciplinary methods are adopted into this research such as micro-meteorologic, isotopic, soil hydrologic methods at the <span class="hlt">field</span> scale, and remote sensing and modeling for study the water fluxes over <span class="hlt">regional</span> scale. Detailed research activities and interesting as well as some initial results will be introduced at the workshop.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930044662&hterms=BIPOLAR&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DBIPOLAR','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930044662&hterms=BIPOLAR&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DBIPOLAR"><span id="translatedtitle">The origin of morphological asymmetries in bipolar active <span class="hlt">regions</span>. [magnetic <span class="hlt">field</span> in solar convective envelope</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fan, Y.; Fisher, G. H.; Deluca, E. E.</p> <p>1993-01-01</p> <p>A series of 3D numerical simulations was carried out to examine the dynamical evolution of emerging flux loops in the solar convective envelope. The innermost portions of the loops are anchored beneath the base of the convective zone by the subadiabatic temperature gradient of the underlying overshoot <span class="hlt">region</span>. It is found that, as the emerging loops approach the photosphere, the magnetic <span class="hlt">field</span> strength of the leading side of each rising loop is about twice as large as that of the following side at the same depth. The evacuation of plasma out of the leading side of the rising loop results in an enhanced magnetic <span class="hlt">field</span> strength there compared with the following side. It is argued that this result provides a natural explanation for the fact that the preceding (leading) polarity tends to have a less organized and more fragmented appearance, and that the preceding spots tend to be larger in area and fewer in number, and have a longer lifetime than the following spots.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5491528','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5491528"><span id="translatedtitle">Thermodynamic coupling of heat and matter flows in near-<span class="hlt">field</span> <span class="hlt">regions</span> of nuclear waste repositories</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Carnahan, C.L.</p> <p>1983-11-01</p> <p>In near-<span class="hlt">field</span> <span class="hlt">regions</span> of nuclear waste repositories, thermodynamically coupled flows of heat and matter can occur in addition to the independent flows in the presence of gradients of temperature, hydraulic potential, and composition. The following coupled effects can occur: thermal osmosis, thermal diffusion, chemical osmosis, thermal filtration, diffusion thermal effect, ultrafiltration, and coupled diffusion. Flows of heat and matter associated with these effects can modify the flows predictable from the direct effects, which are expressed by Fourier's law, Darcy's law, and Fick's law. The coupled effects can be treated quantitatively together with the direct effects by the methods of the thermodynamics of irreversible processes. The extent of departure of fully coupled flows from predictions based only on consideration of direct effects depends on the strengths of the gradients driving flows, and may be significant at early times in backfills and in near-<span class="hlt">field</span> geologic environments of repositories. Approximate calculations using data from the literature and reasonable assumptions of repository conditions indicate that thermal-osmotic and chemical-osmotic flows of water in semipermeable backfills may exceed Darcian flows by two to three orders of magnitude, while flows of solutes may be reduced greatly by ultrafiltration and chemical osmosis, relative to the flows predicted by advection and diffusion alone. In permeable materials, thermal diffusion may contribute to solute flows to a smaller, but still significant, extent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016cosp...41E1399N&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016cosp...41E1399N&link_type=ABSTRACT"><span id="translatedtitle">PCA Analysis of the Geomagnetic <span class="hlt">Field</span> at Mid-Latitude <span class="hlt">Regions</span> during High Solar Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Natali, Maria Paula; Meza, Amalia Margarita</p> <p>2016-07-01</p> <p>Our study is focused on the analysis of the geomagnetic variability of the H, D and Z components in the Northern hemisphere at mid-latitudes. We analyze two different local times, noon and night, recorded by 22 permanent observatories distributed over Europe and North America during a period of four years of high solar activity comprising 2000-2003. We used Principal Component Analysis (PCA) in order to identify the spatial and temporal variations of the geomagnetic <span class="hlt">field</span> components. This technique produces a quite compact representation of the data by defining an orthonormal base derived from correlation within the data set. This helps us to identify possible causes of seasonal variations and anomalies, linking them with already observed currents. In fact, the analysis of PCA amplitudes and modes support our interpretation of the spectral and statistical features of the geomagnetic <span class="hlt">field</span>. Using the first two modes we reconstruct more than 90% of the original signal for the European and North American <span class="hlt">region</span>. The obtained results reconfirm the existence of a latitudinal dependence in the geomagnetic components during nighttime hours, associated with the ring current. During noon, the first mode represent the dominant component of the current originated by the ionosphere, while the second mode show the presence of a longitudinal variation at both sides of the longitudes with zero declination for Europe and North America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5049141','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5049141"><span id="translatedtitle">Signatures of the high-altitude polar cusp and dayside auroral <span class="hlt">regions</span> as seen by the Viking electric <span class="hlt">field</span> experiment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Marklund, G.T.; Blomberg, L.G.; Faelthammar, C.G. ); Erlandson, R.E.; Potemra, T.A. )</p> <p>1990-05-01</p> <p>Electric <span class="hlt">field</span> and satellite potential observations along 42 Viking orbits in the high-altitude (2R{sub E}) polar cusp and dayside auroral <span class="hlt">region</span> have been examined. Within the cusp the plasma density usually reaches a maximum, and it is typically very homogeneous, in contrast to the irregular and lower density in the cleft and dayside auroral <span class="hlt">regions</span>. The maxima in the plasma density are sometimes anticorrelated with the magnetic <span class="hlt">field</span> strength, indicating a diamagnetic effect. The entire cusp and dayside auroral <span class="hlt">regions</span> are characterized by irregular and burstlike electric <span class="hlt">fields</span>, comprising <span class="hlt">field</span> reversals on various scales (up to 3 min or 500 km), the larger scales, however, being rare in the cusp. Another common feature in these <span class="hlt">regions</span> is the high correlation between mutually orthogonal components of the electric and magnetic <span class="hlt">fields</span>, both for large-scale variations across spatial structures and for wave and pulsations in the ULF frequency range. The electric <span class="hlt">field</span> signatures in the cusp (in the 1100-1300 MLT sector) are, however, characteristically different from the cleft and oval <span class="hlt">field</span> signatures in that the electric <span class="hlt">field</span> is usually less intense and less structured and not correlated with the substorm activity level.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.1404D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.1404D"><span id="translatedtitle">Effects of tropical cyclone characteristics on the surface wave <span class="hlt">fields</span> in the Australian North West <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Drost, Edwin; Lowe, Ryan; Péquignet, Christine; Ivey, Greg; Jones, Nicole</p> <p>2015-04-01</p> <p>The northwestern Australian coastline is subject to frequent extreme wave forcing resulting from tropical cyclones (TCs) during the summer months on Australia's North West Shelf (NWS). Compared to the northern hemisphere, knowledge about the wave climate, and TC generated waves in particular on the NWS is limited. TCs on the NWS show considerable variability in paths: some move predominantly parallel to the coastline, while others propagate in a coast-normal direction. It has been suggested that surface wave <span class="hlt">fields</span> generated by coast-parallel moving TCs are different compared to TCs moving in a coast-normal direction across the shelf. In particular, wave heights generated by coast-parallel storms may be limited in size due to both refraction and bottom friction effects. First, this study evaluates the performance of a numerical wave model (SWAN) to hindcast the surface wave <span class="hlt">fields</span> under different TC conditions forced by a parametric TC wind model of the <span class="hlt">region</span>. Hindcast simulations were run for 4 case studies: the coast-parallel TCs Nicholas (2008) and Bianca (2011), and the coast-normal TCs Lua (2012) and Christine (2013). Model output was compared both temporally and spatially by in situ wave buoy data and satellite altimeter data and generally showed a good agreement for throughout the history of these TCs. However, for the more intense and larger system TC Lua, the model was found to overestimate the significant wave heights, especially in the left front quadrant of the storm. A modified SWAN model using adjusted wave energy dissipation terms was found to improve model output under these conditions. Second, output from the numerical simulations is used to analyse the mechanisms behind the generation and dissipation of the wave <span class="hlt">field</span> and to relate them to tropical cyclone characteristics including the radius of maximum winds and the storm translation speed and direction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15940495','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15940495"><span id="translatedtitle">Cortical afferents to the smooth-pursuit <span class="hlt">region</span> of the macaque monkey's frontal eye <span class="hlt">field</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stanton, Gregory B; Friedman, Harriet R; Dias, Elisa C; Bruce, Charles J</p> <p>2005-08-01</p> <p>In primates, the frontal eye <span class="hlt">field</span> (FEF) contains separate representations of saccadic and smooth-pursuit eye movements. The smooth-pursuit <span class="hlt">region</span> (FEFsem) in macaque monkeys lies principally in the fundus and deep posterior wall of the arcuate sulcus, between the FEF saccade <span class="hlt">region</span> (FEFsac) in the anterior wall and somatomotor areas on the posterior wall and convexity. In this study, cortical afferents to FEFsem were mapped by injecting retrograde tracers (WGA-HRP and fast blue) into electrophysiologically identified FEFsem sites in two monkeys. In the frontal lobe, labeled neurons were found mostly on the ipsilateral side in the (1) supplementary eye <span class="hlt">field</span> <span class="hlt">region</span> and lateral area F7; (2) area F2 along the superior limb of the arcuate sulcus; and (3) in the buried cortex of the arcuate sulcus extending along the superior and inferior limbs and including FEFsac and adjacent areas 8, 45, and PMv. Labeled cells were also found in the caudal periprincipal cortex (area 46) in one monkey. Labeled cells were found bilaterally in the frontal lobe in the deep posterior walls of the arcuate sulcus and postarcuate spurs and in cingulate motor areas 24 and 24c. In postcentral cortical areas all labeling was ipsilateral and there were two major foci of labeled cells: (1) the depths of the intraparietal sulcus including areas VIP, LIP, and PEa, and (2) the anterior wall and fundus of the superior temporal sulcus including areas PP and MST. Smaller numbers of labeled cells were found in superior temporal sulcal areas FST, MT, and STP, posterior cingulate area 23b, area 3a within the central sulcus, areas SII, RI, Tpt in the lateral sulcus, and parietal areas 7a, 7b, PEc, MIP, DP, and V3A. Many of these posterior afferent cortical areas code visual-motion (MT, MST, and FST) or visual-motion and vestibular (PP, VIP) signals, consistent with the responses of neurons in FEFsem and with the overall physiology and anatomy of the smooth-pursuit eye movement system. PMID:15940495</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......116M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......116M"><span id="translatedtitle">Experimental studies on remanence acquisition processes and <span class="hlt">regional</span> geomagnetic <span class="hlt">field</span> variability from archeointensity studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mitra, Ritayan</p> <p></p> <p>The dissertation comprises two separate topics. Chapters 2 and 3 are experimental studies on remanence acquisition processes. Chapters 4 and 5 investigate the geomagnetic <span class="hlt">field</span> variability in Africa and India between 1000 BCE and 1000 CE. Chapter 2 is a study in which the role of flocculation in sedimentary magnetization is analyzed with the help of laboratory redeposition experiments and a simple numerical model. At small floc sizes DRM acquisition is likely to be non-linear but it may record the directions with higher fidelity. In environments having bigger flocs the sediments are likely to record either intensities or directions with high fidelity, but not both. Also flocculation may inhibit a large fraction of magnetic grains from contributing to the net remanence and this might have consequences for intensity normalization in sediments. Chapter 3 presents a fresh perspective on the long standing debate of the nature of magnetocrystalline anisotropy in Mid-Ocean Ridge Basalts (MORBs). A new parameter, IRAT, defined as the ratio of the isothermal remanences in antiparallel directions is used to differentiate between uniaxial single domain grains (IRAT ˜1) and multiaxial single domain grains (IRAT<1). The theoretical predictions were first validated with standard samples and then multiple MORB samples were analyzed. The observed IRAT ratios indicate a dominant non-uniaxial anisotropy in the MORBs. Chapters 4 and 5 are archeointensity studies from two data poor <span class="hlt">regions</span> of the world viz., Africa and India. With stringent data selection criteria and well established archeological constraints these datasets provide important constraints on the <span class="hlt">field</span> intensity from 1000 BCE to 1000 CE in Africa and 500 BCE to 1000 CE in India. The African dataset has a higher age resolution than the Indian dataset. The African dataset matches well with the global CALS3k.4 model and shows significant non-axial-dipolar contribution in the <span class="hlt">region</span>. The Indian dataset is not of a similar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790033925&hterms=CONDUCTIVITY+ELECTRIC&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCONDUCTIVITY%2BELECTRIC','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790033925&hterms=CONDUCTIVITY+ELECTRIC&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCONDUCTIVITY%2BELECTRIC"><span id="translatedtitle">Electric <span class="hlt">fields</span> and conductivity in the nighttime E-<span class="hlt">region</span> - A new magnetosphere-ionosphere-atmosphere coupling effect</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Banks, P. M.; Yasuhara, F.</p> <p>1978-01-01</p> <p>Calculations have been made of the effects of intense poleward-directed electric <span class="hlt">fields</span> upon the nighttime ionospheric E-<span class="hlt">region</span>. The results show the Pedersen and Hall conductivities are substantially changed, thereby decreasing the ionospheric electrical load seen by magnetospheric sources. It appears that relatively large electric <span class="hlt">fields</span> can exist in the absence of accompanying large <span class="hlt">field</span>-aligned currents, as long as the underlying ionosphere remains in darkness and/or energetic particle precipitation is absent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2456I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2456I"><span id="translatedtitle"><span class="hlt">Field</span> Significance of Performance Measures in the Context of <span class="hlt">Regional</span> Climate Model Verification</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ivanov, Martin; Warrach-Sagi, Kirsten; Wulfmeyer, Volker</p> <p>2015-04-01</p> <p>The purpose of this study is to rigorously evaluate the skill of dynamically downscaled global climate simulations. We investigate a dynamical downscaling of the ERA-Interim reanalysis using the Weather Research and Forecasting (WRF) model, coupled with the NOAH land surface model within the scope of EURO-CORDEX. WRF has a horizontal resolution of 11° and contains the following physics: the Yonsei university atmospheric boundary layer parameterization, the Morrison two-moment microphysics, the Kain-Fritsch-Eta convection and the Community Atmosphere Model radiation schemes. Daily precipitation is verified over Germany for summer and winter against high-resolution observation data from the German weather service for the first time. The ability of WRF to reproduce the statistical distribution of daily precipitation is evaluated using metrics based on distribution characteristics. Skill against the large-scale ERA-Interim data gives insight into the potential, additional skill of dynamical downscaling. To quantify it, we transform the absolute performance measures to relative skill measures against ERA-Interim. Their <span class="hlt">field</span> significance is rigorously estimated and locally significant <span class="hlt">regions</span> are highlighted. Statistical distributions are better reproduced in summer than in winter. In both seasons WRF is too dry over mountain tops due to underestimated and too rare high and underestimated and too frequent small precipitations. In winter WRF is too wet at windward sides and land-sea transition <span class="hlt">regions</span> due to too frequent weak and moderate precipitation events. In summer it is too dry over land-sea transition <span class="hlt">regions</span> due to underestimated small and too rare moderate precipitations, and too wet in some river valleys due to too frequent high precipitations. Additional skill relative to ERA-Interim is documented for overall measures as well as measures regarding the spread and tails of the statistical distribution, but not regarding mean seasonal precipitation. The added</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJMPB..2940001W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJMPB..2940001W"><span id="translatedtitle">Effects of magnetic <span class="hlt">field</span> intensity on carbon diffusion coefficient in pure iron in γ-Fe temperature <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Yan; Duan, Guosheng; Zhao, Xiang</p> <p>2015-03-01</p> <p>Effects of magnetic <span class="hlt">field</span> intensity on carbon diffusion coefficient in pure iron in the γ-Fe temperature <span class="hlt">region</span> were investigated using carburizing technology. The carbon penetration profiles from the iron surface to interior were measured by <span class="hlt">field</span> emission electron probe microanalyzer. The carbon diffusion coefficient in pure iron carburized with different magnetic <span class="hlt">field</span> intensities was calculated according to the Fick's second law. It was found that the magnetic <span class="hlt">field</span> intensity could obviously affect the carbon diffusion coefficient in pure iron in the γ-Fe temperature <span class="hlt">region</span>, and the carbon diffusion coefficient decreased obviously with the enhancement of magnetic <span class="hlt">field</span> intensity, when the magnetic <span class="hlt">field</span> intensity was higher than 1 T, the carbon diffusion coefficient in <span class="hlt">field</span> annealed specimen was less than half of that of the nonfield annealed specimen, further enhancing the magnetic <span class="hlt">field</span> intensity, the carbon diffusion coefficient basically remains unchanged. The stiffening of lattice due to <span class="hlt">field</span>-induced magnetic ordering was responsible for an increase in activation barrier for jumping carbon atoms. The greater the magnetic <span class="hlt">field</span> intensity, the stronger the inhibiting effect of magnetic <span class="hlt">field</span> on carbon diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFM.B41H..06G&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFM.B41H..06G&link_type=ABSTRACT"><span id="translatedtitle">Carbon mapping of Argentine savannas: Using fractional tree cover to scale from <span class="hlt">field</span> to <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>González-Roglich, M.; Swenson, J. J.</p> <p>2015-12-01</p> <p>Programs which intend to maintain or enhance carbon (C) stocks in natural ecosystems are promising, but require detailed and spatially explicit C distribution models to monitor the effectiveness of management interventions. Savanna ecosystems are significant components of the global C cycle, covering about one fifth of the global land mass, but they have received less attention in C monitoring protocols. Our goal was to estimate C storage across a broad savanna ecosystem using <span class="hlt">field</span> surveys and freely available satellite images. We first mapped tree canopies at 2.5 m resolution with a spatial subset of high resolution panchromatic images to then predict <span class="hlt">regional</span> wall-to-wall tree percent cover using 30-m Landsat imagery and the Random Forests algorithms. We found that a model with summer and winter spectral indices from Landsat, climate and topography performed best. Using a linear relationship between C and % tree cover, we then predicted tree C stocks across the gradient of tree cover, explaining 87 % of the variability. The spatially explicit validation of the tree C model with <span class="hlt">field</span>-measured C-stocks revealed an RMSE of 8.2 tC/ha which represented ~30% of the mean C stock for areas with tree cover, comparable to studies based on more advanced remote sensing methods, such as LiDAR and RADAR. Sample spatial distribution highly affected the performance of the RF models in predicting tree cover, raising concerns regarding the predictive capabilities of the model in areas for which training data is not present. The 50,000 km2 has ~41 Tg C, which could be released to the atmosphere if agricultural pressure intensifies in this semiarid savanna.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/134994','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/134994"><span id="translatedtitle">Modeling the wind-<span class="hlt">fields</span> of accidental releases with an operational <span class="hlt">regional</span> forecast model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Albritton, J.R.; Lee, R.L.; Sugiyama, G.</p> <p>1995-09-11</p> <p>The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC`s operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-<span class="hlt">field</span> scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC`s real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-<span class="hlt">field</span> for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational <span class="hlt">Regional</span> Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1212867H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1212867H"><span id="translatedtitle">Plastic stress <span class="hlt">field</span> in the Alps <span class="hlt">region</span>: comparison of modelling and WSM data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haderka, Peter; Galybin, Alexander N.</p> <p>2010-05-01</p> <p>Modelling of stresses in tectonic plates is usually based on the elastic assumption. However, stress-states in some <span class="hlt">regions</span> of the crust, in particular in mountain areas, can be better described on the basis of limiting equilibrium theories. The current study is aimed to investigate whether plastic Mohr-Coulomb models can be applied for a part of the Eurasian tectonic plate between the lakes Geneva and Constance (the Alps). For this purpose, patterns of stress trajectories are calculated and compared with the WSM data (release 2008) on stress orientations. The problem of stress identification is solved by employing a variant of the Stress Trajectories Element Method (STEM) that also uses the WSM data on stress orientations. Stress magnitudes remain unknown prior to the solution, which differs this research from the conventional approaches. Firstly, discrete data on stress orientations (scattered in the whole <span class="hlt">region</span> between the two lakes) have been converted into continuous one along a chosen boundary. This is necessary in order to specify boundary conditions that are formulated on an open contour in terms of stress orientations and their normal derivatives. The proposed variant of the STEM deals with finite difference formulations for two Cauchy's boundary value problems for identification of the slip lines and the stress trajectories within characteristic triangles. The method also introduces the concept of alternations of the Cauchy's problems for stress trajectories and slip lines, which allows covering a larger area. For given strength parameters (friction angles and cohesion) a unique pattern of stress trajectories is determined. This <span class="hlt">field</span> is further compared against the WSM data available inside the <span class="hlt">region</span>. The comparisons are made for different strength parameters, which allow the best fit to the data. Moreover, because of the fact that the maximum shear stress is governed by the Mohr-Coulomb criterion, the complete stress tensor is found with accuracy of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...818...81J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...818...81J"><span id="translatedtitle">Multi-wavelength Study of a Delta-spot. I. A <span class="hlt">Region</span> of Very Strong, Horizontal Magnetic <span class="hlt">Field</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jaeggli, S. A.</p> <p>2016-02-01</p> <p>Active <span class="hlt">region</span> NOAA 11035 appeared in 2009 December, early in the new solar activity cycle. This <span class="hlt">region</span> achieved a delta sunspot (δ spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and traveled through the penumbra of the largest sunspot in the group. Both visible and infrared imaging spectropolarimetry of the magnetically sensitive Fe i line pairs at 6302 and 15650 Å show large Zeeman splitting in the penumbra between the parasitic umbra and the main sunspot umbra. The polarized Stokes spectra in the strongest <span class="hlt">field</span> <span class="hlt">region</span> display anomalous profiles, and strong blueshifts are seen in an adjacent <span class="hlt">region</span>. Analysis of the profiles is carried out using a Milne-Eddington inversion code capable of fitting either a single magnetic component with stray light or two independent magnetic components to verify the <span class="hlt">field</span> strength. The inversion results show that the anomalous profiles cannot be produced by the combination of two profiles with moderate magnetic <span class="hlt">fields</span>. The largest <span class="hlt">field</span> strengths are 3500-3800 G in close proximity to blueshifts as strong as 3.8 km s-1. The strong, nearly horizontal magnetic <span class="hlt">field</span> seen near the polarity inversion line in this <span class="hlt">region</span> is difficult to understand in the context of a standard model of sunspot magnetohydrostatic equilibrium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.B41A0379J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.B41A0379J"><span id="translatedtitle">From <span class="hlt">field</span> to <span class="hlt">region</span> yield predictions in response to pedo-climatic variations in Eastern Canada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>JÉGO, G.; Pattey, E.; Liu, J.</p> <p>2013-12-01</p> <p>The increase in global population coupled with new pressures to produce energy and bioproducts from agricultural land requires an increase in crop productivity. However, the influence of climate and soil variations on crop production and environmental performance is not fully understood and accounted for to define more sustainable and economical management strategies. <span class="hlt">Regional</span> crop modeling can be a great tool for understanding the impact of climate variations on crop production, for planning grain handling and for assessing the impact of agriculture on the environment, but it is often limited by the availability of input data. The STICS ("Simulateur mulTIdisciplinaire pour les Cultures Standard") crop model, developed by INRA (France) is a functional crop model which has a built-in module to optimize several input parameters by minimizing the difference between calculated and measured output variables, such as Leaf Area Index (LAI). STICS crop model was adapted to the short growing season of the Mixedwood Plains Ecozone using <span class="hlt">field</span> experiments results, to predict biomass and yield of soybean, spring wheat and corn. To minimize the numbers of inference required for <span class="hlt">regional</span> applications, 'generic' cultivars rather than specific ones have been calibrated in STICS. After the calibration of several model parameters, the root mean square error (RMSE) of yield and biomass predictions ranged from 10% to 30% for the three crops. A bit more scattering was obtained for LAI (20%<RMSE<38%). Results indicated so far that one cultivar was enough to describe soybean and spring wheat, while at least two cultivars were required for corn. Flux datasets were also instrumental to select the evapotranspiration function that performed the best in STICS and to make a preliminary verification of the sensitivity of the biomass prediction to climate variations. Using RS data to re-initialize input parameters that are not readily available (e.g. seeding date) is considered an effective way</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.........5A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.........5A"><span id="translatedtitle">Study of the Photospheric Magnetic <span class="hlt">Field</span> and Coronal Emission from Solar Active <span class="hlt">Regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aguilera, Jordan Armando Guerra</p> <p>2016-01-01</p> <p>Solar explosive phenomena (flares and Coronal Mass Ejections, CMEs) are examples of how the most dynamical processes within the heliosphere are interconnected and powered by the Sun. Solar flares originate in active <span class="hlt">regions</span> (AR) -- areas of strong magnetic <span class="hlt">field</span> on the solar surface. The electromagnetic (EM) energy released during flares, along with the often-seen CMEs, propagate through the heliosphere. In the Earth's vicinity, EM radiation and charged particles have the potential to produce unfavorable conditions for humans and technology in space. From many points of view (scientific, operational, economical) it is thus important to understand and try to predict when solar flares and associated eruptive phenomena will occur. This dissertation explores how to best leverage the available observational data to provide predictive information about the future flaring activity. This dissertation consists of two main components: 1) investigation of the photosphere-corona coupling by analyzing photospheric magnetic <span class="hlt">field</span> and coronal data in search for signals or behaviors that precede eruptions; and 2) the combination of existing flare prediction methods in order to develop a novel ensemble prediction. For the first part, the data employed correspond to line-of-sight (LOS) magnetograms from the Helioseismic and Magnetic Imager (HMI) and EUV intensity maps from the Atmospheric Imaging Assembly (AIA), both instruments onboard NASA's Solar Dynamics Observatory (SDO) satellite. Photospheric magnetic <span class="hlt">field</span> and coronal EUV emissions were characterized by measuring the power-law decay of their spatio-temporal spectra and the data statistical associations (auto- and cross-correlations). These measures, calculated with high spatio-temporal resolution, appeared to characterize the AR evolution, provide information about the state of the photospheric plasma, reveal insights into the photospheric conditions for flares, and expose the potential of combining coronal and photospheric</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930057640&hterms=electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3D%2528electric%2Bcurrent%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930057640&hterms=electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3D%2528electric%2Bcurrent%2529"><span id="translatedtitle">The morphology of flare phenomena, magnetic <span class="hlt">fields</span>, and electric currents in active <span class="hlt">regions</span>. III - NOAA active <span class="hlt">region</span> 6233 (1990 August)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>De La Beaujardiere, J.-F.; Canfield, Richard C.; Leka, K. D.</p> <p>1993-01-01</p> <p>We investigate the spatial relationship between vertical electric currents and flare phenomena in NOAA Active <span class="hlt">Region</span> 6233, which was observed 1990, August 28-31 at Mees Solar Observatory. The two flares studied are the 1N/M1.8 flare on August 28, 22:30 UT and the 1N/M1.6 flare on August 29, 20:35 UT. Using Stokes polarimetry we make magnetograms of the <span class="hlt">region</span> and compute the vertical current density. Using H-alpha imaging spectroscopy we identify sites of intense nonthermal electron precipitation or of high coronal pressure. The precipitation in these flares is barely strong enough to be detectable. We find that both precipitation and high pressure tend to occur near vertical currents, but that neither phenomenon is cospatial with current maxima. In contrast with the conclusion of other authors, we argue that these observations do not support a current-interruption model for flares, unless the relevant currents are primarily horizontal. The magnetic morphology and temporal evolution of these flares suggest that an erupting filament model may be relevant, but this model does not explicitly predict the relationship between precipitation, high pressure, and vertical currents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhDT.........2B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhDT.........2B"><span id="translatedtitle">A sub-millimetre survey of dust enshrouded galaxies in the Hubble Deep <span class="hlt">Field</span> <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borys, Colin James Kelvin</p> <p></p> <p>This thesis investigates the emission of sub-millimetre- wave radiation from galaxies in the Hubble Deep <span class="hlt">Field</span> North <span class="hlt">region</span>. The data were obtained from dedicated observing runs from our group and others using the SCUBA camera on the James Clerk Maxwell Telescope. The data were combined using techniques specifically developed here for low signal-to-noise source recovery. The sources found represent over 10% of all cosmological sources SCUBA has detected since it was commissioned. The number of sub-mm galaxies we detect account for a significant fraction of the sub-mm back-ground, and we show that mild extrapolations can reproduce it entirely. We comment on their clustering properties, both with themselves and other high-redshift galaxy types. A multi-wavelength analysis of these galaxies shows that SCUBA sources do not all have similar properties, and are made of a collection including: star-forming radio galaxies; optically invisible objects; active galactic nuclei; and extremely red objects. Reasonable attempts to determine the redshift distribution of the sample show that SCUBA galaxies have a median redshift of around 2, and suggest that the global star formation rate may be dominated by such objects at redshifts beyond about 1. The thesis summarises the current state of extra-galactic sub-mm astronomy, and comments on how new surveys and detectors will allow us to place stronger constraints on the evolution properties of the high-redshift Universe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.V43D..02A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.V43D..02A"><span id="translatedtitle">Symmetrical seismic anisotropy of Mt. Fuji and its interpretations in terms of <span class="hlt">regional</span> stress <span class="hlt">fields</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Araragi, K.; Savage, M. K.; Ohminato, T.; Aoki, Y.</p> <p>2013-12-01</p> <p> objectivity and reliability of the results by suppressing subjective manual criteria. The measured fast directions are consistent at each station and the average of delay times is approximately 0.05 s. We infer that the anisotropic structure is located at shallow depths (<-4km) from the lack of depth dependence of delay times. The fast directions show a radial pattern from the summit. This indicates that the distribution of seismic anisotropy spread symmetrically at least several km from the summit. A few stations far from the summit show deviation from the pattern and the trends of fast directions of those stations are parallel to the NW-SE <span class="hlt">regional</span> stress <span class="hlt">field</span>. Regardless of the increase of seismicity and the Mw5.9 event, the fast directions and delay times did not change significantly. We consider that the lack of temporal change of SWS and spatial distribution of fast polarization directions indicate that symmetric seismic anisotropy in the vicinity of Mt. Fuji is caused mainly by anisotropic structure that is not easily affected by the short-term changes in stress <span class="hlt">field</span>. The radial pattern and deviation from the pattern may suggest the influence of topography superimposed on the <span class="hlt">regional</span> maximum compression as discussed by Nakamura (1977).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19820061309&hterms=electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3D%2528electric%2Bcurrent%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19820061309&hterms=electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3D%2528electric%2Bcurrent%2529"><span id="translatedtitle">Initial results on the correlation between the magnetic and electric <span class="hlt">fields</span> observed from the DE-2 satellite in the <span class="hlt">field</span>-aligned current <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sugiura, M.; Maynard, N. C.; Farthing, W. H.; Heppner, J. P.; Ledley, B. G.; Cahill, L. J., Jr.</p> <p>1982-01-01</p> <p>Initial results of the electric and magnetic <span class="hlt">field</span> observations from the DE-2 satellite show a remarkably good correlation between the north-south component of the electric <span class="hlt">field</span> and the east-west component of the magnetic <span class="hlt">field</span> in many passes of the <span class="hlt">field</span>-aligned current <span class="hlt">regions</span>. For a dayside cusp pass on August 15, 1981 the coefficient of correlation between these components was 0.996. A preliminary inspection of the available data from the first 6 months of the DE operation indicates that the similarity between the electric and magnetic <span class="hlt">field</span> signatures of the <span class="hlt">field</span>-aligned currents is a commonly observed feature at all local times. This high correlation is interpreted to be an indication that the closure of the <span class="hlt">field</span>-aligned current is essentially meridional. When the correlation between these components is not good, the closure current is likely to be flowing along the auroral belt. When the correlation between the electric and magnetic <span class="hlt">fields</span> is high, it is possible to estimate the height-integrated Pedersen conductivity from the observed <span class="hlt">field</span> components.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006ThApC..86..215F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006ThApC..86..215F"><span id="translatedtitle"><span class="hlt">Regional</span> model simulation of summer rainfall over the Philippines: Effect of choice of driving <span class="hlt">fields</span> and ocean flux schemes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Francisco, R. V.; Argete, J.; Giorgi, F.; Pal, J.; Bi, X.; Gutowski, W. J.</p> <p>2006-09-01</p> <p>The latest version of the Abdus Salam International Centre for Theoretical Physics (ICTP) <span class="hlt">regional</span> model RegCM is used to investigate summer monsoon precipitation over the Philippine archipelago and surrounding ocean waters, a <span class="hlt">region</span> where <span class="hlt">regional</span> climate models have not been applied before. The sensitivity of simulated precipitation to driving lateral boundary conditions (NCEP and ERA40 reanalyses) and ocean surface flux scheme (BATS and Zeng) is assessed for 5 monsoon seasons. The ability of the RegCM to simulate the spatial patterns and magnitude of monsoon precipitation is demonstrated, both in response to the prominent large scale circulations over the <span class="hlt">region</span> and to the local forcing by the physiographical features of the Philippine islands. This provides encouraging indications concerning the development of a <span class="hlt">regional</span> climate modeling system for the Philippine <span class="hlt">region</span>. On the other hand, the model shows a substantial sensitivity to the analysis <span class="hlt">fields</span> used for lateral boundary conditions as well as the ocean surface flux schemes. The use of ERA40 lateral boundary <span class="hlt">fields</span> consistently yields greater precipitation amounts compared to the use of NCEP <span class="hlt">fields</span>. Similarly, the BATS scheme consistently produces more precipitation compared to the Zeng scheme. As a result, different combinations of lateral boundary <span class="hlt">fields</span> and surface ocean flux schemes provide a good simulation of precipitation amounts and spatial structure over the <span class="hlt">region</span>. The response of simulated precipitation to using different forcing analysis <span class="hlt">fields</span> is of the same order of magnitude as the response to using different surface flux parameterizations in the model. As a result it is difficult to unambiguously establish which of the model configurations is best performing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFMIN21B1181R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFMIN21B1181R"><span id="translatedtitle">Seafloor Sounding in Polar and Remote <span class="hlt">Regions</span> (SSPARR) Project - Initial <span class="hlt">Field</span> Trials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rognstad, M. R.; Anderson, R. M.; Chayes, D. N.; Mayer, L. A.</p> <p>2005-12-01</p> <p>The Seafloor Sounding in Polar and Remote <span class="hlt">Regions</span> (SSPARR) project, under sponsorship of the National Science Foundation, is developing the capability to acquire autonomous bathymetric observations in remote <span class="hlt">regions</span>, by means of an inexpensive (expendable) depth sounder supported by a GPS navigation receiver and global satellite telemetry capability. The depth sounder component operates at 12 kHz and is packaged in a watertight housing suspended approximately 10 meters below the water surface. A sonar transducer is mounted on the bottom of the cylindrical sounder housing; electronics and batteries for powering the sounder are contained in the housing. A cable carrying data and control signals connects to the surface package, which houses the telemetry and control system, GPS receiver, and batteries. This surface package would include flotation, so the SSPARR system could be deployed as a drifting buoy or installed in suitable ice floes. The depth sounder electronics utilize a Freescale Semiconductor DSP56309 digital signal processor to synthesize the transmitted signal, and to acquire and process the acoustic echoes. The signal processing involves quadrature detection at 12 kHz, matched filtering and decimation; data are acquired for intervals ranging from 125 milliseconds to 8 seconds, depending upon the desired range. At present, the sounder software records data for the entire acquisition interval; this raw data is being used to test bottom detection algorithms. In order to minimize the likelihood that a mid-water scattering layer or ice keel mask the true bottom reflection, the desired algorithm will report multiple reflections to the control and telemetry processor when they are detected. The bottom detection function has been evaluated with <span class="hlt">field</span> trial data will be incorporated into the final sounder design. A test of the sounder transducer was conducted in May 2004 aboard the R/V Kilo Moana, using electronics from the University of Hawaii's Integrated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.447L..21Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.447L..21Z"><span id="translatedtitle">Radiation <span class="hlt">fields</span> of intermediate-age stellar populations with binaries as ionizing sources of H II <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, F.; Li, L.; Cheng, L.; Wang, L.; Kang, X.; Zhuang, Y.; Han, Z.</p> <p>2015-02-01</p> <p>Radiation <span class="hlt">fields</span> emitted by O- and B-type stars or young stellar populations (SPs) are generally considered as significant central ionizing sources (CISs) of classic H II <span class="hlt">regions</span>. In our previous studies, we showed that the inclusion of binary interactions in stellar population synthesis models can significantly increase the ultraviolet spectrum hardness and the number of ionizing photons of intermediate-age (IA) SPs (7 ≲ log(t/yr) ≲ 8). In this work, we present photoionization models of H II <span class="hlt">regions</span> ionized by radiation <span class="hlt">fields</span> emitted by IA SPs, including binary systems, and show that these <span class="hlt">fields</span> are in theory possible candidates for significant CISs of classic H II <span class="hlt">regions</span>. When radiation <span class="hlt">fields</span> of IA SPs comprising binary systems are used as the CISs of classic H II <span class="hlt">regions</span>, the theoretical strengths of a number of lines (such as [O III] λ4959', [S II] λ6716', etc.), which are weaker than observations, are increased; the border or selection-criterion lines between star-forming galaxies and active galactic nuclei (AGNs) in the diagnostic diagrams (for example, [N II] λ6583/Hα versus [O III] λ5007/Hβ), move into the <span class="hlt">region</span> occupied originally by AGNs; and the He II λ1640 line, observed in Lyman break and high-redshift gravitationally lensed galaxies, also can be produced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.4103Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.4103Z"><span id="translatedtitle">First in situ evidence of electron pitch angle scattering due to magnetic <span class="hlt">field</span> line curvature in the Ion diffusion <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Y. C.; Shen, C.; Marchaudon, A.; Rong, Z. J.; Lavraud, B.; Fazakerley, A.; Yao, Z.; Mihaljcic, B.; Ji, Y.; Ma, Y. H.; Liu, Z. X.</p> <p>2016-05-01</p> <p>Theory predicts that the first adiabatic invariant of a charged particle may be violated in a <span class="hlt">region</span> of highly curved <span class="hlt">field</span> lines, leading to significant pitch angle scattering for particles whose gyroradius are comparable to the radius of the magnetic <span class="hlt">field</span> line curvature. This scattering generates more isotropic particle distribution functions, with important impacts on the presence or absence of plasma instabilities. Using magnetic curvature analysis based on multipoint Cluster spacecraft observations, we present the first investigation of magnetic curvature in the vicinity of an ion diffusion <span class="hlt">region</span> where reconnected <span class="hlt">field</span> lines are highly curved. Electrons at energies > 8 keV show a clear pitch angle ordering between bidirectional and trapped distribution in surrounding <span class="hlt">regions</span>, while we show that in the more central part of the ion diffusion <span class="hlt">region</span> electrons above such energies become isotropic. By contrast, colder electrons (~1 keV) retain their bidirectional character throughout the diffusion <span class="hlt">regions</span>. The calculated adiabatic parameter K2 for these electrons is in agreement with theory. This study provides the first observational evidence for particle pitch angle scattering due to magnetic <span class="hlt">field</span> lines with well characterized curvature in a space plasma.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007ApJ...666..794F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007ApJ...666..794F"><span id="translatedtitle">Integral <span class="hlt">Field</span> Spectroscopy of the Extended Emission-Line <span class="hlt">Region</span> of 4C 37.43</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fu, Hai; Stockton, Alan</p> <p>2007-09-01</p> <p>We present Gemini integral <span class="hlt">field</span> spectroscopy and Keck II long-slit spectroscopy of the extended emission-line <span class="hlt">region</span> (EELR) around the quasar 4C 37.43. The velocity structure of the ionized gas is complex and cannot be explained globally by a simple dynamical model. The spectra from the clouds are inconsistent with shock or ``shock + precursor'' ionization models, but they are consistent with photoionization by the quasar nucleus. The best-fit photoionization model requires a low-metallicity [12+log(O/H)<~8.7] two-phase medium, consisting of a matter-bounded diffuse component with a unity filling factor (N~1 cm-3, T~15,000 K), in which are embedded small, dense clouds (N~400 cm-3, T~104 K). The high-density clouds are transient and can be regenerated through compressing the diffuse medium by low-speed shocks (VS<~100 km s-1). Our photoionization model gives a total mass for the ionized gas of about 3×1010 Msolar, and the total kinetic energy implied by this mass and the observed velocity <span class="hlt">field</span> is ~2×1058 erg. The fact that luminous EELRs are confined to steep-spectrum radio-loud QSOs, yet show no morphological correspondence to the radio jets, suggests that the driving force producing the 4C 37.43 EELR was a roughly spherical blast wave initiated by the production of the jet. That such a mechanism seems capable of ejecting a mass comparable to that of the total interstellar medium of the Milky Way suggests that ``quasar-mode'' feedback may indeed be an efficient means of regulating star formation in the early universe. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G23B0919E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G23B0919E"><span id="translatedtitle">The EarthScope Plate Boundary Observatory Alaska <span class="hlt">Region</span>: Highlights from the 2012 Summer <span class="hlt">Field</span> Season</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Enders, M.; Bierma, R. M.; Boyce, E. S.; Willoughby, H.; Fend, M.; Feaux, K.</p> <p>2012-12-01</p> <p>UNAVCO has now completed its fourth year of operation and maintenance of the 138 continuous GPS stations, 12 tiltmeters and 31 data communications relays that comprise the Alaska <span class="hlt">region</span> of the EarthScope Plate Boundary Observatory (PBO). The successful operation of the autonomous GPS and tiltmeter network in Alaska continues to be a challenge, because of logistics, weather, and other difficulties related to working in Alaska. PBO engineers continue to work on network enhancements to make the stations more robust, while improving overall data quality and station uptime to better serve the EarthScope science community. In the summer of 2012, PBO engineers completed maintenance activities in Alaska, which resulted in a 95% operational status for the Alaska network within PBO. PBO engineers completed a total of 87 maintenance visits in the summer of FY2012, including 62 routine maintenance and 25 unscheduled maintenance visits to GPS and data communications stations. We present a number of highlights and accomplishments from the PBO 2012 summer <span class="hlt">field</span> season in Alaska, for example the deployment of a newly designed methanol fuel cell at AV35, a critical station that serves as the main repeater for the real time network on Unimak Island. In addition, PBO engineers also completed the installation of three Inmarsat BGAN terminals for data telemetry following successful testing at AC60 Shemya. Lastly, PBO engineers completed scheduled battery replacements at most of the PBO stations on Unimak Island, in collaboration with the USGS/Alaska Volcano Observatory. In addition to routine maintenance and planned station improvements to sites in Alaska, numerous critical repairs were made at stations on Unimak Island and elsewhere to ensure that the PBO network continues to function well and continues to meet the requirements stipulated by the NSF. We also present some of the station failures unique to Alaska, which we encountered during the course of the 2012 <span class="hlt">field</span> season, as well</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/538600','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/538600"><span id="translatedtitle">New Features of Time Domain Electric-<span class="hlt">Field</span> Structures in the Auroral Acceleration <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mozer, F.S.; Ergun, R.; Temerin, M.; Cattell, C.; Dombeck, J.; Wygant, J.</p> <p>1997-08-01</p> <p>The Polar Satellite carries the first three-axis electric <span class="hlt">field</span> detector flown in the magnetosphere. Its direct measurement of electric <span class="hlt">field</span> components perpendicular and parallel to the local magnetic <span class="hlt">field</span> has revealed new classes and features of electric <span class="hlt">field</span> structures associated with the plasma acceleration that produces discrete auroras and that populates the magnetosphere with plasma of ionospheric origin. These structures, associated with the hydrogen ion cyclotron mode, include very large solitary waves, spiky <span class="hlt">field</span> structures, wave envelopes of parallel electric <span class="hlt">fields</span>, and very large amplitude, nonlinear, coherent ion cyclotron waves. {copyright} {ital 1997} {ital The American Physical Society}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SpWea...8.5002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SpWea...8.5002M"><span id="translatedtitle">Spectral analysis of pipe-to-soil potentials with variations of the Earth's magnetic <span class="hlt">field</span> in the Australian <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marshall, R. A.; Waters, C. L.; Sciffer, M. D.</p> <p>2010-05-01</p> <p>Long, steel pipelines used to transport essential resources such as gas and oil are potentially vulnerable to space weather. In order to inhibit corrosion, the pipelines are usually coated in an insulating material and maintained at a negative electric potential with respect to Earth using cathodic protection units. During periods of enhanced geomagnetic activity, potential differences between the pipeline and surrounding soil (referred to as pipe-to-soil potentials (PSPs)) may exhibit large voltage swings which place the pipeline outside the recommended "safe range" and at an increased risk of corrosion. The PSP variations result from the "geoelectric" <span class="hlt">field</span> at the Earth's surface and associated geomagnetic <span class="hlt">field</span> variations. Previous research investigating the relationship between the surface geoelectric <span class="hlt">field</span> and geomagnetic source <span class="hlt">fields</span> has focused on the high-latitude <span class="hlt">regions</span> where line currents in the ionosphere E <span class="hlt">region</span> are often the assumed source of the geomagnetic <span class="hlt">field</span> variations. For the Australian <span class="hlt">region</span> Sq currents also contribute to the geomagnetic <span class="hlt">field</span> variations and provide the major contribution during geomagnetic quiet times. This paper presents the results of a spectral analysis of PSP measurements from four pipeline networks from the Australian <span class="hlt">region</span> with geomagnetic <span class="hlt">field</span> variations from nearby magnetometers. The pipeline networks extend from Queensland in the north of Australia to Tasmania in the south and provide PSP variations during both active and quiet geomagnetic conditions. The spectral analyses show both consistent phase and amplitude relationships across all pipelines, even for large separations between magnetometer and PSP sites and for small-amplitude signals. Comparison between the observational relationships and model predictions suggests a method for deriving a geoelectric <span class="hlt">field</span> proxy suitable for indicating PSP-related space weather conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021369&hterms=electric+current&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2528electric%2Bcurrent%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021369&hterms=electric+current&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2528electric%2Bcurrent%2529"><span id="translatedtitle">Electric <span class="hlt">fields</span> and <span class="hlt">field</span>-aligned currents in polar <span class="hlt">regions</span> of the solar corona: 3-D MHD consideration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pisanko, Yu. V.</p> <p>1995-01-01</p> <p>The calculation of the solar rotation electro-dynamical effects in the near-the-Sun solar wind seems more convenient from the non-inertial corotating reference frame. This implies some modification of the 3-D MHD equations generally on the base of the General Theory of Relativity. The paper deals with the search of stationary (in corotating non-inertial reference frame) solutions of the modified 3-D MHD equations for the in near-the-Sun high latitude sub-alfvenic solar wind. The solution is obtained requiring electric <span class="hlt">fields</span> and <span class="hlt">field</span>-aligned electric currents in the high latitude near-the-Sun solar wind. Various scenario are explored self-consistently via a number of numerical experiments. The analogy with the high latitude Earth's magnetosphere is used for the interpretation of the results. Possible observational manifestations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM23A2534C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM23A2534C"><span id="translatedtitle">The dynamics of <span class="hlt">region</span> 1 <span class="hlt">field</span>-aligned currents during periods of dayside and nightside reconnection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clausen, L. B. N.; Ruohoniemi, J. M.; Baker, J. B. H.; Milan, S. E.; Coxon, J.; Anderson, B. J.</p> <p>2015-12-01</p> <p>We use current density data from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) to identify the location of maximum <span class="hlt">region</span> 1 current at all magnetic local times. We term this location the R1 oval. Comparing the R1 oval location with particle precipitation boundaries identified in DMSP data, we find that the R1 oval is located on average within 1° of particle signatures associated with the open/closed <span class="hlt">field</span> line boundary (OCB) across dayside and nightside MLTs. We hence conclude that the R1 oval can be used as a proxy for the location of the OCB. Studying the amount of magnetic flux enclosed by the R1 oval during the substorm cycle, we find that the R1 oval flux is well organized by it: during the growth phase the R1 oval location moves equatorward as the amount of magnetic flux increases whereas after substorm expansion phase onset significant flux closure occurs as the R1 current location retreats to higher latitudes. For about 15 minutes after expansion phase onset the amount of open magnetic flux continues to increase indicating that dayside reconnection dominates over nightside reconnection. In the current density data we find evidence of the substorm current wedge and also show that the dayside R1 currents are stronger than their nightside counterpart during the substorm growth phase whereas after expansion phase onset the nightside R1 currents dominate. Our observations of the current distribution and OCB movement during the substorm cycle are in excellent agreement with the expanding/contracting polar cap paradigm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A13K3322M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A13K3322M"><span id="translatedtitle">Coastal Downscaling Experiments: Can CESM <span class="hlt">Fields</span> Successfully Force <span class="hlt">Regional</span> Coastal Ocean Simulations with Strong Freshwater Forcing?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>MacCready, P.; Bryan, F.; Tseng, Y. H.; Whitney, M. M.</p> <p>2014-12-01</p> <p>The coastal ocean accounts for about half of the global fish harvest, but is poorly resolved in global climate models (a one-degree grid barely sees the continental shelf). Moreover, coastal ocean circulation is strongly modified by river freshwater sources, often coming from estuarine systems that are completely unresolved in the coarse grid. River freshwater input in CESM is added in a practical but ad hoc way, by imposing a surface salinity sink over a <span class="hlt">region</span> of the ocean approximating the plume area of a given river. Here we present results from a series of model experiments using a high-resolution (1.5 km) ROMS model of the NE Pacific, including the Columbia River and the inland waters of Puget Sound. The base model does multi-year hindcasts using the best available sources of atmospheric (MM5/WRF), ocean (NCOM), river (USGS), and tidal forcing. It has been heavily validated against observations of all sorts, and performs well, so it is an ideal test bed for downscaling experiments. The model framework also does biogeochemistry, including oxygen, and carbon chemistry is being added to make forecasts of Ocean Acidification.This high-resolution ROMS model is systematically run in downscaling experiments for the year 2005 with combinations of CESM forcing (CAM, POP, and rivers) swapped in. Skill is calculated using observations. It is found that the runs with CESM forcing generally retain much of the skill of the base model. A compact metric of response to freshwater forcing is used, which is the mechanical energy required to destratify a shallow coastal volume. This, along with the average temperature and salinity of the volume, are used to characterize and compare runs, including the original CESM-POP <span class="hlt">fields</span>. Finally the model is run with projected CESM simulation forcing at the end of 21st century based on a set of RCP scenarios, and the compact metrics are used to quantify differences from 2005.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014PhDT.......127S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014PhDT.......127S&link_type=ABSTRACT"><span id="translatedtitle">Investigating the Seismicity and Stress <span class="hlt">Field</span> of the Truckee -- Lake Tahoe <span class="hlt">Region</span>, California -- Nevada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seaman, Tyler</p> <p></p> <p>The Lake Tahoe basin is located in a transtensional environment defined by east-dipping range--bounding normal faults, northeast--trending sinistral, and northwest-trending dextral strike-slip faults in the northern Walker Lane deformation belt. This <span class="hlt">region</span> accommodates as much as 10 mm/yr of dextral shear between the Sierra Nevada and Basin and Range proper, or about 20% of Pacific-North American plate motion. There is abundant seismicity north of Lake Tahoe through the Truckee, California <span class="hlt">region</span> as opposed to a lack of seismicity associated with the primary normal faults in the Tahoe basin (i.e., West Tahoe fault). This seismicity study is focused on the structural transition zone from north-striking east-dipping Sierran Range bounding normal faults into the northern Walker Lane right-lateral strike-slip domain. Relocations of earthquakes between 2000-2013 are performed by initially applying HYPOINVERSE mean sea level datum and station corrections to produce higher confidence absolute locations as input to HYPODD. HYPODD applies both phase and cross-correlation times for a final set of 'best' event relocations. Relocations of events in the upper brittle crust clearly align along well-imaged, often intersecting, high-angle structures of limited lateral extent. In addition, the local stress <span class="hlt">field</span> is modeled from 679 manually determined short-period focal mechanism solutions, between 2000 and 2013, located within a fairly dense local seismic network. Short-period focal mechanisms were developed with the HASH algorithm and moment tensor solutions using long-period surface waves and the MTINV code. Resulting solutions show a 9:1 ratio of strike-slip to normal mechanisms in the transition zone study area. Stress inversions using the application SATSI (USGS Spatial And Temporal Stress Inversion) generally show a T-axis oriented primarily E-W that also rotates about 30 degrees counterclockwise, from a WNW-ESE trend to ENE-WSW, moving west to east across the California</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4477762','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4477762"><span id="translatedtitle"><span class="hlt">Regional</span> lymph node radiotherapy in breast cancer: single anterior supraclavicular <span class="hlt">field</span> vs. two anterior and posterior opposed supraclavicular <span class="hlt">fields</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Houshyari, Mohammad; Kashi, Amir Shahram Yousefi; Varaki, Sakineh Soleimani; Rakhsha, Afshin; Blookat, Eftekhar Rajab</p> <p>2015-01-01</p> <p>Background: The treatment of lymph nodes engaged in breast cancer with radiotherapy leads to improved locoregional control and enhanced survival rates in patients after surgery. The aim of this study was to compare two treatment techniques, namely single anterior posterior (AP) supraclavicular <span class="hlt">field</span> with plan depth and two anterior and posterior opposed (AP/PA) supraclavicular <span class="hlt">fields</span>. In the study, we also examined the relationships between the depth of supraclavicular lymph nodes (SCLNs) and the diameter of the wall of the chest and body mass index (BMI). Methods: Forty patients with breast cancer were analyzed using computed tomography (CT) scans. In planning target volume (PTV), the SCLNs and axillary lymph nodes (AXLNs) were contoured, and, with the attention to PTV, supraclavicular (SC) depth was measured. The dosage that reached the aforementioned lymph nodes and the level of hot spots were investigated using two treatment methods, i.e., 1) AP/PA and 2) AP with three-dimensional (3D) planning. Each of these methods was analyzed using the program Isogray for the 6 MV compact accelerator, and the diameter of the wall of the chest was measured using the CT scan at the center of the SC <span class="hlt">field</span>. Results: Placing the plan such that 95% of the target volume with 95% or greater of the prescribed dose of 50 Gy (V95) had ≥95% concordance in both treatment techniques. According to the PTV, the depth of SCLNs and the diameter of the wall of the chest were 3–7 and 12–21cm, respectively. Regression analysis showed that the mean SC depth (the mean Plan depth) and the mean diameter of the wall of the chest were related directly to BMI (p<0.0001, adjusted R2=0.67) and (p<0.0001, adjusted R2=0.71), respectively. Conclusion: The AP/PA treatment technique was a more suitable choice of treatment than the AP <span class="hlt">field</span>, especially for overweight and obese breast cancer patients. However, in the AP/PA technique, the use of a single-photon, low energy (6 MV) caused more hot spots</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApJ...780...55J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApJ...780...55J"><span id="translatedtitle">Formation and Eruption of an Active <span class="hlt">Region</span> Sigmoid. I. A Study by Nonlinear Force-free <span class="hlt">Field</span> Modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Chaowei; Wu, S. T.; Feng, Xueshang; Hu, Qiang</p> <p>2014-01-01</p> <p>We present a comprehensive study of the formation and eruption of an active <span class="hlt">region</span> (AR) sigmoid in AR 11283. To follow the quasi-static evolution of the coronal magnetic <span class="hlt">field</span>, we reconstruct a time sequence of static <span class="hlt">fields</span> using a recently developed nonlinear force-free <span class="hlt">field</span> model constrained by vector magnetograms. A detailed analysis of the <span class="hlt">fields</span> compared with observations suggests the following scenario for the evolution of the <span class="hlt">region</span>. Initially, a new bipole emerges into the negative polarity of a preexisting bipolar AR, forming a null-point topology between the two flux systems. A weakly twisted flux rope (FR) is then built up slowly in the embedded core <span class="hlt">region</span>, largely through flux cancellation, forming a bald patch separatrix surface (BPSS). The FR grows gradually until its axis runs into a torus instability (TI) domain, and the BPSS also develops a full S-shape. The combined effects of the TI-driven expansion of the FR and the line tying at the BP tear the FR into two parts with the upper portion freely expelled and the lower portion remaining behind the postflare arcades. This process dynamically perturbs the BPSS and results in the enhanced heating of the sigmoid and the rope. The accelerated expansion of the upper-portion rope strongly pushes its envelope flux near the null point and triggers breakout reconnection at the null, which further drives the eruption. We discuss the important implications of these results for the formation and disruption of the sigmoid <span class="hlt">region</span> with an FR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1637A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1637A"><span id="translatedtitle">Analysis of the disturbed electric <span class="hlt">field</span> effects in the sporadic E-layers at equatorial and low latitude <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Araujo Resende, Laysa Cristina; Moro, Juliano; Denardini, Clezio Marcos; Carrasco, Alexander J.; Batista, Paulo; Chen, Sony Su; Batista, Inez S.; Andrioli, Vania Fatima</p> <p>2016-07-01</p> <p>In the present work we analyze the disturbed electric <span class="hlt">field</span> effects in the sporadic E-layers at equatorial <span class="hlt">regions</span>, Jicamarca (11.57°S, 76.52°O, I: -2°) and São Luís (2°S, 44° O, I: -2.3°), and at low latitude <span class="hlt">regions</span>, Fortaleza (3.9°S, 38.45°O, I: -9°) and Cachoeira Paulista (22.42°S, 45°O, I: -15°). We have conducted a deep analysis to investigate these effects using a theoretical model for the ionospheric E <span class="hlt">region</span>, called MIRE. This model is able to simulate the Es layers taking into account the E <span class="hlt">region</span> winds and electric <span class="hlt">fields</span>. It calculates the densities for the main molecular (NO^{+}, O_{2}^{+}, N_{2}^{+}) and metallic ions (Fe^{+}, Mg^{+}) by solving the continuity and momentum equations for each species. The main purpose of this analysis is to verify the disturbed electric <span class="hlt">fields</span> role in the occurrence or disruption of Es layers through simulations. The analysis show that the Es layer formation and dynamics can be influenced by the prompt penetration electric <span class="hlt">fields</span> that occur during magnetic disturbances. Therefore, the simulations present interesting results that helps to improve the understanding of Es layer behavior during the disturbed periods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22016129','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22016129"><span id="translatedtitle">EVOLUTION OF MAGNETIC <span class="hlt">FIELD</span> AND ENERGY IN A MAJOR ERUPTIVE ACTIVE <span class="hlt">REGION</span> BASED ON SDO/HMI OBSERVATION</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sun Xudong; Hoeksema, J. Todd; Liu, Yang; Hayashi, Keiji; Wiegelmann, Thomas; Thalmann, Julia; Chen Qingrong</p> <p>2012-04-01</p> <p>We report the evolution of the magnetic <span class="hlt">field</span> and its energy in NOAA active <span class="hlt">region</span> 11158 over five days based on a vector magnetogram series from the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamic Observatory (SDO). Fast flux emergence and strong shearing motion led to a quadrupolar sunspot complex that produced several major eruptions, including the first X-class flare of Solar Cycle 24. Extrapolated nonlinear force-free coronal <span class="hlt">fields</span> show substantial electric current and free energy increase during early flux emergence near a low-lying sigmoidal filament with a sheared kilogauss <span class="hlt">field</span> in the filament channel. The computed magnetic free energy reaches a maximum of {approx}2.6 Multiplication-Sign 10{sup 32} erg, about 50% of which is stored below 6 Mm. It decreases by {approx}0.3 Multiplication-Sign 10{sup 32} erg within 1 hr of the X-class flare, which is likely an underestimation of the actual energy loss. During the flare, the photospheric <span class="hlt">field</span> changed rapidly: the horizontal <span class="hlt">field</span> was enhanced by 28% in the core <span class="hlt">region</span>, becoming more inclined and more parallel to the polarity inversion line. Such change is consistent with the conjectured coronal <span class="hlt">field</span> 'implosion' and is supported by the coronal loop retraction observed by the Atmospheric Imaging Assembly (AIA). The extrapolated <span class="hlt">field</span> becomes more 'compact' after the flare, with shorter loops in the core <span class="hlt">region</span>, probably because of reconnection. The coronal <span class="hlt">field</span> becomes slightly more sheared in the lowest layer, relaxes faster with height, and is overall less energetic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SoPh..289.3549B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SoPh..289.3549B"><span id="translatedtitle">The Helioseismic and Magnetic Imager (HMI) Vector Magnetic <span class="hlt">Field</span> Pipeline: SHARPs - Space-Weather HMI Active <span class="hlt">Region</span> Patches</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bobra, M. G.; Sun, X.; Hoeksema, J. T.; Turmon, M.; Liu, Y.; Hayashi, K.; Barnes, G.; Leka, K. D.</p> <p>2014-09-01</p> <p>A new data product from the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) called Space-weather HMI Active <span class="hlt">Region</span> Patches ( SHARPs) is now available. SDO/HMI is the first space-based instrument to map the full-disk photospheric vector magnetic <span class="hlt">field</span> with high cadence and continuity. The SHARP data series provide maps in patches that encompass automatically tracked magnetic concentrations for their entire lifetime; map quantities include the photospheric vector magnetic <span class="hlt">field</span> and its uncertainty, along with Doppler velocity, continuum intensity, and line-of-sight magnetic <span class="hlt">field</span>. Furthermore, keywords in the SHARP data series provide several parameters that concisely characterize the magnetic-<span class="hlt">field</span> distribution and its deviation from a potential-<span class="hlt">field</span> configuration. These indices may be useful for active-<span class="hlt">region</span> event forecasting and for identifying <span class="hlt">regions</span> of interest. The indices are calculated per patch and are available on a twelve-minute cadence. Quick-look data are available within approximately three hours of observation; definitive science products are produced approximately five weeks later. SHARP data are available at jsoc.stanford.edu and maps are available in either of two different coordinate systems. This article describes the SHARP data products and presents examples of SHARP data and parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JPSJ...85i4501Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JPSJ...85i4501Y&link_type=ABSTRACT"><span id="translatedtitle">Variation of Magnetic Fluctuation due to Gas Puffing in Edge <span class="hlt">Region</span> of Reversed-<span class="hlt">Field</span> Pinch Plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yambe, Kiyoyuki; Hirano, Yoichi; Sakakita, Hajime; Koguchi, Haruhisa</p> <p>2016-09-01</p> <p>We measured the variation of magnetic and electrostatic fluctuations observed during the gas puffing in the edge <span class="hlt">region</span> of the toroidal pinch experiment-reversed experiment (TPE-RX) reversed-<span class="hlt">field</span> pinch plasma. In the short period in which the electron density increased slowly just after the gas puffing, the confinement of fast electrons in the core <span class="hlt">region</span> was maintained by the decrease in the fast radial magnetic fluctuation with the deepening of the reversal of the toroidal <span class="hlt">field</span>. During the following period in which the electron density increased rapidly, the radial gradient of electron density decreased, and the loss of fast electrons from the core <span class="hlt">region</span> increased owing to the increase in the toroidal and radial magnetic fluctuations in the high-frequency band, although the poloidal magnetic fluctuation decreased. Therefore, the confinement of fast electrons would be maintained by keeping the radial gradient of plasma thermal pressure with a moderate neutral particle supply of small quantity in a short time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020067741','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020067741"><span id="translatedtitle">X-Ray Properties of Lyman Break Galaxies in the Hubble Deep <span class="hlt">Field</span> North <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nandra, K.; Mushotzky, R. F.; Arnaud, K.; Steidel, C. C.; Adelberger, K. L.; Gardner, J. P.; Teplitz, H. I.; Windhorst, R. A.; White, Nicholas E. (Technical Monitor)</p> <p>2002-01-01</p> <p>We describe the X-ray properties of a large sample of z approximately 3 Lyman Break Galaxies (LBGs) in the <span class="hlt">region</span> of the Hubble Deep <span class="hlt">Field</span> North, derived from the 1 Ms public Chandra observation. Of our sample of 148 LBGs, four are detected individually. This immediately gives a measure of the bright AGN (active galactic nuclei) fraction in these galaxies of approximately 3 per cent, which is in agreement with that derived from the UV (ultraviolet) spectra. The X-ray color of the detected sources indicates that they are probably moderately obscured. Stacking of the remainder shows a significant detection (6 sigma) with an average luminosity of 3.5 x 10(exp 41) erg/s per galaxy in the rest frame 2-10 keV band. We have also studied a comparison sample of 95 z approximately 1 "Balmer Break" galaxies. Eight of these are detected directly, with at least two clear AGN based on their high X-ray luminosity and very hard X-ray spectra respectively. The remainder are of relatively low luminosity (< 10(exp 42) erg/s, and the X-rays could arise from either AGN or rapid star-formation. The X-ray colors and evidence from other wavebands favor the latter interpretation. Excluding the clear AGN, we deduce a mean X-ray luminosity of 6.6 x 10(exp 40) erg/s, a factor approximately 5 lower than the LBGs. The average ratio of the UV and X-ray luminosities of these star forming galaxies L(sub UV)/L (sub X), however, is approximately the same at z = 1 as it is at z = 3. This scaling implies that the X-ray emission follows the current star formation rate, as measured by the UV luminosity. We use our results to constrain the star formation rate at z approximately 3 from an X-ray perspective. Assuming the locally established correlation between X-ray and far-IR (infrared) luminosity, the average inferred star formation rate in each Lyman break galaxy is found to be approximately 60 solar mass/yr, in excellent agreement with the extinction-corrected UV estimates. This provides an external</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1126581','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1126581"><span id="translatedtitle">Direct, spectroscopic measurement of electric <span class="hlt">fields</span> in a plasma-RF antenna interaction <span class="hlt">region</span> in Tore Supra</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Klepper, C Christopher; Hillis, Donald Lee; Isler, Ralph C; Hillairet, J.; Martin, E. H.; Colas, L.; Ekedahl, A.; Goniche, M.; Lotte, Ph.; Colledani, G.; Martin, V.; Panayotis, Stephanie; Pegourie, B.; Harris, Jeffrey H</p> <p>2013-01-01</p> <p>Balmer-series spectral line profiles of deuterium emission near a lower-hybrid (3.7 GHz) wave, high power (1-4 MW) launcher were measured with high-spectral resolution in the Tore Supra tokamak and fitted to an atomic physics model which includes both Zeeman and dynamic Stark effects. The magnetic <span class="hlt">field</span> is static and the electric <span class="hlt">field</span> is assumed to be monochromatic at 3.7 GHz. The determined strength and direction of the high-frequency electric <span class="hlt">field</span> is found to be in good agreement with the results of a simulation that computes the propagation of these lower hybrid waves into the plasma in the <span class="hlt">region</span> around the launch antenna and specifically in the <span class="hlt">region</span> of estimated peak emission contributing to the measurement. This agreement indicates feasibility for the use of dynamic Stark effect spectroscopy to study interaction at the plasma antenna interactions in a fusion plasma environment. (C) 2013 Elsevier B. V. All rights reserved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22486415','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22486415"><span id="translatedtitle">The propagation characteristics of electromagnetic waves through plasma in the near-<span class="hlt">field</span> <span class="hlt">region</span> of low-frequency loop antenna</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, DongLin Li, XiaoPing; Xie, Kai; Liu, ZhiWei</p> <p>2015-10-15</p> <p>A high-speed vehicle flying through the atmosphere between 100 and 20 km may suffer from a “communication blackout.” In this paper, a low frequency system with an on-board loop antenna to receive signals is presented as a potential blackout mitigation method. Because the plasma sheath is in the near-<span class="hlt">field</span> <span class="hlt">region</span> of the loop antenna, the traditional scattering matrix method that is developed for the far-<span class="hlt">field</span> <span class="hlt">region</span> may overestimate the electromagnetic (EM) wave's attenuation. To estimate the EM wave's attenuation in the near-<span class="hlt">field</span> <span class="hlt">region</span>, EM interference (EMI) shielding theory is introduced. Experiments are conducted, and the results verify the EMI shielding theory's effectiveness. Simulations are also conducted with different plasma parameters, and the results obtained show that the EM wave's attenuation in the near-<span class="hlt">field</span> <span class="hlt">region</span> is far below than that in the far-<span class="hlt">field</span> <span class="hlt">region</span>. The EM wave's attenuation increases with the increase in electron density and decreases with the increase in collision frequency. The higher the frequency, the larger is the EM wave's attenuation. During the entire re-entry phase of a RAM-C module, the EM wave's attenuations are below 10 dB for EM waves with a frequency of 1 MHz and below 1 dB for EM waves with a frequency of 100 kHz. Therefore, the low frequency systems (e.g., Loran-C) may provide a way to transmit some key information to high-speed vehicles even during the communication “blackout” period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhPl...22j2106L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhPl...22j2106L"><span id="translatedtitle">The propagation characteristics of electromagnetic waves through plasma in the near-<span class="hlt">field</span> <span class="hlt">region</span> of low-frequency loop antenna</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, DongLin; Li, XiaoPing; Xie, Kai; Liu, ZhiWei</p> <p>2015-10-01</p> <p>A high-speed vehicle flying through the atmosphere between 100 and 20 km may suffer from a "communication blackout." In this paper, a low frequency system with an on-board loop antenna to receive signals is presented as a potential blackout mitigation method. Because the plasma sheath is in the near-<span class="hlt">field</span> <span class="hlt">region</span> of the loop antenna, the traditional scattering matrix method that is developed for the far-<span class="hlt">field</span> <span class="hlt">region</span> may overestimate the electromagnetic (EM) wave's attenuation. To estimate the EM wave's attenuation in the near-<span class="hlt">field</span> <span class="hlt">region</span>, EM interference (EMI) shielding theory is introduced. Experiments are conducted, and the results verify the EMI shielding theory's effectiveness. Simulations are also conducted with different plasma parameters, and the results obtained show that the EM wave's attenuation in the near-<span class="hlt">field</span> <span class="hlt">region</span> is far below than that in the far-<span class="hlt">field</span> <span class="hlt">region</span>. The EM wave's attenuation increases with the increase in electron density and decreases with the increase in collision frequency. The higher the frequency, the larger is the EM wave's attenuation. During the entire re-entry phase of a RAM-C module, the EM wave's attenuations are below 10 dB for EM waves with a frequency of 1 MHz and below 1 dB for EM waves with a frequency of 100 kHz. Therefore, the low frequency systems (e.g., Loran-C) may provide a way to transmit some key information to high-speed vehicles even during the communication "blackout" period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.5010T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.5010T"><span id="translatedtitle"><span class="hlt">Regional</span> geomagnetic main <span class="hlt">field</span> and secular variation modelling using ground, satellite and marine cross-over data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Talarn, Àngela; Pavón-Carrasco, F. Javier; Miquel Torta, J.; Qamili, Enkelejda</p> <p>2014-05-01</p> <p>After the good results obtained from an attempt to generate a <span class="hlt">regional</span> model for the secular variation of the total geomagnetic <span class="hlt">field</span> for gaining a better knowledge of the <span class="hlt">field</span> over oceanic <span class="hlt">regions</span>, we now present a new <span class="hlt">regional</span> model for the full vector main <span class="hlt">field</span> and its secular variation from 1960.0 to 2000.0 over the North Atlantic Ocean. The distinct facts of our approach with respect to previous existing global models arise from the new information afforded by a collection and selection of marine cross-over data, along with the techniques that we propose for constructing the <span class="hlt">regional</span> model, which include uncertainty estimates of the results. The marine data offer the possibility to gain better and robust knowledge of the <span class="hlt">field</span> over large areas lacked of observatories over periods of time without satellite information. In addition to the marine data, we used observatory and repeat station data in the peripheral areas and satellite data from OERSTED, MAGSAT and the OGO series. All the data passed a rigorous selection in order to reject suspicious data and different random selections of satellite data were applied to reduce the effect of the satellite tracks. Due to the use of different altitude data, we obtained our model using the Revised Spherical Cap Harmonic Analysis (R-SCHA) in space and the penalized cubic B-splines in time. Taking advantage of the orthogonality of the basis functions, being particularly important in the inverse problem approach, we introduced two temporal and spatial regularization matrices with appropriate damping parameters, which are adjusted to assess the best compromise between the data fit and the model roughness. The obtained results show an improvement in terms of root mean square error when the <span class="hlt">regional</span> model is compared with other global models for those epochs, such as the CM4, highlighting the importance of the use of the cross-over marine data in the oceanic <span class="hlt">regions</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19810053721&hterms=solar+wind+magnetic+field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Bwind%2Bmagnetic%2Bfield','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19810053721&hterms=solar+wind+magnetic+field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Bwind%2Bmagnetic%2Bfield"><span id="translatedtitle">Solar flare acceleration of solar wind - Influence of active <span class="hlt">region</span> magnetic <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lundstedt, H.; Wilcox, J. M.; Scherrer, P. H.</p> <p>1981-01-01</p> <p>The direction of the photospheric magnetic <span class="hlt">field</span> at the site of a solar flare is a good predictor of whether the flare will accelerate solar wind plasma. If the <span class="hlt">field</span> has a southward component, high-speed solar wind plasma is usually observed near the earth about 4 days later. If the <span class="hlt">field</span> has a northward component, such high-speed solar wind is almost never observed. Southward-<span class="hlt">field</span> flares may then be expected to have much larger terrestrial effects than northward flares.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-01-31/pdf/2012-2044.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-01-31/pdf/2012-2044.pdf"><span id="translatedtitle">77 FR 4862 - Agency Requests for Renewal of a Previously Approved Information Collection: SBTRC <span class="hlt">Regional</span> <span class="hlt">Field</span>...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-01-31</p> <p>... completed during the quarter. The Quarterly Report Form provides a more composite and comprehensive review... <span class="hlt">Field</span> Offices include business analysis, general management & technical assistance and...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JGRB..107.2131R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JGRB..107.2131R"><span id="translatedtitle">Tectonic forces controlling the <span class="hlt">regional</span> intraplate stress <span class="hlt">field</span> in continental Australia: Results from new finite element modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reynolds, Scott D.; Coblentz, David D.; Hillis, Richard R.</p> <p>2002-07-01</p> <p>The tectonic forces controlling the present-day <span class="hlt">regional</span> intraplate stress <span class="hlt">field</span> in continental Australia have been evaluated through a finite element analysis of the intraplate stresses in the Indo-Australian plate (IAP). Constraint for the modeling is provided by an observed <span class="hlt">regional</span> stress <span class="hlt">field</span> based on observations in 12 stress provinces. A weighted ``basis set'' method has been employed to provide an efficient means to evaluate a very large number of tectonic force combinations and to make a quantitative assessment of the fit between the observed and predicted stress <span class="hlt">fields</span>. Our modeling results indicate that the major features of the <span class="hlt">regional</span> stress <span class="hlt">field</span> in continental Australia can be explained in terms of a geologically plausible array of tectonic forces. While the results continue to substantiate that modeling of the Australian intraplate stress <span class="hlt">field</span> is inherently nonunique, we are nevertheless able to draw a number of fundamental conclusions about the tectonic settings along the principal plate boundary segments including the following: (1) The Himalayan and New Guinea boundaries exert a compressional force on the IAP. (2) Fitting the stress <span class="hlt">field</span> in the Bowen Basin requires compressional boundary forces along the Solomon and New Hebrides subduction zones directed toward the interior of the IAP. (3) East-west compression in eastern Australia requires a small compressional force along the Tonga-Kermadec subduction zone. (4) Fitting the stress <span class="hlt">field</span> in southeastern Australia requires compressional forces along the New Zealand, Puysegur Trench, and Macquarie Ridge boundary segments. (5) Significant tensional slab-pull forces exist only along the Java subduction zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840065173&hterms=paris+region&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dparis%2Bregion','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840065173&hterms=paris+region&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dparis%2Bregion"><span id="translatedtitle">Coronal extension of flaring <span class="hlt">region</span> magnetic <span class="hlt">fields</span> inferred from high-resolution microwave and type III burst observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lantos, P.; Pick, M.; Kundu, M. R.</p> <p>1984-01-01</p> <p>Observations of three solar radio bursts, obtained with the Very Large Array of the National Radio Astronomy Observatory at 6 cm wavelength, have been combined with meter observations from the Mark III Nancay Radioheliograph. There is a good correlation between solar activity observed at the two wavelength domains. A small change by about 10 sec in the centimetric burst location corresponds to a large change, by about 0.5 solar radius, in the related metric type III burst location. This indicates discrete injection/acceleration <span class="hlt">regions</span> and the presence of very divergent magnetic <span class="hlt">fields</span>. The bursts come from two distinct active <span class="hlt">regions</span>. With two-dimensional spatial resolution, it is shown that, in this sample, each active <span class="hlt">region</span> possesses a coronal extension that is separated from that of the neighboring active <span class="hlt">region</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23000477','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23000477"><span id="translatedtitle">A neural network based ensemble approach for improving the accuracy of meteorological <span class="hlt">fields</span> used for <span class="hlt">regional</span> air quality modeling.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Shuiyuan; Li, Li; Chen, Dongsheng; Li, Jianbing</p> <p>2012-12-15</p> <p>A neural network based ensemble methodology was presented in this study to improve the accuracy of meteorological input <span class="hlt">fields</span> for <span class="hlt">regional</span> air quality modeling. Through nonlinear integration of simulation results from two meteorological models (MM5 and WRF), the ensemble approach focused on the optimization of meteorological variable values (temperature, surface air pressure, and wind <span class="hlt">field</span>) in the vertical layer near ground. To illustrate the proposed approach, a case study in northern China during two selected air pollution events, in 2006, was conducted. The performances of the MM5, the WRF, and the ensemble approach were assessed using different statistical measures. The results indicated that the ensemble approach had a higher simulation accuracy than the MM5 and the WRF model. Performance was improved by more than 12.9% for temperature, 18.7% for surface air pressure <span class="hlt">field</span>, and 17.7% for wind <span class="hlt">field</span>. The atmospheric PM(10) concentrations in the study <span class="hlt">region</span> were also simulated by coupling the air quality model CMAQ with the MM5 model, the WRF model, and the ensemble model. It was found that the modeling accuracy of the ensemble-CMAQ model was improved by more than 7.0% and 17.8% when compared to the MM5-CMAQ and the WRF-CMAQ models, respectively. The proposed neural network based meteorological modeling approach holds great potential for improving the performance of <span class="hlt">regional</span> air quality modeling. PMID:23000477</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021436&hterms=cirs&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcirs','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021436&hterms=cirs&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcirs"><span id="translatedtitle">Energization in <span class="hlt">regions</span> of CIRs unconnected to shocks are probably not the result of cross-<span class="hlt">field</span> transport</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Intriligator, Devrie S.; Siscoe, George</p> <p>1995-01-01</p> <p>Corotating energetic ion populations (CEIPs) associated with the forward and reverse shocks of corotating interaction <span class="hlt">regions</span> (CIRs) are observed in CIRs at places where models say are magnetically unconnected to either shock. Such disconnections between CEIPs and shocks are common and have been documented with data from Pioneers 10 and 11 and confirmed with data from Ulysses. They pose a problem for models that account for these CEIPs in terms of ion energization at the shocks followed by ion propagation along <span class="hlt">field</span> lines. Two possible resolutions to this problem have been suggested: diffusion of the ions across <span class="hlt">field</span> lines and extension of the ion energization process to <span class="hlt">regions</span> beyond the shock waves. Here we quantitatively examine the first of these possibilities. We give the Green's function solution to the convection-diffusion equation applied to idealized CIR geometry, with a source at the reverse shock -- the main producer of CEIPs. Two kinds of diffusion are considered: resonant diffusion and stochastic <span class="hlt">field</span> line diffusion. We find that for resonant diffusion the computed ratio is many orders of magnitudes below the observed ratio. For stochastic <span class="hlt">field</span> line diffusion, the computed ratio approximately equals the observed ratio if a diffusion coefficient appropriate to the free solar wind is used. It is several orders of magnitude below the observed ratio, however, if a diffusion coefficient appropriate to CIRs is used. We conclude that cross-<span class="hlt">field</span> diffusion probably does not account for the presence of energetic ions in <span class="hlt">regions</span> of CIRs that are magnetically unconnected to its shock waves. We suggest that the alternative possibility -- the energetic ions in <span class="hlt">regions</span> magnetically unconnected to shocks result from an acceleration process that is independent of shocks -- be pursued to the point where quantitative tests can be performed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/229657','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/229657"><span id="translatedtitle">Pacific <span class="hlt">region</span> adds <span class="hlt">fields</span> and technology to stretch and amplify huge oil reserves</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lyle, D.</p> <p>1995-12-01</p> <p>The Pacific <span class="hlt">region</span> combines the best features of the oilpatch with three states that give operators plenty of exploration prospects and two states at the forefront of development technology. The <span class="hlt">region</span> offers something for everyone, but it has been hamstrung by low oil prices. It looks as if the repeal on the ban on exports Alaskan oil will go a long way toward easing the low-price restriction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19870052706&hterms=Hale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DHale','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19870052706&hterms=Hale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DHale"><span id="translatedtitle">Flare activity, sunspot motions, and the evolution of vector magnetic <span class="hlt">fields</span> in Hale <span class="hlt">region</span> 17244</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Neidig, Donald F.; Hagyard, Mona J.; Machado, Marcos E.; Smith, Jesse B., Jr.</p> <p>1986-01-01</p> <p>The magnetic and dynamical circumstances leading to the 1B/M4 flare of November 5, 1980 are studied, and a strong association is found between the buildup of magnetic shear and the onset of flare activity within the active <span class="hlt">region</span>. The development of shear, as observed directly in vector magnetograms, is consistent in detail with the dynamical history of the active <span class="hlt">region</span> and identifies the precise location of the optical and hard-X-ray kernels of the flare emission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999RaSc...34..983W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999RaSc...34..983W"><span id="translatedtitle">Low-latitude <span class="hlt">field</span>-aligned irregularities observed in the E <span class="hlt">region</span> with the Piura VHF radar: First results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Woodman, Ronald F.; Chau, Jorge L.; Aquino, Fredy; Rodriguez, Rodolfo R.; Flores, Luis A.</p> <p>1999-07-01</p> <p>We have used the Piura VHF radar (5°12'S, 80°38'W, ˜7.5°N geomagnetic latitude, just outside the magnetic equator) in northern Peru to gather echoes from 3-m E <span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities. We present statistical results of these echoes: percentage of occurrence and histograms of radial velocities and spectral widths, obtained with a 15-day data set gathered in 1996. These E <span class="hlt">region</span> echoes are confined to 95- to 120-km altitude and present spectral characteristics similar to equatorial electrojet (EEJ) echoes generated by a gradient drift instability, i.e., type 2. However, they appear mainly at nighttime and early morning (1800-0800 LT) and therefore do not present a temporal similarity to EEJ echoes. Moreover, we observe the existence of two well-defined types of echoes: (1) lower E <span class="hlt">region</span> echoes (95-105 km) and upper E <span class="hlt">region</span> echoes (105-120 km). Both <span class="hlt">regions</span> show different spectral and temporal characteristics. It is difficult to determine at this point the physical mechanisms responsible for the formation of the irregularities without measurements of E <span class="hlt">fields</span> and density gradients, which we plan to do in a future experiment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=240180','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=240180"><span id="translatedtitle">Overview of BEAREX08, A remote sensing <span class="hlt">field</span> experiment on ET at <span class="hlt">field</span>, multi-<span class="hlt">field</span> and <span class="hlt">regional</span> scales using measurements and models</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>In 2008, scientists from eight federal and state institutions worked together to investigate temporal and spatial variations of the surface energy balance and evapotranspiration (ET) in a semi-arid irrigated and dryland agricultural <span class="hlt">region</span> in the Texas Panhandle. Micrometeorological fluxes (surface ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMSM11C..02L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMSM11C..02L"><span id="translatedtitle">Transverse ion heating, <span class="hlt">field</span>-aligned electron acceleration, and parallel electric <span class="hlt">fields</span> in the auroral acceleration <span class="hlt">region</span>: Modeling several FAST events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lund, E. J.; Nguyen, T. T.; Jasperse, J. R.; Basu, B.</p> <p>2008-12-01</p> <p>Many of the ions in the magnetosphere originate in the ionosphere, whence they are extracted by wave heating perpendicular to the magnetic <span class="hlt">field</span>. Much of this ion heating occurs in <span class="hlt">regions</span> where electrons are also accelerated along the magnetic <span class="hlt">field</span>, and the differing anisotropies lead to a charge separation which is balanced by a parallel electric <span class="hlt">field</span>.a Using a recently developed model which includes turbulent heating,b,c we investigate the distribution of parallel electric <span class="hlt">fields</span> in several events measured with the FAST satellite. We investigate the effects of different model closures on the predicted parallel electric <span class="hlt">fields</span>. The goal of the research is to develop a physics-based module of ion outflow to include in global models of the magnetosphere. a Alfvén, H., and C.-G. Fälthammar (1963), Cosmical Electrodynamics: Fundamental Principles, Clarendon Press, Oxford. b Jasperse, J. R., et al. (2006), Phys. Plasmas 13, 072903. c Jasperse, J. R., et al. (2006), Phys. Plasmas 13, 112902.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...821...92C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...821...92C"><span id="translatedtitle">Denser Sampling of the Rosette Nebula with Faraday Rotation Measurements: Improved Estimates of Magnetic <span class="hlt">Fields</span> in H II <span class="hlt">Regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Costa, Allison H.; Spangler, Steven R.; Sink, Joseph R.; Brown, Shea; Mao, Sui Ann</p> <p>2016-04-01</p> <p>We report Faraday rotation measurements of 11 extragalactic radio sources with lines of sight through the Rosette Nebula, a prominent H ii <span class="hlt">region</span> associated with the star cluster NGC 2244. The goal of these measurements is to better determine the strength and structure of the magnetic <span class="hlt">field</span> in the nebula. We calculate the rotation measure (RM) through two methods, a least-squares fit to χ ({λ }2) and Rotation Measure Synthesis. In conjunction with our results from Savage et al., we find an excess RM due to the shell of the nebula of +40 to +1200 rad m-2 above a background RM of +147 rad m-2. We discuss two forms of a simple shell model intended to reproduce the magnitude of the observed RM as a function of distance from the center of the Rosette Nebula. The models represent different physical situations for the magnetic <span class="hlt">field</span> within the shell of the nebula. The first assumes that there is an increase in the magnetic <span class="hlt">field</span> strength and plasma density at the outer radius of the H ii <span class="hlt">region</span>, such as would be produced by a strong magnetohydrodynamic shock wave. The second model assumes that any increase in the RM is due solely to an increase in the density, and the Galactic magnetic <span class="hlt">field</span> is unaffected in the shell. We employ a Bayesian analysis to compare the two forms of the model. The results of this analysis were inconclusive, although the model without amplification of the interstellar magnetic <span class="hlt">field</span> is weakly favored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22348458','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22348458"><span id="translatedtitle">Effects of external radiation <span class="hlt">fields</span> on line emission—application to star-forming <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chatzikos, Marios; Ferland, G. J.; Williams, R. J. R.; Porter, Ryan; Van Hoof, P. A. M.</p> <p>2013-12-20</p> <p>A variety of astronomical environments contain clouds irradiated by a combination of isotropic and beamed radiation <span class="hlt">fields</span>. For example, molecular clouds may be irradiated by the isotropic cosmic microwave background, as well as by a nearby active galactic nucleus. These radiation <span class="hlt">fields</span> excite atoms and molecules and produce emission in different ways. We revisit the escape probability theorem and derive a novel expression that accounts for the presence of external radiation <span class="hlt">fields</span>. We show that when the <span class="hlt">field</span> is isotropic the escape probability is reduced relative to that in the absence of external radiation. This is in agreement with previous results obtained under ad hoc assumptions or with the two-level system, but can be applied to complex many-level models of atoms or molecules. This treatment is in the development version of the spectral synthesis code CLOUDY. We examine the spectrum of a Spitzer cloud embedded in the local interstellar radiation <span class="hlt">field</span> and show that about 60% of its emission lines are sensitive to background subtraction. We argue that this geometric approach could provide an additional tool toward understanding the complex radiation <span class="hlt">fields</span> of starburst galaxies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24514306','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24514306"><span id="translatedtitle">Measurement of absolute <span class="hlt">regional</span> lung air volumes from near-<span class="hlt">field</span> x-ray speckles.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Leong, Andrew F T; Paganin, David M; Hooper, Stuart B; Siew, Melissa L; Kitchen, Marcus J</p> <p>2013-11-18</p> <p>Propagation-based phase contrast x-ray (PBX) imaging yields high contrast images of the lung where airways that overlap in projection coherently scatter the x-rays, giving rise to a speckled intensity due to interference effects. Our previous works have shown that total and <span class="hlt">regional</span> changes in lung air volumes can be accurately measured from two-dimensional (2D) absorption or phase contrast images when the subject is immersed in a water-filled container. In this paper we demonstrate how the phase contrast speckle patterns can be used to directly measure absolute <span class="hlt">regional</span> lung air volumes from 2D PBX images without the need for a water-filled container. We justify this technique analytically and via simulation using the transport-of-intensity equation and calibrate the technique using our existing methods for measuring lung air volume. Finally, we show the full capabilities of this technique for measuring <span class="hlt">regional</span> differences in lung aeration. PMID:24514306</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810458G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810458G"><span id="translatedtitle">The role of waves and DC electric <span class="hlt">fields</span> for electron heating and acceleration in the diffusion <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Graham, Daniel; Khotyaintsev, Yuri; Vaivads, Andris; Norgren, Cecilia; Andre, Mats; Lindqvist, Per-Arne; Le Contel, Olivier; Ergun, Robert; Goodrich, Katherine; Torbert, Roy; Burch, James; Russell, Christopher; Magnes, Werner; Giles, Barbara; Pollock, Craig; Mauk, Barry; Fuselier, Stephen</p> <p>2016-04-01</p> <p>Magnetic reconnection is a fundamental process in solar and astrophysical plasmas. The processes operating at electron spatial-scales, which enable magnetic <span class="hlt">field</span> lines to reconnect, are generally difficult to resolve and identify. However, the recently launched Magnetospheric Multiscale (MMS) mission is specifically designed to resolve electron spatial scales. We use the MMS spacecraft to investigate the process operating within the diffusion <span class="hlt">region</span> to determine the causes of electron heating and acceleration. In particular, we investigate the type of electrostatic and electromagnetic waves that develop and how they affect the electron distributions. We also compare the roles of wave-particle interactions with DC electric <span class="hlt">fields</span> to determine which is responsible for the electron heating observed in diffusion <span class="hlt">regions</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19830030751&hterms=1061&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2526%25231061','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19830030751&hterms=1061&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2526%25231061"><span id="translatedtitle">Dawn-dusk asymmetry of the tail <span class="hlt">region</span> of the magnetosphere of Saturn and the interplanetary magnetic <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Akasofu, S.-I.; Roederer, M.; Krimigis, S. M.</p> <p>1982-01-01</p> <p>In connection with the findings of the Voyager 1 mission, it appears that the tail lobe of Saturn is very different from that of earth and Jupiter, in that the latter are devoid of energetic particles, and magnetic <span class="hlt">field</span> lines in this <span class="hlt">region</span> are thought to be open and interconnecting with the interplanetary magnetic <span class="hlt">field</span> at large distances in the antisolar direction. The present investigation is concerned with a possible explanation of these observations, taking into account a model of Saturn's magnetosphere. It is shown that the Voyager 1 spacecraft remained in the closed <span class="hlt">region</span> of the magnetotail during its entire tail traversal and did not have an opportunity to penetrate into the high latitude lobe. It is concluded that Saturn probably has a tail lobe just like earth and Jupiter. However, this tail lobe was not traversed by Voyager.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/573872','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/573872"><span id="translatedtitle">Concerning effects of low-beta <span class="hlt">region</span> fringe <span class="hlt">fields</span> and multipole error distribution on dynamics in LHC.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meot, F.; Paris, A.</p> <p>1997-08-01</p> <p>Effects of fringe <span class="hlt">fields</span> in separation dipoles D1/D2 and low-{beta} quadrupoles Q1-Q3 of LHC interaction <span class="hlt">regions</span> in collision optics are investigated by means of stepwise ray-tracing in terms of aberrations, beam envelopes and other detunings. Effects of the longitudinal distribution of b{sub 10} error coefficient are next investigated in a similar way for assessment and comparison.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNH53A1718E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNH53A1718E"><span id="translatedtitle">Multiple mapping techniques of glaciovolcanic <span class="hlt">regions</span>: Remote sensing and <span class="hlt">field</span> mapping of Askja (Dyngjufjöll), Iceland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ellis, M. K.; Graettinger, A. H.; Reath, K. A.; Skilling, I. P.; Ramsey, M. S.; Hughes, C. G.</p> <p>2011-12-01</p> <p>The Icelandic landscape is dominated by basaltic glaciovolcanic and Holocene post-glacial landforms. The lack of chemical diversity has led to significant simplification of <span class="hlt">regional</span> maps. This includes areas of historic volcanic activity, such as Askja (Dyngjufjöll) in central Iceland. The purpose of this study is to improve the resolution of the <span class="hlt">regional</span> map through the identification of variations within glaciovolcanic units and to more accurately constrain the products of historic eruptions. As part of a greater project to map the 45 km2 glaciovolcanic deposits of Askja volcano, Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) based mapping of the <span class="hlt">region</span> surrounding the Dyngjufjöll massif was undertaken using previous datasets and recent <span class="hlt">field</span> work for validation. Maps were based on 3 ASTER scenes obtained during overpasses in August 2010 and 2011. <span class="hlt">Field</span> mapping conducted in August 2010 and 2011 of the glaciovolcanic deposits, previous geologic maps of the Holocene deposits (Annertz 1985, Sigvaldason 1992) and previous remote sensing based investigations (Hjartardottir et al. 2009) were utilized to validate Visible/Near-Infrared (VNIR) and Thermal Infrared (TIR) based maps. Laboratory based TIR data were collected from samples of representative lithologic units within the <span class="hlt">field</span> area, including glaciovolcanic deposits (pillow lavas, hyaloclastite, etc.), historical deposits (1875 pumice, 1960's basaltic lavas), and Holocene basaltic lavas from Askja. This project produced a highly detailed map of the distribution of the remaining eroded 1875 deposit within the proximal (<50 km) vent area as well as, the complexity of neighboring glaciovolcanic massifs. Additionally, the products of this investigation demonstrate the potential for remote sensing based mapping of glaciovolcanic deposits throughout Iceland and other well exposed geologic <span class="hlt">regions</span> (i.e. British Columbia). Remote sensing aided mapping will benefit glaciovolcanic studies by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21192032','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21192032"><span id="translatedtitle">Hyperdeformation in the cranked relativistic mean <span class="hlt">field</span> theory: The Z=40-58 <span class="hlt">region</span> of the nuclear chart</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Afanasjev, A. V.; Abusara, H.</p> <p>2008-07-15</p> <p>The systematic investigation of hyperdeformation (HD) at high spin in the Z=40-58 <span class="hlt">region</span> of the nuclear chart was performed in the framework of the cranked relativistic mean-<span class="hlt">field</span> theory. The properties of the moments of inertia of the HD bands, the role of the single-particle and necking degrees of freedom at HD, the spins at which the HD bands become yrast, the possibility to observe discrete HD bands, and so on are discussed in detail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016E%26ES...33a2020N&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016E%26ES...33a2020N&link_type=ABSTRACT"><span id="translatedtitle">Groundwater microflora of the Aptian-Cenomanian deposits at the Igolsko-Talovoe <span class="hlt">field</span> in Tomsk <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nalivaiko, N. G.; Dutova, E. M.; Spiridonov, T. S.</p> <p>2016-03-01</p> <p>The authors have studied the microbiological composition of the groundwater of the Aptian-Cenomanian deposits in the territory of the Igolsko-Talovoe <span class="hlt">field</span> in Tomsk <span class="hlt">Region</span>. The detected diversity of the physiological groups of bacteria can be a corrosive component for waters used in the reservoir pressure maintenance system. The research findings have allowed making conclusions about the need to study the contribution of all microorganisms inhabiting the waters of the Aptian-Cenomanian deposits to corrosion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016cosp...41E1773S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016cosp...41E1773S&link_type=ABSTRACT"><span id="translatedtitle">Radar observations of F <span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities over Hainan island, China in 2014-2015</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shang, She-Ping; Wu, Qiongzhi; Chunxiao, Yan; Yan, Jingye; Shi, Jiankui; Yang, Guotao</p> <p>2016-07-01</p> <p>The morphology characteristics of low latitude F <span class="hlt">region</span> 3-m scale <span class="hlt">field</span>-aligned irregularities (FAIs) have been investigated by using the continuous observation of Hainan VHF radar (19.5ºN,109.1ºE,dip latitude:14.0ºN) in 2014-2015. The monthly mean F10.7 solar flux show the clear decrease from the peak in the start of 2014 to the foot in the end of 2015. F <span class="hlt">region</span> FAIs can be further classified into the three cases: radar plumes (RP), broad spread F (BSF) and weak spread F (WSF), in which the first are mainly generated and developed within the <span class="hlt">field</span> of view (FoV) of radar and the latter two generally originate outside of the FoV of radar and drift into the FoV of radar. They indicate the different phases of generation, evolution and decay of low latitude F <span class="hlt">region</span> irregularities. The main results exhibit the F <span class="hlt">region</span> FAIs mainly present in Feb.-Apr. and in Sep.-Nov. near the two equinoxes and are greatly reduced in May-Aug. near summer solstice, and almost completely disappeared in Dec.-Jan. near winter solstice, which are greatly affected by the solar activity. F <span class="hlt">region</span> FAIs are more robust in spring equinox than in fall equinox, which can be shown as the occurrence rate, the structure and evolution, the duration time and so on. In spring equinox, the occurrence rate is far higher, and F <span class="hlt">region</span> FAIs show the more structures and the longer duration time. RP near sunset are greatly enhanced. The following BSF and WSF can present intermittently and may persist into the post-midnight. F <span class="hlt">region</span> FAIs in summer solstice mainly show BSF and WSF with the clear time delay. BSF mainly present in the pre-midnight, and there are mostly WSF in the post-midnight. The clear decrease of sola flux cause different effects to the occurrence of F <span class="hlt">region</span> FAIs in the equinoxes and summer solstice. F <span class="hlt">region</span> FAIs are greatly reduced in the equinoxes, in which RP are greatly reduced compared with BSF and WSF. F <span class="hlt">region</span> FAIs seem not to be evidently affected in the summer solstice, in which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApGeo..13...59F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApGeo..13...59F"><span id="translatedtitle"><span class="hlt">Regional</span> magnetic anomaly <span class="hlt">fields</span>: 3D Taylor polynomial and surface spline models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Yan; Jiang, Yong; Jiang, Yi; Li, Zheng; Jiang, Jin; Liu, Zhong-Wei; Ye, Mei-Chen; Wang, Hong-Sheng; Li, Xiu-Ming</p> <p>2016-03-01</p> <p>We used data from 1960.0, 1970.0, 1980.0, 1990.0, and 2000.0 to study the geomagnetic anomaly <span class="hlt">field</span> over the Chinese mainland by using the three-dimensional Taylor polynomial (3DTP) and the surface spline (SS) models. To obtain the pure anomaly <span class="hlt">field</span>, the main <span class="hlt">field</span> and the induced <span class="hlt">field</span> of the ionospheric and magnetospheric <span class="hlt">fields</span> were removed from measured data. We also compared the SS model anomalies and the data obtained with Kriging interpolation (KI). The geomagnetic anomaly distribution over the mainland was analyzed based on the SS and 3DTP models by transferring all points from 1960.0-1990.0 to 2000.0. The results suggest that the total intensity F anomalies estimated based on the SS and KI for each year are basically consistent in distribution and intensity. The anomalous distributions in the X-, Y-, and Z-direction and F are mainly negative. The 3DTP model anomalies suggest that the intensity in the X-direction increases from -100 nT to 0 nT with longitude, whereas the intensity in the Y-direction decreases from 400 nT to 20 nT with longitude and over the eastern mainland is almost negative. The intensity in the Z-direction and F are very similar and in most areas it is about -50nT and higher in western Tibet. The SS model anomalies overall reflect the actual distribution of the magnetic <span class="hlt">field</span> anomalies; however, because of the uneven distribution of measurements, it yields several big anomalies. Owing to the added altitude term, the 3DTP model offers higher precision and is consistent with KI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11935226','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11935226"><span id="translatedtitle">Visual <span class="hlt">field</span> structure in the Empress Leilia, Asterocampa leilia (Lepidoptera, Nymphalidae): dimensions and <span class="hlt">regional</span> variation in acuity.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rutowski, Ronald L; Warrant, Eric J</p> <p>2002-02-01</p> <p>Male Empress Leilia butterflies ( Asterocampa leilia) use a sit-and-wait tactic to locate mates. To see how vision might influence male behavior, we studied the morphology, optics, and receptor physiology of their eyes and found the following. (1) Each eye's visual <span class="hlt">field</span> is approximately hemispherical with at most a 10 degrees overlap in the <span class="hlt">fields</span> of the eyes. There are no large sexual differences in visual <span class="hlt">field</span> dimensions. (2) In both sexes, rhabdoms in the frontal and dorsal ommatidia are longer than those in other eye <span class="hlt">regions</span>. (3) Interommatidial angles are smallest frontally and around the equator of the eye. Minimum interommatidial angles are 0.9-1 degrees in males and 1.3-1.4 degrees in females. (4) Acceptance angles of ommatidia closely match interommatidial angles in the frontal <span class="hlt">region</span> of the eye. We conclude that vision in these butterflies is mostly monocular and that males have more acute vision than females, especially in the frontal <span class="hlt">region</span> (large facets, small interommatidial angles, small acceptance angles, long rhabdoms, and a close match between interommatidial angles and acceptance angles). This study also suggests that perched males direct their most acute vision where females are likely to appear but show no eye modifications that appear clearly related to a mate-locating tactic. PMID:11935226</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8491O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8491O"><span id="translatedtitle">A simple simulation approach to generate complex rainfall <span class="hlt">fields</span> conditioned by elevation: example of the eastern Mediterranean <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oriani, Fabio; Ohana-Levi, Noa; Straubhaar, Julien; Renard, Philippe; Karnieli, Arnon; Mariethoz, Grégoire; Morin, Efrat; Marra, Francesco</p> <p>2016-04-01</p> <p>Stochastically generating realistic rainfall <span class="hlt">fields</span> is useful to study the uncertainty related to catchment recharge and its propagation to distributed hydrological models. To this end, it is critical to use weather radar images as training data, being the single most informative source for rainfall spatial heterogeneity. Generating realistic simulations is particularly important in <span class="hlt">regions</span> like the eastern Mediterranean, where the synoptic conditions can lead to rainfall <span class="hlt">fields</span> presenting various morphology, anisotropy and non-stationarity. The Direct Sampling (DS) technique [Mariethoz2010] is proposed here as a stochastic generator of spatial daily rainfall <span class="hlt">fields</span> relying on the simulation of radar imagery. The technique is based on resampling of a training data set (in this case, a stack of radar images) and the generation of similar patterns to the ones found in the data. The strong point of DS, which makes it an attractive simulation approach for rainfall, is its capability to preserve the high-order statistical features present in the training image (e.g., rainfall cell shape, spatial non-stationarity) with minimal parameterization. Moreover, factors influencing rainfall, like elevation, can be used as conditioning variables, without the need of a complex statistical dependence model. A DS setup for radar image simulation is presented and tested for the simulation of daily rainfall <span class="hlt">fields</span> using a 10-year radar-image record from the central <span class="hlt">region</span> of Israel. Using a synoptic weather classification to train the model, the algorithm can generate realistic spatial <span class="hlt">fields</span> for different rainfall types, preserving the variability and the covariance structure of the reference reasonably well. Moreover, the simulation is conditioned using the digital elevation model to preserve the complex relation between rainfall intensity and altitude that is characteristic for this <span class="hlt">region</span>. [Mariethoz2010] G. Mariethoz, P. Renard, and J. Straubhaar. The direct sampling method to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18542668','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18542668"><span id="translatedtitle">Resonant phase jump with enhanced electric <span class="hlt">field</span> caused by surface phonon polariton in terahertz <span class="hlt">region</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Okada, Takanori; Nagai, Masaya; Tanaka, Koichiro</p> <p>2008-04-14</p> <p>We investigated surface phonon polariton in cesium iodide with terahertz time-domain attenuated total reflection method in Otto configuration, which gives us both information on amplitude and phase of surface electromagnetic mode directly. Systematic experiments with precise control of the distance between a prism and an active material show that the abrupt change of pi-phase jump appears sensitively under polariton picture satisfied when the local electric <span class="hlt">field</span> at the interface becomes a maximum. This demonstration will open the novel phase-detection terahertz sensor using the active medium causing the strong enhancement of terahertz electric <span class="hlt">field</span>. PMID:18542668</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/838975','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/838975"><span id="translatedtitle">Inhomogeneous superconductor in an a.c. <span class="hlt">field</span>: Application to the pseudogap <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ovchinnikov, Yu.N.; Kresin, V.Z.</p> <p>2002-02-01</p> <p>The behavior of an inhomogeneous superconductor in an external a.c. <span class="hlt">field</span> is studied. General equations describing the a.c. response are formulated. Special attention is paid to the case of a layered conductor containing superconducting ''islands''. A system of this type displays ''pseudogap'' properties. The surface impedance Z is evaluated. It is shown that the ReZ {ne} |ImZ| and their difference {Delta}Z {proportional_to} {omega}{sup -1/2}, {omega} is the frequency of the a.c. <span class="hlt">field</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title5-vol3/pdf/CFR-2013-title5-vol3-part1201-appII.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title5-vol3/pdf/CFR-2013-title5-vol3-part1201-appII.pdf"><span id="translatedtitle">5 CFR Appendix II to Part 1201 - Appropriate <span class="hlt">Regional</span> or <span class="hlt">Field</span> Office for Filing Appeals</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>...; Maryland—except the counties of Montgomery and Prince George's; Massachusetts; New Hampshire; New Jersey... Rico; and Virgin Islands). 4. Washington <span class="hlt">Regional</span> Office, 1800 Diagonal Road, Alexandria, Virginia 22314, Facsimile No.: (703) 756-7112, (Maryland—counties of Montgomery and Prince George's;...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title5-vol3/pdf/CFR-2014-title5-vol3-part1201-appII.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title5-vol3/pdf/CFR-2014-title5-vol3-part1201-appII.pdf"><span id="translatedtitle">5 CFR Appendix II to Part 1201 - Appropriate <span class="hlt">Regional</span> or <span class="hlt">Field</span> Office for Filing Appeals</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>...; Maryland—except the counties of Montgomery and Prince George's; Massachusetts; New Hampshire; New Jersey... Rico; and Virgin Islands). 4. Washington <span class="hlt">Regional</span> Office, 1901 S. Bell Street, Arlington, Virginia 22202, Facsimile No.: (703) 756-7112, (Maryland—counties of Montgomery and Prince George's;...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title5-vol3/pdf/CFR-2010-title5-vol3-part1201-appII.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title5-vol3/pdf/CFR-2010-title5-vol3-part1201-appII.pdf"><span id="translatedtitle">5 CFR Appendix II to Part 1201 - Appropriate <span class="hlt">Regional</span> or <span class="hlt">Field</span> Office for Filing Appeals</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>...; Maryland—except the counties of Montgomery and Prince George's; Massachusetts; New Hampshire; New Jersey... Rico; and Virgin Islands). 4. Washington <span class="hlt">Regional</span> Office, 1800 Diagonal Road, Alexandria, Virginia 22314, Facsimile No.: (703) 756-7112, (Maryland—counties of Montgomery and Prince George's;...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title5-vol3/pdf/CFR-2012-title5-vol3-part1201-appII.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title5-vol3/pdf/CFR-2012-title5-vol3-part1201-appII.pdf"><span id="translatedtitle">5 CFR Appendix II to Part 1201 - Appropriate <span class="hlt">Regional</span> or <span class="hlt">Field</span> Office for Filing Appeals</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>...; Maryland—except the counties of Montgomery and Prince George's; Massachusetts; New Hampshire; New Jersey... Rico; and Virgin Islands). 4. Washington <span class="hlt">Regional</span> Office, 1800 Diagonal Road, Alexandria, Virginia 22314, Facsimile No.: (703) 756-7112, (Maryland—counties of Montgomery and Prince George's;...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-03-22/pdf/2012-6964.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-03-22/pdf/2012-6964.pdf"><span id="translatedtitle">77 FR 16850 - Notice of Reclassification of One Investigative <span class="hlt">Field</span> Office to <span class="hlt">Regional</span> Office: Denver, CO</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-03-22</p> <p>... of investigation as a <span class="hlt">regional</span> office of investigation. SUMMARY: This notice advises the public that... furniture or equipment is involved. (d) Space alteration costs (de minimus). Some offices may require slight space alterations and telephone changes to accommodate assigned staff and the new SAC. However,...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=219619','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=219619"><span id="translatedtitle"><span class="hlt">Field</span> evaluation of anthracnose resistance for sorghum germplasm from the Sikasso <span class="hlt">region</span> in Mali</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>The USDA, ARS National Plant Germplasm System maintains 132 sorghum landraces from the Sikasso <span class="hlt">region</span> of Mali. This germplasm was inoculated with Colletotrichum sublineolum and evaluated for foliar anthracnose resistance at the USDA, ARS Tropical Agriculture Research Station in Isabela, Puerto Rico...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008A%26A...483..609F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008A%26A...483..609F"><span id="translatedtitle">Radiative and magnetic properties of solar active <span class="hlt">regions</span>. I. Global magnetic <span class="hlt">field</span> and EUV line intensities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fludra, A.; Ireland, J.</p> <p>2008-05-01</p> <p>Context: The relationships between the photospheric magnetic flux and either the X-ray or extreme ultraviolet emission from the solar atmosphere have been studied by several authors. Power-law relations have been found between the total magnetic flux and X-ray flux or intensities of the chromospheric, transition <span class="hlt">region</span>, and coronal emission lines in solar active <span class="hlt">regions</span>. These relations were then used to infer the mechanism of the coronal heating. Aims: We derive accurate power laws between EUV line intensities and the total magnetic flux in solar active <span class="hlt">regions</span> and discuss their applications. We examine whether these global power laws are capable of providing the diagnostics of the coronal heating mechanism. Methods: This analysis is based on EUV lines recorded by the Coronal Diagnostic Spectrometer (CDS) on SOHO for 48 solar active <span class="hlt">regions</span>, as they crossed the central meridian in years 1996-1998. Four spectral lines are used: He I 584.3 Å (3×104 K), O V 629.7 Å (2.2×105 K), Mg IX 368.06 Å (9.5×105 K), and Fe XVI 360.76 Å (2.0×106 K). In particular, the Fe XVI 360.76 Å line, seen only in areas of enhanced heating in active <span class="hlt">regions</span> or bright points, has not been used before for this analysis. Results: Empirical power laws are established between the total active <span class="hlt">region</span> intensity in the lines listed above and the total magnetic flux. We demonstrate the usefulness of some spatially integrated EUV line intensities, I_T, as a proxy for the total magnetic flux, Φ, in active <span class="hlt">regions</span>. We point out the approximate, empirical nature of the I_T-Φ relationships and discuss the interpretation of the global power index. Different power index values for transition <span class="hlt">region</span> and coronal lines are explained by their different dependence on pressure under the assumption of hydrostatic loop models. However, the global power laws are dominated by the size of the active <span class="hlt">regions</span>, and we demonstrate for the first time the difficulties in uniquely relating the power index in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22364836','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22364836"><span id="translatedtitle">THE IMPORTANCE OF THE MAGNETIC <span class="hlt">FIELD</span> FROM AN SMA-CSO-COMBINED SAMPLE OF STAR-FORMING <span class="hlt">REGIONS</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Koch, Patrick M.; Tang, Ya-Wen; Ho, Paul T. P.; Chen, Huei-Ru Vivien; Liu, Hau-Yu Baobab; Yen, Hsi-Wei; Lai, Shih-Ping; Zhang, Qizhou; Chen, How-Huan; Ching, Tao-Chung; Girart, Josep M.; Frau, Pau; Li, Hua-Bai; Li, Zhi-Yun; Padovani, Marco; Qiu, Keping; Rao, Ramprasad</p> <p>2014-12-20</p> <p>Submillimeter dust polarization measurements of a sample of 50 star-forming <span class="hlt">regions</span>, observed with the Submillimeter Array (SMA) and the Caltech Submillimeter Observatory (CSO) covering parsec-scale clouds to milliparsec-scale cores, are analyzed in order to quantify the magnetic <span class="hlt">field</span> importance. The magnetic <span class="hlt">field</span> misalignment δ—the local angle between magnetic <span class="hlt">field</span> and dust emission gradient—is found to be a prime observable, revealing distinct distributions for sources where the magnetic <span class="hlt">field</span> is preferentially aligned with or perpendicular to the source minor axis. Source-averaged misalignment angles (|δ|) fall into systematically different ranges, reflecting the different source-magnetic <span class="hlt">field</span> configurations. Possible bimodal (|δ|) distributions are found for the separate SMA and CSO samples. Combining both samples broadens the distribution with a wide maximum peak at small (|δ|) values. Assuming the 50 sources to be representative, the prevailing source-magnetic <span class="hlt">field</span> configuration is one that statistically prefers small magnetic <span class="hlt">field</span> misalignments |δ|. When interpreting |δ| together with a magnetohydrodynamics force equation, as developed in the framework of the polarization-intensity gradient method, a sample-based log-linear scaling fits the magnetic <span class="hlt">field</span> tension-to-gravity force ratio (Σ {sub B}) versus (|δ|) with (Σ {sub B}) = 0.116 · exp (0.047 · (|δ|)) ± 0.20 (mean error), providing a way to estimate the relative importance of the magnetic <span class="hlt">field</span>, only based on measurable <span class="hlt">field</span> misalignments |δ|. The force ratio Σ {sub B} discriminates systems that are collapsible on average ((Σ {sub B}) < 1) from other molecular clouds where the magnetic <span class="hlt">field</span> still provides enough resistance against gravitational collapse ((Σ {sub B}) > 1). The sample-wide trend shows a transition around (|δ|) ≈ 45°. Defining an effective gravitational force ∼1 – (Σ {sub B}), the average magnetic-<span class="hlt">field</span>-reduced star formation efficiency is at least a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12805754','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12805754"><span id="translatedtitle">Using simulation and budget models to scale-up nitrogen leaching from <span class="hlt">field</span> to <span class="hlt">region</span> in Canada.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huffman, E C; Yang, J Y; Gameda, S; De Jong, R</p> <p>2001-12-11</p> <p>Efforts are underway at Agriculture and Agri-Food Canada (AAFC) to develop an integrated, nationally applicable, socioeconomic/biophysical modeling capability in order to predict the environmental impacts of policy and program scenarios. This paper outlines our Decision Support System (DSS), which integrates the IROWCN (Indicator of the Risk of Water Contamination by Nitrogen) index with the agricultural policy model CRAM (Canadian <span class="hlt">Regional</span> Agricultural Model) and presents an outline of our methodology to provide independent assessments of the IROWCN results through the use of nitrogen (N) simulation models in select, data-rich areas. Three <span class="hlt">field</span>-level models--DSSAT, N_ABLE, and EPIC--were evaluated using local measured data. The results show that all three dynamic models can be used to simulate biomass, grain yield, and soil N dynamics at the <span class="hlt">field</span> level; but the accuracy of the models differ, suggesting that models need to be calibrated using local measured data before they are used in Canada. Further simulation of IROWCN in a maize <span class="hlt">field</span> using N_ABLE showed that soil-mineral N levels are highly affected by the amount of fertilizer N applied and the time of year, meaning that fertilizer and manure N applications and weather data are crucial for improving IROWCN. Methods of scaling-up simulated IROWCN from <span class="hlt">field</span>-level to soil-landscape polygons and CRAM <span class="hlt">regions</span> are discussed. PMID:12805754</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005SPIE.5962..841P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005SPIE.5962..841P"><span id="translatedtitle">Evaluation of contrast loss introduced by scattering effects at optical mounts: <span class="hlt">field</span> dependence in the IR <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pizarro, C.; Blanco, P.; Arasa, J.; Cifuentes, A. F.</p> <p>2005-09-01</p> <p>The reduction of contrast due to scattering by optical mounts and buffers was studied, especially for the systems that must work in the infrared <span class="hlt">region</span>. When a particular optical system is optimized [1,2] up a specified <span class="hlt">field</span> value the scattering effects introduced by optical mounts and buffers must be taken into account. The scattering effect plays an important role in the IR <span class="hlt">region</span> where the influence of off-<span class="hlt">field</span> effects is important. The contrast reduction due to scattering effects is not uniform with the object position, in other words the influence of scattering effects has <span class="hlt">field</span> dependence. The scattering model used is based on the classical point of view of the scattering electromagnetic wave and it is adapted for optical evaluation using ray-tracing techniques. In order to test the validity of our scattering model we calculated the distribution of illumination produced for a laser beam in a plane-parallel plate with perfect scattering properties at the back surface. The comparison between the results obtained form our model and the analytical models permit us to extrapolate the use of our model in systems that involve more complex geometry. The model was applied in a four element IR objective with germanium and silicon lenses. In all the situations the contrast as a function of the <span class="hlt">field</span> value was calculated, with and without the scattering effects. By contemplating the contrast loss, a better choice of materials, geometries and buffer positions can be made possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=212720','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=212720"><span id="translatedtitle"><span class="hlt">Region</span> and <span class="hlt">field</span> level distributions of aster yellows phytoplasma in small grains crops</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Aster yellows (AY), a disease of small grain crops caused by aster yellows phytoplasma (AYp), produces disease symptoms similar to barley yellow dwarf (BYD). From 2003 to 2005, small grain production <span class="hlt">fields</span> in Minnesota and North Dakota were surveyed to determine the incidences of AY and BYD. In-fie...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-03-22/pdf/2012-6970.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-03-22/pdf/2012-6970.pdf"><span id="translatedtitle">77 FR 16852 - Notice of Reclassification of Five <span class="hlt">Regional</span> Offices to Investigative <span class="hlt">Field</span> Offices: Seattle, WA...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-03-22</p> <p>... Central Islip, New York, sub-<span class="hlt">field</span> office of investigations. SUMMARY: This notice advises the public that.... (d) Space alteration costs (de minimus). Some offices may require space alterations and telephone changes to accommodate any future changes of assigned staff. However, HUD/OIG estimates that any...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=34652&keyword=friction&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=75512570&CFTOKEN=22931671','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=34652&keyword=friction&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=75512570&CFTOKEN=22931671"><span id="translatedtitle">SENSITIVITY OF <span class="hlt">REGIONAL</span> OXIDANT MODEL PREDICTIONS TO PROGNOSTIC AND DIAGNOSTIC METEOROLOGICAL <span class="hlt">FIELDS</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Objective analysis and diagnostic methods are used to provide hourly meteorological <span class="hlt">fields</span> to many air quality simulation models. he viability of using prognostic predictions from the Mesoscale Model Version 4 together with four-dimensional data assimilation techniques (MM4-FDDA)...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=309869','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=309869"><span id="translatedtitle">Quantifying variability in <span class="hlt">field</span> scale evapotranspiration measurements in an irrigated agricultural <span class="hlt">region</span> under advection</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>This study compares the evapotranspiration (ET) measurements from eddy covariance, lysimetry, and water balance using a network of neutron probe sensors and investigates the role of within-<span class="hlt">field</span> variability in the vegetation density in explaining the differences among the ET estimates from the vario...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014IAUS..300..416G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014IAUS..300..416G"><span id="translatedtitle">Coronal Loop Mapping to Infer the Best Magnetic <span class="hlt">Field</span> Models for Active <span class="hlt">Region</span> Prominences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gary, G. Allen; Hu, Qiang; Lee, Jong Kwan</p> <p>2014-01-01</p> <p>This article comments on the results of a new, rapid, and flexible manual method to map on-disk individual coronal loops of a two-dimensional EUV image into the three-dimensional coronal loops. The method by Gary, Hu, and Lee (2013) employs cubic Bézier splines to map coronal loops using only four free parameters per loop. A set of 2D splines for coronal loops is transformed to the best 3D pseudo-magnetic <span class="hlt">field</span> lines for a particular coronal model. The results restrict the magnetic <span class="hlt">field</span> models derived from extrapolations of magnetograms to those admissible and inadmissible via a fitness parameter. This method uses the minimization of the misalignment angles between the magnetic <span class="hlt">field</span> model and the best set of 3D <span class="hlt">field</span> lines that match a set of closed coronal loops. We comment on the implication of the fitness parameter in connection with the magnetic free energy and comment on extensions of our earlier work by considering the issues of employing open coronal loops or employing partial coronal loop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016GeoRL..43.4665D&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016GeoRL..43.4665D&link_type=ABSTRACT"><span id="translatedtitle">A case study of a density structure over a vertical magnetic <span class="hlt">field</span> <span class="hlt">region</span> in the Martian ionosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duru, F.; Gurnett, D. A.; Diéval, C.; Morgan, D. D.; Pisa, D.; Lundin, R.</p> <p>2016-05-01</p> <p>One of the discoveries made by the radar sounder on the Mars Express spacecraft is the existence of magnetically controlled structures in the ionosphere of Mars, which result in bulges in the ionospheric electron density contours. These bulges lead in turn to oblique echoes, which show up as hyperbola-shaped features in the echograms. A hyperbola-shaped feature observed over an isolated <span class="hlt">region</span> of strong crustal magnetic <span class="hlt">field</span> is associated with a plasma cavity in the upper ionosphere and a corresponding density enhancement in the lower levels of the ionosphere. We suggest that along open magnetic <span class="hlt">field</span> lines, the solar wind electrons are accelerated downward and the ionospheric ions are accelerated upward in a manner similar to the <span class="hlt">field</span> line-driven auroral acceleration at Earth. This heating due to precipitating electrons may cause an increase in the scale height and may drive a loss of ionospheric plasma at high altitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989JGR....94...49R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989JGR....94...49R"><span id="translatedtitle">Correlated plasma wave, magnetic <span class="hlt">field</span>, and energetic ion observations in the ion pickup <span class="hlt">region</span> of Comet Giacobini-Zinner</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, I. G.; Wenzel, K.-P.; Cowley, S. W. H.; Scarf, F. L.; Smith, E. J.; Tsurutani, B. T.; Sanderson, T. R.; Hynds, R. J.</p> <p>1989-01-01</p> <p>Relationships between simultaneous plasma wave, magnetic <span class="hlt">field</span>, and energetic heavy ion data obtained by the International Cometary Explorer (ICE) spacecraft in the large-scale solar wind particle pickup <span class="hlt">region</span> surrounding Comet Giacobini-Zinner are examined. In particular, consideration is given to the conditions under which electrostatic emissions at frequencies of a few kilohertz and electromagnetic waves at a few tens of hertz are observed. It is shown that the data are consistent with the view that the kilohertz electrostatic emissions result from a beam-type instability excited by the pickup photoelectron population when the angle alpha between the magnetic <span class="hlt">field</span> and the plasma velocity vectors is not too large. The data also suggest that the few tens of hertz electromagnetic waves may be excited by a ring-type instability associated with the pickup ion population, which occurs when the magnetic <span class="hlt">field</span> is near to orthogonality with the flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AdSpR..43...96G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AdSpR..43...96G"><span id="translatedtitle">Future possibilities for doppler and magnetic <span class="hlt">field</span> measurements in the extended solar atmosphere: Dissecting the transition <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gary, G. Allen; Davis, John M.; West, Edward A.</p> <p>2009-01-01</p> <p>For the first time, a vacuum ultraviolet (VUV) telescope can be built to rapidly observe the magnetic <span class="hlt">fields</span>, plasma flows, and heating events in the Sun’s atmosphere. These observations can provide key data for space weather models. The vacuum ultraviolet <span class="hlt">region</span> allows remote sensing of the upper levels of the solar atmosphere where the magnetic <span class="hlt">field</span> dominates the physics. A VUV Fabry-Pérot interferometer (FPI) will allow us to observe the magnetic <span class="hlt">field</span>, flows, and heating events in the mid-transition <span class="hlt">region</span> (between the chromosphere and corona). Observations of this <span class="hlt">region</span> are needed to directly probe the magnetic structure and activity at the base of the corona where the magnetic <span class="hlt">field</span> is approximately force-free, i.e., where gas pressures are very small. This is a key element in developing accurate models of the Sun’s dynamics for space weather. The specific <span class="hlt">region</span> of interest is the 100 km thick transition <span class="hlt">region</span>, between the chromosphere and the much hotter corona, which strongly emits at 155 nm from triply ionized carbon (C3+) at 100,000 K. This is best observed by an imaging interferometer that combines the best attributes of a spectrograph and an imager. We present the latest results from the NASA Marshall Space Flight Center (MSFC) FPI. The major elements of the tunable CIV VUV FPI are the 35 mm MgF2 etalon plates with a plate finesse of F>25 at 155 nm, the π-dielectric coatings, a Hansen mechanical mount in a pressurize canister, and the piezoelectric control system. The control system for the etalon is a capacitance-stabilized Hovemere Ltd. standard system. The special Cascade Optical Corporation reflectance coatings are 25 pi-multilayers of high low refractive layers paired in phase. This CIV interferometer, when flown above Earth’s atmosphere, will obtain narrow-passband images, magnetograms, and Dopplergrams of the transition <span class="hlt">region</span> in the CIV 155 nm line at a rapid cadence. We recently measured the MSFC VUV FPI using the University of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15634038','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15634038"><span id="translatedtitle">Globally convergent trust-<span class="hlt">region</span> methods for self-consistent <span class="hlt">field</span> electronic structure calculations.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Francisco, Juliano B; Martínez, José Mario; Martínez, Leandro</p> <p>2004-12-01</p> <p>As far as more complex systems are being accessible for quantum chemical calculations, the reliability of the algorithms used becomes increasingly important. Trust-<span class="hlt">region</span> strategies comprise a large family of optimization algorithms that incorporates both robustness and applicability for a great variety of problems. The objective of this work is to provide a basic algorithm and an adequate theoretical framework for the application of globally convergent trust-<span class="hlt">region</span> methods to electronic structure calculations. Closed shell restricted Hartree-Fock calculations are addressed as finite-dimensional nonlinear programming problems with weighted orthogonality constraints. A Levenberg-Marquardt-like modification of a trust-<span class="hlt">region</span> algorithm for constrained optimization is developed for solving this problem. It is proved that this algorithm is globally convergent. The subproblems that ensure global convergence are easy-to-compute projections and are dependent only on the structure of the constraints, thus being extendable to other problems. Numerical experiments are presented, which confirm the theoretical predictions. The structure of the algorithm is such that accelerations can be easily associated without affecting the convergence properties. PMID:15634038</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1616728O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1616728O"><span id="translatedtitle">Stress <span class="hlt">field</span> variations along the Maghreb <span class="hlt">region</span> derived from inversion of fault plane solutions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ousadou, Farida; Dorbath, Louis; Ayadi, abdelhakim; Dorbath, Catherine; Gharbi, Sofiane</p> <p>2014-05-01</p> <p>The analysis of the stress state along the Maghreb <span class="hlt">region</span> is made on the basis of the inversion of focal solutions. We have inverted the main shock and aftershock focal mechanisms of the strongest seismic events that occurred in five seismogenic zones from west to east : Al Hoceima (2004), Cheliff (1980), Tipasa-Chenoua (1989), Zemmouri (2003) and Constantine (1985). Most of the focal mechanisms of the aftershock sequences have been constructed within this study. Compressive stress regime is observed in the central part of Algeria between Cheliff and Zemmouri. On both edges of the Maghreb <span class="hlt">region</span>, the stress regime becomes strike-slip in Constantine <span class="hlt">region</span> and in the Moroccan Rif. These different regimes seem to be linked to the free-edge effect (Ionian slab subduction) and to the dynamics of the Alboran Sea in the eastern and western part of the study area respectively. The sigma1 directions experience an anticlockwise rotation of about 20° from eastern to central Algeria. We observe that the difference between the direction of sigma1 and the direction of convergence decreases towards the west. In central Algeria, where the collision is not perturbated by edge effects, both directions are the closest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EP%26S...68..103M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EP%26S...68..103M"><span id="translatedtitle">Influence of uncertainties of the empirical models for inferring the E-<span class="hlt">region</span> electric <span class="hlt">fields</span> at the dip equator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moro, Juliano; Denardini, Clezio Marcos; Resende, Laysa Cristina Araújo; Chen, Sony Su; Schuch, Nelson Jorge</p> <p>2016-06-01</p> <p>Daytime E-<span class="hlt">region</span> electric <span class="hlt">fields</span> play a crucial role in the ionospheric dynamics at the geomagnetic dip latitudes. Due to their importance, there is an interest in accurately measuring and modeling the electric <span class="hlt">fields</span> for both climatological and near real-time studies. In this work, we present the daytime vertical ( Ez) and eastward ( Ey) electric <span class="hlt">fields</span> for a reference quiet day (February 7, 2001) at the São Luís Space Observatory, Brazil (SLZ, 2.31°S, 44.16°W). The component Ez is inferred from Doppler shifts of type II echoes (gradient drift instability) and the anisotropic factor, which is computed from ion and electron gyro frequencies as well as ion and electron collision frequencies with neutral molecules. The component Ey depends on the ratio of Hall and Pedersen conductivities and Ez. A magnetic <span class="hlt">field</span>-line-integrated conductivity model is used to obtain the anisotropic factor for calculating Ez and the ionospheric conductivities for calculating Ey. This model uses the NRLMSISE-00, IRI-2007, and IGRF-11 empirical models as input parameters for neutral atmosphere, ionosphere, and geomagnetic <span class="hlt">field</span>, respectively. Consequently, it is worth determining the uncertainties (or errors) in Ey and Ez associated with these empirical model outputs in order to precisely define the confidence limit for the estimated electric <span class="hlt">field</span> components. For this purpose, errors of ±10 % were artificially introduced in the magnitude of each empirical model output before estimating Ey and Ez. The corresponding uncertainties in the ionospheric conductivity and electric <span class="hlt">field</span> are evaluated considering the individual and cumulative contribution of the artificial errors. The results show that the neutral densities and temperature may be responsible for the largest changes in Ey and Ez, followed by changes in the geomagnetic <span class="hlt">field</span> intensity and electron and ions compositions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22270960','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22270960"><span id="translatedtitle">TURBULENCE IN THE OUTER <span class="hlt">REGIONS</span> OF PROTOPLANETARY DISKS. II. STRONG ACCRETION DRIVEN BY A VERTICAL MAGNETIC <span class="hlt">FIELD</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Simon, Jacob B.; Armitage, Philip J.; Beckwith, Kris; Bai, Xue-Ning; Stone, James M.</p> <p>2013-09-20</p> <p>We carry out a series of local, vertically stratified shearing box simulations of protoplanetary disks that include ambipolar diffusion and a net vertical magnetic <span class="hlt">field</span>. The ambipolar diffusion profiles we employ correspond to 30 AU and 100 AU in a minimum mass solar nebula (MMSN) disk model, which consists of a far-ultraviolet-ionized surface layer and low-ionization disk interior. These simulations serve as a follow-up to Simon et al., in which we found that without a net vertical <span class="hlt">field</span>, the turbulent stresses that result from the magnetorotational instability (MRI) are too weak to account for observed accretion rates. The simulations in this work show a very strong dependence of the accretion stresses on the strength of the background vertical <span class="hlt">field</span>; as the <span class="hlt">field</span> strength increases, the stress amplitude increases. For a net vertical <span class="hlt">field</span> strength (quantified by β{sub 0}, the ratio of gas to magnetic pressure at the disk mid-plane) of β{sub 0} = 10{sup 4} and β{sub 0} = 10{sup 5}, we find accretion rates M-dot ∼10{sup -8}-10{sup –7} M{sub ☉} yr{sup –1}. These accretion rates agree with observational constraints, suggesting a vertical magnetic <span class="hlt">field</span> strength of ∼60-200 μG and 10-30 μG at 30 AU and 100 AU, respectively, in a MMSN disk. Furthermore, the stress has a non-negligible component due to a magnetic wind. For sufficiently strong vertical <span class="hlt">field</span> strengths, MRI turbulence is quenched, and the flow becomes largely laminar, with accretion proceeding through large-scale correlations in the radial and toroidal <span class="hlt">field</span> components as well as through the magnetic wind. In all simulations, the presence of a low-ionization <span class="hlt">region</span> near the disk mid-plane, which we call the ambipolar damping zone, results in reduced stresses there.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004CRGeo.336.1491P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004CRGeo.336.1491P"><span id="translatedtitle">Discovery of the largest impact crater <span class="hlt">field</span> on Earth in the Gilf Kebir <span class="hlt">region</span>, Egypt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paillou, Philippe; El Barkooky, Ahmed; Barakat, Aly; Malezieux, Jean-Marie; Reynard, Bruno; Dejax, Jean; Heggy, Essam</p> <p>2004-12-01</p> <p>Using orbital imaging radar, we have detected a large number of circular structures in the southwestern Egyptian desert, covering more than 4500 km 2 close to the Gilf Kebir plateau in sandstones of Upper Cretaceous. Fieldwork confirmed that it is a new impact crater <span class="hlt">field</span>: 13 craters from 20 m to 1 km in diameter were studied. The impact origin is confirmed by the observation of shock-related structures, such as shatter cones and planar fractures in quartz grains of breccia. Considering the extension of the crater <span class="hlt">field</span>, it was possibly created by several meteorites that broke up when entering the atmosphere. To cite this article: P. Paillou et al., C. R. Geoscience 336 (2004).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22130635','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22130635"><span id="translatedtitle">OBSERVATION OF A NON-RADIAL PENUMBRA IN A FLUX EMERGING <span class="hlt">REGION</span> UNDER CHROMOSPHERIC CANOPY <span class="hlt">FIELDS</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lim, Eun-Kyung; Yurchyshyn, Vasyl; Goode, Philip; Cho, Kyung-Suk</p> <p>2013-05-20</p> <p>The presence of a penumbra is one of the main properties of a mature sunspot, but its formation mechanism has been elusive due to a lack of observations that fully cover the formation process. Utilizing the New Solar Telescope at the Big Bear Solar Observatory, we observed the formation of a partial penumbra for about 7 hr simultaneously at the photospheric (TiO; 7057 A) and the chromospheric (H{alpha} - 1 A) spectral lines with high spatial and temporal resolution. From this uninterrupted, long observing sequence, we found that the formation of the observed penumbra was closely associated with flux emergence under the pre-existing chromospheric canopy <span class="hlt">fields</span>. Based on this finding, we suggest a possible scenario for penumbra formation in which a penumbra forms when the emerging flux is constrained from continuing to emerge, but rather is trapped at the photospheric level by the overlying chromospheric canopy <span class="hlt">fields</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7244705','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/7244705"><span id="translatedtitle">Health assessment for Middletown Air <span class="hlt">Field</span>, Middletown, Pennsylvania, <span class="hlt">Region</span> 3. CERCLIS No. PAD980538763. Final report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1988-04-01</p> <p>The Middletown Air <span class="hlt">Field</span> is located southeast of Harrisburg, Pennsylvania. Past waste disposal activities at the Middletown Air <span class="hlt">Field</span> have resulted in contamination of the groundwater aquifer with trichloroethylene (TCE), tetrachloroethylene (PCE), and other volatile organic chemicals (VOCs). Since 1983, the selective pumping of wells and periodic monitoring of water from the wells and distribution system have maintained VOC concentrations in finished water below acceptable health-based values. It is not possible to assess potential health effects that may have resulted from exposure to VOCs in potable water prior to 1983 because of the lack of data. Additional studies are needed to determine whether there is any human exposure to contamination sources from private potable wells or through other routes of exposure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996SoPh..166..261L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996SoPh..166..261L"><span id="translatedtitle">Rotation of the Large-Scale Solar Magnetic <span class="hlt">Fields</span> in the Equatorial <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Latushko, S.</p> <p>1996-07-01</p> <p>A study is made of the rotation of large-scale magnetic <span class="hlt">fields</span> using the synoptic maps from the Kitt Peak National Observatory for the time interval 1976 1985. The auto-correlation method and the mass-centers method of magnetic structures was applied to infer mean differential rotation profiles and rotation profiles separately for each magnetic <span class="hlt">field</span> polarity. It has been found that in both hemispheres the leading polarity rotates faster than the following polarity at all latitudes by about 0.04° day-1. The maximum rotation rate of the leading polarity is reached at about 6° latitude. In the mean profile for both polarities, this brings about two angular velocity maxima at 6° latitudes in both hemispheres. Such a profile appears as to have a ‘dimple’ on the equator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19950040055&hterms=high+frequency+magnetic+field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dhigh%2Bfrequency%2Bmagnetic%2Bfield','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19950040055&hterms=high+frequency+magnetic+field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dhigh%2Bfrequency%2Bmagnetic%2Bfield"><span id="translatedtitle">Coronal temperature, density, and magnetic <span class="hlt">field</span> maps of a solar acitve <span class="hlt">region</span> using the Owens Valley Solar Array</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gary, Dale E.; Hurford, G. J.</p> <p>1994-01-01</p> <p>We present the first results of solar active <span class="hlt">region</span> observations with the recently completed five-element Owens Valley Solar Array. On 1991 October 24, maps of Active <span class="hlt">Region</span> AR 6891 were obtained at 22 frequencies from 1.2-7.0 GHz to provide brightness temperature spectra at each point. This is the first time that both high spatial and frequency-resolution brightness temperature spectra have been available over such a broad radio-frequency range. We find that over most of the <span class="hlt">region</span> the spectra fall into one of the two well-defined categories: thermal free-free or thermal gyroresonance. In these cases, we use the spectra to deduce the spatial variation of physical parameters-electron temperature, column emission measure (intergral n(sup 2)(sub e) dl), and the coronal magnetic <span class="hlt">field</span> strength-in and around the active <span class="hlt">region</span>. Over a limited area of the <span class="hlt">region</span>, the spectra resemble neither of the simple types, and alternative interpretations are required. The possibilties include the presence of fine structure that is unresolved at low frequencies; the presence of a small number of nonthermal electrons; or the presence of overlying, cooler 10(exp 6) K material which at low frequencies absorbs the hot (3 x 10(exp 6) K) thermal emission generated below.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413264M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413264M"><span id="translatedtitle">Possible variations of E-layer electromagnetic <span class="hlt">fields</span> by acoustic waves above earthquake preparation <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meister, C.-V.; Mayer, B.; Hoffmann, D. H. H.</p> <p>2012-04-01</p> <p>The many-fluid magnetohydrodynamic theory is applied to describe the modification of the electromagnetic <span class="hlt">field</span> of the ionospheric E-layer by acoustic-type waves. These waves originate from lower altitudes and may be caused by earthquake preparation processes. In comparison to former works, the different stratification of the positively and negatively charged ionospheric particles and of the neutral constituents is taken into account. There also the influence of the mean electric <span class="hlt">field</span> on the different hight scales of the plasma parameters is discussed. Besides, the hight scales of the electric and magnetic wave <span class="hlt">fields</span> are modeled. It is shown that at E-layer altitudes the acoustic waves may be converted into Alfvén waves. The dependence of these waves on the height scales of the plasma parameters of the particles and on the momentum transport between the charged and neutral particles is analysed. First estimates of the temperature variations within the E-layer because of the assumed acoustic-type waves of seismic origin are made.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.458..855C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.458..855C"><span id="translatedtitle">Integral <span class="hlt">field</span> spectroscopy of the circum-nuclear <span class="hlt">region</span> of the radio Galaxy Pictor A</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Couto, Guilherme S.; Storchi-Bergmann, Thaisa; Robinson, Andrew; Riffel, Rogemar A.; Kharb, Preeti; Lena, Davide; Schnorr-Müller, Allan</p> <p>2016-05-01</p> <p>We present optical integral <span class="hlt">field</span> spectroscopy of the inner 2.5 × 3.4 kpc2 of the broad-line radio galaxy Pictor A, at a spatial resolution of ≈400 pc. Line emission is observed over the whole <span class="hlt">field</span> of view, being strongest at the nucleus and in an elongated linear feature (ELF) crossing the nucleus from the south-west to the north-east along PA ≈70°. Although the broad double-peaked Hα line and the [O I]6300/Hα and [S II]6717+31/Hα ratios are typical of active galactic nuclei (AGNs), the [N II]6584/Hα ratio (0.15-0.25) is unusually low. We suggest that this is due to the unusually low metallicity of the gas. Centroid velocity maps show mostly blueshifts to the south and redshifts to the north of the nucleus, but the velocity <span class="hlt">field</span> is not well fitted by a rotation model. Velocity dispersions are low (<100 km s- 1 ) along the ELF, ruling out a jet-cloud interaction as the origin of this structure. The ELF shows both blueshifts and redshifts in channel maps, suggesting that it is close to the plane of the sky. The ELF is evidently photoionized by the AGN, but its kinematics and inferred low metallicity suggest that this structure may have originated in a past merger event with another galaxy. We suggest that the gas acquired in this interaction may be feeding the ELF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22408228','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22408228"><span id="translatedtitle">Inhomogeneities of plasma density and electric <span class="hlt">field</span> as sources of electrostatic turbulence in the auroral <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ilyasov, Askar A.; Chernyshov, Alexander A. Mogilevsky, Mikhail M.; Golovchanskaya, Irina V. Kozelov, Boris V.</p> <p>2015-03-15</p> <p>Inhomogeneities of plasma density and non-uniform electric <span class="hlt">fields</span> are compared as possible sources of a sort of electrostatic ion cyclotron waves that can be identified with broadband extremely low frequency electrostatic turbulence in the topside auroral ionosphere. Such waves are excited by inhomogeneous energy-density-driven instability. To gain a deeper insight in generation of these waves, computational modeling is performed with various plasma parameters. It is demonstrated that inhomogeneities of plasma density can give rise to this instability even in the absence of electric <span class="hlt">fields</span>. By using both satellite-observed and model spatial distributions of plasma density and electric <span class="hlt">field</span> in our modeling, we show that specific details of the spatial distributions are of minor importance for the wave generation. The solutions of the nonlocal inhomogeneous energy-density-driven dispersion relation are investigated for various ion-to-electron temperature ratios and directions of wave propagation. The relevance of the solutions to the observed spectra of broadband extremely low frequency emissions is shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...824..141G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...824..141G"><span id="translatedtitle">L1599B: Cloud Envelope and C+ Emission in a <span class="hlt">Region</span> of Moderately Enhanced Radiation <span class="hlt">Field</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goldsmith, Paul F.; Pineda, Jorge L.; Langer, William D.; Liu, Tie; Requena-Torres, Miguel; Ricken, Oliver; Riquelme, Denise</p> <p>2016-06-01</p> <p>We study the effects of an asymmetric radiation <span class="hlt">field</span> on the properties of a molecular cloud envelope. We employ observations of carbon monoxide (12CO and 13CO), atomic carbon, ionized carbon, and atomic hydrogen to analyze the chemical and physical properties of the core and envelope of L1599B, a molecular cloud forming a portion of the ring at ≃27 pc from the star Λ Ori. The O8 star provides an asymmetric radiation <span class="hlt">field</span> that produces a moderate enhancement of the external radiation <span class="hlt">field</span>. Observations of the [C ii] fine structure line with the GREAT instrument on SOFIA indicate a significant enhanced emission on the side of the cloud facing the star, while the [C i], 12CO and 13CO J = 1–0 and 2–1, and 12CO J = 3–2 data from the Purple Mountain Observatory and APEX telescopes suggest a relatively typical cloud interior. The atomic, ionic, and molecular line centroid velocities track each other very closely, and indicate that the cloud may be undergoing differential radial motion. The H i data from the Arecibo GALFA survey and the SOFIA/GREAT [C ii] data do not suggest any systematic motion of the halo gas, relative to the dense central portion of the cloud traced by 12CO and 13CO.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM23D..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM23D..06S"><span id="translatedtitle">Structure and Dynamics of the Sub-corotating <span class="hlt">Region</span> of Saturn's Magnetosphere: Cassini Magnetic <span class="hlt">Field</span> Observations.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, E. J.; Dougherty, M. K.</p> <p>2014-12-01</p> <p>Measurements of the azimuthal magnetic <span class="hlt">field</span> component, BΦ, enable the study of the sub-corotating magnetosphere, the associated global current system, the ionospheric Pedersen current, IP, and a comparison with the Cowley-Vasyliunas model. The study is strongly dependent on Cassini's highly elliptical orbits that restrict useful observations to specific orbits and parts of orbits to avoid weak azimuthal <span class="hlt">fields</span> associated with the magnetopause or other magnetospheric currents. An example is the selection of thirteen identical orbits near 22 +/- 2 hours Local Time and restriction of the data to 4 to 10 Saturn radii. Inferred IP profiles between 10° and 25° ionospheric co-latitude, θi , when averaged, are similar in shape to model predictions with a peak value of 5 million amperes. However, the individual profiles vary significantly, the result of dynamics associated with large-scale motions of the magnetospheric <span class="hlt">field</span>. The Cowley-Vasyliunas model also relates IP(θi) to magnetospheric rotation rates, ΩS, equivalent to the SKR period, and the sub-corotation rate, ω, and provides a means of estimating ω / ΩS in the night-side magnetosphere as compared to the dayside rotation rates obtained from azimuthal plasma velocity measurements, VΦ. Other carefully- selected orbits extend these results to different ranges in θi and Local Times and provide further values of important magnetospheric parameters and allow additional testing of the model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRB..120.2600M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRB..120.2600M"><span id="translatedtitle">Relationships among seismic velocity, metamorphism, and seismic and aseismic fault slip in the Salton Sea Geothermal <span class="hlt">Field</span> <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McGuire, Jeffrey J.; Lohman, Rowena B.; Catchings, Rufus D.; Rymer, Michael J.; Goldman, Mark R.</p> <p>2015-04-01</p> <p>The Salton Sea Geothermal <span class="hlt">Field</span> is one of the most geothermally and seismically active areas in California and presents an opportunity to study the effect of high-temperature metamorphism on the properties of seismogenic faults. The area includes numerous active tectonic faults that have recently been imaged with active source seismic reflection and refraction. We utilize the active source surveys, along with the abundant microseismicity data from a dense borehole seismic network, to image the 3-D variations in seismic velocity in the upper 5 km of the crust. There are strong velocity variations, up to ~30%, that correlate spatially with the distribution of shallow heat flow patterns. The combination of hydrothermal circulation and high-temperature contact metamorphism has significantly altered the shallow sandstone sedimentary layers within the geothermal <span class="hlt">field</span> to denser, more feldspathic, rock with higher P wave velocity, as is seen in the numerous exploration wells within the <span class="hlt">field</span>. This alteration appears to have a first-order effect on the frictional stability of shallow faults. In 2005, a large earthquake swarm and deformation event occurred. Analysis of interferometric synthetic aperture radar data and earthquake relocations indicates that the shallow aseismic fault creep that occurred in 2005 was localized on the Kalin fault system that lies just outside the <span class="hlt">region</span> of high-temperature metamorphism. In contrast, the earthquake swarm, which includes all of the M > 4 earthquakes to have occurred within the Salton Sea Geothermal <span class="hlt">Field</span> in the last 15 years, ruptured the Main Central Fault (MCF) system that is localized in the heart of the geothermal anomaly. The background microseismicity induced by the geothermal operations is also concentrated in the high-temperature <span class="hlt">regions</span> in the vicinity of operational wells. However, while this microseismicity occurs over a few kilometer scale <span class="hlt">region</span>, much of it is clustered in earthquake swarms that last from hours to a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Tectp.608..980K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Tectp.608..980K"><span id="translatedtitle">Seismotectonics of the Armutlu peninsula (Marmara Sea, NW Turkey) from geological <span class="hlt">field</span> observation and <span class="hlt">regional</span> moment tensor inversion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kinscher, J.; Krüger, F.; Woith, H.; Lühr, B. G.; Hintersberger, E.; Irmak, T. S.; Baris, S.</p> <p>2013-11-01</p> <p>The Armutlu peninsula, located in the eastern Marmara Sea, coincides with the western end of the rupture of the 17 August 1999, İzmit MW 7.6 earthquake which is the penultimate event of an apparently westward migrating series of strong and disastrous earthquakes along the NAFZ during the past century. We present new seismotectonic data of this key <span class="hlt">region</span> in order to evaluate previous seismotectonic models and their implications for seismic hazard assessment in the eastern Marmara Sea. Long term kinematics were investigated by performing paleo strain reconstruction from geological <span class="hlt">field</span> investigations by morphotectonic and kinematic analysis of exposed brittle faults. Short term kinematics were investigated by inverting for the moment tensor of 13 small to moderate recent earthquakes using surface wave amplitude spectra. Our results confirm previous models interpreting the eastern Marmara Sea <span class="hlt">Region</span> as an active transtensional pull-apart environment associated with significant NNE-SSW extension and vertical displacement. At the northern peninsula, long term deformation pattern did not change significantly since Pliocene times contradicting <span class="hlt">regional</span> tectonic models which postulate a newly formed single dextral strike slip fault in the Marmara Sea <span class="hlt">Region</span>. This area is interpreted as a horsetail splay fault structure associated with a major normal fault segment that we call the Waterfall Fault. Apart from the Waterfall Fault, the stress strain relation appears complex associated with a complicated internal fault geometry, strain partitioning, and reactivation of pre-existing plane structures. At the southern peninsula, recent deformation indicates active pull-apart tectonics constituted by NE-SW trending dextral strike slip faults. Earthquakes generated by stress release along large rupture zones seem to be less probable at the northern, but more probable at the southern peninsula. Additionally, <span class="hlt">regional</span> seismicity appears predominantly driven by plate boundary</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EGUGA..18.9494V&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EGUGA..18.9494V&link_type=ABSTRACT"><span id="translatedtitle">Celtic <span class="hlt">field</span> agriculture and Early Anthropogenic Environmental change in the Meuse-Demer-Scheldt <span class="hlt">region</span>, NW Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Van der Sanden, Germaine; Kluiving, Sjoerd; Roymans, Nico</p> <p>2016-04-01</p> <p>The <span class="hlt">field</span> of Archaeology remains focused on historical issues while underexploring its potential contribution on currently existing societal problems, e.g. climate change. The aim of this paper is to show the relevance of archeological studies for the research of the 'human species as a significant moving agent' in terms of the changing natural environment during a much earlier time frame. This research is based on the study area of the Meuse-Demer-Scheldt <span class="hlt">region</span> in the Netherlands and Belgium and exhibits the period from the Late Bronze Age to the Early Roman period. This period is characterized by the widespread introduction and use of an agricultural system, often referred to as the Celtic <span class="hlt">Field</span> system that served as one of the most modifying systems in terms of anthropogenic-environmental change during this period. Emphasis in this research is given to results generated by the use of the remote sensing technology, LiDAR. New information is reported considering a correlation between singular <span class="hlt">field</span> size and the overall surface of the agricultural complexes and secondly, the presentation of newly identified Celtic <span class="hlt">field</span> systems in the Meuse-Demer-Scheldt <span class="hlt">region</span> are presented. The study of the dynamics of the Celtic <span class="hlt">Field</span> agricultural system provides evidence for a significant anthropogenic footprint on the natural environment due to land cover dominance, soil degeneration, increased soil acidification and forest clearance. Soil exhaustion forced the inhabitants to re-establish their relationship with the landscape in terms of fundamental changes in the habitation pattern and the agrarian exploitations of the land.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7621P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7621P"><span id="translatedtitle">Agricultural terraces montoring and modeling: a <span class="hlt">field</span> survey in Chianti <span class="hlt">region</span>, Firenze, Italy - First part</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Preti, Federico; Caruso, Marco; Dani, Andrea; Errico, Alessandro; Guastini, Enrico; Trucchi, Paolo</p> <p>2015-04-01</p> <p>The two abstracts present the design and set-up of an experimental <span class="hlt">field</span> plant whose aim is the study and modeling of water circulation in a terraced slope together with its influence on the stability of the retaining dry stone walls. The pilot plant is located at "Fattoria di Lamole" (Greve in Chianti, Firenze, Italy) where both ancient and recently restored or rebuilt dry stone retaining walls are present. The intense vineyards cultivation makes it very representative in terms of range of external stresses that affect both hillslopes and walls. The research is developed within a bigger framework of landscape preservation as a way to prevent hydrogeological instabilities and landslide risks. First Part A first/preliminary <span class="hlt">field</span> survey was carried out in order to estimate the hydraulic and mechanical soil characteristics. <span class="hlt">Field</span> saturated hydraulic conductivity measurements with the Simplified Falling Head (SFH) method on a terrace along an alignment were performed. Infiltrometer tests with a double ring device and soil texture determinations with both fine particle-size and skeleton fraction distributions were also performed. The Direct shear test on undisturbed and reconstituted soil samples will offer an estimation of the Mohr-Coulomb failure envelope parameters (friction angle and cohesion). A reference portion of a dry stone wall will be also monitored. Lateral earth pressure at backfill-retaining wall interface (compared to temperature and air pressure measured values), backfill volumetric water content (both in saturated and unsaturated states) and ground-water level are measured. Acknowledgements Italian Research Project of Relevant Interest (PRIN2010-2011), prot. 20104ALME4, National network for monitoring, modeling, and sustainable management of erosion processes in agricultural land and hilly-mountainous area</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SGeo...36..773B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SGeo...36..773B"><span id="translatedtitle">Global and <span class="hlt">Regional</span> Gravity <span class="hlt">Field</span> Determination from GOCE Kinematic Orbit by Means of Spherical Radial Basis Functions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bucha, Blažej; Bezděk, Aleš; Sebera, Josef; Janák, Juraj</p> <p>2015-11-01</p> <p>We present global and <span class="hlt">regional</span> gravity <span class="hlt">field</span> models to degree 130 based on the GOCE kinematic orbit from the period 01 November 2009 to 11 January 2010. The gravity <span class="hlt">field</span> models are parameterized in terms of the Shannon and Kaula's spherical radial basis functions. The relation between the unknown expansion coefficients and the kinematic orbit of the satellite is established by the acceleration approach. We show that our global GOCE-only solutions free from prior information can compete with unconstrained spherical harmonic models in terms of accuracy. Furthermore, we utilize our low-degree global GOCE-based models to introduce prior information into the least-squares adjustment. This procedure substantially improves the zonal and near-zonal spherical harmonic coefficients, which are usually degraded due to the polar gap problem. As an unwanted side effect, low-pass filtering of the geopotential may occur, but this can be adjusted by the spectral content of the prior information. We show that the <span class="hlt">regional</span> enhancement of the global solutions reduces noise in the final model between degrees 70 and 130 by ~10 % in terms of RMS error. In general, our Shannon-based solutions systematically outperform the Kaula-based ones. To validate our results, we use the EIGEN-6S model, which is superior to the solutions from kinematic orbits at least by one order of magnitude. Both the global and the <span class="hlt">regional</span> models satisfy the GOCE-only strategy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70017507','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70017507"><span id="translatedtitle">Surficial geology of the Safsaf <span class="hlt">region</span>, south-central Egypt, derived from remote-sensing and <span class="hlt">field</span> data</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Davis, P.A.; Breed, C.S.; McCauley, J.F.; Schaber, G.G.</p> <p>1993-01-01</p> <p>We used a decorrelation-stretched image of Landsat Thematic Mapper (TM) Bands 1, 4, and 7 and <span class="hlt">field</span> data to map and describe the main surficial units in the hyperarid Safsaf <span class="hlt">region</span> in south-central Egypt. We show that the near-infrared bands on Landsat TM, which are sensitive to very subtle changes in mineralogy common to arid <span class="hlt">regions</span>, significantly improve the geologist's capability to discriminate geologic units in desert <span class="hlt">regions</span>. These data also provide the spatial and spectral information necessary to determine the migration patterns and provenance of eolian materials. The Safsaf area was the focus of our post flight <span class="hlt">field</span> studies using Shuttle Imaging Radar (SIR) data following the discovery of buried paleochannels in North Africa. Most of the channels discernible on SIR images are not expressed in TM data, but traces of a few channels are present in both the SIR and the TM data within the Wadi Safsaf area. Here we present a detailed digital examination of the SIR and the TM-band reflectance and reflectance-ratio data at three locations of the more obvious surface expressions of the buried channels. Our results indicate that the TM expressions of the channels are not purely topographic but are more compositional in nature. Two possibilities may account for the TM expressions of the buried channels: 1) concentrations of windblown, iron-rich materials that accumulated along subtle curvilinear topograpohic traps, or 2) curvilinear exposures of an iron-rich underlying unit of the flat sand sheet. ?? 1993.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016AtmRe.167...89W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016AtmRe.167...89W&link_type=ABSTRACT"><span id="translatedtitle">Impacts of cloud overlap assumptions on radiative budgets and heating <span class="hlt">fields</span> in convective <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, XiaoCong; Liu, YiMin; Bao, Qing</p> <p>2016-01-01</p> <p>Impacts of cloud overlap assumptions on radiative budgets and heating <span class="hlt">fields</span> are explored with the aid of a cloud-resolving model (CRM), which provided cloud geometry as well as cloud micro and macro properties. Large-scale forcing data to drive the CRM are from TRMM Kwajalein Experiment and the Global Atmospheric Research Program's Atlantic Tropical Experiment <span class="hlt">field</span> campaigns during which abundant convective systems were observed. The investigated overlap assumptions include those that were traditional and widely used in the past and the one that was recently addressed by Hogan and Illingworth (2000), in which the vertically projected cloud fraction is expressed by a linear combination of maximum and random overlap, with the weighting coefficient depending on the so-called decorrelation length Lcf. Results show that both shortwave and longwave cloud radiative forcings (SWCF/LWCF) are significantly underestimated under maximum (MO) and maximum-random (MRO) overlap assumptions, whereas remarkably overestimated under the random overlap (RO) assumption in comparison with that using CRM inherent cloud geometry. These biases can reach as high as 100 Wm- 2 for SWCF and 60 Wm- 2 for LWCF. By its very nature, the general overlap (GenO) assumption exhibits an encouraging performance on both SWCF and LWCF simulations, with the biases almost reduced by 3-fold compared with traditional overlap assumptions. The superiority of GenO assumption is also manifested in the simulation of shortwave and longwave radiative heating <span class="hlt">fields</span>, which are either significantly overestimated or underestimated under traditional overlap assumptions. The study also pointed out the deficiency of constant assumption on Lcf in GenO assumption. Further examinations indicate that the CRM diagnostic Lcf varies among different cloud types and tends to be stratified in the vertical. The new parameterization that takes into account variation of Lcf in the vertical well reproduces such a relationship and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960029045','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960029045"><span id="translatedtitle">Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis <span class="hlt">Region</span> and <span class="hlt">Field</span> Trips in the Channeled Scabland, Washington</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W. , Jr. (Editor)</p> <p>1995-01-01</p> <p>Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of <span class="hlt">field</span> trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis <span class="hlt">Region</span> and <span class="hlt">Field</span> Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis <span class="hlt">region</span> on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The <span class="hlt">field</span> trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The <span class="hlt">field</span> trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and <span class="hlt">field</span> trip guides for the overflight and two <span class="hlt">field</span> trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the <span class="hlt">field</span> trips and ensuing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/862406','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/862406"><span id="translatedtitle">Chiral Effective-<span class="hlt">Field</span> Theory in the $\\Delta$(1232) <span class="hlt">Region</span>: I. Pion Electroproduction on the Nucleon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vladimir Pascalutsa; Marc Vanderhaeghen</p> <p>2006-01-20</p> <p>We develop an extension of chiral perturbation theory to the {Delta}(1232)-resonance energy <span class="hlt">region</span> and apply it to investigate the pion electroproduction off the nucleon (e{sup -} N {yields} e{sup -} N {pi}). We present a complete calculation of this process, in the {Delta}-resonance <span class="hlt">region</span>, up to next-to-leading order in the {delta}-expansion. At this order, the only free parameters are the three low-energy constants corresponding to the magnetic (M1), electric (E2), and Coulomb (C2) {gamma} N {yields} {Delta} transition strength. After fitting these parameters to a few well-known data, our calculation provides a prediction for observables and multipole amplitudes of pion electroproduction. These results compare favorably with the phenomenological multipole solutions and recent experimental results from MIT-Bates and MAMI. Our prediction for the pion-mass dependence of the {gamma}N{Delta} form factors offers an explanation for the discrepancy between the recent lattice-QCD results and the experimental value for the ''C2/M1 ratio'' at low Q{sup 2}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4078593','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4078593"><span id="translatedtitle"><span class="hlt">Field</span> Survey of Health Perception and Complaints of Pennsylvania Residents in the Marcellus Shale <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Saberi, Pouné; Propert, Kathleen Joy; Powers, Martha; Emmett, Edward; Green-McKenzie, Judith</p> <p>2014-01-01</p> <p>Pennsylvania Marcellus Shale <span class="hlt">region</span> residents have reported medical symptoms they believe are related to nearby Unconventional Natural Gas Development (UNGD). Associations between medical symptoms and UNGD have been minimally explored. The objective of this descriptive study is to explore whether shale <span class="hlt">region</span> Pennsylvania residents perceive UNGD as a health concern and whether they attribute health symptoms to UNGD exposures. A questionnaire was administered to adult volunteers with medical complaints in a primary-care medical office in a county where UNGD was present. Participants were asked whether they were concerned about health effects from UNGD, and whether they attributed current symptoms to UNGD or to some other environmental exposure. There were 72 respondents; 22% perceived UNGD as a health concern and 13% attributed medical symptoms to UNGD exposures. Overall, 42% attributed one or more of their medical symptoms to environmental causes, of which UNGD was the most frequent. A medical record review conducted on six participants who attributed their medical symptoms to UNGD revealed that only one of these records documented both the symptoms in question and the attribution to UNGD. The results of this pilot study suggest that there is substantial concern about adverse health effects of UNGD among Pennsylvania Marcellus Shale residents, and that these concerns may not be adequately represented in medical records. Further efforts to determine the relationship between UNGD and health are recommended in order to address community concerns. PMID:25003172</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/7721059','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/7721059"><span id="translatedtitle">[Nucleolus organizer <span class="hlt">regions</span> and B-chromosomes of <span class="hlt">field</span> mice (Mammalia, Rodentia, Apodemus)].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Boeskorov, G G; Kartavtseva, I V; Zagorodniuk, I V; Belianin, A N; Liapunova, E A</p> <p>1995-02-01</p> <p>Distribution of nucleolus organizer <span class="hlt">regions</span> (NORs) in karyotypes was studied in 10 species of wood mice, including Apodemus flavicollis, A. sylvaticus, A. uralensis (= A. microps), A. fulvipectus (= A. falzfeini), A. ponticus, A. hyrcanicus, A. mystacinus, A. agrarius, A. peninsulae, and A. speciosus. Peculiarities of NOR location in karyotypes can be used in interspecific diagnostics of wood mice. Intraspecific polymorphism of A. sylvaticus, A. agrarius, and A. peninsulae in terms of the number of NORs and their localization in chromosomes can serve as evidence for karyological differentiation in certain populations of these species. The minimum number of active NORs in mice of the genus Apodemus is two to four. Two A. flavicollis wood mice with karyotypes containing one small acrocentric B-chromosome (2n = 49) were identified among animals captured in Estonia. In A. peninsulae, B-chromosomes were found among animals captured in the following <span class="hlt">regions</span>: the vicinity of Kyzyl (one mouse with 17 microchromosomes, 2n = 65); the vicinity of Birakan (two mice with one metacentric chromosome each, 2n = 49); and in the Ussuri Nature Reserve (one mouse with five B-chromosomes, including three metacentric and two dotlike chromosomes; 2n = 65). In the latter animal, the presence of NORs on two metacentric B-chromosomes was revealed; this is the first case of identification of active NORs on extra chromosomes of mammals. PMID:7721059</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRA..108.1254A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRA..108.1254A"><span id="translatedtitle">Equatorial evening prereversal electric <span class="hlt">field</span> enhancement and sporadic E layer disruption: A manifestation of E and F <span class="hlt">region</span> coupling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdu, M. A.; MacDougall, J. W.; Batista, I. S.; Sobral, J. H. A.; Jayachandran, P. T.</p> <p>2003-06-01</p> <p>An investigation of the evening prereversal enhancement in the equatorial zonal electric <span class="hlt">field</span> (PRE) based on ionosonde data show that the PRE development process is coupled with the sporadic E layer formation in the evening over Fortaleza. Larger PRE amplitudes are associated with disruption of the Es layer, whereas for smaller PRE amplitudes such disruption does not occur, in general. The Es layer disruption does not occur also when the PRE amplitude decreases or is inhibited under a disturbance dynamo electric <span class="hlt">field</span>. The disruption of these layers is followed by their reconstitution after a break of ˜3 hours. An examination of the relative role of the electric <span class="hlt">field</span> and winds on ion velocity convergence process shows that the Es layer formation from a shearing (or height-independent and westward) zonal wind is directly influenced by a vertical electric <span class="hlt">field</span> (but not by zonal electric <span class="hlt">field</span>). Measurements of the Es patch zonal drift velocities by a digital ionosonde seem to support the role of a westward wind in the Es layer formation. The observed association between the PRE and Es layer disruption/formation is shown to arise from sunset-related vertical electric <span class="hlt">field</span> development originating from the E and F <span class="hlt">region</span> electrodynamic coupling processes. The results demonstrate the competing influences of the vertical electric <span class="hlt">field</span> and the zonal wind in the evening Es layer processes. Since the PRE is responsible for the equatorial spread F (ESF) development, its relationship with the Es layer is discussed in the context of the day-to-day variability of the ESF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22351583','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22351583"><span id="translatedtitle">Using coronal loops to reconstruct the magnetic <span class="hlt">field</span> of an active <span class="hlt">region</span> before and after a major flare</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Malanushenko, A.; Schrijver, C. J.; DeRosa, M. L.; Wheatland, M. S.</p> <p>2014-03-10</p> <p>The shapes of solar coronal loops are sensitive to the presence of electrical currents that are the carriers of the non-potential energy available for impulsive activity. We use this information in a new method for modeling the coronal magnetic <span class="hlt">field</span> of active <span class="hlt">region</span> (AR) 11158 as a nonlinear force-free <span class="hlt">field</span> (NLFFF). The observations used are coronal images around the time of major flare activity on 2011 February 15, together with the surface line-of-sight magnetic <span class="hlt">field</span> measurements. The data are from the Helioseismic and Magnetic Imager and Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. The model <span class="hlt">fields</span> are constrained to approximate the coronal loop configurations as closely as possible, while also being subject to the force-free constraints. The method does not use transverse photospheric magnetic <span class="hlt">field</span> components as input and is thereby distinct from methods for modeling NLFFFs based on photospheric vector magnetograms. We validate the method using observations of AR 11158 at a time well before major flaring and subsequently review the <span class="hlt">field</span> evolution just prior to and following an X2.2 flare and associated eruption. The models indicate that the energy released during the instability is about 1 × 10{sup 32} erg, consistent with what is needed to power such a large eruptive flare. Immediately prior to the eruption, the model <span class="hlt">field</span> contains a compact sigmoid bundle of twisted flux that is not present in the post-eruption models, which is consistent with the observations. The core of that model structure is twisted by ≈0.9 full turns about its axis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25679690','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25679690"><span id="translatedtitle">Classical dynamics and localization of resonances in the high-energy <span class="hlt">region</span> of the hydrogen atom in crossed <span class="hlt">fields</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schweiner, Frank; Main, Jörg; Cartarius, Holger; Wunner, Günter</p> <p>2015-01-01</p> <p>When superimposing the potentials of external <span class="hlt">fields</span> on the Coulomb potential of the hydrogen atom, a saddle point (called the Stark saddle point) appears. For energies slightly above the saddle point energy, one can find classical orbits that are located in the vicinity of this point. We follow those so-called quasi-Penning orbits to high energies and <span class="hlt">field</span> strengths, observing structural changes and uncovering their bifurcation behavior. By plotting the stability behavior of those orbits against energy and <span class="hlt">field</span> strength, the appearance of a stability apex is reported. A cusp bifurcation, located in the vicinity of the apex, will be investigated in detail. In this cusp bifurcation, another orbit of similar shape is found. This orbit becomes completely stable in the observed <span class="hlt">region</span> of positive energy, i.e., in a <span class="hlt">region</span> of parameter space, where the Kepler-like orbits located around the nucleus are already unstable. By quantum mechanically exact calculations, we prove the existence of signatures in quantum spectra belonging to those orbits. Husimi distributions are used to compare quantum-Poincaré sections with the extension of the classical torus structure around the orbits. Since periodic orbit theory predicts that each classical periodic orbit contributes an oscillating term to photoabsorption spectra, we finally give an estimation for future experiments, which could verify the existence of the stable orbits. PMID:25679690</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMSA22A..02O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMSA22A..02O"><span id="translatedtitle">Radar and Optical Observation of Medium-Scale Traveling Ionospheric Disturbances and <span class="hlt">Field</span>-Aligned Irregularities in the F <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otsuka, Y.; Yokoyama, T.; Shiokawa, K.; Ogawa, T.; Yamamoto, M.</p> <p>2007-05-01</p> <p>We report for the first time simultaneous observation of Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) and <span class="hlt">Field</span>-Aligned Irregularities (FAIs) in the F <span class="hlt">region</span> using two all-sky airglow imagers and the MU radar in Japan. The all-sky imagers were operated at Sakata (39.0°N, 139.9°E) and Shigaraki (34.9°N, 136.1°E), Japan. MSTID propagating southwestward was simultaneously observed in 630- nm airglow images at the both sites. To investigate spatial relationship between MSTID and FAIs, FAIs were mapped onto the 630-nm airglow layer (260 km altitude). Altitude of the airglow layer was estimated by the triangulation using all-sky images at Sata and Shigaraki. FAIs with strong echo intensity and upward Doppler velocities coincided with the airglow depleted <span class="hlt">region</span> due to the MSTIDs. On the other hand, FAIs with weak echo intensity and downward Doppler velocities coincided with the airglow enhancement. The directions of the Doppler velocities is consistent with that of ExB drifts caused by the polarization electric <span class="hlt">fields</span> associated with the MSTIDs. A model calculation was carried out to simulate electron density perturbations caused by oscillating electric <span class="hlt">fields</span> due to MSTIDs. The result suggests that FAIs could be generated by the gradient drift instability which operates at the spatial gradient of the electron density associated with the MSTIDs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19900048604&hterms=strength+enhancement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dstrength%2Benhancement','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19900048604&hterms=strength+enhancement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dstrength%2Benhancement"><span id="translatedtitle">Relationship of magnetic <span class="hlt">field</span> strength and brightness of fine-structure elements in the solar temperature minimum <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cook, J. W.; Ewing, J. A.</p> <p>1990-01-01</p> <p>A quantitative relationship was determined between magnetic <span class="hlt">field</span> strength (or magnetic flux) from photospheric magnetograph observations and the brightness temperature of solar fine-structure elements observed at 1600 A, where the predominant flux source is continuum emission from the solar temperature minimum <span class="hlt">region</span>. A Kitt Peak magnetogram and spectroheliograph observations at 1600 A taken during a sounding rocket flight of the High Resolution Telescope and Spectrograph from December 11, 1987 were used. The statistical distributions of brightness temperature in the quiet sun at 1600 A, and absolute value of magnetic <span class="hlt">field</span> strength in the same area were determined from these observations. Using a technique which obtains the best-fit relationship of a given functional form between these two histogram distributions, a quantitative relationship was determined between absolute value of magnetic <span class="hlt">field</span> strength B and brightness temperature which is essentially linear from 10 to 150 G. An interpretation is suggested, in which a basal heating occurs generally, while brighter elements are produced in magnetic <span class="hlt">regions</span> with temperature enhancements proportional to B.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFMSH31B..05R&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFMSH31B..05R&link_type=ABSTRACT"><span id="translatedtitle">Interchange Reconnection and Slow Solar Wind Formation at the boundaries of open <span class="hlt">field</span> <span class="hlt">regions</span> in the Solar Corona</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rappazzo, A. F.; Matthaeus, W. H.; Ruffolo, D. J.; Servidio, S.; Velli, M.</p> <p>2014-12-01</p> <p>Interchange reconnection, i.e., magnetic reconnection at the interface between open and closed corona, is thought to contribute to the formation of the slowsolar wind, since it can inject the hotter and denserplasma from closed <span class="hlt">regions</span> into the heliosphere,and account for the different slow wind composition (thatis similar to the plasma of closed <span class="hlt">regions</span>) respectto the fast wind. The interchange process has mostly been investigatedfor magnetic <span class="hlt">field</span> lines with opposite polarity and null points, either for the case of counterdirected loops (e.g., Fisk et al. 1999, Fisk and Schwadron 2001), or in correspondence of null points at the apex of streamers or pseudo-streamers (e.g., Wang et al. 1998,Edmondson et al. 2010, Del Zanna et al. 2011).Magnetic reconnection can certainly occur in these configurations,but they occupy a very small volume of the corona. On the other hand component magnetic reconnection at the boundarybetween coronal holes and streamers or pseudo-streamers hasreceived less attention, even though it can occur aroundthe entire extension of such boundaries. Magnetic reconnection is at the basis of Parker'snanoflare scenario for the heating of coronal loops.Modeling such <span class="hlt">regions</span> in cartesian geometry with a strongguide <span class="hlt">field</span>, it has been shown numerically that photosphericmotions induce a magnetic fieldcomponent orthogonal to the strong axial <span class="hlt">field</span> characterizedby the presence of many current sheets, where the <span class="hlt">field</span> lines are locally oppositely directed, and can reconnect (Einaudi et al. 1996; Dmitruk and Gomez 1997).The reconnection of the orthogonal component of the magneticfield leads to a change of connectivity of the <span class="hlt">field</span> linesof the total magnetic <span class="hlt">field</span> that connect one photospheric boundaryto the other. We have shown that a similar interchange mechanismcan operate in and around the boundaries between open and closedregions inducing a continual stochastic rearrangement of connectivityeverywhere along the open-closed boundary (Rappazzo et al. 2012</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12688479','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12688479"><span id="translatedtitle">Characteristics of nitrate horizontal transport in a paddy <span class="hlt">field</span> of the Tai Lake <span class="hlt">region</span>, China.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, X M; Shen, Q R; Pan, G X; Liu, Z P</p> <p>2003-02-01</p> <p>The characteristics of nitrate horizontal transport in a major paddy soil, Wu Shan soil in the Tai Lake <span class="hlt">region</span>, were studied. The concentration of nitrate during horizontal movement decreased with the increasing in distance from the tracer source, the change following a logarithmic function. The concentration of the nitrate was strongly correlated with the soil moisture content, as an exponential function. The horizontal transport velocity of nitrate was significantly correlated with the distance of the tracer source as power function. Therefore, the velocity of nitrate horizontal transport was controlled by the concentration gradient of nitrate, and soil water potential gradient from beginning to the 20 cm mark in the horizontal column. However, the velocity of nitrate horizontal was stable beyond 20 cm, where it was controlled by soil matric potential. PMID:12688479</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SPIE.6553E..2DN','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SPIE.6553E..2DN"><span id="translatedtitle">Development of <span class="hlt">region</span> processing algorithm for HSTAMIDS: status and <span class="hlt">field</span> test results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ngan, Peter; Burke, Sean; Cresci, Roger; Wilson, Joseph N.; Gader, Paul; Ho, K. C.; Bartosz, Elizabeth; Duvoisin, Herbert</p> <p>2007-04-01</p> <p>The <span class="hlt">Region</span> Processing Algorithm (RPA) has been developed by the Office of the Army Humanitarian Demining Research and Development (HD R&D) Program as part of improvements for the AN/PSS-14. The effort was a collaboration between the HD R&D Program, L-3 Communication CyTerra Corporation, University of Florida, Duke University and University of Missouri. RPA has been integrated into and implemented in a real-time AN/PSS-14. The subject unit was used to collect data and tested for its performance at three Army test sites within the United States of America. This paper describes the status of the technology and its recent test results.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016AIPC.1758c0009S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016AIPC.1758c0009S&link_type=ABSTRACT"><span id="translatedtitle">Performances and failure of <span class="hlt">field</span>-aged PV modules operating in Saharan <span class="hlt">region</span> of Algeria</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sadok, M.; Benyoucef, B.; Othmani, M.; Mehdaoui, A.</p> <p>2016-07-01</p> <p>This article deals with behaviour of PV modules, of different technologies and manufacturers, exposed for long periods in Saharan <span class="hlt">region</span> of Algeria. These modules are exposed in Adrar in the south-western part of Algeria. The study uses experimental I-V curves of PV modules for determining their performances. The datasheet information of modules will be useful in determination of degradation rates of the modules. Three types of modules have been tested: Photowatt (PWX 500), UDTS-50 and Isofoton (I-75 and I-100 serials). Results showed that Isofoton I-100 modules present the highest degradation rate while the lowest degradation rate was reached with I-75 serial. However, these rates tallies with other studies. The visual inspection of the modules has revealed various kinds of failures and defects responsible of performances drop (EVA browning, delamination, burn marks,…).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25628100','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25628100"><span id="translatedtitle"><span class="hlt">Field</span> Test of a Hybrid Finite-Difference and Analytic Element <span class="hlt">Regional</span> Model.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Abrams, D B; Haitjema, H M; Feinstein, D T; Hunt, R J</p> <p>2016-01-01</p> <p><span class="hlt">Regional</span> finite-difference models often have cell sizes that are too large to sufficiently model well-stream interactions. Here, a steady-state hybrid model is applied whereby the upper layer or layers of a coarse MODFLOW model are replaced by the analytic element model GFLOW, which represents surface waters and wells as line and point sinks. The two models are coupled by transferring cell-by-cell leakage obtained from the original MODFLOW model to the bottom of the GFLOW model. A real-world test of the hybrid model approach is applied on a subdomain of an existing model of the Lake Michigan Basin. The original (coarse) MODFLOW model consists of six layers, the top four of which are aggregated into GFLOW as a single layer, while the bottom two layers remain part of MODFLOW in the hybrid model. The hybrid model and a refined "benchmark" MODFLOW model simulate similar baseflows. The hybrid and benchmark models also simulate similar baseflow reductions due to nearby pumping when the well is located within the layers represented by GFLOW. However, the benchmark model requires refinement of the model grid in the local area of interest, while the hybrid approach uses a gridless top layer and is thus unaffected by grid discretization errors. The hybrid approach is well suited to facilitate cost-effective retrofitting of existing coarse grid MODFLOW models commonly used for <span class="hlt">regional</span> studies because it leverages the strengths of both finite-difference and analytic element methods for predictions in mildly heterogeneous systems that can be simulated with steady-state conditions. PMID:25628100</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/11028','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/11028"><span id="translatedtitle"><span class="hlt">Regional</span>-scale influences on urban air quality : a <span class="hlt">field</span> study in Phoenix, Arizona.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gaffney, J. S.</p> <p>1998-10-12</p> <p><span class="hlt">Regional</span> air quality can play an important role in determining whether urban ozone or PM-2.5 standards are exceeded. Background levels of nitrogen oxide species (NO{sub x}) and their interactions with natural organics can generate secondary aerosol products via formation of nitric acid and its subsequent reaction with ammonia to form ammonium nitrate. Natural organics and reactive anthropogenic organic compounds, particularly aromatic species and monoterpenes, can also lead to the formation of secondary organic aerosols, contributing to the formation of PM-2.5. Long-range transport and chemical transformation of hydrocarbons and NO{sub x} via both photochemical reactions and nighttime chemistry can yield significant <span class="hlt">regional</span> levels of ozone and other oxidants, such as peroxyacyl nitrates (R-C=O-O-O-NO{sub 2}; PANs). The PANs are key species in determining the apparent age of an air parcel (Gaffney et al., 1989, 1993, 1997). The most common member of the family is peroxyacetyl nitrate (R=CH3-; PAN), which typically accounts for more than 85% of the PANs found in an urban or rural site. The PANs are in equilibrium with NO{sub 2}. Peroxyacyl radicals (R-C=O-O-O) are typically produced by the photooxidation reactions of organics, particularly those of aldehyde oxidation products with OH radical during the daytime (photochemically active) periods. Proposed mechanisms for nighttime formation of PANs (Gaffney et al., 1989) include abstraction reactions of nitrate radical (NO{sub 3}) and the initiation of OH chemistry by olefin-ozone reactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25442588','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25442588"><span id="translatedtitle">Quality traits analysis and protein profiling of <span class="hlt">field</span> pea (Pisum sativum) germplasm from Himalayan <span class="hlt">region</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sharma, Shagun; Singh, Narpinder; Virdi, Amardeep Singh; Rana, Jai Chand</p> <p>2015-04-01</p> <p>The grain and flour characteristics of different <span class="hlt">field</span> pea (FP) accessions were evaluated. Accessions with higher grain weight had less compact structure with a greater proportion of large-sized starch granules. Accessions with higher protein content had lower starch content, blue value and λ(max) whereas accessions with higher amylose showed higher resistant starch (RS) and final viscosity and lower rapidly digestible starch (RDS). Ca, Zn, K and Fe content vary significantly amongst different accessions and creamish green and white seeds accessions showed higher Fe and Zn content. Yellow coloured accessions (1.36-3.71%) showed lower antioxidant activity as compared to brownish and green coloured accessions (4.06-9.30%). Out of 21 major polypeptides observed (9-100 kDa), 11 showed differential trypsin inhibitory activity (TIA) under non-reducing conditions. Polypeptides of 68, 46, 33 and 22 kDa showed prominent TIA. PMID:25442588</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhRvA..82e5403L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhRvA..82e5403L"><span id="translatedtitle">Numerical simulation of strong-<span class="hlt">field</span> electron spectra of Xe in the rescattering <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liang, Yaqiu</p> <p>2010-11-01</p> <p>We investigate the high-energy above-threshold ionization (HATI) plateau for Xe in a strong laser <span class="hlt">field</span> at peak intensity of about 0.85×1014W/cm2 with wavelengths of 800, 1250, 1500, and 2000 nm. Numerical simulations are performed using a recently developed quantitative rescattering (QRS) model. According to the QRS model, the two-dimensional (2D) photoelectron momentum distribution can be treated as a product of the returning electron wave packet and the elastic differential cross section (DCS) for free electrons scattered with the parent ion. From the 2D momentum distributions, the HATI plateau can be obtained. By using different single-active electron potentials in the DCS calculations, we test the potential dependence of the high-energy plateau spectra. Good agreement between the simulated results and the experimental data confirms again the validity of the QRS model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PEPI..160...86B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PEPI..160...86B"><span id="translatedtitle">Investigation into the <span class="hlt">regional</span> wrench tectonics of inner East Anatolia (Turkey) using potential <span class="hlt">field</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Büyüksaraç, Aydın</p> <p>2007-01-01</p> <p>The residual aeromagnetic and gravity anomalies of inner East Anatolia, surveyed by the Mineral Research and Exploration (MTA) of Turkey, display complexities. Some faults, which are known and new lineaments, are drawn from maxspot map derived from the location of the horizontal gradient of gravity anomalies. Tectonic lineaments of inner East Anatolia exhibit similarities to the direction of East Anatolian Fault Zone. Anticlockwise rotation, approximately -30°, defined from disorientations of aeromagnetic anomalies. The lineaments obtained from maxspots map produced from the gravity anomalies and disoriented aeromagnetic anomalies are in-line with the mobilistic system revealed by the palaeomagnetic data. These Alpine age continental rotations caused westward wrenching of the global lithosphere and led to significant tectonic reactivation and deformations. GPS measurements, current tectonic knowledge and the results of the evaluation of potential <span class="hlt">field</span> data were combined in a base map to demonstrate similarities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMSM23A2536H&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMSM23A2536H&link_type=ABSTRACT"><span id="translatedtitle">Evolution of auroral acceleration <span class="hlt">region</span> <span class="hlt">field</span>-aligned current systems, plasma, and potentials observed by Cluster during substorms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hull, A. J.; Chaston, C. C.; Fillingim, M. O.; Frey, H. U.; Goldstein, M. L.; Bonnell, J. W.; Mozer, F.</p> <p>2015-12-01</p> <p>The auroral acceleration <span class="hlt">region</span> is an integral link in the chain of events that transpire during substorms, and the currents, plasma and electric <span class="hlt">fields</span> undergo significant changes driven by complex dynamical processes deep in the magnetotail. The acceleration processes that occur therein accelerate and heat the plasma that ultimately leads to some of the most intense global substorm auroral displays. Though this <span class="hlt">region</span> has garnered considerable attention, the temporal evolution of <span class="hlt">field</span>-aligned current systems, associated acceleration processes, and resultant changes in the plasma constituents that occur during key stages of substorm development remain unclear. In this study we present a survey of Cluster traversals within and just above the auroral acceleration <span class="hlt">region</span> (≤3 Re altitude) during substorms. Particular emphasis is on the spatial morphology and developmental sequence of auroral acceleration current systems, potentials and plasma constituents, with the aim of identifying controlling factors, and assessing auroral emmission consequences. Exploiting multi-point measurements from Cluster in combination with auroral imaging, we reveal the injection powered, Alfvenic nature of both the substorm onset and expansion of auroral particle acceleration. We show evidence that indicates substorm onsets are characterized by the gross-intensification and filamentation/striation of pre-existing large-scale current systems to smaller/dispersive scale Alfven waves. Such an evolutionary sequence has been suggested in theoretical models or single spacecraft data, but has not been demonstrated or characterized in multispacecraft observations until now. It is also shown how the Alfvenic variations over time may dissipate to form large-scale inverted-V structures characteristic of the quasi-static aurora. These findings suggest that, in addition to playing active roles in driving substorm aurora, inverted-V and Alfvenic acceleration processes are causally linked. Key</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFMSA43A1888K&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFMSA43A1888K&link_type=ABSTRACT"><span id="translatedtitle">VHF coherent scatter radar observations of mid-latitude F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities over South Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kwak, Y.; Yang, T.; Lee, J.; Hwang, J.; Kil, H.; Park, Y.</p> <p>2011-12-01</p> <p>We examine the mid-latitude F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularity (FAI) activity during 2010-2011 by using the VHF coherent scatter radar data in Daejeon (36.2°N, 127.1°E; dip latitude 26.7°N), South Korea. The VHF radar has been operated since December 2009 and provides a unique opportunity to investigate the variability of the FAI activity with local time, season, solar flux, and magnetic activity. Our preliminary results during the solar minimum show that FAIs preferentially occur at post-sunset and pre-sunrise and during the June solstice. The seasonal variation of the FAI occurrence frequency is similar to that of the electron density irregularities observed by the C/NOFS satellite. For one event, we observed the association of the FAIs with a medium-scale traveling ionospheric disturbance (MSTID). Our study extends to the investigation of the correlations between the irregularities in the equatorial <span class="hlt">region</span> and middle latitudes and between the conjugate F <span class="hlt">regions</span>, and the causal linkage of the FAIs with the E-<span class="hlt">region</span> perturbations. For this purpose, we analyze the VHF radar and C/NOFS data during 2010-2011.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1616962W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1616962W"><span id="translatedtitle">Stochastic models for climate <span class="hlt">field</span> reconstruction over the Euro-Mediterranean <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Werner, Johannes; Toreti, Andrea; Luterbacher, Juerg</p> <p>2014-05-01</p> <p>Over the last decades, several different methods have been used to reconstruct past climatic change. These methods consist of an - often statistical - model and a related inference step. While recently a lot of the discussion has been focused on the latter (Smerdon et al. 2011, Christiansen et al. 2011), the focus on more appropriate models seems promising. In a series of recent pseudoproxy experiments (PPE) for climate <span class="hlt">field</span> reconstructions (Tingley+Huybers 2010a,b; Werner et al. 2013), Bayesian inference was used toghether with a localised stochastic description of the spatio-temporal evolution of annual temperature <span class="hlt">fields</span>. In contrast to other methods that are based on large scale patterns over the full reconstruction domain, the local temporal evolution and spatial dependencies are modelled. The models are based on simple assumptions about the spatio-temporal evolution and have been shown to perform well for temperature reconstructions, at least in pseudo proxy experiments. We show in this contribution how localised climate models can be checked using the Kramers Moyal expansion. We apply this method to estimate models for temperature and precipitation over Europe and the Mediterranean. While such simple models fare well enough for temperatures, precipitation poses new problems. We show that while the model mismatch does indeed introduce errors, it can be neglected when compared to the influence of the proxy data. The effect of noisy proxy time series and spatial sparseness still remains the most prominent source of errors. Smerdon J.E. et al., J Clim 24, 1284-1309 (2011) Tingley M.P. and Huybers P., J Clim 10, 2759-2781, 2782-2800 (2010a,b) Christiansen B. and Ljundqvist F.C., J Clim 24, 6013-6034 (2011) Werner J.P. et al., J Clim 26, 824 (2013)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985JATP...47..945Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985JATP...47..945Z"><span id="translatedtitle">HF scattering induced by <span class="hlt">field</span>-aligned irregularities in the equatorial E-<span class="hlt">region</span> during total solar eclipses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, X. J.; Xiong, N. L.</p> <p>1985-10-01</p> <p>Results and analyses of solar eclipse effects on the lower ionosphere are presented. After the first contact of the total eclipse on February 16, 1980, an absorption increment of 12 dB was observed. At the same time, the frequency of amplitude fading increased and Doppler frequency shift disturbances appeared. The calculation of signal strength is carried out by means of Booker's (1978, 1980) scattering theory, supposing an outer scale equal to 1000 m and an inner scale equal to 5 m, of space scale spectrum of <span class="hlt">field</span>-aligned irregularities in the equatorial E-<span class="hlt">region</span>. The calculated results agree fairly well with observations. Results showed that, because of the formation of lower ionospheric <span class="hlt">field</span>-aligned irregularities in the course of the obscuration of solar local ionization source, radio wave scattering was strengthened.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010GMDD....3..855F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010GMDD....3..855F"><span id="translatedtitle">A pre-processor of trace gases and aerosols emission <span class="hlt">fields</span> for <span class="hlt">regional</span> and global atmospheric chemistry models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Freitas, S. R.; Longo, K. M.; Alonso, M. F.; Pirre, M.; Marecal, V.; Grell, G.; Stockler, R.; Mello, R. F.; Sánchez Gácita, M.</p> <p>2010-06-01</p> <p>The pre-processor PREP-CHEM-SRC presented in the paper is a comprehensive tool aiming at preparing emissions <span class="hlt">fields</span> of trace gases and aerosols for use in <span class="hlt">regional</span> or global transport models. The emissions considered are urban/industrial, biogenic, biomass burning, volcanic, biofuel use and burning from agricultural waste sources from most recent databases or from satellite fire detections for biomass burning. A plumerise model is used to derive the height of smoke emissions from satellite fire products. The pre-processor provides emission <span class="hlt">fields</span> interpolated onto the transport model grid. Several map projections can be chosen. The way to include these emissions in transport models is also detailed. The pre-processor is coded using Fortran 90 and C and is driven by a namelist allowing the user to choose the type of emissions and the database.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989AdSpR...9..377R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989AdSpR...9..377R"><span id="translatedtitle">Plasma wave, magnetic <span class="hlt">field</span> and energetic ion observations in the ion pick-up <span class="hlt">region</span> of Comet Giacobini-Zinner</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, I. G.; Cowley, S. W. H.; Wenzel, K.-P.; Scarf, F. L.; Smith, E. J.; Tsurutani, B. T.; Sanderson, T. R.; Hynds, R. J.</p> <p></p> <p>Simultaneous plasma wave, magnetic <span class="hlt">field</span>, and energetic ion observations made by the ICE spacecraft in the extended ion pick-up <span class="hlt">region</span> surrounding comet Giacobini-Zinner are examined to determine the conditions under which two characteristic wave emissions, electrostatic waves at a few kHz, and electromagnetic waves at a few tens of Hz, are generated. The data are consistent with the view that the kHz electrostatic emissions result from an instability of the pick-up photoelectron 'beam' produced when the angle alpha between the magnetic <span class="hlt">field</span> and the solar wind velocity vector is less than about 60 deg, while the behavior of the tens of Hz electromagnetic waves suggests that they are generated by the pick-up ion 'ring' which is present when alpha exceeds about 60 deg.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740014711','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740014711"><span id="translatedtitle">Parabolic cylinder antennas. [discussed in terms of wave conversions, <span class="hlt">field</span> divergence, and wavefronts in Fresnel and Fraunhofer <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schmidt, R. F.</p> <p>1973-01-01</p> <p>Some of the features of single and dual parabolic-cylinder reflector antenna systems are discussed in terms of wave conversions, <span class="hlt">field</span> divergence, and wavefronts in Fresnel and Fraunhofer <span class="hlt">regions</span>. Beam-squinting, by mechanical displacement and electrical phase gradient methods, is introduced together with the combination of these methods. In the case of dual parabolic cylinders there is also a discussion of surface-truncation, parametric representation of surface intersections, main-aperture blockage by the subsystem, and beam squinting. A few diffraction patterns are presented to illustrate the type of data available via a formulation equivalent to the complex-vector Kirchhoff-Kottler formulation. Main and cross-polarization components of the solution are available as they are inherently part of the <span class="hlt">field</span> solution in the Cartesian coordinate system. A means of displaying main and cross-polarization components for arbitrary beam-scanning in space is outlined. Extensions to monopulse tracking with variable-beamwidth (zooming) capability are introduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1057889','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1057889"><span id="translatedtitle">Exploration of Quench Initiation Due to Intentional Geometrical Defects in a High Magnetic <span class="hlt">Field</span> <span class="hlt">Region</span> of an SRF Cavity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>J. Dai, K. Zhao, G.V. Eremeev, R.L. Geng, A.D. Palczewski; Dai, J.; Palczewski, A. D.; Eremeev, G. V.; Geng, R. L.; Zhao, K.</p> <p>2011-07-01</p> <p>A computer program which was used to simulate and analyze the thermal behaviors of SRF cavities has been developed at Jefferson Lab using C++ code. This code was also used to verify the quench initiation due to geometrical defects in high magnetic <span class="hlt">field</span> <span class="hlt">region</span> of SRF cavities. We built a CEBAF single cell cavity with 4 artificial defects near equator, and this cavity has been tested with T-mapping. The preheating behavior and quench initiation analysis of this cavity will be presented here using the computer program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19950040507&hterms=photoelectric+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2528photoelectric%2Beffect%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19950040507&hterms=photoelectric+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2528photoelectric%2Beffect%2529"><span id="translatedtitle">Photon-dominated <span class="hlt">regions</span> around cool stars: The effects of the color temperature of the radiation <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spaans, Marco; Tielens, A. G. G. M.; Dishoeck, Ewine F. Van; Bakes, E. L. O.</p> <p>1994-01-01</p> <p>We have investigated the influence of the color temperature of the illuminating radiation <span class="hlt">field</span> on the chemical and thermal structure of photon-dominated <span class="hlt">regions</span> (PDRs). We present the results of a study of the photoelectric efficiency of heating by large molecules such as polycyclic aromatic hydrocarbons (PAHs) and very small grains for radiation <span class="hlt">fields</span> characterized by different effective temperatures. We show that the efficiency for cooler (T(sub eff) approximately = 6000-10,000 K) stars is at most an order of magnitude smaller than that for hotter (T(sub eff) approximately = 20,000-30,000 K) stars. While cooler radiation <span class="hlt">fields</span> result in less ultraviolet photons capable of heating, the efficiency per absorbed photon is higher, because the grains become less positively charged. We also present detailed calculations of the chemistry and thermal balance for generic PDRs (n(sub 0) approximately = 10(exp 3), G(sub 0) approximately = 10(exp 3)). For cooler radiation <span class="hlt">fields</span>, the H/H2 and C(+)/C/CO transition layers shift toward the surface of the PDR, because fewer photons are available to photodissociate H2 and CO and to ionize C. The dominant cooling lines are the (C II) 158 micron and the (O I) 63 micron lines for the hotter radiation <span class="hlt">fields</span>, but cooling by CO becomes dominant for a color temperature of 6000 K or lower. The (C II)/CO and (O I)/CO ratios are found to be very good diagnostics for the color temperature of the radiation <span class="hlt">field</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4898144','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4898144"><span id="translatedtitle">Analysis of gene expression in mouse brain <span class="hlt">regions</span> after exposure to 1.9 GHz radiofrequency <span class="hlt">fields</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>McNamee, James P.; Bellier, Pascale V.; Konkle, Anne T. M.; Thomas, Reuben; Wasoontarajaroen, Siriwat; Lemay, Eric; Gajda, Greg B.</p> <p>2016-01-01</p> <p>Abstract Purpose: To assess 1.9 GHz radiofrequency (RF) <span class="hlt">field</span> exposure on gene expression within a variety of discrete mouse brain <span class="hlt">regions</span> using whole genome microarray analysis. Materials and methods: Adult male C57BL/6 mice were exposed to 1.9 GHz pulse-modulated or continuous-wave RF <span class="hlt">fields</span> for 4 h/day for 5 consecutive days at whole body average (WBA) specific absorption rates of 0 (sham), ∼0.2 W/kg and ∼1.4 W/kg. Total RNA was isolated from the auditory cortex, amygdala, caudate, cerebellum, hippocampus, hypothalamus, and medial prefrontal cortex and differential gene expression was assessed using Illumina MouseWG-6 (v2) BeadChip arrays. Validation of potentially responding genes was conducted by RT-PCR. Results: When analysis of gene expression was conducted within individual brain <span class="hlt">regions</span> when controlling the false discovery rate (FDR), no differentially expressed genes were identified relative to the sham control. However, it must be noted that most fold changes among groups were observed to be less than 1.5-fold and this study had limited ability to detect such small changes. While some genes were differentially expressed without correction for multiple-comparisons testing, no consistent pattern of response was observed among different RF-exposure levels or among different RF-modulations. Conclusions: The current study provides the most comprehensive analysis of potential gene expression changes in the rodent brain in response to RF <span class="hlt">field</span> exposure conducted to date. Within the exposure conditions and limitations of this study, no convincing evidence of consistent changes in gene expression was found in response to 1.9 GHz RF <span class="hlt">field</span> exposure. PMID:27028625</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1710378P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1710378P"><span id="translatedtitle">Importance of terrestrial surface density information and satellite-aided global gravity <span class="hlt">field</span> models for high precision <span class="hlt">regional</span> geoid computation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pock, Christian; Mayer-Gürr, Torsten; Rieser, Daniel; Kühtreiber, Norbert</p> <p>2015-04-01</p> <p>High precision <span class="hlt">regional</span> geoid determination is a challenging task. Besides the quality of the input data, the quality of the global gravity <span class="hlt">field</span> data and the density information is essential for a consistent treatment of the gravity <span class="hlt">field</span> quantities within the remove-compute-restore procedure. In this investigation a surface density model based on geological observations is introduced, replacing the constant standard crustal density. The long-wavelength component of the gravity <span class="hlt">field</span> is represented by the GOCO05s global gravity <span class="hlt">field</span> model. The geoid computation is based on a Gauss-Markov model with radial basis function parametrization. The achieved improvements are remarkable and lead to an unprecedented accuracy of the pure gravimetric geoid in Austria. As final outcomes a new geoid solution and a map for the xi and eta components of deflections of the vertical are computed. The achieved results are primarily validated with independent GPS/leveling observations. Secondly validation has been carried out through deflections of the vertical, obtained from precise zenith camera and astronomical measurements. Furthermore, differences between the current official Austrian geoid solution based on data from 2008 and the new estimated geoid are shown. An overview about the achieved improvements and the validation is given in the presentation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.P21A2041C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.P21A2041C"><span id="translatedtitle">The Correlation Between Electron Density and Temperature in Low and High Strength Crustal Magnetic <span class="hlt">Field</span> <span class="hlt">Regions</span> at Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chamandy, T.; Andersson, L.; Fowler, C. M.; Ergun, R.; Connerney, J. E. P.; Brain, D. A.</p> <p>2015-12-01</p> <p>The Langmuir Probe and Waves Instrument (LPW) onboard the MAVEN spacecraft is the first Langmuir probe to map out the upper atmosphere of Mars. The instrument provides measurements (amongst other variables) of electron density (Ne) and temperature (Te). The overarching scientific goal of MAVEN is to determining how Mars lost its atmosphere and to understand the physical processes governing this escape and the above quantities play a crucial role in understanding this. Ne and Te information is critical for determining the efficiency of the different photochemical reaction rates and thereby in understanding the upper atmospheric composition. Understanding the upper atmosphere allows the MAVEN mission to calculate escape rates. Photochemical reactions and collisions dominate below the exobase <span class="hlt">region</span> (~150-~180 km). Above the exobase, particles with energies greater than the Mars gravity well can escape. On the dayside solar EUV heats the atmosphere at lower altitudes and produces the ionosphere. It is of great interest to understand the how the electron density and temperature correlate. The presented study therefore shows the correlation between Ne and Te. This study investigates how different solar zenith angles affect these quantities and evaluates if closed magnetic <span class="hlt">field</span> lines (as expected to occur over crustal magnetic <span class="hlt">fields</span>) change the correlation between the two. Many previous studies have shown that crustal <span class="hlt">fields</span> affect the plasma at high altitudes. In this study we present how the magnetic <span class="hlt">field</span> influences the photochemical and the plasma processes close to the exobase via analyzing Ne and Te.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.5594S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.5594S"><span id="translatedtitle">Storm time equatorial plasma bubble zonal drift reversal due to disturbance Hall electric <span class="hlt">field</span> over the Brazilian <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Santos, A. M.; Abdu, M. A.; Souza, J. R.; Sobral, J. H. A.; Batista, I. S.; Denardini, C. M.</p> <p>2016-06-01</p> <p>The dynamics of equatorial ionospheric plasma bubbles over Brazilian sector during two magnetic storm events are investigated in this work. The observations were made at varying phases of magnetic disturbances when the bubble zonal drift velocity was found to reverse westward from its normally eastward velocity. Calculation of the zonal drift based on a realistic low-latitude ionosphere modeled by the Sheffield University Plasmasphere-Ionosphere Model showed on a quantitative basis a clear competition between vertical Hall electric <span class="hlt">field</span> and disturbance zonal winds on the variations observed in the zonal velocity of the plasma bubble. The Hall electric <span class="hlt">field</span> arising from enhanced ratio of <span class="hlt">field</span> line-integrated conductivities, ΣH/ΣP, is most often generated by an increase in the integrated Hall conductivity, arising from enhanced energetic particle precipitation in the South American Magnetic Anomaly <span class="hlt">region</span> for which evidence is provided from observation of anomalous sporadic E layers over Cachoeira Paulista and Fortaleza. Such sporadic E layers are also by themselves evidence for the development of the Hall electric <span class="hlt">field</span> that modifies the zonal drift.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9459E..0SC','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9459E..0SC"><span id="translatedtitle">Evaluation of VIIRS SST <span class="hlt">fields</span> through the analysis of overlap <span class="hlt">regions</span> between consecutive orbits</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cayula, Jean-François P.; May, Douglas A.; Arnone, Robert A.; Vandermeulen, Ryan A.</p> <p>2015-05-01</p> <p>Full-swath Sea Surface Temperature (SST) derived from data acquired by the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor on-board the Suomi-National Polar-orbiting Partnership (S-NPP) satellite produces significant overlap between consecutive orbits at all latitudes. In this study, we use those overlap <span class="hlt">regions</span> to evaluate VIIRS SST, as inconsistencies between SST values from consecutive orbits are indications of likely degraded quality. The studies investigate two sources of inconsistencies: those resulting from the response of the SST equations when observing a scene from differing view angles and those caused by undetected data contamination. This study will present results for two VIIRS SST products: one from the Naval Oceanographic Office (NAVOCEANO), which is assimilated in the Navy Ocean Models, and the Advanced Clear-Sky Processor for Oceans (ACSPO) product from the National Oceanic and Atmospheric Administration (NOAA) Center for Satellite Applications and Research (STAR). Global statistics based on drifting buoys for both NAVOCEANO and NOAA products complete the analysis.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25377457','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25377457"><span id="translatedtitle">Spectral tuning by opsin coexpression in retinal <span class="hlt">regions</span> that view different parts of the visual <span class="hlt">field</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dalton, Brian E; Loew, Ellis R; Cronin, Thomas W; Carleton, Karen L</p> <p>2014-12-22</p> <p>Vision frequently mediates critical behaviours, and photoreceptors must respond to the light available to accomplish these tasks. Most photoreceptors are thought to contain a single visual pigment, an opsin protein bound to a chromophore, which together determine spectral sensitivity. Mechanisms of spectral tuning include altering the opsin, changing the chromophore and incorporating pre-receptor filtering. A few exceptions to the use of a single visual pigment have been documented in which a single mature photoreceptor coexpresses opsins that form spectrally distinct visual pigments, and in these exceptions the functional significance of coexpression is unclear. Here we document for the first time photoreceptors coexpressing spectrally distinct opsin genes in a manner that tunes sensitivity to the light environment. Photoreceptors of the cichlid fish, Metriaclima zebra, mix different pairs of opsins in retinal <span class="hlt">regions</span> that view distinct backgrounds. The mixing of visual pigments increases absorbance of the corresponding background, potentially aiding the detection of dark objects. Thus, opsin coexpression may be a novel mechanism of spectral tuning that could be useful for detecting prey, predators and mates. However, our calculations show that coexpression of some opsins can hinder colour discrimination, creating a trade-off between visual functions. PMID:25377457</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.B53B1197G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.B53B1197G"><span id="translatedtitle">Remote Estimation of Gross Primary Production in Crops at <span class="hlt">Field</span> and <span class="hlt">Regional</span> Levels</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gitelson, A. A.; Vina, A.; Verma, S. B.; Rundquist, D. C.</p> <p>2007-12-01</p> <p>Accurate estimation of spatially distributed CO2 fluxes is of great importance for <span class="hlt">regional</span> and global studies of carbon balance. We have found that in irrigated and rainfed crops (maize and soybean), GPP is closely related to total crop chlorophyll content. The finding allowed development of a new technique for remote estimation of crop chlorophyll specifically for assessing gross primary production. The technique is based on reflectance in two spectral channels: the near-infrared and either the green or the red-edge. The technique provided accurate estimations of daily GPP in both crops. Validation using independent datasets for irrigated and rainfed maize and soybean documented the robustness of the technique. We report also about applying the developed technique for GPP retrieval from data acquired by both an airborne imaging spectrometer (AISA-Eagle) and Landsat ETM+. The Chlorophyll Index, retrieved from Landsat ETM+ data, was found to be an accurate surrogate measure for daily crop GPP with a root mean square error of GPP prediction of less than 1.58 g C m-2d-1 in a GPP range of 1.88 g C m-2d-1 to 23.1 g C m-2d-1. These results suggest new possibilities for analyzing the spatio-temporal variation of the GPP of crops using not only the extensive archive of Landsat Thematic Mapper imagery acquired since the early 1980s but also the 500-m/pixel data currently being acquired by MODIS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011amos.confE..51D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011amos.confE..51D"><span id="translatedtitle">Innovative system of very wide <span class="hlt">field</span> optical sensors for space surveillance in the LEO <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dimare, L.; Farnocchia, D.; Gronchi, G.; Milani, A.; Bernardi, F.; Rossi, A.</p> <p>2011-09-01</p> <p>We present the results of a large scale simulation, reproducing the behavior of a data center for the build-up and maintenance of a complete catalog of space debris in the upper part of the low Earth orbits <span class="hlt">region</span> (LEO). The purpose is to determine the achievable performances of a network of advanced optical sensors, through the use of the newest orbit determination algorithms developed by the Department of Mathematics of Pisa (DM). Such a network was designed and proposed to the European Space Agency (ESA) in the Space Situational Awareness (SSA) framework by Carlo Gavazzi Space SpA (CGS), Istituto Nazionale di Astrofisica (INAF), DM and Istituto di Scienza e Tecnologie dell'Informazione (ISTI-CNR). The latest developed orbit determination algorithms were used to process simulated observations from the proposed network. In particular two innovative methods for preliminary orbit determination based on the first integrals of the Kepler problem were compared, by using them to process the same data. In both cases, the results showed that it is possible to use a network of optical sensors to build up a catalog containing more than 98% of the objects with perigee height between 1100 and 2000 km, and diameter greater than 8 cm. Such a catalog is obtained in just two months of observations. However, such results depend upon specific assumptions on the sensor and on the software technologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4240992','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4240992"><span id="translatedtitle">Spectral tuning by opsin coexpression in retinal <span class="hlt">regions</span> that view different parts of the visual <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dalton, Brian E.; Loew, Ellis R.; Cronin, Thomas W.; Carleton, Karen L.</p> <p>2014-01-01</p> <p>Vision frequently mediates critical behaviours, and photoreceptors must respond to the light available to accomplish these tasks. Most photoreceptors are thought to contain a single visual pigment, an opsin protein bound to a chromophore, which together determine spectral sensitivity. Mechanisms of spectral tuning include altering the opsin, changing the chromophore and incorporating pre-receptor filtering. A few exceptions to the use of a single visual pigment have been documented in which a single mature photoreceptor coexpresses opsins that form spectrally distinct visual pigments, and in these exceptions the functional significance of coexpression is unclear. Here we document for the first time photoreceptors coexpressing spectrally distinct opsin genes in a manner that tunes sensitivity to the light environment. Photoreceptors of the cichlid fish, Metriaclima zebra, mix different pairs of opsins in retinal <span class="hlt">regions</span> that view distinct backgrounds. The mixing of visual pigments increases absorbance of the corresponding background, potentially aiding the detection of dark objects. Thus, opsin coexpression may be a novel mechanism of spectral tuning that could be useful for detecting prey, predators and mates. However, our calculations show that coexpression of some opsins can hinder colour discrimination, creating a trade-off between visual functions. PMID:25377457</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JaJAP..52dCC23S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JaJAP..52dCC23S"><span id="translatedtitle">1/f Noise Characteristics of Fin-Type <span class="hlt">Field</span>-Effect Transistors in Saturation <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakai, Hideo; O'uchi, Shin-ichi; Endo, Kazuhiko; Matsukawa, Takashi; Liu, Yongxun; Ishikawa, Yuki; Tsukada, Junichi; Nakagawa, Tadashi; Sekigawa, Toshihiro; Koike, Hanpei; Masahara, Meishoku; Ishikuro, Hiroki</p> <p>2013-04-01</p> <p>In this work, we measured 1/f noise of independent-double-gate- (IDG-) fin-type FET (FinFET) which has two independent gates. Flicker noise of common-double-gate- (CDG-) mode which both gates are applied with the same voltage and IDG-mode that has one gate voltage grounded and the other gate voltage applied with arbitrary voltage, and both result were compared with the same drain current (Id). First, we measured relationship between characteristic of the normalized 1/f noise by Id (SId /Id2) and characteristic of Id. Both the SId /Id2 of IDG- and CDG-modes show nearly equal values and tendency. Next, this work also shows the relationship between 1/f noise and vertical electric <span class="hlt">field</span> (E⊥) of surface of gate oxide film. As a result we could not definitely see a large margin of 1/f noise between CDG- and IDG-modes from E⊥. This work also discovered that 1/f noise was greatly influenced by Id density.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3712407','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3712407"><span id="translatedtitle">Oral rehydration solutions for burn management in the <span class="hlt">field</span> and underdeveloped <span class="hlt">regions</span>: a review</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Vyas, Krishna S; Wong, Lesley K</p> <p>2013-01-01</p> <p>Burn injuries are the fourth most common type of trauma worldwide, and the appropriate care of burn injuries in resource-limited settings such as the battlefield, underdeveloped nations, or in mass casualtiesremains a significant challenge. Rehydration constitutes the primary treatment of the systemic effects of burns and is a major factor in patient recovery. The standard of care for the replenishment of fluid and electrolyte losses in burn injury remains intravenous fluid therapy, but oral rehydration solution therapy (ORST) demonstrates beneficial utility in saving the lives of burn patients when they are applied in the acute phase of burn injuries, especially when intravenous rehydration is unavailable or inaccessible. Advantages of ORST as compared to intravenous therapy include availability, ease of administration in the <span class="hlt">field</span>, low risk of infections and complications, low cost, and no requirement for accessory or specialized equipment. These benefits position ORST very attractively for the provision of interim first aid until definitive medical assistance arrives. Extensive and comprehensive investigation may be warranted to elucidate, account for and quantify individual burn patient biochemical variables toward the potential realization of such an “omniuse” oral rehydration solution for the benefit of burn injuries worldwide. PMID:23875118</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26213234','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26213234"><span id="translatedtitle">Investigating Alfvénic wave propagation in coronal open-<span class="hlt">field</span> <span class="hlt">regions</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Morton, R J; Tomczyk, S; Pinto, R</p> <p>2015-01-01</p> <p>The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves. The existence of Alfvén waves far from the Sun has been known since the 1970s, and recently the presence of ubiquitous Alfvénic waves throughout the solar atmosphere has been confirmed. However, the presence of atmospheric Alfvénic waves does not, alone, provide sufficient support for wave-based models; the existence of counter-propagating Alfvénic waves is crucial for the development of turbulence. Here, we demonstrate that counter-propagating Alfvénic waves exist in open coronal magnetic <span class="hlt">fields</span> and reveal key observational insights into the details of their generation, reflection in the upper atmosphere and outward propagation into the solar wind. The results enhance our knowledge of Alfvénic wave propagation in the solar atmosphere, providing support and constraints for some of the recent Alfvén wave turbulence models. PMID:26213234</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/127633','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/127633"><span id="translatedtitle"><span class="hlt">Regional</span> implications of the Bashkerian-Serpukhovian reservoir architecture at Tengiz <span class="hlt">field</span>; Kazakhstan</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lomando, A.J.; Suisenov, K.; Shilin, A.</p> <p>1995-08-01</p> <p>The super-giant Tengiz <span class="hlt">Field</span> is a complex Carboniferous-Devonian reservoir. The most common occurrence of higher porosity zones is in the uppermost portion of the reservoir within the Bashkerian to Serpukhovian section. The suite of porous textures containing preserved primary porosity ranges from skeletal and coated grain to mixed particle grainstones, and packstones which display little or no compaction due to early isopachous marine cementation. In some areas, the amount of primary preserved porosity is inversely proportional to th occurrence and amount of crinoids and associated syntaxial overgrowths. Early and late secondary porosity is most pronounced in the upper portions of the reservoir associated with features ranging from multiple short-term exposure events to long-duration unconformities. Lower energy wackestones and mudstones interbedded with higher energy facies cause verticle permeability barriers and baffles. In areas of stacked shoaling cycles in the platform interior, lateral correlation of porosity zones is good. Muddy biolithites tend to be concentrated along the north and eastern portions of the structure and generally contain lower reservoir quality and cause lateral changes in reservoir continuity. Preliminary analysis of facies distribution patterns indicates that the higher energy {open_quotes}windward{close_quotes} direction is not facing into the North Caspian basin, but to the east-northeast into the Emba sub-basin. This allows for a separate exploration play concept around the Emba sub-basin {open_quotes}rim{close_quotes} which would be separate and distinct from the rest of the North Caspian Basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5802595','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5802595"><span id="translatedtitle">Structure of pre-Caspian depression and major oil and gas <span class="hlt">fields</span> of the <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Krylov, N.A. ); Avrov, V.P. ); Lisovsky, N.N.</p> <p>1991-03-01</p> <p>As a single unified depression, the pre-Caspian basin has been formed from Paleozoic to Cenozoic time. The basin is superimposed on two large pre-Permian depressions. On the Astrakhan-Aktyubinsk zone of uplifts between them is found sharply reduced Carboniferous and Devonian sections. Modern structural plan clearly displays two major structural stages: Subsalt (Paleozoic) and post (post-Kungurian). The post-salt stage is characterized by wide development of salt dome tectonics. It corresponds with its own petroliferous stage containing numerous, mostly small oil accumulations in terrigenous Mesozoic reservoirs. Large recent discoveries-Astrakhan condensate, Karachaganak and Kanazhol-Sinelnikov oil/condensate, Tengiz oil, and other <span class="hlt">fields</span>-are associated with the Subsalt Paleozoic complex ranging from Lower Permian to the top of Upper Devonian. The Subsalt stage has its own regularities in hydrocarbon phase differentiation; large reserves concentration; dominantly productive carbonates with various reservoirs; and presence of structural, depositional, and erosional factors controlling formation of oil and gas traps. The paper describes major distributional features of the various arc-and-type Permian and Carboniferous formations, which in conjunction with Subsalt paleotemperature data and geochemistry of organic matter represents a basis for the forecast of new discoveries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1043116','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1043116"><span id="translatedtitle">Impact of E4 Training and <span class="hlt">Field</span> Auditing of GSA Heartland <span class="hlt">Region</span> Facilities</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fernandez, Nicholas; Gowri, Krishnan; Underhill, Ronald M.; Goddard, James K.</p> <p>2012-04-01</p> <p>To assess the impact of energy efficiency expert evaluation (E4) training and <span class="hlt">field</span> audits performed since 2007, the Federal Energy Management Program (FEMP) undertook a follow-up study on the implementation of E4 recommendations and an analysis of energy savings. The building property manager and O and M contractor of each facility were interviewed to obtain feedback and implementation status of the E4 recommendations. Overall, there were more than 160 recommendations documented in the E4 reports; about 50% of these recommendations were fully implemented and the remaining 50% either partially implemented or not implemented. In four buildings, the E4 recommendations were aligned with American Recovery and Reinvestment Act of 2009 (ARRA) projects replacing HVAC equipment or upgrading the building control system. The E4 recommendations were not followed-up in two buildings because of uncertainty of the long-term use of the facility or personnel changes. Results of this followon study are reported in this document.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4525157','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4525157"><span id="translatedtitle">Investigating Alfvénic wave propagation in coronal open-<span class="hlt">field</span> <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Morton, R. J.; Tomczyk, S.; Pinto, R.</p> <p>2015-01-01</p> <p>The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves. The existence of Alfvén waves far from the Sun has been known since the 1970s, and recently the presence of ubiquitous Alfvénic waves throughout the solar atmosphere has been confirmed. However, the presence of atmospheric Alfvénic waves does not, alone, provide sufficient support for wave-based models; the existence of counter-propagating Alfvénic waves is crucial for the development of turbulence. Here, we demonstrate that counter-propagating Alfvénic waves exist in open coronal magnetic <span class="hlt">fields</span> and reveal key observational insights into the details of their generation, reflection in the upper atmosphere and outward propagation into the solar wind. The results enhance our knowledge of Alfvénic wave propagation in the solar atmosphere, providing support and constraints for some of the recent Alfvén wave turbulence models. PMID:26213234</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.H53F1114D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.H53F1114D"><span id="translatedtitle">Water Quality in an Elevated CO2 <span class="hlt">Region</span>: a <span class="hlt">Field</span> Study at Mammoth Lakes, CA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dwyer, C. D.; Ellis, A. S.; Khachikian, C.; CenterEnergy; Sustainability</p> <p>2010-12-01</p> <p>Increasing levels of anthropogenic carbon dioxide in the atmosphere have led to concern with regard to the consequences of global warming. Efforts to limit, if not prevent, further increases are becoming a great priority. Among the variety of proposed mitigation methods is that of injecting CO2 into structural reservoirs in deep permeable geologic formations. Understanding the potential side effects on the environment should leaks occur is essential to our ability to prepare and mitigate environmental hazards. This study examines the effect of elevated soil levels of CO2 on water chemistry. In more specific terms, the purpose is to find geochemical signatures to indicate that elevated CO2 is causing observable changes in water chemistry. Preliminary targets elements are Si, Al and Sr in conjunction with major ions. Mammoth Mountain provides an excellent study area as CO2 gas from an underlying magma chamber has been leaking into the overlying soil, turning it into a natural analogue to a leaking CO2 storage formation. Accelerated weathering of minerals is hypothesized to occur in concert with elevated CO2 levels. Water samples were collected from Horseshoe Lake (adjacent to a high flux of soil CO2), streams that drain into Horseshoe lake, and from Mcleod Lake (with “normal” CO2 levels). Preliminary results show that the waters of Mammoth Lakes are generally dilute, with the major inputs being snowmelt and runoff from Mammoth Mountain. Water samples from the high CO2 Horseshoe Lake area have higher alkalinity (0.295 meq/L compared to 0.047 meq/L at McLeod Lake), an indication of more weathering occurring at the high CO2 lake. Weathering from alumnosilicate minerals is one of the main sources of dissolved ions to waters in the <span class="hlt">region</span>. Al and Si concentrations are higher in the streams (39μg/L and 4575μg/L respectively) than in the lake (16μg/L and 3074 respectively). Al/Na molar ratios in Horseshoe Lake range from 0.008 - 0.028 while stream inputs to the lake</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PApGe.162.1367Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PApGe.162.1367Z"><span id="translatedtitle">Preliminary Analysis of Observations on the Ultra-Low Frequency Electric <span class="hlt">Field</span> in the Beijing <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhuang, Jiancang; Vere-Jones, David; Guan, Huaping; Ogata, Yosihiko; Ma, Li</p> <p>2005-06-01</p> <p>This paper presents a preliminary analysis of observations on ultra-low frequency ground electric signals from stations operated by the China Seismological Bureau over the last 20 years. A brief description of the instrumentation, operating procedures and data processing procedures is given. The data analyzed consists of estimates of the total strengths (cumulated amplitudes) of the electric signals during 24-hour periods. The thresholds are set low enough so that on most days a zero observation is returned. Non-zero observations are related to electric and magnetic storms, occasional man-made electrical effects, and, apparently, some pre-, co-, or postseismic signals. The main purpose of the analysis is to investigate the extent that the electric signals can be considered as preseismic in character. For this purpose the electric signals from each of five stations are jointly analyzed with the catalogue of local earthquakes within circular <span class="hlt">regions</span> around the selected stations. A version of Ogata’s Lin-Lin algorithm is used to estimate and test the existence of a pre-seismic signal. This model allows the effect of the electric signals to be tested, even after allowing for the effects of earthquake clustering. It is found that, although the largest single effect influencing earthquake occurrence is the clustering tendency, there remains a significant preseismic component from the electrical signals. Additional tests show that the apparent effect is not postseismic in character, and persists even under variations of the model and the time periods used in the analysis. Samples of the data are presented and the full data sets have been made available on local websites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70022072','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70022072"><span id="translatedtitle">Quantification and <span class="hlt">regionalization</span> of groundwater recharge in South-Central Kansas: Integrating <span class="hlt">field</span> characterization, statistical analysis, and GIS</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Sophocleous, M.</p> <p>2000-01-01</p> <p>A practical methodology for recharge characterization was developed based on several years of <span class="hlt">field</span>-oriented research at 10 sites in the Great Bend Prairie of south-central Kansas. This methodology combines the soil-water budget on a storm-by-storm year-round basis with the resulting watertable rises. The estimated 1985-1992 average annual recharge was less than 50mm/year with a range from 15 mm/year (during the 1998 drought) to 178 mm/year (during the 1993 flood year). Most of this recharge occurs during the spring months. To <span class="hlt">regionalize</span> these site-specific estimates, an additional methodology based on multiple (forward) regression analysis combined with classification and GIS overlay analyses was developed and implemented. The multiple regression analysis showed that the most influential variables were, in order of decreasing importance, total annual precipitation, average maximum springtime soil-profile water storage, average shallowest springtime depth to watertable, and average springtime precipitation rate. Therefore, four GIS (ARC/INFO) data "layers" or coverages were constructed for the study <span class="hlt">region</span> based on these four variables, and each such coverage was classified into the same number of data classes to avoid biasing the results. The normalized regression coefficients were employed to weigh the class rankings of each recharge-affecting variable. This approach resulted in recharge zonations that agreed well with the site recharge estimates. During the "Great Flood of 1993," when rainfall totals exceeded normal levels by -200% in the northern portion of the study <span class="hlt">region</span>, the developed <span class="hlt">regionalization</span> methodology was tested against such extreme conditions, and proved to be both practical, based on readily available or easily measurable data, and robust. It was concluded that the combination of multiple regression and GIS overlay analyses is a powerful and practical approach to <span class="hlt">regionalizing</span> small samples of recharge estimates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22032945','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22032945"><span id="translatedtitle"><span class="hlt">Regional</span> electric <span class="hlt">field</span> induced by electroconvulsive therapy in a realistic finite element head model: influence of white matter anisotropic conductivity.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Won Hee; Deng, Zhi-De; Kim, Tae-Seong; Laine, Andrew F; Lisanby, Sarah H; Peterchev, Angel V</p> <p>2012-02-01</p> <p>We present the first computational study investigating the electric <span class="hlt">field</span> (E-<span class="hlt">field</span>) strength generated by various electroconvulsive therapy (ECT) electrode configurations in specific brain <span class="hlt">regions</span> of interest (ROIs) that have putative roles in the therapeutic action and/or adverse side effects of ECT. This study also characterizes the impact of the white matter (WM) conductivity anisotropy on the E-<span class="hlt">field</span> distribution. A finite element head model incorporating tissue heterogeneity and WM anisotropic conductivity was constructed based on structural magnetic resonance imaging (MRI) and diffusion tensor MRI data. We computed the spatial E-<span class="hlt">field</span> distributions generated by three standard ECT electrode placements including bilateral (BL), bifrontal (BF), and right unilateral (RUL) and an investigational electrode configuration for focal electrically administered seizure therapy (FEAST). The key results are that (1) the median E-<span class="hlt">field</span> strength over the whole brain is 3.9, 1.5, 2.3, and 2.6 V/cm for the BL, BF, RUL, and FEAST electrode configurations, respectively, which coupled with the broad spread of the BL E-<span class="hlt">field</span> suggests a biophysical basis for observations of superior efficacy of BL ECT compared to BF and RUL ECT; (2) in the hippocampi, BL ECT produces a median E-<span class="hlt">field</span> of 4.8 V/cm that is 1.5-2.8 times stronger than that for the other electrode configurations, consistent with the more pronounced amnestic effects of BL ECT; and (3) neglecting the WM conductivity anisotropy results in E-<span class="hlt">field</span> strength error up to 18% overall and up to 39% in specific ROIs, motivating the inclusion of the WM conductivity anisotropy in accurate head models. This computational study demonstrates how the realistic finite element head model incorporating tissue conductivity anisotropy provides quantitative insight into the biophysics of ECT, which may shed light on the differential clinical outcomes seen with various forms of ECT, and may guide the development of novel stimulation paradigms</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22092373','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22092373"><span id="translatedtitle">ABRUPT CHANGES OF THE PHOTOSPHERIC MAGNETIC <span class="hlt">FIELD</span> IN ACTIVE <span class="hlt">REGIONS</span> AND THE IMPULSIVE PHASE OF SOLAR FLARES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cliver, E. W.; Petrie, G. J. D.; Ling, A. G.</p> <p>2012-09-10</p> <p>We compared time profiles of changes of the unsigned photospheric magnetic flux in active <span class="hlt">regions</span> with those of their associated soft X-ray (SXR) bursts for a sample of 75 {>=} M5 flares well observed by Global Oscillation Network Group longitudinal magnetographs. Sixty-six of these events had stepwise changes in the spatially integrated unsigned flux during the SXR flares. In superposed epoch plots for these 66 events, there is a sharp increase in the unsigned magnetic flux coincident with the onset of the flare impulsive phase while the end of the stepwise change corresponds to the time of peak SXR emission. We substantiated this result with a histogram-based comparison of the timing of flux steps (onset, midpoint of step, and end) for representative points in the flaring <span class="hlt">regions</span> with their associated SXR event time markers (flare onset, onset of impulsive phase, time of peak logarithmic derivative, maximum). On an individual event basis, the principal part of the stepwise magnetic flux change occurred during the main rise phase of the SXR burst (impulsive phase onset to SXR peak) for {approx}60% of the 66 cases. We find a close timing agreement between magnetic flux steps and >100 keV emission for the three largest hard X-ray (>100 keV) bursts in our sample. These results identify the abrupt changes in photospheric magnetic <span class="hlt">fields</span> as an impulsive phase phenomenon and indicate that the coronal magnetic <span class="hlt">field</span> changes that drive flares are rapidly transmitted to the photosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5982A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5982A"><span id="translatedtitle">Monitoring of flood irrigation for the characterization of irrigation practices of grassland <span class="hlt">fields</span> in the Crau <span class="hlt">region</span> (South of France)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alkassem Alosman, Mohamed; Ruy, Stéphane; Olioso, Albert; Flamain, Fabrice</p> <p>2015-04-01</p> <p>Surface irrigation (flooding and furrow) is the main irrigation technic in the world. This irrigation system is known as having poor water efficiency and that results in very large water losses through drainage and runoff out the <span class="hlt">field</span>. Although these unused water amounts can generate positive externalities (wetlands and groundwater recharge), a decreased of water volume used in surface irrigation is sought in a context of limited water resource. In the Crau area (South of France), more than 12,500 ha of grassland are irrigated by flooding. There, at the <span class="hlt">regional</span> scale, it is estimated that the water volumes brought into the <span class="hlt">field</span> are very high; and ranges from 15,000; up to 20,000 m3.h-1.year-1; more than 78% of these amounts recharges the Crau aquifer (Saos, 2006). However, the actual volumes which are injected to the plot surface (the " irrigation dose ") are insufficiently known, because of the diversity of encountered agricultural practices and <span class="hlt">fields</span> topography. For better characterizing these practices, a campaign of irrigation monitoring has been carried out during an irrigation season (March to September 2014) on a set of representative plots of soil variability, practices, and different stages of hay grow. Each grassland <span class="hlt">field</span> has been also characterized from a topographical and pedological view point. A mobile device for measurements (soil moisture and water level probes, photographic monitoring, soil sampling, .. ) was deployed for each irrigation. A total of 35 irrigation events were followed. The data obtained allow describing accurately and quantitatively the variability in encountered irrigation practices. Combined with a flood irrigation model (Model CALHY, Bader et al., 2010, Hydrol. Sci. J., 55, 177-191), these data will be used to calculate the water balance at the <span class="hlt">field</span> scale: amounts of injected, infiltrated and lost water by runoff or drainage. They will also offer different ways for optimizing the irrigation efficiency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014EGUGA..1616784M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014EGUGA..1616784M&link_type=ABSTRACT"><span id="translatedtitle">CO2 Fluxes Monitoring at the Level of <span class="hlt">Field</span> Agroecosystem in Moscow <span class="hlt">Region</span> of Russia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meshalkina, Joulia; Mazirov, Ilya; Samardzic, Miljan; Yaroslavtsev, Alexis; Valentini, Riccardo; Vasenev, Ivan</p> <p>2014-05-01</p> <p>The Central Russia is still one of the less GHG-investigated European areas especially in case of agroecosystem-level carbon dioxide fluxes monitoring by eddy covariance method. The eddy covariance technique is a statistical method to measure and calculate vertical turbulent fluxes within atmospheric boundary layers. The major assumption of the metod is that measurements at a point can represent an entire upwind area. Eddy covariance researches, which could be considered as repeated for the same area, are very rare. The research has been carried out on the Precision Farming Experimental <span class="hlt">Field</span> of the Russian Timiryazev State Agricultural University (Moscow, Russia) in 2013 under the support of RF Government grant No. 11.G34.31.0079. Arable derno-podzoluvisls have around 1 The results have shown high daily and seasonal dynamic of agroecosystem CO2 emission. Sowing activates soil microbiological activity and the average soil CO2 emission and adsorption are rising at the same time. CO2 streams are intensified after crop emerging from values of 3 to 7 μmol/s-m2 for emission, and from values of 5 to 20 μmol/s-m2 for adsorption. Stabilization of the flow has come at achieving plants height of 10-12 cm. The vegetation period is characterized by high average soil CO2 emission and adsorption at the same time, but the adsorption is significantly higher. The resulted CO2 absorption during the day is approximately 2-5 times higher than emissions at night. For example, in mid-June, the absorption value was about 0.45 mol/m2 during the day-time, and the emission value was about 0.1 mol/m2 at night. After harvesting CO2 emission is becoming essentially higher than adsorption. Autumn and winter data are fluctuate around zero, but for some periods a small predominance of CO2 emissions over the absorption may be observed. The daily dynamics of CO2 emissions depends on the air temperature with the correlation coefficient changes between 0.4 and 0.8. Crop stage, agrotechnological</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016ApJ...826..209Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016ApJ...826..209Y&link_type=ABSTRACT"><span id="translatedtitle">IRX-β Relation of Star-forming <span class="hlt">Regions</span> in NGC 628 Based on Integral <span class="hlt">Field</span> Spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ye, Chengyun; Zou, Hu; Lin, Lin; Lian, Jianhui; Hu, Ning; Kong, Xu</p> <p>2016-08-01</p> <p>It has been found that the infrared-to-ultraviolet luminosity ratio (IRX) and ultraviolet spectral slope (β) have a tight correlation in starburst galaxies, while in normal galaxies the relation is deviated and has a much larger scatter. Star formation <span class="hlt">regions</span> are much simpler in both morphology and physical properties than galaxies, so their photometric and spectroscopic properties are more easily and accurately determined. We have used the integral <span class="hlt">field</span> spectroscopy and multiband photometric images to study the IRX–β relation of H ii <span class="hlt">regions</span> in a nearby galaxy, NGC 628. There are obvious correlations between the Dn (4000), stellar population age, star formation rate, especially Hα equivalent width EW(Hα), and deviation distance d p from the starburst IRX–β relation. However, there is little correlation between the Balmer decrement, metallicity, and d p. It is much more complicated than expected, so that we cannot introduce a single second parameter to describe the scatter and deviation of the H ii <span class="hlt">region</span> IRX–β relation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012IEITE..95..820K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012IEITE..95..820K"><span id="translatedtitle">Study on Threshold Voltage Control of Tunnel <span class="hlt">Field</span>-Effect Transistors Using VT-Control Doping <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Hyungjin; Sun, Min-Chul; Kim, Hyun Woo; Kim, Sang Wan; Kim, Garam; Park, Byung-Gook</p> <p></p> <p>Although the Tunnel <span class="hlt">Field</span>-Effect Transistor (TFET) is a promising device for ultra-low power CMOS technology due to the ability to reduce power supply voltage and very small off-current, there have been few reports on the control of VT for TFETs. Unfortunately, the TFET needs a different technique to adjust VT than the MOSFET by channel doping because most of TFETs are fabricated on SOI substrates. In this paper, we propose a technique to control VT of the TFET by putting an additional VT-control doping <span class="hlt">region</span> (VDR) between source and channel. We examine how much VT is changed by doping concentration of VDR. The change of doping concentration modulates VT because it changes the semiconductor work function difference, φs,channel-φs,source, at off-state. Also, the effect of the size of VDR is investigated. The <span class="hlt">region</span> can be confined to the silicon surface because most of tunneling occurs at the surface. At the same time, we study the optimum width of this <span class="hlt">region</span> while considering the mobility degradation by doping. Finally, the effect of the SOI thickness on the VDR adjusted VT of TFET is also investigated.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004JASTP..66.1615P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004JASTP..66.1615P"><span id="translatedtitle">Statistical characteristics of VHF radar observations of low latitude E-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities over Gadanki</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patra, A. K.; Sripathi, S.; Sivakumar, V.; Rao, P. B.</p> <p>2004-11-01</p> <p>The statistical characteristics of E-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities observed with the Gadanki MST radar are presented and compared with observations made with the Piura radar at a similar magnetic latitude. Echoes are observed day and night, with the nighttime echoes being more intense and covering a greater height extent than during the day. The most probable echo occurrence times are just after sunrise (95%) and just before sunset (80%), when the echoing <span class="hlt">regions</span> were centered around 95 and 100 km, respectively. The lowest probability of echo occurrence is found to be during noontime hours. The spectra of these echoes over Gadanki were all type 2. The mean Doppler velocities for altitudes above 105 km were upward at typically 10ms-1 during the day and downward at about 10ms-1 during the night. Spectral widths of 10-40ms-1 were found during the day and 30-60ms-1 during the night. These characteristics of E-<span class="hlt">region</span> irregularities over Gadanki are quite similar to those found over Piura, and are remarkably different from those at either equatorial or higher latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008GeoRL..35.2402A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008GeoRL..35.2402A"><span id="translatedtitle">Utility of thermal image sharpening for monitoring <span class="hlt">field</span>-scale evapotranspiration over rainfed and irrigated agricultural <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Agam, Nurit; Kustas, William P.; Anderson, Martha C.; Li, Fuqin; Colaizzi, Paul D.</p> <p>2008-01-01</p> <p>The utility of a thermal image sharpening algorithm (TsHARP) in providing fine resolution land surface temperature data to a Two-Source-Model for mapping evapotranspiration (ET) was examined over two agricultural <span class="hlt">regions</span> in the U.S. One site is in a rainfed corn and soybean production <span class="hlt">region</span> in central Iowa. The other lies within the Texas High Plains, an irrigated agricultural area. It is concluded that in the absence of fine (sub-<span class="hlt">field</span> scale) resolution thermal data, TsHARP provides an important tool for monitoring ET over rainfed agricultural areas. In contrast, over irrigated <span class="hlt">regions</span>, TsHARP applied to kilometer-resolution thermal imagery is unable to provide accurate fine resolution land surface temperature due to significant sub-pixel moisture variations that are not captured in the sharpening procedure. Consequently, reliable estimation of ET and crop stress requires thermal imagery acquired at high spatial resolution, resolving the dominant length-scales of moisture variability present within the landscape.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22340187','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22340187"><span id="translatedtitle">A DEEP CHANDRA OBSERVATION OF THE GIANT H II <span class="hlt">REGION</span> N11. I. X-RAY SOURCES IN THE <span class="hlt">FIELD</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Nazé, Yaël; Wang, Q. Daniel; Chu, You-Hua; Gruendl, Robert; Oskinova, Lida</p> <p>2014-08-01</p> <p>A very sensitive X-ray investigation of the giant H II <span class="hlt">region</span> N11 in the Large Megallanic Cloud was performed using the Chandra X-ray Observatory. The 300 ks observation reveals X-ray sources with luminosities down to 10{sup 32} erg s{sup –1}, increasing the number of known point sources in the <span class="hlt">field</span> by more than a factor of five. Among these detections are 13 massive stars (3 compact groups of massive stars, 9 O stars, and one early B star) with log (L {sub X}/L {sub BOL}) ∼–6.5 to –7, which may suggest that they are highly magnetic or colliding-wind systems. On the other hand, the stacked signal for <span class="hlt">regions</span> corresponding to undetected O stars yields log (L {sub X}/L {sub BOL}) ∼–7.3, i.e., an emission level comparable to similar Galactic stars despite the lower metallicity. Other point sources coincide with 11 foreground stars, 6 late-B/A stars in N11, and many background objects. This observation also uncovers the extent and detailed spatial properties of the soft, diffuse emission <span class="hlt">regions</span>, but the presence of some hotter plasma in their spectra suggests contamination by the unresolved stellar population.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18..627C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18..627C"><span id="translatedtitle">Monitoring soil erosion in terraced catchments in Mediterranean <span class="hlt">regions</span>: a <span class="hlt">field</span> experiment in Cyprus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Camera, Corrado; Djuma, Hakan; Zoumides, Christos; Eliades, Marinos; Bruggeman, Adriana; Abate, Dante; Faka, Marina; Hermon, Sorin</p> <p>2016-04-01</p> <p>Terraces retained by dry-stone walls are very common features in mountainous Mediterranean environments. These structures provide accessible agricultural land on steep slopes, favoring water infiltration and reducing water runoff and soil erosion. However, during the last decades, an increasing trend of agricultural land abandonment has resulted in a lack of maintenance of the terrace walls and the onset of a general process of land degradation. The objective of this study is the quantification of soil erosion in a small terraced catchment (10,000 m2), located on the north-eastern slope of the Troodos Mountains (Cyprus), at an elevation of 1,300 m a.s.l. The catchment is cultivated with vineyards and it is representative of the main agricultural land use in the Troodos <span class="hlt">region</span>. Soil erosion is measured by sediment traps and laser scans are made to assess changes in terrace geometry. In addition, a weather station measuring rainfall, temperature and relative humidity has been installed in the catchment, along with 18 soil moisture sensors, to relate soil erosion processes with climate and (sub)surface hydrology. A total of 10 sediment traps, five pairs, have been installed in the study site, catching five well-maintained sections of a dry-stone wall and five degraded (collapsed) sections. Each trap is 1 m wide. In detail, two terraces, 11 and 14 m long, located at the same elevation and separated by a strip of natural vegetation, are monitored with four and six traps, respectively. To get a complete picture of the erosion processes occurring on the selected area, the trap pairs collect sediment from both the collapsed and the well maintained wall sections of the two terraces. In addition, terrace area of two traps is delineated by metal borders (1x4 m2) to relate erosion rates to a known drainage area. The sediment traps are emptied after all rainfall events. At the beginning and end of the rainy season, a laser scanning survey of a terrace located uphill of the ones</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.455.2345W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.455.2345W"><span id="translatedtitle">Integral <span class="hlt">field</span> spectroscopy of massive young stellar objects in the N113 H II <span class="hlt">region</span> in the Large Magellanic Cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ward, J. L.; Oliveira, J. M.; van Loon, J. Th.; Sewiło, M.</p> <p>2016-01-01</p> <p>The Spitzer Surveying the Agents of Galaxy Evolution (SAGE) survey has allowed the identification and analysis of significant samples of Young Stellar Object (YSO) candidates in the Large Magellanic Cloud (LMC). However, the angular resolution of Spitzer is relatively poor meaning that at the distance of the LMC, it is likely that many of the Spitzer YSO candidates in fact contain multiple components. We present high-resolution K-band integral <span class="hlt">field</span> spectroscopic observations of the three most prominent massive YSO candidates in the N113 H II <span class="hlt">region</span> using Very Large Telescope/Spectrograph for INtegral <span class="hlt">Field</span> Observations in the Near Infrared (VLT/SINFONI). We have identified six K-band continuum sources within the three Spitzer sources and we have mapped the morphology and velocity <span class="hlt">fields</span> of extended line emission around these sources. Br γ, He I and H2 emission is found at the position of all six K-band sources; we discuss whether the emission is associated with the continuum sources or whether it is ambient emission. H2 emission appears to be mostly ambient emission and no evidence of CO emission arising in the discs of YSOs has been found. We have mapped the centroid velocities of extended Br γ emission and He I emission and found evidence of two expanding compact H II <span class="hlt">regions</span>. One source shows compact and strong H2 emission suggestive of a molecular outflow. The diversity of spectroscopic properties observed is interpreted in the context of a range of evolutionary stages associated with massive star formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014RMxAC..44..190B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014RMxAC..44..190B"><span id="translatedtitle">Two-dimensional kinematics of the central <span class="hlt">region</span> of NGC4501 from GMOS/Gemini integral <span class="hlt">field</span> spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brum, C.; Riffel, R. A.; Storchi-Bergmann, T.; Schnorr Muller, A.; Robinson, A.</p> <p>2014-10-01</p> <p>We present two-dimensional stellar and gas kinematics in the central <span class="hlt">region</span> of the Seyfert 2 galaxy NGC 4501 from optical Integral <span class="hlt">Field</span> Spectroscopy obtained with Gemini Multi-Object Spectrograph (GMOS) at Gemini-North telescope. The final data cube contains ˜ 16000 spectra covering the inner 7" × 15" at spatial resolution of ˜ 50 pc and covering the spectral <span class="hlt">region</span> from 5600 Å to 7000 Å at a spectral resolution of 2.7 Å (FWHM). Two-dimensional maps for the flux, velocity and velocity dispersion (σ) were obtained from the fitting of the emission-line profiles of Hα, [N II] λ λ 6548,6584 and [S II] λ λ 6717,6731. All lines present extended emission to up to 5" the peak of flux of the nuclear at it. The gas velocity <span class="hlt">field</span> for all lines are similar, being dominated by rotation in the plane of the galaxy with a velocity amplitude of 100 km^{-1}, although deviations from rotation are seen at some locations. On the far side of the galaxy we observed blueshifts and on the near side redshifts along spiral structures, being interpreted as inflows towards the nucleus of NGC 4501. The forbidden lines show σ values ranging from 50 to 150 km s^{-1} while the Hα shows overall smaller values, with the highest ones reaching ˜ 100 km s^{-1}. The highest σ values for all emission lines are observed at 2-3 arcsec northeast from the nucleus, being co-spatial with a distortion seen in the velocity <span class="hlt">field</span>. The electron density map obtained from the [S II] λ λ 6731/6716 line ratio shows values between 100 cm^{-3} the nucleus to 900 cm^{-3} in a ring of high densities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007884','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007884"><span id="translatedtitle">Space Technology 5 (ST-5) Observations of the Imbalance of <span class="hlt">Region</span> 1 and 2 <span class="hlt">Field</span>-Aligned Currents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Le, Guan</p> <p>2010-01-01</p> <p>Space Technology 5 (ST-5) is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, sun-synchronous polar orbit from March 22 to June 21, 2006, for technology validations. In this study, we use the in-situ magnetic <span class="hlt">field</span> observations from Space Technology 5 mission to quantify the imbalance of <span class="hlt">Region</span> 1 (R1) and <span class="hlt">Region</span> 2 (R2) currents. During the three-month duration of the ST5 mission, geomagnetic conditions range from quiet to moderately active. We find that the R1 current intensity is consistently stronger than the R2 current intensity both for the dawnside and the duskside large-scale <span class="hlt">field</span>-aligned current system. The net currents flowing into (out of) the ionosphere in the dawnside (duskside) are in the order of 5% of the total RI currents. We also find that the net currents flowing into or out of the ionosphere are controlled by the solar wind-magnetosphere interaction in the same way as the <span class="hlt">field</span>-aligned currents themselves are. Since the net currents due to the imbalance of the R1 and R2 currents require that their closure currents flow across the polar cap from dawn to dusk as Pedersen currents, our results indicate that the total amount of the cross-polar cap Pedersen currents is in the order of approx. 0.1 MA. This study, although with a very limited dataset, is one of the first attempts to quantify the cross-polar cap Pedersen currents. Given the importance of the Joule heating due to Pedersen currents to the high-latitude ionospheric electrodynamics, quantifying the cross-polar cap Pedersen currents and associated Joule heating is needed for developing models of the magnetosphere-ionosphere coupling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.5815I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.5815I"><span id="translatedtitle">Extreme regimes of atmospheric circulation and their role in the formation of temperature and precipitation <span class="hlt">fields</span> in the Arctic <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Irina, Kulikova; Ekaterina, Kruglova; Dmitry, Kiktev; Vladimir, Tischenco; Valentina, Khan</p> <p>2016-04-01</p> <p>In the present study, the extreme regimes of atmospheric circulation in the Northern Hemisphere as well as their role in the formation of monthly and seasonal anomalies of temperature and precipitation <span class="hlt">fields</span> over Arctic <span class="hlt">region</span> were examined using NCEP / NCAR-2 reanalysis data. To identify extreme modes, climate indexes were quantitatively assessed. The mapping of monthly and seasonal temperature and precipitation <span class="hlt">fields</span> for the different phases of indices using composite analysis was developed. It is allowed to identify allocated geographic areas in which the influence of modes of circulation for temperature and precipitation <span class="hlt">fields</span> in Arctic is statistically significant. Quantitative estimations of contingency of atmospheric circulation modes in the Northern Hemisphere were analyzed. Special attention has been paid to the extreme episodes of the climate circulation indices, associated with formation of significant anomalies of air temperature and precipitation. The results of numerical experiments to reproduce the extreme events on monthly and seasonal time scale on the basis of the global semi-Lagrangian model SL-AV, developed in collaboration of Institute of Numerical Mathematics and Hydrometeorological Centre of Russia, have been discussed. For this study the support has been provided by Grant of Russian Science Foundation (№14-37-00053).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRD..118.6493G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRD..118.6493G"><span id="translatedtitle">Simulating smoke transport from wildland fires with a <span class="hlt">regional</span>-scale air quality model: Sensitivity to uncertain wind <span class="hlt">fields</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garcia-Menendez, Fernando; Hu, Yongtao; Odman, Mehmet Talat</p> <p>2013-06-01</p> <p>Uncertainties associated with meteorological inputs which are propagated through atmospheric chemical transport models may constrain their ability to replicate the effects of wildland fires on air quality. Here, we investigate the sensitivity of predicted fine particulate matter (PM2.5) levels to uncertain wind <span class="hlt">fields</span> by simulating the air quality impacts of two fires on an urban area with the Community Multiscale Air Quality modeling system (CMAQ). Brute-force sensitivity analyses show that modeled concentrations at receptors downwind from the fires are highly sensitive to variations in wind speed and direction. Additionally, uncertainty in wind <span class="hlt">fields</span> produced with the Weather Research and Forecasting model was assessed by evaluating meteorological predictions against surface and upper air observations. Significant differences between predicted and observed wind <span class="hlt">fields</span> were identified. Simulated PM2.5 concentrations at urban sites displayed large sensitivities to wind perturbations within the error range of meteorological inputs. The analyses demonstrate that normalized errors in CMAQ predictions attempting to model the <span class="hlt">regional</span> impacts of fires on PM2.5 levels could be as high as 100% due to inaccuracies in wind data. Meteorological drivers may largely account for the considerable discrepancies between monitoring site observations and predicted concentrations. The results of this study demonstrate that limitations in fire-related air quality simulations cannot be overcome by solely improving emission rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cancer.gov/espanol/tipos/seno/investigacion/resultados-star-respuestas','NCI'); return false;" href="https://www.cancer.gov/espanol/tipos/seno/investigacion/resultados-star-respuestas"><span id="translatedtitle">Preguntas y respuestas acerca del <span class="hlt">Estudio</span> del</span></a></p> <p><a target="_blank" href="http://www.cancer.gov">Cancer.gov</a></p> <p></p> <p></p> <p>El <span class="hlt">Estudio</span> del Tamoxifeno y Raloxifeno (STAR, por sus siglas en ingls) es un <span class="hlt">estudio</span> clnico (un <span class="hlt">estudio</span> de investigacin conducido con voluntarios) diseado para ver cómo el medicamento raloxifeno (Evista) se compara con el medicamento tamoxifeno (Nolvadex)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030064881','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030064881"><span id="translatedtitle"><span class="hlt">Regional</span> Impacts of Woodland Expansion on Nitrogen Oxide Emissions from Texas Savannahs: Combining <span class="hlt">Field</span>, Modeling and Remote Sensing Approaches</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Asner, Gregory P. (Principal Investigator)</p> <p>2003-01-01</p> <p>Woody encroachment has contributed to documented changes world-wide and locally in the southwestern U.S. Specifically, in North Texas rangelands encroaching mesquite (Prosopis glandulosa var. glandulosa) a known N-fixing species has caused changes in aboveground biomass. While measurements of aboveground plant production are relatively common, measures of soil N availability are scarce and vary widely. N trace gas emissions (nitric and nitrous oxide) flom soils reflect patterns in current N cycling rates and availability as they are stimulated by inputs of organic and inorganic N. Quantification of N oxide emissions from savanna soils may depend upon the spatial distribution of woody plant canopies, and specifically upon the changes in N availability and cycling and subsequent N trace gas production as influenced by the shift from herbaceous to woody vegetation type. The main goal of this research was to determine whether remotely sensible parameters of vegetation structure and soil type could be used to quantify biogeochemical changes in N at local, landscape and <span class="hlt">regional</span> scales. To accomplish this goal, <span class="hlt">field</span>-based measurements of N trace gases were carried out between 2000-2001, encompassing the acquisition of imaging spectrometer data from the NASA Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) on September 29, 2001. Both biotic (vegetation type and soil organic N) and abiotic (soil type, soil pH, temperature, soil moisture, and soil inorganic N) controls were analyzed for their contributions to observed spatial and temporal variation in soil N gas fluxes. These plot level studies were used to develop relationships between spatially extensive, <span class="hlt">field</span>-based measurements of N oxide fluxes and remotely sensible aboveground vegetation and soil properties, and to evaluate the short-term controls over N oxide emissions through intensive <span class="hlt">field</span> wetting experiments. The relationship between N oxide emissions, remotely-sensed parameters (vegetation cover, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.H41B0399A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.H41B0399A"><span id="translatedtitle">A Nested Modeling Scheme for High-resolution Simulation of the Aquitard Compaction in a <span class="hlt">Regional</span> Groundwater Extraction <span class="hlt">Field</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aichi, M.; Tokunaga, T.</p> <p>2006-12-01</p> <p>In the <span class="hlt">fields</span> that experienced both significant drawdown/land subsidence and the recovery of groundwater potential, temporal change of the effective stress in the clayey layers is not simple. Conducting consolidation tests of core samples is a straightforward approach to know the pre-consolidation stress. However, especially in the urban area, the cost of boring and the limitation of sites for boring make it difficult to carry out enough number of tests. Numerical simulation to reproduce stress history can contribute to selecting boring sites and to complement the results of the laboratory tests. To trace the effective stress profile in the clayey layers by numerical simulation, discretization in the clayey layers should be fine. At the same time, the size of the modeled domain should be large enough to calculate the effect of <span class="hlt">regional</span> groundwater extraction. Here, we developed a new scheme to reduce memory consumption based on domain decomposition technique. A finite element model of coupled groundwater flow and land subsidence is used for the local model, and a finite difference groundwater flow model is used for the <span class="hlt">regional</span> model. The local model is discretized to fine mesh in the clayey layers to reproduce the temporal change of pore pressure in the layers while the <span class="hlt">regional</span> model is discretized to relatively coarse mesh to reproduce the effect of the <span class="hlt">regional</span> groundwater extraction on the groundwater flow. We have tested this scheme by comparing the results obtained from this scheme with those from the finely gridded model for the entire calculation domain. The difference between the results of these models was small enough and our new scheme can be used for the practical problem.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B43I0668T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B43I0668T"><span id="translatedtitle">Large differences in global and <span class="hlt">regional</span> soil carbon stocks estimated by different products: intercomparison and evaluation with <span class="hlt">field</span> measurements.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tifafi, M.; Guenet, B.</p> <p>2015-12-01</p> <p>Soils are the major component of the terrestrial ecosystem and the largest organic carbon reservoir on Earth. However, it's a non-renewable natural resource and quite reactive to human disturbance and climate change. Even small modifications, of less than a percent, of the huge amount of carbon contained in soils may lead to sources or sinks of greenhouse gases that could be significant relative to those released by fossil fuel combustion. Consequently, soil carbon dynamic is an important source of uncertainties for future climate predictions. To tackle this difficulty, there is a growing need for global and specific information on the soils to better understand the mechanisms controlling soil carbon dynamic and better constraints the Earth system models. Several global information systems on soil parameters already exist but these products are not always consistent and lack of spatial details. The aim of our work is to compare the soil organic carbon stock given by different products : The World Soil Information (ISRIC), the Harmonized World Soil Database (HWSD) and The Northern Circumpolar Soil Carbon Database (NCSCD) and better understand what are the main differences that may explain the inconstencies between the products. We calculated global and <span class="hlt">regional</span> soil carbon stocks with the three products at different depths and we observed that they may largely differ in particular in boreal <span class="hlt">regions</span>. We also observed bigger differences in the stocks estimated for surface soils compare to deep soils. Differences in boreal <span class="hlt">regions</span> may be due to high disparities in soil organic carbon concentration whereas differences in other <span class="hlt">regions</span> may be more likely due to different bulk densities. Finally, we compared the three products with <span class="hlt">field</span> data available within the International Soil Carbon Network and we observed that each products present important drawbacks in representing the spatial variability. The estimation of the global soil carbon stocks is still quite uncertain</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.3218G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.3218G"><span id="translatedtitle">Ellipsoidal Harmonic Vertical Deflections. Global and <span class="hlt">Regional</span> Modeling of The Horizontal Derivative of The Terrestrial Garvity <span class="hlt">Field</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grafarend, E. W.; Ardalan, A.; Finn, G.</p> <p></p> <p>In terms of elliptic coordinates of Jacobi type (longitude, latitude, semi-minor axis) the horizontal derivative is computed as a linear operator acting on an ellipsoidal har- monic disturbing/incremental gravitational potential. Such disturbing potential is de- fined with respect to the Somigliana-Pizzetti Reference Potential, the potential <span class="hlt">field</span> of a level ellipsoid, and the International Reference Ellipsoid/WGS84 or World Geode- tic Datum 2000/WGD2000. Case studies of those vertical deflections on a global as well as <span class="hlt">regional</span> scale are presented which take advantage of SEGEN (Special Ellipsoidal Gravity Earth Normal: ellipsoidal harmonics expansion 130321 coeffi- cients: http://www.uni-stuttgart.de/gi/research/paper/coefficients/coefficients.zip) and of CENT (precise centrifugal potential)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.1015D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.1015D"><span id="translatedtitle">Altitude development of postmidnight F <span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities observed using Equatorial Atmosphere Radar in Indonesia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dao, Tam; Otsuka, Yuichi; Shiokawa, Kazuo; Tulasi Ram, S.; Yamamoto, Mamoru</p> <p>2016-02-01</p> <p>For the first time, vertical rise velocities of postmidnight <span class="hlt">field</span>-aligned irregularities (FAIs) at low geomagnetic latitudes have been examined near the June solstice by using two-dimensional maps of F <span class="hlt">region</span> FAI echoes observed with the Equatorial Atmosphere Radar in Indonesia for 3 years starting in May 2010. We found 15 freshly growing FAIs at postmidnight between May and August during the 3 years. The rise velocities of FAIs are smaller at postmidnight than at postsunset, and most postmidnight FAIs do not exceed an altitude of 450 km. Based on the rise velocities, a lower limit for the creation time of the postmidnight FAIs is estimated to be between 21:30 LT and 02:00 LT for 14 of the 15 events, indicating that this class of FAIs is distinct from the postsunset FAIs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20050947','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20050947"><span id="translatedtitle">In-<span class="hlt">field</span> results of SNCR/SCR hybrid on a group 1 boiler in the ozone transport <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Boyle, J.M.; Urbas, J.</p> <p>1998-07-01</p> <p>Electric utilities within the Ozone Transport <span class="hlt">Region</span> must prepare for seasonal and potentially piecemeal NO{sub x} reductions to meet Title 1 requirements. In order to achieve additional NO{sub x} reductions beyond the existing SNCR System in a manner, which allows maximum flexibility at minimum cost. GPU GENCO, in cooperation with the DOE, EPRI, PETC, and PERC, has chosen to <span class="hlt">field</span> demonstrate a SNCR/SCR hybrid system. Commercially known as NO{sub x}OUT CASCADE, the system employs a urea based SNCR system to produce a managed level of ammonia slip, which in turn charges an in duct SCR element. The system is presently scheduled for initial operation in October 1997. This paper discusses the decision path associated with the project, including design and operating criteria, performance expectations, retrofit considerations, testing protocol, and current results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/645471','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/645471"><span id="translatedtitle">Calculation of population doses with RADTRAN for route segments that have an unpopulated near-<span class="hlt">field</span> <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kanipe, F.L.; Neuhauser, S.; Sprung, J.L.</p> <p>1998-03-01</p> <p>The RADTRAN code (Neuhauser and Kanipe, 1994) models the radiological consequences of the transportation of radioactive materials, both the exposures that will occur if the transport occurs without incident, and the exposures that may occur should the transport vehicle be involved in an accident while en route. Because accidents might occur at any point along a transportation route, RADTRAN divides the route into segments (links) and uses a uniform population density and constant meteorological conditions (wind speed and atmospheric stability) to represent the population and weather characteristics of each route segment. A way to perform RADTRAN calculations, that allows an unpopulated near-<span class="hlt">field</span> <span class="hlt">region</span> along a transportation link to be approximately modeled, is described, validated, and then illustratively applied to a coastal sailing route.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960015526','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960015526"><span id="translatedtitle">Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis <span class="hlt">Region</span> and <span class="hlt">Field</span> Trips in the Channeled Scabland, Washington</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W., Jr. (Editor)</p> <p>1995-01-01</p> <p>This volume, the first of two comprising the technical report for this workshop, contains papers that have been accepted for presentation at the Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis <span class="hlt">Region</span>, September 24-30, 1995, in Spokane, Washington. The Mars Pathfinder Project received a new start in October 1993 as one of the next missions in NASA's long-term Mars exploration program. The mission involves landing a single vehicle on the surface of Mars in 1997. The project is one of the first Discovery-class missions and is required to be a quick, low-cost mission and achieve a set of significant but focused engineering, science, and technology objectives. The primary objective is to demonstrate a low-cost cruise, entry, descent, and landing system required to place a payload on the martian surface in a safe, operational configuration. Additional objectives include the deployment and operation of various science instruments and a microrover. Pathfinder paves the way for a cost-effective implementation of future Mars lander missions. Also included in this volume is the <span class="hlt">field</span> trip guide to the Channeled Scabland and Missoula Lake Break-out. On July 4, 1997, Mars Pathfinder is scheduled to land near 19.5 deg N, 32.8 deg W, in a portion of Ares Vallis. The landing ellipse covers a huge (100 x 200 km) area that appears to include both depositional and erosional landforms created by one or more giant, catastrophic floods. One of the best known terrestrial analogs to martian outflow channels (such as Ares Vallis) is the <span class="hlt">region</span> known as the Channeled Scabland. The <span class="hlt">field</span> trip guide describes some of the geomorphological features of the Channeled Scabland and adjacent Lake Missoula break-out area near Lake Pend Oreille, Idaho.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23919308','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23919308"><span id="translatedtitle">Characterization of <span class="hlt">field</span> and vaccine infectious bursal disease viruses from Nigeria revealing possible virulence and <span class="hlt">regional</span> markers in the VP2 minor hydrophilic peaks.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Adamu, J; Owoade, A A; Abdu, P A; Kazeem, H M; Fatihu, M Y</p> <p>2013-01-01</p> <p>Outbreaks of infectious bursal disease in vaccinated chicken flocks are frequent in Nigeria. For the control of infectious bursal disease, live vaccines based on foreign infectious bursal disease virus (IBDV) strains are used. The present study investigated the phylogenetic relationship between <span class="hlt">field</span> and vaccine IBDV strains from northwestern Nigeria. Thirty <span class="hlt">field</span> IBDV strains and three commercial vaccines strains were characterized through sequencing the VP2 hypervariable <span class="hlt">region</span>. In addition, the complete genome segment A coding <span class="hlt">region</span> for two vaccines and two <span class="hlt">field</span> strains was sequenced. The deduced amino acid sequences (position 212 to 331) of IBDV strains from Nigeria and other <span class="hlt">regions</span> of the world were aligned and possible <span class="hlt">regional</span> and virulence markers were identified associated with VP2 minor hydrophilic peaks. Reversion to virulence of a vaccine strain with a Q to L mutation at position 253 was observed. Phylogenetic analyses revealed a unique cluster of northwest Nigerian <span class="hlt">field</span> IBDV strains alone or related to imported characterized classical and very virulent IBDV vaccines. The results suggest that when IBDV strains spread from their <span class="hlt">region</span> of origin to a different <span class="hlt">region</span> they mutate alongside indigenous <span class="hlt">field</span> strains but may retain their identity on the VP2 <span class="hlt">region</span>. PMID:23919308</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4516F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4516F"><span id="translatedtitle">Temperature <span class="hlt">field</span> and heat flow of the Danish-German border <span class="hlt">region</span> - borehole measurements and numerical modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuchs, Sven; Balling, Niels</p> <p>2016-04-01</p> <p>We present a <span class="hlt">regional</span> 3D numerical crustal temperature model and analyze the present-day conductive thermal <span class="hlt">field</span> of the Danish-German border <span class="hlt">region</span> located in the North German Basin. A comprehensive analysis of borehole and well-log data on a <span class="hlt">regional</span> scale is conducted to derive both the model parameterization with a spatial distribution of rock thermal conductivity and new heat-flow values. The latter one are used to setup the numerical lower boundary condition. Measured heat flow and borehole temperature observations (59 values from 24 wells) are used to constrain the modelling results (calibration and validation). The prediction uncertainties between observed and modelled temperatures at deep borehole sites are small (rms = 3.5°C). For eight deep boreholes, new values of terrestrial surface heat flow are derived, ranging between 72 and 84 mW/m² (mean of 80 ± 5 mW/m²). Those values are up to 20 mW/m² higher than low values reported in some previous studies for this <span class="hlt">region</span>. Heat flow from the mantle is estimated to be between 33 and 40 mW/m² (q1-q3; mean of 37 ± 7 mW/m²). Pronounced lateral temperature variations are caused mainly by complex geological structures, including a large amount of salt structures and marked lateral variations in the thickness of basin sediments. The associated variations in rock thermal conductivity generate significant variations in model heat flow and large variations in temperature gradients. Major geothermal sandstone reservoirs (e.g. Rhaetian and Middle Buntsandstein) are mainly found with temperatures within the range of 40-80°C, which is suitable for low enthalpy heating purposes in most of the area. Higher temperatures of up to 120-160°C, of interest for the production of electricity, are observed only in the very south-eastern part of the study area (Glückstadt-Graben area). In combination with the structural geological model and information on reservoir hydraulic properties, the presented temperature model will</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT........29A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT........29A"><span id="translatedtitle">Effects of near-source heterogeneity on wave <span class="hlt">fields</span> emanating from crustal sources observed at <span class="hlt">regional</span> and teleseismic distances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Avants, Megan S.</p> <p></p> <p>Near-source path effects imprint the wave <span class="hlt">field</span> emanating from a seismic source and, if not well resolved, can obscure the details of source characteristics determined from observations of the seismic waves at <span class="hlt">regional</span> and teleseismic distances (≥200 km). These effects are particularly strong for crustal sources such as shallow earthquakes and underground nuclear explosions. First, I explore 2D effects of random seismic P-wave velocity heterogeneity resulting from volumetric heterogeneity in the upper mantle and variability of the Moho on the amplitude decay of the <span class="hlt">regional</span> phase Pn. Results indicate that the pattern of amplitude decay due to geometric spreading for a simple Earth model is more complex than that for an Earth model containing strong heterogeneity in the mantle lid. Next, I implement the representation theorem in a method which collects displacement and strain components output from a 3D finite difference program capable of including realistic surface topography and geologic structure in a 3D velocity model, and calculates teleseismic 3D Green functions (3DGFs) to specified receiver locations. Green functions produced from a 3D source model match Green functions produced from a 1D source model for theoretical source-receiver geometries. This new method is then applied to the problem of constraining the source depth and location of the three nuclear tests conducted by North Korea, by using a realistic topography model for the mountainous test <span class="hlt">region</span> to calculate 3DGFs for several possible locations of each event. Amplitude ratios of P and pP from 3DGFs are correlated to those in observed stacked traces. Results show a sensitivity of this method to source depth and location across the test site <span class="hlt">region</span> with source depths slightly greater than published estimates, but relative locations consistent with other studies. Finally, I determine a rupture model of the 2008 Wenchuan earthquake using 3DGFs calculated in a velocity model containing the dramatic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22130775','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22130775"><span id="translatedtitle">NEAR-INFRARED PERIODIC AND OTHER VARIABLE <span class="hlt">FIELD</span> STARS IN THE <span class="hlt">FIELD</span> OF THE CYGNUS OB7 STAR-FORMING <span class="hlt">REGION</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wolk, Scott J.; Rice, Thomas S.; Aspin, Colin A.</p> <p>2013-04-15</p> <p>We present a subset of the results of a three-season, 124 night, near-infrared monitoring campaign of the dark clouds Lynds 1003 and Lynds 1004 in the Cygnus OB7 star-forming <span class="hlt">region</span>. In this paper, we focus on the <span class="hlt">field</span> star population. Using three seasons of UKIRT J, H, and K-band observations spanning 1.5 years, we obtained high-quality photometry on 9200 stars down to J = 17 mag, with photometric uncertainty better than 0.04 mag. After excluding known disk-bearing stars we identify 149 variables-1.6% of the sample. Of these, about 60 are strictly periodic, with periods predominantly <2 days. We conclude this group is dominated by eclipsing binaries. A few stars have long period signals of between 20 and 60 days. About 25 stars have weak modulated signals, but it was not clear if these were periodic. Some of the stars in this group may be diskless young stellar objects with relatively large variability due to cool starspots. The remaining {approx}60 stars showed variations which appear to be purely stochastic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AnGeo..27.2711H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AnGeo..27.2711H"><span id="translatedtitle">Artificial E-<span class="hlt">region</span> <span class="hlt">field</span>-aligned plasma irregularities generated at pump frequencies near the second electron gyroharmonic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hysell, D. L.; Nossa, E.</p> <p>2009-07-01</p> <p>E <span class="hlt">region</span> ionospheric modification experiments have been performed at HAARP using pump frequencies about 50 kHz above and below the second electron gyroharmonic frequency. Artificial E <span class="hlt">region</span> <span class="hlt">field</span>-aligned plasma density irregularities (FAIs) were created and observed using the imaging coherent scatter radar near Homer, Alaska. Echoes from FAIs generated with pump frequencies above and below 2Ωe did not appear to differ significantly in experiments conducted on summer afternoons in 2008, and the resonance instability seemed to be at work in either case. We argue that upper hybrid wave trapping and resonance instability at pump frequencies below the second electron gyroharmonic frequency are permitted theoretically when the effects of finite parallel wavenumbers are considered. Echoes from a sporadic E layer were observed to be somewhat weaker when the pump frequency was 50 kHz below the second electron gyroharmonic frequency. This may indicate that finite parallel wavenumbers are inconsistent with wave trapping in thin sporadic E ionization layers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013RaSc...48..482M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013RaSc...48..482M"><span id="translatedtitle">Reexamining X-mode suppression and fine structure in artificial E <span class="hlt">region</span> <span class="hlt">field</span>-aligned plasma density irregularities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miceli, R. J.; Hysell, D. L.; Munk, J.; McCarrick, M.; Huba, J. D.</p> <p>2013-09-01</p> <p>Artificial <span class="hlt">field</span>-aligned plasma density irregularities (FAIs) were generated in the E <span class="hlt">region</span> of the ionosphere above the High Frequency Active Auroral Research Program facility during campaigns in May and August of 2012 and observed using a 30 MHz coherent scatter radar imager in Homer, Alaska. The purpose of this ionospheric modification experiment was to measure the threshold pump power required to excite thermal parametric instabilities by O-mode heating and to investigate the suppression of the FAIs by simultaneous X-mode heating. We find that the threshold pump power for irregularity excitation was consistent with theoretical predictions and increased by approximately a factor of 2 when X-mode heating was present. A modified version of the Another Model of the Ionosphere (SAMI2) ionospheric model was used to simulate the threshold experiments and suggested that the increase was entirely due to enhanced D <span class="hlt">region</span> absorption associated with X-mode heating. Additionally, a remarkable degree of fine structure possibly caused by natural gradient drift instability in the heater-modified volume was observed in experiments performed during geomagnetically active conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APhy...61...28R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APhy...61...28R"><span id="translatedtitle">Diffraction of high-intensity <span class="hlt">field</span> in focal <span class="hlt">region</span> as dynamics of nonlinear system with low-frequency dispersion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rudenko, O. V.; Hedberg, C. M.</p> <p>2015-01-01</p> <p>The stationary profile in the focal <span class="hlt">region</span> of a focused nonlinear acoustic wave is described. Three models following from the Khokhlov-Zabolotskaya (KZ) equation with three independent variables are used: (i) the simplified one-dimensional Ostrovsky-Vakhnenko equation, (ii) the system of equations for paraxial series expansion of the acoustic <span class="hlt">field</span> in powers of transverse coordinates, and (iii) the KZ equation reduced to two independent variables. The structure of the last equation is analogous to the Westervelt equation. Linearization through the Legendre transformation and reduction to the well-studied Euler-Tricomi equation is shown. At high intensities the stationary profiles are periodic sequences of arc sections having singularities of derivative in their matching points. The occurrence of arc profiles was pointed out by Makov. These appear in different nonlinear systems with low-frequency dispersion. Profiles containing discontinuities (shock fronts) change their form while passing through the focal <span class="hlt">region</span> and are non-stationary waves. The numerical estimations of maximum pressure and intensity in the focus agree with computer calculations and experimental measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.3750L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.3750L"><span id="translatedtitle">Coordinated observations of F <span class="hlt">region</span> 3 m <span class="hlt">field</span>-aligned plasma irregularities associated with medium-scale traveling ionospheric disturbances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, F. F.; Wang, C. Y.; Su, C. L.; Shiokawa, K.; Saito, S.; Chu, Y. H.</p> <p>2016-04-01</p> <p>Three meter <span class="hlt">field</span>-aligned irregularities (3 m FAIs) associated with medium-scale traveling ionospheric disturbances (MSTIDs) that occurred on 5 February 2008 were observed by using the Chung-Li 52 MHz coherent scatter radar. Interferometry measurements show that the plasma structures responsible for the 3 m FAI echoes are in a clumpy shape with a horizontal dimension of about 10-78 km in a height range of 220-300 km. In order to investigate the dynamic behaviors of the plasma irregularities at different scales in the bottomside of F <span class="hlt">region</span>, the VHF radar echo structures from the 3 m FAIs combined with the 630 nm airglow images provided by the Yonaguni all-sky imager are compared and analyzed. The results show that the radar echoes were located at the west edge of the depletion zones of the 630 nm airglow image of the MSTIDs. The bulk echo structures of the 3 m FAIs drifted eastward at a mean trace velocity of about 30 m/s that is in general agreement with the zonal trace velocity of the MSTIDs shown in the 630 nm airglow images. These results suggest that the observed F <span class="hlt">region</span> 3 m FAIs for the present case can be regarded as the targets that are frozen in the local <span class="hlt">region</span> of the MSTIDs. In addition, the radar-observed 3 m FAI echo intensity and spectral width bear high correlations to the percentage variations of the 630 nm emission intensity. These results seem to suggest that through the nonlinear turbulence cascade process, the MSTID-associated 3 m FAIs are very likely generated from the kilometer-scale plasma irregularities with large amplitude excited by the gradient drift instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5796807','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5796807"><span id="translatedtitle">Multiple frequency backscatter observations of heater-induced <span class="hlt">field</span>-aligned striations in the auroral E <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Noble, S.T.</p> <p>1985-01-01</p> <p>In September 1983 a series of HF ionospheric modification experiments were conducted in Scandinavia using the heat facility near Tromosoe Norway. The purpose of these experiments was to examine the mechanisms by which high-power HF radio waves produce geomagnetic <span class="hlt">field</span>-aligned striations (FAS) in the auroral E <span class="hlt">region</span>. The vast majority of the backscatter observations were made with radars operating at 47 and 144 MHz (STARE Finland). Additionally, limited observations were conducted at 140 (STARE Norway) and 21 MHz (SAFARI). These radars are sensitive to irregularities having scale lengths between 1 and 7 m across the geomagnetic <span class="hlt">field</span> lines. During periods of full power O-mode heating, striations having peak cross sections of 40 to 50 dBsm are observed. Striations are not detected during times of X-mode heating. When the heater output is varied, a corresponding change in the cross section is measured. The magnitude of the change is most pronounced for heater level changes in the range 12.5 to 50% of full power. These cross sections are significantly larger than those measured at midlatitudes using the Arecibo heater (approx.10/sup 1/ m/sup 2/). This is consistent with theoretical studies which indicate that it is easier to excite short-scale FAS at places where the geomagnetic dip angle is large. The growth and decay times of the striations are frequency dependent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000AcO....21....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000AcO....21....1C"><span id="translatedtitle">Early post-fire regeneration dynamics of Brachypodium retusum Pers. (Beauv.) in old <span class="hlt">fields</span> of the Valencia <span class="hlt">region</span> (eastern Spain)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caturla, Rosa N.; Raventós, Jose; Guàrdia, Roser; Vallejo, V. Ramon</p> <p>2000-01-01</p> <p>Extensive wildfires have affected the Valencia <span class="hlt">region</span> in the last two decades. A large portion of the burnt areas has been localised in old <span class="hlt">fields</span>. Although Mediterranean communities are usually resilient to fire and recover very quickly to the pre-fire state, burnt old <span class="hlt">fields</span> with a low number of species could show poor recovery capacity. The response capacity of these systems to fire, and, especially, the role of the native herbaceous Brachypodium retusum were studied. Two years after fire, plant cover reached a value of 56 %. Resprouter species were more important in number and in specific cover. B. retusum represented the species with the highest contribution to total plant cover for all the study period. Total biomass in burnt plots was always lower than in unburnt plots. However, B. retusum green biomass showed a quick recovery to pre-disturbance levels, and below-ground biomass was similar in burnt and unburnt plots. Reproductive biomass greatly increased in burnt with respect to unburnt plots during the first post-fire year, with no stalk production in unburnt plots. B. retusum may be considered a promising species for the restoration of extremely degraded lands because of its high resilience to fire.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22220649','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22220649"><span id="translatedtitle">On the applicability of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> in a tokamak edge <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dorf, M. A.; Cohen, R. H.; Joseph, I.; Simakov, A. N.</p> <p>2013-08-15</p> <p>The use of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> E{sub r}, i.e., the Ampere (or gyro-Poisson) equation, requires accurate calculation of the difference between the gyroaveraged electron and ion particle fluxes (or densities). In the core of a tokamak, the nontrivial difference appears only in high-order corrections to a local Maxwellian distribution due to the intrinsic ambipolarity of particle transport. The evaluation of such high-order corrections may be inconsistent with the accuracy of the standard long wavelength gyrokinetic equation (GKE), thus imposing limitations on the applicability of the standard approaches. However, in the edge of a tokamak, charge-exchange collisions with neutrals and prompt ion orbit losses can drive non-intrinsically ambipolar particle fluxes for which a nontrivial (E{sub r}-dependent) difference between the electron and ion fluxes appears already in a low order and can be accurately predicted by the long wavelength GKE. The parameter regimes, where the radial electric <span class="hlt">field</span> dynamics in the tokamak edge <span class="hlt">region</span> is dominated by the non-intrinsically ambipolar processes, thus allowing for the use of the standard approaches, are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1248311','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1248311"><span id="translatedtitle">On the applicability of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> in a tokamak edge <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dorf, M. A.; Cohen, R. H.; Simakov, A. N.; Joseph, I.</p> <p>2013-08-27</p> <p>The use of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> E<sub>r</sub>, i.e., the Ampere (or gyro-Poisson) equation, requires accurate calculation of the difference between the gyroaveraged electron and ion particle fluxes (or densities). In the core of a tokamak, the nontrivial difference appears only in high-order corrections to a local Maxwellian distribution due to the intrinsic ambipolarity of particle transport. The evaluation of such high-order corrections may be inconsistent with the accuracy of the standard long wavelength gyrokinetic equation (GKE), thus imposing limitations on the applicability of the standard approaches. However, in the edge of a tokamak, charge-exchange collisions with neutrals and prompt ion orbit losses can drive non-intrinsically ambipolar particle fluxes for which a nontrivial (E<sub>r</sub>-dependent) difference between the electron and ion fluxes appears already in a low order and can be accurately predicted by the long wavelength GKE. As a result, the parameter regimes where the radial electric <span class="hlt">field</span> dynamics in the tokamak edge <span class="hlt">region</span> is dominated by the non-intrinsically ambipolar processes, thus allowing for the use of the standard approaches, are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1248311-applicability-standard-approaches-evaluating-neoclassical-radial-electric-field-tokamak-edge-region','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1248311-applicability-standard-approaches-evaluating-neoclassical-radial-electric-field-tokamak-edge-region"><span id="translatedtitle">On the applicability of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> in a tokamak edge <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Dorf, M. A.; Cohen, R. H.; Simakov, A. N.; Joseph, I.</p> <p>2013-08-27</p> <p>The use of the standard approaches for evaluating a neoclassical radial electric <span class="hlt">field</span> Er, i.e., the Ampere (or gyro-Poisson) equation, requires accurate calculation of the difference between the gyroaveraged electron and ion particle fluxes (or densities). In the core of a tokamak, the nontrivial difference appears only in high-order corrections to a local Maxwellian distribution due to the intrinsic ambipolarity of particle transport. The evaluation of such high-order corrections may be inconsistent with the accuracy of the standard long wavelength gyrokinetic equation (GKE), thus imposing limitations on the applicability of the standard approaches. However, in the edge of a tokamak,more » charge-exchange collisions with neutrals and prompt ion orbit losses can drive non-intrinsically ambipolar particle fluxes for which a nontrivial (Er-dependent) difference between the electron and ion fluxes appears already in a low order and can be accurately predicted by the long wavelength GKE. As a result, the parameter regimes where the radial electric <span class="hlt">field</span> dynamics in the tokamak edge <span class="hlt">region</span> is dominated by the non-intrinsically ambipolar processes, thus allowing for the use of the standard approaches, are discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.5965M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.5965M"><span id="translatedtitle">Modeling of geomagnetic <span class="hlt">field</span> secular variations observed in the Balkan area for purposes of <span class="hlt">regional</span> topographic mapping</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Metodiev, Metodi; Trifonova, Petya; Buchvarov, Ivan</p> <p>2014-05-01</p> <p>The most significant of the Earth's magnetic <span class="hlt">field</span> elements is the geomagnetic declination, which is widely used in geodesy, cartography and their associated navigational systems. The geomagnetic declination is incorporated in the naval navigation maps and is used in the navigation process. It is also a very important factor for aviation where declination data have major importance for every airport (civil or military). As the geomagnetic <span class="hlt">field</span> changes with time but maps of the geomagnetic declination are not published annually and are reduced to an epoch in the past, it is necessary to define two additional parameters in the maps, needed to determine the value of the geomagnetic declination for a particular moment in the future: 1) estimated value of the annual declination variation and 2) a table with the average diurnal variation of the declination for a given month and hour. The goal of our research is to analyze the annual mean values of geomagnetic declination on the territory of the Balkan Peninsula for obtaining of a best fitting model of that parameter which can be used for prediction of the declination value for the next 10 years. The same study was performed in 1990 for the purposes of Bulgarian declination map's preparation. As a result, a linear model of the declination annual variation was obtained for the neighboring observatories and repeat stations data, and a map of the obtained values for the Bulgarian territory was drawn. We use the latest version of the GFZ Reference Internal Magnetic Model (GRIMM-3.0) to compare the magnetic <span class="hlt">field</span> evolution predicted by that model between 2001 and 2010 to the data collected in five independent geomagnetic observatories in the Balkan <span class="hlt">region</span> (PAG, SUA, PEG, IZN, GCK) over the same time interval. We conclude that the geomagnetic core <span class="hlt">field</span> secular variation in this area is well described by the global model. The observed small-scale differences might indicate induced lithospheric anomalies but it is still an open</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.T51K..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.T51K..04S"><span id="translatedtitle">Deep versus shallow controlling factors of the <span class="hlt">regional</span> thermal <span class="hlt">field</span> in the Beaufort-Mackenzie Basin (Arctic Canada)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scheck-Wenderoth, M.; Sippel, J.; Lewerenz, B.</p> <p>2011-12-01</p> <p>The present-day temperature distribution of the Beaufort-Mackenzie Basin as observed in boreholes indicates large-scale thermal anomalies which have been related to specific tectonic domains and heat transported by convection along major discontinuities (Chen et al., 2008). We have integrated seismic and well data into a crust-scale 3D structural model of the basin, which we have additionally constrained by 3D gravity modelling. This structural model is composed of seven Mesozoic-Cenozoic tectonostratigraphic units which - as a result of a complex foreland depositional and erosional history - tend to be younger, less compacted, and thus less thermally conductive towards the north. The underlying continental crust comprises a low-density upper part (2720 kg/m3 ) and a moderately dense lower part (2850 kg/m3), and it thins considerably towards the north where it passes over to oceanic crust (2900 kg/m2 ). We use the structural model to calculate the 3D conductive thermal <span class="hlt">field</span> of the basin based on a Finite-Element method, thereby taking one step further towards a quantification of heat transporting processes in this petroliferous <span class="hlt">region</span>. For the validation of the modelling results, we make use of public domain temperature data from more than 230 wells reaching depths of up to 5000 m. Thermal conductivities are assigned to the different units according to available data sets including also the observed lithology-dependent relationship between conductivity and porosity in the <span class="hlt">region</span>. The upper boundary condition for the thermal calculations is provided by the well-known depth distribution of the base of permafrost (0 °C isotherm). Assuming a constant heat flow of 30 mW/m2 at the Moho, we find that the modelled temperatures are widely consistent with the observed temperatures in most parts of the basin. Only where large tectonic discontinuities structure the margins of the basin, the misfits are considerable, thus indicating convective heat transport to be an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1512846M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1512846M"><span id="translatedtitle">Refining <span class="hlt">regional</span> SOC estimates: Accounting for erosion induced within <span class="hlt">field</span> variability of the vertical distribution of SOC.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meersmans, Jeroen; Quine, Tim</p> <p>2013-04-01</p> <p>Recently, soil organic carbon (SOC) is considered as a dynamic soil property largely influencing soil quality and global C-cycling. Consequently, accurate mapping of SOC at the <span class="hlt">regional</span> or national scale becomes an important issue in order to help policymakers in developing an appropriate soil and climate change management strategy. So far, in these studies, only factors determining the spatial and temporal distribution of SOC at the landscape scale, such as soil type, land use (change), climate and agro-management, were considered. Despite the fact that a few recent studies incorporated as well the distribution of SOC with depth, resulting in an improved representation of the 3D distribution of SOC, most studies only considers topsoil and/or are characterized by simple sampling by site at rather coarse resolution. Consequently, they omit quantification of stable subsoil carbon buried in depositional areas and does not allow to clearly identify significant differences of SOC and erosion at the within <span class="hlt">field</span> scale. Hence, the variability of SOC at smaller scales in complex terrain driven by lateral soil transport processes (such as soil erosion), is still rather understudied and is not (well) presented in existing <span class="hlt">regional</span> SOC estimates. Nevertheless, incorporating this smaller level of spatial detail will most probably have a major influence on SOC mapping and <span class="hlt">regional</span> SOC stock dynamics' calculations. Consequently, there exists an urgent need in conducting an appropriate soil sampling strategy considering deeper layers and enabling us to detect significant patterns at detailed spatial levels. In this study we aim to unravel the variation of SOC depth distributions along typical hillslope transects under cropland (Devon, UK) and link these to soil redistribution rates and variations in C input, i.e. below and above ground biomass productivity. The radionuclide isotope Caesium-137 (137Cs) was used as proxy for erosion. Furthermore, a soil sampling strategy was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EGUGA..17.9551L&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EGUGA..17.9551L&link_type=ABSTRACT"><span id="translatedtitle">HAIC/HIWC <span class="hlt">field</span> campaign - investigating ice microphysics in high ice water content <span class="hlt">regions</span> of mesoscale convective systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leroy, Delphine; Fontaine, Emmanuel; Schwarzenboeck, Alfons; Strapp, J. Walter; Lilie, Lyle; Dezitter, Fabien; Grandin, Alice</p> <p>2015-04-01</p> <p>Despite existing research programs focusing on tropical convection, high ice water content (IWC) <span class="hlt">regions</span> in Mesoscale Convective Systems (MCS) - potentially encountered by commercial aircraft and related to reported in-service events - remain poorly documented either because investigation of such high IWC <span class="hlt">regions</span> was not of highest priority or because utilized instrumentation was not capable of providing accurate cloud microphysical measurements. To gather quantitative data in high IWC <span class="hlt">regions</span>, a multi-year international HAIC/HIWC (High Altitude Ice Crystals / High Ice Water Content) <span class="hlt">field</span> project has been designed including a first <span class="hlt">field</span> campaign conducted out of Darwin (Australia) in 2014. The French Falcon 20 research aircraft had been equipped among others with a state-of-the-art in situ microphysics package including the IKP (isokinetic evaporator probe which provides a reference measurement of IWC and TWC), the CDP (cloud droplet spectrometer probe measuring particles in the range 2-50 µm), the 2D-S (2D-Stereo, 10-1280 µm) and PIP (precipitation imaging probe, 100-6400 µm) optical array probes. Microphysical data collection has been performed mainly at -40°C and -30°C levels, whereas little data could be sampled at -50°C and at -15C/-10°C. The study presented here focuses on ice crystal size properties, thereby analyzing in detail the 2D image data from 2D-S and PIP optical array imaging probes. 2D images recorded with 2D-S and PIP were processed in order to extract a large variety of geometrical parameters, such as maximum diameter (Dmax), 2D surface equivalent diameter (Deq), and the corresponding number particle size distribution (PSD). Using the PSD information from both probes, a composite size distribution was then built, with sizes ranging from few tens of µm to roughly 10 mm. Finally, mass-size relationships for ice crystals in tropical convection were established in terms of power laws in order to compute median mass diameters MMDmax and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7657N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7657N"><span id="translatedtitle">Hydrological and erosion processes in terraced agricultural <span class="hlt">fields</span>: observations from a wet Mediterranean <span class="hlt">region</span> in northern Portugal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nunes, João Pedro; Bernard-Jannin, Léonard; Rodriguez-Blanco, María Luz; Marisa Santos, Juliana; Oliveira Alves Coelho, Celeste; Keizer, Jan Jacob</p> <p>2015-04-01</p> <p>Traditional agriculture in the mountainous humid <span class="hlt">regions</span> of the northwestern Iberian peninsula has relied on terraces for soil retention. In the last decades, a strong afforestation (in many cases with commercial species) has led to the appearance of large forest areas coexisting with traditional agricultural landscapes. Soil erosion research in this <span class="hlt">region</span> has therefore focused on the impact of forest management practices and associated disturbances such as wildfires. However, there has been little research on the impacts of traditional terracing practices on erosion, and therefore it has been difficult to connect forest research with the wider issue of sediment connectivity in this complex agroforestry landscape. This work tried to address this research gap by monitoring an agricultural terrace in the Caramulo mountains, northern Portugal, during two years. The <span class="hlt">field</span> site is located in a humid Mediterranean climate <span class="hlt">region</span>, with c. 1500 mm/y rainfall, overlaying granite bedrock; agricultural practices are a traditional rotation between winter pasture and summer (irrigated) corn cultivation. During this period, the soil properties of the terrace were characterized, and there was a continuous monitoring of rainfall, soil moisture and surface runoff at the outlet, as well as 1 or 2-weekly collections of runoff to measure sediment yield. Occasional measurements of vegetation cover and erosion features (rills) within the plot were also made. Preliminary results indicate that runoff generation occurred mostly due to saturation-excess, possibly linked with the accumulation of groundwater in the lower layers of the soil. After one of the largest events, there was a clear inflow of runoff from outside the terrace, through either the irrigation network linking all terraces or by resurfacing of groundwater. Sediment yield was linked with runoff, but sediment concentration was linked with vegetation cover and was highest during the early stages of pasture growth. However</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011A%26A...531A.112K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011A%26A...531A.112K"><span id="translatedtitle">The continuum intensity as a function of magnetic <span class="hlt">field</span>. I. Active <span class="hlt">region</span> and quiet Sun magnetic elements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kobel, P.; Solanki, S. K.; Borrero, J. M.</p> <p>2011-07-01</p> <p>Context. Small-scale magnetic <span class="hlt">fields</span> are major contributors to the solar irradiance variations. Hence, the continuum intensity contrast of magnetic elements in the quiet Sun (QS) network and in active <span class="hlt">region</span> (AR) plage is an essential quantity that needs to be measured reliably. Aims: By using Hinode/SP disk center data at a constant, high spatial resolution, we aim at updating results of earlier ground-based studies of contrast vs. magnetogram signal, and to look for systematic differences between AR plages and QS network. Methods: The <span class="hlt">field</span> strength, filling factor and inclination of the <span class="hlt">field</span> was retrieved by means of a Milne-Eddington inversion (VFISV code). As in earlier studies, we then performed a pixel-by-pixel study of 630.2 nm continuum contrast vs. apparent (i.e. averaged over a pixel) longitudinal magnetic <span class="hlt">field</span> over large <span class="hlt">fields</span> of view in ARs and in the QS. Results: The continuum contrast of magnetic elements reaches larger values in the QS (on average 3.7%) than in ARs (on average 1.3%). This could not be attributed to any systematic difference in the chosen contrast references, so that it mainly reflects an intrinsic brightness difference. The larger contrasts in the QS are in agreement with earlier, lower resolution results, although our values are larger due to our better spatial resolution. At Hinode's spatial resolution, moreover, the relationship between contrast and apparent longitudinal <span class="hlt">field</span> strength exhibits a peak at around 700 G in both the QS and ARs, whereas earlier lower resolution studies only found a peak in the QS and a monotonic decrease in ARs. We attribute this discrepancy both to our careful removal of the pores and their close surroundings affected by the telescope diffraction, as well as to the enhanced spatial resolution and very low scattered light of the Hinode Solar Optical Telescope. We verified that the magnetic elements producing the peak in the contrast curve are rather vertical in the AR and in the QS, so that the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25904510','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25904510"><span id="translatedtitle">Persistence and spreading of <span class="hlt">field</span> and vaccine strains of infectious laryngotracheitis virus (ILTV) in vaccinated and unvaccinated geographic <span class="hlt">regions</span>, in Brazil.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chacón, Jorge Luis; Núñez, Luis Fabian Naranjo; Vejarano, Maria Pilar; Parra, Silvana Hipatia Santander; Astolfi-Ferreira, Claudete Serrano; Ferreira, Antonio José Piantino</p> <p>2015-08-01</p> <p>Infectious laryngotracheitis (ILT) is a highly infectious respiratory disease that causes morbidity and mortality in commercial chickens. Despite the use of attenuated vaccines, ILT outbreaks have been described in broiler and long-lived birds. Molecular approaches, including polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing, are used to characterize ILT viruses (ILTVs) detected in vaccinated and unvaccinated geographical <span class="hlt">regions</span>. As part of an ILT control program implemented in a <span class="hlt">region</span> of commercial layer production, samples of conjunctiva, trachea, and trigeminal ganglia were collected from chickens in a vaccinated and quarantined <span class="hlt">region</span> over a period of 8 years after initiation of vaccination. To determine the origin of new ILT outbreaks in unvaccinated <span class="hlt">regions</span>, samples collected from ill chickens were also analyzed. Chicken embryo origin (CEO) vaccine viruses and the Bastos <span class="hlt">field</span> strain were detected circulating in healthy chickens in the vaccinated <span class="hlt">region</span>. CEO strains and <span class="hlt">field</span> viruses molecularly related to the Bastos strain were also detected outside of the quarantined <span class="hlt">region</span> in chickens showing clinical signs of ILT. This study reveals the persistence and circulation of a wild <span class="hlt">field</span> strain, despite the intensive use of tissue culture origin (TCO) and CEO vaccines in a quarantined <span class="hlt">region</span>. Spreading of CEO viruses to unvaccinated <span class="hlt">regions</span> and the capacity of this virus to establish latent infections and cause severe outbreaks were also observed. PMID:25904510</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PMB....59.7435B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PMB....59.7435B"><span id="translatedtitle">A formula for human average whole-body SARwb under diffuse <span class="hlt">fields</span> exposure in the GHz <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bamba, A.; Joseph, W.; Vermeeren, G.; Thielens, A.; Tanghe, E.; Martens, L.</p> <p>2014-12-01</p> <p>A simple formula to determine the human average whole-body SAR (SARwb) under realistic propagation conditions is proposed in the GHz <span class="hlt">region</span>, i.e. from 1.45 GHz to 5.8 GHz. The methodology is based on simulations of ellipsoidal human body models. Only the exposure (incident power densities) and the human mass are needed to apply the formula. Diffuse scattered illumination is addressed for the first time and the possible presence of a Line-of-Sight (LOS) component is addressed as well. As validation, the formula is applied to calculate the average whole-body SARwb in 3D heterogeneous phantoms, i.e. the virtual family (34 year-old male, 26 year-old female, 11 year-old girl, and 6 year-old boy) and the results are compared with numerical ones—using the Finite-Difference Time-Domain (FDTD) method—at 3 GHz. For the LOS exposure, the average relative error varies from 28% to 12% (resp. 14-12%) for the vertical polarization (resp. horizontal polarization), depending on the heteregeneous phantom. Regarding the diffuse illumination, relative errors of -39.40%, -11.70%, 10.70%, and 10.60% are obtained for the 6 year-old boy, 11 year-old girl, 26 year-old female, and 34 year-old male, respectively. The proposed formula estimates well (especially for adults) the SARwb induced by diffuse illumination in realistic conditions. In general, the correctness of the formula improves when the human mass increases. Keeping the uncertainties of the FDTD simulations in mind, the proposed formula might be important for the dosimetry community to assess rapidly and accurately the human absorption of electromagnetic radiation caused by diffuse <span class="hlt">fields</span> in the GHz <span class="hlt">region</span>. Finally, we show the applicability of the proposed formula to personal dosimetry for epidemiological research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.8942E..0TQ&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.8942E..0TQ&link_type=ABSTRACT"><span id="translatedtitle">Large <span class="hlt">field</span>-of-view and depth-specific cortical microvascular imaging underlies <span class="hlt">regional</span> differences in ischemic brain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qin, Jia; Shi, Lei; Dziennis, Suzan; Wang, Ruikang K.</p> <p>2014-02-01</p> <p>Ability to non-invasively monitor and quantify of blood flow, blood vessel morphology, oxygenation and tissue morphology is important for improved diagnosis, treatment and management of various neurovascular disorders, e.g., stroke. Currently, no imaging technique is available that can satisfactorily extract these parameters from in vivo microcirculatory tissue beds, with large <span class="hlt">field</span> of view and sufficient resolution at defined depth without any harm to the tissue. In order for more effective therapeutics, we need to determine the area of brain that is damaged but not yet dead after focal ischemia. Here we develop an integrated multi-functional imaging system, in which SDW-LSCI (synchronized dual wavelength laser speckle imaging) is used as a guiding tool for OMAG (optical microangiography) to investigate the fine detail of tissue hemodynamics, such as vessel flow, profile, and flow direction. We determine the utility of the integrated system for serial monitoring afore mentioned parameters in experimental stroke, middle cerebral artery occlusion (MCAO) in mice. For 90 min MCAO, onsite and 24 hours following reperfusion, we use SDW-LSCI to determine distinct flow and oxygenation variations for differentiation of the infarction, peri-infarct, reduced flow and contralateral <span class="hlt">regions</span>. The blood volumes are quantifiable and distinct in afore mentioned <span class="hlt">regions</span>. We also demonstrate the behaviors of flow and flow direction in the arterials connected to MCA play important role in the time course of MCAO. These achievements may improve our understanding of vascular involvement under pathologic and physiological conditions, and ultimately facilitate clinical diagnosis, monitoring and therapeutic interventions of neurovascular diseases, such as ischemic stroke.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/29005','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/29005"><span id="translatedtitle">Source <span class="hlt">regions</span> of long-period pulsation events in electron precipitation and magnetic <span class="hlt">fields</span> at South Pole Station</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Paquette, J.A.; Matthews, D.L.; Rosenberg, T.J.; Lanzerotti, L.J.; Inan, U.S.</p> <p>1994-03-01</p> <p>Pulsation events with long (100-1000 s) periods with a consistent frequency in both particle precipitation and surface geomagnetic <span class="hlt">field</span> variations have been reported in the past from measurements made at various geomagnetic latitudes. An examination of broad beam riometer and magnetometer data from South Pole Station for the interval from 1982 to 1989 revealed nearly 200 such events. The onset times of these events were determined. This mechanism ascribes the occurrence of correlated magnetic and precipitation pulsations to ULF modulation of equatorial VLF wave-particle interactions. For this reason, VLF data from South Pole Station were also examined. Taking into consideration the ULF wave and particle transit times from an interaction <span class="hlt">region</span> near the magnetic equator to the ground leads to an expectation that the onset of pulsations in the magnetometer data will lag the onset of pulsations in the riometer data by several minutes. This disparity in onset times, together with modulation of VLF emissions in the 0.5-1 kHz band, serves as an important indicator of whether or not an event can be explained by the above-cited theory. While about a third of the events fit the prediction of Coroniti and Kennel, another third do not. In these events, the onset of magnetic and precipitation pulsations is nearly simultaneous, and possible alternative generation mechanisms are explored. In the remaining third of the events, magnetic pulsations begin substantially earlier than precipitation pulsations. Events of this type appear at first to be inexplicable in terms of any transit time argument. However, data from the imaging riometer at South Pole Station indicate that this third class of events is probably not physically distinct from the first two but is the result of the differing areas to which the riometer and magnetometer are sensitive and can be accounted for by considering the effects of transverse motion of a persistent precipitation <span class="hlt">region</span>. 24 refs., 13 rigs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhDT.......186S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhDT.......186S"><span id="translatedtitle">Extending a <span class="hlt">field</span>-based Sonoran desert vegetation classification to a <span class="hlt">regional</span> scale using optical and microwave satellite imagery</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shupe, Scott Marshall</p> <p>2000-10-01</p> <p>Vegetation mapping in and <span class="hlt">regions</span> facilitates ecological studies, land management, and provides a record to which future land changes can be compared. Accurate and representative mapping of desert vegetation requires a sound <span class="hlt">field</span> sampling program and a methodology to transform the data collected into a representative classification system. Time and cost constraints require that a remote sensing approach be used if such a classification system is to be applied on a <span class="hlt">regional</span> scale. However, desert vegetation may be sparse and thus difficult to sense at typical satellite resolutions, especially given the problem of soil reflectance. This study was designed to address these concerns by conducting vegetation mapping research using <span class="hlt">field</span> and satellite data from the US Army Yuma Proving Ground (USYPG) in Southwest Arizona. Line and belt transect data from the Army's Land Condition Trend Analysis (LCTA) Program were transformed into relative cover and relative density classification schemes using cluster analysis. Ordination analysis of the same data produced two and three-dimensional graphs on which the homogeneity of each vegetation class could be examined. It was found that the use of correspondence analysis (CA), detrended correspondence analysis (DCA), and non-metric multidimensional scaling (NMS) ordination methods was superior to the use of any single ordination method for helping to clarify between-class and within-class relationships in vegetation composition. Analysis of these between-class and within-class relationships were of key importance in examining how well relative cover and relative density schemes characterize the USYPG vegetation. Using these two classification schemes as reference data, maximum likelihood and artificial neural net classifications were then performed on a coregistered dataset consisting of a summer Landsat Thematic Mapper (TM) image, one spring and one summer ERS-1 microwave image, and elevation, slope, and aspect layers</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995mpls.workQ....G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995mpls.workQ....G"><span id="translatedtitle">Mars Pathfinder Landing Site Workshop II: Characteristics of the Ares Vallis <span class="hlt">Region</span> and <span class="hlt">Field</span> Trips in the Channeled Scabland, Washington</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Golombek, M. P.; Edgett, K. S.; Rice, J. W., Jr.</p> <p>1995-09-01</p> <p>This volume, the first of two comprising the technical report for this workshop, contains papers that have been accepted for presentation at the Mars Pathfinder Landing Site Workshop 2 24-30, 1995, in Spokane, Washington. The Mars Pathfinder Project received a new start in October 1993 as one of the next missions in NASA's long-term Mars exploration program. The mission involves landing a single vehicle on the surface of Mars in 1997. The project is one of the first Discovery-class missions and is required to be a quick, low-cost mission and achieve a set of significant but focused engineering, science, and technology objectives. The primary objective is to demonstrate a low-cost cruise, entry, descent, and landing system required to place a payload on the martian surface in a safe, operational configuration. Additional objectives include the deployment and operation of various science instruments and a microrover. Pathfinder paves the way for a cost-effective implementation of future Mars lander missions. Also included in this volume is the <span class="hlt">field</span> trip guide to the Channeled Scabland and Missoula Lake Break-out. On July 4, 1997, Mars Pathfinder is scheduled to land near 19.5 deg N, 32.8 deg W, in a portion of Ares Vallis. The landing ellipse covers a huge (100 x 200 km) area that appears to include both depositional and erosional landforms created by one or more giant, catastrophic floods. One of the best known terrestrial analogs to martian outflow channels (such as Ares Vallis) is the <span class="hlt">region</span> known as the Channeled Scabland. The <span class="hlt">field</span> trip guide describes some of the geomorphological features of the Channeled Scabland and adjacent Lake Missoula break-out area near Lake Pend Oreille, Idaho.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.B13G0589M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.B13G0589M"><span id="translatedtitle">Towards integrating the influence of erosion on within <span class="hlt">field</span> variability of C input, stock and stability in <span class="hlt">regional</span> SOC estimates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meersmans, J.; Quine, T. A.</p> <p>2013-12-01</p> <p> approach allows us to unravel the influence of lateral transport processes (erosion) on the within <span class="hlt">field</span> vertical heterogeneity in SOC stock and stability and associated variation in C input, and hence can be considered as a first step to refine spatial-temporal mapping of SOC at <span class="hlt">regional</span> scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003SPD....34.1615L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003SPD....34.1615L"><span id="translatedtitle">Photospheric Magnetic <span class="hlt">Field</span> Properties of Flaring vs. Flare-Quiet Active <span class="hlt">Regions</span> I: Data, General Approach, and Statistical Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leka, K. D.; Barnes, G.</p> <p>2003-05-01</p> <p>Photospheric vector magnetic <span class="hlt">field</span> data from the U. Hawai`i Imaging Vector Magnetograph are examined for pre-event signatures unique to solar energetic phenomena. Parameters are constructed from B(x,y) to describe (for example) the distributions of the <span class="hlt">field</span>, spatial gradients of the <span class="hlt">field</span>, vertical current, current helicity, ''twist'' parameter α and magnetic shear angles. A quantitative statistical approach employing discriminant analysis and Hotelling's T2-test is applied to the magnitude and temporal evolution of parameters from 24 flare-event and flare-quiet epochs from seven active <span class="hlt">regions</span>. We demonstrate that (1) when requiring a flare-unique signature, numerous candidate parameters are nullified by considering flare-quiet epochs, (2) a more robust method exists for estimating error rates than conventional ''truth tables'', (3) flaring and flare-quiet populations do not necessarily have low error rates for classification even when statistically distinguishable, and that (4) simultaneous consideration of a large number of variables is required to produce acceptable error rates. That is, when the parameters are considered individually, they show little ability to differentiate between the two populations; multi-variable combinations can discriminate the populations and/or result in perfect classification tables. In lieu of constructing a single all-variable discriminant function to quantify the flare-predictive power of the parameters considered, we devise a method whereby all permutations of the four-variable discriminant functions are ranked by Hotelling's T2. We present those parameters (e.g. the temporal increase of the kurtosis of the spatial distribution of the vertical current density) which consistently appear in the best combinations, indicating that they may play an important role in defining a pre-event photospheric state. While no single combination is clearly the best discriminator, we demonstrate here the requisite approach: include flare</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3260647','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3260647"><span id="translatedtitle"><span class="hlt">Field</span> Performance of Nine Soil Water Content Sensors on a Sandy Loam Soil in New Brunswick, Maritime <span class="hlt">Region</span>, Canada</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chow, Lien; Xing, Zisheng; Rees, Herb W.; Meng, Fanrui; Monteith, John; Stevens, Lionel</p> <p>2009-01-01</p> <p>An in situ <span class="hlt">field</span> test on nine commonly-used soil water sensors was carried out in a sandy loam soil located in the Potato Research Center, Fredericton, NB (Canada) using the gravimetric method as a reference. The results showed that among the tested sensors, regardless of installation depths and soil water regimes, CS615, Trase, and Troxler performed the best with the factory calibrations, with a relative root mean square error (RRMSE) of 15.78, 16.93, and 17.65%, and a r2 of 0.75, 0.77, and 0.65, respectively. TRIME, Moisture Point (MP917), and Gopher performed slightly worse with the factory calibrations, with a RRMSE of 45.76, 26.57, and 20.41%, and a r2 of 0.65, 0.72, and 0.78, respectively, while the Gypsum, WaterMark, and Netafim showed a frequent need for calibration in the application in this <span class="hlt">region</span>. PMID:22291570</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JGRA..114.1301P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JGRA..114.1301P"><span id="translatedtitle">Planetary-scale variability in the low-latitude E <span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities: First results from Gadanki observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Phanikumar, D. V.; Patra, A. K.; Ratnam, M. V.; Sripathi, S.</p> <p>2009-01-01</p> <p>In this paper, we present for the first time planetary-scale wave signatures in the low-latitude E <span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities (FAI) observed during June 2004 to May 2005 using the Gadanki mesosphere-stratosphere-troposphere radar. We have observed a clear signature of 5-8 day variability in echo occurrence, in SNR, and also in Doppler velocity observed above 100 km. Concurrent temperature observations made using the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) on board the Thermosphere-Ionosphere-Mesosphere Energetic and Dynamics (TIMED) satellite have also clearly shown the presence of 5-8 day variability similar to that of FAI. The temperature variations have been characterized with zonal wave numbers of 3 and 4 and vertical wavelength of 15-20 km. These waves are found to have increasing amplitude with increasing height and phase progressing downward, suggesting that they were of lower atmospheric origin. It is emphasized that the planetary-scale characteristics of neutral atmosphere in the FAI observations are important in understanding the vertical coupling of the low-latitude ionosphere-atmosphere system. These observations and the pertinent issues are discussed in the light of current understanding of the planetary-scale role on the FAI variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25709379','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25709379"><span id="translatedtitle">Far <span class="hlt">field</span> R-wave sensing in Myotonic Dystrophy type 1: right atrial appendage versus Bachmann's bundle <span class="hlt">region</span> lead placement.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Russo, Vincenzo; Nigro, Gerardo; Antonio Papa, Andrea; Rago, Anna; Di Meo, Federica; Cristiano, Anna; Molino, Antonio; Calabrò, Raffaele; Giovanna Russo, Maria; Politano, Luisa</p> <p>2014-10-01</p> <p>Aim of the present study was to investigate far <span class="hlt">field</span> R-wave sensing (FFRS) timing and characteristics in 34 Myotonic Dystrophy type 1 (DM1) patients undergoing dual chamber pacemaker implantation, comparing Bachmann's bundle (BB) stimulation (16 patients) site with the conventional right atrial appendage (RAA) pacing site (18 patients). All measurements were done during sinus rhythm and in supine position, with unipolar (UP) and bipolar (BP) sensing configuration. The presence, amplitude threshold (FFRS trsh) and FFRS timing were determined. There were no differences between both atrial sites in the Pmin and Pmean values of sensed P-wave amplitudes, as well as between UP and BP sensing configurations. The FFRS trsh was lower at the BB <span class="hlt">region</span> in comparison to the RAA site. The mean BP FFRS trsh was significantly lower than UP configuration in both atrial locations. There were no significant differences in atrial pacing threshold, sensing threshold and atrial lead impedances at the implant time and at FFRS measurements. Bachmann's bundle area is an optimal atrial lead position for signal sensing as well as conventional RAA, but it offers the advantage of reducing the oversensing of R-wave on the atrial lead, thus improving functioning of standard dual chamber pacemakers in DM1 patients. PMID:25709379</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740060904&hterms=dipole+magnetic&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Ddipole%2Bmagnetic','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740060904&hterms=dipole+magnetic&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Ddipole%2Bmagnetic"><span id="translatedtitle">The protons and electrons trapped in the Jovian dipole magnetic <span class="hlt">field</span> <span class="hlt">region</span> and their interaction with Io</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Simpson, J. A.; Hamilton, D. C.; Mckibben, R. B.; Mogro-Campero, A.; Pyle, K. R.; Tuzzolino, A. J.</p> <p>1974-01-01</p> <p>Detailed analysis of electrons equal to or greater than 3 MeV and of protons 0.5 to 1.8 MeV and equal to or greater than 35 MeV for both the inbound and the outbound passes of the Pioneer 10 spacecraft. Conclusive evidence is obtained that the trapped radiation in Jupiter's inner magnetosphere is maintained and supplied by inward diffusion from the outer <span class="hlt">regions</span> of the trapped radiation zone. It is shown that the time required for isotropization of an anisotropic flux by pitch angle scattering inside L approximately equal to 6 is long in comparison with the time required for particles to diffuse inward from L approximately equal to 6 to L approximately equal to 3, that the high-energy protons were not injected at high energies by the Crand (cosmic ray albedo neutron decay) process but were accelerated in the magnetosphere of Jupiter, and that the main conclusions of this analysis are unaffected by use of either the D sub 1 or the D sub 2 magnetic <span class="hlt">field</span> models. Theoretical studies of the capture of trapped electrons and protons by Io have been carried out, and it is found that the probability of capture by Io depends strongly upon the particle species and kinetic energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25635864','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25635864"><span id="translatedtitle">In situ nitrogen mineralization, nitrification, and ammonia volatilization in maize <span class="hlt">field</span> fertilized with urea in Huanghuaihai <span class="hlt">region</span> of northern China.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Xuelin; Wang, Qun; Xu, Jun; Gilliam, Frank S; Tremblay, Nicolas; Li, Chaohai</p> <p>2015-01-01</p> <p>Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH3 volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha(-1)) was performed in 2009 and 2010 in a maize <span class="hlt">field</span> in Huanghuaihai <span class="hlt">region</span>, China, where > 300 kg N ha(-1) has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0-10 cm), NH3 volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization and nitrification varied seasonally, with higher rates occurring in August and coinciding with the R1 stage of maize growth. Soil NO3(-)-N contributed to more than 60% of inorganic N flux during maize growth. Cumulative NH3 volatilization increased with N additions, with total NH3 volatilization during maize growth accounting for about 4% of added N. Relative to the control, mean maize yield in the fertilizer treatments increased by 17% and 20% in 2009 and 2010, respectively. However, grain yield, aboveground biomass, and plant N accumulation did not increase with added N at levels > 215 kg N ha(-1). These results suggest that the current N rate of 300 kg N ha(-1) is not only excessive, but also reduces fertilizer efficacy and may contribute to environmental problems such as global warming and eutrophication of ground water and streams. PMID:25635864</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040182462&hterms=satellite+gravity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D30%26Ntt%3Dsatellite%2Bgravity','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040182462&hterms=satellite+gravity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D30%26Ntt%3Dsatellite%2Bgravity"><span id="translatedtitle">Contribution to the Study of <span class="hlt">Regional</span> Magnetization of Satellite Magnetic Measurement: Magsat, Orsted, and Champ (with Gravity <span class="hlt">Field</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Taylor, Patrick T.</p> <p>2004-01-01</p> <p>A discussion of and introduction to satellite-altitude geopotential <span class="hlt">field</span> studies and their interpretation with emphasis on results from metalliferous <span class="hlt">regions</span> will be given. The magnetic and gravimetric measurements from satellite altitudes show heterogeneity in deeper parts of the lithosphere. These patterns of magnetic anomalies do not only reveal the largest iron ore deposits such as Kiruna, Sweden, Kursk, Russia, and Banugi, Central African Republic but also linear features indicating structural discontinuities. Changes of magnetic amplitude of these patterns are caused by intersecting transverse fractures localizing magmatism and concentration of metals. In addition satellite altitude data are related to variations in crustal thickness and heat flow. Deep-rooted structural discontinuities, defined by combination of geological and geophysical criteria, with spacing of several hundred kilometers, reveal a quite uniform pattern in the deeper parts of the lithosphere. As these structures provide favorable pathways for the ascent of heat, magmas and ore-forming fluids, their recognition is of crucial importance and can be used in the compilation of a new type of mineral prognosis map. An example from Europe includes a pattern of east west trending structural discontinuities or belts and their junction with the NW-trending Tornqvist-Teisseyre Line. The Upper Silesian-Cracovian Zn-Pb district occurs along one of the latitudinal belts. Leslaw Teper of the University of Silesia has been invited to show the fractures in crystalline basement beneath the sediments hosting the Zn-Pb ores.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRD..11221109K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRD..11221109K"><span id="translatedtitle">Dust mobilization due to density currents in the Atlas <span class="hlt">region</span>: Observations from the Saharan Mineral Dust Experiment 2006 <span class="hlt">field</span> campaign</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knippertz, P.; Deutscher, C.; Kandler, K.; Müller, T.; Schulz, O.; Schütz, L.</p> <p>2007-11-01</p> <p>Evaporation of precipitation is a ubiquitous feature of dry and hot desert environments. The resulting cooling often generates density currents with strong turbulent winds along their leading edges, which can mobilize large amounts of dust. Mountains support this process by triggering convection, by downslope acceleration of the cool air, and by fostering the accumulation of fine-grained sediments along their foothills through the action of water. For the Sahara, the world's largest dust source, this mechanism has been little studied because of the lack of sufficiently high resolution observational data. The present study demonstrates the frequent occurrence of density currents along the Sahara side of the Atlas Mountain chain in southern Morocco using the unique data set collected during the Saharan Mineral Dust Experiment (SAMUM) <span class="hlt">field</span> campaign in May/June 2006. The density currents are related to convection over the mountains in the afternoon hours and have lifetimes on the order of 10 h. The passage of the sharp leading edge that sometimes reaches several hundred kilometers in length is usually associated with a marked increase in dew point and wind speed, a change in wind direction, and a decrease in temperature and visibility due to suspended dust. It is conceivable that this mechanism is relevant for other mountainous <span class="hlt">regions</span> in northern Africa during the warm season. This would imply that simulations of the dust cycle with numerical models need a reliable representation of moist convective processes in order to generate realistic dust emissions from the Sahara.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4311962','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4311962"><span id="translatedtitle">In Situ Nitrogen Mineralization, Nitrification, and Ammonia Volatilization in Maize <span class="hlt">Field</span> Fertilized with Urea in Huanghuaihai <span class="hlt">Region</span> of Northern China</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhang, Xuelin; Wang, Qun; Xu, Jun; Gilliam, Frank S.; Tremblay, Nicolas; Li, Chaohai</p> <p>2015-01-01</p> <p>Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH3 volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha-1) was performed in 2009 and 2010 in a maize <span class="hlt">field</span> in Huanghuaihai <span class="hlt">region</span>, China, where > 300 kg N ha-1 has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0–10cm), NH3 volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization and nitrification varied seasonally, with higher rates occurring in August and coinciding with the R1 stage of maize growth. Soil NO3−-N contributed to more than 60% of inorganic N flux during maize growth. Cumulative NH3 volatilization increased with N additions, with total NH3 volatilization during maize growth accounting for about 4% of added N. Relative to the control, mean maize yield in the fertilizer treatments increased by 17% and 20% in 2009 and 2010, respectively. However, grain yield, aboveground biomass, and plant N accumulation did not increase with added N at levels > 215 kg N ha-1. These results suggest that the current N rate of 300 kg N ha-1 is not only excessive, but also reduces fertilizer efficacy and may contribute to environmental problems such as global warming and eutrophication of ground water and streams. PMID:25635864</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22291570','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22291570"><span id="translatedtitle"><span class="hlt">Field</span> performance of nine soil water content sensors on a sandy loam soil in new brunswick, maritime <span class="hlt">region</span>, Canada.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chow, Lien; Xing, Zisheng; Rees, Herb W; Meng, Fanrui; Monteith, John; Stevens, Lionel</p> <p>2009-01-01</p> <p>An in situ <span class="hlt">field</span> test on nine commonly-used soil water sensors was carried out in a sandy loam soil located in the Potato Research Center, Fredericton, NB (Canada) using the gravimetric method as a reference. The results showed that among the tested sensors, regardless of installation depths and soil water regimes, CS615, Trase, and Troxler performed the best with the factory calibrations, with a relative root mean square error (RRMSE) of 15.78, 16.93, and 17.65%, and a r(2) of 0.75, 0.77, and 0.65, respectively. TRIME, Moisture Point (MP917), and Gopher performed slightly worse with the factory calibrations, with a RRMSE of 45.76, 26.57, and 20.41%, and a r(2) of 0.65, 0.72, and 0.78, respectively, while the Gypsum, WaterMark, and Netafim showed a frequent need for calibration in the application in this <span class="hlt">region</span>. PMID:22291570</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24772676','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24772676"><span id="translatedtitle">Ground ultra-low volume adulticiding <span class="hlt">field</span> trials using pyrethroids against Aedes albopictus in the Baix Llobregat <span class="hlt">region</span>, Spain.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bengoa, Mikel; Eritja, Roger; Lucientes, Javier</p> <p>2014-03-01</p> <p>Ground ultra-low volume (ULV) application against Aedes albopictus is a challenging methodology as its efficacy is strongly related to environmental conditions, insect behavior, and the pesticide formulation. Such operations are very relevant in many control programs, although their real efficacy is often unknown. Trials were carried out as part of real-world applications in urban scenarios in the Baix Llobregat <span class="hlt">region</span> to evaluate the efficacy of 2 active ingredients, delatamethrin and alpha-cypermethrin. Both pyrethroids were tested against caged mosquitoes placed at a range of distances and under varying environmental conditions. Additionally, persistence on plants placed at the same distances was evaluated after 5 h, as well as droplet distribution using water-sensitive papers. The deltamethrin formulation used yielded significantly higher 24-h mortality than alpha-cypermethrin (100% direct mortality up to 25 m versus 10 m; and 73.9% residual 5-h mortality at 20 m compared to <50% at 5 m). The influence of environmental factors, a comparison with other <span class="hlt">field</span> tests, and the real effect on uncaged mosquitoes is discussed. PMID:24772676</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12786507','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12786507"><span id="translatedtitle">Matrix formalism of electromagnetic wave propagation through multiple layers in the near-<span class="hlt">field</span> <span class="hlt">region</span>: application to the flat panel display.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, C Y; Lee, D E; Hong, Y K; Shim, J H; Jeong, C K; Joo, J; Zang, D S; Shim, M G; Lee, J J; Cha, J K; Yang, H G</p> <p>2003-04-01</p> <p>We have developed an electromagnetic (EM) wave propagation theory through a single layer and multiple layers in the near-<span class="hlt">field</span> and far-<span class="hlt">field</span> <span class="hlt">regions</span>, and have constructed a matrix formalism in terms of the boundary conditions of the EM waves. From the shielding efficiency (SE) against EM radiation in the near-<span class="hlt">field</span> <span class="hlt">region</span> calculated by using the matrix formalism, we propose that the effect of multiple layers yields enhanced shielding capability compared to a single layer with the same total thickness in conducting layers as the multiple layers. We compare the intensities of an EM wave propagating through glass coated with conducting indium tin oxide (ITO) on one side and on both sides, applying it to the electromagnetic interference (EMI) shielding filter in a flat panel display such as a plasma display panel (PDP). From the measured intensities of EMI noise generated by a PDP loaded with ITO coated glass samples, the two-side coated glass shows a lower intensity of EMI noise compared to the one-side coated glass. The result confirms the enhancement of the SE due to the effect of multiple layers, as expected in the matrix formalism of EM wave propagation in the near-<span class="hlt">field</span> <span class="hlt">region</span>. In the far-<span class="hlt">field</span> <span class="hlt">region</span>, the two-side coated glass with ITO in multiple layers has a higher SE than the one-side coated glass with ITO, when the total thickness of ITO in both cases is the same. PMID:12786507</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cancer.gov/espanol/cancer/causas-prevencion/riesgo/hoja-informativa-estudio-salud-agricola','NCI'); return false;" href="https://www.cancer.gov/espanol/cancer/causas-prevencion/riesgo/hoja-informativa-estudio-salud-agricola"><span id="translatedtitle"><span class="hlt">Estudio</span> de Salud Agrícola</span></a></p> <p><a target="_blank" href="http://www.cancer.gov">Cancer.gov</a></p> <p></p> <p></p> <p>En 1993, científicos del Instituto Nacional del Cáncer, Instituto Nacional de Ciencias Ambientales y la Agencia de Protección Ambiental de Estados Unidos iniciaron un <span class="hlt">estudio</span> conocido como <span class="hlt">Estudio</span> de Salud Agrícola (AHS).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1615521K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1615521K"><span id="translatedtitle">Structure function analysis of changes found in the ELF electric <span class="hlt">field</span> prior to the strong earthquakes and in other highly perturbed <span class="hlt">regions</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kosciesza, Malgorzata; Blecki, Jan; Wronowski, Roman; Parrot, Michel</p> <p>2014-05-01</p> <p>We report the structure function analysis of changes found in electric <span class="hlt">field</span> in the ELF range plasma turbulence registered by the DEMETER satellite in the ionosphere over epicenter <span class="hlt">region</span> of three earthquakes. First one took place on 16th of December 2006 in Ping Tong <span class="hlt">Region</span> with magnitude 7.1. Second was earthquake with magnitude 6.3 in L'Aquila on 6th April 2009. The last one took place on 27th of February 2010 in Offshore of Chile with magnitude 8.8. The structure functions were calculated also for the Polar CUSP <span class="hlt">region</span> and equatorial spread F <span class="hlt">region</span>. Basic studies of the turbulent processes were conducted with use of higher order spectra and higher order statistics. The structure function analysis was performed to locate and check if there are intermittent behaviors in the ionospheres plasma over epicenter <span class="hlt">region</span> of the earthquakes. These registrations are correlated with the plasma parameters measured onboard DEMETER satellite and with geomagnetic indices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7016982','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/7016982"><span id="translatedtitle">Direct/Delayed Response Project: <span class="hlt">Field</span> operations and quality-assurance report for watershed mapping in the Mid-Appalachian <span class="hlt">region</span> of the United States</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kern, J.S.; Lammers, D.A.; Cassell, D.L.; Campbell, W.G.</p> <p>1990-05-01</p> <p>The report documents the mapping program of the Direct/Delayed Response Project in the Mid-Appalachian <span class="hlt">Region</span> of the United States. The objectives of the report is to document the planning activities, <span class="hlt">field</span> operations, and quality assurance/quality control (QA/QC) of the mapping. The protocols, QA plan, and soil legend for the watershed mapping are presented as appendices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=17079&keyword=trade+AND+electronic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=76328212&CFTOKEN=66927556','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=17079&keyword=trade+AND+electronic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=76328212&CFTOKEN=66927556"><span id="translatedtitle">NHEXAS PHASE I <span class="hlt">REGION</span> 5 STUDY--STANDARD OPERATING PROCEDURE--SAMPLE CODING, LABELING, AND <span class="hlt">FIELD</span> TRACKING PROCEDURES (RTI/ACS-AP-209-070)</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This protocol defines the coding scheme, labeling procedures, and <span class="hlt">field</span> tracking for samples collected in the NHEXAS <span class="hlt">Region</span> 5 study. Unique sample codes were assigned to all personal, environmental, biological, and quality control samples. A label bearing the code in both bar cod...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989GeCoA..53.2683N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989GeCoA..53.2683N"><span id="translatedtitle">Strontium isotope constraint on the genesis of crude oils, oil-<span class="hlt">field</span> brines and Kuroko ore deposits from the Green Tuff <span class="hlt">region</span> of northeastern Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakano, Takanori; Kajiwara, Yoshimichi; Farrell, Clifton W.</p> <p>1989-10-01</p> <p>Crude oils from Akita to northern Niigata oil <span class="hlt">fields</span> in the Green Tuff <span class="hlt">region</span> of northeastern Japan have distinctly uniform 87Sr/86Sr ratios (0.7080-0.7082), while those from the southern Niigata oil <span class="hlt">field</span> contain more radiogenic strontium (0.7095-0.7102). The <span class="hlt">regional</span> variation in the strontium isotopic composition of crude oils is also reflected in their sulfur contents and sulfur isotopic compositions, and may be attributed to the <span class="hlt">regional</span> heterogeneity of marine organic sediments from which the crude oils were ultimately derived. The 87Sr/86Sr ratios of most oil-<span class="hlt">field</span> brines (0.7061-0.7084), however, are different from and vary more locally than those of the accompanying crude oils. This finding supports the view that strontium, and by inference some other dissolved solutes in the brines, may have evolved during diagenesis by reaction of a connate and/or a meteoric water with rocks in the Green Tuff <span class="hlt">region</span>. Barites in the sulfide ore and anhydrites and gypsums in the sulfate (sekko) ore from the Fukazawa and Kosaka Kuroko deposits in the Hokuroku district are divided by the 87Sr/86Sr ratio of 0.7081 (±0.0001), which is identical to that of crude oils from nearby oil <span class="hlt">fields</span>. This similarity in ratios lends support to the conclusion that the Kuroko base metal deposits and crude oil deposits were ultimately derived from a common organic sediment named PUMOS (Primitive Undifferentiated Metalliferous Organic Sediments).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1614275E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1614275E"><span id="translatedtitle"><span class="hlt">Regional</span> gravity <span class="hlt">field</span> modeling using radial basis functions: results from IAG's Joint Study Group JSG0.3 and real data GOCE applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eicker, Annette; Schall, Judith; Lieb, Verena; Bentel, Katrin; Schmidt, Michael; Buße, Kirsten; Kusche, Jürgen; Gerlach, Christian</p> <p>2014-05-01</p> <p>Traditionally, the gravity <span class="hlt">field</span> of the Earth is modeled as a series expansion into globally defined spherical harmonic basis functions. However, it is well-known that spherical harmonic approaches have problems to properly represent data of heterogeneous density and quality. These and other deficiencies can be overcome using <span class="hlt">regional</span> modeling approaches, which allow to more flexibly adjust the analysis procedure to the gravity <span class="hlt">field</span> signal in certain geographical areas. Therefore, different sophisticated <span class="hlt">regional</span> gravity <span class="hlt">field</span> modeling approaches have been developed in recent years. In order to systematically compare the different approaches, the IAG ICCT Joint Study Group JSG0.3 "Comparison of Current Methodologies in <span class="hlt">Regional</span> Gravity <span class="hlt">Field</span> Modeling" has recently created synthetic test data sets. In this presentation we will discuss and compare the results obtained from the test data sets using a parameterization by different types of radial basis functions as provided by the groups of the University of Bonn, the German Geodetic Research Institute (DGFI) and the Norwegian University of Life Sciences. Furthermore, we will present the improvements that can be obtained by <span class="hlt">regional</span> processing techniques compared to global spherical harmonic modeling at the example of GOCE real data applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70036491','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70036491"><span id="translatedtitle">Geology, geochronology, and paleogeography of the southern Sonoma volcanic <span class="hlt">field</span> and adjacent areas, northern San Francisco Bay <span class="hlt">region</span>, California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wagner, D.L.; Saucedo, G.J.; Clahan, K.B.; Fleck, R.J.; Langenheim, V.E.; McLaughlin, R.J.; Sarna-Wojcicki, A. M.; Allen, J.R.; Deino, A.L.</p> <p>2011-01-01</p> <p>Recent geologic mapping in the northern San Francisco Bay <span class="hlt">region</span> (California, USA) supported by radiometric dating and tephrochronologic correlations, provides insights into the framework geology, stratigraphy, tectonic evolution, and geologic history of this part of the San Andreas transform plate boundary. There are 25 new and existing radiometric dates that define three temporally distinct volcanic packages along the north margin of San Pablo Bay, i.e., the Burdell Mountain Volcanics (11.1 Ma), the Tolay Volcanics (ca. 10-8 Ma), and the Sonoma Volcanics (ca. 8-2.5 Ma). The Burdell Mountain and the Tolay Volcanics are allochthonous, having been displaced from the Quien Sabe Volcanics and the Berkeley Hills Volcanics, respectively. Two samples from a core of the Tolay Volcanics taken from the Murphy #1 well in the Petaluma oilfield yielded ages of 8.99 ?? 0.06 and 9.13 ?? 0.06 Ma, demonstrating that volcanic rocks exposed along Tolay Creek near Sears Point previously thought to be a separate unit, the Donnell Ranch volcanics, are part of the Tolay Volcanics. Other new dates reported herein show that volcanic rocks in the Meacham Hill area and extending southwest to the Burdell Mountain fault are also part of the Tolay Volcanics. In the Sonoma volcanic <span class="hlt">field</span>, strongly bimodal volcanic sequences are intercalated with sediments. In the Mayacmas Mountains a belt of eruptive centers youngs to the north. The youngest of these volcanic centers at Sugarloaf Ridge, which lithologically, chemically, and temporally matches the Napa Valley eruptive center, was apparently displaced 30 km to the northwest by movement along the Carneros and West Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the RodgersCreek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek-Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa basin in the Late Miocene and was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SoPh..287..239W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SoPh..287..239W"><span id="translatedtitle">Comparing Simulations of Rising Flux Tubes Through the Solar Convection Zone with Observations of Solar Active <span class="hlt">Regions</span>: Constraining the Dynamo <span class="hlt">Field</span> Strength</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weber, M. A.; Fan, Y.; Miesch, M. S.</p> <p>2013-10-01</p> <p>We study how active-<span class="hlt">region</span>-scale flux tubes rise buoyantly from the base of the convection zone to near the solar surface by embedding a thin flux tube model in a rotating spherical shell of solar-like turbulent convection. These toroidal flux tubes that we simulate range in magnetic <span class="hlt">field</span> strength from 15 kG to 100 kG at initial latitudes of 1∘ to 40∘ in both hemispheres. This article expands upon Weber, Fan, and Miesch ( Astrophys. J. 741, 11, 2011) (Article 1) with the inclusion of tubes with magnetic flux of 1020 Mx and 1021 Mx, and more simulations of the previously investigated case of 1022 Mx, sampling more convective flows than the previous article, greatly improving statistics. Observed properties of active <span class="hlt">regions</span> are compared to properties of the simulated emerging flux tubes, including: the tilt of active <span class="hlt">regions</span> in accordance with Joy's Law as in Article 1, and in addition the scatter of tilt angles about the Joy's Law trend, the most commonly occurring tilt angle, the rotation rate of the emerging loops with respect to the surrounding plasma, and the nature of the magnetic <span class="hlt">field</span> at the flux tube apex. We discuss how these diagnostic properties constrain the initial <span class="hlt">field</span> strength of the active-<span class="hlt">region</span> flux tubes at the bottom of the solar convection zone, and suggest that flux tubes of initial magnetic <span class="hlt">field</span> strengths of ≥ 40 kG are good candidates for the progenitors of large (1021 Mx to 1022 Mx) solar active <span class="hlt">regions</span>, which agrees with the results from Article 1 for flux tubes of 1022 Mx. With the addition of more magnetic flux values and more simulations, we find that for all magnetic <span class="hlt">field</span> strengths, the emerging tubes show a positive Joy's Law trend, and that this trend does not show a statistically significant dependence on the magnetic flux.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5309286','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5309286"><span id="translatedtitle">Liquid-metal flow in a thin conducting pipe near the end of a <span class="hlt">region</span> of uniform magnetic <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Walker, J.S.</p> <p>1986-04-01</p> <p>This paper treats the liquid-metal flow in a straight circular pipe with a thin metal wall. A strong magnetic <span class="hlt">field</span> is applied by a magnet with parallel poles that end abruptly. In the plane midway between the magnet poles: (1) far upstream, the flow is uniform, fully developed flow in a uniform magnetic <span class="hlt">field</span>; (2) as the flow enters the non-uniform magnetic <span class="hlt">field</span> near the end of the magnet, the flow moves away from the central part of the pipe and becomes concentrated as two jets near the points where the magnetic <span class="hlt">field</span> is tangent to the pipe wall; (3) further downstream where the magnetic <span class="hlt">field</span> strength is 0(c/sup 1/6/) compared to its value upstream, the flow migrates from these jets back toward a uniform flow distributed over the entire pipe cross section. Here, c is the wall conductance ratio, which is assumed to be small. The analysis also applies to flow into the magnetic <span class="hlt">field</span>, because inertial effects and induced magnetic <span class="hlt">fields</span> are neglected. There are circulations of electric current in planes parallel to the magnet poles. These currents produce a pressure drop in addition to that for two fully developed flows, one in a uniform magnetic <span class="hlt">field</span> and one in no magnetic <span class="hlt">field</span>, joined at the end of the magnet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840012901','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840012901"><span id="translatedtitle">The Archean crust in the Wawa-Chapleau-Timmins <span class="hlt">region</span>. A <span class="hlt">field</span> guidebook prepared for the 1983 Archean Geochemistry-Early Crustal Genesis <span class="hlt">Field</span> Conference</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Percival, J. A.; Card, K. D.; Sage, R. P.; Jensen, L. S.; Luhta, L. E.</p> <p>1983-01-01</p> <p>This guidebook describes the characteristics and interrelationships of Archean greenstone-granite and high-grade gneiss terrains of the Superior Province. A 300-km long west to east transect between Wawa and Timmins, Ontario will be used to illustrate <span class="hlt">regional</span>-scale relationships. The major geological features of the Superior Province are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013AGUFMSA51A2054Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013AGUFMSA51A2054Y&link_type=ABSTRACT"><span id="translatedtitle">Statistical characteristics and occurrences of the F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities in middle latitudes observed with Korea VHF coherent scattering radar</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, T.; Kwak, Y.; Kil, H.; Park, Y.</p> <p>2013-12-01</p> <p>We report for the first time of the long term characteristics and percentage occurrences of F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities (FAIs) in the middle latitude observed with Korea VHF coherent scattering radar. This radar was built at Daejeon(36.18°N, 127.14°E, dip latitude 26.7°N) with 40.8 MHz operating frequency for continuous monitoring of the behavior of electron density irregularities in the middle latitude. From more than three-year of continuous observations since 2010, we have obtained the diurnal and seasonal characteristics of a signal-to-noise ratio and percentage occurrence variations from F-<span class="hlt">region</span> FAIs over Korea peninsular. F-<span class="hlt">region</span> FAIs appeared frequently at right after the sunset in both equinoxes, but pre- and post-midnight in summer season. F-<span class="hlt">region</span> irregularities are intensified after sunset to before sunrise, and then the occurrence of F-<span class="hlt">region</span> FAIs is rapidly decreased after sunrise. Peak height of F-<span class="hlt">region</span> irregularities have seen around 300 km altitudes in the evening, then at higher altitude up to 400 km near local midnight and then lower altitudes around 300 km again in the early morning. And also we found that the obtained F-<span class="hlt">region</span> echoes can be classified as E-<span class="hlt">region</span>'s continuous and quasi-periodic echoes, even though, the duration, occur time and locations are different from Kwak et al. (this issue).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=emilia+AND+ferreiro&id=ED292723','ERIC'); return false;" href="http://eric.ed.gov/?q=emilia+AND+ferreiro&id=ED292723"><span id="translatedtitle">The Major Project in the <span class="hlt">Field</span> of Education in the Latin American and Caribbean <span class="hlt">Region</span>. Bulletin #13.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.</p> <p></p> <p>This document addresses several of the problems of educational planning in Latin America. Emilia Ferreiro, in "Alternatives to Understanding Illiteracy in the <span class="hlt">Region</span>," suggests that illiteracy in this <span class="hlt">region</span> is preventing the attainment of democracy. As social inequality increases, so does the percentage of illiterate adults. Revolutionary social…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ACP....13.5655T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ACP....13.5655T"><span id="translatedtitle">Megacity impacts on <span class="hlt">regional</span> ozone formation: observations and WRF-Chem modeling for the MIRAGE-Shanghai <span class="hlt">field</span> campaign</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tie, X.; Geng, F.; Guenther, A.; Cao, J.; Greenberg, J.; Zhang, R.; Apel, E.; Li, G.; Weinheimer, A.; Chen, J.; Cai, C.</p> <p>2013-06-01</p> <p>The MIRAGE-Shanghai experiment was designed to characterize the factors controlling <span class="hlt">regional</span> air pollution near a Chinese megacity (Shanghai) and was conducted during September 2009. This paper provides information on the measurements conducted for this study. In order to have some deep analysis of the measurements, a <span class="hlt">regional</span> chemical/dynamical model (version 3 of Weather Research and Forecasting Chemical model - WRF-Chemv3) is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai <span class="hlt">region</span>, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability) of air pollutants in the Shanghai <span class="hlt">region</span>, and the differences between the model calculation and the measurement are mostly smaller than 30%, except the calculations of HONO (nitrous acid) at PD (Pudong) and CO (carbon monoxide) at DT (Dongtan). The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a <span class="hlt">regional</span> scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC (volatile organic compound)-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger <span class="hlt">regional</span> area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large <span class="hlt">regional</span> area in the surrounding <span class="hlt">region</span> of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx (nitric oxide and nitrogen dioxide)-limited condition. The threshold value is strongly dependent on the emission ratio of NOx / VOCs. When the ratio is about</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ACPD...13.1673T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ACPD...13.1673T"><span id="translatedtitle">Megacity impacts on <span class="hlt">regional</span> ozone formation: observations and WRF-Chem modeling for the MIRAGE-Shanghai <span class="hlt">field</span> campaign</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tie, X.; Geng, F.; Guenther, A.; Cao, J.; Greenberg, J.; Zhang, R.; Apel, E.; Li, G.; Weinheimer, A.; Chen, J.; Cai, C.</p> <p>2013-01-01</p> <p>The MIRAGE-Shanghai experiment was designed to characterize the factors controlling <span class="hlt">regional</span> air pollution near a Chinese Megacity (Shanghai) and was conducted during September 2009. This paper provides an overview of the measurements conducted for this study. In addition to the measurements, a <span class="hlt">regional</span> chemical/dynamical model (version 3 of Weather Research and Forecasting Chemical model - WRF-Chemv3) is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai <span class="hlt">region</span>, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability) of air pollutants in the Shanghai <span class="hlt">region</span>, and the difference between the model calculation and the measurement are mostly smaller than 30%, except the calculations of HONO at PD (Pudong) and CO at DT (Dongtan). The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a <span class="hlt">regional</span> scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger <span class="hlt">regional</span> area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large <span class="hlt">regional</span> area in the surrounding <span class="hlt">region</span> of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx-limited condition. The threshold value is strongly dependent on the emission ratio of NOx/VOCs. When the ratio is about 0.4, the Shanghai <span class="hlt">region</span> is under a strong VOC-limited condition over the <span class="hlt">regional</span> scale. In contrast, when the ratio is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21143248','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21143248"><span id="translatedtitle">Study of the tensor correlation in a neutron-rich sd-shell <span class="hlt">region</span> with mean-<span class="hlt">field</span> and beyond-mean-<span class="hlt">field</span> methods</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sugimoto, Satoru; Toki, Hiroshi; Ikeda, Kiyomi</p> <p>2008-04-29</p> <p>We study the effect of the tensor force on nuclear structure with mean-<span class="hlt">field</span> and beyond-mean-<span class="hlt">field</span> methods. An important correlation induced by the tensor force is a two-particle-two-hole (2p2h) correlation, which cannot be treated with a standard mean-<span class="hlt">field</span> method. To treat the 2p2h tensor correlation, we develop a new framework [charge- and parity-projected Hartree-Fock (CPPHF) method], which is a beyond-mean-<span class="hlt">field</span> method. In the CPPHF method, we introduce single-particle states with parity and charge mixing. The parity and charge projections are performed on a total wave function before variation. We apply the CPPHF method to oxygen isotopes including neutron-rich ones. The potential energy from the tensor force has the same order of magnitude as that from the LS force and becomes smaller with neutron number, which indicates that excess neutrons do not contribute to the 2p2h tensor correlation significantly. We also study the effect of the tensor force on spin-orbit-splitting (ls-splitting) in a neutron-rich fluorine isotope {sup 23}F. The tensor force reduces the ls-splitting for the proton d-orbits by about 3 MeV. This effect is important to reproduce the experimental value.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IzPSE..49..786K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IzPSE..49..786K"><span id="translatedtitle">Spatio-temporal variations in the structure of the attenuation <span class="hlt">field</span> of the S-wave in the <span class="hlt">region</span> of Nevada nuclear test site</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kopnichev, Yu. F.; Sokolova, I. N.; Sokolov, K. N.</p> <p>2013-11-01</p> <p>The characteristics of the attenuation <span class="hlt">field</span> of short-period shear waves in the <span class="hlt">region</span> of Nevada nuclear test site (NNTS) are studied. The seismograms of underground nuclear explosions (UNEs) and earthquakes recorded by three seismic stations in 1975-2012 at the epicentral distances of up to 1000 km are processed by the methods based on the analysis of the amplitude ratios of Sn to Pn and Lg to Pg waves, as well as the S-coda envelopes for close events. It is shown that the structure of the attenuation <span class="hlt">field</span> in the Earth's crust and upper mantle in the NNTS <span class="hlt">region</span> experienced significant temporal variations during the interval of nuclear operations. The strongest variations were associated with UNEs conducted in the Pahute Mesa area, which held about two-thirds of the most intense explosions. Our data indicate that temporal variations in the structure of the attenuation <span class="hlt">field</span> are related to the migration of deep fluids. A comparison of the general characteristics of the attenuation <span class="hlt">field</span> in the <span class="hlt">regions</span> of the three large nuclear test sites is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6327421','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6327421"><span id="translatedtitle">Superfund Record of Decision (EPA <span class="hlt">region</span> 2): Brewster Well <span class="hlt">Field</span>, Brewster, Putnam County, New York, September 1986. Final report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1986-09-30</p> <p>The Brewster Well <span class="hlt">Field</span>, located on the northern bank of the East Branch Croton River, is three-quarters of a mile east of the Village of Brewster, Town of Southeast, Putnam County, NY. Since 1954 when Well <span class="hlt">Field</span> No. 1 was developed, the Village of Brewster has used the aquifers beneath the Village-owned land as a water supply source. In 1967 Well <span class="hlt">Field</span> No. 2 was brought on line. In 1978 evidence of volatile halogenated organic compound contamination from an unidentified source first appeared. VHOs have been the primary contaminants detected in the ground water. The principal contaminants were found to be tetrachloroethylene, trichloroethylene, and 1,2-dichloroethylene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140944&keyword=SIS&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=63996537&CFTOKEN=48065767','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140944&keyword=SIS&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=63996537&CFTOKEN=48065767"><span id="translatedtitle">SITE IVESTIGATIONS (SI) AND <span class="hlt">FIELD</span> INVESTIGATIONS (FI) OF <span class="hlt">REGION</span> 4 SUPERFUND HAZARDOUS WASTE SITES: JUNE 2004 - SEPT. 2005</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>These projects require developing and implementing work plans which include a Project Operations Plan, <span class="hlt">Field</span> Sampling and Analysis Plan, Quality Assurance Plan, and a Health and Safety Plan. In general, these large complex investigations involve: collecting soil, sediment, surfac...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19990067275&hterms=tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dtide','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19990067275&hterms=tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dtide"><span id="translatedtitle">Polar/Tide Observations of <span class="hlt">Field</span> Aligned O(+) Flows at 5000 km Altitude over the Auroral <span class="hlt">Regions</span> in Comparison to UVI Auroral Images</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stevenson, Benjamin Adam; Craven, Paul D.; Chandler, Michael O.; Moore, Thomas E.; Giles, Barbara L.; Parks, G. K.; Pollock, Craig J.</p> <p>1999-01-01</p> <p>Measurements of thermal O(+) ion parameters from the Thermal Ion Dynamics Experiment (TIDE) on POLAR obtained near 5000 km altitude are compared with auroral images from the Ultra Violet Imager (UVI), for southern perigee passes. Ion parameters, including parallel velocity, density, and flux are combined with simultaneous auroral images to investigate relationships between their properties and the structure and brightness of the auroral forms. Results indicate <span class="hlt">field</span> aligned upflowing O(+) ions over bright auroral <span class="hlt">regions</span> and downward flows over dark <span class="hlt">regions</span>. These and other relationships will be presented for several POLAR passes when both ion measurements and auroral images are observed under favorable conditions for comparison.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/835938','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/835938"><span id="translatedtitle">USING CABLE SUSPENDED SUBMERSIBLE PUMPS TO REDUCE PRODUCTION COSTS TO INCREASE ULTIMATE RECOVERY IN THE RED MOUNTAIN <span class="hlt">FIELD</span> OF THE SAN JUAN BASIN <span class="hlt">REGION</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Don L. Hanosh</p> <p>2004-11-01</p> <p>This report discusses: (1) being able to resume marginal oil production operations in the Red Mountain Oil <span class="hlt">Field</span>, located in McKinley County, New Mexico by installing a cable suspended electric submersible pumping system (HDESP); (2) determining if this system can reduce life costs making it a more cost effective production system for similar oil <span class="hlt">fields</span> within the <span class="hlt">region</span>, and if warranted, drill additional wells to improve the economics. In April 2003, a cooperative 50% cost share agreement between Enerdyne and the DOE was executed to investigate the feasibility of using cable suspended electric submersible pumps to reduce the life costs and increase the ultimate oil recovery of the Red Mountain Oil <span class="hlt">Field</span>, located on the Chaco Slope of the San Juan Basin, New Mexico. The <span class="hlt">field</span> was discovered in 1934 and has produced approximately 55,650 cubic meters (m{sup 3}), (350,000 barrels, 42 gallons) of oil. Prior to April 2003, the <span class="hlt">field</span> was producing only a few cubic meters of oil each month; however, the reservoir characteristics suggest that the <span class="hlt">field</span> retains ample oil to be economic. This <span class="hlt">field</span> is unique, in that, the oil accumulations, above fresh water, occur at depths from 88-305 meters, (290 feet to 1000 feet), and serves as a relatively good test area for this experiment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008ARep...52..852C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008ARep...52..852C"><span id="translatedtitle">Magnetic-<span class="hlt">field</span> variations in the active <span class="hlt">region</span> NOAA 10486 and their relationship to X-ray flares and coronal mass ejections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chumak, O. V.; Zhang, H.-Q.; Guo, J.</p> <p>2008-10-01</p> <p>SOHO/MDI magnetograms are used to analyze the time variations in the magnetic parameters of the active <span class="hlt">region</span> (AR) NOAA 10486, which was part of a large activity complex that passed over the solar disk from October 26 to 31, 2003, during solar cycle 23. The results are compared with X-ray flares in the AR and the parameters of coronal mass ejections associated with the AR. The time variations in the distributions of themagnetic-<span class="hlt">field</span> strengths associated with the total magnetic flux (Fa), the flux imbalance between the northern and southern polarities (Im), the complexity of the <span class="hlt">field</span>, as a measure of the mutual overlapping of the opposite polarities (Co), and the tilt angle of the magnetic axis (An) are considered. The time variations in the free energy accumulated in current sheets of ARs were traced using a parameter introduced for this purpose (Sh). The following results were obtained. First, the parameters Fa, Im, Co, An, and Sh quantitatively describe the current state of the AR and can be used to trace and analyze the dynamical evolution of its magnetic <span class="hlt">field</span>. Second, variations in the magnetic-<span class="hlt">field</span>-strength distributions and the mean values of Fa, Im, Co, An, and Sh are associated with flares and coronal mass ejections, and the variations have considerable amplitudes. Third, the parameter Sh characterizing the degree to which the magnetic <span class="hlt">field</span> is non-potential in <span class="hlt">regions</span> adjacent to the main neutral line increases before eruptive events, and is thus particular interest for monitoring the states of ARs in real time. Fourth, the magnetic <span class="hlt">field</span> of the AR manifests a sort of quasi-elasticity, so that the <span class="hlt">field</span> structure is restored after active events, on average, within 1 3 h.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPD....47.1209W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPD....47.1209W"><span id="translatedtitle">Relation between Intensity Contrast and Magnetic <span class="hlt">Field</span> for Active and Quiet <span class="hlt">Regions</span> Observed on the Solar Photosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whitney, Taylor; Criscuoli, Serena; Norton, Aimee Ann</p> <p>2016-05-01</p> <p>Current solar modeling techniques assume that active and quiet <span class="hlt">regions</span> can be considered in the same manner. However, recent results from numerical simulations and high-spatial resolution observations indicate that radiative properties of small magnetic elements depend on whether they are located in plages, network, or quiet areas. These studies have been carried out typically at, or close to, disk center. In this study, data from the Helioseismic Magnetic Imager (HMI) are used to investigate the differences between magnetic elements located in Network/Quiet and Active <span class="hlt">Regions</span> (AR) observed at different positions over the solar disk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/8204','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/8204"><span id="translatedtitle"><span class="hlt">Field</span> Trip Guide to Serpentinite, Silica-Carbonate Alteration, and Related Hydrothermal Activity in the Clear Lake <span class="hlt">Region</span>, California</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fraser Goff; George Guthrie</p> <p>1999-06-01</p> <p>This guide is designed to familiarize scientists with the geology, structure, alteration, and fluids typical of California serpentinites for purposes of carbon dioxide sequestration (Lackner et al., 1995). Goff et al. (1997) and Goff and Lackner (1998) describe the geology and geochemistry of some of the serpentinites from this area. Mechanisms of silica-carbonate alteration were outlined by Barnes et al. (1973). Donnelly-Nolan et al. (1993) most recently reviewed relations between <span class="hlt">regional</span> hydrothermal alteration and Quarternary volcanic activity. Stanley et al. (1998) summarized geophysical characteristics of the <span class="hlt">region</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000037756&hterms=magnetic+coupling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmagnetic%2Bcoupling','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000037756&hterms=magnetic+coupling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmagnetic%2Bcoupling"><span id="translatedtitle">An Assessment of Magnetic Conditions for Strong Coronal Heating in Solar Active <span class="hlt">Regions</span> by Comparing Observed Loops with Computed Potential <span class="hlt">Field</span> Lines</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gary, G. A.; Moore, R. L.; Porter, J. G.; Falconer, D. A.</p> <p>1999-01-01</p> <p>We report further results on the magnetic origins of coronal heating found from registering coronal images with photospheric vector magnetograms. For two complementary active <span class="hlt">regions</span>, we use computed potential <span class="hlt">field</span> lines to examine the global non-potentiality of bright extended coronal loops and the three-dimensional structure of the magnetic <span class="hlt">field</span> at their feet, and assess the role of these magnetic conditions in the strong coronal heating in these loops. The two active <span class="hlt">regions</span> are complementary, in that one is globally potential and the other is globally nonpotential, while each is predominantly bipolar, and each has an island of included polarity in its trailing polarity domain. We find the following: (1) The brightest main-arch loops of the globally potential active <span class="hlt">region</span> are brighter than the brightest main- arch loops of the globally strongly nonpotential active <span class="hlt">region</span>. (2) In each active <span class="hlt">region</span>, only a few of the mainarch magnetic loops are strongly heated, and these are all rooted near the island. (3) The end of each main-arch bright loop apparently bifurcates above the island, so that it embraces the island and the magnetic null above the island. (4) At any one time, there are other main-arch magnetic loops that embrace the island in the same manner as do the bright loops but that are not selected for strong coronal heating. (5) There is continual microflaring in sheared core <span class="hlt">fields</span> around the island, but the main-arch bright loops show little response to these microflares. From these observational and modeling results we draw the following conclusions: (1) The heating of the main-arch bright loops arises mainly from conditions at the island end of these loops and not from their global non-potentiality. (2) There is, at most, only a loose coupling between the coronal heating in the bright loops of the main arch and the coronal heating in the sheared core <span class="hlt">fields</span> at their feet, although in both the heating is driven by conditions/events in and around the</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000ApJ...528.1004F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000ApJ...528.1004F"><span id="translatedtitle">An Assessment of Magnetic Conditions for Strong Coronal Heating in Solar Active <span class="hlt">Regions</span> by Comparing Observed Loops with Computed Potential <span class="hlt">Field</span> Lines</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Falconer, D. A.; Gary, G. A.; Moore, R. L.; Porter, J. G.</p> <p>2000-01-01</p> <p>We report further results on the magnetic origins of coronal heating found from registering coronal images with photospheric vector magnetograms. For two complementary active <span class="hlt">regions</span>, we use computed potential <span class="hlt">field</span> lines to examine the global nonpotentiality of bright extended coronal loops and the three-dimensional structure of the magnetic <span class="hlt">field</span> at their feet, and assess the role of these magnetic conditions in the strong coronal heating in these loops. The two active <span class="hlt">regions</span> are complementary, in that one is globally potential and the other is globally nonpotential, while each is predominantly bipolar, and each has an island of included polarity in its trailing polarity domain. We find the following: (1) The brightest main-arch loops of the globally potential active <span class="hlt">region</span> are brighter than the brightest main-arch loops of the globally strongly nonpotential active <span class="hlt">region</span>. (2) In each active <span class="hlt">region</span>, only a few of the mainarch magnetic loops are strongly heated, and these are all rooted near the island. (3) The end of each main-arch bright loop apparently bifurcates above the island, so that it embraces the island and the magnetic null above the island. (4) At any one time, there are other main-arch magnetic loops that embrace the island in the same manner as do the bright loops but that are not selected for strong coronal heating. (5) There is continual microflaring in sheared core <span class="hlt">fields</span> around the island, but the main-arch bright loops show little response to these microflares. From these observational and modeling results we draw the following conclusions: (1) The heating of the main-arch bright loops arises mainly from conditions at the island end of these loops and not from their global nonpotentiality. (2) There is, at most, only a loose coupling between the coronal heating in the bright loops of the main arch and the coronal heating in the sheared core <span class="hlt">fields</span> at their feet, although in both the heating is driven by conditions/events in and around the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NHESS..11.1959P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NHESS..11.1959P"><span id="translatedtitle">Ultra Low Frequency (ULF) European multi station magnetic <span class="hlt">field</span> analysis before and during the 2009 earthquake at L'Aquila regarding <span class="hlt">regional</span> geotechnical information</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prattes, G.; Schwingenschuh, K.; Eichelberger, H. U.; Magnes, W.; Boudjada, M.; Stachel, M.; Vellante, M.; Villante, U.; Wesztergom, V.; Nenovski, P.</p> <p>2011-07-01</p> <p>This work presents ground based Ultra Low Frequency (ULF) magnetic <span class="hlt">field</span> measurements in the frequency range from 10-15 mHz from 1 January 2008 to 14 April 2009. In this time period a strong earthquake series hit the Italian Abruzzo <span class="hlt">region</span> around L'Aquila with the main stroke of magnitude M = 6.3 on 6 April 2009. In the frame of the South European Geomagnetic Array (SEGMA), a European collaboration runs ULF fluxgate instruments providing continuously magnetic <span class="hlt">field</span> data recorded in mid- and south Europe. The main scientific objective is the investigation of signal variations due to seismic activity and the discrimination between other natural and human influences. The SEGMA station closest to the L'Aquila earthquake epicenter is L'Aquila observatory located in the epicenter <span class="hlt">region</span>. For the scientific analysis we extract the nighttime period from 22:00-02:00 UT and determine the power spectral density (PSD) of the horizontal (H) and vertical (Z) magnetic <span class="hlt">field</span> components and the standardized polarization ratio (Z) over (H). To discriminate local emissions from global geomagnetic effects, data from three SEGMA stations in distances up to 630 km from the epicenter <span class="hlt">region</span> are analyzed and further compared to the independent global geomagnetic ∑ Kp index. Apart from indirect ionospheric effects, electromagnetic noise could be originated in the lithosphere due to tectonic mechanisms in the earthquake focus. To estimate the amplitude of assumed lithospheric electromagnetic noise emissions causing anomalies in the PSD of the (Z) component, we consider magnetotelluric calculations of the electric crust conductivity in the L'Aquila <span class="hlt">region</span>. Results found at L'Aquila observatory are interpreted with respect to the lithosphere electrical conductivity in the local observatory <span class="hlt">region</span>, the ∑ Kp index, and further in a multi station analysis. Possible seismic related ULF anomalies occur ~2 weeks before the main stroke.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSA23B4071W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSA23B4071W"><span id="translatedtitle">The Role of Polar Cap Flux Tube Deformation and Magnetosheath Plasma Beta in the Saturation of the <span class="hlt">Region</span> 1 <span class="hlt">Field</span>-Aligned Current System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilder, F. D.; Eriksson, S.; Wiltberger, M. J.</p> <p>2014-12-01</p> <p>The phenomena of cross-polar cap potential (CPCP) and ionospheric <span class="hlt">field</span>-aligned current (FAC) saturation remains largely unexplained. In this study, we expand upon the Alfvén Wing model of CPCP saturation by investigating its impact on the magnetosphere-ionosphere current system, particularly the <span class="hlt">Region</span> 1 FAC input into the polar cap. Our hypothesis is that the ability of open flux tubes to deform in response to applied fluid stress from the magnetosheath is governed by the magnetosheath plasma beta, which in turn governs the Maxwell stress imposed on ionospheric plasma from the magnetosphere. This leads both the <span class="hlt">Region</span> 1 FAC input as well as the ionospheric convection strength, as represented by the CPCP, to saturate in response to the interplanetary magnetic <span class="hlt">field</span> (IMF) driving. We perform 32 simulations using the Lyon-Fedder-Mobarry (LFM) Magnetohydrodynamic (MHD) model with varying solar wind density and IMF strength, and demonstrate that the plasma beta does govern the deformation of polar cap and lobe <span class="hlt">field</span> lines, as well as the non-linear response of the <span class="hlt">Region</span> 1 FAC system to increasingly southward IMF. Further, we show that the current-voltage relationship in the ionosphere also shows a dependence on the plasma beta in the magnetosheath, with the ionosphere becoming more resistive at lower beta.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AnGeo..27.4229S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AnGeo..27.4229S"><span id="translatedtitle">Observational evidence for the plausible linkage of Equatorial Electrojet (EEJ) electric <span class="hlt">field</span> variations with the post sunset F-<span class="hlt">region</span> electrodynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sreeja, V.; Devasia, C. V.; Ravindran, Sudha; Pant, Tarun Kumar</p> <p>2009-11-01</p> <p>The paper is based on a detailed observational study of the Equatorial Spread F (ESF) events on geomagnetically quiet (Ap≤20) days of the solar maximum (2001), moderate (2004) and minimum (2006) years using the ionograms and magnetograms from the magnetic equatorial location of Trivandrum (8.5° N; 77° E; dip lat ~0.5° N) in India. The study brings out some interesting aspects of the daytime Equatorial Electrojet (EEJ) related electric <span class="hlt">field</span> variations and the post sunset F-<span class="hlt">region</span> electrodynamics governing the nature of seasonal characteristics of the ESF phenomena during these years. The observed results seem to indicate a plausible linkage of daytime EEJ related electric <span class="hlt">field</span> variations with pre-reversal enhancement which in turn is related to the occurrence of ESF. These electric <span class="hlt">field</span> variations are shown to be better represented through a parameter, termed as "E", in the context of possible coupling between the E- and F-<span class="hlt">regions</span> of the ionosphere. The observed similarities in the gross features of the variations in the parameter "E" and the F-<span class="hlt">region</span> vertical drift (Vz) point towards the potential usage of the EEJ related parameter "E" as an useful index for the assessment of Vz prior to the occurrence of ESF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5311228','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5311228"><span id="translatedtitle">Obliquely propagating ion acoustic waves in the auroral E <span class="hlt">region</span>: Further evidence of irregularity production by <span class="hlt">field</span>-aligned electron streaming</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Villain, J.P. ); Hanuise, C. ); Greenwald, R.A.; Baker, K.B.; Ruohoniemi, J.M. )</p> <p>1990-06-01</p> <p>Common volume observations of E <span class="hlt">region</span> high-latitude irregularities at decameter wavelengths have been obtained with the JHU/APL HF radar located at Goose Bay, Labrador, and the SHERPA HF radar located at Schefferville, Quebec. In this paper, the authors analyze an event with characteristics similar to those of a distinctive type of event described by Villain et al. (1987). The experimental configuration, which combines the azimuthal-scanning capability of the Goose Bay radar with the frequency-scanning operation of the Schefferville radar, has provided unambiguous evidence of the existence of two irregularity layers at different altitudes within the E <span class="hlt">region</span>. The layers, which exhibit different characteristics, can be related to the action of the gradient drift and ion acoustic instability mechanisms. It is shown that the ion acoustic modes have phase velocities in the range of 400 to 550 m/s and are produced in <span class="hlt">regions</span> of subcritical perpendicular electron Hall drift. They infer that the observed irregularities are produced through a combination of perpendicular and <span class="hlt">field</span>-aligned relative electron-ion drifts. Features previously observed but no t satisfactorily explained by perpendicular drift excitation alone can be understood in terms of <span class="hlt">field</span>-aligned drift excitation. They conclude that the role of electron-ion <span class="hlt">field</span>-aligned drift may be much more important than previously realized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19890064417&hterms=variance&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dvariance','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19890064417&hterms=variance&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dvariance"><span id="translatedtitle">The proton temperature and the total hourly variance of the magnetic <span class="hlt">field</span> components in different solar wind speed <span class="hlt">regions</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tu, Chuan-Yi; Freeman, John W.; Lopez, R. E.</p> <p>1989-01-01</p> <p>A comparison has been made between the predictions of the theory for radial variations of both Alfvenic fluctuations and solar wind proton temperatures proposed by Tu (1987, 1988) and the statistical results of hourly averaged plasma and magnetic <span class="hlt">field</span> data observed by Helios 1 and 2 from launch through 1980 for different solar wind speed regimes. The comparison shows that for speed ranges between 500-800 km/s, the radial variation of the proton temperature between 0.3 and 1 AU can be explained by heating from the cascade energy which is determined by the radial variation of the total variance of magnetic <span class="hlt">field</span> vector.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001ApJ...548..127T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001ApJ...548..127T"><span id="translatedtitle">Wide-<span class="hlt">Field</span> Imaging of the Hubble Deep <span class="hlt">Field</span>-South <span class="hlt">Region</span>. II. The Evolution of Galaxy Clustering at z < 1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Teplitz, Harry I.; Hill, Robert S.; Malumuth, Eliot M.; Collins, Nicholas R.; Gardner, Jonathan P.; Palunas, Povilas; Woodgate, Bruce E.</p> <p>2001-02-01</p> <p>We present the galaxy-galaxy angular correlations as a function of photometric redshift in a deep, wide galaxy survey centered on the Hubble Deep <span class="hlt">Field</span>-South (HDF-S). Images were obtained with the Big Throughput Camera on the Blanco 4 m telescope at CTIO, of 1/2 square degree in broadband uBVRI, reaching ~24 mag. Approximately 40,000 galaxies are detected in the survey. We determine photometric redshifts using galaxy template fitting to the photometry. Monte Carlo simulations show that redshifts from these data should be reliable out to z~1, where the 4000 Å break shifts into the I band. The inferred redshift distribution, n(z), shows good agreement with the distribution of galaxies measured in the Hubble Deep <span class="hlt">Field</span>-North (HDF-N) and the Canada-France Redshift Survey. After assigning galaxies to redshift bins with width Δz=0.33, we determine the two-point angular correlation function in each bin. We find that the amplitude of the correlation, Aw, drops across the three bins to redshift z~1. Simple ɛ models of clustering evolution fit this result, with the best agreement for ɛ=0. Hierarchical cold dark matter models best fit in a low-density, Λ-dominated universe. Based on observations obtained at Cerro Tololo Inter-American Observatory, a division of the National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ExFl...53..353S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ExFl...53..353S"><span id="translatedtitle">Identification of vortical structures inside the human pharynx/larynx <span class="hlt">region</span> from POD-reconstructed velocity <span class="hlt">fields</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shinneeb, A.-M.; Pollard, Andrew</p> <p>2012-08-01</p> <p>This paper reports an experimental investigation of the vortical structures in the pharynx/larynx <span class="hlt">region</span> of an idealised human extra-thoracic airway obtained using particle image velocimetry (PIV). The inlet velocity was 0.13 m/s yielding a Reynolds number, based on the inlet condition, of 670. Two thousand images were acquired at each location at a framing rate of 2 Hz. The proper orthogonal decomposition method was applied to the PIV data. Only a few modes were used for POD reconstruction which recovered about 60 % of the turbulent kinetic energy. A vortex identification algorithm was employed to identify and measure properties of the structures. This step was followed by a statistical analysis of the distribution of number, size, and strength of these vortices. The results reveal the formation of a large number of structures identified along two planes in the pharynx/larynx <span class="hlt">region</span>. This study also revealed an increased strength in the counter-clockwise structures as compared to clockwise structures in the pharynx <span class="hlt">region</span>. As well, there is some evidence to suggest that the vortical structures, whose axes are perpendicular to the sagittal plane, change their orientation as they proceed further into the laryngeal <span class="hlt">region</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=222271','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=222271"><span id="translatedtitle">Utility of Thermal Image Sharpening for Monitoring <span class="hlt">Field</span>-Scale Evapotranspiration over Rainfed and Irrigated Agricultural <span class="hlt">Regions</span></span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>The utility of a thermal image sharpening algorithm (TsHARP) in providing fine resolution land surface temperature (LST) data to a Two-Source-Model (TSM) for mapping evapotranspiration (ET) was examined over two agricultural <span class="hlt">regions</span> in the U.S. One site is in a rainfed corn and soybean production r...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=306430','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=306430"><span id="translatedtitle">Application of thermal-based two-source energy balance model for estimating vineyard evapotranspiration at <span class="hlt">field</span> and <span class="hlt">regional</span> scales</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Due to limited water availability in much of California, particularly in the Central Valley <span class="hlt">region</span> where one-third of the produce consumed in the United States is grown, improvements in water and irrigation management practices are greatly needed. This, in turn, requires the development of tools and...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=206491','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=206491"><span id="translatedtitle">LONG-TERM AGRONOMIC PERFORMANCE OF ORGANIC AND CONVENTIONAL <span class="hlt">FIELD</span> CROPS IN THE MID-ATLANTIC <span class="hlt">REGION</span></span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Despite increasing interest in organic grain crop production among farmers, government agencies and others, there is little information on expected crop yields and production challenges in organic grain production, especially in Coastal Plain soils of the mid-Atlantic <span class="hlt">region</span>. The USDA-ARS Beltsville...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=221045','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=221045"><span id="translatedtitle">Long-term economic performance of organic and conventional <span class="hlt">field</span> crops in the mid-Atlantic <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Interest in organic grain production is increasing in the United States but there is limited information regarding the economic performance of organic grain and forage production in the mid-Atlantic <span class="hlt">region</span>. We present the results from enterprise budget analyses for individual crops and for complete...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=ecuador+AND+learning&pg=4&id=ED285791','ERIC'); return false;" href="http://eric.ed.gov/?q=ecuador+AND+learning&pg=4&id=ED285791"><span id="translatedtitle">The Major Project in the <span class="hlt">Field</span> of Education in the Latin American and Caribbean <span class="hlt">Region</span>. Bulletin 9.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and Caribbean.</p> <p></p> <p>The speed at which transformations have occurred in levels of knowledge--especially scientific and technical knowledge--obliges countries in the Latin American and Caribbean <span class="hlt">region</span> to undergo a rapid process of modernization. An educational project of UNESCO was established with this goal in mind. This bulletin presents three articles concerning…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=213238','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=213238"><span id="translatedtitle">LONG-TERM AGRONOMIC PERFORMANCE OF ORGANIC AND CONVENTIONAL <span class="hlt">FIELD</span> CROPS IN THE MID-ATLANTIC <span class="hlt">REGION</span></span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Despite increasing interest in organic grain crop production among farmers, government agencies and other stakeholders, there is little information on expected crop yields and production challenges in organic grain production, especially in Coastal Plain soils of the mid-Atlantic <span class="hlt">region</span>. The USDA-AR...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=221196','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=221196"><span id="translatedtitle"><span class="hlt">Field</span> evaluation of anthracnose disease response for the sorghum germplasm collection from the Kayes <span class="hlt">region</span> of Mali</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Sorghum germplasm from the Kayes <span class="hlt">region</span> of Mali maintained in the USDA, ARS National Plant Germplasm System was inoculated with Colletotrichum sublineolum and evaluated for foliar anthracnose resistance in 2003 and 2004 at the USDA, ARS Tropical Agriculture Research Station in Isabela, Puerto Rico. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMSH41B2105J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMSH41B2105J"><span id="translatedtitle">Study of the 3D Coronal Magnetic <span class="hlt">Field</span> of Active <span class="hlt">Region</span> 11117 Around the Time of a Confined Flare Using a Data-Driven CESE-MHD Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, C.; Feng, X.; Wu, S.; Hu, Q.</p> <p>2012-12-01</p> <p>Non-potentiality of the solar coronal magnetic <span class="hlt">field</span> accounts for the solar explosion like flares and CMEs. We apply a data-driven CESE-MHD model to investigate the three-dimensional (3D) coronal magnetic <span class="hlt">field</span> of NOAA active <span class="hlt">region</span> (AR) 11117 around the time of a C-class confined flare occurred on 2010 October 25. The CESE-MHD model, based on the spacetime conservation-element and solution-element scheme, is designed to focus on the magnetic-<span class="hlt">field</span> evolution and to consider a simplified solar atomsphere with finite plasma β. Magnetic vector-<span class="hlt">field</span> data derived from the observations at the photoshpere is inputted directly to constrain the model. Assuming that the dynamic evolution of the coronal magnetic <span class="hlt">field</span> can be approximated by successive equilibria, we solve a time sequence of MHD equilibria basing on a set of vector magnetograms for AR 11117 taken by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamic Observatory (SDO) around the time of flare. The model qualitatively reproduces the basic structures of the 3D magnetic <span class="hlt">field</span>, as supported by the visual similarity between the <span class="hlt">field</span> lines and the coronal loops observed by the Atmospheric Imaging Assembly (AIA), which shows that the coronal <span class="hlt">field</span> can indeed be well characterized by the MHD equilibrium in most time. The magnetic configuration changes very limited during the studied time interval of two hours. A topological analysis reveals that the small flare is correlated with a bald patch (BP, where the magnetic <span class="hlt">field</span> is tangent to the photoshpere), suggesting that the energy release of the flare can be understood by magnetic reconnection associated with the BP separatrices. The total magnetic flux and energy keep increasing slightly in spite of the flare, while the magnetic free energy drops during the flare with an amount of 1.7 × 1030 erg, which can be interpreted as the energy budget released by the minor C-class flare.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.2036W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.2036W"><span id="translatedtitle">The role of magnetic flux tube deformation and magnetosheath plasma beta in the saturation of the <span class="hlt">Region</span> 1 <span class="hlt">field</span>-aligned current system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilder, F. D.; Eriksson, S.; Wiltberger, M.</p> <p>2015-03-01</p> <p>The phenomena of cross polar cap potential (CPCP) and ionospheric <span class="hlt">field</span>-aligned current (FAC) saturation remain largely unexplained. In the present study, we expand upon the Alfvén wing model of CPCP saturation by investigating its impact on the magnetosphere-ionosphere current system, particularly the <span class="hlt">Region</span> 1 FAC input into the polar cap. Our hypothesis is that the ability of open flux tubes to deform in response to applied fluid stress from the magnetosheath is governed by the magnetosheath plasma beta, which in turn governs the Maxwell stress imposed on ionospheric plasma from the magnetosphere. We performed 32 MHD simulations with varying solar wind density and interplanetary magnetic <span class="hlt">field</span> strength and show that the plasma beta does govern the deformation of open <span class="hlt">field</span> lines, as well as the nonlinear response of the <span class="hlt">Region</span> 1 FAC system to increasingly southward interplanetary magnetic <span class="hlt">field</span>. Further, we show that the current-voltage relationship in the ionosphere also shows a dependence on the plasma beta in the magnetosheath, with the ionosphere becoming more resistive at lower beta.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=management+AND+accounting&pg=6&id=EJ726456','ERIC'); return false;" href="http://eric.ed.gov/?q=management+AND+accounting&pg=6&id=EJ726456"><span id="translatedtitle">Determinants of Success on the ETS Business Major <span class="hlt">Field</span> Exam for Students in an Undergraduate Multisite <span class="hlt">Regional</span> University Business Program</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bagamery, Bruce D.; Lasik, John J.; Nixon, Don R.</p> <p>2005-01-01</p> <p>Extending previous studies, the authors examined a larger set of variables to identify predictors of student performance on the Educational Testing Service Major <span class="hlt">Field</span> Exam in Business, which has been shown to be an externally valid measure of student learning outcomes. Significant predictors include gender, whether students took the SAT, and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=technical+AND+program+AND+plan+AND+international+AND+technical+AND+evaluation&pg=3&id=ED242455','ERIC'); return false;" href="http://eric.ed.gov/?q=technical+AND+program+AND+plan+AND+international+AND+technical+AND+evaluation&pg=3&id=ED242455"><span id="translatedtitle">The Major Project in the <span class="hlt">Field</span> of Education in the Latin American and Caribbean <span class="hlt">Region</span>. Bulletin 4.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and Caribbean.</p> <p></p> <p>The initiative and activities carried out by 29 countries in Latin and South America and the Caribbean in the UNESCO Major Project in the <span class="hlt">Field</span> of Education to correct deficiencies and meet unsatisfied basic educational needs are summarized. Many summaries reflect revisions made during 1983 in National Plans of Action with respect to enhancing…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19920036694&hterms=Zeeman+effect&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2528Zeeman%2Beffect%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19920036694&hterms=Zeeman+effect&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2528Zeeman%2Beffect%2529"><span id="translatedtitle">The Zeeman effect in astrophysical water masers and the observation of strong magnetic <span class="hlt">fields</span> in <span class="hlt">regions</span> of star formation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nedoluha, Gerald E.; Watson, William D.</p> <p>1992-01-01</p> <p>The present study solves the transfer equations for the polarized radiation of astrophysical 22-GHz water masers in the presence of a magnetic <span class="hlt">field</span> which causes a Zeeman splitting that is much smaller than the spectral line breadth. The emphasis is placed on the relationship between the recently detected circular polarization in this maser radiation and the strength of the magnetic <span class="hlt">field</span>. When the observed spectral line breadth is smaller than about 0.8 km/s (FWHM), it is calculated that the uncertainty is less than a factor of about 2. The accuracy is improved significantly when the angle between the line of sight and the direction of the magnetic <span class="hlt">field</span> does not exceed about 45 deg. Uncertainty in the strength of the magnetic <span class="hlt">field</span> due to lack of knowledge about which hyperfine transition is the source of the 22-GHz masers is removed. The 22-GHz maser feature is found to be the result of a merger of the three strongest hyperfine components.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Santiago+AND+Cuba&id=ED288765','ERIC'); return false;" href="http://eric.ed.gov/?q=Santiago+AND+Cuba&id=ED288765"><span id="translatedtitle">The Major Project in the <span class="hlt">Field</span> of Education in the Latin American and Caribbean <span class="hlt">Region</span>. Bulletin 10-11.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.</p> <p></p> <p>The Major Project in the <span class="hlt">Field</span> of Education stresses renewed and intensive efforts by Latin American and Caribbean Island countries to provide the resources and training necessary to meet basic education needs by the year 2000. This document examines project achievements, innovations, and problems through 1986 in the areas of rural education,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Hale&pg=7&id=EJ004437','ERIC'); return false;" href="http://eric.ed.gov/?q=Hale&pg=7&id=EJ004437"><span id="translatedtitle">Northwest <span class="hlt">Regional</span> Educational Laboratory--A Competency Based, Personalized and <span class="hlt">Field</span>-Centered Model of an Elementary Teacher Education Program</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Schalock, H. Del</p> <p>1969-01-01</p> <p>Adapted from Schalock, H.D. and Hale, Jr. R. (eds), "A Competency Based, <span class="hlt">Field</span> Centered Systems Approach to Elementary Teacher Education, v I, II and III (Final Report for Project 89022, Bureau of Research, U.S. Office of Education).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6951134','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6951134"><span id="translatedtitle">Superfund Record of Decision (EPA <span class="hlt">Region</span> 4): Naval Air Station Cecil <span class="hlt">Field</span>, Operable Unit 6, Jacksonville, FL, September 1994</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1994-09-01</p> <p>The site name is the Golf Course Pesticide Disposal Area, Site 11, Operable Unit (OU) 6. The site is located in a wooded area between the 11th fairway and the 17th green at the Naval Air Station (NAS) Cecil <span class="hlt">Field</span> golf course, Jacksonville, Florida. The purpose of the interim remedial action is to remove buried containers of pesticides and associated contaminated soil.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840018026','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840018026"><span id="translatedtitle"><span class="hlt">Field</span> data observed during the geological excursion in the west-central <span class="hlt">region</span> of the Sul-Riogrande Shield</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parada, N. D. J. (Principal Investigator); Ohara, T.</p> <p>1984-01-01</p> <p>Outcrops are studied in the Copper Project test area of the Rio Grande do Sul State of Brazil. The accuracy of LANDSAT-MSS data is checked against <span class="hlt">field</span> data. A preliminary geological map is included on a scale of 1:500,000 that describes 820 outcrop over an area of 1,700 kilometers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=202050','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=202050"><span id="translatedtitle">Using the RZWQM to Simulate the Fate of Nitrogen in <span class="hlt">Field</span> Soil - Crop Environment in the Mediterranean <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Water and Nitrogen (N) balances in agricultural systems are important for evaluating management effects on environmental quality. This paper presents an evaluation of the Root Zone Water Quality Model (RZWQM) for assessing the fate of N in the soil-crop environment at the <span class="hlt">field</span> scale in Portugal und...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8427E..4DK','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8427E..4DK"><span id="translatedtitle">Anti-Stokes effect CCD camera and SLD based optical coherence tomography for full-<span class="hlt">field</span> imaging in the 1550nm <span class="hlt">region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kredzinski, Lukasz; Connelly, Michael J.</p> <p>2012-06-01</p> <p>Full-<span class="hlt">field</span> Optical coherence tomography is an en-face interferometric imaging technology capable of carrying out high resolution cross-sectional imaging of the internal microstructure of an examined specimen in a non-invasive manner. The presented system is based on competitively priced optical components available at the main optical communications band located in the 1550 nm <span class="hlt">region</span>. It consists of a superluminescent diode and an anti-stokes imaging device. The single mode fibre coupled SLD was connected to a multi-mode fibre inserted into a mode scrambler to obtain spatially incoherent illumination, suitable for OCT wide-<span class="hlt">field</span> modality in terms of crosstalk suppression and image enhancement. This relatively inexpensive system with moderate resolution of approximately 24um x 12um (axial x lateral) was constructed to perform a 3D cross sectional imaging of a human tooth. To our knowledge this is the first 1550 nm full-<span class="hlt">field</span> OCT system reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22365203','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22365203"><span id="translatedtitle">Quasi-static three-dimensional magnetic <span class="hlt">field</span> evolution in solar active <span class="hlt">region</span> NOAA 11166 associated with an X1.5 flare</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vemareddy, P.; Wiegelmann, T. E-mail: wiegelmann@mps.mpg.de</p> <p>2014-09-01</p> <p>We study the quasi-static evolution of coronal magnetic <span class="hlt">fields</span> constructed from the non-linear force-free <span class="hlt">field</span> (NLFFF) approximation aiming to understand the relation between the magnetic <span class="hlt">field</span> topology and ribbon emission during an X1.5 flare in active <span class="hlt">region</span> (AR) NOAA 11166. The flare with a quasi-elliptical and two remote ribbons occurred on 2011 March 9 at 23:13 UT over a positive flux <span class="hlt">region</span> surrounded by negative flux at the center of the bipolar AR. Our analysis of the coronal magnetic structure with potential and NLFFF solutions unveiled the existence of a single magnetic null point associated with a fan-spine topology and is co-spatial with the hard X-ray source. The footpoints of the fan separatrix surface agree with the inner edge of the quasi-elliptical ribbon and the outer spine is linked to one of the remote ribbons. During the evolution, the slow footpoint motions stressed the <span class="hlt">field</span> lines along the polarity inversion line and caused electric current layers in the corona around the fan separatrix surface. These current layers trigger magnetic reconnection as a consequence of dissipating currents, which are visible as cusp-shaped structures at lower heights. The reconnection process reorganized the magnetic <span class="hlt">field</span> topology whose signatures are observed at the separatrices/quasi-separatrix layer structure in both the photosphere and the corona during the pre-to-post flare evolution. In agreement with previous numerical studies, our results suggest that the line-tied footpoint motions perturb the fan-spine system and cause null point reconnection, which eventually causes the flare emission at the footpoints of the <span class="hlt">field</span> lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21455189','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21455189"><span id="translatedtitle">HIGH-ANGULAR RESOLUTION DUST POLARIZATION MEASUREMENTS: SHAPED B-<span class="hlt">FIELD</span> LINES IN THE MASSIVE STAR-FORMING <span class="hlt">REGION</span> ORION BN/KL</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tang, Ya-Wen; Ho, Paul T. P.; Koch, Patrick M.; Rao, Ramprasad</p> <p>2010-07-10</p> <p>We present observational results of the thermal dust continuum emission and its linear polarization in one of the nearest massive star-forming sites Orion BN/KL in Orion Molecular Cloud-1. The observations were carried out with the Submillimeter Array. With an angular resolution of 1'' ({approx}2 mpc; 480 AU), we have detected and resolved the densest cores near the BN/KL <span class="hlt">region</span>. At a wavelength of {approx}870 {mu}m, the polarized dust emission can be used to trace the structure of the magnetic <span class="hlt">field</span> in this star-forming core. The dust continuum appears to arise from a V-shaped <span class="hlt">region</span>, with a cavity nearly coincident with the center of the explosive outflows observed on larger scales. The position angles (P.A.s) of the observed polarization vary significantly by a total of about 90{sup 0} but smoothly, i.e., curl-like, across the dust ridges. Such a polarization pattern can be explained with dust grains being magnetically aligned instead of mechanically with outflows, since the latter mechanism would cause the P.A.s to be parallel to the direction of the outflow, i.e., radial-like. The magnetic <span class="hlt">field</span> projected in the plane of sky is therefore derived by rotating the P.A.s of the polarization by 90{sup 0}. We find an azimuthally symmetric structure in the overall magnetic <span class="hlt">field</span> morphology, with the <span class="hlt">field</span> directions pointing toward 2.''5 west to the center of the explosive outflows. We also find a preferred symmetry plane at a P.A. of 36{sup 0}, which is perpendicular to the mean magnetic <span class="hlt">field</span> direction (120{sup 0}) of the 0.5 pc dust ridge. Two possible interpretations of the origin of the observed magnetic <span class="hlt">field</span> structure are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9524E..1LS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9524E..1LS"><span id="translatedtitle">Dual-illumination mode, wide-<span class="hlt">field</span> probe imaging scheme for imaging irido-corneal angle <span class="hlt">region</span> inside eye</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shinoj, V. K.; Murukeshan, V. M.; Hong, Jesmond; Baskaran, M.; Aung, Tin</p> <p>2015-07-01</p> <p>Noninvasive medical imaging techniques have generated great interest and high potential in the research and development of ocular imaging and follow up procedures. It is well known that angle closure glaucoma is one of the major ocular diseases/ conditions that causes blindness. The identification and treatment of this disease are related primarily to angle assessment techniques. In this paper, we illustrate a probe-based imaging approach to obtain the images of the angle <span class="hlt">region</span> in eye. The proposed probe consists of a micro CCD camera and LED/NIR laser light sources and they are configured at the distal end to enable imaging of iridocorneal <span class="hlt">region</span> inside eye. With this proposed dualmodal probe, imaging is performed in light (white visible LED ON) and dark (NIR laser light source alone) conditions and the angle <span class="hlt">region</span> is noticeable in both cases. The imaging using NIR sources have major significance in anterior chamber imaging since it evades pupil constriction due to the bright light and thereby the artificial altering of anterior chamber angle. The proposed methodology and developed scheme are expected to find potential application in glaucoma disease detection and diagnosis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21301273','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21301273"><span id="translatedtitle">A WIDE-<span class="hlt">FIELD</span> NARROWBAND OPTICAL SURVEY OF THE BRAID NEBULA STAR FORMATION <span class="hlt">REGION</span> IN CYGNUS OB7</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Magakian, Tigran Yu.; Nikogossian, Elena H.; Movsessian, Tigran; Aspin, Colin; Pyo, Tae-Soo; Khanzadyan, Tigran; Smith, Michael D.; Mitchison, Sharon; Davis, Chris J.; Beck, Tracy L.; Moriarty-Schieven, Gerald H. E-mail: elena@bao.sci.am E-mail: pyo@subaru.naoj.org E-mail: smm23@kent.ac.uk E-mail: c.davis@jach.hawaii.edu E-mail: gerald.schieven@nrc-cnrc.gc.ca</p> <p>2010-03-15</p> <p>We study the population of Herbig-Haro (HH) flows and jets in an area of Cygnus OB7 designated the Braid Nebula star formation <span class="hlt">region</span>. This complex forms part of the L 1003 dark cloud, and hosts two FU Orionis (FUor)-like objects as well as several other active young stars. To trace outflow activity and to relate both known and newly discovered flows to young star hosts we intercompare new, deep, narrowband H{alpha} and [S II] optical images taken on the Subaru 8 m Telescope on Mauna Kea, Hawaii. Our images show that there is considerable outflow and jet activity in this <span class="hlt">region</span> suggesting the presence of an extensive young star population. We confirm that both of the FUor-like objects drive extensive HH flows and document further members of the flows in both objects. The L 1003 star formation complex is a highly kinematically active <span class="hlt">region</span> with young stars in several different stages of evolution. We trace collimated outflows from numerous young stars although the origin of some HH objects remains elusive.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Tectp.632..261O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Tectp.632..261O"><span id="translatedtitle">Stress <span class="hlt">field</span> variations along the Maghreb <span class="hlt">region</span> derived from inversion of major seismic crisis fault plane solutions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ousadou, Farida; Dorbath, Louis; Ayadi, Abdelhakim; Dorbath, Catherine; Gharbi, Sofiane</p> <p>2014-09-01</p> <p>This study is devoted to the analysis of the stress state along the Maghreb <span class="hlt">region</span> based on the inversion of focal solutions. We have inverted the main shock and aftershock focal mechanisms of the strongest seismic events that occurred in five seismogenic zones, from west to east: Al Hoceima (2004), Cheliff (1980), Tipasa-Chenoua (1989), Zemmouri (2003) and Constantine (1985). Most of the focal mechanisms of the aftershock sequences have been constructed within this study. Compressive stress regime is observed in the central part of Algeria between Cheliff and Zemmouri. On both edges of the Maghreb <span class="hlt">region</span>, the stress regime becomes strike-slip in the Constantine <span class="hlt">region</span> and in the Moroccan Rift. These different regimes seem to be linked to the free-edge effect (Ionian slab subduction) and to the dynamics of the Alboran Sea in the eastern and western parts of the study area respectively. The σ1 directions experience an anticlockwise rotation of about 20° from eastern to central Algeria. We observe that the direction of σ1 and the direction of convergence are the closest in central Algeria, where the collision is not perturbed by edge effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22020399','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22020399"><span id="translatedtitle">MAGNETIC <span class="hlt">FIELDS</span> OF AN ACTIVE <span class="hlt">REGION</span> FILAMENT FROM FULL STOKES ANALYSIS OF Si I 1082.7 nm AND He I 1083.0 nm</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xu, Z.; Liu, Y.</p> <p>2012-04-20</p> <p>Vector magnetic <span class="hlt">fields</span> of an active <span class="hlt">region</span> filament in the photosphere and upper chromosphere are obtained from spectro-polarimetric observations recorded with the Tenerife Infrared Polarimeter (TIP II) at the German Vacuum Tower Telescope. We apply Milne-Eddington inversions on full Stokes vectors of the photospheric Si I 1082.7 nm and the upper chromospheric He I triplet at 1083.0 nm to obtain the magnetic <span class="hlt">field</span> vector and velocity maps in two atmosphere layers. We find that (1) a complete filament was already present in H{alpha} at the beginning of the TIP II data acquisition. Only a partially formed one, composed of multiple small threads, was present in He I. (2) The AR filament comprises two sections. One shows strong magnetic <span class="hlt">field</span> intensities, about 600-800 G in the upper chromosphere and 800-1000 G in the photosphere. The other exhibits only comparatively weak magnetic <span class="hlt">field</span> strengths in both layers. (3) The Stokes V signal is indicative of a dip in the magnetic <span class="hlt">field</span> strength close to the chromospheric PIL. (4) In the chromosphere, consistent upflows are found along the PIL flanked by downflows. (5) The transversal magnetic <span class="hlt">field</span> is nearly parallel to the PIL in the photosphere and inclined by 20 Degree-Sign -30 Degree-Sign in the chromosphere. (6) The chromospheric magnetic <span class="hlt">field</span> around the filament is found to be in normal configuration, while the photospheric <span class="hlt">field</span> presents a concave magnetic topology. The observations are consistent with the emergence of a flux rope with a subsequent formation of a filament.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27347754','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27347754"><span id="translatedtitle">Wide <span class="hlt">field</span>-of-view, multi-<span class="hlt">region</span>, two-photon imaging of neuronal activity in the mammalian brain.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stirman, Jeffrey N; Smith, Ikuko T; Kudenov, Michael W; Smith, Spencer L</p> <p>2016-08-01</p> <p>Two-photon calcium imaging provides an optical readout of neuronal activity in populations of neurons with subcellular resolution. However, conventional two-photon imaging systems are limited in their <span class="hlt">field</span> of view to ∼1 mm(2), precluding the visualization of multiple cortical areas simultaneously. Here, we demonstrate a two-photon microscope with an expanded <span class="hlt">field</span> of view (>9.5 mm(2)) for rapidly reconfigurable simultaneous scanning of widely separated populations of neurons. We custom designed and assembled an optimized scan engine, objective, and two independently positionable, temporally multiplexed excitation pathways. We used this new microscope to measure activity correlations between two cortical visual areas in mice during visual processing. PMID:27347754</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.4507N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.4507N"><span id="translatedtitle">Assessment of the impact of moving fluids on the <span class="hlt">regional</span> thermal <span class="hlt">field</span> for the area of Brandenburg (North German Basin)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Noack, V.; Scheck-Wenderoth, M.; Cacace, M.; Lewerenz, B.</p> <p>2012-04-01</p> <p>We present results from numerical simulations of the 3D thermal <span class="hlt">field</span> for the area of Brandenburg in the North German Basin. The study area encompasses a part of the basin centre in the north, whereas to the south the basin margin is enclosed. Starting with Permocarboniferous volcanic rocks the basin fill is represented by Permian to Cenozoic sediments. A thick layer of mobilized salt (Zechstein, Upper Permian) generated elevated structures such as salt pillows and diapirs. Especially where diapirs pierce their overburden, the overlying deposits are strongly influenced in their thickness and distribution. This special configuration of the Zechstein salt is relevant for the thermal calculations due to the fact that salt has a distinctly higher thermal conductivity than the surrounding sediments and is impermeable to fluid flow. Therefore, the Zechstein salt acts as a conductive chimney for heat and a hydraulic decoupling horizon between the Pre-Permian and the Mesozoic-Cenozoic strata. The latter are characterized by two further quasi-impervious sediment complexes, the Rupelian-clay and the Muschelkalk. These two divide the Post-Permian strata in three main aquifer systems: the Buntsandstein, Keuper to Pre-Rupelian and the Post-Rupelian complex. Based on results from purely conductive modelling we additionally analyse the influence of moving fluids on the shallow temperature <span class="hlt">field</span> above the Zechstein salt. Therefore coupled fluid flow and heat transfer numerical simulations are carried out to investigate the hydrothermal <span class="hlt">field</span>. The 3D simulations for the heat transport processes are based on the finite element method. The results indicate that the distribution of thermal conductivities in the basin fill controls the short-wavelength pattern of the temperature distribution whereas the long wavelength pattern results from interaction between the highly conductive crust and low conductive sediments. Furthermore, the results reveal that the shallow temperature <span class="hlt">field</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JGeo...41..471A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JGeo...41..471A"><span id="translatedtitle">Recent crustal deformation of İzmir, Western Anatolia and surrounding <span class="hlt">regions</span> as deduced from repeated GPS measurements and strain <span class="hlt">field</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aktuğ, Bahadır; Kılıçoğlu, Ali</p> <p>2006-07-01</p> <p>To investigate contemporary neotectonic deformation in İzmir, Western Anatolia and in its neighborhood, a relatively dense Global Positioning System (GPS) monitoring network was established in 2001. Combination of three spatially dense GPS campaigns in 2001, 2003 and 2004 with temporally dense campaigns between 1992 and 2004 resulted in a combined velocity <span class="hlt">field</span> representing active deformation rate in the <span class="hlt">region</span>. We computed horizontal and vertical velocity <span class="hlt">fields</span> with respect to Earth-centered, Earth-fixed ITRF2000, to Eurasia and to Anatolia as well. The rates of principal and shear strains along with rigid-body rotation rates were derived from velocity <span class="hlt">field</span>. Results show east-west shortening between Karaburun Peninsula and northern part of İzmir Bay together with the extension of İzmir Bay in accordance with general extension regime of Western Anatolia and Eastern Agea. East-west shortening and north-south extension of Karaburun Peninsula are closely related to right-lateral faulting and a clockwise rotation. There exists a block in the middle of the peninsula with a differential motion at a rate of 3-5 ± 1 mm/year and 5-6 ± 1 mm/year to the east and south, respectively. As is in Western Anatolia, north-south extension is dominant in almost all parts of the <span class="hlt">region</span> despite the fact that they exhibit significantly higher rates in the middle of the peninsula. Extensional rates along Tuzla Fault lying nearly perpendicular to İzmir Bay and in its west are maximum in the <span class="hlt">region</span> with an extension rate of 300-500 ± 80-100 nanostrain/year and confirm its active state. Extensional rates in other parts of the <span class="hlt">region</span> are at level of 50-150 nanostrain/year as expected in the other parts of Western Anatolia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMNH51C1903P&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMNH51C1903P&link_type=ABSTRACT"><span id="translatedtitle">High resolution <span class="hlt">field</span> monitoring in coastal wetlands of the U.S. Mid-Atlantic to support quantification of storm surge attenuation at the <span class="hlt">regional</span> scale</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paquier, A. E.; Haddad, J.; Lawler, S.; Garzon Hervas, J. L.; Ferreira, C.</p> <p>2015-12-01</p> <p>Hurricane Sandy (2012) demonstrated the vulnerability of the US East Coast to extreme events, and motivated the exploration of resilient coastal defenses that incorporate both hard engineering and natural strategies such as the restoration, creation and enhancement of coastal wetlands and marshes. Past laboratory and numerical studies have indicated the potential of wetlands to attenuate storm surge, and have demonstrated the complexity of the surge hydrodynamic interactions with wetlands. Many factors control the propagation of surge in these natural systems including storm characteristics, storm-induced hydrodynamics, landscape complexity, vegetation biomechanical properties and the interactions of these different factors. While previous <span class="hlt">field</span> studies have largely focused on the impact of vegetation characteristics on attenuation processes, few have been undertaken with holistic consideration of these factors and their interactions. To bridge this gap of in-situ <span class="hlt">field</span> data and to support the calibration of storm surge and wave numerical models such that wetlands can be correctly parametrized on a <span class="hlt">regional</span> scale, we are carrying out high resolution surveys of hydrodynamics (pressure, current intensity and direction), morphology (topo-bathymetry, micro-topography) and vegetation (e.g. stem density, height, vegetation frontal area) in 4 marshes along the Chesapeake Bay. These areas are representative of the ecosystems and morphodynamic functions present in this <span class="hlt">region</span>, from the tidal Potomac marshes to the barrier-island back-bays of the Delmarva Peninsula. The <span class="hlt">field</span> monitoring program supports the investigation of the influence of different types of vegetation on water level, swell and wind wave attenuation and morphological evolution during storm surges. This dataset is also used to calibrate and validate numerical simulations of hurricane storm surge propagation at <span class="hlt">regional</span> and local scales and to support extreme weather coastal resilience planning in the <span class="hlt">region</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFMSA11B3946Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFMSA11B3946Y&link_type=ABSTRACT"><span id="translatedtitle">Statistical characteristics of nighttime mid-latitude F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities observed by Daejeon VHF coherent scattering radar in South Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, T. Y.; Kwak, Y. S.; Kil, H.; Lee, Y.; Lee, W. K.; Park, Y. D.</p> <p>2014-12-01</p> <p>We report statistical characteristics of mid-latitude nighttime F-<span class="hlt">region</span> <span class="hlt">field</span>-aligned irregularities (FAIs) based on more than three-year observations by Daejeon VHF coherent backscatter radar. This radar has built at Daejeon (36.18°N, 127.14°E, dip lat. 26.7°N) in 2009 with 40.8 MHz operating frequency for continuous monitoring of the behavior of electron density irregularities in the middle latitude. By using long-term observations from January 2010 to December 2013, we obtained the annual, diurnal and seasonal characteristics of a variety of a percentage occurrence, signal-to-noise ratio, and Doppler velocities from the nighttime F-<span class="hlt">region</span> irregularities over Korea peninsular. From almost four-year observations, the F-<span class="hlt">region</span> nighttime irregularities occurred most frequently during post-sunset period. These nighttime irregularities usually appeared with occupying different height levels according to local time. This height variation of F-<span class="hlt">region</span> FAIs was correlated with hmf2 of ionosonde in Icheon, South Korea. The irregularities were least active near the winter solstice and most active near summer solstice. From the annual occurrence variations, F-<span class="hlt">region</span> nighttime irregularities seem to have tendency with solar activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5849411','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5849411"><span id="translatedtitle">An integrated exploration model for Council Run <span class="hlt">field</span> analogs: <span class="hlt">Regional</span> geology and seismic stratigraphy of Devonian 6th Elk sandstones</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kelleher, G.; Johnson, R. )</p> <p>1991-08-01</p> <p>A geologic study of the Devonian Lock Haven 6th Elk formation along the structural front of Pennsylvania and Maryland suggest that present-day structures were active at the time of deposition. These structures barred deposition to the west and helped to localize sands in a northeast-southwest fairway. The 6th Elk sandstones occur in two major depositional lobes (located in Centre and Somerset counties in Pennsylvania, and Garret County, Maryland) and were deposited on a shallow-marine shelf by turbidity currents and later modified by storm-generated currents. Deposition of 6th Elk sands may also have been influenced by cross-strike discontinuities. A seismic study of the Council Run <span class="hlt">field</span> aids in subsurface identification of the 6th Elk. A high-amplitude seismic anomaly across the Council Run <span class="hlt">field</span> is correlated with increasing san thickness. Two dimensional modeling suggests that the seismic response is extremely sensitive to specific acquisition and processing techniques including filter and phase variability. Additional attribute analysis integrates the seismic data with the forward models. This results in a predictive method for potentially identifying 6th Elk sandstone development from seismic data. Applying the results of the seismic modeling at Council Run <span class="hlt">field</span> to a seismic grid across the previously defined 6th Elk depositional fairway has identified many exploratory prospects in Lycoming and Bradford counties, Pennsylvania. This area coincides with the site of a third, previously documented, Upper Devonian depositional lobe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22227988','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22227988"><span id="translatedtitle">Simulation study of wave phenomena from the sheath <span class="hlt">region</span> in single frequency capacitively coupled plasma discharges; <span class="hlt">field</span> reversals and ion reflection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sharma, S.; Turner, M. M.</p> <p>2013-07-15</p> <p>Capacitively coupled radio-frequency (RF) discharges have great significance for industrial applications. Collisionless electron heating in such discharges is important, and sometimes is the dominant mechanism. This heating is usually understood to originate in a stochastic interaction between electrons and the electric <span class="hlt">fields</span>. However, other mechanisms may also be important. There is evidence of wave emission with a frequency near the electron plasma frequency, i.e., ω{sub pe}, from the sheath <span class="hlt">region</span> in collisionless capacitive RF discharges. This is the result of a progressive breakdown of quasi-neutrality close to the electron sheath edge. These waves are damped in a few centimeters during their propagation from the sheath towards the bulk plasma. The damping occurs because of the Landau damping or some related mechanism. This research work reports that the emission of waves is associated with a <span class="hlt">field</span> reversal during the expanding phase of the sheath. Trapping of electrons near to this <span class="hlt">field</span> reversal <span class="hlt">region</span> is observed. The amplitude of the wave increases with increasing RF current density amplitude J(tilde sign){sub 0} until some maximum is reached, beyond which the wave diminishes and a new regime appears. In this new regime, the density of the bulk plasma suddenly increases because of ion reflection, which occurs due to the presence of strong <span class="hlt">field</span> reversal near sheath <span class="hlt">region</span>. Our calculation shows that these waves are electron plasma waves. These phenomena occur under extreme conditions (i.e., higher J(tilde sign){sub 0} than in typical experiments) for sinusoidal current waveforms, but similar effects may occur with non-sinusoidal pulsed waveforms for conditions of experimental interest, because the rate of change of current is a relevant parameter. The effect of electron elastic collisions on plasma waves is also investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25223030','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25223030"><span id="translatedtitle">[Effect of tillage patterns on the structure of weed communities in oat <span class="hlt">fields</span> in the cold and arid <span class="hlt">region</span> of North China].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Li; Zhang, Li; Wu, Dong-Xia; Zhang, Jun-Jun</p> <p>2014-06-01</p> <p>In order to clarify the effects of tillage patterns on farmland weed community structure and crop production characteristics, based on 10 years location experiment with no-tillage, subsoiling and conventional tillage in the cold and arid <span class="hlt">region</span> of North China, and supplementary experiment of plowing after 10 years no-tillage and subsoiling, oat was planted in 2 soils under different tillage patterns, and <span class="hlt">field</span> weed total density, dominant weed types, weed diversity index, <span class="hlt">field</span> weed biomass and oats yield were measured. The results showed that the <span class="hlt">regional</span> weed community was dominated by foxtail weed (Setaira viridis); the weed density under long-term no-tillage was 2.20-5.14 times of tillage at different growing stages of oat, but there were no significant differences between conditional tillage and plowing after long-term no-tillage and subsoiling. <span class="hlt">Field</span> weed Shannon diversity indices were 0.429 and 0.531, respectively, for sandy chestnut soil and loamy meadow soil under no-tillage conditions, and <span class="hlt">field</span> weed biomass values were 1.35 and 2.26 times of plowing treatment, while the oat biomass values were only 2807.4 kg x hm(-2) and 4053.9 kg x hm(-2), decreased by 22.3% and 46.2%, respectively. The results showed that the weed community characteristics were affected by both tillage patterns and soil types. Long-term no-tillage farmland in the cold and arid <span class="hlt">region</span> of North China could promote the natural evolution of plant communities by keeping more perennial weeds, and the plowing pattern lowered the annual weed density, eliminated perennial weeds with shallow roots, and stimulated perennial weeds with deep roots. PMID:25223030</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Ap%26SS.350..459G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Ap%26SS.350..459G"><span id="translatedtitle">Study of simultaneous presence of DD and PP electric <span class="hlt">fields</span> during the geomagnetic storm of November 7-8, 2004 and resultant TEC variation over the Indian <span class="hlt">Region</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Galav, P.; Sharma, Shweta; Rao, S. S.; Veenadhari, B.; Nagatsuma, T.; Pandey, R.</p> <p>2014-04-01</p> <p>During very intense geomagnetic storm of November 7-8, 2004 simultaneous presence of storm time disturbance dynamo and eastward and westward directed prompt penetration electric <span class="hlt">fields</span> inferred from the ground based magnetometer data in the 75∘ E sector is presente