Science.gov

Sample records for 5-10 km depth

  1. Hydraulic fracturing in situ stress measurements to 2.1 km depth at Cajon Pass, California

    USGS Publications Warehouse

    Healy, J.H.; Zoback, M.D.

    1988-01-01

    Stress measurements to 2.1 km reveal stress changes with depth that cannot be explained by an elastic response to uniform crustal strain. The data at about 1 km depth suggest that the stress is limited by the frictional strength of rock and is perturbed at greater depths by faults which intersect the borehole. The stress data indicate that there is little or no right-lateral shear stress acting on planes parallel to the San Andreas Fault. -Authors

  2. The possible subduction of continental material to depths greater than 200 km.

    PubMed

    Ye, K; Cong, B; Ye, D

    2000-10-12

    Determining the depth to which continental lithosphere can be subducted into the mantle at convergent plate boundaries is of importance for understanding the long-term growth of supercontinents as well as the dynamic processes that shape such margins. Recent discoveries of coesite and diamond in regional ultrahigh-pressure (UHP) metamorphic rocks has demonstrated that continental material can be subducted to depths of at least 120 km (ref. 1), and subduction to depths of 150-300 km has been inferred from garnet peridotites in orogenic UHP belts based on several indirect observations. But continental subduction to such depths is difficult to trace directly in natural UHP metamorphic crustal rocks by conventional mineralogical and petrological methods because of extensive late-stage recrystallization and the lack of a suitable pressure indicator. It has been predicted from experimental work, however, that solid-state dissolution of pyroxene should occur in garnet at depths greater than 150 km (refs 6-8). Here we report the observation of high concentrations of clinopyroxene, rutile and apatite exsolutions in garnet within eclogites from Yangkou in the Sulu UHP metamorphic belt, China. We interpret these data as resulting from the high-pressure formation of pyroxene solid solutions in subducted continental material. Appropriate conditions for the Na2O concentrations and octahedral silicon observed in these samples are met at depths greater than 200 km. PMID:11048717

  3. Compositional mantle layering revealed by slab stagnation at ~1,000 km depth

    NASA Astrophysics Data System (ADS)

    Ballmer, M. D.; Nakagawa, T.; Schmerr, N. C.; Ritsema, J.; Motoki, M.

    2015-12-01

    Improved constraints on lower-mantle composition are fundamental to understand the accretion, differentiation and thermochemical evolution of our planet. Whereas cosmochemical arguments indicate that lower-mantle rocks may be enriched in Si relative to upper-mantle pyrolite, seismic tomography images suggest whole-mantle convection and efficient mantle mixing. This study reconciles cosmochemical and geophysical constraints using the stagnation of some slab segments at ~1,000 km depth as the key observation. Whereas slab stagnation at ~660 km depth is well explained by the effects of the spinel-perovskite endothermic phase transition, flattening of slabs in the uppermost lower mantle remains poorly understood. Through numerical modeling of subduction, we show that enrichment of the lower mantle in intrinsically dense basaltic heterogeneity can render slabs neutrally buoyant at ~1,000 km depth. Slab stagnation (at ~660 and ~1,000 km depth) as well as unimpeded slab sinking to great depths can only coexist as three different modes of slab sinking behavior on Earth if the basalt fraction is ~8% higher in the lower than in the upper mantle, equivalent to a lower-mantle Mg/Si of ~1.18. Geodynamic models demonstrate that such a moderate compositional gradient can be sustained by compositional filtering of both slabs and plumes as they cross the transition zone, and thus persist over billions of years of whole-mantle convection. Whereas basaltic heterogeneity tends to get trapped in the transition zone and ultimately sink into the lower mantle, harzburgitic heterogeneity tends to rise into the uppermost mantle.

  4. Seismic evidence of negligible water carried below 400-km depth in subducting lithosphere.

    PubMed

    Green, Harry W; Chen, Wang-Ping; Brudzinski, Michael R

    2010-10-14

    Strong evidence exists that water is carried from the surface into the upper mantle by hydrous minerals in the uppermost 10-12 km of subducting lithosphere, and more water may be added as the lithosphere bends and goes downwards. Significant amounts of that water are released as the lithosphere heats up, triggering earthquakes and fluxing arc volcanism. In addition, there is experimental evidence for high solubility of water in olivine, the most abundant mineral in the upper mantle, for even higher solubility in olivine's high-pressure polymorphs, wadsleyite and ringwoodite, and for the existence of dense hydrous magnesium silicates that potentially could carry water well into the lower mantle (deeper than 1,000 km). Here we compare experimental and seismic evidence to test whether patterns of seismicity and the stabilities of these potentially relevant hydrous phases are consistent with a wet lithosphere. We show that there is nearly a one-to-one correlation between dehydration of minerals and seismicity at depths less than about 250 km, and conclude that the dehydration of minerals is the trigger of instability that leads to seismicity. At greater depths, however, we find no correlation between occurrences of earthquakes and depths where breakdown of hydrous phases is expected. Lastly, we note that there is compelling evidence for the existence of metastable olivine (which, if present, can explain the distribution of deep-focus earthquakes) west of and within the subducting Tonga slab and also in three other subduction zones, despite metastable olivine being incompatible with even extremely small amounts of water (of the order of 100 p.p.m. by weight). We conclude that subducting slabs are essentially dry at depths below 400 km and thus do not provide a pathway for significant amounts of water to enter the mantle transition zone or the lower mantle.

  5. The High Arctic Magnetic High - The Geophysical Manifestation of a Large (1.36 x 10e6 km2) and Voluminous (5-10 x 10e6 km3) Igneous Province

    NASA Astrophysics Data System (ADS)

    Saltus, Richard; Oakey, Gordon; Miller, Elizabeth; Jackson, Ruth

    2013-04-01

    The High Arctic Magnetic High (HAMH) dominates the magnetic anomaly field of the Earth north of about 75°N; this magnetic domain consists of very high amplitude magnetic highs and lows with variable orientations. The HAMH is visible on satellite magnetic compilations (e.g., MF6) with anomaly amplitudes greater than 200 nT indicating it is a globally significant feature. The magnetic potential of this magnetic feature is a single large intensity high indicative of a large volume of magnetic material in the crust. The map area of this magnetic domain is roughly 1.36 x 10e6 km2. Geographically the HAMH lies within the Amerasian Basin adjacent to the Lomonosov Ridge, encompasses the region of the Alpha and Mendeleev Ridges, and extends beneath the northern portions of the Canada Basin. Ocean floor geomorphology, limited seismic and sonobouy data, sparse dredge samples, and dated samples from the perimeter of the Arctic Ocean are consistent with the interpretation of the HAMH as the geophysical manifestation of a Large Igneous Province. The designation "High Arctic Large Igneous Province (HALIP)" has been applied to portions of the Arctic perimeter based on geologic mapping and sampling. The designation "Alpha/Mendeleev Large Igneous Province (AMLIP)" has been applied to the offshore Alpha/Mendeleev region (e.g., Grantz et al., 2009) with boundaries defined, in large part, by magnetic anomaly patterns. We have constructed 2D and 3D models of the HAMH to investigate the structure and geometry of this significant crustal feature. We estimate the overall volume of magnetic material as between 5-10 x 10e6 km3. The area and volume of this feature are comparable with estimates for the Deccan Traps and the North Atlantic Igneous Province, but are significantly smaller than the Kerguellen or Ontong Java Plateaus (based on tables in Coffin and Eldholm, 1994). In detail we find significant correlation between shorter wavelength portions of this magnetic feature and the

  6. Seismic evidence against a mantle chemical discontinuity near 660 km depth beneath Izu-Bonin

    NASA Astrophysics Data System (ADS)

    Castle, John C.; Creager, Kenneth C.

    We analyze P-wave codas from 12 deep Izu-Bonin earthquakes recorded by hundreds of Western United States seismograph stations for evidence of small-amplitude phases caused by near-source mantle discontinuities. For nearly every event, the dominant phase in the coda is the result of an S-to-P conversion from a nearly horizontal discontinuity ranging in depth from 650 to 690 km. This is interpreted as a thermally depressed spinel to perovskite and magnesiowüstite phase transition. If the 660-km seismic discontinuity is also associated with a change in chemistry, it would be dynamically depressed by a subducting slab. We consistently see that there is no nearly horizontal discontinuity between 700 and 1000 km with shear wave velocity contrast exceeding 1%; this observation places constraints on the properties of a postulated chemical discontinuity separating the upper and lower mantles.

  7. Subduction of European continental crust to 70 km depth imaged in the Western Alps

    NASA Astrophysics Data System (ADS)

    Paul, Anne; Zhao, Liang; Guillot, Stéphane; Solarino, Stefano

    2015-04-01

    The first conclusive evidence in support of the burial (and exhumation) of continental crust to depths larger than 90 km was provided by the discovery of coesite-bearing metamorphic rocks in the Dora Maira massif of the Western Alps (Chopin, 1984). Since then, even though similar outcrops of exhumed HP/UHP rocks have been recognized in a number of collisional belts, direct seismic evidences for subduction of continental crust in the mantle of the upper plate remain rare. In the Western Alps, the greatest depth ever recorded for the European Moho is 55 km by wide-angle seismic reflection (ECORS-CROP DSS Group, 1989). In an effort to image the European Moho at greater depth, and unravel the very complex lithospheric structure of the W-Alps, we have installed the CIFALPS temporary seismic array across the Southwestern Alps for 14 months (2012-2013). The almost linear array runs from the Rhône valley (France) to the Po plain (Italy) across the Dora Maira massif where exhumed HP/UHP metamorphic rocks of continental origin were first discovered. We used the receiver function processing technique that enhances P-to-S converted waves at velocity boundaries beneath the array. The receiver function records were migrated to depth using 4 different 1-D velocity models to account for the strongest structural changes along the profile. They were then stacked using the classical common-conversion point technique. Beneath the Southeast basin and the external zones, the obtained seismic section displays a clear converted phase on the European Moho, dipping gently to the ENE from ~35 km at the western end of the profile, to ~40 km beneath the Frontal Penninic thrust (FPT). The Moho dip then noticeably increases beneath the internal zones, while the amplitude of the converted phase weakens. The weak European Moho signal may be traced to 70-75 km depth beneath the eastern Dora Maira massif and the westernmost Po plain. At shallower level (20-40 km), we observe a set of strong

  8. Compositional mantle layering revealed by slab stagnation at ~1000-km depth.

    PubMed

    Ballmer, Maxim D; Schmerr, Nicholas C; Nakagawa, Takashi; Ritsema, Jeroen

    2015-12-01

    Improved constraints on lower-mantle composition are fundamental to understand the accretion, differentiation, and thermochemical evolution of our planet. Cosmochemical arguments indicate that lower-mantle rocks may be enriched in Si relative to upper-mantle pyrolite, whereas seismic tomography images suggest whole-mantle convection and hence appear to imply efficient mantle mixing. This study reconciles cosmochemical and geophysical constraints using the stagnation of some slab segments at ~1000-km depth as the key observation. Through numerical modeling of subduction, we show that lower-mantle enrichment in intrinsically dense basaltic lithologies can render slabs neutrally buoyant in the uppermost lower mantle. Slab stagnation (at depths of ~660 and ~1000 km) and unimpeded slab sinking to great depths can coexist if the basalt fraction is ~8% higher in the lower mantle than in the upper mantle, equivalent to a lower-mantle Mg/Si of ~1.18. Global-scale geodynamic models demonstrate that such a moderate compositional gradient across the mantle can persist can in the presence of whole-mantle convection. PMID:26824060

  9. Compositional mantle layering revealed by slab stagnation at ~1000-km depth

    PubMed Central

    Ballmer, Maxim D.; Schmerr, Nicholas C.; Nakagawa, Takashi; Ritsema, Jeroen

    2015-01-01

    Improved constraints on lower-mantle composition are fundamental to understand the accretion, differentiation, and thermochemical evolution of our planet. Cosmochemical arguments indicate that lower-mantle rocks may be enriched in Si relative to upper-mantle pyrolite, whereas seismic tomography images suggest whole-mantle convection and hence appear to imply efficient mantle mixing. This study reconciles cosmochemical and geophysical constraints using the stagnation of some slab segments at ~1000-km depth as the key observation. Through numerical modeling of subduction, we show that lower-mantle enrichment in intrinsically dense basaltic lithologies can render slabs neutrally buoyant in the uppermost lower mantle. Slab stagnation (at depths of ~660 and ~1000 km) and unimpeded slab sinking to great depths can coexist if the basalt fraction is ~8% higher in the lower mantle than in the upper mantle, equivalent to a lower-mantle Mg/Si of ~1.18. Global-scale geodynamic models demonstrate that such a moderate compositional gradient across the mantle can persist can in the presence of whole-mantle convection. PMID:26824060

  10. Alpe Arami garnet peridotite from depth >300 km: revisited in 15 years (Invited)

    NASA Astrophysics Data System (ADS)

    Dobrzhinetskaya, L.; Lesher, C. E.; Bozhilov, K. N.; Green, H. W.

    2009-12-01

    In the mid-1990s we recognized that collisional orogenic belts with UHP metamorphic rocks of crustal affinities, might contain mantle peridotites uplifted from depths of >300km (Dobrzhinetsklaya et al., 1996). We proposed that ilmenite rods + chromite flakes in olivine are the result of exsolution, and that they imply high solubility of TiO2 in Ol at high P-T. The conclusion that the Alpe Arami peridotite massif originates from great depth remains controversial despite the subsequent discovery of Cpx inclusions in Grt containing exsolution lamellae of clinoenstatite displaying antiphase domains. The latter observation requires that the originally precipitated pyroxene had a high-pressure C2/c space group structure consistent with an origin from >8 GPa (~250 km) (Bozhilov et al., 1999). We used confocal laser scanning microscopy to obtain quantitative 3D measurements of Ilm abundance in Ol. We find that Ilm rods can reach >1 vol. % in Ol supporting our contention that Ilm rods exsolved from olivine at 9-12 GPa, e.g. >300 km (Bozhilov et al., 2003). Arguments that Ilm rods hosted by Ol are reaction products from the breakdown of Ti-clinohumite (Risold et al., 2003) are unconvincing given that Ti-clinohumite breakdown does not produce Ilm + chromite that are characteristic of Alpe Arami olivine. Likewise, we have confirmed the high solubility of Ti in olivine at high P-T conditions in multianvil experiments (Dobrzhinetskaya et al., 2000) - findings that are strengthened by the experiments of Tinker & Lesher (2001). Using Focused Ion Beam we prepared TEM foils of the later experiments and confirm that the concentration of TiO2 in Ol increases with pressure under nearly isothermal conditions. Two reactions are proposed to account for these observations. If Ti enters the octahedral site of olivine, either an oxide phase must be formed or a phase richer in SiO2 than olivine must be consumed, leading to reaction 1: 6MgSiO3 + 2FeTiO3 = 2Ti△SiO4 + 3Mg2SiO4 + Fe2SiO4 [1

  11. Observations of earthquake source parameters at 2 km depth in the Long Valley Caldera, eastern California

    USGS Publications Warehouse

    Prejean, Stephanie G.; Ellsworth, William L.

    2001-01-01

    To investigate seismic source parameter scaling and seismic efficiency in the Long Valley caldera, California, we measured source parameters for 41 earthquakes (M 0.5 to M 5) recorded at 2 km depth in the Long Valley Exploratory Well. Borehole recordings provide a wide frequency bandwidth, typically 1 to 200–300 Hz, and greatly reduce seismic noise and path effects compared to surface recordings. We calculated source parameters in both the time and frequency domains for P and S waves. At frequencies above the corner frequency, spectra decay faster than ω3, indicating that attenuation plays an important role in shaping the spectra (path averaged Qp = 100–400, Qs = 200–800). Source parameters are corrected for attenuation and radiation pattern. Both static stress drops and apparent stresses range from approximately 0.01 to 30 MPa. Although static stress drops do not vary with seismic moment for these data, our analyses are consistent with apparent stress increasing with increasing moment. To estimate tectonic driving stress and seismic efficiencies in the region, we combined source parameter measurements with knowledge of the stress field and a Coulomb failure criterion to infer a driving stress of 40–70 MPa. Subsequent seismic efficiencies are consistent with McGarr's (1999) hypothesis of a maximum seismic efficiency of 6%.

  12. Detection of Postseismic Crustal Movement of an Earthquake with Focal Depth Exceeding 650 km

    NASA Astrophysics Data System (ADS)

    Heki, K.; Mitsui, Y.

    2013-12-01

    Although a deep-focus earthquake often causes strong ground shaking due to low attenuation of seismic waves propagating through the subducting slab, it never leaves permanent deformation of the surface detectable with GPS. Here we report that a deep earthquake on August 14, 2012 (Mw 7.7, focal depth 654 km) beneath Sakhalin has been causing postseismic crustal movements in Hokkaido exceeding a centimeter by a hitherto unknown mechanism. Heki and Mitsui (EPSL 2013) found landward movements of GPS stations to have accelerated on segments adjacent to those ruptured in the 2003 Tokachi-Oki (Mw8.0) and the 2011 Tohoku-Oki (Mw9.0) earthquakes in NE Japan. Sea floor GPS measurements by Japan Coast Guard also revealed post-2011 landward movement of MYG1 as fast as ~30 cm per year. From these observations, we inferred that the subduction of the Pacific Plate slab was significantly accelerated (1.5 and 3 times) after the two interplate earthquakes. During interseismic periods, the balance between the up-dip (viscous resistance and interplate coupling) and down-dip (slab pull and ridge push) forces realizes constant subduction rate. A megathrust event reduces interplate coupling, and let down-dip force temporarily exceed the other one, resulting in the accelerated subduction under the new balance attained by increased viscous resistance. Accelerated regime would be temporary and the geological rate will resume as interplate coupling recovers. We newly found that the landward movements of GPS stations in the eastern Hokkaido have undergone small but distinct acceleration of up to 1 cm/year in conjunction with the 2012 August deep-focus earthquake. Within-slab seismicity of down-dip compression mechanisms is activated in the deep part of subducting slabs after megathrust events (Lay et al., PEPI 1989), due possibly to the increased edge resistance caused by the slab acceleration. The 2012 deep earthquake occurred close to the down-dip end of the straight part of the Pacific

  13. A metagenomic window into carbon metabolism at 3 km depth in Precambrian continental crust.

    PubMed

    Magnabosco, Cara; Ryan, Kathleen; Lau, Maggie C Y; Kuloyo, Olukayode; Sherwood Lollar, Barbara; Kieft, Thomas L; van Heerden, Esta; Onstott, Tullis C

    2016-03-01

    Subsurface microbial communities comprise a significant fraction of the global prokaryotic biomass; however, the carbon metabolisms that support the deep biosphere have been relatively unexplored. In order to determine the predominant carbon metabolisms within a 3-km deep fracture fluid system accessed via the Tau Tona gold mine (Witwatersrand Basin, South Africa), metagenomic and thermodynamic analyses were combined. Within our system of study, the energy-conserving reductive acetyl-CoA (Wood-Ljungdahl) pathway was found to be the most abundant carbon fixation pathway identified in the metagenome. Carbon monoxide dehydrogenase genes that have the potential to participate in (1) both autotrophic and heterotrophic metabolisms through the reversible oxidization of CO and subsequent transfer of electrons for sulfate reduction, (2) direct utilization of H2 and (3) methanogenesis were identified. The most abundant members of the metagenome belonged to Euryarchaeota (22%) and Firmicutes (57%)-by far, the highest relative abundance of Euryarchaeota yet reported from deep fracture fluids in South Africa and one of only five Firmicutes-dominated deep fracture fluids identified in the region. Importantly, by combining the metagenomics data and thermodynamic modeling of this study with previously published isotopic and community composition data from the South African subsurface, we are able to demonstrate that Firmicutes-dominated communities are associated with a particular hydrogeologic environment, specifically the older, more saline and more reducing waters. PMID:26325359

  14. A metagenomic window into carbon metabolism at 3 km depth in Precambrian continental crust.

    PubMed

    Magnabosco, Cara; Ryan, Kathleen; Lau, Maggie C Y; Kuloyo, Olukayode; Sherwood Lollar, Barbara; Kieft, Thomas L; van Heerden, Esta; Onstott, Tullis C

    2016-03-01

    Subsurface microbial communities comprise a significant fraction of the global prokaryotic biomass; however, the carbon metabolisms that support the deep biosphere have been relatively unexplored. In order to determine the predominant carbon metabolisms within a 3-km deep fracture fluid system accessed via the Tau Tona gold mine (Witwatersrand Basin, South Africa), metagenomic and thermodynamic analyses were combined. Within our system of study, the energy-conserving reductive acetyl-CoA (Wood-Ljungdahl) pathway was found to be the most abundant carbon fixation pathway identified in the metagenome. Carbon monoxide dehydrogenase genes that have the potential to participate in (1) both autotrophic and heterotrophic metabolisms through the reversible oxidization of CO and subsequent transfer of electrons for sulfate reduction, (2) direct utilization of H2 and (3) methanogenesis were identified. The most abundant members of the metagenome belonged to Euryarchaeota (22%) and Firmicutes (57%)-by far, the highest relative abundance of Euryarchaeota yet reported from deep fracture fluids in South Africa and one of only five Firmicutes-dominated deep fracture fluids identified in the region. Importantly, by combining the metagenomics data and thermodynamic modeling of this study with previously published isotopic and community composition data from the South African subsurface, we are able to demonstrate that Firmicutes-dominated communities are associated with a particular hydrogeologic environment, specifically the older, more saline and more reducing waters.

  15. Large-scale hydraulic structure of a seismogenic fault at 10 km depth (Gole Larghe Fault Zone, Italian Southern Alps)

    NASA Astrophysics Data System (ADS)

    Bistacchi, Andrea; Di Toro, Giulio; Smith, Steve; Mittempergher, Silvia; Garofalo, Paolo

    2014-05-01

    The definition of hydraulic properties of fault zones is a major issue in structural geology, seismology, and in several applications (hydrocarbons, hydrogeology, CO2 sequestration, etc.). The permeability of fault rocks can be measured in laboratory experiments, but its upscaling to large-scale structures is not straightforward. For instance, typical permeability of fine-grained fault rock samples is in the 10-18-10-20 m2 range, but, according to seismological estimates, the large-scale permeability of active fault zones can be as high as 10-10 m2. Solving this issue is difficult because in-situ measurements of large-scale permeability have been carried out just at relatively shallow depths - mainly in oil wells and exceptionally in active tectonic settings (e.g. SAFOD at 3 km), whilst deeper experiments have been performed only in the stable continental crust (e.g. KTB at 9 km). In this study, we apply discrete fracture-network (DFN) modelling techniques developed for shallow aquifers (mainly in nuclear waste storage projects like Yucca Mountain) and in the oil industry, in order to model the hydraulic structure of the Gole Larghe Fault Zone (GLFZ, Italian Southern Alps). This fault, now exposed in world-class glacier-polished outcrops, has been exhumed from ca. 8 km, where it was characterized by a well-documented seismic activity, but also by hydrous fluid flow evidenced by alteration halos and precipitation of hydrothermal minerals in veins and along cataclasites. The GLFZ does not show a classical seal structure that in other fault zones corresponds to a core zone characterized by fine-grained fault rocks. However, permeability is heterogeneous and the permeability tensor is strongly anisotropic due to fracture preferential orientation. We will show with numerical experiments that this hydraulic structure results in a channelized fluid flow (which is consistent with the observed hydrothermal alteration pattern). This results in a counterintuitive situation

  16. XCT quantified: a multiscale roughness study of fractures and veins in Pomeranian shale on samples collected at 4 km depth

    NASA Astrophysics Data System (ADS)

    Pluymakers, Anne; Renard, Francois

    2016-04-01

    In low-permeability rocks, such as shale, fractures are an important control on permeability, where the formation permeability will be a combination of matrix permeability plus that of the natural and induced fractures. We obtained shale samples from borehole material, originating at 4 km depth in the Polish Pomeranian basin. They consist of 40-60% illite plus mica, 1-10% organic matter, 10% chlorite, 10% carbonates, plus minor amounts of K-feldspar, plagioclase and kaolinite. There are many bedding-parallel fractures present in the retrieved core material, as well as bedding-parallel carbonate-rich veins. The existence and origin of these fractures at depth is debated, as they could have formed as well during drilling plus exhumation of the borehole samples. However, vein formation occurs at depth, and as such the topography of the vein-rock interface is preserved even upon sample extraction. We have imaged 4 samples in 3D using X-ray microtomography performed on a laboratory tomograph. One sample was also analyzed on the beamline ID19 at the European Synchrotron Radiation Facility, with final voxel spatial sizes ranging between 0.6-26 micrometers, thus allowing a multi-scale analysis of fractures and veins. The shape and aperture of the fractures and veins have been extracted in 3D. Fluid flow is controlled by fracture aperture plus the surface roughness of the fracture wall. Hence, fracture and vein roughness plus their spatial scaling properties are characterized using the Hurst exponent H. At low resolution (11-26 μm per voxel) there is a small difference in Hurst exponents parallel or perpendicular to the bedding, but on average veins exhibit H = 0.47, and cracks H = 0.35. Thus, veins exhibit more texture than cracks. This may be related to a different aperture mechanism, or to a characteristic 'grain size' present in the vein fill material. The sample scanned at multiple resolutions showed that an increase in resolution leads to an increase in the Hurst

  17. Earthquake source scaling relationships from -1 to 5 ML using seismograms recorded at 2.5-km depth

    NASA Astrophysics Data System (ADS)

    Abercrombie, Rachel E.

    1995-12-01

    The scaling relationships of earthquake sources less than about magnitude 3 have been the subject of considerable controversy over the last two decades. Studies of such events have shown a tendency for the constant stress drop, self similarity of larger earthquakes to breakdown at small magnitudes, and an apparent minimum source dimension of about 100 m has been observed. Other studies showed that this apparent breakdown in scaling could be an artifact of severe near-surface attenuation, limiting the spatial resolution of surface data. In this study, source parameters are determined for over 100 nearby, tectonic earthquakes, from recordings at a depth of 2.5 km (in granite) in the Cajon Pass scientific drill hole, southern California. Comparison of the seismograms recorded at this depth with those at the wellhead clearly demonstrates the effect of the severe attenuation in the upper kilometers of the Earth's crust. Source parameters are calculated by spectral modeling of three-component P and S waves, assuming four source models based on the Brune ω-2 (n = 2) model. In model l, n = 2 is fixed, and Q of P and S waves is determined to be 912 (581-1433) and 1078 (879-1323), respectively (the numbers in parentheses are ±1 standard deviation). In model 2, QP = QS = 1000 is assumed and n is allowed to vary. The ω-2 model is a good average for the data set, but there is some real scatter supported by the data. In model 3, QP = QS = 1000 is also assumed and ω-2 is constrained, and in model 4, attenuation is ignored and n is allowed to vary. Source dimensions of less than 10m are observed for all four models, 10 times smaller than the proposed "minimum". No breakdown in constant stress drop scaling is seen in the downhole data (approximately ML-1 to 5.5, M0 = 109 - 1016 Nm). The ratio between radiated seismic energy (estimated by integrating the velocity squared spectra with adequate signal bandwidth) and seismic moment appears to decrease gradually with decreasing

  18. A discussion on “The 410-km-depth discontinuity: A sharpness estimate from near-critical reflections” by Vidale et al.

    NASA Astrophysics Data System (ADS)

    Krishna, V. G.; Ramesh, D. S.

    Vidale et al. [1995] presented a convincing evidence of a fairly sharp ‘410-km’ seismic discontinuity uncjer the western United States by examining clear noise-free reflected arrivals from this discontinuity in the near-critical distance range of 11.5° to 14° (Fig. Ia). They reconstructed the P velocity-depth model from the arrival times of the 410-km reflection and initial P waves across the distance range 8°-14°. The prominent features of the upper mantle P velocity model given by them include; a low velocity layer (LVL) in the depth range of about 110-200 km with a broad transitional bottom, a fairly large velocity gradient (0.4 km/s velocity increase from 200 to 410 km depth) above the 410-km discontinuity which is sharp and associated with a 5.5% velocity increase.Seismic estimates of sharpness as well as velocity contrast at the ‘410-km’ and ‘660-km’ discontinuities in the mantle transition zone provide important constraints to plausible models of composition, temperature and convective processes in the deep earth. The rapid increases of seismic wave velocities inferred in the transition zone, at depths of 410-Km and 660-km, are classically associated [Ringwood, 1975] with the pressure-induced phase transitions in Olivine which is considered to be the predominant mineral in the upper mantle. Recent observations of high quality coherent seismic reflections from the transition zone [Benz and Vidale, 1993; Vidale et al., 1995] conclusively reveal that the 410-km discontinuity is fairly sharp. Contrastingly the experimental results from mineral physics [Akaogi et al., 1989; Bina and Wood, 1987; Katsura and Ito, 1989] predict a substantially larger transition width, on the order of 6-19 km for the olivine-beta spinel phase transition at pressures corresponding to 410-km-depth discontinuity. Similar inconsistencies in the magnitude of velocity contrast at the 410-km discontinuity are also found [Duffy et al., 1995; Jeanloz, 1995] by comparison of

  19. Observations in variations in the amplitude and depths of the 410 and 520 km discontinuities from PdP and SdS bounce point studies.

    NASA Astrophysics Data System (ADS)

    Darensburg, A.; Ainiwaer, A.; Gurrola, H.

    2015-12-01

    To gain a better understanding of the upper mantle transition zone, we beamform EarthScope Transportable array data of events from the western Pacific ring of fire to produce relatively high frequency (0.75 Hz) PdP functions (underside P reflections from a depth d) of the mantle beneath the central Pacific from the society Islands across the Aleutian trench. Like most PdP studies, we fail to image the 660 km discontinuity so we focus on the 410, and 520. It is believed that the 410 and 520 km discontinuities are the result of exothermic phase changes in the Olivine mineral system at pressure and temperatures consistent with the indicated depths. Because these boundaries are hypothesized to be exothermic, we expect them to be deeper in hot regions and shallow in cool. Modeling of these boundaries by mineral physicists suggest the 410 occurs over a 10 km interval and the 520 over about 30 km. Our observed amplitudes of P410P as a function of frequency compared to waveform modeling indicate that the 410 phase change must occur over less 6 km. Our observations of a strong 520 km discontinuity at 0.75 Hz also suggests that this velocity contrast occurs over less than 10 km rather than the hypothesized 30 km. We found that the average depth to the 410 km discontinuity across our study area to be 420 km to 425km. The 520 km discontinuity appears to be strongest around Hawaii and north of the Aleutian trench. The depths of the P410P and P520P phases appear to be correlated in most areas where they occur together; deepest the north of the Aleutian trench and southwestern Alaska; and shallowest south of the westernmost Aleutian trench. One of the more surprising observations was that the P520P phase appears to be the smallest or not observable in regions with the strongest P410P phase. SdS observations will be added to this study for the AGU meeting.

  20. A review of controlled-source electromagnetic science applications and opportunities for imaging in the depth range 20 m to 1 km (Invited)

    NASA Astrophysics Data System (ADS)

    Everett, M. E.

    2009-12-01

    There are many exciting geoscience opportunities available to those who can provide three—dimensional subsurface characterization within the 20 m—1.0 km depth range. Applications include gas hydrates and permafrost; climate change proxy signatures in the stratigraphic record; shoreline shaping processes; glacier and ice—sheet mass transport; watershed—scale and coastal hydrology including seawater intrusion; fault—zone characterization; Earth’s tectonic, volcanic, and extraterrestrial impact history; landslide hazard assessment; carbon sequestration; characterization of geothermal systems. Many of the aforementioned science applications can and have been addressed using various geophysical techniques. The shallower depth range is very suitable to multi—electrode resistivity imaging, which has seen a tremendous resurgence of late thanks to newly developed instrumentation. Ground—penetrating radar signals provide high—resolution subsurface images but they attenuate rapidly with depth and hence, except in special cases, do not probe beneath 20 m. Seismic reflection and refraction studies, using artificial sources, earthquakes and ambient noise, supplemented with newer surface wave and interferometric methods, are the traditional workhorse for the 20 m - 1.0 km depth range. Gravity and magnetic techniques continue to see great improvements and have long provided valuable subsurface information, when either used alone or in conjunction with another method. Other geophysical techniques such as spontaneous potential, induced polarization, and electroseismic are also gaining in importance. Controlled—source electromagnetics occupies an important niche for 20 m -1.0 km depth investigations as a complement to seismic and as an active technique that permits both parametric (variable frequency, or time—domain equivalent) and geometric (variable source—receiver separations) soundings. Low—frequency (sub—kHz) electromagnetic induction signals

  1. Microstructural investigation of a locally mirror-like surface collected at 4 km depth in a Pomeranian shale sample

    NASA Astrophysics Data System (ADS)

    Pluymakers, Anne; Renard, Francois

    2016-04-01

    The presence of shiny sliding surfaces, or mirror surfaces, is sometimes thought to have been caused by slip at seismic velocities. Many fault mirrors reported so far are described to occur in carbonate-rich rocks. Here we present microstructural data on a mirror-like slip surface in the Pomeranian shale, recovered from approximately 4 km depth. The accommodated sliding of this fault is probably small, not more than one or two centimeter. The Pomeranian shale is a dark-grey to black shale, composed of 40-60% illite plus mica, 1-10% organic matter, 10% chlorite, and 10 % carbonates plus minor amounts of K-feldspar, plagioclase and kaolinite. In this sample, the surface is optically smooth with striations and some patches that reflect light. Observations using a Hitachi TM3000 (table-top) SEM show that the striations are omnipresent, though more prominent in the carbonate patches (determined using EDS analysis). The smooth surface is locally covered by granular material with a grain size up to 10 μm. This is shown to consist of a mixture of elements and thus likely locally derived fault gouge. The clay-rich parts of the smooth surface are equidimensional grains, with sub-micron grain sizes, whereas in the unperturbed part of the shale core the individual clay platelets are easy to distinguish, with lengths up to 10 μm. The striated calcite-rich patches appear as single grains with sizes up to several millimeters, though they occasionally are smeared out in a direction parallel to the striations. We have analyzed surface roughness at magnifications of 2.5x to 100x using a standard White Light Interferometer, parallel and perpendicular to slip. At low magnifications, 2.5x and 5x, Hurst exponents were anomalously low, around 0.1 to 0.2, interpreted to be related to a lack of sufficient resolution to pick up the striations. At higher magnification the Hurst exponent is 0.34 to 0.43 parallel to the striation, and 0.44 to 0.61 perpendicular to the striation. This

  2. Time-temperature-burial significance of Devonian anthracite implies former great (approx. 6. 5 km) depth of burial of Catskill Mountains, New York

    SciTech Connect

    Friedman, G.M.; Sanders, J.E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Catskill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190/sup 0/C. Using a geothermal gradient of 26/sup 0/C.km/sup -1/ (17/sup 0/F.1,000 ft/sup -1/), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26/sup 0/C.km/sup -1/ imply a temperature of 307/sup 0/C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170/sup 0/C.km/sup -1/, which would have subjected the base of the Paleozoic to a temperature of 955/sup 0/GAMMA, which is far higher than the 600 to 650/sup 0/C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  3. Influence of a component of solar irradiance on radon signals at 1 km depth, Gran Sasso, Italy

    NASA Astrophysics Data System (ADS)

    Steinitz, G.; Piatibratova, O.; Charit-Yaari, N.

    2012-12-01

    Exploratory monitoring of radon is conducted at one location at the deep underground Gran Sasso National Laboratory (LNGS). Measurements (15-min resolution) are performed over a time span of ca. 600 days in the air of the surrounding calcareous country rock. Utilizing both alpha and gamma-ray detectors systematic and recurring radon signals are recorded. Two primary signal types are determined: (a) non-periodic Multi-Day (MD) signals lasting 2-10 days, and (b) Daily Radon (DR) signals - which are of a periodic nature exhibiting a primary 24-h cycle. The local ancillary environmental conditions (P, T) seem not to affect radon in air monitored at the site. Long term patterns of day-time measurements are different from the pattern of night-time measurements indicating a day-night modulation of gamma radiation from radon in air. The phenomenology of the MD and DR signals is similar to situations encountered at other locations where radon is monitored with a high time resolution in geogas at upper crustal levels. In accordance with recent field and experimental results it is suggested that a components of solar irradiance is affecting the radiation from radon in air, and this influence is further modulated by the diurnal rotation of Earth. The occurrence of these radon signals in the 1 km deep low radiation underground geological environment of LNGS provides new information on the time variation of the local radiation environment. The observations and results place the LNGS facility as a high priority location for performing advanced investigations of these geophysical phenomena, due to its location and its infrastructure.

  4. Influence of a component of solar irradiance on radon signals at 1 km depth, Gran Sasso, Italy

    PubMed Central

    Steinitz, G.; Piatibratova, O.; Gazit-Yaari, N.

    2013-01-01

    Exploratory monitoring of radon is conducted at one location in the deep underground Gran Sasso National Laboratory (LNGS). Measurements (15-min resolution) are performed over a time span of ca 600 days in the air of the surrounding calcareous country rock. Using both α- and γ-ray detectors, systematic and recurring radon signals are recorded. Two primary signal types are determined: (i) non-periodic multi-day (MD) signals lasting 2–10 days and (ii) daily radon (DR) signals—which are of a periodic nature exhibiting a primary 24-h cycle (θ=0.48). The local ancillary environmental conditions (pressure, temperature) seem not to affect radon in air monitored at the site. Long-term patterns of daytime measurements are different from the pattern of night-time measurements indicating a day–night modulation of γ-radiation from radon in air. The phenomenology of the MD and DR signals is similar to situations encountered at other locations where radon is monitored with a high time resolution in geogas at upper crustal levels. In accordance with recent field and experimental results, it is suggested that a component of solar irradiance is affecting the radiation from radon in air, and this influence is further modulated by the diurnal rotation of the Earth. The occurrence of these radon signals in the 1 km deep low-radiation underground geological environment of LNGS provides new information on the time variation of the local radiation environment. The observations and results place the LNGS facility as a high-priority location for performing advanced investigations of these geophysical phenomena. PMID:24204189

  5. Influence of a component of solar irradiance on radon signals at 1 km depth, Gran Sasso, Italy.

    PubMed

    Steinitz, G; Piatibratova, O; Gazit-Yaari, N

    2013-11-01

    Exploratory monitoring of radon is conducted at one location in the deep underground Gran Sasso National Laboratory (LNGS). Measurements (15-min resolution) are performed over a time span of ca 600 days in the air of the surrounding calcareous country rock. Using both α- and γ-ray detectors, systematic and recurring radon signals are recorded. Two primary signal types are determined: (i) non-periodic multi-day (MD) signals lasting 2-10 days and (ii) daily radon (DR) signals-which are of a periodic nature exhibiting a primary 24-h cycle (θ=0.48). The local ancillary environmental conditions (pressure, temperature) seem not to affect radon in air monitored at the site. Long-term patterns of daytime measurements are different from the pattern of night-time measurements indicating a day-night modulation of γ-radiation from radon in air. The phenomenology of the MD and DR signals is similar to situations encountered at other locations where radon is monitored with a high time resolution in geogas at upper crustal levels. In accordance with recent field and experimental results, it is suggested that a component of solar irradiance is affecting the radiation from radon in air, and this influence is further modulated by the diurnal rotation of the Earth. The occurrence of these radon signals in the 1 km deep low-radiation underground geological environment of LNGS provides new information on the time variation of the local radiation environment. The observations and results place the LNGS facility as a high-priority location for performing advanced investigations of these geophysical phenomena.

  6. Time-temperature-burial significance of Devonian anthracite implies former great (˜6.5 km) depth of burial of Catskill Mountains, New York

    NASA Astrophysics Data System (ADS)

    Friedman, Gerald M.; Sanders, John E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Cat-skill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. A similar degree of thermal activity is implied by the black color (Staplin kerogen-alteration index of 4) of the associated (possibly recycled) carbonized kerogen, a conodont-alteration index of 4, and authigenic chlorite and local sericite fillings of the former interparticle pores of interbedded sandstones. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190 °C. Using a geothermal gradient of 26 °C · km-1 (17 °F · 1,000 ft-1), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26 °C · km-1 imply a temperature of 307 °C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170 °C · km-1, which would have subjected the base of the Paleozoic to a temperature of 955 °C, which is far higher than the 600 to 650 °C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  7. Ultra-low co-seismic stiffness of fault rocks at seismogenic (8-11 km) depth

    NASA Astrophysics Data System (ADS)

    Griffith, W. A.; Mitchell, T. M.; Di Toro, G.; Renner, J.

    2011-12-01

    During the seismic cycle, elastic stiffness limits the amount of elastic strain energy stored in the wall rocks bordering a fault. Elastic stiffness of fault zone rocks is expected to be highly variable during the seismic cycle due to complicated damage and healing processes. In addition to longer-term alteration which may take place during exhumation, it is impossible to assess how well rock stiffness as measured in the laboratory represents in situ, coseismic rock stiffness at seismogenic depths. Here we estimate the in situ, coseismic rock stiffness of fault rocks from the pseudotachylyte-bearing Gole Larghe Fault Zone of the Adamello Batholith, Italian Southern Alps, using aspect ratio measurements of pseudotachylyte injection veins and numerical Displacement Discontinuity Method simulations. Aspect ratios of over 100 pseudotachylyte injection veins which cut across tonalite, cataclasite, or aplite show that maximum vein aperture is linearly related to vein length. To model vein opening, the fault and the injection vein are assumed to be filled with melt that has a fluid pressure P. Consistent with recent results from modeling of melt lubrication we assume that the magnitude of the fluid pressure P is exactly the same as the fault-normal normal stress such that the fault vein approximately maintains constant thickness during slip (i.e. melt extrusion exactly balances melt production). This model assumes that melt is injected into the sidewall without significant fluid overpressure, taking advantage of pre-existing planes of weakness and transiently reduced fault-parallel normal stress in the wake of the earthquake rupture tip. Numerical simulations of injection vein opening due to fluid pressure of frictional melt indicate that the average in situ coseismic stiffness of the fault rocks ranged from 2-15 GPa, about a factor of two less than typical laboratory measurements of the same rocks, and the stiffness of tonalite and cataclasite are markedly different.

  8. Anatomy of an ancient subduction interface at 40 km depth: Insights from P-T-t-d data, and geodynamic implications (Dent Blanche, Western Alps)

    NASA Astrophysics Data System (ADS)

    Angiboust, Samuel; Glodny, Johannes; Oncken, Onno; Chopin, Christian

    2014-05-01

    An exhumed metamorphic suture zone over 40 km long is exposed in the Dent Blanche Region of the Western Alps belt, along the Swiss-Italian border. In this region, the metasediment-bearing ophiolitic remnants of the Liguro-Piemontese ocean (Tsaté complex) are overthrusted by a continental, km-sized complex (Dent Blanche Tectonic System: DBTS) of Austro-Alpine affinity. The DBTS represents a strongly deformed composite terrane with independent tectonic slices of continental and oceanic origin. In order to better understand the nature and the geodynamic meaning of the shear zone at the base of the DBTS (Dent Blanche Thrust, DBT) we re-evaluated the pressure-temperature-time-deformation (P-T-t-d) history of these two units using modern thermobarometric tools, Rb/Sr deformation ages and field relationships. Our results show that the Tsaté complex is formed by a stack of km-thick calcschists-bearing tectonic slices, having experienced variable maximum burial temperatures of between 360°C and 490°C at depths of ca. 25-40 km, between 41 Ma and 37 Ma. The Arolla gneissic mylonites constituting the base of the DBTS experienced a continuous record of protracted high-pressure (12-14 kbar), top-to-NW D1 deformation at 450-500°C between 43 and 55 Ma. Some of these primary, peak metamorphic fabrics have been sheared (top-to-SE D2) and backfolded during exhumation and collisional overprint (20 km depth, 35-40 Ma) leading to the regional greenschist facies retrogression particularly prominent within Tsaté metasediments. The final juxtaposition of the DBTS with the Tsaté complex occurred between 350 and 500°C during this later, exhumation-related D2 event. Although some exhumation-related deformation partially reworked D1 primary features, we emphasize that the DBT can be viewed as a remnant of the Alpine early Eocene blueschist-facies subduction interface region. The DBT therefore constitutes the deeper equivalent of some shallower portions of the Alpine subduction

  9. Formation of continental crust in a temporally linked arc magma system from 5 to 30 km depth: ~ 90 Ma plutonism in the Cascades Crystalline Core composite arc section

    NASA Astrophysics Data System (ADS)

    Ratschbacher, B. C.; Miller, J. S.; Kent, A. J.; Miller, R. B.; Anderson, J. L.; Paterson, S. R.

    2015-12-01

    Continental crust has an andesitic bulk composition with a mafic lower crust and a granodioritic upper crust. The formation of stratified continental crust in general and the vertical extent of processes active in arc crustal columns leading to the differentiation of primitive, mantle-derived melts entering the lower crust are highly debated. To investigate where in the crustal column magma mixing, fractionation, assimilation and crystal growth occur and to what extent, we study the ~ 90 Ma magmatic flare-up event of the Cascades arc, a magma plumbing system from ~ 5 to 30 km depth. We focus on three intrusive complexes, emplaced at different depths during major regional shortening in an exceptionally thick crust (≥ 55 km1) but which are temporally related: the upper crustal Black Peak intrusion (1-3 kbar at 3.7 to 11 km; ~ 86.8 to 91.7 Ma2), the mid-crustal Mt. Stuart intrusion (3.5-4.0 kbar at 13 to 15 km; 90.8 and 96.3 Ma3) and the deep crustal Tenpeak intrusion (7 to 10 kbar at 25 to 37 km; 89.7 to 92.3 Ma4). These intrusive complexes are well characterized by geochronology showing that they have been constructed incrementally by multiple magma batches over their lifespans and thus allow the monitoring and comparison of geochemical parameters over time at different depths. We use a combination of whole rock major and trace element data and isotopes combined with detailed investigation of amphibole, which has been recognized to be important in the generation of calc-alkaline rocks in arcs to test the following hypotheses: (a) compositional bimodality is produced in the lower crust, whereas upper crustal levels are dominated by mixing to form intermediate compositions, or (b) differentiation occurs throughout the crustal column with different crystallizing phases and their compositions controlling the bulk chemistry. 1. Miller et al. 2009: GSA Special Paper 456, p. 125-149 2. Shea 2014: PhD thesis, Massachusetts Institute of Technology 3. Anderson et al. 2012

  10. Depth

    PubMed Central

    Koenderink, Jan J; van Doorn, Andrea J; Wagemans, Johan

    2011-01-01

    Depth is the feeling of remoteness, or separateness, that accompanies awareness in human modalities like vision and audition. In specific cases depths can be graded on an ordinal scale, or even measured quantitatively on an interval scale. In the case of pictorial vision this is complicated by the fact that human observers often appear to apply mental transformations that involve depths in distinct visual directions. This implies that a comparison of empirically determined depths between observers involves pictorial space as an integral entity, whereas comparing pictorial depths as such is meaningless. We describe the formal structure of pictorial space purely in the phenomenological domain, without taking recourse to the theories of optics which properly apply to physical space—a distinct ontological domain. We introduce a number of general ways to design and implement methods of geodesy in pictorial space, and discuss some basic problems associated with such measurements. We deal mainly with conceptual issues. PMID:23145244

  11. Depth.

    PubMed

    Koenderink, Jan J; van Doorn, Andrea J; Wagemans, Johan

    2011-01-01

    Depth is the feeling of remoteness, or separateness, that accompanies awareness in human modalities like vision and audition. In specific cases depths can be graded on an ordinal scale, or even measured quantitatively on an interval scale. In the case of pictorial vision this is complicated by the fact that human observers often appear to apply mental transformations that involve depths in distinct visual directions. This implies that a comparison of empirically determined depths between observers involves pictorial space as an integral entity, whereas comparing pictorial depths as such is meaningless. We describe the formal structure of pictorial space purely in the phenomenological domain, without taking recourse to the theories of optics which properly apply to physical space-a distinct ontological domain. We introduce a number of general ways to design and implement methods of geodesy in pictorial space, and discuss some basic problems associated with such measurements. We deal mainly with conceptual issues.

  12. Fission-track analysis of apatite and zircon defines a burial depth of 4 to 7 km for lowermost Upper Devonian, Catskill Mountains, New York

    NASA Astrophysics Data System (ADS)

    Lakatos, Stephen; Miller, Donald S.

    1983-02-01

    Apatite and zircon grains separated from a sandstone layer of earliest Late Devonian age, Catskill Mountains, have been subjected to fission-track analysis. A 125-m.y. age, obtained on the apatite grains, requires a temperature for the sediment of less than 120 °C during the past 125 m.y. At some time prior to 125 m.y. ago, temperatures were above 120 °C long enough to cause complete fading of tracks. Analysis of zircon grains resulted in a fission-track age of 320 m.y. Zircon data indicate that the temperature of the sediment layer enclosing the grains did not exceed 175 to 200 °C over a 235-rn.y. period (time between sedimentation and 125 m.y. ago). If one assumes a typical geothermal gradient of 25 °C/km, a burial depth of between 4 and 7 km is indicated for the lowermost Upper Devonian, atskill Mountains. *Present address: Rensselaer Polytechnic Institute, Troy, New York 12181

  13. MgSiO3-FeSiO3-Al2O3 in the Earth's lower mantle: Perovskite and garnet at 1200 km depth

    NASA Technical Reports Server (NTRS)

    O'Neill, Bridget; Jeanloz, Raymond

    1994-01-01

    Natural pyroxene and garnet starting material are used to study the effects of joint Fe and Al substitution into MgSiO3 perovskite at approxmiately 50 GPa. Garnet is found to coexist with perovskite in samples containing both Fe and Al to pressures occurring deep into the lower mantel (approximately 1200 km depth). The volume of the perovskite unit cell is V(sub o(Angstrom(exp 3)) = 162.59 + 5.95x(sub FeSiO3) + 10.80x(sub Al2O3) with aluminum causing a significant increase in the distortion from the ideal cubic cell. On the basis of a proposed extension of the MgSiO3-Al2O3 high-pressure phase diagram toward FeSiO3, Fe is shown to partition preferentially into the garnet phase. The stability of garnet deep into the lower mantel may hinder the penetration of subducted slabs below the transition zone.

  14. Slow strain steps observed by two Ishii strainmeters within an M3 source area at a 2.9km depth, Mponeng gold mine, South Africa

    NASA Astrophysics Data System (ADS)

    Yasutake, G.; Ogawasara, H.; Kawakata, H.; Morishita, K.; Yamamoto, A.; Takeuchi, J.; Shimoda, N.; Naoi, M.; Nakatani, M.; Kato, A.; Ishii, H.; Nakao, S.; Otsuki, K.; Yamauchi, T.; Iio, Y.; Carlsten, R.; McGill, R.; Tony, T.; Aswegen, G. V.; Mendecki, A. J.; Lenegan, P.; Reserch Group Seesa

    2007-12-01

    The Research Group for Semi-controlled Earthquake-generation Experiments in South African gold mines (SeeSA) has attempted to observe the details of the source fault behavior near the Mw2-3 earthquake source area [e.g., Iio and Fukao, 1992]. At a depth of 2.9km in Mponeng gold mine, one of our observational sites, two Ishii strainmeters were installed near the fault where M3 earthquakes were anticipated [e.g., Ogasawara et al., 2005]. We analyzed the ~8-month strainmeter recordings. During this period, a high seismicity was induced by active mining, more than 5000 earthquakes (-3

  15. Seismic belt in the upper plane of the double seismic zone extending in the along-arc direction at depths of 70-100km beneath NE Japan, and its relation with the dehydration embrittlement hypothesis

    NASA Astrophysics Data System (ADS)

    Kita, S.; Okada, T.; Nakajima, J.; Matsuzawa, T.; Hasegawa, A.

    2006-12-01

    1. Introduction Dehydration embrittlement or CO2¨Cbearing devolatization embrittlement hypothesis has been proposed as a possible cause of intraslab earthquakes in several studies [e.g., Peacock, 2001; Kirby et al., 1996; Meade and Jeanloz, 1991]. Precise location of intraslab seismicity is needed to discuss its cause in these studies. Recently, a very dense nationwide seismic network (Hi-net) has been constructed by NIED in Japan. In this study, we relocate microearthquakes more precisely by using data obtained by this dense seismic network to detect the characteristic distribution of the seismicity within the Pacific slab beneath Hokkaido and Tohoku, NE Japan. 2. Data and method In the present study, we relocated events at depths of 20¨C300 km for the period from January 2002 to August 2005 from the JMA earthquake catalog. Hypocenter locations and arrival time data in the JMA catalog were used as the initial hypocenters and data for relocations. We applied the double-difference hypocenter location method (DDLM) by Waldhauser and Ellsworth (2000) to the arrival time data of the events. We also checked spatial distribution of the focal mechanisms of the events in the seismic belts and the surrounding upper seismic plane. We used focal mechanism solutions determined by Igarashi et al. (2001). 3. Results and discussion 1) There exist earthquakes occurring in the area between the upper and lower seismic planes (interplane earthquakes), and their focal mechanisms tend to be the down-dip compressional (DC-) type like those of upper plane events. 2) We found a seismic "belt" which is parallel to the iso-depth contour of the plate interface beneath the forearc area at depths of 80¨C100 km. The location of the seismic belt seems to correspond to one phase boundary (from jadeite lawsonite blueschist (H2O content: 5.4 wt% ) to lawsonite amphibole eclogite (3.0wt %) (Hacker et al., 2003)) with dehydration reaction. 3) The location of the deeper limit of seismicity of the

  16. Imaging Resolution of 410-km and 660-km Discontinuities

    NASA Astrophysics Data System (ADS)

    Deng, Kai; Zhou, Ying

    2014-05-01

    Seismic discontinuities in the mantle transition zone at depths of about 410 and 660 km are associated with olivine phase transformations. The depths of the discontinuities provide important constraints on the thermal structure of the mid mantle. Teleseismic receiver functions as well as PP and SS precursors have been widely used in imaging topographic variations of the 410 and 660 discontinuities. Ray-theory based migration and stacking methods are often used to enhance signals of the converted and reflected waves, assuming that the effects of 3-D structure in wavespeed can be averaged out. In this study, we investigate the resolution of traditional methods in imaging the 410-km and 660-km discontinuity topography based on wave propagation simulations using the Spectral Element Method (SEM). We calculate synthetic seismograms in laterally heterogeneous wavespeed models with lateral variations in the 410-km and 660-km discontinuity depths. The SEM synthetics are processed following standard migration and stacking techniques to image the discontinuities. We show that 3-D wave speed structure beneath seismic stations can introduce significant artifacts in transition zone discontinuity topography. We also investigate finite-frequency effects of P-to-S converted waves as well as PP and SS precursors in imaging the discontinuities by varying the length scale of depth variations in the 410-km and 660-km discontinuities in SEM simulations, and show that wave front healing effects depend on the length scale of the depth variation as well as epicentral distances. Finally we compare receiver function delay times with calculations based on finite frequency sensitivity and show that wave front healing effects can be properly accounted for.

  17. Rock Properties and Internal Structure of the San Andreas Fault near ~ 3 km Depth in the SAFOD Borehole Based on Meso- to Micro-scale Analyses of Phase III whole rock core

    NASA Astrophysics Data System (ADS)

    Bradbury, K.; Evans, J. P.

    2010-12-01

    We examine the relationships between rock properties and structure within ~ 41 m of PHASE III whole-rock core collected from ~ 3 km depth along the SAF in the San Andreas Fault Observatory at Depth (SAFOD) borehole, near Parkfield, CA. Direct mesoscale observations of the core are integrated with detailed petrography and microstructural analyses coupled with X-Ray Diffraction and X-Ray Fluorescence techniques to document variations in composition, alteration, and structures that may be related to deformation and/or fluid-rock interactions. Across the low velocity zone (LVZ) defined by borehole geophysical data, lithologies are comprised of a heterogeneous sequence of fine-grained sandstones, siltstones, mudstones, and shales with block-in-matrix textures and pervasively foliated fabrics. More competent clasts within the block-in-matrix materials exhibit pinch-and-swell shaped structures with crosscutting veins that do not extend into the surrounding phyllosilicate-rich matrix. Narrow fault strands at 3192 and 3302 m bound the LVZ and correspond to sites of active casing deformation (aseismic creep). Here, the rock consists of ~ 2 m thick serpentinite-bearing phyllosilicate gouge with a pervasive penetrative scaly clay fabric and phacoidal-shaped clasts. Bounding these two active slip surfaces are highly sheared and comminuted ultrafine-grained black fault rocks with abundant calcite veins parallel and oblique to the foliation trend. Localized shear surfaces bound multi-layered zones of medium to ultra-fine grained cataclasite in the near-fault environment and record multiple generations of brittle deformation processes. Deformation at high-strain rates is suggested by the presence of crack-seal veins in clasts within the block-in-matrix materials, the presence of porphyroclasts, and the development of S-C fabrics in the phyllosilicate-rich gouge. Across the fault(s) and related damage zones, foliated fabrics alternating with discrete fractures suggest a mixed

  18. Imaging Resolution of the 410-km and 660-km Discontinuities

    NASA Astrophysics Data System (ADS)

    Deng, K.; Zhou, Y.

    2014-12-01

    Structure of seismic discontinuities at depths of about 410 km and 660 km provides important constraints on mantle convection as the associated phase transformations in the transition zone are sensitive to thermal perturbations. Teleseismic P-to-S receiver functions have been widely used to map the depths of the two discontinuities. In this study, we investigate the resolution of receiver functions in imaging topographic variations of the 410-km and 660-km discontinuities based on wave propagation simulations using the Spectral Element Method (SEM). We investigate finite-frequency effects of direct P waves as well as P-to-S converted waves by varying the length scale of discontinuity topography in the transition zone. We show that wavefront healing effects are significant in broadband receiver functions. For example, at a period of 10 to 20 seconds, the arrival anomaly in P-to-S converted waves is about 50% of what predicted by ray theory when the topography length scale is in the order of 400 km. The observed arrival anomaly further reduces to 10-20% when the topography length scale reduces to about 200 km. We calculate 2-D boundary sensitivity kernels for direct P waves as well as receiver functions based on surface wave mode summation and confirm that finite frequency-effects can be properly accounted for. Three-dimensional wavespeed structure beneath seismic stations can also introduce significant artifacts in transition zone discontinuity topography if time corrections are not applied, and, the effects are dependent on frequency.

  19. Long-term, on-site borehole monitoring of gases released from an “active” fault system at 3.6km depth, TauTona Gold Mine, South Africa

    NASA Astrophysics Data System (ADS)

    Lippmann-Pipke, J.; Erzinger, J.; Zimmer, M.; Kujawa, C.; Boettcher, M. S.; Moller, H.; van Heerden, E.; Bester, A.; Reches, Z.

    2009-12-01

    Fluid transport and seismicity are interrelated. Fluids can trigger earthquakes and seismic activity can release fluids from rock formations. The study of this relationship requires direct and near-field observations at focal depth. The international DAFSAM-NELSAM*-projects focus on building the earthquake laboratory in deep gold mines in South Africa. Our DAFGAS-project (Drilling Active Faults - Gas Analytical System) aims to quantify the gases released during seismic events. One motivation for the project is to investigate the hypothesis that released fluids might be a nutrient supply for microbial ecosystems in active fault zones. Extensive underground activities started in 2004 with establishing a 25m2 cubby within the Pretorius fault zone at 3.6 km depth for the save installation of comprehensive technical equipment. For DAFGAS, subsequently two different gas analytical units were installed to measure gases collected in a 40 m long borehole crossing the fault. The DAFGAS Team and our collaborators overcame numerous technical problems. Since 2007 a dedicated air-conditioned box protects a mass spectrometer, pumps, a PC, a radon detector and electronics from the harsh underground environment. Since 2009 gas sensitive sensors and a data logger replace the spectrometer and the PC. In parallel the NELSAM project has installed 9 seismometers in a narrow network surrounding the gas collection system. The accelerometers and geophones record mining activities (e.g. drilling and ore-production blasts) as well as tens of mining-induced earthquakes (magnitude ≥ -4) on and around the Pretorius Fault each day. Data from three years is presented: Borehole temperature at 40m increased by about 0.8 °C/year to 52.3 °C; different scales of pressure variations on surface (869±5) mbar (three-week mean, maximal and minimal daily mean) and below surface (1130±15) mbar are explained by the barometric formula. The major gas concentrations are constant and air-like with 78 % N2

  20. Coexistence of "wet-" and "dry-clinopyroxenes" in garnet-clinopyroxene rock from the Kokchetav Massif - Evidence for local heterogeneity of H2O activity at the depth > 200 km

    NASA Astrophysics Data System (ADS)

    Sakamaki, K.; Ogasawara, Y.

    2012-12-01

    reintegrated K2O from the guest and the host), respectively. These compositions suggest Cpx formations under UHP both in high-H2O and low-H2O activity conditions The co-existence of wet-Cpx and dry-Cpx suggests the local heterogeneity of H2O activity in a thin section scale. H2O played an important role for the formation of this metasomatic rock induced by H2O infiltration under UHP. Clinopyroxene was a main water reservoir in this rock under UHP and a good recorder for the intensity and the heterogeneity of H2O activity during UHP metamorphism. Sakamaki et al. (2011) reported abundant OH in titanite of this rock, and they concluded that this rock was metamorphosed at H2O-rich environment at the depth > 200 km; however, present study indicates that some domains of this rock were still kept dry during the infiltration of aqueous fluid. The role of aqueous fluid during UHP metamorphism and the local heterogeneity of aqueous fluid infiltration in subducted material will be a key aspect. These features can be explained by "Intraslab UHP metasomatism" model (Ogasawara, 2009). References: Sakamaki, K., Morozumi, H. & Ogasawara, Y. (2011), AGU Abstracts, V23E-2600. Ogasawara, Y. (2009). Waseda University Press.

  1. 1 CFR 5.10 - Forms of publication.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Forms of publication. 5.10 Section 5.10 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.10 Forms of publication. Pursuant to section 1506 of title 44, United States Code, the Administrative Committee...

  2. 1 CFR 5.10 - Forms of publication.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Forms of publication. 5.10 Section 5.10 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.10 Forms of publication. Pursuant to section 1506 of title 44, United States Code, the Administrative Committee...

  3. 1 CFR 5.10 - Forms of publication.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Forms of publication. 5.10 Section 5.10 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.10 Forms of publication. Pursuant to section 1506 of title 44, United States Code, the Administrative Committee...

  4. 34 CFR 5.10 - Public reading room.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Public reading room. 5.10 Section 5.10 Education Office... Available to the Public § 5.10 Public reading room. (a) General. Pursuant to 5 U.S.C. 552(a)(2), the Department maintains a public reading room containing agency records that the FOIA requires to be...

  5. 34 CFR 5.10 - Public reading room.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Public reading room. 5.10 Section 5.10 Education Office... Available to the Public § 5.10 Public reading room. (a) General. Pursuant to 5 U.S.C. 552(a)(2), the Department maintains a public reading room containing agency records that the FOIA requires to be...

  6. 34 CFR 5.10 - Public reading room.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Public reading room. 5.10 Section 5.10 Education Office... Available to the Public § 5.10 Public reading room. (a) General. Pursuant to 5 U.S.C. 552(a)(2), the Department maintains a public reading room containing agency records that the FOIA requires to be...

  7. 34 CFR 5.10 - Public reading room.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Public reading room. 5.10 Section 5.10 Education Office... Available to the Public § 5.10 Public reading room. (a) General. Pursuant to 5 U.S.C. 552(a)(2), the Department maintains a public reading room containing agency records that the FOIA requires to be...

  8. 36 CFR 5.10 - Eating, drinking, or lodging establishments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Eating, drinking, or lodging establishments. 5.10 Section 5.10 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.10 Eating, drinking, or lodging establishments. (a)...

  9. 36 CFR 5.10 - Eating, drinking, or lodging establishments.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Eating, drinking, or lodging establishments. 5.10 Section 5.10 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.10 Eating, drinking, or lodging establishments. (a)...

  10. 6 CFR 5.10 - Preservation of records.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 6 Domestic Security 1 2010-01-01 2010-01-01 false Preservation of records. 5.10 Section 5.10 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY DISCLOSURE OF RECORDS AND INFORMATION Freedom of Information Act § 5.10 Preservation of records. Each component shall preserve...

  11. 1 CFR 5.10 - Forms of publication.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Forms of publication. 5.10 Section 5.10 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.10 Forms of publication. Pursuant to section 1506 of title 44, United States Code, the Administrative Committee...

  12. 1 CFR 5.10 - Forms of publication.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Forms of publication. 5.10 Section 5.10 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.10 Forms of publication. Pursuant to section 1506 of title 44, United States Code, the Administrative Committee...

  13. 36 CFR 5.10 - Eating, drinking, or lodging establishments.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., Rocky Mountain, Sequoia-Kings Canyon, Yellowstone, and Yosemite National Parks may be operated without a... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Eating, drinking, or lodging establishments. 5.10 Section 5.10 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF...

  14. 30 CFR 5.10 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MINING PRODUCTS FEES FOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS § 5.10 Purpose and scope... proportionate share of management, administration and operation of the Approval and Certification Center...

  15. Origins of the 520-km discontinuity

    NASA Astrophysics Data System (ADS)

    Vinnik, Lev

    2016-04-01

    The 520-km discontinuity is often explained by the phase transition from wadsleyite to ringwoodite, although the theoretical impedance of this transition is so small that the related converted and reflected seismic phases could hardly be seen in the seismograms. At the same time there are numerous reports on observations of a large discontinuity at this depth, especially in the data on SS precursors and P-wave wide-angle reflections. Revenaugh and Jordan (1991) argued that this discontinuity is related to the garnet/post-garnet transformation. Gu et al. (1998) preferred very deep continental roots extending into the transition zone. Deuss and Woodhouse proposed splitting of the 520-km discontinuity into two discontinuities, whilst Bock (1994) denied evidence of the 520-km discontinuity in the SS precursors. Our approach to this problem is based on the analysis of S and P receiver functions. Most of our data are related to hot-spots in and around the Atlantic where the appropriate converted phases are often comparable in amplitude with P410s and S410p. Both S and P receiver functions provide strong evidence of a low S velocity in a depth range from 450 km to 510 km at some locations. The 520-km discontinuity appears to be the base of this low-velocity layer. Our observations of the low S velocity in the upper transition zone are very consistent with the indications of a drop in the solidus temperature of carbonated peridotite in the same pressure range (Keshav et al. 2011), and this phenomenon provides a viable alternative to the other explanations of the 520-km discontinuity.

  16. 30 CFR 5.10 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS FEES FOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS § 5.10 Purpose and scope... (investigators), including administrative review of applications, analysis of drawings, technical...

  17. 30 CFR 5.10 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS FEES FOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS § 5.10 Purpose and scope... (investigators), including administrative review of applications, analysis of drawings, technical...

  18. 36 CFR 5.10 - Eating, drinking, or lodging establishments.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Eating, drinking, or lodging... INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.10 Eating, drinking, or lodging establishments. (a) No establishment offering food, drink, or lodging for sale on any privately owned lands under the...

  19. 36 CFR 5.10 - Eating, drinking, or lodging establishments.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Eating, drinking, or lodging... INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.10 Eating, drinking, or lodging establishments. (a) No establishment offering food, drink, or lodging for sale on any privately owned lands under the...

  20. Selenographic distribution of apparent crater depth

    NASA Astrophysics Data System (ADS)

    de Hon, R. A.

    If apparent crater depth is a function of crater diameter, then the frequencies of crater depth and diameter should be similar and the distribution of apparent depths of craters on the lunar surface should be random. Apparent depths of complex craters, which range from 0.2 to 4.3 km on the moon, exhibit little correlation with crater diameters. Crater frequency decreases at increasing diameters, but apparent crater depth displays a Gaussian distribution. The average crater depth for all young craters is 1.8 km. The mean depth of craters on the maria is 1.3 km, and the mean depth of craters on the highlands is 2.1 km. A contour map of apparent crater depths exhibits sufficient organization to suggest that the apparent crater depth is correlated to major lunar provinces. In general, regions of shallow craters are associated with basin interiors. Greater apparent depths are associated with highland terrains.

  1. Temperature Structure of the 80 Km to 120 Km Region

    NASA Technical Reports Server (NTRS)

    Forbes, J. M.

    1985-01-01

    Between 80 and 120 km the CIRA 1972 model is based heavily on NASA Meteorological Sounding Rocket Program (MSRP) data collected prior to 1967. Since about 1970 an abundance of E-region (100-130 km) temperature data from the incoherent scatter facilities at Arecibo, Millstone Hill, and St. Santin have also become available. The present study examines the temperature structure of the 80 to 120 km region given considerable additional MSRP rocket data, thus providing better seasonal, latitudinal, and longitudinal coverage in the 80 to 100 km region, and a combination of incoherent scatter and rocket data in the 100 to 120 km region which allows a much improved delineation of lower thermosphere temperature structue. Although some individual station comparisons indicate measurable asymmetries in longitude and latitude, data are still insufficient to separate these effects. Specific recommendations of the new CIRA are given.

  2. KM Education in LIS Programs

    ERIC Educational Resources Information Center

    Rehman, Sajjad ur; Chaudhry, Abdus Sattar

    2005-01-01

    This paper investigates the perceptions of the heads of 12 Library and Information Science (LIS) schools on Knowledge Management (KM) education. These heads from North America, Europe and the Pacific region had either been offering KM courses or had an apparent interest in such programs. Data about perceptions were gathered on the nature of their…

  3. KM3NeT

    SciTech Connect

    Jong, M. de; Collaboration: KM3NeT Collaboration

    2015-07-15

    KM3NeT is a large research infrastructure, that will consist of a network of deep-sea neutrino telescopes in the Mediterranean Sea. The main objective of KM3NeT is the discovery and subsequent observation of high-energy neutrino sources in the Universe. A further physics perspective is the measurement of the mass hierarchy of neutrinos. A corresponding study, ORCA, is ongoing within KM3NeT. A cost effective technology for (very) large water Cherenkov detectors has been developed based on a new generation of low price 3-inch photo-multiplier tubes. Following the successful deployment and operation of two prototypes, the construction of the KM3NeT research infrastructure has started. The prospects of the different phases of the implementation of KM3NeT are summarised.

  4. KM3NeT

    NASA Astrophysics Data System (ADS)

    de Jong, M.

    2015-07-01

    KM3NeT is a large research infrastructure, that will consist of a network of deep-sea neutrino telescopes in the Mediterranean Sea. The main objective of KM3NeT is the discovery and subsequent observation of high-energy neutrino sources in the Universe. A further physics perspective is the measurement of the mass hierarchy of neutrinos. A corresponding study, ORCA, is ongoing within KM3NeT. A cost effective technology for (very) large water Cherenkov detectors has been developed based on a new generation of low price 3-inch photo-multiplier tubes. Following the successful deployment and operation of two prototypes, the construction of the KM3NeT research infrastructure has started. The prospects of the different phases of the implementation of KM3NeT are summarised.

  5. The Hydrothermal Vent Biosampler (HVB) Developed to Collect `Pristine' Samples (<6.5km depth, 400C, 0.2u pore) for Microbial Analyses. It's use in Eyjafjordur Fjord, Iceland & Myojin Knoll & Planned deployment on the Myojin Knoll & Suiyo Seamount.

    NASA Astrophysics Data System (ADS)

    Behar, A.; Bruckner, J.; Venkateswaran, K.; Matthews, J.

    2006-12-01

    Marine hydrothermal systems and the unique biota associated with them represent some of the most interesting ecosystems on the planet. These `extreme' environments are often composed of vents spewing super-heated fluid containing a variety of minerals and reduced compounds, numerous of which can be used as substrates for growth by microorganisms. To accurately describe the diversity and distribution of these chemosynthetic communities, it is essential to collect samples from defined locations associated with a given hydrothermal vent without contamination from the surrounding water column (e.g. the collected samples are `pristine'). Additionally, samples need to be collected in sufficient volume to a) account for the potential low biomass of these environments and b) provide modern molecular techniques with adequate sample material. The hydrothermal vent biosampler (HVB) was developed to collect `pristine' hydrothermal vent samples for microbial analyses. Utilizing an array of sensors (temperature monitors and flow meters), the system can relay real time data regarding sampling conditions allowing accurate placement of the HVB's collection nozzle and ensuring samples are collected from defined locations. The unit has been designed to withstand extreme conditions (source water temperatures >400°C) and has been pressure tested to a simulated depth of 6.5km and undergone field trials along the Eyjafjordur Fjord hydrothermal system (Iceland). Collection of sufficient biomass is achieved through employment of a series of filters (90, 60, 7 and 0.2 ìm pore sizes) that concentrate ~20L of hydrothermal fluid to a final volume of 500-ml. Filtered samples can be directly collected from the HVB for subsequent biological analyses (both culture- and molecular-based). In conjunction with JAMSTEC, further field exercises along the Myojin Knoll and Suiyo Seamount have been planned for November 2006.

  6. BROWN DWARF DISKS AT AGES OF 5-10 Myr

    SciTech Connect

    Riaz, Basmah; Lodieu, Nicolas; Gizis, John E.

    2009-11-01

    We present Spitzer/IRAC and MIPS 24 mum observations for 28 brown dwarfs in the Upper Scorpius (UppSco) region. We find a disk fraction of 10.7%{sup +8.7%} {sub -3.3%}. One object shows a small excess at 24 mum but none at shorter wavelengths, and may be a candidate transition disk. Three objects show emission in the 10 mum silicate feature and we present compositional fits for these sources. Flat structures are observed for all disk sources in UppSco. Also presented are the MIPS/70 mum observations for the TW Hydrae Association brown dwarf 2MASS J1139511-315921. We discuss the structure and chemistry of brown dwarf disks at ages of approx5-10 Myr, and consider the possible effects of the brown dwarf densities in these clusters on the disk lifetimes.

  7. Inference of mantle viscosity for depth resolutions of GIA observations

    NASA Astrophysics Data System (ADS)

    Nakada, Masao; Okuno, Jun'ichi

    2016-11-01

    Inference of the mantle viscosity from observations for glacial isostatic adjustment (GIA) process has usually been conducted through the analyses based on the simple three-layer viscosity model characterized by lithospheric thickness, upper- and lower-mantle viscosities. Here, we examine the viscosity structures for the simple three-layer viscosity model and also for the two-layer lower-mantle viscosity model defined by viscosities of η670,D (670-D km depth) and ηD,2891 (D-2891 km depth) with D-values of 1191, 1691 and 2191 km. The upper-mantle rheological parameters for the two-layer lower-mantle viscosity model are the same as those for the simple three-layer one. For the simple three-layer viscosity model, rate of change of degree-two zonal harmonics of geopotential due to GIA process (GIA-induced J˙2) of -(6.0-6.5) × 10-11 yr-1 provides two permissible viscosity solutions for the lower mantle, (7-20) × 1021 and (5-9) × 1022 Pa s, and the analyses with observational constraints of the J˙2 and Last Glacial Maximum (LGM) sea levels at Barbados and Bonaparte Gulf indicate (5-9) × 1022 Pa s for the lower mantle. However, the analyses for the J˙2 based on the two-layer lower-mantle viscosity model only require a viscosity layer higher than (5-10) × 1021 Pa s for a depth above the core-mantle boundary (CMB), in which the value of (5-10) × 1021 Pa s corresponds to the solution of (7-20) × 1021 Pa s for the simple three-layer one. Moreover, the analyses with the J˙2 and LGM sea level constraints for the two-layer lower-mantle viscosity model indicate two viscosity solutions: η670,1191 > 3 × 1021 and η1191,2891 ˜ (5-10) × 1022 Pa s, and η670,1691 > 1022 and η1691,2891 ˜ (5-10) × 1022 Pa s. The inferred upper-mantle viscosity for such solutions is (1-4) × 1020 Pa s similar to the estimate for the simple three-layer viscosity model. That is, these analyses require a high viscosity layer of (5-10) × 1022 Pa s at least in the deep mantle, and suggest

  8. Apparent Depth.

    ERIC Educational Resources Information Center

    Nassar, Antonio B.

    1994-01-01

    Discusses a well-known optical refraction problem where the depth of an object in a liquid is determined. Proposes that many texts incorrectly solve the problem. Provides theory, equations, and diagrams. (MVL)

  9. β-Nitro-5,10,15-tritolylcorroles

    PubMed Central

    Stefanelli, Manuela; Pomarico, Giuseppe; Tortora, Luca; Nardis, Sara; Fronczek, Frank R.; McCandless, Gregory T.; Smith, Kevin M.; Manowong, Machima; Chen, Ping; Kadish, Karl M.; Rosa, Angela; Ricciardi, Giampaolo; Paolesse, Roberto

    2012-01-01

    Functionalization of the β-pyrrolic positions of the corrole macrocycle with –NO2 groups is limited at present to metallocorrolates due to of the instability exhibited by corrole free bases under oxidizing conditions. A careful choice of the oxidant can limit the transformation of corroles into decomposition products or isocorrole species, preserving the corrole aromaticity, and thus allowing the insertion of nitro groups onto the corrole framework. Here we report results obtained by reacting 5,10,15-tritolylcorrole (TTCorrH3) with the AgNO2/NaNO2 system, to give mono- and di-nitrocorrole derivatives when stoichiometry is carefully controlled. Reactions were found to be regioselective, affording the 3-NO2TTCorrH3 and 3,17-(NO2)2TTCorrH3 isomers as the main products in the case of mono- and di-substitution, in 53 and 20% yields, respectively. In both cases, traces of other mono- and di-substituted isomers were detected, which were structurally characterized by X-ray crystallography. The influence of the β-nitro substituents on the corrole properties is studied in detail by UV-visible, electrochemical, and spectroelectrochemical characterization of these functionalized corroles. Density Functional Theory (DFT) and time-dependent DFT (TDDFT) calculations of the ground and excited state properties of these β-nitrocorrole derivatives also afforded significant information, closely matching the experimental observations. It is found that the β-NO2 substituents conjugate with the π-aromatic system of the macrocycle, which initiates significant changes in both the spectroscopic and redox properties of the so functionalized corroles. This effect is more pronounced when the nitro group is introduced at the 2-position, because in this case the conjugation is, for steric reasons, more efficient than in the 3-nitro isomer. PMID:22668242

  10. Purification and characterization of NADP(+)-dependent 5,10-methylenetetrahydrofolate dehydrogenase from Peptostreptococcus productus marburg.

    PubMed Central

    Wohlfarth, G; Geerligs, G; Diekert, G

    1991-01-01

    The 5,10-methylenetetrahydrofolate dehydrogenase of heterotrophically grown Peptostreptococcus productus Marburg was purified to apparent homogeneity. The purified enzyme catalyzed the reversible oxidation of methylenetetrahydrofolate with NADP+ as the electron acceptor at a specific activity of 627 U/mg of protein. The Km values for methylenetetrahydrofolate and for NADP+ were 27 and 113 microM, respectively. The enzyme, which lacked 5,10-methenyltetrahydrofolate cyclohydrolase activity, was insensitive to oxygen and was thermolabile at temperatures above 40 degrees C. The apparent molecular mass of the enzyme was estimated by gel filtration to be 66 kDa. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of a single subunit of 34 kDa, accounting for a dimeric alpha 2 structure of the enzyme. Kinetic studies on the initial reaction velocities with different concentrations of both substrates in the absence and presence of NADPH as the reaction product were interpreted to indicate that the enzyme followed a sequential reaction mechanism. After gentle ultracentrifugation of crude extracts, the enzyme was recovered to greater than 95% in the soluble (supernatant) fraction. Sodium (10 microM to 10 mM) had no effect on enzymatic activity. The data were taken to indicate that the enzyme was similar to the methylenetetrahydrofolate dehydrogenases of other homoacetogenic bacteria and that the enzyme is not involved in energy conservation of P. productus. PMID:1899860

  11. Km3Net Italy - Seafloor network

    NASA Astrophysics Data System (ADS)

    Papaleo, Riccardo

    2016-04-01

    The KM3NeT European project aims to construct a large volume underwater neutrino telescope in the depths of the Mediterranean Sea. INFN and KM3NeT collaboration, thanks to a dedicated funding of 21.000.000 € (PON 2007-2013), are committed to build and deploy the Phase 1 of the telescope, composed of a network of detection units: 8 towers, equipped with single photomultiplier optical modules, and 24 strings, equipped with multi-photomultipliers optical modules. All the towers and strings are connected to the main electro optical cable by means of a network of junction boxes and electro optical interlink cables. Each junction box is an active node able to provide all the necessary power to the detection units and to guarantee the data transmission between the detector and the on-shore control station. The KM3NeT Italia project foresees the realization and the installation of the first part of the deep sea network, composed of three junction boxes, one for the towers and two for the strings. In July 2015, two junction boxes have been deployed and connected to the new cable termination frame installed during the same sea campaign. The third and last one will be installed in November 2015. The status of the deep sea network is presented together with technical details of the project.

  12. MODIS 3km Aerosol Product: Algorithm and Global Perspective

    NASA Technical Reports Server (NTRS)

    Remer, L. A.; Mattoo, S.; Levy, R. C.; Munchak, L.

    2013-01-01

    After more than a decade of producing a nominal 10 km aerosol product based on the dark target method, the MODIS aerosol team will be releasing a nominal 3 km product as part of their Collection 6 release. The new product differs from the original 10 km product only in the manner in which reflectance pixels are ingested, organized and selected by the aerosol algorithm. Overall, the 3 km product closely mirrors the 10 km product. However, the finer resolution product is able to retrieve over ocean closer to islands and coastlines, and is better able to resolve fine aerosol features such as smoke plumes over both ocean and land. In some situations, it provides retrievals over entire regions that the 10 km product barely samples. In situations traditionally difficult for the dark target algorithm, such as over bright or urban surfaces the 3 km product introduces isolated spikes of artificially high aerosol optical depth (AOD) that the 10 km algorithm avoids. Over land, globally, the 3 km product appears to be 0.01 to 0.02 higher than the 10 km product, while over ocean, the 3 km algorithm is retrieving a proportionally greater number of very low aerosol loading situations. Based on collocations with ground-based observations for only six months, expected errors associated with the 3 km land product are determined to be greater than for the 10 km product: 0.05 0.25 AOD. Over ocean, the suggestion is for expected errors to be the same as the 10 km product: 0.03 0.05 AOD. The advantage of the product is on the local scale, which will require continued evaluation not addressed here. Nevertheless, the new 3 km product is expected to provide important information complementary to existing satellite-derived products and become an important tool for the aerosol community.

  13. Substrate specificity of mammalian folylpolyglutamate synthetase for 5,10-dideazatetrahydrofolate analogs.

    PubMed

    Habeck, L L; Mendelsohn, L G; Shih, C; Taylor, E C; Colman, P D; Gossett, L S; Leitner, T A; Schultz, R M; Andis, S L; Moran, R G

    1995-08-01

    The metabolism of 5,10-dideazatetrahydrofolate (DDATHF [lometrexol]) to polyglutamate derivatives by folylpoly-gamma-glutamate synthetase (FPGS) plays a central role in the activity of this compound as an antineoplastic agent. The availability of a series of DDATHF derivatives differing in structure throughout the molecule has allowed a study of the structural requirements for substrate activity with mouse liver and hog liver FPGS. Kinetics of the polyglutamation reaction in vitro have been related to the potency of these compounds as inhibitors of the growth of human CEM leukemic cells. The structure-activity relationships for enzyme from both sources were nearly identical. FPGS from both species showed a broad acceptance for structural changes in the pyridopyrimidine ring, in the phenyl group, and in the intermediate bridge region, with structural changes in these regions being reflected in changes in Km for FPGS but much more modest alterations in Vmax. The data suggested that the phenyl ring was not contributing to any pi-pi hydrophobic interactions. It appeared to function primarily in maintaining a favorable distance between the pyridopyrimidine ring and the glutamate side chain. The lowest Km values were found for DDATHF analogs in which there were small alterations at the 10 position, e.g., 5-deazatetrahydrofolate, 10-methyl-DDATHF, and 10-formyl-5-deazatetrahydrofolate; the first-order rate constants for these substrates were the highest in this series, an indication of the efficiency of polyglutamation at low substrate concentrations. After correction for the intrinsic inhibitory activity of the parent DDATHF analog as an inhibitor of the target enzyme, the first-order rate constants for FPGS were found to be predictive of the potency of tumor cell growth inhibition for most of the compounds in this structural series.

  14. 43 CFR 5.10 - Can I appeal a decision not to issue a permit?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Can I appeal a decision not to issue a permit? 5.10 Section 5.10 Public Lands: Interior Office of the Secretary of the Interior COMMERCIAL FILMING AND SIMILAR PROJECTS AND STILL PHOTOGRAPHY ON CERTAIN AREAS UNDER DEPARTMENT JURISDICTION...

  15. 43 CFR 5.10 - Can I appeal a decision not to issue a permit?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Can I appeal a decision not to issue a permit? 5.10 Section 5.10 Public Lands: Interior Office of the Secretary of the Interior COMMERCIAL FILMING AND SIMILAR PROJECTS AND STILL PHOTOGRAPHY ON CERTAIN AREAS UNDER DEPARTMENT JURISDICTION...

  16. 41 CFR 102-5.10 - What does this part cover?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What does this part cover? 102-5.10 Section 102-5.10 Public Contracts and Property Management Federal Property Management... transport employees between their homes and places of work....

  17. 17 CFR 5.10 - Risk assessment recordkeeping requirements for retail foreign exchange dealers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... requirements for retail foreign exchange dealers. 5.10 Section 5.10 Commodity and Securities Exchanges... recordkeeping requirements for retail foreign exchange dealers. (a) Requirement to maintain and preserve information. (1) Each retail foreign exchange dealer registered with the Commission pursuant to section...

  18. Neutrophil haptotaxis induced by the lectin KM+.

    PubMed

    Ganiko, L; Martins, A R; Espreáfico, E M; Roque-Barreira, M C

    1998-05-01

    KM+ is a D-mannose binding lectin from Artocarpus integrifolia that induces neutrophil migration in vitro and in vivo. This attractant activity was shown to be caused by haptotaxis rather than chemotaxis. The inhibition by D-mannose of the neutrophil attraction exerted by KM+, both in vitro and in vivo, supports the idea that haptotaxis is triggered in vivo by the sugar binding sites interacting with glycoconjugates located on the neutrophil surface and in the extracellular matrix. In the present study an in vivo haptotaxis assay was performed by intradermally (i.d.) injecting 125I-KM+ (200 ng), which led to a selective staining of loose connective tissue and vascular endothelium. The radiolabelled area exhibited a maximum increase (five-fold) in neutrophil infiltration 3 h after injection, relative to i.d. 200 ng 125I-BSA. We characterized the ex vivo binding of KM+ to tissue elements by immunohistochemistry, using paraformaldehyde-fixed, paraffin-embedded, untreated rat skin. Bound KM+ was detected with an affinity-purified rabbit IgG anti-KM+ and visualized with an alkaline phosphatase based system. KM+ binding to connective tissue and vascular endothelium was inhibited by preincubating KM+ with 0.4 mM D-mannose and was potentiated by heparan sulfate (100 microg ml(-1)). An in vitro assay carried out in a Boyden microchamber showed that heparan sulfate potentiated the attractant effect of 10 microg KM+ by 34%. The present data suggest that KM+ induces neutrophil migration in vivo by haptotaxis and that the haptotactic gradient could be provided by the interaction of the KM+ carbohydrate recognition site(s) with mannose-containing glycoconjugate(s) in vascular endothelium and connective tissue. Heparan sulfate would act as an accessory molecule, enhancing the KM+ tissue binding and potentiating the induced neutrophil haptotaxis.

  19. Seismological detection of "730-km" discontinuity beneath Japan subduction zone

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Park, J. J.; Karato, S. I.

    2015-12-01

    Because the mantle transition zone likely contains a large amount of water (Karato, 2011; Pearson et al., 2014), vertical material transport across the transition would cause partial melting that may produce seismic signals above and/or below the transition zone. Schmandt et al. (2014) observed a seismic low-velocity zone (LVZ) at the top of the lower mantle (~730 km) beneath the southwestern US, arguing for dehydration melting due to downward flow across the 670-km discontinuity (670) from the transition zone. These authors further proposed a correlation between seismic velocity reductions and the direction of water transport, in which LVZ at ~730 km indicates materials moving downward from the transition zone, while the lack of LVZ at this depth would suggest an upward flow of mantle materials. Other regions also need to be investigated to confirm the correlation between this seismic feature and mantle water transport. We test their model by detecting "730-km" discontinuity beneath the Japan subduction zone using frequency-dependent receiver functions. In addition, water transport above the 410-km discontinuity (410) also plays an important role in global water circulation (Bercovici and Karato, 2003). Seismological studies (e.g. Courtier and Revenaugh, 2007; Schaeffer and Bostock, 2010) have observed LVZs above the 410, which might be caused by dehydration melting due to the upwelling of hydrated materials across the 410-km discontinuity from the transition zone. In this study, we also detect potential LVZs above 410 to establish a correlation between seismic velocity drop and flow direction. Around the Japan subduction zone, our preliminary results show evidence of low velocity zones below 670 in regions where stagnant slab is present for a substantial amount of time but not in other regions suggesting a variety of vertical mass transport in this region. Key words: transition zone, water transport, subduction zone, melting, receiver functions

  20. Measurements of light background at large depth in the ocean

    NASA Technical Reports Server (NTRS)

    Bannykh, A. E.; Beresnev, V. I.; Gaidash, V. A.; Gulkhandanyan, O. M.; Ivanov, V. I.; Markov, M. A.; Paka, V. T.; Shtranikh, I. V.; Surin, N. M.; Volkov, A. N.

    1985-01-01

    The mean intensity of Cerenkov emission from the products of K(40) decay and bioluminescence was measured at depths to 5 km. The intensity of ocean light background is found to depend upon depth and at the 5 km level is equal on averaged to 300 + or - 60 quanta/sq cms into spatial angle of 2 pi sterradian in transparency window. The amplitudes, duration and number of BL flashes were measured at various depths. The intensive flashes due to BL are shown to be observed rather seldom at depths over 4 km.

  1. KM3NeT-ARCA project status and plan

    NASA Astrophysics Data System (ADS)

    Coniglione, R.

    2016-04-01

    The KM3NeT Collaboration aims at building a research infrastructure in the depths of the Mediterranean Sea hosting a cubic kilometre neutrino telescope. The KM3NeT/ARCA detector is the ideal instrument to look for high-energy neutrino sources thanks to the latitude of the detector and to the optical characteristics of the sea water. The detector latitude allows for a wide coverage of the observable sky including the region of the Galactic centre and the optical sea water properties allow for the measure of the neutrino direction with excellent angular resolution also for cascade events. The technologically innovative components of the detector and the status of construction will be presented as well as the capability it offers to discover neutrinos.

  2. News from KM3NeT

    SciTech Connect

    Katz, Ulrich F.; Collaboration: KM3NeT Collaboration

    2014-11-18

    KM3NeT is a future research infrastructure in the Mediterranean Sea, hosting a multi-cubic-kilometre neutrino telescope and nodes for Earth and Sea sciences. In this report we shortly summarise the genesis of the KM3NeT project and present key elements of its technical design. The physics objectives of the KM3NeT neutrino telescope and some selected sensitivity estimates are discussed. Finally, some first results from prototype operations and the next steps towards implementation – in particular the first construction phase in 2014/15 – are described.

  3. Acoustically detected hydrocarbon plumes rising from 2-km depths in Guaymas Basin, Gulf of California

    SciTech Connect

    Merewether, R.; Olsson, M.S.; Lonsdale, P.

    1985-03-10

    Plumes extending nearly 1000 m from the 1500--2000 m deep seafloor of Guaymas Basin were detected from below the 23.5-kHz inverted echo-sounder of the Scripps Deep Two vehicle. Individual sound reflectors (bubbles or drops) rise at approximately 17 cm/s in one plume. The Deep Tow side scan records provide more information on the plumes' structure at the altitude of the vehicle (75 m), where some form multiple side scan targets, one 20 m across. Near-bottom 4-kHz profiles show that plumes overlie young fault traces associated with extensional faulting at the basin's spreading centers of outcrops of tilted beds beside strike-slip faults. We infer from analysis of the Deep Tow observations, field relationships, and knowledge of the geology of this basin that the plumes are made of light hydrocarbons, perhaps mainly methane, that emanate from seabed seeps. One of the acoustically detected plumes was at a spreading-axis hydrothermal field, which has many buoyant, acoustically transparent thermal plumes, some of which are rich in dissolved hydrocarbons.

  4. Metamorphic hydrology at 13 km depth and 400/sup 0/-550/sup 0/C

    SciTech Connect

    Ferry, J.M.

    1985-01-01

    The pattern of metamorphic fluid flow through six large outcrops of regionally metamorphosed impure carbonate rock from a single stratigraphic unit in south-central Maine was determined by quantitative measurement of the progress of the prograde devolatilization reactions. With reference to adjacent pelitic schists, the outcrops are located in the chlorite, biotite, garnet, staurolite-andalusite, and sillimanite zones. Two components of flow were detected: a pervasive component and a channelized component. In the chlorite, biotite, and garnet zones fluid flow was highly channelized along bedding with enhanced flow occurring within the more impure carbonate layers that acted as metamorphic aquifers. A smaller amount of pervasive background flow also occurred within the intervening more impure carbonate layers that acted as metamorphic aquifers. A smaller amount of pervasive background flow also occurred within the intervening more pure carbonate layers that acted as metamorphic aquitards. Fluid-rock ratios differ between aquifers and aquitards by a factor greater than 50 over distances of 1 mm or less at grades lower than the staurolite-andalusite zone. Two generalization can be made about the affect of metamorphic grade on patterns of fluid flow: with increasing grade (1) flow becomes less channelized and more pervasive and (b) the average time-integrated fluid flux for a whole outcrop increases. Patterns of metamorphic fluid flow may be rationalized in terms of a model for reaction-enhanced permeability.

  5. Status of KM3NeT

    NASA Astrophysics Data System (ADS)

    Riccobene, G.

    2016-07-01

    The recent observation of cosmic neutrinos by IceCube has pushed the quest towards the identification of cosmic sources of high-energy particles. The KM3NeT Collaboration is now ready to launch the massive construction of detection units to be installed in deep sea to build a km-cubic size neutrino telescope. The main elements of the detector, the status of the project and the expected perfomances are briefly reported.

  6. Potential of KM3NeT to observe galactic neutrino point-like sources

    NASA Astrophysics Data System (ADS)

    Trovato, Agata

    2016-07-01

    KM3NeT (http://www.km3net.org">http://www.km3net.org) will be the next-generation cubic-kilometre-scale neutrino telescope to be installed in the depths of the Mediterranean Sea. This location will allow for surveying the Galactic Centre, most of the Galactic Plane as well as a large part of the sky. We report KM3NeT discovery potential for the SNR RXJ1713.7-3946 and the PWN Vela X and its sensitivity to point-like sources with an E-2 spectrum.

  7. Focal Depth of the WenChuan Earthquake Aftershocks from modeling of Seismic Depth Phases

    NASA Astrophysics Data System (ADS)

    Luo, Y.; Zeng, X.; Chong, J.; Ni, S.; Chen, Y.

    2008-12-01

    After the 05/12/2008 great WenChuan earthquake in Sichuan Province of China, tens of thousands earthquakes occurred with hundreds of them stronger than M4. Those aftershocks provide valuable information about seismotectonics and rupture processes for the mainshock, particularly accurate spatial distribution of aftershocks is very informational for determining rupture fault planes. However focal depth can not be well resolved just with first arrivals recorded by relatively sparse network in Sichuan Province, therefore 3D seismicity distribution is difficult to obtain though horizontal location can be located with accuracy of 5km. Instead local/regional depth phases such as sPmP, sPn, sPL and teleseismic pP,sP are very sensitive to depth, and be readily modeled to determine depth with accuracy of 2km. With reference 1D velocity structure resolved from receiver functions and seismic refraction studies, local/regional depth phases such as sPmP, sPn and sPL are identified by comparing observed waveform with synthetic seismograms by generalized ray theory and reflectivity methods. For teleseismic depth phases well observed for M5.5 and stronger events, we developed an algorithm in inverting both depth and focal mechanism from P and SH waveforms. Also we employed the Cut and Paste (CAP) method developed by Zhao and Helmberger in modeling mechanism and depth with local waveforms, which constrains depth by fitting Pnl waveforms and the relative weight between surface wave and Pnl. After modeling all the depth phases for hundreds of events , we find that most of the M4 earthquakes occur between 2-18km depth, with aftershocks depth ranging 4-12km in the southern half of Longmenshan fault while aftershocks in the northern half featuring large depth range up to 18km. Therefore seismogenic zone in the northern segment is deeper as compared to the southern segment. All the aftershocks occur in upper crust, given that the Moho is deeper than 40km, or even 60km west of the

  8. Teaching for Creativity by Science Teachers in Grades 5-10

    ERIC Educational Resources Information Center

    Al-Abdali, Nasser S.; Al-Balushi, Sulaiman M.

    2016-01-01

    This classroom observation study explored how science teachers (N = 22) teach for creativity in grades 5-10 in Oman. We designed an observation form with 4 main categories that targeted the instructional practices related to teaching for creativity: questioning strategy, teacher's responses to students' ideas, classroom activities to support…

  9. The corrole and ferrocene marriage: 5,10,15-triferrocenylcorrolato Cu.

    PubMed

    Pomarico, Giuseppe; Vecchi, Andrea; Mandoj, Federica; Bortolini, Olga; Cicero, Daniel O; Galloni, Pierluca; Paolesse, Roberto

    2014-04-21

    Two synthetic routes have been defined for the preparation of a 5,10,15-triferrocenylcorrole Cu derivative. This complex has been characterized and the preliminary electrochemical investigation shows a strong interaction among the corrole and meso ferrocenyl substituents. The results obtained suggest that peculiar properties are gained by combining the eccentric characteristics of ferrocenyl substitution with the corrole macrocycle. PMID:24616907

  10. Towards a 1km resolution global flood risk model

    NASA Astrophysics Data System (ADS)

    Bates, Paul; Neal, Jeff; Sampson, Chris; Smith, Andy

    2014-05-01

    Recent advances in computationally efficient numerical algorithms and new High Performance Computing architectures now make high (1-2km) resolution global hydrodynamic models a realistic proposition. However in many areas of the world the data sets and tools necessary to undertake such modelling do not currently exist. In particular, five major problems need to be resolved: (1) the best globally available terrain data (SRTM) was generated from X-band interferometric radar data which does not penetrate vegetation canopies and which has significant problems in determining ground elevations in urban areas; (2) a global river bathymetry data set does not currently exist; (3) most river channels globally are less than the smallest currently resolvable grid scale (1km) and therefore require a sub-grid treatment; (4) a means to estimate the magnitude of the T year flood at any point along the global river network does not currently exist; and (5) a large proportion of flood losses are generated by off-floodplain surface water flows which are not well represented in current hydrodynamic modelling systems. In this paper we propose solutions to each of these five issues as part of a concerted effort to develop a 1km (or better) resolution global flood hazard model. We describe the new numerical algorithms, computer architectures and computational resources used, and demonstrate solutions to the five previously intractable problems identified above. We conduct a validation study of the modelling against satellite imagery of major flooding on the Mississippi-Missouri confluence plain in the central USA before outlining a proof-of-concept regional study for SE Asia as a step towards a global scale model. For SE Asia we simulate flood hazard for ten different flood return periods over the entire Thailand, Cambodia, Vietnam, Malaysia and Laos region at 1km resolution and show that the modelling produces coherent, consistent and sensible simulations of extent and water depth.

  11. Saqqar: A 34 km diameter impact structure in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Kenkmann, Thomas; Afifi, Abdulkader M.; Stewart, Simon A.; Poelchau, Michael H.; Cook, Douglas J.; Neville, Allen S.

    2015-11-01

    Here we present the first proof of an impact origin for the Saqqar circular structure in northwestern Saudi Arabia (Neville et al. ), with an apparent diameter of 34 km, centered at 29°35'N, 38°42'E. The structure is formed in Cambrian-Devonian siliciclastics and is unconformably overlain by undeformed Cretaceous and Paleogene sediments. The age of impact is not well constrained and lies somewhere between 410 and 70 Ma. The subsurface structure is constrained by 2-D reflection seismic profiles and six drilled wells. First-order structural features are a central uplift that rises approximately 2 km above regional datums, surrounded by a ring syncline. The crater rim is defined by circumferential normal faults. The central uplift and ring syncline correspond to a Bouguer gravity high and an annular ring-like low, respectively. The wells were drilled within the central uplift, the deepest among them exceed 2 km depth. Sandstone core samples from these wells show abundant indicators of a shock metamorphic overprint. Planar deformation features (PDFs) were measured with orientations along (0001), {101¯3}, and less frequently along {101¯1} and {101¯4}. Planar fractures (PFs) predominantly occur along (0001) and {101¯1}, and are locally associated with feather features (FFs). In addition, some shocked feldspar grains and strongly deformed mica flakes were found. The recorded shock pressure ranges between 5 and 15 GPa. The preserved level of shock and the absence of an allochthonous crater fill suggest that Saqqar was eroded by 1-2 km between the Devonian and Maastrichtian. The documentation of unequivocal shock features proves the formation of the Saqqar structure by a hypervelocity impact event.

  12. Physical Mechanisms for Earthquakes at Intermediate Depths

    NASA Astrophysics Data System (ADS)

    Green, H. W.; Green, H. W.

    2001-12-01

    Conventional brittle shear failure it is strongly inhibited by pressure because it relies on local tensile failure. In contrast, plastic flow processes are thermally activated, making them sensitive functions of temperature, but their pressure dependence is only moderate. As a consequence, in Earth, faulting by unassisted brittle failure is probably restricted to depths less than ~ 30 km because the rocks flow at lower stresses than they fracture. To enable faulting at greater depths, mineral reactions must occur that generate a fluid or fluid-like solid that is much weaker than the parent assemblage. Although a variety of plastic instabilities have been and continue to be proposed to explain earthquakes at depth, dehydration embrittlement remains the only experimentally verified faulting mechanism consistent with the pressures and compositions existing at depths of 50-300km within subducting lithosphere. However, low pressure hydrous phases potentially abundant in subducting lithosphere (e.g. chlorite and antigorite) exhibit a temperature maximum in their stability, implying that the bulk volume change at depths of more than 70-100 km. becomes negative, thereby raising questions about mechanical instability upon dehydration. Further, it is now well-accepted that intermediate-depth earthquakes occur within the descending slab (double seismic zones present in several slabs dramatically demonstrate this fact), in conflict with the maximum depth of 10-12 km accepted for hydration of the lithosphere at oceanic spreading centers. Thus, on the one hand these earthquakes may be evidence that hydrous phases exist deep within subducting slabs but on the other hand, a mechanism for hydration to such depths is not known. One possibility is that large earthquakes outboard of trenches break the surface and allow hydration of the fault zone that can later dehydrate to yield earthquakes at depth, but no mechanism is known for pumping H2O into such fault zones to depths of tens of

  13. Effects on cardiovascular risk factors of weight losses limited to 5-10.

    PubMed

    Brown, Joshua D; Buscemi, Joanna; Milsom, Vanessa; Malcolm, Robert; O'Neil, Patrick M

    2016-09-01

    Little is known about the cardiovascular effects of modest weight loss. To determine whether weight losses limited to 5-10 % are sufficient to produce cardiovascular health benefits, data from 401 overweight and obese adults who enrolled in a behavioral weight loss program from 2003 to 2011 were analyzed. Primary outcomes were changes in fasting glucose, triglycerides, and cholesterol. Patients who lost 5-10 % showed significant reductions in triglycerides, total cholesterol, and low-density lipoprotein (LDL) cholesterol. Patients who lost >10 % experienced significantly greater improvements in triglycerides, total cholesterol, and LDL cholesterol than patients losing less. For higher-risk patients, those who lost 5-10 % significantly reduced fasting glucose, triglycerides, and total cholesterol; those who lost >10 % improved on all risk factors (except HDL cholesterol) and to a significantly greater degree than those losing less. Five to 10 % weight losses produced improvements in cardiovascular risk factors, but greater weight losses were associated with even greater improvement. PMID:27528523

  14. Depth of origin of magma in eruptions

    PubMed Central

    Becerril, Laura; Galindo, Ines; Gudmundsson, Agust; Morales, Jose Maria

    2013-01-01

    Many volcanic hazard factors - such as the likelihood and duration of an eruption, the eruption style, and the probability of its triggering large landslides or caldera collapses - relate to the depth of the magma source. Yet, the magma source depths are commonly poorly known, even in frequently erupting volcanoes such as Hekla in Iceland and Etna in Italy. Here we show how the length-thickness ratios of feeder dykes can be used to estimate the depth to the source magma chamber. Using this method, accurately measured volcanic fissures/feeder-dykes in El Hierro (Canary Islands) indicate a source depth of 11–15 km, which coincides with the main cloud of earthquake foci surrounding the magma chamber associated with the 2011–2012 eruption of El Hierro. The method can be used on widely available GPS and InSAR data to calculate the depths to the source magma chambers of active volcanoes worldwide. PMID:24067336

  15. Depth of origin of magma in eruptions.

    PubMed

    Becerril, Laura; Galindo, Ines; Gudmundsson, Agust; Morales, Jose Maria

    2013-01-01

    Many volcanic hazard factors--such as the likelihood and duration of an eruption, the eruption style, and the probability of its triggering large landslides or caldera collapses--relate to the depth of the magma source. Yet, the magma source depths are commonly poorly known, even in frequently erupting volcanoes such as Hekla in Iceland and Etna in Italy. Here we show how the length-thickness ratios of feeder dykes can be used to estimate the depth to the source magma chamber. Using this method, accurately measured volcanic fissures/feeder-dykes in El Hierro (Canary Islands) indicate a source depth of 11-15 km, which coincides with the main cloud of earthquake foci surrounding the magma chamber associated with the 2011-2012 eruption of El Hierro. The method can be used on widely available GPS and InSAR data to calculate the depths to the source magma chambers of active volcanoes worldwide. PMID:24067336

  16. Depth of origin of magma in eruptions.

    PubMed

    Becerril, Laura; Galindo, Ines; Gudmundsson, Agust; Morales, Jose Maria

    2013-09-26

    Many volcanic hazard factors--such as the likelihood and duration of an eruption, the eruption style, and the probability of its triggering large landslides or caldera collapses--relate to the depth of the magma source. Yet, the magma source depths are commonly poorly known, even in frequently erupting volcanoes such as Hekla in Iceland and Etna in Italy. Here we show how the length-thickness ratios of feeder dykes can be used to estimate the depth to the source magma chamber. Using this method, accurately measured volcanic fissures/feeder-dykes in El Hierro (Canary Islands) indicate a source depth of 11-15 km, which coincides with the main cloud of earthquake foci surrounding the magma chamber associated with the 2011-2012 eruption of El Hierro. The method can be used on widely available GPS and InSAR data to calculate the depths to the source magma chambers of active volcanoes worldwide.

  17. The estimation of 550 km x 550 km mean gravity anomalies. [from free atmosphere gravimetry data

    NASA Technical Reports Server (NTRS)

    Williamson, M. R.; Gaposchkin, E. M.

    1975-01-01

    The calculation of 550 km X 550 km mean gravity anomalies from 1 degree X 1 degree mean free-air gravimetry data is discussed. The block estimate procedure developed by Kaula was used, and estimates for 1452 of the 1654 blocks were obtained.

  18. Large Circular Basin - 1300-km diameter

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Close-up view of one-half of a 1300-km diameter circular basin the largest observed on Mercury. The other half is hidden beyond the terminator to the left. Hills and valleys extend in a radial fashion outward from the main ring. Interior of the large basin is completely flooded by plains materials; adjacent lowlands are also partially flooded and superimposed on the plains are bowl shaped craters. Wrinkle ridges are abundant on the plains materials. The area shown is 1008 miles (1600 km) from the top to the bottom of the picture. Sun's illumination is from the right. Blurred linear lines extending across the picture near bottom are missing data lines that have been filled in by the computer. Mariner 10 encountered Mercury on Friday, March 29th, 1974, passing the planet on the darkside 431 miles (690-km) from the surface.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    NOTE: This image was scanned from physical media.

  19. The Depth of Detachment Faulting at Mid-Ocean Ridges : Evidence From Zircon Geo- and Thermochronometry

    NASA Astrophysics Data System (ADS)

    Grimes, C. B.; John, B. E.; Cheadle, M. J.; Reiners, P. W.; Wooden, J. L.

    2008-12-01

    rates observed at other oceanic core complexes in the Atlantic and Indian Oceans) of 16 mm/yr. Previously published Pb/U and (U-Th)/He zircon ages from Atlantis Bank (SWIR) indicate a fault length of 7.7±3.8 km. Estimated length-scales for the active portion of several oceanic detachment faults therefore range from 5-10 km (between the 900° and 200° C isotherms). Using these calculated fault lengths, an estimated depth to the 200° C isotherm (1-2 km), and an assumed fault initiation dip of 50° (based on paleomagnetic data) we estimate that these faults were active to depths of up to 8 km (~8 km for Atlantis Massif and ODP site 1275, 5.5 km at ODP site 1270, and ~7 km for Atlantis Bank at ODP Hole 735B). These significant depths for active faulting in slow spreading environments are consistent with microseismicity studies, and the existence of high temperature fault rocks at many oceanic detachment faults.

  20. Design and mass production of the optical modules for KM3NeT-Italia project

    NASA Astrophysics Data System (ADS)

    Leonora, Emanuele; Aiello, Sebastiano; Giordano, Valentina

    2016-04-01

    The KM3NeT European project aims at constructing a km3 underwater neutrino telescope in the depths of the Mediterranean Sea. The first phase that is under construction will comprise eight tower-like detection structures (KM3NeT-Italia), which will form the internal core of a km3-scale detector. The detection element of KM3NeT-Italia, the optical module, is made of a 13-inch pressure-resistant glass-vessel that contains a single 10-inch photomultiplier and the relative electronics. The design of the whole optical module, the main results obtained from the massive photomultipliers measurements, and the foremost phases of the mass production procedure performed at the production site of Catania are also presented.

  1. MODIS aerosol product at 3 km spatial resolution for urban and air quality studies

    NASA Astrophysics Data System (ADS)

    Mattoo, S.; Remer, L. A.; Levy, R. C.; Holben, B. N.; Smirnov, A.

    2008-12-01

    The MODerate resolution Imaging Spectroradiometer (MODIS) aboard the Terra and Aqua satellites has been producing an aerosol product since early 2000. The original product reports aerosol optical depth and a variety of other aerosol parameters at a spatial resolution of 10 km over both land and ocean. The 10 km product is actually constructed from 500 m pixels, which permits a strict selection process to choose the "best" or "cleanest" pixels in each 10 km square for use in the aerosol retrieval. Thus, the original 10 km product provides a useful product, accurate in many applications. However, the 10 km product can miss narrow aerosol plumes and the spatial variability associated with urban air pollution. The MODIS aerosol team will be introducing a finer resolution aerosol product over land regions in the next release of the product (Collection 6). The new product will be produced at 3 km resolution. It is based on the same procedures as the original product and benefits from the same spatial variability criteria for finding and masking cloudy pixels. The 3 km product does capture the higher spatial variability associated with individual aerosol plumes. However, it is noisier than the 10 km product. Both products will be available operationally in Collection 6. The new 3km product offers new synergistic possibilities with PM2.5 monitoring networks, AERONET and various air quality models such as CMAQ.

  2. Laboratory 20-km cycle time trial reproducibility.

    PubMed

    Zavorsky, G S; Murias, J M; Gow, J; Kim, D J; Poulin-Harnois, C; Kubow, S; Lands, L C

    2007-09-01

    This study evaluated the reproducibility of laboratory based 20-km time trials in well trained versus recreational cyclists. Eighteen cyclists (age = 34 +/- 8 yrs; body mass index = 23.1 +/- 2.2 kg/m (2); VO(2max) = 4.19 +/- 0.65 L/min) completed three 20-km time trials over a month on a Velotron cycle ergometer. Average power output (PO) (W), speed, and heart rate (HR) were significantly lower in the first time trial compared to the second and third time trial. The coefficients of variation (CV) between the second and third trial of the top eight performers for average PO, time to completion, and speed were 1.2 %, 0.6 %, 0.5 %, respectively, compared to 4.8 %, 2.0 %, and 2.3 % for the bottom ten. In addition, the average HR, VO(2), and percentage of VO(2max) were similar between trials. This study demonstrated that (1) a familiarization session improves the reliability of the measurements (i.e., average PO, time to completion and speed), and (2) the CV was much smaller for the best performers.

  3. Global modeling with GEOS-5 from 50-km to 1-km with a single unified GCM

    NASA Astrophysics Data System (ADS)

    Putman, William; Suarez, Max; Molod, Andrea; Barahona, Donifan

    2015-04-01

    The Goddard Earth Observing System model (GEOS-5) of the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center is uniquely designed to adapt to increasing resolution. This supports application of GEOS-5 for decadal scale climate simulation and reanalysis with a horizontal resolution of 50-kilometers (km), high-resolution numerical weather prediction at 25- to 14-km, and global mesoscale modeling at resolutions of 7- to 1.5-km. Resolution-aware parameterizations and dynamics support this diverse portfolio of applications within a single unified GEOS-5 GCM code-base. We will discuss the adaptation of physics parameterizations with increasing resolution. This includes the role of deep convective parameterization, the move to an improved two-moment microphysics scheme, the need for shallow convective parameterization, and the role of non-hydrostatic dynamics and implicit/explicit damping. Parameterization and dynamics evaluation are explored not only in global integrations with GEOS-5 but with radiative convective equilibrium tests that permit the rapid exploration of high-resolution simulations in a smaller doubly periodic Cartesian domain. Simulation results will highlight intercomparisons of model biases in cloud forcing and precipitation from the 30-year 50-km MERRA-2 reanalysis, 50- to 25-km free-running AMIP simulations, a 2-year 7-km global mesoscale simulation, and monthly global simulations at 3.5-km. A global 1.5-km simulation with GEOS-5 highlights our pursuit of truly convection permitting global simulations with GEOS-5. The tuning evaluation for this simulation using doubly periodic radiative convective equilibrium experiments will be discussed.

  4. Improved Boundary Layer Depth Retrievals from MPLNET

    NASA Technical Reports Server (NTRS)

    Lewis, Jasper R.; Welton, Ellsworth J.; Molod, Andrea M.; Joseph, Everette

    2013-01-01

    Continuous lidar observations of the planetary boundary layer (PBL) depth have been made at the Micropulse Lidar Network (MPLNET) site in Greenbelt, MD since April 2001. However, because of issues with the operational PBL depth algorithm, the data is not reliable for determining seasonal and diurnal trends. Therefore, an improved PBL depth algorithm has been developed which uses a combination of the wavelet technique and image processing. The new algorithm is less susceptible to contamination by clouds and residual layers, and in general, produces lower PBL depths. A 2010 comparison shows the operational algorithm overestimates the daily mean PBL depth when compared to the improved algorithm (1.85 and 1.07 km, respectively). The improved MPLNET PBL depths are validated using radiosonde comparisons which suggests the algorithm performs well to determine the depth of a fully developed PBL. A comparison with the Goddard Earth Observing System-version 5 (GEOS-5) model suggests that the model may underestimate the maximum daytime PBL depth by 410 m during the spring and summer. The best agreement between MPLNET and GEOS-5 occurred during the fall and they diered the most in the winter.

  5. Oxygen depth profiling with subnanometre depth resolution

    NASA Astrophysics Data System (ADS)

    Kosmata, Marcel; Munnik, Frans; Hanf, Daniel; Grötzschel, Rainer; Crocoll, Sonja; Möller, Wolfhard

    2014-10-01

    A High-depth Resolution Elastic Recoil Detection (HR-ERD) set-up using a magnetic spectrometer has been taken into operation at the Helmholtz-Zentrum Dresden-Rossendorf for the first time. This instrument allows the investigation of light elements in ultra-thin layers and their interfaces with a depth resolution of less than 1 nm near the surface. As the depth resolution is highly influenced by the experimental measurement parameters, sophisticated optimisation procedures have been implemented. Effects of surface roughness and sample damage caused by high fluences need to be quantified for each kind of material. Also corrections are essential for non-equilibrium charge state distributions that exist very close to the surface. Using the example of a high-k multilayer SiO2/Si3N4Ox/SiO2/Si it is demonstrated that oxygen in ultra-thin films of a few nanometres thickness can be investigated by HR-ERD.

  6. Curie Depth Analysis of the Salton Sea Region, Southern California

    NASA Astrophysics Data System (ADS)

    Mickus, Kevin; Hussein, Musa

    2016-02-01

    Aeromagnetic data were analyzed to determine the bottom of magnetic bodies that might be related to the Curie point depth (CPD) by 2D spectral and 3D inversion methods within the Salton Trough and the surrounding region in southern California. The bottom of the magnetic bodies for 55 × 55 km windows varied in depth between 11 and 23 km in depth using 2D spectral methods. Since the 55 × 55 km square window may include both shallow and deep source, a 3D inversion method was used to provide better resolution of the bottom of the magnetic bodies. The 3D models indicate the depth to the bottom of the magnetic bodies varied between 5 and 23 km. Even though both methods produced similar results, the 3D inversion method produced higher resolution of the CPD depths. The shallowest depths (5-8 km) occur along and west of the Brawley Seismic Zone and the southwestern portion of the Imperial Valley. The source of these shallow CPD values may be related to geothermal systems including hydrothermal circulation and/or partially molten material. Additionally, shallow CPD depths (7-12 km) were found in a northwest-trending zone in the center of the Salton Trough. These depths coincide with previous seismic analyses that indicated a lower crustal low velocity region which is believed to be caused by partially molten material. Lower velocity zones in several regions may be related to fracturing and/or hydrothermal fluids. If the majority of these shallow depths are related to temperature, they are likely associated with the CPD, and the partially molten material extends over a wider zone than previously known. Greater depths within the Salton Trough coincide with the base of basaltic material and/or regions of intense metamorphism intruded by mafic material in the middle/lower crust.

  7. Evidence for Extended (5-10 Ma) Emplacement of Ferrar Dolerite from 40Ar-39Ar Geochronology

    NASA Astrophysics Data System (ADS)

    Knight, K. B.; Renne, P. R.

    2005-12-01

    Antarctica's Ferrar large igneous province (LIP) is dominated by dolerites linked in time, space and geochemical character with the nearby Kirkpatrick basalts, and more broadly, with magmas preserved in Dronning Maud Land (Antarctica), the Karoo LIP (southern Africa) and the Chon Aike LIP (Patagonia). Together, these magmatic bodies represent an estimated emplacement volume of ~3 x 106 km3, correlated with the break-up and post-break-up activity of the Gondwana supercontinent in the middle Jurassic. Plagioclase separates from 9 Ferrar dolerites exposed across the Dry Valleys of the Transantarctic Mountains were analyzed using the 40Ar-39Ar method. Detailed apparent age spectra reveal a range of well-defined plateau ages. Four samples yield indistinguishable ages with a weighted mean age 180.0 ± 0.5 Ma. The remaining 5 samples yield statistically distinct and significantly younger plateau ages, decreasing to as young as ca. 173 Ma. These ages may represent emplacement and/or cooling ages (below ~300°C, the approximate closure temperature for argon in plagioclase). Spectacular exposure and preservation of the Ferrar intrusive complex has led to increased interest in development of models of magma mush formation and emplacement. These data provide quantitative constraints for models of magma emplacement for the Ferrar, suggesting either the presence of long-lived magma chambers or sufficient thermal insulation or input to allow heterogeneous slow cooling of the Ferrar dolerites. The suggestion of protracted (5-10 Ma) intrusive activity supports previous geochronology data reported from Dronning Maud Land and the Ferrar, as well as the broad temporal picture arising around the time of Gondwana break-up.

  8. Improved Blocking at 25km Resolution?

    NASA Astrophysics Data System (ADS)

    Schiemann, R.; Demory, M. E.; Mizielinski, M.; Roberts, M.; Shaffrey, L.; Strachan, J.; Vidale, P. L.; Matsueda, M.

    2014-12-01

    It has been suggested that relatively coarse resolution of atmospheric general circulation models (AGCMs) limits their ability to represent mid-latitude blocking. Assessing the role of model resolution for blocking is computationally expensive, as multi-decadal simulations at the desired resolution are necessary for a robust estimation of blocking statistics. Here, we use an ensemble of three atmosphere-only global models for which simulations that fulfil this requirement are available at resolutions of roughly 25km horizontal grid spacing in the mid-latitudes. This corresponds to about a fourfold increase in resolution over the highest-resolution CMIP5 (Coupled Model Intercomparison Project, Phase 5) models. The three models are (i) the ECMWF model (IFS) as used in the project Athena, (ii) the MRI-AGCM 3.2, and (iii) our own HadGEM3-GA3 simulations obtained in the UPSCALE project (UK on PrACE - weather-resolving Simulations of Climate for globAL Environmental risk). We use a two-dimensional blocking index to assess the representation of blocking in these simulations and in three reanalyses (ERA-Interim, ERA-40, MERRA). We evaluate the spatial distribution of climatological blocking frequency, the interannual variability of blocking occurrence as well as the persistence of blocking events. Furthermore, the degree to which blocking biases are associated with mean-state biases is quantified in the different models. We find that the representation of blocking remains very sensitive to atmospheric resolution as the grid spacing is reduced to about 25km. The simulated blocking frequency increases with resolution, mostly so as to reduce the model bias, yet there is considerable variation between the results obtained for different models, seasons, and for the Atlantic and Pacific regions.

  9. Structural distortions in 5-10 nm silver nanoparticles under high pressure

    SciTech Connect

    Koski, Kristie J.; Kamp, Noelle M.; Kunz, Martin; Knight, Jason K.; Alivisatos, A.P.; Smith, R.K.

    2008-10-13

    We present experimental evidence that silver nanoparticles in the size range of 5-10 nm undergo a reversible structural transformation under hydrostatic pressures up to 10 GPa. We have used x-ray diffraction with a synchrotron light source to investigate pressure-dependent and size-dependent trends in the crystal structure of silver nanoparticles in a hydrostatic medium compressed in a diamond-anvil cell. Results suggest a reversible linear pressure-dependent rhombohedral distortion which has not been previously observed in bulk silver. We propose a mechanism for this transition that considers the bond-length distribution in idealized multiply twinned icosahedral particles. To further support this hypothesis, we also show that similar measurements of single-crystal platinum nanoparticles reveal no such distortions.

  10. Warm-hot baryons comprise 5-10 per cent of filaments in the cosmic web.

    PubMed

    Eckert, Dominique; Jauzac, Mathilde; Shan, HuanYuan; Kneib, Jean-Paul; Erben, Thomas; Israel, Holger; Jullo, Eric; Klein, Matthias; Massey, Richard; Richard, Johan; Tchernin, Céline

    2015-12-01

    Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe's total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter density is larger than average) as a low-density plasma at temperatures of 10(5)-10(7) kelvin, known as the warm-hot intergalactic medium. There have been previous claims of the detection of warm-hot baryons along the line of sight to distant blazars and of hot gas between interacting clusters. These observations were, however, unable to trace the large-scale filamentary structure, or to estimate the total amount of warm-hot baryons in a representative volume of the Universe. Here we report X-ray observations of filamentary structures of gas at 10(7) kelvin associated with the galaxy cluster Abell 2744. Previous observations of this cluster were unable to resolve and remove coincidental X-ray point sources. After subtracting these, we find hot gas structures that are coherent over scales of 8 megaparsecs. The filaments coincide with over-densities of galaxies and dark matter, with 5-10 per cent of their mass in baryonic gas. This gas has been heated up by the cluster's gravitational pull and is now feeding its core. Our findings strengthen evidence for a picture of the Universe in which a large fraction of the missing baryons reside in the filaments of the cosmic web. PMID:26632589

  11. Seven novel mutations at the 5,10-methylenetetrahydrofolate reductase locus

    SciTech Connect

    Goyette, P.; Frosst, P.; Rosenblatt, D.S.; Rozen, R.

    1994-09-01

    5,10-methylenetetrahydrofolate reductase (MTHFR), a flavoprotein, catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a cofactor for methionine synthase in the methylation of homocysteine to methionine. Severe MTHFR deficiency, which causes homocysteinemia, is an autosomal recessive disorder with variable clinical features; developmental delay, perinatal death, mental retardation and asymptomatic individuals have been observed. A milder deficiency has been reported in patients with cardiovascular disease. We have recently described the isolation of a cDNA for MTHFR and the identification of 2 mutations in patients with severe MTHFR deficiency. We report here the characterization of 7 additional mutations at this locus: 5 missense mutations and 2 splicing mutations. Mutation analysis was performed by SSCP on PCR products generated either from reverse transcription-PCR of patients` total fibroblast RNA or from PCR of patients` genomic DNA. The 5 missense mutations are as follows: 1 Arg to Cys substitution in a hydrophilic segment proposed to be the hinge region that connects the catalytic and regulatory domains, 2 different Arg to Cys substitutions in 2 patients whose enzymatic thermolability is responsive to FAD, 1 Thr to Met substitution affecting an evolutionarily-conserved residue and a Pro to Leu substitution. The 2 splicing mutations affect the 5{prime} splice site and the 3{prime} splice site of 2 introns, respectively. The 5{prime} splice site mutation generates a 57 bp in-frame deletion of the RNA through the utilization of a cryptic 5{prime} splice site within the coding sequence. The identification of 9 mutations at this locus has allowed us to make preliminary correlations between genotype and phenotype and to contribute to a structure:function analysis of the enzyme.

  12. Warm-hot baryons comprise 5-10 per cent of filaments in the cosmic web.

    PubMed

    Eckert, Dominique; Jauzac, Mathilde; Shan, HuanYuan; Kneib, Jean-Paul; Erben, Thomas; Israel, Holger; Jullo, Eric; Klein, Matthias; Massey, Richard; Richard, Johan; Tchernin, Céline

    2015-12-01

    Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe's total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter density is larger than average) as a low-density plasma at temperatures of 10(5)-10(7) kelvin, known as the warm-hot intergalactic medium. There have been previous claims of the detection of warm-hot baryons along the line of sight to distant blazars and of hot gas between interacting clusters. These observations were, however, unable to trace the large-scale filamentary structure, or to estimate the total amount of warm-hot baryons in a representative volume of the Universe. Here we report X-ray observations of filamentary structures of gas at 10(7) kelvin associated with the galaxy cluster Abell 2744. Previous observations of this cluster were unable to resolve and remove coincidental X-ray point sources. After subtracting these, we find hot gas structures that are coherent over scales of 8 megaparsecs. The filaments coincide with over-densities of galaxies and dark matter, with 5-10 per cent of their mass in baryonic gas. This gas has been heated up by the cluster's gravitational pull and is now feeding its core. Our findings strengthen evidence for a picture of the Universe in which a large fraction of the missing baryons reside in the filaments of the cosmic web.

  13. Moho depth and age in southern Norway

    NASA Astrophysics Data System (ADS)

    Stratford, W.; Thybo, H.

    2010-05-01

    Moho ages beneath the Fennoscandian shield are highly variable due to the method of crustal accretion and to the long history of extensional and compressional tectonics. In southern Norway, the Moho and crust are inferred to be the youngest of the shield, however, it is likely that a large discrepancy between crustal age and Moho age exists beneath the high southern scandes where the Caledonian orogeny was in effect. Moho structure in southern Norway was targeted recently with a seismic refraction study (Magnus-Rex - Mantle investigations of Norwegian uplift Structure, refraction experiment). Three ~400 km long active source seismic profiles across the high southern Scandes Mountains, the youngest section of the Fennoscandian shield were recorded. Moho depths beneath the high mountains are 36-40 km, thinning towards the Atlantic Margin and the Oslo graben. A new Moho depth map is constructed for southern Norway by compiling new depth measurements with previous refraction Moho measurements. Gaining better constraint on Moho depths in this area is timely, as debate over the source of support for the mountains has provided the impetus for a new focus project, TopoScandesdeep, to find the depth and mechanisms of compensation. P and S-wave arrivals were recorded in the Magnus-Rex project, from which Poisson ratios for the crust in southern Norway are calculated. Unusually strong S-wave arrivals allow rare insight into crustal Poisson's ratio structure that is not normally available from active source data and are usually determined by earthquake tomography studies where only bulk crustal values are available. An average Poisson's ratio of 0.25 is calculated for the crust in southern Norway, suggesting it is predominantly of felsic-intermediate composition and lacks any significant mafic lower crust. This differs significantly from the adjacent crust in the Svecofennian domain of the Fennoscandian shield where Moho depths reach ~50 km and an up to 20 km thick mafic lower

  14. 45 Km Horizontal Path Optical Link Experiment

    NASA Technical Reports Server (NTRS)

    Biswas, A.; Ceniceros, J.; Novak, M.; Jeganathan, M.; Portillo, A.; Erickson, D.; Depew, J.; Sanii, B.; Lesh, J. R.

    2000-01-01

    Mountain-top to mountain-top optical link experiments have been initiated at JPL, in order to perform a systems level evaluation of optical communications. Progress made so far is reported. ne NASA, JPL developed optical communications demonstrator (OCD) is used to transmit a laser signal from Strawberry Peak (SP), located in the San Bernadino mountains of California. This laser beam is received by a 0.6 m aperture telescope at JPL's Table Mountain Facility (TMF), located in Wrightwood, California. The optical link is bi-directional with the TMF telescope transmitting a continuous 4-wave (cw) 780 run beacon and the OCD sending back a 840 nm, 100 - 500 Mbps pseudo noise (PN) modulated, laser beam. The optical link path is at an average altitude of 2 km above sea level, covers a range of 46.8 km and provides an atmospheric channel equivalent to approx. 4 air masses. Average received power measured at either end fall well within the uncertainties predicted by link analysis. The reduction in normalized intensity variance (sigma(sup 2, sub I)) for the 4-beam beacon, compared to each individual beam, at SP, was from approx. 0.68 to 0.22. With some allowance for intra-beam mis-alignment, this is consistent with incoherent averaging. The sigma(sup2, sub I) measured at TMF approx. 0.43 +/- 0.22 exceeded the expected aperture averaged value of less than 0.1, probably because of beam wander. The focused spot sizes of approx. 162 +/- 6 microns at the TMF Coude and approx. 64 +/- 3 microns on the OCD compare to the predicted size range of 52 - 172 microns and 57 - 93 microns, respectively. This is consistent with 4 - 5 arcsec of atmospheric "seeing". The preliminary evaluation of OCD's fine tracking indicates that the uncompensated tracking error is approx. 3.3 micro rad compared to approx. 1.7 micro rad observed in the laboratory. Fine tracking performance was intermittent, primarily due to beacon fades on the OCD tracking sensor. The best bit error rates observed while

  15. Stereoscopic depth constancy

    PubMed Central

    Guan, Phillip

    2016-01-01

    Depth constancy is the ability to perceive a fixed depth interval in the world as constant despite changes in viewing distance and the spatial scale of depth variation. It is well known that the spatial frequency of depth variation has a large effect on threshold. In the first experiment, we determined that the visual system compensates for this differential sensitivity when the change in disparity is suprathreshold, thereby attaining constancy similar to contrast constancy in the luminance domain. In a second experiment, we examined the ability to perceive constant depth when the spatial frequency and viewing distance both changed. To attain constancy in this situation, the visual system has to estimate distance. We investigated this ability when vergence, accommodation and vertical disparity are all presented accurately and therefore provided veridical information about viewing distance. We found that constancy is nearly complete across changes in viewing distance. Depth constancy is most complete when the scale of the depth relief is constant in the world rather than when it is constant in angular units at the retina. These results bear on the efficacy of algorithms for creating stereo content. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269596

  16. Stereoscopic depth constancy.

    PubMed

    Guan, Phillip; Banks, Martin S

    2016-06-19

    Depth constancy is the ability to perceive a fixed depth interval in the world as constant despite changes in viewing distance and the spatial scale of depth variation. It is well known that the spatial frequency of depth variation has a large effect on threshold. In the first experiment, we determined that the visual system compensates for this differential sensitivity when the change in disparity is suprathreshold, thereby attaining constancy similar to contrast constancy in the luminance domain. In a second experiment, we examined the ability to perceive constant depth when the spatial frequency and viewing distance both changed. To attain constancy in this situation, the visual system has to estimate distance. We investigated this ability when vergence, accommodation and vertical disparity are all presented accurately and therefore provided veridical information about viewing distance. We found that constancy is nearly complete across changes in viewing distance. Depth constancy is most complete when the scale of the depth relief is constant in the world rather than when it is constant in angular units at the retina. These results bear on the efficacy of algorithms for creating stereo content.This article is part of the themed issue 'Vision in our three-dimensional world'.

  17. Teleportation of entanglement over 143 km.

    PubMed

    Herbst, Thomas; Scheidl, Thomas; Fink, Matthias; Handsteiner, Johannes; Wittmann, Bernhard; Ursin, Rupert; Zeilinger, Anton

    2015-11-17

    As a direct consequence of the no-cloning theorem, the deterministic amplification as in classical communication is impossible for unknown quantum states. This calls for more advanced techniques in a future global quantum network, e.g., for cloud quantum computing. A unique solution is the teleportation of an entangled state, i.e., entanglement swapping, representing the central resource to relay entanglement between distant nodes. Together with entanglement purification and a quantum memory it constitutes a so-called quantum repeater. Since the aforementioned building blocks have been individually demonstrated in laboratory setups only, the applicability of the required technology in real-world scenarios remained to be proven. Here we present a free-space entanglement-swapping experiment between the Canary Islands of La Palma and Tenerife, verifying the presence of quantum entanglement between two previously independent photons separated by 143 km. We obtained an expectation value for the entanglement-witness operator, more than 6 SDs beyond the classical limit. By consecutive generation of the two required photon pairs and space-like separation of the relevant measurement events, we also showed the feasibility of the swapping protocol in a long-distance scenario, where the independence of the nodes is highly demanded. Because our results already allow for efficient implementation of entanglement purification, we anticipate our research to lay the ground for a fully fledged quantum repeater over a realistic high-loss and even turbulent quantum channel.

  18. Teleportation of entanglement over 143 km

    PubMed Central

    Herbst, Thomas; Scheidl, Thomas; Fink, Matthias; Handsteiner, Johannes; Wittmann, Bernhard; Ursin, Rupert; Zeilinger, Anton

    2015-01-01

    As a direct consequence of the no-cloning theorem, the deterministic amplification as in classical communication is impossible for unknown quantum states. This calls for more advanced techniques in a future global quantum network, e.g., for cloud quantum computing. A unique solution is the teleportation of an entangled state, i.e., entanglement swapping, representing the central resource to relay entanglement between distant nodes. Together with entanglement purification and a quantum memory it constitutes a so-called quantum repeater. Since the aforementioned building blocks have been individually demonstrated in laboratory setups only, the applicability of the required technology in real-world scenarios remained to be proven. Here we present a free-space entanglement-swapping experiment between the Canary Islands of La Palma and Tenerife, verifying the presence of quantum entanglement between two previously independent photons separated by 143 km. We obtained an expectation value for the entanglement-witness operator, more than 6 SDs beyond the classical limit. By consecutive generation of the two required photon pairs and space-like separation of the relevant measurement events, we also showed the feasibility of the swapping protocol in a long-distance scenario, where the independence of the nodes is highly demanded. Because our results already allow for efficient implementation of entanglement purification, we anticipate our research to lay the ground for a fully fledged quantum repeater over a realistic high-loss and even turbulent quantum channel. PMID:26578764

  19. Teleportation of entanglement over 143 km.

    PubMed

    Herbst, Thomas; Scheidl, Thomas; Fink, Matthias; Handsteiner, Johannes; Wittmann, Bernhard; Ursin, Rupert; Zeilinger, Anton

    2015-11-17

    As a direct consequence of the no-cloning theorem, the deterministic amplification as in classical communication is impossible for unknown quantum states. This calls for more advanced techniques in a future global quantum network, e.g., for cloud quantum computing. A unique solution is the teleportation of an entangled state, i.e., entanglement swapping, representing the central resource to relay entanglement between distant nodes. Together with entanglement purification and a quantum memory it constitutes a so-called quantum repeater. Since the aforementioned building blocks have been individually demonstrated in laboratory setups only, the applicability of the required technology in real-world scenarios remained to be proven. Here we present a free-space entanglement-swapping experiment between the Canary Islands of La Palma and Tenerife, verifying the presence of quantum entanglement between two previously independent photons separated by 143 km. We obtained an expectation value for the entanglement-witness operator, more than 6 SDs beyond the classical limit. By consecutive generation of the two required photon pairs and space-like separation of the relevant measurement events, we also showed the feasibility of the swapping protocol in a long-distance scenario, where the independence of the nodes is highly demanded. Because our results already allow for efficient implementation of entanglement purification, we anticipate our research to lay the ground for a fully fledged quantum repeater over a realistic high-loss and even turbulent quantum channel. PMID:26578764

  20. Depressed mantle discontinuities beneath Iceland: Evidence of a garnet controlled 660 km discontinuity?

    NASA Astrophysics Data System (ADS)

    Jenkins, J.; Cottaar, S.; White, R. S.; Deuss, A.

    2016-01-01

    The presence of a mantle plume beneath Iceland has long been hypothesised to explain its high volumes of crustal volcanism. Practical constraints in seismic tomography mean that thin, slow velocity anomalies representative of a mantle plume signature are difficult to image. However it is possible to infer the presence of temperature anomalies at depth from the effect they have on phase transitions in surrounding mantle material. Phase changes in the olivine component of mantle rocks are thought to be responsible for global mantle seismic discontinuities at 410 and 660 km depth, though exact depths are dependent on surrounding temperature conditions. This study uses P to S seismic wave conversions at mantle discontinuities to investigate variation in topography allowing inference of temperature anomalies within the transition zone. We employ a large data set from a wide range of seismic stations across the North Atlantic region and a dense network in Iceland, including over 100 stations run by the University of Cambridge. Data are used to create over 6000 receiver functions. These are converted from time to depth including 3D corrections for variations in crustal thickness and upper mantle velocity heterogeneities, and then stacked based on common conversion points. We find that both the 410 and 660 km discontinuities are depressed under Iceland compared to normal depths in the surrounding region. The depression of 30 km observed on the 410 km discontinuity could be artificially deepened by un-modelled slow anomalies in the correcting velocity model. Adding a slow velocity conduit of -1.44% reduces the depression to 18 km; in this scenario both the velocity reduction and discontinuity topography reflect a temperature anomaly of 210 K. We find that much larger velocity reductions would be required to remove all depression on the 660 km discontinuity, and therefore correlated discontinuity depressions appear to be a robust feature of the data. While it is not possible

  1. KM3NeT tower data acquisition and data transport electronics

    NASA Astrophysics Data System (ADS)

    Nicolau, C. A.; Ameli, F.; Biagioni, A.; Capone, A.; Frezza, O.; Lonardo, A.; Masullo, R.; Mollo, C. M.; Orlando, A.; Simeone, F.; Vicini, P.

    2016-04-01

    In the framework of the KM3Net European project, the production stage of a large volume underwater neutrino telescope has started. The forthcoming installation includes 8 towers and 24 strings, that will be installed 100 km off-shore Capo Passero (Italy) at 3500 m depth. The KM3NeT tower, whose layout is strongly based on the NEMO Phase-2 prototype tower deployed in March 2013, has been re-engineered and partially re-designed in order to optimize production costs, power consumption, and usability. This contribution gives a description of the main electronics, including front-end, data transport and clock distribution system, of the KM3NeT tower detection unit.

  2. Motivation with Depth.

    ERIC Educational Resources Information Center

    DiSpezio, Michael A.

    2000-01-01

    Presents an illusional arena by offering experience in optical illusions in which students must apply critical analysis to their innate information gathering systems. Introduces different types of depth illusions for students to experience. (ASK)

  3. On the 300km discontinuity with Conversion Phases SdP in the Tonga-Fiji Region

    NASA Astrophysics Data System (ADS)

    Zhou, Y.; Sui, Y.

    2011-12-01

    Conversion phases SdP are powerful for retrieving information of velocity interfaces of deep structure of Earth's interior. The high sensitivity seismograph network Japan (Hi-net) has about 800 seismometers which can provide digital waveform data from since 2004 through internet. The difference between the focal depths and the depth of 300 km discontinuity determines the sizes of Fresnel zones at the discontinuity for the waveform data from the seismic network, so seismic waveform of six earthquakes with depths from 145 to 220km between 2004 and 2011 beneath Tonga-Fiji region are retrieved from Hi-net (www.hinet.bosai.go.jp). The magnitudes of the events used are Mb 5.0-5.7 which means there are good signal-noise ratios and relatively simple source time functions. In this study, the focal depths determined with pP phases are provided by EHB database for those before 2006 and www.globalcmt.org for those after that year. After filtering with 0.2-1.0Hz (e.g. Castle and Creager, JGR, 2000) and manually selection, waveform data are divided to 5-8 groups related to the regional locations of seismometers and proceeded with N-th root slant-stack method, then we can get the related vespegram in differential time vs slowness. There are 38 vespegrams for 6 events. From the vespegrams, the conversion phases are picked according to the references of the theoretical values of the differential times and slownesses. The parameters read from vespegrams are inverted with IASP91 model to the depths and locations of conversion points. The conversion points related to 300 km discontinuity are distributed from 302 to 328km in the Fuji-Tonga region. For the vespegrams from one certain event but sub-networks, the depth variation are less than 20 km, mostly are less than 11km. Especially, the depth variation of the event 6 are just 8 km. So in the square region with 200 * 300 km, the lateral variation of the depth of the 300 km discontinuity is relatively small. Comparing with the former

  4. Depth Optimization Study

    DOE Data Explorer

    Kawase, Mitsuhiro

    2009-11-22

    The zipped file contains a directory of data and routines used in the NNMREC turbine depth optimization study (Kawase et al., 2011), and calculation results thereof. For further info, please contact Mitsuhiro Kawase at kawase@uw.edu. Reference: Mitsuhiro Kawase, Patricia Beba, and Brian Fabien (2011), Finding an Optimal Placement Depth for a Tidal In-Stream Conversion Device in an Energetic, Baroclinic Tidal Channel, NNMREC Technical Report.

  5. 5,10 Methylenetetrahydrofolate reductase genetic polymorphism as a risk factor for neural tube defects

    SciTech Connect

    Ou, C.Y.; Brown, V.K.; Khoury, M.J.

    1996-06-28

    Persons with a thermolabile form of the enzyme 5,10 methylenetetrahydrofolate reductase (MTHFR) have reduced enzyme activity and increased plasma homocysteine which can be lowered by supplemental folic acid. Thermolability of the enzyme has recently been shown to be caused by a common mutation (677C{sup {r_arrow}}T) in the MTHFR gene. We studied 41 fibroblast cultures from NTD-affected fetuses and compared their genotypes with those of 109 blood specimens from individuals in the general population. 677C{sup {r_arrow}}T homozygosity was associated with a 7.2 fold increased risk for NTDs (95% confidence interval: 1.8-30.3; p value: 0.001). These preliminary data suggest that the 677C{sup {r_arrow}}T polymorphism of the MTHFR gene is a risk factor for spina bifida and anencephaly that may provide a partial biologic explanation for why folic acid prevents these types of NTD. 13 refs., 1 fig., 1 tab.

  6. Folate metabolism gene 5,10-methylenetetrahydrofolate reductase (MTHFR) is associated with ADHD in myelomeningocele patients.

    PubMed

    Spellicy, Catherine J; Northrup, Hope; Fletcher, Jack M; Cirino, Paul T; Dennis, Maureen; Morrison, Alanna C; Martinez, Carla A; Au, Kit Sing

    2012-01-01

    The objective of this study was to examine the relation between the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene and behaviors related to attention- deficit/hyperactivity disorder (ADHD) in individuals with myelomeningocele. The rationale for the study was twofold: folate metabolizing genes, (e.g. MTHFR), are important not only in the etiology of neural tube defects but are also critical to cognitive function; and individuals with myelomeningocele have an elevated incidence of ADHD. Here, we tested 478 individuals with myelomeningocele for attention-deficit hyperactivity disorder behavior using the Swanson Nolan Achenbach Pelham-IV ADHD rating scale. Myelomeningocele participants in this group for whom DNAs were available were genotyped for seven single nucleotide polymorphisms (SNPs) in the MTHFR gene. The SNPs were evaluated for an association with manifestation of the ADHD phenotype in children with myelomeningocele. The data show that 28.7% of myelomeningocele participants exhibit rating scale elevations consistent with ADHD; of these 70.1% had scores consistent with the predominantly inattentive subtype. In addition, we also show a positive association between the SNP rs4846049 in the 3'-untranslated region of the MTHFR gene and the attention-deficit hyperactivity disorder phenotype in myelomeningocele participants. These results lend further support to the finding that behavior related to ADHD is more prevalent in patients with myelomeningocele than in the general population. These data also indicate the potential importance of the MTHFR gene in the etiology of the ADHD phenotype. PMID:23227261

  7. Multiplicity of the 660-km discontinuity beneath the Izu-Bonin area

    NASA Astrophysics Data System (ADS)

    Zhou, Yuan-Ze; Yu, Xiang-Wei; Yang, Hui; Zang, Shao-Xian

    2012-05-01

    The relatively simple subducting slab geometry in the Izu-Bonin region provides a valuable opportunity to study the multiplicity of the 660-km discontinuity and the related response of the subducting slab on the discontinuity. Vertical short-period recordings of deep events with simple direct P phases beneath the Izu-Bonin region were retrieved from two seismic networks in the western USA and were used to study the structure of the 660-km discontinuity. After careful selection and pre-processing, 23 events from the networks, forming 32 pairs of event-network records, were processed. Related vespagrams were produced using the N-th root slant stack method for detecting weak down-going SdP phases that were inverted to the related conversion points. From depth histograms and the spatial distribution of the conversion points, there were three clear interfaces at depths of 670, 710 and 730 km. These interfaces were depressed approximately 20-30 km in the northern region. In the southern region, only two layers were identified in the depth histograms, and no obvious layered structure could be observed from the distribution of the conversion points.

  8. Warm-hot baryons comprise 5-10 per cent of filaments in the cosmic web

    NASA Astrophysics Data System (ADS)

    Eckert, Dominique; Jauzac, Mathilde; Shan, Huanyuan; Kneib, Jean-Paul; Erben, Thomas; Israel, Holger; Jullo, Eric; Klein, Matthias; Massey, Richard; Richard, Johan; Tchernin, Céline

    2015-12-01

    Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe’s total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter density is larger than average) as a low-density plasma at temperatures of 105-107 kelvin, known as the warm-hot intergalactic medium. There have been previous claims of the detection of warm-hot baryons along the line of sight to distant blazars and of hot gas between interacting clusters. These observations were, however, unable to trace the large-scale filamentary structure, or to estimate the total amount of warm-hot baryons in a representative volume of the Universe. Here we report X-ray observations of filamentary structures of gas at 107 kelvin associated with the galaxy cluster Abell 2744. Previous observations of this cluster were unable to resolve and remove coincidental X-ray point sources. After subtracting these, we find hot gas structures that are coherent over scales of 8 megaparsecs. The filaments coincide with over-densities of galaxies and dark matter, with 5-10 per cent of their mass in baryonic gas. This gas has been heated up by the cluster’s gravitational pull and is now feeding its core. Our findings strengthen evidence for a picture of the Universe in which a large fraction of the missing baryons reside in the filaments of the cosmic web.

  9. Kokes Awards for the 22nd North American Catalysis Society Meeting, June 5-10, 2011

    SciTech Connect

    Fabio H. Ribeiro

    2011-06-05

    The biennial North American Catalysis Society (NACS) Meetings are the premiere conferences in the area of catalysis, surface science, and reaction engineering. The 22nd meeting will be held the week of June 5-10, 2011 in Detroit, Michigan. The objective of the Meetings is to bring together leading researchers for intensive scientific exchange and interactions. Financial support that offsets some of the associated costs (specifically, registration fee, airline tickets, and hotel accommodations) would encourage graduate students, and for the first time undergraduate students, to attend and participate meaningfully in this conference. The funds sought in this proposal will help support the Richard J. Kokes Travel Award program. Graduate students eligible for these merit-based Awards are those who study at a North American university and who will present at the Meeting. We have currently 209 applications and we expect to be able to fund about half of them. The NACS has traditionally sought to encourage graduate student, and this year for the first time undergraduate studies, participation at the National Meetings and providing financial support is the most effective means to do so. Their attendance would contribute significantly to their scientific training and communication and presentation skills. They would be exposed to the leading researchers from the US and abroad; they would meet their peers from other universities; they would learn about cutting-edge results that could benefit their research projects; and they may become interested in becoming active participants in the catalysis community. These young investigators represent the next generation of scientists and engineers, and their proper training will lead to future scientific breakthroughs and technological innovations that benefit the US economy. Advances in catalysis can come in the form of more energy-efficient and environmentally-friendly chemical processes, improved fuel cell performance, efficient

  10. Lunar thermal regime to 300 km. [in crust and upper mantle

    NASA Technical Reports Server (NTRS)

    Keihm, S. J.; Langseth, M. G.

    1977-01-01

    Coupling of the global heat flow, crustal heat source enrichment, thermal conductivity, and temperature in the crust and upper mantle of the moon is examined. A steady-state moon in which conductive heat transfer dominates is assumed. Heat-flow measurements from the Apollo 15 and 17 missions and gamma-ray mapping of thorium conducted by the Apollo 15 and 16 missions provide data for the study of the lunar thermal regime. Temperatures in the range of 1100 to 1600 K are found for the 300-km depth level. In the upper mantle, temperature gradients are in the range of 1.8 to 3.2 K/km.

  11. 1990 ACSM-ASPRS Fall Convention, Anaheim, CA, Nov. 5-10, 1990, Technical Papers

    SciTech Connect

    Not Available

    1990-01-01

    The present conference on surveying, mapping, photogrammetry, and remote sensing encompasses the U.S. Geological Survey (USGS), the North American Vertical Datum (NAVD), the Geographic Information System and geodetic control, developments in geodetic surveying, and applications for remote sensing and photogrammetric techniques. Specific issues addressed include federal coordination of mapping, a USGS data format, the use of NAVD for flood insurance assessment, geodetic reference upgrades, the Airborne Data Acquisition and Registration system, conducting inventories of wetlands with remote sensing, chronologically evaluating urban growth, and analyzing substrate type and water depth with SPOT imagery. Also addressed are vehicle crush measurements via photogrammetry, the role of remote sensing in comprehensive environmental planning, watershed characterization using the Landsat TM, hardwoods identification with Landsat TM data, image motion effects, and computer modeling of urban area detection.

  12. Role of the transition zone and 660 km discontinuity in mantle dynamics

    NASA Astrophysics Data System (ADS)

    Ringwood, A. E.

    1994-10-01

    Recent seismic evidence suggests that subducted slabs experience resistance to further descent when they encounter the 660 km seismic discontinuity. Several possible causes of this resistance are evaluated. It is concluded that the chemical composition of the lower mantle is similar to that of the upper mantle, and that compositional change is therefore unlikely to be the cause of resistance to slab penetration. The proposal that a large increase of viscosity at the 660 km discontinuity impedes descending slabs is also rejected. However, three other factors are identified, each of which is capable of causing substantial resistance to descending slabs: (1) the negative slope of the transformation of silicate spinel to Mg-perovskite+magnesiowuestite; (2) differentiation of oceanic lithosphere into basaltic and depleted peridotitic layers, causing the slab to be buoyant compared with surrounding mantle pyrolite between depths of 660-800 km; (3) the accumulation of former oceanic crust to produce a gravitationally stable layer of garnetite (about 50 km thick) on top of the 660 km discontinuity. The combined effects of these sources of resistance provide a filter for subducted slabs. Those slabs with seismic zones extending below 600 km may possess sufficient negative buoyancy and strength to overcome the barriers and penetrate into the lower mantle. However, the resistance causes strong buckling and plastic thickening of these slabs, which accumulate to form huge blobs or 'megaliths' underneath the 660 km discontinuity. In contrast, slabs with seismic zones extending no deeper than 300 km possess much smaller degrees of negative buoyancy and strength and hence are unable to penetrate the 660 km discontinuity. Slabs of this type are recycled within the transition zone and upper mantle. Mixing and petrological homogenization processes are less efficient in the transition zone than in the upper mantle (above 400 km). The transition zone is composed mainly of ancient slabs

  13. The isolated 678-km deep 30 May 2015 MW 7.9 Ogasawara (Bonin) Islands earthquake

    NASA Astrophysics Data System (ADS)

    Ye, L.; Lay, T.; Zhan, Z.; Kanamori, H.; Hao, J.

    2015-12-01

    Deep-focus earthquakes, located 300 to 700 km below the Earth's surface within sinking slabs of relatively cold oceanic lithosphere, are mysterious phenomena. Seismic radiation from deep events is essentially indistinguishable from that for shallow stick-slip frictional-sliding earthquakes, but the confining pressure and temperature are so high for deep-focus events that a distinct process is likely needed to account for their abrupt energy release. The largest recorded deep-focus earthquake (MW 7.9) in the Izu-Bonin slab struck on 30 May 2015 beneath the Ogasawara (Bonin) Islands, isolated from prior seismicity by over 100 km in depth, and followed by only 2 small aftershocks. Globally, this is the deepest (678 km) major (MW > 7) earthquake in the seismological record. Seismicity indicates along-strike contortion of the Izu-Bonin slab, with horizontal flattening near a depth of 550 km in the Izu region and progressive steepening to near-vertical toward the south above the location of the 2015 event. Analyses of a large global data set of P, SH and pP seismic phases using short-period back-projection, subevent directivity, and broadband finite-fault inversion indicate that the mainshock ruptured a shallowly-dipping fault plane with patchy slip that spread over a distance of ~40 km with variable expansion rate (~5 km/s down-dip initially, ~3 km/s up-dip later). During the 17 s rupture duration the radiated energy was ~3.3 x 1016 J and the stress drop was ~38 MPa. The radiation efficiency is moderate (0.34), intermediate to that of the 1994 Bolivia and 2013 Sea of Okhotsk MW 8.3 earthquakes, indicating a continuum of processes. The isolated occurrence of the event suggests that localized stress concentration associated with the pronounced deformation of the Izu-Bonin slab likely played a role in generating this major earthquake.

  14. Polar Faculae Are Faculae Of Old Age, Ascending To Photosphere From Sun's Upper Magnetic Toroid Levels, And Then Descending Near Equator by 105 Km, In Their Circulatory Motion, To Depths Slightly Below That of Lower Magnetic Toroid, And Then Ascending Again To Photosphere At Lat. 0c ¡A~50¢ª, N. And S.KEITH L. MCDONALD, P. O. Box 2433, Salt Lake City, UT

    NASA Astrophysics Data System (ADS)

    McDonald, K. L.

    2004-11-01

    regions where they decay slowly owing to high electrical resistivity of neighboring gas, in absence of sustaining amplification and regenerative feedback mechanisms present in mag. toroids; always associated with passage of high speed stream, usu. supersonic, thru breach in toroid, an M-region, turbulence thus produces faculae. Waldmeir3 obs. mean diameter of polar faculae to be 2,300 km and lifetimes ranged from a few minutes to many days, which is our best evidence of extreme age. Details.4 1 McDonald, K. L., Solar-Terrestrial Electromagnetic Phenomena; ¢«¢«¢«, Bul. No. 145, Utah Engin. Expt. Sta., Univ. Utah, May 1984; 135 pp. 2 Sheeley, N. R., Jr., Ap. J., 140, No. 2, 731-735 (1964); J. Geophys. Res., 81 (19), 3462-4 (1976). 3 Waldmeir, M., ¡°Polar Fackeln¡±, Zs. F. Ap., 38, 37-54 (1955-56). 4 Kiepenheur, K. O., ¡°Solar Activity¡±, 322, in The Sun, ed. By G. P. Kuiper (Univ. Chicago Press, Ill., 1953).

  15. Spatial analysis of storm depths from an Arizona raingage network

    NASA Technical Reports Server (NTRS)

    Fennessey, N. M.; Eagleson, P. S.; Qinliang, W.; Rodriguez-Iturbe, I.

    1986-01-01

    Eight years of summer rainstorm observations are analyzed by a dense network of 93 raingages operated by the U.S. Department of Agriculture, Agricultural Research Service, in the 150 km Walnut Gulch experimental catchment near Tucson, Arizona. Storms are defined by the total depths collected at each raingage during the noon-to-noon period for which there was depth recorded at any of the gages. For each of the resulting 428 storm days, the gage depths are interpolated onto a dense grid and the resulting random field analyzed to obtain moments, isohyetal plots, spatial correlation function, variance function, and the spatial distribution of storm depth.

  16. Lectin KM+-induced neutrophil haptotaxis involves binding to laminin.

    PubMed

    Ganiko, Luciane; Martins, Antônio R; Freymüller, Edna; Mortara, Renato A; Roque-Barreira, Maria-Cristina

    2005-01-18

    The lectin KM+ from Artocarpus integrifolia, also known as artocarpin, induces neutrophil migration by haptotaxis. The interactions of KM+ with both the extracellular matrix (ECM) and neutrophils depend on the lectin ability to recognize mannose-containing glycans. Here, we report the binding of KM+ to laminin and demonstrate that this interaction potentiates the KM+-induced neutrophil migration. Labeling of lung tissue by KM+ located its ligands on the endothelial cells, in the basement membrane, in the alveolus, and in the interstitial connective tissue. Such labeling was inhibited by 400 mM D-mannose, 10 mM Manalpha1-3[Manalpha1-6]Man or 10 microM peroxidase (a glycoprotein-containing mannosyl heptasaccharide). Laminin is a tissue ligand for KM+, since both KM+ and anti-laminin antibodies not only reacted with the same high molecular mass components of a lung extract, but also determined colocalized labeling in basement membranes of the lung tissue. The relevance of the KM+-laminin interaction to the KM+ property of inducing neutrophil migration was evaluated. The inability of low concentrations of soluble KM+ to induce human neutrophil migration was reversed by coating the microchamber filter with laminin. So, the interaction of KM+ with laminin promotes the formation of a substrate-bound KM+ gradient that is able to induce neutrophil haptotaxis.

  17. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the companyused technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications.

  18. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the company used technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications

  19. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the company used technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications.

  20. Variable depth core sampler

    DOEpatents

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

    1996-02-20

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

  1. Variable depth core sampler

    DOEpatents

    Bourgeois, Peter M.; Reger, Robert J.

    1996-01-01

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

  2. Variable depth core sampler

    SciTech Connect

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

    1994-12-31

    This invention relates to a sampling means, more particularly to a device to sample hard surfaces at varying depths. Often it is desirable to take samples of a hard surface wherein the samples are of the same diameter but of varying depths. Current practice requires that a full top-to-bottom sample of the material be taken, using a hole saw, and boring a hole from one end of the material to the other. The sample thus taken is removed from the hole saw and the middle of said sample is then subjected to further investigation. This paper describes a variable depth core sampler comprimising a circular hole saw member, having longitudinal sections that collapse to form a point and capture a sample, and a second saw member residing inside the first hole saw member to support the longitudinal sections of the first member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside the the first hole saw member.

  3. Structural investigation of 5,10-A2B2-type porphyrins: palladium(II) and zinc(II) complexes of 5,10-dibromo-15,20-bis(4-methylphenyl)porphyrin.

    PubMed

    Senge, Mathias O; Zawadzka, Monika

    2014-12-01

    The analysis of [5,10-dibromo-15,20-bis(4-methylphenyl)porphyrinato]palladium(II), [Pd(C34H22Br2N4)], and [5,10-dibromo-15,20-bis(4-methylphenyl)porphyrinato](methanol)zinc(II), [Zn(C34H22Br2N4)(CH4O)], reveals a small but localized influence of the bromine residues on the conformation of the macrocycle. A comparison of the 5,10-dibromo substituent pattern with literature data for 5,15-dibromoporphyrins shows similar in-plane distortions in both but a different mix of out-of-plane distortion modes for the different regiochemical arrangements.

  4. Prestack depth migration applied to deep seismic data sets

    NASA Astrophysics Data System (ADS)

    Yoon, M.; Buske, S.; Lüth, S.; Shapiro, S.; Wigger, P.

    2003-04-01

    We present the results of Kirchhoff prestack depth migration applied to two onshore deep seismic reflection data sets (ANCORP'96 and PRECORP'95). The prestack depth migration was implemented in 3D (ANCORP) and in 2D (PRECORP), respectively, from topography. The 3D velocity model was obtained by extending a 2D velocity model received from refraction data analysis. The traveltime calculation was performed using a finite difference eikonal solver. An additional "offline stacking" provided a final 370 km long 2D depth section of the ANCORP data set. The migration procedure of the PRECORP data set consisted of three steps: First, early arrivals (0-15 s TWT) were processed. Second, later arrivals (15-40 s TWT) were passed to migration . Finally, both depth sections have been stacked and yielded the final 100 km deep subsurface image. In this paper a 180 km long part of the ANCORP section and a 110 km long PRECORP depth profile are presented. In comparison to earlier processing results (ANCORP working group, 1999; 2002) the prestack depth images contain new aspects. The final 2D ANCORP section shows a sharpened image of the oceanic crust. Except for some areas a nearly complete image of the Nazca reflector is present in both data sets between depths of 60 - 90 km. The compilation with local earthquake data shows that the seismogenic zone coincides with the upper reflector of the oceanic crust, but not with the Nazca reflector at depths larger than 80 km. The final depth sections contain two prominent features, the Quebrada Blanca Bright Spot (QBBS, ANCORP) and the Calama Bright Spot (CBS, PRECORP) located 160 km further to the south. Besides the west dip of the QBBS a 3D analysis of the ANCORP data set shows an additional north-dipping trend of the QBBS. Furthermore, the CBS is discovered for the first time. ANCORP Working Group (1999) Seismic reflection image revealing offset of Andean subduction-zone earthquake locations into oceanic mantle. Nature, 397:341--344. ANCORP

  5. Systematic variation in the depths of slabs beneath arc volcanoes

    USGS Publications Warehouse

    England, P.; Engdahl, R.; Thatcher, W.

    2004-01-01

    The depths to the tops of the zones of intermediate-depth seismicity beneath arc volcanoes are determined using the hypocentral locations of Engdahl et al. These depths are constant, to within a few kilometres, within individual arc segments, but differ by tens of kilometres from one arc segment to another. The range in depths is from 65 km to 130 km, inconsistent with the common belief that the volcanoes directly overlie the places where the slabs reach a critical depth that is roughly constant for all arcs. The depth to the top of the intermediate-depth seismicity beneath volcanoes correlates neither with age of the descending ocean floor nor with the thermal parameter of the slab. This depth does, however, exhibit an inverse correlation with the descent speed of the subducting plate, which is the controlling factor both for the thermal structure of the wedge of mantle above the slab and for the temperature at the top of the slab. We interpret this result as indicating that the location of arc volcanoes is controlled by a process that depends critically upon the temperature at the top of the slab, or in the wedge of mantle, immediately below the volcanic arc.

  6. Endotoxin in fine (PM 2.5) and coarse (PM 2.5-10) particle mass of ambient aerosols. A temporo-spatial analysis

    NASA Astrophysics Data System (ADS)

    Heinrich, Joachim; Pitz, Mike; Bischof, Wolfgang; Krug, Norbert; Borm, Paul J. A.

    Objectives: We collected fine (PM 2.5) and coarse (PM 2.5-10) particulate matter fractions in two areas ˜80 km apart and measured soluble endotoxin concentrations in both particle fractions. Here we report on temporo-spatial variation of endotoxin content in the collected particles. Methods: Dichotomous Anderson samplers were used to collect 21 weekly samples of PM 2.5 and PM 2.5-10 in both towns from January to June 2002. Each Teflon filter was water extracted and endotoxin was measured by a chromogenic Limulus Amoebocyte Lysate method. Endotoxin concentrations were expressed per mg of fine or mg of coarse mass and per sampled air volume (m 3). Results: For both cities, the mean endotoxin content in PM 2.5 was 1.2 EU mg -1; however the endotoxin content in the coarse fraction was ˜10 times higher compared to the fine mass fractions. Although endotoxin content is highly variable over time, a good correlation was observed between the two town sites for both fine ( r=0.85) and coarse PM ( r=0.88). The fluctuations of weekly endotoxin means were high in both areas suggesting a strong temporal dependence on particle source and composition. The endotoxin content in particles collected during May and June were two to four times higher than concentrations measured during the winter and early spring weeks. Conclusions: Ambient airborne endotoxin concentrations were detected in coarse and fine particle fraction, but 10-fold higher in the coarse PM. The strong seasonality and the week to week fluctuation of endotoxin content in PM indicate different biologic PM properties which might affect results of time series studies on short-term effects as well as in vitro studies and human exposure studies.

  7. Microphysical Model of the Venus clouds between 40km and 80km

    NASA Astrophysics Data System (ADS)

    McGouldrick, Kevin

    2013-10-01

    I am continuing to adapt the Community Aerosol and Radiation Model for Atmospheres (CARMA) to successfully simulate the multi-layered clouds of Venus. The present version of the one-dimensional model now includes a simple parameterization of the photochemicial production of sulfuric acid around altitudes of 62km, and its thermochemical destruction below cloud base. Photochemical production in the model is limited by the availability of water vapor and insolation. Upper cloud particles are introduced into the model via binary homogeneous nucleation, while the lower and middle cloud particles are created via activation of involatile cloud condensation nuclei. Growth by condensation and coagulation and coalescence are also treated. Mass loadings and particle sizes compare favorably with the in situ observations by the Pioneer Venus Large Probe Particle Size Spectrometer, and mixing ratios of volatiles compare favorably with remotely sensed observations of water vapor and sulfuric acid vapor. This work was supported by the NASA Planetary Atmospheres Program, grant number NNX11AD79G.

  8. Locking depths estimated from geodesy and seismology along the San Andreas Fault System: Implications for seismic moment release

    NASA Astrophysics Data System (ADS)

    Smith-Konter, Bridget R.; Sandwell, David T.; Shearer, Peter

    2011-06-01

    The depth of the seismogenic zone is a critical parameter for earthquake hazard models. Independent observations from seismology and geodesy can provide insight into the depths of faulting, but these depths do not always agree. Here we inspect variations in fault depths of 12 segments of the southern San Andreas Fault System derived from over 1000 GPS velocities and 66,000 relocated earthquake hypocenters. Geodetically determined locking depths range from 6 to 22 km, while seismogenic thicknesses are largely limited to depths of 11-20 km. These seismogenic depths best match the geodetic locking depths when estimated at the 95% cutoff depth in seismicity, and most fault segment depths agree to within 2 km. However, the Imperial, Coyote Creek, and Borrego segments have significant discrepancies. In these cases the geodetically inferred locking depths are much shallower than the seismogenic depths. We also examine variations in seismic moment accumulation rate per unit fault length as suggested by seismicity and geodesy and find that both approaches yield high rates (1.5-1.8 × 1013 Nm/yr/km) along the Mojave and Carrizo segments and low rates (˜0.2 × 1013 Nm/yr/km) along several San Jacinto segments. The largest difference in seismic moment between models is calculated for the Imperial segment, where the moment rate from seismic depths is a factor of ˜2.5 larger than that from geodetic depths. Such variability has important implications for the accuracy to which future major earthquake magnitudes can be estimated.

  9. Fault depth and seismic moment rate estimates of the San Andreas Fault System: Observations from seismology and geodesy

    NASA Astrophysics Data System (ADS)

    Smith-Konter, B. R.; Sandwell, D. T.; Shearer, P. M.

    2010-12-01

    The depth of the seismogenic zone is a critical parameter for earthquake hazard models of the San Andreas Fault System. Independent observations from both seismology and geodesy can provide insight into the depths of faulting, however these depths do not always agree. Here we inspect variations in fault depths of 12 segments of the southern San Andreas Fault System derived from over 1000 GPS velocities and 66,000 relocated earthquake hypocenters. Geodetically-determined locking depths range from 6-22 km, while seismogenic thicknesses are largely limited to depths of 11-20 km. Seismogenic depths best match the geodetic locking depths when estimated at the 95% cutoff depth in seismicity and most fault segment depths agree to within 2 km. However, we identify 3 outliers (Imperial, Coyote Creek, and Borrego segments) with significant discrepancies. In these cases the geodetically-inferred locking depths are much shallower than the seismogenic depths. We also inspect seismic moment accumulation rates per unit fault length, with the highest rates estimated for the Mojave and Carrizo segments (~1.8 x 1013 Nm/yr/km) and the lowest rates (~0.2 x 1013 Nm/yr/km) found along several San Jacinto segments. The largest variation in seismic moment is calculated for the Imperial segment, where the moment rate from seismic depths is nearly a factor of 2.5 larger than that from geodetic depths. Such variability has important implications for the accuracy to which the magnitude of future major earthquakes can be estimated.

  10. The thermal influence of the subducting slab beneath South America from 410 and 660 km discontinuity observations

    NASA Astrophysics Data System (ADS)

    Collier, J. D.; Helffrich, G. R.

    2001-11-01

    Regional seismic network data from deep South American earthquakes to western United States and western European seismic arrays is slant stacked to detect weak near-source interactions with upper mantle discontinuities. These observations are complemented by an analysis of earlier work by Sacks & Snoke (1977) who observed S to P conversions from deep events to stations in South America, and similar observations from 1994-95 events using the BANJO and SEDA networks. Observations of the depth of the 410km discontinuity are made beneath central South America in the vicinity of the aseismic region of the subducting Nazca Plate. These results image the 410km discontinuity over a lateral extent of up to 850km perpendicular to the slab and over a distance of 2700km along the length of the slab. Away from the subducting slab the discontinuity is mainly seen near its global average depth, whilst inside the slab there is evidence for its elevation by up to around 60km but with significant scatter in the data. These results are consistent with the presence of a continuous slab through the aseismic region with a thermal anomaly of 900°C at 350km depth. This value is in good agreement with simple thermal models though our data are too sparse to accurately constrain them. Sparse observations of the 660km discontinuity agree with tomographic models suggesting penetration of the lower mantle by the slab in the north but stagnation at the base of the transition zone in the south. The geographical distribution of the data, however, does not allow us to rule out the possibility of slab stagnation at the base of the transition zone in the north. These observations, together with the presence of deep earthquakes, require more complicated thermal models than previously used to explain them, possibly including changes in slab dip and age with depth.

  11. Efficient multiview depth video coding using depth synthesis prediction

    NASA Astrophysics Data System (ADS)

    Lee, Cheon; Choi, Byeongho; Ho, Yo-Sung

    2011-07-01

    The view synthesis prediction (VSP) method utilizes interview correlations between views by generating an additional reference frame in the multiview video coding. This paper describes a multiview depth video coding scheme that incorporates depth view synthesis and additional prediction modes. In the proposed scheme, we exploit the reconstructed neighboring depth frame to generate an additional reference depth image for the current viewpoint to be coded using the depth image-based-rendering technique. In order to generate high-quality reference depth images, we used pre-processing on depth, depth image warping, and two types of hole filling methods depending on the number of available reference views. After synthesizing the additional depth image, we encode the depth video using the proposed additional prediction modes named VSP modes; those additional modes refer to the synthesized depth image. In particular, the VSP_SKIP mode refers to the co-located block of the synthesized frame without the coding motion vectors and residual data, which gives most of the coding gains. Experimental results demonstrate that the proposed depth view synthesis method provides high-quality depth images for the current view and the proposed VSP modes provide high coding gains, especially on the anchor frames.

  12. Synthesis and anti-tubercular activity of N(2)-arylbenzo[g]isoquinoline-5,10-dione-3-iminium bromides.

    PubMed

    Rotthier, G; Cappoen, D; Nguyen, Quang Trung; Dang Thi, Tuyet Anh; Mathys, V; Nguyen, Van Tuyen; Huygen, K; Maes, L; Cos, P; Abbaspour Tehrani, K

    2016-02-14

    Tuberculosis has remained a challenge for medicinal chemists worldwide. In the framework of a collaborative program to identify and evaluate novel antitubercular candidate compounds, the biological properties of benzo[g]isoquinoline-5,10-diones have been found to be very promising. In this paper we have further expanded the library by incorporation of an amidinium moiety into the benzo[g]isoquinoline-5,10-dione scaffold. The presence of this functional group also increased the solubility of the quinones in polar solvents. To this purpose N(2)-arylbenzo[g]isoquinoline-5,10-dione-3-iminium bromides were synthesized in a straightforward way by means of a reaction of anilines with 2-(bromomethyl)-3-(cyanomethyl)-1,4-dimethoxynaphthalene. Following the biological evaluation, N(2)-(4-chlorophenyl)-5,10-dioxobenzo[g]isoquinoline-3(2H)-iminium bromide (MIC = 1.16 μM, CC50 = 28.51 μM, SI = 24.58) was selected as the most promising representative. Apart from the nano-molar anti-mycobacterial activity, the compound was able to target intracellular residing Mycobacterium tuberculosis and the susceptibility of a multi-drug-resistant strain towards the compound was confirmed.

  13. Low-velocity zone atop the 410-km seismic discontinuity in the northwestern United States.

    PubMed

    Song, Teh-Ru Alex; Helmberger, Don V; Grand, Stephen P

    2004-02-01

    The seismic discontinuity at 410 km depth in the Earth's mantle is generally attributed to the phase transition of (Mg,Fe)2SiO4 (refs 1, 2) from the olivine to wadsleyite structure. Variation in the depth of this discontinuity is often taken as a proxy for mantle temperature owing to its response to thermal perturbations. For example, a cold anomaly would elevate the 410-km discontinuity, because of its positive Clapeyron slope, whereas a warm anomaly would depress the discontinuity. But trade-offs between seismic wave-speed heterogeneity and discontinuity topography often inhibit detailed analysis of these discontinuities, and structure often appears very complicated. Here we simultaneously model seismic refracted waves and scattered waves from the 410-km discontinuity in the western United States to constrain structure in the region. We find a low-velocity zone, with a shear-wave velocity drop of 5%, on top of the 410-km discontinuity beneath the northwestern United States, extending from southwestern Oregon to the northern Basin and Range province. This low-velocity zone has a thickness that varies from 20 to 90 km with rapid lateral variations. Its spatial extent coincides with both an anomalous composition of overlying volcanism and seismic 'receiver-function' observations observed above the region. We interpret the low-velocity zone as a compositional anomaly, possibly due to a dense partial-melt layer, which may be linked to prior subduction of the Farallon plate and back-arc extension. The existence of such a layer could be indicative of high water content in the Earth's transition zone.

  14. Depth of conduit flow in unconfined carbonate aquifers

    NASA Astrophysics Data System (ADS)

    Worthington, Stephen R. H.

    2001-04-01

    The locus of formation of cave conduits in carbonate aquifers is dependent on hydraulic, structural, and solubility factors, and these can facilitate flow deep below the water table. Geothermal heating results in increasing temperatures and decreasing viscosity with depth. This favors deep conduit development for flow paths with lengths >3 km. Steeply dipping strata aid the flow of undersaturated water to depth along bedding planes. These factors indicate that flow deep below the water table should be associated with steep dips and long flow paths. Empirical evidence strongly supports this model and demonstrates that the flow depth of conduits is directly proportional to flow-path length and stratal dip.

  15. Exploring the Benefits of KM Education for LIS Professionals

    ERIC Educational Resources Information Center

    Hazeri, Afsaneh; Martin, Bill; Sarrafzadeh, Maryam

    2009-01-01

    It is to be expected that in a new and emerging discipline like knowledge management (KM) there still will be ambivalence among both LIS educational institutions and their students, as to the need to have KM courses. Investigating the benefits of engaging with these programs might help to clear up this ambiguity. The present paper seeks to shed…

  16. 7 CFR 29.1035 - Mixed color (KM).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Mixed color (KM). 29.1035 Section 29.1035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1035 Mixed color (KM). Distinctly different colors of the type mingled together....

  17. 7 CFR 29.1035 - Mixed color (KM).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Mixed color (KM). 29.1035 Section 29.1035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1035 Mixed color (KM). Distinctly different colors of the type mingled together....

  18. 7 CFR 29.1035 - Mixed color (KM).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Mixed color (KM). 29.1035 Section 29.1035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1035 Mixed color (KM). Distinctly different colors of the type mingled together....

  19. 7 CFR 29.1035 - Mixed color (KM).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Mixed color (KM). 29.1035 Section 29.1035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1035 Mixed color (KM). Distinctly different colors of the type mingled together....

  20. 7 CFR 29.1035 - Mixed color (KM).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Mixed color (KM). 29.1035 Section 29.1035 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1035 Mixed color (KM). Distinctly different colors of the type mingled together....

  1. Moho Depth of the Yakutat Terrane, Southern Alaska

    NASA Astrophysics Data System (ADS)

    Christeson, G. L.; Van Avendonk, H. J.; Gulick, S. P.; Pavlis, G. L.; Hansen, R. A.

    2011-12-01

    The Yakutat terrane, a thickened oceanic plateau, is currently colliding with southern Alaska forming the Chugach-St. Elias orogen. Two-dimensional marine seismic profiles acquired during the STEEP project map the Moho of the terrane at a constant depth of 30-32 km over a distance >300 km from the Bering Glacier east to the Dangerous River Zone, and over a distance of >100 km from the Transition fault north towards Yakutat Bay. However, Moho depth of the terrane is poorly constrained to the north beneath the Chugach-St. Elias mountains. Fortunately, good Moho reflections are observed by land-based seismometers recording the marine shots of the STEEP project over source-receiver offsets up to 200 km. We will use these data to invert for Yakutat terrane Moho depth. We will first use all first-arriving energy to do a three-dimensional tomographic inversion for crustal velocity structure, and then will invert all interpreted Moho reflections for Moho depth. The results should give us new insights into the tectonic processes associated with the Chugach-St. Elias orogen.

  2. Exploring KM Features of High-Performance Companies

    NASA Astrophysics Data System (ADS)

    Wu, Wei-Wen

    2007-12-01

    For reacting to an increasingly rival business environment, many companies emphasize the importance of knowledge management (KM). It is a favorable way to explore and learn KM features of high-performance companies. However, finding out the critical KM features of high-performance companies is a qualitative analysis problem. To handle this kind of problem, the rough set approach is suitable because it is based on data-mining techniques to discover knowledge without rigorous statistical assumptions. Thus, this paper explored KM features of high-performance companies by using the rough set approach. The results show that high-performance companies stress the importance on both tacit and explicit knowledge, and consider that incentives and evaluations are the essentials to implementing KM.

  3. Natural fracturing, by depth

    NASA Astrophysics Data System (ADS)

    Hooker, John; Laubach, Stephen

    2013-04-01

    Natural opening-mode fractures commonly fall upon a spectrum whose end-members are veins, which have wide ranges of sizes and are mostly or thoroughly cemented, and joints, which have little opening displacement and little or no cement. The vein end-member is common in metamorphic rocks, whose high temperature and pressure of formation place them outside typical reservoir settings; conversely, many uncemented joints likely form near the surface and so too have limited relevance to subsurface exploration. Sampling of cores retrieved from tight-gas sandstone reservoirs suggest that it is intermediate fractures, not true joints or veins, that provide natural porosity and permeability. Such fractures have abundant pore space among fracture-bridging cements, which may hold fractures open despite varying states of stress through time. Thus the more sophisticated our understanding of the processes that form veins and joints, i.e., how natural fracturing varies by depth, the better our ability to predict intermediate fractures. Systematic differences between veins and joints, in terms of size-scaling and lateral and stratigraphic spatial arrangement, have been explained in the literature by the mechanical effects of sedimentary layering, which likely exert more control over fracture patterns at shallower depths. Thus stratabound joints commonly have narrow size ranges and regular spacing; non-stratabound veins have a wide range of sizes and spacings. However, new fieldwork and careful literature review suggest that the effects of mechanical layering are only half the story. Although atypical, veins may be highly stratabound and yet spatially clustered; non-stratabound fractures may nonetheless feature narrow size ranges. These anomalous fracture arrangements are better explained by the presence of precipitating cements during fracture opening than by mechanical layering. Cement is thought to be highly important for fracture permeability, but potential effects of

  4. Variations in effective compensation depth across Aphrodite Terra, Venus

    SciTech Connect

    Herrick, R.R.; Hall, S.A. ); Bills, B.G.

    1989-06-01

    Aphrodite Terra is the largest elevated terrain on Venus and it serves as a focal point in current discussions of global tectonic style. Using the topography and gravity data acquired by the Pioneer Venus Orbiter (PVO) the authors have estimated an effective depth of Airy compensation for each of 75 orbital arcs that provide fairly uniform areal coverage of the entire province. The most pronounced pattern that emerges is a general increase in compensation depth to the east. The most rapid change occurs near 135{degree}; the average west of there is 70 km, while the average to the east is 230 km. Superimposed on this larger trend are five distinctive regional patterns, four well defined peaks and one interval of widely scattered and poorly constrained depths. The maxima in compensation depth are well correlated with regional topographic highs. While these observations are easily reconciled with the general notion that Aphrodite is a region of crustal divergence, the great depth of compensation is difficult to accord with the more specific suggestion that Aphrodite is a terrestrial type divergent plate margin. The alternative suggestion that Aphrodite, and the other equatorial highlands on Venus, are surface manifestations of hot upwelling mantle plumes is consistent both with the great depths of compensation and with the pattern of regional peaks and intervening troughs. The broader scale increase in effective depth of compensation from west to east is more enigmatic, but it might reflect an age progression of the plumes.

  5. Marshall Space Flight Center Propulsion Systems Department (PSD) KM Initiative

    NASA Technical Reports Server (NTRS)

    Caraccioli, Paul; Varnadoe, Tom; McCarter, Mike

    2006-01-01

    NASA Marshall Space Flight Center s Propulsion Systems Department (PSD) is four months into a fifteen month Knowledge Management (KM) initiative to support enhanced engineering decision making and analyses, faster resolution of anomalies (near-term) and effective, efficient knowledge infused engineering processes, reduced knowledge attrition, and reduced anomaly occurrences (long-term). The near-term objective of this initiative is developing a KM Pilot project, within the context of a 3-5 year KM strategy, to introduce and evaluate the use of KM within PSD. An internal NASA/MSFC PSD KM team was established early in project formulation to maintain a practitioner, user-centric focus throughout the conceptual development, planning and deployment of KM technologies and capabilities with in the PSD. The PSD internal team is supported by the University of Alabama's Aging Infrastructure Systems Center Of Excellence (AISCE), Intergraph Corporation, and The Knowledge Institute. The principle product of the initial four month effort has been strategic planning of PSD KM implementation by first determining the "as is" state of KM capabilities and developing, planning and documenting the roadmap to achieve the desired "to be" state. Activities undertaken to support the planning phase have included data gathering; cultural surveys, group work-sessions, interviews, documentation review, and independent research. Assessments and analyses have been performed including industry benchmarking, related local and Agency initiatives, specific tools and techniques used and strategies for leveraging existing resources, people and technology to achieve common KM goals. Key findings captured in the PSD KM Strategic Plan include the system vision, purpose, stakeholders, prioritized strategic objectives mapped to the top ten practitioner needs and analysis of current resource usage. Opportunities identified from research, analyses, cultural/KM surveys and practitioner interviews include

  6. Mapping the earth conductivity-depth structure of African geomagnetic equatorial anomaly regions using solar quiet current variations

    NASA Astrophysics Data System (ADS)

    Ugbor, D. O.; Okeke, F. N.; Yumoto, K.

    2016-04-01

    The solar quiet day ionospheric (Sq) current variations observed in Abuja, Bangui and Addis Ababa were used to delineate the mantle conductivity-depth structure along the equatorial African regions. Spherical harmonic analysis (SHA) was employed in separating the internal and external field contributions to the Sq variations. For each of the paired external and internal coefficients of the SHA, we used transfer function to compute the conductivity-depth profile for the region. Strikingly, we observed increased electrical conductivity values in the Earth layers and deep depth penetration. The calculated average electrical conductivity values in Addis Ababa and Abuja are 0.087 Sm-1 and 0.104 Sm-1 at depths of 93 km and 121 km respectively. These values suddenly rose to 0.235 Sm-1 and 0.222 Sm-1 at depths of 440 km and 427 km respectively. In Bangui, the calculated average values are 0.092 Sm-1, 0.144 Sm-1, 0.312 Sm-1 and 0.466 Sm-1 at 96 km, 300 km, 834 km and 1228 km depths respectively. At the greatest depths of penetration of 1412 km, 1385 km and 1278 km in Addis Ababa, Abuja and Bangui, the electrical conductivity attained the highest values of 0.415 Sm-1, 0.467 Sm-1 and 0.515 Sm-1 respectively. Two most Earth conductive layers were discovered in the magnetic equatorial zone. These layers lie between the depth of about 100 and 400 km within the upper mantle and beyond 1200 km in the lower mantle. It can be inferred that the closer one goes towards the Earth magnetic equator; the deeper the Sq current can penetrate the Earth's interior.

  7. The KM phase in semi-realistic heterotic orbifold models

    SciTech Connect

    Giedt, Joel

    2000-07-05

    In string-inspired semi-realistic heterotic orbifolds models with an anomalous U(1){sub X},a nonzero Kobayashi-Masakawa (KM) phase is shown to arise generically from the expectation values of complex scalar fields, which appear in nonrenormalizable quark mass couplings. Modular covariant nonrenormalizable superpotential couplings are constructed. A toy Z{sub 3} orbifold model is analyzed in some detail. Modular symmetries and orbifold selection rules are taken into account and do not lead to a cancellation of the KM phase. We also discuss attempts to obtain the KM phase solely from renormalizable interactions.

  8. Topography of the 660-km seismic discontinuity beneath Izu-Bonin: Implications for tectonic history and slab deformation

    NASA Astrophysics Data System (ADS)

    Castle, John C.; Creager, Kenneth C.

    1998-06-01

    We analyze the P wave codas of 65 paths from deep northwestern Pacific earthquakes recorded by arrays of stations in Germany, the western United States, India, and Turkmenistan. We identify a phase resulting from a near-source S-to-P conversion at a nearly horizontal discontinuity ranging in depth from 650 to 730 km, which we interpret as a thermally depressed spinel to perovskite and magnesiowüstite phase transition. We migrate these data along with 39 more from Wicks and Richards [1993], accounting for three-dimensional ray bending by the sloping discontinuity, to produce a high-resolution topography map of the 660-km discontinuity in the Izu-Bonin region. Assuming an equilibrium phase transition, we interpret the discontinuity depth in terms of local temperatures. The slab, if defined by a thermal anomaly greater than -400°K, is only about 100 km thick near 28°N suggesting the slab is penetrating into the lower mantle with little or no advective thickening. Farther to the north, however, cold material appears spread out over a wide region, consistent with the slab having been laid down flat on the 660-km discontinuity as the trench retreated 2000 km eastward. Both the narrow slab to the south and the flat-lying slab to the north are consistent with recent high-resolution tomographic images. The depression to 745 km along the arc is consistent with a maximum thermal anomaly of about 1100°K. Along the entire arc, the depression occurs directly beneath the deepest earthquakes, even where seismicity is dipping at 45° and stops at 450 km depth, suggesting that the slab steepens to a vertical dip at the deepest seismicity. This change to a vertical orientation suggests that the slab loses strength temporarily through a physical process which causes the seismicity to increase dramatically and then abruptly cease.

  9. On Physical Nature of the 70-km Seismic Boundary Caused by Tidal and Fluid Effects.

    NASA Astrophysics Data System (ADS)

    Elena, S.; Boris, L.; Michail, R.

    2007-12-01

    Statistic analysis of the EQ catalogs (ISC, NEIC, 1960-2006; Harward Catalog, 1976-2005) showed that the seismic boundary at the 70-km depth marked out often as a real boundary, which divides all events into two separate classes: non-deep seismic events (about 85% of all events) which respond to external perturbation effects, and the deep-focus events non-responded to an outer influence. The results of two series of statistical analyses were presented. All events were subdivided into two groups: shallow events (H<=Htr) and deep events (H>Htr), where Htr is threshold value of the EQ source depth. The statistical verification of hypothesis about within-year variability existence for the events of various energy levels [Sasorova, Zhuravlev, 2006] was carried out in the first series. It was disproved the null hypothesis about uniform EQ distributions in the course of year for shallow events. But it was confirmed the null hypothesis for deep EQ. The statistical verification of hypothesis about existence non-random component in time distribution of the EQ's between the northern and southern part of the Pacific [Sasorova et al, 2006] was carried out in the second series. It was found (according the distribution-free test) that nonrandom component does not exist for deep EQs. But it is clearly manifested in time distribution of the shallow events. In both cases it was found that the Htr boundary between the shallow and the deep events was arranged at the depth between 60 and 80 km (we let to vary Htr value from 15 to 300 km). Thus the EQ with sources located above this boundary are affected by external factors, which may trigger the process of EQ generation, while the external factors don't influence on the EQ sources located below this boundary. The drastic change of EQ source parameter values via hypocenter depth was also observed near the 70-km depth boundary [Rodkin, 2004]. Revealed parameter change is connecting with difference in the deep fluid behavior. The equation

  10. Testing the depth-differentiation hypothesis in a deepwater octocoral.

    PubMed

    Quattrini, Andrea M; Baums, Iliana B; Shank, Timothy M; Morrison, Cheryl L; Cordes, Erik E

    2015-05-22

    The depth-differentiation hypothesis proposes that the bathyal region is a source of genetic diversity and an area where there is a high rate of species formation. Genetic differentiation should thus occur over relatively small vertical distances, particularly along the upper continental slope (200-1000 m) where oceanography varies greatly over small differences in depth. To test whether genetic differentiation within deepwater octocorals is greater over vertical rather than geographical distances, Callogorgia delta was targeted. This species commonly occurs throughout the northern Gulf of Mexico at depths ranging from 400 to 900 m. We found significant genetic differentiation (FST = 0.042) across seven sites spanning 400 km of distance and 400 m of depth. A pattern of isolation by depth emerged, but geographical distance between sites may further limit gene flow. Water mass boundaries may serve to isolate populations across depth; however, adaptive divergence with depth is also a possible scenario. Microsatellite markers also revealed significant genetic differentiation (FST = 0.434) between C. delta and a closely related species, Callogorgia americana, demonstrating the utility of microsatellites in species delimitation of octocorals. Results provided support for the depth-differentiation hypothesis, strengthening the notion that factors covarying with depth serve as isolation mechanisms in deep-sea populations.

  11. Testing the depth-differentiation hypothesis in a deepwater octocoral.

    PubMed

    Quattrini, Andrea M; Baums, Iliana B; Shank, Timothy M; Morrison, Cheryl L; Cordes, Erik E

    2015-05-22

    The depth-differentiation hypothesis proposes that the bathyal region is a source of genetic diversity and an area where there is a high rate of species formation. Genetic differentiation should thus occur over relatively small vertical distances, particularly along the upper continental slope (200-1000 m) where oceanography varies greatly over small differences in depth. To test whether genetic differentiation within deepwater octocorals is greater over vertical rather than geographical distances, Callogorgia delta was targeted. This species commonly occurs throughout the northern Gulf of Mexico at depths ranging from 400 to 900 m. We found significant genetic differentiation (FST = 0.042) across seven sites spanning 400 km of distance and 400 m of depth. A pattern of isolation by depth emerged, but geographical distance between sites may further limit gene flow. Water mass boundaries may serve to isolate populations across depth; however, adaptive divergence with depth is also a possible scenario. Microsatellite markers also revealed significant genetic differentiation (FST = 0.434) between C. delta and a closely related species, Callogorgia americana, demonstrating the utility of microsatellites in species delimitation of octocorals. Results provided support for the depth-differentiation hypothesis, strengthening the notion that factors covarying with depth serve as isolation mechanisms in deep-sea populations. PMID:25904664

  12. Testing the depth-differentiation hypothesis in a deepwater octocoral

    PubMed Central

    Quattrini, Andrea M.; Baums, Iliana B.; Shank, Timothy M.; Morrison, Cheryl L.; Cordes, Erik E.

    2015-01-01

    The depth-differentiation hypothesis proposes that the bathyal region is a source of genetic diversity and an area where there is a high rate of species formation. Genetic differentiation should thus occur over relatively small vertical distances, particularly along the upper continental slope (200–1000 m) where oceanography varies greatly over small differences in depth. To test whether genetic differentiation within deepwater octocorals is greater over vertical rather than geographical distances, Callogorgia delta was targeted. This species commonly occurs throughout the northern Gulf of Mexico at depths ranging from 400 to 900 m. We found significant genetic differentiation (FST = 0.042) across seven sites spanning 400 km of distance and 400 m of depth. A pattern of isolation by depth emerged, but geographical distance between sites may further limit gene flow. Water mass boundaries may serve to isolate populations across depth; however, adaptive divergence with depth is also a possible scenario. Microsatellite markers also revealed significant genetic differentiation (FST = 0.434) between C. delta and a closely related species, Callogorgia americana, demonstrating the utility of microsatellites in species delimitation of octocorals. Results provided support for the depth-differentiation hypothesis, strengthening the notion that factors covarying with depth serve as isolation mechanisms in deep-sea populations. PMID:25904664

  13. HUBBLE FRONTIER FIELDS FIRST COMPLETE CLUSTER DATA: FAINT GALAXIES AT z ∼ 5-10 FOR UV LUMINOSITY FUNCTIONS AND COSMIC REIONIZATION

    SciTech Connect

    Ishigaki, Masafumi; Ouchi, Masami; Ono, Yoshiaki; Kawamata, Ryota; Shimasaku, Kazuhiro; Oguri, Masamune

    2015-01-20

    We present comprehensive analyses of faint dropout galaxies up to z ∼ 10 with the first full-depth data set of the A2744 lensing cluster and parallel fields observed by the Hubble Frontier Fields (HFF) program. We identify 54 dropouts at z ∼ 5-10 in the HFF fields and enlarge the size of the z ∼ 9 galaxy sample obtained to date. Although the number of highly magnified (μ ∼ 10) galaxies is small because of the tiny survey volume of strong lensing, our study reaches the galaxies' intrinsic luminosities comparable to the deepest-field HUDF studies. We derive UV luminosity functions with these faint dropouts, carefully evaluating by intensive simulations the combination of observational incompleteness and lensing effects in the image plane, including magnification, distortion, and multiplication of images, with the evaluation of mass model dependencies. Our results confirm that the faint-end slope, α, is as steep as –2 at z ∼ 6-8 and strengthen the evidence for the rapid decrease of UV luminosity densities, ρ{sub UV}, at z > 8 from the large z ∼ 9 sample. We examine whether the rapid ρ{sub UV} decrease trend can be reconciled with the large Thomson scattering optical depth, τ{sub e}, measured by cosmic microwave background experiments, allowing a large space of free parameters, such as an average ionizing photon escape fraction and a stellar-population-dependent conversion factor. No parameter set can reproduce both the rapid ρ{sub UV} decrease and the large τ {sub e}. It is possible that the ρ{sub UV} decrease moderates at z ≳ 11, that the free parameters significantly evolve toward high z, or that there exist additional sources of reionization such as X-ray binaries and faint active galactic nuclei.

  14. Taxonomic characterization and metabolic analysis of the Halomonas sp. KM-1, a highly bioplastic poly(3-hydroxybutyrate)-producing bacterium.

    PubMed

    Kawata, Yoshikazu; Shi, Lian-Hua; Kawasaki, Kazunori; Shigeri, Yasushi

    2012-04-01

    In a brief previous report, the gram-negative moderately halophilic bacterium, Halomonas sp. KM-1, that was isolated in our laboratory was shown to produce the bioplastic, poly(3-hydroxybutyrate) (PHB), using biodiesel waste glycerol (Kawata and Aiba, Biosci. Biotechnol. Biochem., 74, 175-177, 2010). Here, we further characterized this KM-1 strain and compared it to other Halomonas strains. Strain KM-1 was subjected to a polyphasic taxonomic study. Strain KM-1 was rod-shaped and formed colonies on a plate that were cream-beige in color, smooth, opaque, and circular with entire edges. KM-1 grew under environmental conditions of 0.1%-10% (w/v) NaCl, pH 6.5-10.5 and at temperatures between 10°C and 45°C. The G+C content of strain KM-1 was 63.9 mol%. Of the 16 Halomonas strains examined in this study, the strain KM-1 exhibited the highest production of PHB (63.6%, w/v) in SOT medium supplemented with 10% glycerol, 10.0 g/L sodium nitrate and 2.0 g/L dipotassium hydrogen phosphate. The intracellular structures within which PHB accumulated had the appearance of intracellular granules with a diameter of approximately 0.5 μm, as assessed by electron microscopy. The intra- and extra-cellular metabolites of strain KM-1 were analyzed by capillary electrophoresis mass spectrometry. In spite of the high amount of PHB stored intra-cellularly, as possible precursors for PHB only a small quantity of 3-hydroxybutyric acid and acetyl CoA, and no quantity of 3-hydroxybutyl CoA, acetoacetyl CoA and acetoacetate were detected either intra- or extra-cellularly, suggesting highly efficient conversion of these precursors to PHB.

  15. Weekly cycle of magnetic characteristics of PM2.5 and PM2.5-10 in Beijing, China

    NASA Astrophysics Data System (ADS)

    SHI, M.; Wu, H.; Zhang, S.; Li, H.; Yang, T.

    2013-12-01

    In urban areas,fine particle matter with aerodynamic diameter between 2.5 um and 10 um (PM2.5-10), and 2.5 um (PM2.5), as an important source of urban particulate matter (PM) pollutants, have significant negative effects on health, atmospheric visibility and climate. PM has increasingly become a significant index of indicating the atmospheric pollution of city. In recent years, Beijing, China has been listed as one of the most serious air pollution city in the world. In order to investigate the sources of air pollutants, a total of 283 pairs of PM2.5 and PM2.5-10 samples were collected daily from July, 2010 to June, 2011 in Beijing. Mineral magnetic properties and Scanning electron microscope (SEM) observations and energy dispersive X-ray spectroscopy (EDS) analyses of PM2.5 and PM2.5-10 were measured to verify the magnetic materials. Magnetic measures for PM indicated that the major magnetic phase was coarse-grained magnetite-like material. The χlf, χarm, SIRM and χarm/SIRM series of the PM2.5 and PM2.5-10 show seasonal dependences: high values in winter and low values in summer. In additional the parameters analyzed by Time-series methods show a strong cycle about 7 days above 95% confidence level. Weekly cycle of magnetic characteristics of PM2.5 and PM2.5-10 show different pattern: the concentration of magnetic particles in PM2.5-10 show high values in mid-week, and particle sizes is steady, while the concentration of magnetic particles in PM2.5 show reverse a weekly cycle pattern, and particle sizes is smaller in the mid-week.Microscopy analyses reveal basically three morphologies of magnetic grains: aggregate, spherules and angular particles. The ultrafine carbonaceous particles which tend to form complex clusters and chain-like structures, most likely come from coal burning and motor vehicle exhaust. Spherical particles in PM2.5 are dominantly composed of Fe, O and C, grain-diameters of particles range from 0.3 to 2 um. Angular particles of Fe

  16. The design of the optical modules of the KM3NeT-Italia project towers

    NASA Astrophysics Data System (ADS)

    Leonora, Emanuele; Aiello, Sebastiano; Giordano, Valentina

    2016-07-01

    The KM3NeT-Italia project aims to construct a large volume underwater neutrino telescope, to be installed in the depths of the Mediterranean Sea. The R&D and mass production phases of the detection elements of the telescope, the optical modules, were entirely performed in the INFN-LNS site in the harbour of Catania. In November 2014 a first tower of 14 storeys equipped with 84 optical modules was successfully deployed in the Mediterranean Sea site. The design of the optical modules and their main components are described in this paper.

  17. The -145 km/s Absorption System of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, Theodore R.; Danks, A.; Johansson, S.

    2002-01-01

    With the STIS E230H mode (R approx. 118,000), we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 km/s, are quite different in character from the others, mostly at intermediate velocities. The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000/cm, well above the 2000/cm noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes. Observations were accomplished through STScI under proposal 9242. Funding is through the STIS GTO resources.

  18. 4-km body(ies?) embedded in Saturn's Huygens Ringlet

    NASA Astrophysics Data System (ADS)

    Spitale, Joseph N.; Hahn, Joseph M.; Tamayo, Daniel

    2016-05-01

    Saturn's 20-km-wide Huygens ringlet, located ~250 km exterior to the B ring, displays unusual kinematics, as evidenced by a time variable width-relation. The cause of this behavior is not clear, but may be related to the presence of large embedded bodies (Spitale and Hahn 2016). The largest such bodies produce half-propeller-shaped disturbances originating at the inner edge of the ringlet, whose radial widths imply a size of ~4 km, based on simple scaling from A-ring propellers. Here, we show that a numerical N-body model of the ringlet with a 4-km body embedded near the inner edge produces features that are consistent with the observed half propellers.

  19. High energy neutrino detection with KM3NeT

    NASA Astrophysics Data System (ADS)

    Migliozzi, Pasquale; KM3NeT Collaboration

    2016-05-01

    The KM3NeT Collaboration has started the construction of a next generation high-energy neutrino telescope in the Mediterranean Sea: the largest and most sensitive neutrino research infrastructure. The full KM3NeT detector will be a several cubic kilometres distributed, networked infrastructure. In Italy, off the coast of Capo Passero, and in France, off the coast of Toulon. Thanks to its location in the Northern hemisphere and to its large instrumented volume, KM3NeT will be the optimal instrument to search for neutrinos from the Southern sky and in particular from the Galactic plane, thus making it complementary to IceCube. In this work the technologically innovative component of the detector, the status of construction and the first results from prototypes of the KM3NeT detector will be described as well as its capability to discover neutrino sources are reported.

  20. Akeno 20 km (2) air shower array (Akeno Branch)

    NASA Technical Reports Server (NTRS)

    Teshima, M.; Ohoka, H.; Matsubara, Y.; Hara, T.; Hatano, Y.; Hayashida, N.; He, C. X.; Honda, M.; Ishikawa, F.; Kamata, K.

    1985-01-01

    As the first stage of the future huge array, the Akeno air shower array was expanded to about 20 sq. km. by adding 19 scintillation detectors of 2.25 sq m area outside the present 1 sq. km. Akeno array with a new data collection system. These detectors are spaced about 1km from each other and connected by two optical fiber cables. This array has been in partial operation from 8th, Sep. 1984 and full operation from 20th, Dec. 1984. 20 sq m muon stations are planned to be set with 2km separation and one of them is now under construction. The origin of the highest energy cosmic rays is studied.

  1. Prestack depth migration for 3D offshore methane hydrates data

    NASA Astrophysics Data System (ADS)

    Jang, Seonghyung; Kim, Tae-yeon

    2015-04-01

    One of the indicators for the existence of methane hydrates on seismic data is BSR (bottom simulated reflector), which shows the base of the gas hydrate stability zone. It shows a reversed phase polarity compared to that of the water bottom reflections and high amplitude reflections. It is well known acoustic velocity decrease at the contact between gas hydrates and free-gas-bearing sediments. Prestack reverse time migration (RTM) is a method for imaging the subsurface in depth domain using inner product of source wavefield extrapolation in forward and receiver wavefield extrapolation in backward. It is widely used for imaging the complex subsurface structures with keeping amplitude. We applied RTM to 3D offshore seismic data for methane hydrates exploration. The study area is 12 x 25 km with 120 survey lines offshore. The shot gathers were acquired with 2 streamers and each one has 240 channels. Shot and receiver spacing is 25 m and 12.5 m. The line spacing is 100 m. Near offset is 150 m and maximum far offset is 3137.5 m. The record length is 7 second with a sampling rate of 1 ms. Shot gathers after resampled with 4 ms were processed to enhance signal to noise ratio using conventional basic processing such as amplitude recovery, deconvolution, and band-pass filtering. Interval velocities which were calculated from conventional stack velocities were used for velocity model for RTM. The basic-processed shot gathers and a velocity model were used for input data to obtain 3D image using RTM. For RTM, 20 Hz Ricker wavelet were used and grid size of x, y and z direction is 20x20x20 m. The total number of shot gathers is 176,387 and every 10th shot gather was chosen for reducing computer times and storage. The result is 3D image with inline, cross-line and depth slice image. High amplitude events are shown around (6 km, 4 km, 2.3 km) of in-line image. Each depth slice shows amplitude variation according to different depth steps. Especially channel structure variation

  2. Jupiter Clouds in Depth

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nm

    Images from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.

    Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.

    The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.

    The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter

  3. How does music aid 5 km of running?

    PubMed

    Bigliassi, Marcelo; León-Domínguez, Umberto; Buzzachera, Cosme F; Barreto-Silva, Vinícius; Altimari, Leandro R

    2015-02-01

    This research investigated the effects of music and its time of application on a 5-km run. Fifteen well-trained male long-distance runners (24.87 ± 2.47 years; 78.87 ± 10.57 kg; 178 ± 07 cm) participated in this study. Five randomized experimental conditions during a 5-km run on an official track were tested (PM: motivational songs, applied before 5 km of running; SM: slow motivational songs, applied during 5 km of running; FM: fast and motivational songs, applied during 5 km of running; CS: calm songs, applied after 5 km of running; CO: control condition). Psychophysiological assessments were performed before (functional near-infrared spectroscopy, heart rate variability [HRV], valence, and arousal), during (performance time, heart rate, and rate of perceived exertion [RPE]), and after (mood, RPE, and HRV) tests. The chosen songs were considered pleasurable and capable of activating. Furthermore, they activated the 3 assessed prefrontal cortex (PFC) areas (medial, right dorsolateral, and left dorsolateral) similarly, generating positive emotional consequences by autonomous system analysis. The first 800 m was accomplished faster for SM and FM compared with other conditions (p ≤ 0.05); moreover, there was a high probability of improving running performance when music was applied (SM: 89%; FM: 85%; PM: 39%). Finally, music was capable of accelerating vagal tonus after 5 km of running with CS (p ≤ 0.05). In conclusion, music was able to activate the PFC area, minimize perceptions, improve performance, and accelerate recovery during 5 km of running.

  4. How does music aid 5 km of running?

    PubMed

    Bigliassi, Marcelo; León-Domínguez, Umberto; Buzzachera, Cosme F; Barreto-Silva, Vinícius; Altimari, Leandro R

    2015-02-01

    This research investigated the effects of music and its time of application on a 5-km run. Fifteen well-trained male long-distance runners (24.87 ± 2.47 years; 78.87 ± 10.57 kg; 178 ± 07 cm) participated in this study. Five randomized experimental conditions during a 5-km run on an official track were tested (PM: motivational songs, applied before 5 km of running; SM: slow motivational songs, applied during 5 km of running; FM: fast and motivational songs, applied during 5 km of running; CS: calm songs, applied after 5 km of running; CO: control condition). Psychophysiological assessments were performed before (functional near-infrared spectroscopy, heart rate variability [HRV], valence, and arousal), during (performance time, heart rate, and rate of perceived exertion [RPE]), and after (mood, RPE, and HRV) tests. The chosen songs were considered pleasurable and capable of activating. Furthermore, they activated the 3 assessed prefrontal cortex (PFC) areas (medial, right dorsolateral, and left dorsolateral) similarly, generating positive emotional consequences by autonomous system analysis. The first 800 m was accomplished faster for SM and FM compared with other conditions (p ≤ 0.05); moreover, there was a high probability of improving running performance when music was applied (SM: 89%; FM: 85%; PM: 39%). Finally, music was capable of accelerating vagal tonus after 5 km of running with CS (p ≤ 0.05). In conclusion, music was able to activate the PFC area, minimize perceptions, improve performance, and accelerate recovery during 5 km of running. PMID:25029009

  5. Localization of soil depth for N uptake by Kobresia roots in Tibetan grassland

    NASA Astrophysics Data System (ADS)

    Marten Schleuß, Per-; Steingräber, Laura; Guggenberger, Georg; Kuzyakov, Yakov

    2013-04-01

    The Tibetan Plateau provides the world's largest alpine ecosystem and is dominated by Kobresia grasslands, which cover ca. 450,000 km2. Kobresia pastures are expected to be grazing-induced and are accompanied by sedge-turf varying in thickness between 5 - 30 cm. These pastoral root mat ecosystems are of global and regional importance due to its impact on global water, heat and carbon cycles, its high storage of carbon, nitrogen and other nutrients and its provision of important grazing areas, because they protect against mechanical degradation and provide a fast regrowth after heavy grazing events. Yet, less is known about the development and functioning of this Kobresia root mats. We investigated the nitrogen uptake from different soil depths mainly consisting on Kobresia root mats and N mobilisation into the soil-plant-system by localized 15N additions. A 15N pulse labeling experiment was set up in July 2012 during the vegetation period on sites of the KEMA research station (Kobresia Ecosystem Monitoring Area) near the city Nagqu. 15N urea was injected into six soil depths: 0-1 cm, 1-5 cm, 5-10 cm, 10-15 cm, 15-20 cm, 20-25 cm. Samples of soil, root and shoots were taken 45 days after the 15N labeling. Detailed description of soil profiles were carried out considering basic characteristics of single horizons. Due to low atmospheric N depositions and high N immobilization in the root mats, the study site is limited by plant available N. Hence, N uptake efficiency is assumed to be generally high and thus highest 15N amounts should be recovered in above- and belowground plant biomass. Moreover, by linking information of localization of N uptake and the morphological description of Kobresia-turf profiles, the functional purpose of single horizons can be obtained, which help to understand its successful establishment, functions and future trends with regard to change of climate and management.

  6. The isolated ˜680 km deep 30 May 2015 MW 7.9 Ogasawara (Bonin) Islands earthquake

    NASA Astrophysics Data System (ADS)

    Ye, Lingling; Lay, Thorne; Zhan, Zhongwen; Kanamori, Hiroo; Hao, Jin-Lai

    2016-01-01

    Deep-focus earthquakes, located in very high-pressure conditions 300 to 700 km below the Earth's surface within sinking slabs of relatively cold oceanic lithosphere, are mysterious phenomena. The largest recorded deep-focus earthquake (MW 7.9) in the Izu-Bonin slab struck on 30 May 2015 beneath the Ogasawara (Bonin) Islands, isolated from prior seismicity by over 100 km in depth, and followed by only a few small aftershocks. Globally, this is the deepest (680 km centroid depth) event with MW ≥ 7.8 in the seismological record. Seismicity indicates along-strike contortion of the Izu-Bonin slab, with horizontal flattening near a depth of 550 km in the Izu region and rapid steepening to near-vertical toward the south above the location of the 2015 event. This event was exceptionally well-recorded by seismic stations around the world, allowing detailed constraints to be placed on the source process. Analyses of a large global data set of P, SH and pP seismic phases using short-period back-projection, subevent directivity, and broadband finite-fault inversion indicate that the mainshock ruptured a shallowly-dipping fault plane with patchy slip that spread over a distance of ˜40 km with a multi-stage expansion rate (˜ 5 + km /s down-dip initially, ˜3 km/s up-dip later). During the 17 s total rupture duration the radiated energy was ˜ 3.3 ×1016 J and the stress drop was ˜38 MPa. The radiation efficiency is moderate (0.34), intermediate to that of the 1994 Bolivia and 2013 Sea of Okhotsk MW 8.3 deep earthquakes, indicating that source processes of very large deep earthquakes sample a wide range of behavior from dissipative, more viscous failure to very brittle failure. The isolated occurrence of the event, much deeper than the apparently thermally-bounded distribution of Bonin-slab seismicity above 600 km depth, suggests that localized stress concentration associated with the pronounced deformation of the Izu-Bonin slab and proximity to the 660-km phase transition

  7. Appraising the reliability of converted wavefield imaging: application to USArray imaging of the 410-km discontinuity

    NASA Astrophysics Data System (ADS)

    Liu, Xin; Pavlis, Gary L.

    2013-03-01

    We develop a generic method to appraise the reliability of wavefield imaging methods and use it to validate some novel observations on the 410-km discontinuity. The core concept of the error appraisal method is to produce a simulated data set that replicates the geometry of the real data. Here we implemented two simulation methods: (1) flat layer primary P to S conversions, and (2) a point source scattering model for P to S conversion data based on the Born approximation and ray theory propagators. We show how the approach can be extended for any simulation algorithm. We apply this new approach to appraise recent results using a 3-D, three-component P to S conversion imaging method applied to data collected by the USArray. Multiple metrics show that the amplitude of P to S converted energy scattered from the 410-km discontinuity varies by 18 dB with a systematically lower amplitude in an irregular band running from Idaho through northern Arizona. In addition, we observe strong lateral changes in the ratio of amplitudes recovered on the radial versus the transverse component. We compute point resolution functions and a checkerboard test to demonstrate we can reliably recover relative amplitudes with a lateral scale of the order of 200 km and a vertical scale of approximately 10 km. Irregular coverage locally distorts the amplitudes recovered in the checkerboard, but a 156 km scale checkerboard pattern is recovered. Flat layer simulations show we can recover relative amplitudes to within a range of 1 dB and the reconstructed transverse to radial amplitude is everywhere less than 0.1. A model with north-south oriented ridges with a 3° wavelength and 12.5 km amplitude shows of the order of ±6 dB amplitude variations and small, but clear correlation of the transverse/radial amplitude ratio topography in the model. Finally, we model the 410-km discontinuity as a rough surface characterized by variations in amplitude and depth derived from the USArray data. The rough

  8. Analysis of georadar data to estimate the snow depth distribution

    NASA Astrophysics Data System (ADS)

    Godio, A.; Rege, R. B.

    2016-06-01

    We have performed extensive georadar surveys for mapping the snow depth in the basin of Breuil-Cervinia (Aosta Valley) in the Italian Alps, close to the Matterhorn. More than 9 km of georadar profiles were acquired in April 2008 and 15 km in April 2009, distributed on an hydrological basin of about 12 km2. Radar surveys were carried out partially on the iced area of Ventina glacier at elevation higher than 3000 m a.s.l. and partially at lower elevation (2500 m-3000 m) on the gently slopes of the basin where the winter snow accumulated directly on the ground surface. The snow distribution on the basin, at the end of the season, could vary significantly according to the elevation range, exposition and ground morphology. In small catchment the snow depth reached 6-7 m. At higher elevation, on the glacier, a more homogeneous distribution is usually observed. A descriptive statistical analysis of the dataset is discussed to demonstrate the high spatial variability of the snow depth distribution in the area. The probability distribution of the snow depth fits the gamma distribution with a good correlation. Instead we didn't found any satisfactory relationship of the snow depth with the main morphological parameters of the terrain (elevation, slope, curvature). This suggests that the snow distribution, at the end of the winter season, is mainly conditioned by the transport phenomena and re-distribution of the wind action. The comparison of the results of georadar surveys with the hand probe measurements points out the low accuracy of the snow depth estimate in the area by using conventional hand probing approach only, encouraging to develop technology for fast and accurate mapping of the snow depth at the scale of basin.

  9. Structure and stability of H+ associates of (5,10,15,20-tetraphenylporphinato)silver(II) in trifluoroacetic acid

    NASA Astrophysics Data System (ADS)

    Bichan, N. G.; Tyulyaeva, E. Yu.; Lomova, T. N.

    2014-08-01

    Direct experimental confirmation of the formation of ion-molecular associates of (5,10,15,20-tetraphenyl-21H,23H-porphinato)silver(II) (AgTPP) with solvent protons in CF3COOH is obtained by means of 1H NMR spectroscopy. Their structure and spectral properties, as well as the kinetics of dissociation on metal-nitrogen bonds, depending on the concentration of CF3COOH (89-100%) and temperature (298-328 K), are studied It is shown that AgTPP acts as a C-base during the formation of H+ associates, the coordination centers of which have a high stability.

  10. Local fluctuations of ozone from 16 km to 45 km deduced from in situ vertical ozone profile

    NASA Technical Reports Server (NTRS)

    Moreau, G.; Robert, C.

    1994-01-01

    A vertical ozone profile obtained by an in situ ozone sonde from 16 km to 45 km, has allowed to observe local ozone concentration variations. These variations can be observed, thanks to a fast measurement system based on a UV absorption KrF excimer laser beam in a multipass cell. Ozone standard deviation versus altitude calculated from the mean is derived. Ozone variations or fluctuations are correlated with the different dynamic zones of the stratosphere.

  11. The KM3NeT Digital Optical Module

    NASA Astrophysics Data System (ADS)

    Vivolo, Daniele

    2016-04-01

    KM3NeT is a European deep-sea multidisciplinary research infrastructure in the Mediterranean Sea. It will host a km3-scale neutrino telescope and dedicated instruments for long-term and continuous measurements for Earth and Sea sciences. The KM3NeT neutrino telescope is a 3-dimensional array of Digital Optical Modules, suspended in the sea by means of vertical string structures, called Detection Units, supported by two pre-stretched Dyneema ropes, anchored to the seabed and kept taut with a system of buoys. The Digital Optical Module represents the active part of the neutrino telescope. It is composed by a 17-inch, 14 mm thick borosilicate glass (Vitrovex) spheric vessel housing 31 photomultiplier tubes with 3-inch photocathode diameter and the associated front-end and readout electronics. The technical solution adopted for the KM3NeT optical modules is characterized by an innovative design, considering that existing neutrino telescopes, Baikal, IceCube and ANTARES, all use large photomultipliers, typically with a diameter of 8″ or 10″. It offers several advantages: higher sensitive surface (1260 cm2), weaker sensitivity to Earth's magnetic field, better distinction between single-photon and multi-photon events (photon counting) and directional information with an almost isotropic field of view. In this contribution the design and the performance of the KM3NeT Digital Optical Modules are discussed, with a particular focus on enabling technologies and integration procedure.

  12. Gravity Waves Near 300 km Over the Polar Caps

    NASA Technical Reports Server (NTRS)

    Johnson, F. S.; Hanson, W. B.; Hodges, R. R.; Coley, W. R.; Carignan, G. R.; Spencer, N. W.

    1995-01-01

    Distinctive wave forms in the distributions of vertical velocity and temperature of both neutral particles and ions are frequently observed from Dynamics Explorer 2 at altitudes above 250 km over the polar caps. These are interpreted as being due to internal gravity waves propagating in the neutral atmosphere. The disturbances characterized by vertical velocity perturbations of the order of 100 m/s and horizontal wave lengths along the satellite path of about 500 km. They often extend across the entire polar cap. The associated temperature perturbations indicate that the horizontal phase progression is from the nightside to the dayside. Vertical displacements are inferred to be of the order of 10 km and the periods to be of the order of 10(exp 3) s. The waves must propagate in the neutral atmosphere, but they usually are most clearly recognizable in the observations of ion vertical velocity and ion temperature. By combining the neutral pressure calculated from the observed neutral concentration and temperature with the vertical component of the neutral velocity, an upward energy flux of the order of 0.04 erg/sq cm-s at 250 km has been calculated, which is about equal to the maximum total solar ultraviolet heat input above that altitude. Upward energy fluxes calculated from observations on orbital passes at altitudes from 250 to 560 km indicate relatively little attenuation with altitude.

  13. Flood-depth frequency relations for streams in Alabama

    USGS Publications Warehouse

    Olin, D.A.

    1986-01-01

    Equations were defined for estimating the depth of water for floods having recurrence intervals of 2, 5, 10, 25, 50, 100, and 200 years on rural and urban streams in Alabama. Multiple regression analyses were made using the ' maximum RSQUARE improvement ' procedures. The dependent variable was the flood depth and the independent variables were 10 basin and climatic characteristics. For rural streams, drainage area size (0.44 to 1,344 sq mi) was the only statistically significant independent variable tested to estimate flood depths in six different hydrologic areas. Other variables affecting flood depth relations are reflected in the equation constant and coefficient for each hydrologic area. These account for differences in geologic and topographic characteristics. For urban streams, drainage area size (0.16 to 83.5 sq mi) and percent impervious area (8.3% to 42.9%) of the basin were the most significant independent variables tested to estimate flood depths. For most streams where the drainage area is > 1,344 sq mi, the drainage basin extends into more than one hydrologic area and the equations presented would not apply. Flood profile data and gaging station records are available from the U.S. Geological Survey for use in estimating flood depths for these large streams. Flood routing and historic flood profiles are also available for many of the large streams which have flood regulation. (Author 's abstract)

  14. Aerosol Optical Depth Determinations for BOREAS

    NASA Technical Reports Server (NTRS)

    Wrigley, R. C.; Livingston, J. M.; Russell, P. B.; Guzman, R. P.; Ried, D.; Lobitz, B.; Peterson, David L. (Technical Monitor)

    1994-01-01

    Automated tracking sun photometers were deployed by NASA/Ames Research Center aboard the NASA C-130 aircraft and at a ground site for all three Intensive Field Campaigns (IFCs) of the Boreal Ecosystem-Atmosphere Study (BOREAS) in central Saskatchewan, Canada during the summer of 1994. The sun photometer data were used to derive aerosol optical depths for the total atmospheric column above each instrument. The airborne tracking sun photometer obtained data in both the southern and northern study areas at the surface prior to takeoff, along low altitude runs near the ground tracking sun photometer, during ascents to 6-8 km msl, along remote sensing flightlines at altitude, during descents to the surface, and at the surface after landing. The ground sun photometer obtained data from the shore of Candle Lake in the southern area for all cloud-free times. During the first IFC in May-June ascents and descents of the airborne tracking sun photometer indicated the aerosol optical depths decreased steadily from the surface to 3.5 kni where they leveled out at approximately 0.05 (at 525 nm), well below levels caused by the eruption of Mt. Pinatubo. On a very clear day, May 31st, surface optical depths measured by either the airborne or ground sun photometers approached those levels (0.06-0.08 at 525 nm), but surface optical depths were often several times higher. On June 4th they increased from 0.12 in the morning to 0.20 in the afternoon with some evidence of brief episodes of pollen bursts. During the second IFC surface aerosol optical depths were variable in the extreme due to smoke from western forest fires. On July 20th the aerosol optical depth at 525 nm decreased from 0.5 in the morning to 0.2 in the afternoon; they decreased still further the next day to 0.05 and remained consistently low throughout the day to provide excellent conditions for several remote sensing missions flown that day. Smoke was heavy for the early morning of July 24th but cleared partially by 10

  15. Slab tears and intermediate-depth seismicity

    USGS Publications Warehouse

    Meighan, Hallie E.; Ten Brink, Uri; Pulliam, Jay

    2013-01-01

    Active tectonic regions where plate boundaries transition from subduction to strike slip can take several forms, such as triple junctions, acute, and obtuse corners. Well-documented slab tears that are associated with high rates of intermediate-depth seismicity are considered here: Gibraltar arc, the southern and northern ends of the Lesser Antilles arc, and the northern end of Tonga trench. Seismicity at each of these locations occurs, at times, in the form of swarms or clusters, and various authors have proposed that each marks an active locus of tear propagation. The swarms and clusters start at the top of the slab below the asthenospheric wedge and extend 30–60 km vertically downward within the slab. We propose that these swarms and clusters are generated by fluid-related embrittlement of mantle rocks. Focal mechanisms of these swarms generally fit the shear motion that is thought to be associated with the tearing process.

  16. The -145 km/S Absorption System of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, T. R.; Danks, A.; Johansson, S.

    2002-01-01

    With the STIS E230H mode (R-118,000) , we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 W s , are quite different in character from the others, mostly at intermediate velocities. The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000/cm, well above the 2000/cm noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes.

  17. Potential of KM+ lectin in immunization against Leishmania amazonensis infection.

    PubMed

    Teixeira, Clarissa R; Cavassani, Karen A; Gomes, Regis B; Teixeira, Maria Jania; Roque-Barreira, Maria-Cristina; Cavada, Benildo S; da Silva, João Santana; Barral, Aldina; Barral-Netto, Manoel

    2006-04-01

    In the present study we evaluated Canavalia brasiliensis (ConBr), Pisum arvense (PAA) and Artocarpus integrifolia (KM+) lectins as immunostimulatory molecules in vaccination against Leishmania amazonensis infection. Although they induced IFN-gamma production, the combination of the lectins with SLA antigen did not lead to lesion reduction. However, parasite load was largely reduced in mice immunized with KM+ lectin and SLA. KM+ induced a smaller inflammatory reaction in the air pouch model and was able to inhibit differentiation of dendritic cells (BMDC), but to induce maturation by enhancing the expression of MHC II, CD80 and CD86. These observations indicate the modulatory role of plant lectins in leishmaniasis vaccination may be related to their action on the initial innate response.

  18. Stereo depth distortions in teleoperation

    NASA Technical Reports Server (NTRS)

    Diner, Daniel B.; Vonsydow, Marika

    1988-01-01

    In teleoperation, a typical application of stereo vision is to view a work space located short distances (1 to 3m) in front of the cameras. The work presented here treats converged camera placement and studies the effects of intercamera distance, camera-to-object viewing distance, and focal length of the camera lenses on both stereo depth resolution and stereo depth distortion. While viewing the fronto-parallel plane 1.4 m in front of the cameras, depth errors are measured on the order of 2cm. A geometric analysis was made of the distortion of the fronto-parallel plane of divergence for stereo TV viewing. The results of the analysis were then verified experimentally. The objective was to determine the optimal camera configuration which gave high stereo depth resolution while minimizing stereo depth distortion. It is found that for converged cameras at a fixed camera-to-object viewing distance, larger intercamera distances allow higher depth resolutions, but cause greater depth distortions. Thus with larger intercamera distances, operators will make greater depth errors (because of the greater distortions), but will be more certain that they are not errors (because of the higher resolution).

  19. Perception of relative depth interval: systematic biases in perceived depth.

    PubMed

    Harris, Julie M; Chopin, Adrien; Zeiner, Katharina; Hibbard, Paul B

    2012-01-01

    Given an estimate of the binocular disparity between a pair of points and an estimate of the viewing distance, or knowledge of eye position, it should be possible to obtain an estimate of their depth separation. Here we show that, when points are arranged in different vertical geometric configurations across two intervals, many observers find this task difficult. Those who can do the task tend to perceive the depth interval in one configuration as very different from depth in the other configuration. We explore two plausible explanations for this effect. The first is the tilt of the empirical vertical horopter: Points perceived along an apparently vertical line correspond to a physical line of points tilted backwards in space. Second, the eyes can rotate in response to a particular stimulus. Without compensation for this rotation, biases in depth perception would result. We measured cyclovergence indirectly, using a standard psychophysical task, while observers viewed our depth configuration. Biases predicted from error due either to cyclovergence or to the tilted vertical horopter were not consistent with the depth configuration results. Our data suggest that, even for the simplest scenes, we do not have ready access to metric depth from binocular disparity.

  20. Simulation of CO2 release at 800 km altitude

    NASA Astrophysics Data System (ADS)

    Setayesh, A.

    1993-08-01

    The SOCRATES contamination-interaction code has been used to simulate the reactions of 0 + CO2 yields CO2(v) + O, O + CO2 - CO(v) + O2, and CO2 + H - CO + OH(v) at an altitude of 800 km in both ram and wake directions of the spacecraft. These simulations show that the radiation from these reactions can be measurable for the parameters which have been used in these calculations. The investigation carries out the simulations as much as 30 km from the spacecraft. The radiative intensity of CO(v) and OH(v) show the highest and lowest, respectively.

  1. Cascade sensitivity studies for KM3NeT

    NASA Astrophysics Data System (ADS)

    Fusco, Luigi Antonio

    2016-07-01

    KM3NeT is a future research infrastructure in the deep seas of the Mediterranean housing a large scale neutrino telescope. The first phase of construction of the telescope has started. Next step is an intermediate phase realising a detector volume of about one-third of the final detector volume. We report on calculations of the sensitivity of the KM3NeT detector to showering neutrino events, the strategy to optimise the detector to a cosmic neutrino flux analogous to the one reported by the IceCube Collaboration and the results of this strategy applied to the intermediate phase detector.

  2. From NEMO to KM3NeT-Italy

    NASA Astrophysics Data System (ADS)

    Nicolau, Carlo A.

    2014-04-01

    The KM3NeT-Italy Collaboration has entered the production stage of an 8 tower apparatus that will be deployed at about 100 km off the Sicily coast. The architecture of the system is based on the NEMO Phase2 prototype tower which is taking data since the deployment in March 2013. In order to optimize production costs, power consumption, and usability, some components have been re-engineered by taking advantage of the previously gained experience and technological progress. The aim of this contribution is to give an overview of the main features that characterize the new apparatus.

  3. Crude oil degradation as an explanation of the depth rule

    USGS Publications Warehouse

    Price, L.C.

    1980-01-01

    Previous studies of crude oil degradation by water washing and bacterial attack have documented the operation of these processes in many different petroleum basins of the world. Crude oil degradation substantially alters the chemical and physical makeup of a crude oil, changing a light paraffinic low-S "mature" crude to a heavy naphthenic or asphalt base, "immature appearing" high-S crude. Rough calculations carried out in the present study using experimentally determined solubility data of petroleum in water give insight into the possible magnitude of water washing and suggest that the process may be able to remove large amounts of petroleum in small divisions of geologic time. Plots of crude oil gravity vs. depth fail to show the expected correlation of increasing API gravity (decreasing specific gravity) with depth below 2.44 km (8000 ft.). Previous studies which have been carried out to document in-reservoir maturation have used crude oil gravity data shallower than 2.44 km (8000 ft.). The changes in crude oil composition as a function of depth which have been attributed to in-reservoir maturation over these shallower depths, are better explained by crude oil degradation. This study concludes that changes in crude oil composition that result from in-reservoir maturation are not evident from existing crude oil gravity data over the depth and temperature range previously supposed, and that the significant changes in crude oil gravity which are present over the shallow depth range are due to crude oil degradation. Thus the existence of significant quantities of petroleum should not necessarily be ruled out below an arbitrarily determined depth or temperature limit when the primary evidence for this is the change in crude oil gravity at shallow depths. ?? 1980.

  4. Multistep joint bilateral depth upsampling

    NASA Astrophysics Data System (ADS)

    Riemens, A. K.; Gangwal, O. P.; Barenbrug, B.; Berretty, R.-P. M.

    2009-01-01

    Depth maps are used in many applications, e.g. 3D television, stereo matching, segmentation, etc. Often, depth maps are available at a lower resolution compared to the corresponding image data. For these applications, depth maps must be upsampled to the image resolution. Recently, joint bilateral filters are proposed to upsample depth maps in a single step. In this solution, a high-resolution output depth is computed as a weighted average of surrounding low-resolution depth values, where the weight calculation depends on spatial distance function and intensity range function on the related image data. Compared to that, we present two novel ideas. Firstly, we apply anti-alias prefiltering on the high-resolution image to derive an image at the same low resolution as the input depth map. The upsample filter uses samples from both the high-resolution and the low-resolution images in the range term of the bilateral filter. Secondly, we propose to perform the upsampling in multiple stages, refining the resolution by a factor of 2×2 at each stage. We show experimental results on the consequences of the aliasing issue, and we apply our method to two use cases: a high quality ground-truth depth map and a real-time generated depth map of lower quality. For the first use case a relatively small filter footprint is applied; the second use case benefits from a substantially larger footprint. These experiments show that the dual image resolution range function alleviates the aliasing artifacts and therefore improves the temporal stability of the output depth map. On both use cases, we achieved comparable or better image quality with respect to upsampling with the joint bilateral filter in a single step. On the former use case, we feature a reduction of a factor of 5 in computational cost, whereas on the latter use case, the cost saving is a factor of 50.

  5. Curie Point Depth Estimates and Correlation with Subduction in Mexico

    NASA Astrophysics Data System (ADS)

    Manea, Marina; Manea, Vlad C.

    2011-08-01

    We investigate the regional thermal structure of the crust in Mexico using Curie Point Depth (CPD) estimates. The top and bottom of the magnetized crust were calculated using the power-density spectra of the total magnetic field from the freely available "Magnetic Anomaly Map of North America". We applied this method to estimate the regional crustal thermal structure in overlapping square windows of 2° × 2°. The CPD estimates range between 10 and 40 km and show several regions of relatively shallow and deep magnetic sources, with a general inverse correlation with measured heat flow. A deep CPD region (20-30 km) is located in the fore-arc area where the subducting Cocos plate has a flat-slab geometry. This deep region is bound to the NW and SE by shallow CPD areas beneath the states of Michoacan (CPD = 12-16 km) and Oaxaca (CPD = ~16 km), respectively. There is a good spatial correlation between this deep CPD area and two main fracture zones located on the incoming Cocos plate (Orozco and O'Gorman fracture zones), suggesting that subduction plays an important role in setting apart different CPD provinces along the Mexican coast. Another deep CPD (16-32 km) area corresponds to the region where the Rivera plate subducts beneath Jalisco block. The Trans-Mexican Volcanic Belt is characterized by a decrease in Curie depths from west (16-20 km) to east (10-12 km). Finally, several deep CPD areas are situated in the back-arc region where old Mesozoic terrains are present. Our results suggest that the main control on the crust's regional thermal structure in the fore-arc and volcanic arc regions is due to the subduction of the Cocos and Rivera plates beneath Mexico.

  6. SoilGrids1km — Global Soil Information Based on Automated Mapping

    PubMed Central

    Hengl, Tomislav; de Jesus, Jorge Mendes; MacMillan, Robert A.; Batjes, Niels H.; Heuvelink, Gerard B. M.; Ribeiro, Eloi; Samuel-Rosa, Alessandro; Kempen, Bas; Leenaars, Johan G. B.; Walsh, Markus G.; Gonzalez, Maria Ruiperez

    2014-01-01

    Background Soils are widely recognized as a non-renewable natural resource and as biophysical carbon sinks. As such, there is a growing requirement for global soil information. Although several global soil information systems already exist, these tend to suffer from inconsistencies and limited spatial detail. Methodology/Principal Findings We present SoilGrids1km — a global 3D soil information system at 1 km resolution — containing spatial predictions for a selection of soil properties (at six standard depths): soil organic carbon (g kg−1), soil pH, sand, silt and clay fractions (%), bulk density (kg m−3), cation-exchange capacity (cmol+/kg), coarse fragments (%), soil organic carbon stock (t ha−1), depth to bedrock (cm), World Reference Base soil groups, and USDA Soil Taxonomy suborders. Our predictions are based on global spatial prediction models which we fitted, per soil variable, using a compilation of major international soil profile databases (ca. 110,000 soil profiles), and a selection of ca. 75 global environmental covariates representing soil forming factors. Results of regression modeling indicate that the most useful covariates for modeling soils at the global scale are climatic and biomass indices (based on MODIS images), lithology, and taxonomic mapping units derived from conventional soil survey (Harmonized World Soil Database). Prediction accuracies assessed using 5–fold cross-validation were between 23–51%. Conclusions/Significance SoilGrids1km provide an initial set of examples of soil spatial data for input into global models at a resolution and consistency not previously available. Some of the main limitations of the current version of SoilGrids1km are: (1) weak relationships between soil properties/classes and explanatory variables due to scale mismatches, (2) difficulty to obtain covariates that capture soil forming factors, (3) low sampling density and spatial clustering of soil profile locations. However, as the Soil

  7. Method of using 5,10,15,20-tetrakis(carboxyphenyl)porphine for detecting cancers of the lung

    DOEpatents

    Cole, D.A.; Moody, D.C. III; Ellinwood, L.E.; Klein, M.G.

    1992-11-10

    A method is described for using tetra-aryl porphyrins for and, in particular, 5,10,15,20-tetrakis(4-carboxyphenyl)porphine as a fluorescent tracer for cancers of the lung, and as a radiotracer therefor as a complex with [sup 67]Cu. The latter complex also provides a source of beta radiation for selective destruction of lung malignancies as well as gamma radiation useful for image analysis of the lungs by single photon emission computed tomography, as an example, both in vivo. Copper-64 may be substituted for the [sup 67]Cu if only radiotracer characteristics are of interest. This lighter isotope of copper is a positron emitter, and positron emission tomography techniques can be used to locate the malignant tissue mass. 1 figure.

  8. Method using 5,10,15,20-tetrakis(4-carboxyphenyl)porphine for treating cancers of the lung

    DOEpatents

    Cole, Dean A.; Moody, III, David C.; Ellinwood, L. Edward; Klein, M. Gerard

    1995-01-01

    Method using tetra-aryl porphyrins for and, in particular, 5,10,15,20-tetrakis(4-carboxyphenyl)porphine as a fluorescent tracer for cancers of the lung, and as a radiotracer therefor as a complex with .sup.67 Cu. The latter complex also provides a source of beta radiation for selective destruction of lung malignancies as well as gamma radiation useful for image analysis of the situs thereof by single photon emission computed tomography, as an example, both in vivo. Copper-64 may be substituted for the .sup.67 Cu if only radiotracer characteristics are of interest. This lighter isotope of copper is a positron emitter, and positron emission tomography techniques can be used to locate the malignant tissue mass.

  9. Method of using 5,10,15,20-tetrakis(carboxyphenyl)porphine for detecting cancers of the lung

    DOEpatents

    Cole, Dean A.; Moody, III, David C.; Ellinwood, L. Edward; Klein, M. Gerard

    1992-01-01

    Method using tetra-aryl porphyrins for and, in particular, 5,10,15,20-tetrakis(4-carboxyphenyl)porphine as a fluorescent tracer for cancers of the lung, and as a radiotracer therefor as a complex with .sup.67 Cu. The latter complex also provides a source of beta radiation for selective destruction of lung malignancies as well as gamma radiation useful for image analysis of the situs thereof by single photon emission computed tomography, as an example, both in vivo. Copper-64 may be substituted for the .sup.67 Cu if only radiotracer characteristics are of interest. This lighter isotope of copper is a positron emitter, and positron emission tomography techniques cna be used to locate the malignant tissue mass.

  10. Presence of the 5,10-methylenetetrahydrofolate reductase C677T mutation in Puerto Rican patients with neural tube defects.

    PubMed

    García-Fragoso, Lourdes; García-García, Inés; de la Vega, Alberto; Renta, Jessicca; Cadilla, Carmen L

    2002-01-01

    Folic acid supplementation can reduce the incidence of neural tube defects. The first reported genetic risk factor for neural tube defects is a C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene, resulting in decreased activity of the enzyme. We examined the enzyme mutation role of methylenetetrahydrofolate reductase in the etiology of neural tube defects in our population. The study group consisted of 204 Puerto Rican individuals including 37 pregnant females with a prenatal diagnosis of neural tube defects in their fetuses, 31 newborns, 36 fathers, and 100 healthy adults. The prevalence of the C677T mutation was examined. Homozygosity for the alanine to valine substitution (TT) was observed in 9% of the controls and 19% of the mothers with children with neural tube defects. Our results indicate that the presence of the T allele at the methylenetetrahydrofolate reductase 677 position may increase the risk of giving birth to an infant with a neural tube defect.

  11. Body Composition Measurements of 161-km Ultramarathon Participants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study compares body composition characteristics with performance among participants in a 161-km trail ultramarathon. Height, mass, and percent body fat from bioimpedence spectroscopy were measured on 72 starters. Correlation analyses were used to compare body characteristics with finish time, ...

  12. The -145 km/s Absorption System of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Vieira, G. L.; Gull, T. R.; Danks, A. C.; Johansson, S.

    2002-12-01

    With the STIS E230H mode (R 118,000), we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 km/s, are quite different in character from the others, mostly at intermediate velocities (See adjacent posters by T. Gull and A. Danks). The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000 cm-1, well above the 2000 cm-1 noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes. Observations were accomplished through STScI under proposal 9242 (Danks, P.I.). Funding is through the STIS GTO resources.

  13. Models of earth's atmosphere (90 to 2500 km)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This monograph replaces a monograph on the upper atmosphere which was a computerized version of Jacchia's model. The current model has a range from 90 to 2500 km. In addition to the computerized model, a quick-look prediction method is given that may be used to estimate the density for any time and spatial location without using a computer.

  14. Gravity wave vertical energy flux at 95 km

    NASA Technical Reports Server (NTRS)

    Jacob, P. G.; Jacka, F.

    1985-01-01

    A three-field photometer (3FP) located at Mt. Torrens near Adelaide, is capable of monitoring different airglow emissions from three spaced fields in the sky. A wheel containing up to six different narrow bandpass interference filters can be rotated, allowing each of the filters to be sequentially placed into each of the three fields. The airglow emission of interest is the 557.7 nm line which has an intensity maximum at 95 km. Each circular field of view is located at the apexes of an equilateral triangle centered on zenith with diameters of 5 km and field separations of 13 km when projected to the 95-km level. The sampling period was 30 seconds and typical data lengths were between 7 and 8 hours. The analysis and results from the interaction of gravity waves on the 557.7 nm emission layer are derived using an atmospheric model similar to that proposed by Hines (1960) where the atmosphere is assumed isothermal and perturbations caused by gravity waves are small and adiabatic, therefore, resulting in linearized equations of motion. In the absence of waves, the atmosphere is also considered stationary. Thirteen nights of quality data from January 1983 to October 1984, covering all seasons, are used in this analysis.

  15. Treatment of the edentulous atrophic maxilla using zygomatic implants: evaluation of survival rates over 5-10 years.

    PubMed

    Yates, J M; Brook, I M; Patel, R R; Wragg, P F; Atkins, S A; El-Awa, A; Bakri, I; Bolt, R

    2014-02-01

    The aim of this retrospective observational cohort study was to analyse and report the 5-10-year survival rates of endosseous zygomatic implants used in the rehabilitation of the atrophic maxilla. Forty-three consecutive zygomatic implant placements in 25 patients were evaluated over a 5-10-year period. All zygomatic implant surgery was carried out under general anaesthesia. Nobel Biocare zygomatic machined-surface implants were used, and placement was undertaken using the modified sinus slot method. The main outcome measures and determinants for success were survival of the restored implants and the proportion of originally planned prostheses delivered to patients. Of the 25 patients treated, 12 were male and 13 were female; 19 were non-smokers, and the mean age at time of surgery was 64 years. Patients were treatment-planned for implant-retained bridgework, a removable prosthesis retained by fixed cast gold or milled titanium beams, or magnet-retained removable prostheses. A combination of zygomatic and conventional implants was used in all but one patient. In this study it was shown that the overall success rate for zygomatic implants was 86%, with six of the implants either failing to integrate or requiring removal due to persistent infection associated with the maxillary sinus. All patients received their planned prosthesis, although in six cases the method of retention required modification. This study illustrates that zygomatic implants are a successful and important treatment option when trying to restore the atrophic maxilla, with the potential to avoid additional augmentation/grafting procedures and resulting in a high long-term success rate. PMID:24120903

  16. On evaluation of depth accuracy in consumer depth sensors

    NASA Astrophysics Data System (ADS)

    Abd Aziz, Azim Zaliha; Wei, Hong; Ferryman, James

    2015-12-01

    This paper presents an experimental study of different depth sensors. The aim is to answer the question, whether these sensors give accurate data for general depth image analysis. The study examines the depth accuracy between three popularly used depth sensors; ASUS Xtion Prolive, Kinect Xbox 360 and Kinect for Windows v2. The main attention is to study on the stability of pixels in the depth image captured at several different sensor-object distances by measuring the depth returned by the sensors within specified time intervals. The experimental results show that the fluctuation (mm) of the random selected pixels within the target area, increases with increasing distance to the sensor, especially on the Kinect for Xbox 360 and the Asus Xtion Prolive. Both of these sensors provide pixels fluctuation between 20mm and 30mm at a sensor-object distance beyond 1500mm. However, the pixel's stability of the Kinect for Windows v2 not affected much with the distance between the sensor and the object. The maximum fluctuation for all the selected pixels of Kinect for Windows v2 is approximately 5mm at sensor-object distance of between 800mm and 3000mm. Therefore, in the optimal distance, the best stability achieved.

  17. Microphysical and Dynamical Influences on Cirrus Cloud Optical Depth Distributions

    SciTech Connect

    Kay, J.; Baker, M.; Hegg, D.

    2005-03-18

    Cirrus cloud inhomogeneity occurs at scales greater than the cirrus radiative smoothing scale ({approx}100 m), but less than typical global climate model (GCM) resolutions ({approx}300 km). Therefore, calculating cirrus radiative impacts in GCMs requires an optical depth distribution parameterization. Radiative transfer calculations are sensitive to optical depth distribution assumptions (Fu et al. 2000; Carlin et al. 2002). Using raman lidar observations, we quantify cirrus timescales and optical depth distributions at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site in Lamont, OK (USA). We demonstrate the sensitivity of outgoing longwave radiation (OLR) calculations to assumed optical depth distributions and to the temporal resolution of optical depth measurements. Recent work has highlighted the importance of dynamics and nucleation for cirrus evolution (Haag and Karcher 2004; Karcher and Strom 2003). We need to understand the main controls on cirrus optical depth distributions to incorporate cirrus variability into model radiative transfer calculations. With an explicit ice microphysics parcel model, we aim to understand the influence of ice nucleation mechanism and imposed dynamics on cirrus optical depth distributions.

  18. Moho depth derived from gravity and magnetic data in the Southern Atlas Flexure (Algeria)

    NASA Astrophysics Data System (ADS)

    Meliani, O.; Bourmatte, A.; Hamoudi, M.; Haddoum, H.; Quesnel, Y.

    2016-09-01

    Existing aeromagnetic and gravity data were used to study the structure of the Southern Atlas Flexure (SAF) in Algeria. Forward and inverse numerical modelings were applied, giving access to the depth of the Moho and the Curie depth in this area. Our results suggest a maximum crustal thickness of about 48 km, and a Curie depth of about 20 km. We then discuss the implications of those results on the regional structure of the SAF, also using cross-sections built using 2D-geological modeling.

  19. The prototype detection unit of the KM3NeT detector

    NASA Astrophysics Data System (ADS)

    Adrián-Martínez, S.; Ageron, M.; Aharonian, F.; Aiello, S.; Albert, A.; Ameli, F.; Anassontzis, E. G.; Androulakis, G. C.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Avgitas, T.; Balasi, K.; Band, H.; Barbarino, G.; Barbarito, E.; Barbato, F.; Baret, B.; Baron, S.; Barrios, J.; Belias, A.; Berbee, E.; van den Berg, A. M.; Berkien, A.; Bertin, V.; Beurthey, S.; van Beveren, V.; Beverini, N.; Biagi, S.; Biagioni, A.; Bianucci, S.; Billault, M.; Birbas, A.; Boer Rookhuizen, H.; Bormuth, R.; Bouché, V.; Bouhadef, B.; Bourlis, G.; Boutonnet, C.; Bouwhuis, M.; Bozza, C.; Bruijn, R.; Brunner, J.; Cacopardo, G.; Caillat, L.; Calamai, M.; Calvo, D.; Capone, A.; Caramete, L.; Caruso, F.; Cecchini, S.; Ceres, A.; Cereseto, R.; Champion, C.; Château, F.; Chiarusi, T.; Christopoulou, B.; Circella, M.; Classen, L.; Cocimano, R.; Coleiro, A.; Colonges, S.; Coniglione, R.; Cosquer, A.; Costa, M.; Coyle, P.; Creusot, A.; Cuttone, G.; D'Amato, C.; D'Amico, A.; De Bonis, G.; De Rosa, G.; Deniskina, N.; Destelle, J.-J.; Distefano, C.; Di Capua, F.; Donzaud, C.; Dornic, D.; Dorosti-Hasankiadeh, Q.; Drakopoulou, E.; Drouhin, D.; Drury, L.; Durand, D.; Eberl, T.; Elsaesser, D.; Enzenhöfer, A.; Fermani, P.; Fusco, L. A.; Gajanana, D.; Gal, T.; Galatà, S.; Garufi, F.; Gebyehu, M.; Giordano, V.; Gizani, N.; Gracia Ruiz, R.; Graf, K.; Grasso, R.; Grella, G.; Grmek, A.; Habel, R.; van Haren, H.; Heid, T.; Heijboer, A.; Heine, E.; Henry, S.; Hernández-Rey, J. J.; Herold, B.; Hevinga, M. A.; van der Hoek, M.; Hofestädt, J.; Hogenbirk, J.; Hugon, C.; Hößl, J.; Imbesi, M.; James, C. W.; Jansweijer, P.; Jochum, J.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Kappos, E.; Katz, U.; Kavatsyuk, O.; Keller, P.; Kieft, G.; Koffeman, E.; Kok, H.; Kooijman, P.; Koopstra, J.; Korporaal, A.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Le Provost, H.; Leismüller, K. P.; Leisos, A.; Lenis, D.; Leonora, E.; Lindsey Clark, M.; Llorens Alvarez, C. D.; Löhner, H.; Lonardo, A.; Loucatos, S.; Louis, F.; Maccioni, E.; Mannheim, K.; Manolopoulos, K.; Margiotta, A.; Mariş, O.; Markou, C.; Martínez-Mora, J. A.; Martini, A.; Masullo, R.; Melis, K. W.; Michael, T.; Migliozzi, P.; Migneco, E.; Miraglia, A.; Mollo, C. M.; Mongelli, M.; Morganti, M.; Mos, S.; Moudden, Y.; Musico, P.; Musumeci, M.; Nicolaou, C.; Nicolau, C. A.; Orlando, A.; Orzelli, A.; Papaikonomou, A.; Papaleo, R.; Păvălaş, G. E.; Peek, H.; Pellegrino, C.; Pellegriti, M. G.; Perrina, C.; Piattelli, P.; Pikounis, K.; Popa, V.; Pradier, Th.; Priede, M.; Pühlhofer, G.; Pulvirenti, S.; Racca, C.; Raffaelli, F.; Randazzo, N.; Rapidis, P. A.; Razis, P.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Rovelli, A.; Saldaña, M.; Samtleben, D. F. E.; Sanguineti, M.; Santangelo, A.; Sapienza, P.; Schmelling, J.; Schnabel, J.; Sciacca, V.; Sedita, M.; Seitz, T.; Sgura, I.; Simeone, F.; Sipala, V.; Spitaleri, A.; Spurio, M.; Stavropoulos, G.; Steijger, J.; Stolarczyk, T.; Stransky, D.; Taiuti, M.; Terreni, G.; Tézier, D.; Théraube, S.; Thompson, L. F.; Timmer, P.; Trasatti, L.; Trovato, A.; Tselengidou, M.; Tsirigotis, A.; Tzamarias, S.; Tzamariudaki, E.; Vallage, B.; Van Elewyck, V.; Vermeulen, J.; Vernin, P.; Vicini, P.; Viola, S.; Vivolo, D.; Werneke, P.; Wiggers, L.; Wilms, J.; de Wolf, E.; van Wooning, R. H. L.; Zonca, E.; Zornoza, J. D.; Zúñiga, J.; Zwart, A.

    2016-02-01

    A prototype detection unit of the KM3NeT deep-sea neutrino telescope has been installed at 3500m depth 80 km offshore the Italian coast. KM3NeT in its final configuration will contain several hundreds of detection units. Each detection unit is a mechanical structure anchored to the sea floor, held vertical by a submerged buoy and supporting optical modules for the detection of Cherenkov light emitted by charged secondary particles emerging from neutrino interactions. This prototype string implements three optical modules with 31 photomultiplier tubes each. These optical modules were developed by the KM3NeT Collaboration to enhance the detection capability of neutrino interactions. The prototype detection unit was operated since its deployment in May 2014 until its decommissioning in July 2015. Reconstruction of the particle trajectories from the data requires a nanosecond accuracy in the time calibration. A procedure for relative time calibration of the photomultiplier tubes contained in each optical module is described. This procedure is based on the measured coincidences produced in the sea by the ^{40}K background light and can easily be expanded to a detector with several thousands of optical modules. The time offsets between the different optical modules are obtained using LED nanobeacons mounted inside them. A set of data corresponding to 600 h of livetime was analysed. The results show good agreement with Monte Carlo simulations of the expected optical background and the signal from atmospheric muons. An almost background-free sample of muons was selected by filtering the time correlated signals on all the three optical modules. The zenith angle of the selected muons was reconstructed with a precision of about 3°.

  20. Sedimentary basins reconnaissance using the magnetic Tilt-Depth method

    NASA Astrophysics Data System (ADS)

    Salem, Ahmed; Williams, Simon; Samson, Esuene; Fairhead, Derek; Ravat, Dhananjay; Blakely, Richard J.

    2010-09-01

    We compute the depth to the top of magnetic basement using the Tilt-Depth method from the best available magnetic anomaly grids covering the continental USA and Australia. For the USA, the Tilt-Depth estimates were compared with sediment thicknesses based on drilling data and show a correlation of 0.86 between the datasets. If random data were used then the correlation value goes to virtually zero. There is little to no lateral offset of the depth of basinal features although there is a tendency for the Tilt-Depth results to be slightly shallower than the drill depths. We also applied the Tilt-Depth method to a local-scale, relatively high-resolution aeromagnetic survey over the Olympic Peninsula of Washington State. The Tilt-Depth method successfully identified a variety of important tectonic elements known from geological mapping. Of particular interest, the Tilt-Depth method illuminated deep (3km) contacts within the non-magnetic sedimentary core of the Olympic Mountains, where magnetic anomalies are subdued and low in amplitude. For Australia, the Tilt-Depth estimates also give a good correlation with known areas of shallow basement and sedimentary basins. Our estimates of basement depth are not restricted to regional analysis but work equally well at the micro scale (basin scale) with depth estimates agreeing well with drill hole and seismic data. We focus on the eastern Officer Basin as an example of basin scale studies and find a good level of agreement between previously-derived basin models. However, our study potentially reveals depocentres not previously mapped due to the sparse distribution of well data. This example thus shows the potential additional advantage of the method in geological interpretation. The success of this study suggests that the Tilt-Depth method is useful in estimating the depth to crystalline basement when appropriate quality aeromagnetic anomaly data are used (i.e. line spacing on the order of or less than the expected depth to

  1. Sedimentary basins reconnaissance using the magnetic Tilt-Depth method

    USGS Publications Warehouse

    Salem, A.; Williams, S.; Samson, E.; Fairhead, D.; Ravat, D.; Blakely, R.J.

    2010-01-01

    We compute the depth to the top of magnetic basement using the Tilt-Depth method from the best available magnetic anomaly grids covering the continental USA and Australia. For the USA, the Tilt-Depth estimates were compared with sediment thicknesses based on drilling data and show a correlation of 0.86 between the datasets. If random data were used then the correlation value goes to virtually zero. There is little to no lateral offset of the depth of basinal features although there is a tendency for the Tilt-Depth results to be slightly shallower than the drill depths. We also applied the Tilt-Depth method to a local-scale, relatively high-resolution aeromagnetic survey over the Olympic Peninsula of Washington State. The Tilt-Depth method successfully identified a variety of important tectonic elements known from geological mapping. Of particular interest, the Tilt-Depth method illuminated deep (3km) contacts within the non-magnetic sedimentary core of the Olympic Mountains, where magnetic anomalies are subdued and low in amplitude. For Australia, the Tilt-Depth estimates also give a good correlation with known areas of shallow basement and sedimentary basins. Our estimates of basement depth are not restricted to regional analysis but work equally well at the micro scale (basin scale) with depth estimates agreeing well with drill hole and seismic data. We focus on the eastern Officer Basin as an example of basin scale studies and find a good level of agreement between previously-derived basin models. However, our study potentially reveals depocentres not previously mapped due to the sparse distribution of well data. This example thus shows the potential additional advantage of the method in geological interpretation. The success of this study suggests that the Tilt-Depth method is useful in estimating the depth to crystalline basement when appropriate quality aeromagnetic anomaly data are used (i.e. line spacing on the order of or less than the expected depth to

  2. The 25-km Discontinuity: Implications for Lunar History.

    PubMed

    Simmons, G; Todd, T; Wang, H

    1973-10-12

    The lunar velocity profile and laboratory data on terrestrial and lunar rocks are constraints on models of lunar history. They show that shock-induced microcracks are absent from the rocks present in the moon today at depths of 25 to 60 kilometers. All possible causes of this observation are examined, and the most likely explanations are that either the rocks at depths of 25 to 60 kilometers formed after the major impacts ceased or the microcracks have annealed at temperatures of about 600 degrees C over geologically long times.

  3. Modeling Low Velocity Impacts: Predicting Crater Depth on Pluto

    NASA Astrophysics Data System (ADS)

    Bray, V. J.; Schenk, P.

    2014-12-01

    The New Horizons mission is due to fly-by the Pluto system in Summer 2015 and provides the first opportunity to image the Pluto surface in detail, allowing both the appearance and number of its crater population to be studied for the first time. Bray and Schenk (2014) combined previous cratering studies and numerical modeling of the impact process to predict crater morphology on Pluto based on current understanding of Pluto's composition, structure and surrounding impactor population. Predictions of how the low mean impact velocity (~2km/s) of the Pluto system will influence crater formation is a complex issue. Observations of secondary cratering (low velocity, high angle) and laboratory experiments of impact at low velocity are at odds regarding how velocity controls depth-diameter ratios: Observations of secondary craters show that these low velocity craters are shallower than would be expected for a hyper-velocity primary. Conversely, gas gun work has shown that relative crater depth increases as impact velocity decreases. We have investigated the influence of impact velocity further with iSALE hydrocode modeling of comet impact into Pluto. With increasing impact velocity, a projectile will produce wider and deeper craters. The depth-diameter ratio (d/D) however has a more complex progression with increasing impact velocity: impacts faster than 2km/s lead to smaller d/D ratios as impact velocity increases, in agreement with gas-gun studies. However, decreasing impact velocity from 2km/s to 300 m/s produced smaller d/D as impact velocity was decreased. This suggests that on Pluto the deepest craters would be produced by ~ 2km/s impacts, with shallower craters produced by velocities either side of this critical point. Further simulations to investigate whether this effect is connected to the sound speed of the target material are ongoing. The complex relationship between impact velocity and crater depth for impacts occurring between 300m/s and 10 km/s suggests

  4. Medium-depth chemical peels.

    PubMed

    Monheit, G D

    2001-07-01

    The combination medium-depth chemical peel (Jessner's solution +35% TCA) has been accepted as a safe, reliable, and effective method for the treatment of moderate photoaging skin. This article discusses the procedure in detail, including postoperative considerations. PMID:11599398

  5. Teaching Depth of Field Concept

    ERIC Educational Resources Information Center

    Ross, Frederick C.; Smith, Rodney J.

    1978-01-01

    This activity utilizes an overhead projector, a wax pencil, and a petri-dish to demonstrate the depth of field concept to students learning the use of the microscope. Illustrations and directions are included. (MA)

  6. The coefficient of friction of chrysotile gouge at seismogenic depths

    USGS Publications Warehouse

    Moore, Diane E.; Lockner, D.A.; Tanaka, H.; Iwata, K.

    2004-01-01

    We report new strength data for the serpentine mineral chrysotile at effective normal stresses, ??sn between 40 and 200 MPa in the temperature range 25??-280??C. Overall, the coefficient of friction, ?? (= shear stress/effective normal stress) of water-saturated chrysotile gouge increases both with increasing temperature and ??sn, but the rates vary and the temperature-related increases begin at ???100??C. As a result, a frictional strength minimum (?? = 0.1) occurs at low ??sn at about 100??C. Maximum strength (?? = 0.55) results from a combination of high normal stress and high temperature. The low-strength region is characterized by velocity strengthening and the high-strength region by velocity-weakening behavior. Thoroughly dried chrysotile has ?? = 0.7 and is velocity-weakening. The frictional properties of chrysolite can be explained in its tendency to adsorb large amounts of water that acts as a lubricant during shear. The water is progressively driven off the fiber surfaces with increasing temperature and pressure, causing chrysotile to approach its dry strength. Depth profiles for a chrysotile-lined fault constructed from these data would pass through a strength minimum at ???3 km depth, where sliding should be stable. Below that depth, strength increases rapidly as does the tendency for unstable (seismic) slip. Such a trend would not have been predicted from the room-temperature data. These results therefore illustrate the potential hazards of extrapolating room-temperature friction data to predict fault zone behavior at depth. This depth profile for chrysotile is consistent with the pattern of slip on the Hayward fault, which creeps aseismically at shallow depths but which may be locked below 5 km depth. ?? 2004 by V. H. Winston and Son, Inc. All rights reserved.

  7. Depth perception of illusory surfaces.

    PubMed

    Kogo, Naoki; Drożdżewska, Anna; Zaenen, Peter; Alp, Nihan; Wagemans, Johan

    2014-03-01

    The perception of an illusory surface, a subjectively perceived surface that is not given in the image, is one of the most intriguing phenomena in vision. It strongly influences the perception of some fundamental properties, namely, depth, lightness and contours. Recently, we suggested (1) that the context-sensitive mechanism of depth computation plays a key role in creating the illusion, (2) that the illusory lightness perception can be explained by an influence of depth perception on the lightness computation, and (3) that the perception of variations of the Kanizsa figure can be well-reproduced by implementing these principles in a model (Kogo, Strecha, et al., 2010). However, depth perception, lightness perception, contour perception, and their interactions can be influenced by various factors. It is essential to measure the differences between the variation figures in these aspects separately to further understand the mechanisms. As a first step, we report here the results of a new experimental paradigm to compare the depth perception of the Kanizsa figure and its variations. One of the illusory figures was presented side-by-side with a non-illusory variation whose stereo disparities were varied. Participants had to decide in which of these two figures the central region appeared closer. The results indicate that the depth perception of the illusory surface was indeed different in the variation figures. Furthermore, there was a non-linear interaction between the occlusion cues and stereo disparity cues. Implications of the results for the neuro-computational mechanisms are discussed.

  8. INCREASED AIRWAYS INFLAMMATION AND MODIFIED BAL CELL SURFACE PHENOTYPES IN ASTHMATICS EXPOSED TO COARSE SIZE (PM2.5-10) CONCENTRATED AMBIENT PARTICLES (CAPS)

    EPA Science Inventory

    Although associations between inhalation of PM10 and disease morbidity and mortality appear stronger for fine (PM2.5) vs coarse (PM2.5-10) or ultrafine/UF (PM<0.1) PM. In vitro studies suggest that PM2.5-10 are more potent in inducing pro-inflammatory cytokine responses from alve...

  9. Fact Sheet for KM200 Front-end Electronics

    SciTech Connect

    Ianakiev, Kiril Dimitrov; Iliev, Metodi; Swinhoe, Martyn Thomas

    2015-07-08

    The KM200 device is a versatile, configurable front-end electronics boards that can be used as a functional replacement for Canberra’s JAB-01 boards based on the Amptek A-111 hybrid chip, which continues to be the preferred choice of electronics for large number of the boards in junction boxes of multiplicity counters that process the signal from an array of 3He detectors. Unlike the A-111 chip’s fixed time constants and sensitivity range, the shaping time and sensitivity of the new KM200 can be optimized for demanding applications such as spent fuel, and thus could improve the safeguards measurements of existing systems where the A-111 or PDT electronics does not perform well.

  10. Remote (250 km) Fiber Bragg Grating Multiplexing System

    PubMed Central

    Fernandez-Vallejo, Montserrat; Rota-Rodrigo, Sergio; Lopez-Amo, Manuel

    2011-01-01

    We propose and demonstrate two ultra-long range fiber Bragg grating (FBG) sensor interrogation systems. In the first approach four FBGs are located 200 km from the monitoring station and a signal to noise ratio of 20 dB is obtained. The second improved version is able to detect the four multiplexed FBGs placed 250 km away, offering a signal to noise ratio of 6–8 dB. Consequently, this last system represents the longest range FBG sensor system reported so far that includes fiber sensor multiplexing capability. Both simple systems are based on a wavelength swept laser to scan the reflection spectra of the FBGs, and they are composed by two identical-lengths optical paths: the first one intended to launch the amplified laser signal by means of Raman amplification and the other one is employed to guide the reflection signal to the reception system. PMID:22164101

  11. Remote (250 km) fiber Bragg grating multiplexing system.

    PubMed

    Fernandez-Vallejo, Montserrat; Rota-Rodrigo, Sergio; Lopez-Amo, Manuel

    2011-01-01

    We propose and demonstrate two ultra-long range fiber Bragg grating (FBG) sensor interrogation systems. In the first approach four FBGs are located 200 km from the monitoring station and a signal to noise ratio of 20 dB is obtained. The second improved version is able to detect the four multiplexed FBGs placed 250 km away, offering a signal to noise ratio of 6-8 dB. Consequently, this last system represents the longest range FBG sensor system reported so far that includes fiber sensor multiplexing capability. Both simple systems are based on a wavelength swept laser to scan the reflection spectra of the FBGs, and they are composed by two identical-lengths optical paths: the first one intended to launch the amplified laser signal by means of Raman amplification and the other one is employed to guide the reflection signal to the reception system. PMID:22164101

  12. Real Km-synthesis via generalized Popov multipliers

    NASA Technical Reports Server (NTRS)

    Chiang, R. Y.; Safonov, M. G.

    1992-01-01

    The authors refine their H-infinity control designs presented at the 1990 and 1991 American Control Conference by introducing a new real Km-synthesis technique involving the use of generalized Popov multipliers. This multiplier technique substantially reduces, and in some cases may even eliminate altogether, the conservativeness associated with traditional Km-synthesis solutions in which all uncertainties are treated as complex, even when they arise from real parameters such as the masses and spring constants in the benchmark problem. The design results demonstrate how this approach permits a very precise analysis of the intrinsic tradeoffs between robustness, performance, and control energy requirements. Also included is an open-loop H-infinity prefilter design that makes it possible to address the command response shaping issue. The design concept has been applied to the benchmark problem no. 4 and successfully removes the initial undesired transient and cuts down the percent overshoot.

  13. (134)Cs and ¹³⁷Cs levels in a grassland, 32 km northwest of the Fukushima 1 Nuclear Power Plant, measured for two seasons after the fallout.

    PubMed

    Terashima, Ichiro; Shiyomi, Masae; Fukuda, Hiroo

    2014-01-01

    We measured the levels of radioactive caesium (RACs; ¹³⁴Cs and ¹³⁷Cs) in plants and soil in a grassland, 32 km northwest of the Fukushima 1 Nuclear Power Plant, from June 2011 to October 2012. In 2011, the highest RACs levels (¹³⁴Cs + ¹³⁷Cs) in plants and in the 0-5 cm soil layer were approximately 80 kBq per kg dry weight (DW). Forage grasses and clovers in this grassland showed similar RACs levels. On a DW basis, the levels of RACs in these plants tended to increase with increasing biomass over both years, but the absolute levels decreased in 2012. The RACs levels in the soil decreased sharply with soil depth; the RACs level in the 5-10 cm soil layer was only 3 % of that in the 0-5 cm layer. The transfer factor (ratio of radioactivity in plant parts on DW basis to that in the 0-10 cm soil layer) was 0.5 and 1.0 for the aboveground and belowground plant parts, respectively, in 2011, and these values decreased by approximately 50 % in 2012. We discuss the possible mechanisms underlying these trends, and strategies to decrease the level of RACs in plants to the permissible level for forage.

  14. Kinematic characteristics of elite men's 50 km race walking.

    PubMed

    Hanley, Brian; Bissas, Athanassios; Drake, Andrew

    2013-01-01

    Race walking is an endurance event which also requires great technical ability, particularly with respect to its two distinguishing rules. The 50 km race walk is the longest event in the athletics programme at the Olympic Games. The aims of this observational study were to identify the important kinematic variables in elite men's 50 km race walking, and to measure variation in those variables at different distances. Thirty men were analysed from video data recorded during a World Race Walking Cup competition. Video data were also recorded at four distances during the European Cup Race Walking and 12 men analysed from these data. Two camcorders (50 Hz) recorded at each race for 3D analysis. The results of this study showed that walking speed was associated with both step length (r=0.54,P=0.002) and cadence (r=0.58,P=0.001). While placing the foot further ahead of the body at heel strike was associated with greater step lengths (r=0.45,P=0.013), it was also negatively associated with cadence (r= -0.62,P<0.001). In the World Cup, knee angles ranged between 175 and 186° at initial contact and between 180 and 195° at midstance. During the European Cup, walking speed decreased significantly (F=9.35,P=0.002), mostly due to a decrease in step length between 38.5 and 48.5 km (t=8.59,P=0.014). From this study, it would appear that the key areas a 50 km race walker must develop and coordinate are step length and cadence, although it is also important to ensure legal walking technique is maintained with the onset of fatigue. PMID:23679143

  15. Organizations, Paradigms, and People: The Challenge of KM Interventions

    NASA Technical Reports Server (NTRS)

    Bailey, Teresa; Burton, Yvette

    1999-01-01

    This paper presents viewgraphs on Knowledge Management (KM) and how these interventions are put into practice by organizations and society. The topics include: 1) The Multiple Paradigm Tool; 2) Four Paradigms: tool for the Analyzing Organizations; 3) Assumptions About the Nature of Social Science; 4) Assumptions About the Nature of Society; 5) Schools of Sociological and Organizational Theory; 6) Meaning and Metaphors in the Four Paradigms; and 7) Possibilities and Conclusions.

  16. Towards Mapping the Ocean Surface Topography at 1 km Resolution

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng; Rodriquez, Ernesto

    2006-01-01

    We propose to apply the technique of synthetic aperture radar interferometry to the measurement of ocean surface topography at spatial resolution approaching 1 km. The measurement will have wide ranging applications in oceanography, hydrology, and marine geophysics. The oceanographic and related societal applications are briefly discussed in the paper. To meet the requirements for oceanographic applications, the instrument must be flown in an orbit with proper sampling of ocean tides.

  17. The lectin KM+ induces corneal epithelial wound healing in rabbits.

    PubMed

    Chahud, Fernando; Ramalho, Leandra N Z; Ramalho, Fernando S; Haddad, Antonio; Roque-Barreira, Maria C

    2009-04-01

    Neutrophil influx is essential for corneal regeneration (Gan et al. 1999). KM+, a lectin from Artocarpus integrifolia, induces neutrophil migration (Santos-de-Oliveira et al. 1994). This study aims at investigating a possible effect of KM+ on corneal regeneration in rabbits. A 6.0-mm diameter area of debridement was created on the cornea of both eyes by mechanical scraping. The experimental eyes received drops of KM+ (2.5 microg/ml) every 2 h. The control eyes received buffer. The epithelial wounded areas of the lectin-treated and untreated eyes were stained with fluorescein, photographed and measured. The animals were killed 12 h (group 1, n = 5), 24 h (group 2, n = 10) and 48 h (group 3, n = 5) after the scraping. The corneas were analysed histologically (haematoxylin and eosin and immunostaining for proliferation cell nuclear antigen, p63, vascular endothelial growth factor, c-Met and laminin). No significant differences were found at the epithelial gap between treated and control eyes in the group 1. However, the number of neutrophils in the wounded area was significantly higher in treated eyes in this group. Three control and seven treated eyes were healed completely and only rare neutrophils persisted in the corneal stroma in group 2. No morphological distinction was observed between treated and control eyes in group 3. In treated corneas of group 2, there was an increase in immunostaining of factors involved in corneal healing compared to controls. Thus, topical application of KM+ may facilitate corneal epithelial wound healing in rabbits by means of a mechanism that involves increased influx of neutrophils into the wounded area induced by the lectin.

  18. Acceleration of barium ions near 8000 km above an aurora

    NASA Technical Reports Server (NTRS)

    Stenbaek-Nielsen, H. C.; Hallinan, T. J.; Wescott, E. M.; Foeppl, H.

    1984-01-01

    A barium shaped charge, named Limerick, was released from a rocket launched from Poker Flat Research Range, Alaska, on March 30, 1982, at 1033 UT. The release took place in a small auroral breakup. The jet of ionized barium reached an altitude of 8100 km 14.5 min after release, indicating that there were no parallel electric fields below this altitude. At 8100 km the jet appeared to stop. Analysis shows that the barium at this altitude was effectively removed from the tip. It is concluded that the barium was actually accelerated upward, resulting in a large decrease in the line-of-sight density and hence the optical intensity. The parallel electric potential in the acceleration region must have been greater than 1 kV over an altitude interval of less than 200 km. The acceleration region, although presumably auroral in origin, did not seem to be related to individual auroral structures, but appeared to be a large-scale horizontal structure. The perpendicular electric field below, as deduced from the drift of the barium, was temporally and spatially very uniform and showed no variation related to individual auroral structures passing through.

  19. Contrasting estimates on the depth of magma storage zones in volcanic systems from mineral barometry and phase equilibrium experiments: a case study from Mount Merapi, Indonesia

    NASA Astrophysics Data System (ADS)

    Erdmann, Saskia; Martel, Caroline

    2015-04-01

    Mount Merapi, located in central Java, erupts on average every 5-10 years by discharging block-and-ash flows that pose local, but spatially restricted hazards. In 2010, however, the volcano erupted with a force that has been unprecedented in over 100 years. Its proximity to the metropolis of Yogyakarta with a population of >4 million makes short- and long-term eruption forecasting a task of vital importance. Critical to the appraisal of the volcano's hazard potential are tight constraints on its upper-crustal magma plumbing system and particularly on the location of its pre-eruptive reservoir. Previous petrological studies have estimated on the basis of amphibole and clinopyroxene barometry that the main magma storage zone below Merapi is located at depths of >10-15 km, while geophysical surveys have inferred significant magma storage zones at depths of ~5.5-9 km. We have carried out phase equilibrium experiments on basaltic andesite erupted in 2010, which indicate that the main pre-eruptive reservoir is located at a depth of ~7-8 km (~200 MPa). Our results thus corroborate the findings of earlier geophysical surveys and highlight the extreme uncertainty of mineral-based pressure estimates for volcanic magma systems. We point out that the commonly employed amphibole barometric calibrations of Ridolfi et al. (2010) and Ridolfi & Renzulli (2012) calculate low crystallization pressure for amphibole crystallized from felsic melt and high crystallization pressure for amphibole crystallized from mafic melt, and that the calculated pressure is thus largely unrelated to true values. Commonly employed clinopyroxene barometers (e.g., those of Nimis 1999; Putirka 2008) are also of limited use for estimating the location of crustal magma reservoirs, because the methods have large standard errors and are extremely temperature-sensitive. As a result, the calculated crystallization pressures inevitably indicate crystallization over a large range of depths, often from deep- to

  20. Effect of multivitamins on plasma homocysteine in patients with the 5,10 methylenetetrahydrofolate reductase C677T homozygous state.

    PubMed

    Dell'edera, Domenico; Tinelli, Andrea; Milazzo, Giusi Natalia; Malvasi, Antonio; Domenico, Carone; Pacella, Elena; Pierluigi, Compagnoni; Giuseppe, Tarantino; Marcello, Guido; Francesco, Lomurno; Epifania, Annunziata Anna

    2013-08-01

    The role of hyperhomocysteinemia (HHcy) as a cardiovascular risk factor remains a matter of debate, while it correlates with folates, it demonstrates inverse correlation with plasma homocysteine (Hcy) levels and vitamin B12 levels and reduces plasma Hcy levels following supplementation with multivitamins. The purpose of this study was to demonstrate that administering multivitamins at specific doses for 90 days restores normal plasma Hcy levels in women who are homozygous for the thermolabile variant of 5,10 methylenetetrahydrofolate reductase (MTHFR C677T). We enrolled 106 healthy females aged between 30 and 42 years, who were non-smokers, non-vegetarian, normotensive and who had no history of food abuse in the previous months. Only females were enrolled in order to rule out any bias due to the variation in Hcy plasma concentrations between males and females. Patient blood sampling was performed in order to determine plasma Hcy, serum folic acid and vitamin B12 levels. Furthermore, molecular characterization of the C677T polymorphism present in the MTHFR gene, was also performed. The results of this study demonstrated that supplementation with specific multivitamins restores normal plasma Hcy levels, regardless of the MTHFR genotype. Furthermore, it is unnecessary to adminster high doses of folate to reduce plasma Hcy levels, and administering high doses of folate may cause pro-inflammatory and pro-proliferative effects. PMID:23818036

  1. Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5-10 GHz frequency range.

    PubMed

    Bonetti, Stefano; Kukreja, Roopali; Chen, Zhao; Spoddig, Detlef; Ollefs, Katharina; Schöppner, Christian; Meckenstock, Ralf; Ney, Andreas; Pinto, Jude; Houanche, Richard; Frisch, Josef; Stöhr, Joachim; Dürr, Hermann A; Ohldag, Hendrik

    2015-09-01

    We present a scanning transmission x-ray microscopy setup combined with a novel microwave synchronization scheme for studying high frequency magnetization dynamics at synchrotron light sources. The sensitivity necessary to detect small changes in the magnetization on short time scales and nanometer spatial dimensions is achieved by combining the excitation mechanism with single photon counting electronics that is locked to the synchrotron operation frequency. Our instrument is capable of creating direct images of dynamical phenomena in the 5-10 GHz range, with high spatial resolution. When used together with circularly polarized x-rays, the above capabilities can be combined to study magnetic phenomena at microwave frequencies, such as ferromagnetic resonance (FMR) and spin waves. We demonstrate the capabilities of our technique by presenting phase resolved images of a ∼6 GHz nanoscale spin wave generated by a spin torque oscillator, as well as the uniform ferromagnetic precession with ∼0.1° amplitude at ∼9 GHz in a micrometer-sized cobalt strip. PMID:26429444

  2. DNA Physical Mapping via the Controlled Translocation of Single Molecules through a 5-10nm Silicon Nitride Nanopore

    NASA Astrophysics Data System (ADS)

    Stein, Derek; Reisner, Walter; Jiang, Zhijun; Hagerty, Nick; Wood, Charles; Chan, Jason

    2009-03-01

    The ability to map the binding position of sequence-specific markers, including transcription-factors, protein-nucleic acids (PNAs) or deactivated restriction enzymes, along a single DNA molecule in a nanofluidic device would be of key importance for the life-sciences. Such markers could give an indication of the active genes at particular stage in a cell's transcriptional cycle, pinpoint the location of mutations or even provide a DNA barcode that could aid in genomics applications. We have developed a setup consisting of a 5-10 nm nanopore in a 20nm thick silicon nitride film coupled to an optical tweezer setup. The translocation of DNA across the nanopore can be detected via blockades in the electrical current through the pore. By anchoring one end of the translocating DNA to an optically trapped microsphere, we hope to stretch out the molecule in the nanopore and control the translocation speed, enabling us to slowly scan across the genome and detect changes in the baseline current due to the presence of bound markers.

  3. Solvent effect on the nonlinear absorption of 5,10-A(2)B(2) meso substituted porphyrins.

    PubMed

    Zawadzka, Monika; Wang, Jun; Blau, Werner J; Senge, Mathias O

    2013-10-01

    The effect of the solvent on the nonlinear absorptive properties of two series of 5,10-A2B2 porphyrins was investigated with an open Z-scan technique in the ns time regime. The recorded responses, which varied between compounds and solvents, were fitted to a four-level model where the one-photon excited state absorption is followed by a two-photon process arising from the higher excited states. For most of the compounds the positive nonlinear absorption in toluene was stronger than that in DMF and chloroform. This was attributed to enhanced two-photon absorption in toluene. For DMF and chloroform the solvent effects were most likely to be compound specific. It was demonstrated that the high saturation intensity of two-photon absorption shifts the RSA/SA turnover into a higher fluence range, which is desirable for optical limiting applications. This saturation intensity of two-photon absorption varied between compounds and solvents. Additionally, nonlinear scattering contributed strongly to the open Z-scan responses for many compounds in chlorobenzene and chloroform-chlorobenzene solutions. This was associated with the photodegradation of chlorobenzene.

  4. A Neptune-sized transiting planet closely orbiting a 5-10-million-year-old star

    NASA Astrophysics Data System (ADS)

    David, Trevor J.

    2016-10-01

    Theories of the formation and early evolution of planetary systems postulate that planets are born in circumstellar disks, and undergo radial migration during and after dissipation of the dust and gas disk from which they formed. The precise ages of meteorites indicate that planetesimals - the building blocks of planets - are produced within the first million years of a star's life. A prominent question is: how early can one find fully formed planets like those frequently detected on short orbital periods around mature stars? Some theories suggest the in situ formation of planets close to their host stars is unlikely and the existence of such planets is evidence for large scale migration. Other theories posit that planet assembly at small orbital separations may be common. Here we report on a newly-born, transiting planet orbiting its star every 5.4 days. The planet is 50 per cent larger than Neptune, and its mass is less than 3.6 times Jupiter (at 99.7 per cent confidence), with a true mass likely to be within a factor of several of Neptune's. The 5-10 million year old star has a tenuous dust disk extending outwards from about 2 times the Earth-Sun separation, in addition to the large planet located at less than one-twentieth the Earth-Sun separation.

  5. A Neptune-sized transiting planet closely orbiting a 5-10-million-year-old star

    NASA Astrophysics Data System (ADS)

    David, Trevor J.; Hillenbrand, Lynne A.; Petigura, Erik A.; Carpenter, John M.; Crossfield, Ian J. M.; Hinkley, Sasha; Ciardi, David R.; Howard, Andrew W.; Isaacson, Howard T.; Cody, Ann Marie; Schlieder, Joshua E.; Beichman, Charles A.; Barenfeld, Scott A.

    2016-06-01

    Theories of the formation and early evolution of planetary systems postulate that planets are born in circumstellar disks, and undergo radial migration during and after dissipation of the dust and gas disk from which they formed. The precise ages of meteorites indicate that planetesimals—the building blocks of planets—are produced within the first million years of a star’s life. Fully formed planets are frequently detected on short orbital periods around mature stars. Some theories suggest that the in situ formation of planets close to their host stars is unlikely and that the existence of such planets is therefore evidence of large-scale migration. Other theories posit that planet assembly at small orbital separations may be common. Here we report a newly born, transiting planet orbiting its star with a period of 5.4 days. The planet is 50 per cent larger than Neptune, and its mass is less than 3.6 times that of Jupiter (at 99.7 per cent confidence), with a true mass likely to be similar to that of Neptune. The star is 5-10 million years old and has a tenuous dust disk extending outward from about twice the Earth-Sun separation, in addition to the fully formed planet located at less than one-twentieth of the Earth-Sun separation.

  6. Stability and prediction of physical activity in 5-, 10-, and 28-year follow-up studies among industrial employees.

    PubMed

    Kirjonen, J; Telama, R; Luukkonen, R; Kääriä, S; Kaila-Kangas, L; Leino-Arjas, P

    2006-06-01

    The aim of the study was to examine the stability of voluntary and household physical activity (PA) and to compare it with that of the use of the most common stimulants. The prospective cohort study comprised of follow-ups at 5, 10, and 28 years at baseline in 1973 in four plants of an industrial corporation in Finland. A systematic, non-proportional sample (n=902, age range 18-64 years) stratified for age, gender, and occupational status was drawn from the employees. Scores of PA were based on a questionnaire and interviews. Logistic regression models with proportional odds assumptions were counted. The 5-year stability (Spearman's rho) of PA time was 0.44 (PA intensity 0.44), the respective 10-year coefficient was 0.26 (0.32), and that in the 28-year follow-up was 0.18 (0.20). The stability of PA decreased rapidly from 1973 to 1983 and more slowly thereafter. Changes along the follow-up reflect a polarization of the distributions of PA within the sample. Age and an initially low level of activity were the strongest predictors of inactivity. The stability coefficient of smoking and alcohol consumption was twice as high as that of PA. Stimulant use was a greater factor in the individual's lifestyle than PA. PMID:16643199

  7. Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5-10 GHz frequency range

    NASA Astrophysics Data System (ADS)

    Bonetti, Stefano; Kukreja, Roopali; Chen, Zhao; Spoddig, Detlef; Ollefs, Katharina; Schöppner, Christian; Meckenstock, Ralf; Ney, Andreas; Pinto, Jude; Houanche, Richard; Frisch, Josef; Stöhr, Joachim; Dürr, Hermann A.; Ohldag, Hendrik

    2015-09-01

    We present a scanning transmission x-ray microscopy setup combined with a novel microwave synchronization scheme for studying high frequency magnetization dynamics at synchrotron light sources. The sensitivity necessary to detect small changes in the magnetization on short time scales and nanometer spatial dimensions is achieved by combining the excitation mechanism with single photon counting electronics that is locked to the synchrotron operation frequency. Our instrument is capable of creating direct images of dynamical phenomena in the 5-10 GHz range, with high spatial resolution. When used together with circularly polarized x-rays, the above capabilities can be combined to study magnetic phenomena at microwave frequencies, such as ferromagnetic resonance (FMR) and spin waves. We demonstrate the capabilities of our technique by presenting phase resolved images of a ˜6 GHz nanoscale spin wave generated by a spin torque oscillator, as well as the uniform ferromagnetic precession with ˜0.1° amplitude at ˜9 GHz in a micrometer-sized cobalt strip.

  8. In vitro cytotoxicity assessment of [5,10,15,20-tetra (4-sulfophenyl) porphyrin] on tumor and nontumor cell lines

    NASA Astrophysics Data System (ADS)

    Alexandrova, R.; Sabotinov, O.; Stoykova, Elena V.; Ion, Rodica-Mariana; Shurulinkov, Stanislav; Minchev, Georgi

    2004-06-01

    In this study we evaluate the cytotoxicity of 5,10,15,20- tetra (4-sulfophenyl) porphyrins on a tumor cell line LSCC-SF-Mc29, obtained from a transplantable chicken hepatoma induced by the myelocytomatosis virus Mc29, a timor line LSR-SF-SR, obtained from a transplantable sarcoma in rat induced by Rous sarcoma virus strain Schmidt-Ruppin and for normal mouse cell line (BALB/c-3T3-A31) and bovine kidney cell line (MDBK). The cells were exposed to irradiation from a pulsed CuBr vapor laser system at 510.6 nm and 578.2 nm at fluence rate 50 mW/cm2 and pulse frequency rate 20 kHz. The viability of cells was determined by the neutral red uptake cytotoxicity assay. The light dose-response curves and light exposures that ensure viability drop to 50 % were obtained for each cell line. The cytotoxic effect of TS4PP is most distinguished for LSCC-SF-Mc29. The bovine cell line is more vulnerable than the mouse line, especially at 510.6 nm. The 2-4 times higher viability of the normal cell lines in comparison with the tumor lines has been obtained.

  9. Routine estimate of focal depths for moderate and small earthquakes by modelling regional depth phase sPmP in eastern Canada

    NASA Astrophysics Data System (ADS)

    Ma, S.; Peci, V.; Adams, J.; McCormack, D.

    2003-04-01

    ROUTINE ESTIMATE OF FOCAL DEPTHS FOR MODERATE AND SMALL EARTHQUAKES BY MODELLING REGIONAL DEPTH PHASE sPmP IN EASTERN CANADA Shutian Ma, Veronika Peci, John Adams, and David McCormack(1) (1) National Earthquake Hazards Program, Geological Survey of Canada, 7 Observatory Crescent, Ottawa, ON, K1A 0Y3, Canada Shutian Ma (ma@seismo.nrcan.gc.ca/613-947 3520) Veronika Peci (peci@seismo.nrcan.gc.ca/613-995 7100) John Adams (adams@seismo.nrcan.gc.ca/613-995 5519) David McCormack (cormack@seismo.nrcan.gc.ca/613-992 8766) Earthquake focal depths are critical parameters for basic seismological research, seismotectonic study, seismic hazard assessment, and event discrimination. Focal depths for most earthquakes with Mw >= 4.5 can be estimated from teleseismic arrival times of P, pP and sP. For maller earthquakes, focal depths can be stimated from Pg and Sg arrival times recorded at close stations. However, for most earthquakes in eastern Canada, teleseismic signals are too weak and seismograph spacing too sparse for depth estimation. The regional phase sPmP is very sensitive to focal depth, generally well developed at epicentral distances greater than 100 km, and clearly recorded at many stations in eastern Canada for earthquakes with mN >= 2.8. We developed a procedure to estimate focal depth routinely with sPmP. We select vertical waveforms recorded at distances from about 100 to 300 km (using Geotool and SAC2000), generate synthetic waveforms (using reflectivity method) for a typical focal mechanism and for a suitable range of depths, and choose the depth at which the synthetic best matches the selected waveform. The software is easy to operate. For routine work an experienced operator can get a focal depth with waveform modelling within 10 minutes after the waveform is selected, or in a couple of minutes get a rough focal depth from sPmP and Pg or PmP arrival times without waveform modelling. We have confirmed our sPmP modelling results by two comparisons: (1) to depths

  10. Comparison of broadband mode arrivals at ranges of 3515 km and 5171 km in the North Pacific

    NASA Astrophysics Data System (ADS)

    Wage, Kathleen E.

    2003-04-01

    The Acoustic Thermometry of Ocean Climate (ATOC) provided an opportunity to observe signals propagating in the low-order modes of the ocean waveguide. Understanding the fluctuations of these mode signals is an important prerequisite to using them for tomography or other applications. In previous work, we characterized the cross-mode coherence and temporal variability of the low-order mode arrivals at 3515 km range [Wage et al., J. Acoust. Soc. Am. (in press)]. This study compares the mode arrivals for two different ranges : 3515 km and 5171 km, using data from the ATOC vertical line arrays at Hawaii and Kiritimati. We discuss the mode intensity and coherence statistics for each of the arrays and examine mean arrival time trends over the year-long deployment. Experimental results are compared to PE simulations of propagation through a realistic background environment perturbed by internal waves of varying strengths. The dependence of mode statistics on the path-dependent changes in the background sound speed and the parameters of the internal wave field is explored. [Work supported by an ONR Ocean Acoustics Young Faculty Award.] a)A. B. Baggeroer, T. G. Birdsall, C. Clark, J. A. Colosi, B. D. Cornuelle, D. Costa, B. D. Dushaw, M. A. Dzieciuch, A. M. G. Forbes, B. M. Howe, D. Menemenlis, J. A. Mercer, K. Metzger, W. H. Munk, R. C. Spindel, P. F. Worcester, and C. Wunsch.

  11. Monitoring the Depth of Anaesthesia

    PubMed Central

    Musizza, Bojan; Ribaric, Samo

    2010-01-01

    One of the current challenges in medicine is monitoring the patients’ depth of general anaesthesia (DGA). Accurate assessment of the depth of anaesthesia contributes to tailoring drug administration to the individual patient, thus preventing awareness or excessive anaesthetic depth and improving patients’ outcomes. In the past decade, there has been a significant increase in the number of studies on the development, comparison and validation of commercial devices that estimate the DGA by analyzing electrical activity of the brain (i.e., evoked potentials or brain waves). In this paper we review the most frequently used sensors and mathematical methods for monitoring the DGA, their validation in clinical practice and discuss the central question of whether these approaches can, compared to other conventional methods, reduce the risk of patient awareness during surgical procedures. PMID:22163504

  12. Flexible depth of field photography.

    PubMed

    Kuthirummal, Sujit; Nagahara, Hajime; Zhou, Changyin; Nayar, Shree K

    2011-01-01

    The range of scene depths that appear focused in an image is known as the depth of field (DOF). Conventional cameras are limited by a fundamental trade-off between depth of field and signal-to-noise ratio (SNR). For a dark scene, the aperture of the lens must be opened up to maintain SNR, which causes the DOF to reduce. Also, today's cameras have DOFs that correspond to a single slab that is perpendicular to the optical axis. In this paper, we present an imaging system that enables one to control the DOF in new and powerful ways. Our approach is to vary the position and/or orientation of the image detector during the integration time of a single photograph. Even when the detector motion is very small (tens of microns), a large range of scene depths (several meters) is captured, both in and out of focus. Our prototype camera uses a micro-actuator to translate the detector along the optical axis during image integration. Using this device, we demonstrate four applications of flexible DOF. First, we describe extended DOF where a large depth range is captured with a very wide aperture (low noise) but with nearly depth-independent defocus blur. Deconvolving a captured image with a single blur kernel gives an image with extended DOF and high SNR. Next, we show the capture of images with discontinuous DOFs. For instance, near and far objects can be imaged with sharpness, while objects in between are severely blurred. Third, we show that our camera can capture images with tilted DOFs (Scheimpflug imaging) without tilting the image detector. Finally, we demonstrate how our camera can be used to realize nonplanar DOFs. We believe flexible DOF imaging can open a new creative dimension in photography and lead to new capabilities in scientific imaging, vision, and graphics. PMID:21088319

  13. Earthquake forecasting test for Kanto district: Analysis of an earthquake catalog considering focal depth

    NASA Astrophysics Data System (ADS)

    Yokoi, S.; Tsuruoka, H.; Hirata, N.

    2013-12-01

    We started a research for constructing a 3-dimensional (3D) earthquake forecasting model for the Kanto district in Japan under the Special Project for Reducing Vulnerability for Urban Mega Earthquake Disasters. Because seismicity in this area ranges from shallower part to a depth of 80 km due to subducting Philippine Sea plate and Pacific plate, we need to study effect of earthquake depth distribution. We are developing forecasting models based on the results of 2D modeling. In the first step of the study, we defined the 3D - forecasting region in Kanto with a grid of horizontal 0.1° x 0.1° and every 10 km in a depth from 0 km to 100 km. Then, it was confirmed that RI model showed a good performance in the 3D-forecasting model compared with a 2D model which is non-divided column from 0 km to100 km in a depth. RI model (Nanjo, 2011) learned past seismicity from JMA catalog for 10 years from 1998 to 2009 to estimate probabilities of earthquakes from November 2009 to January 2010. Because we aim to improve forecasting performance of a model of a large earthquake, we need a longer period of earthquake data than current studies. In this study, we analyzed completeness magnitude (Mc) of JMA catalog from 1970 to 2007 with 3 depth ranges, 0 - 30km, 30 - 60km and 60 - 100km by the Maximum curvature method (Wiemer and Wyss, 2000) to assess a quality of the catalog considering a depth of hypocenters. This method tended to estimate Mc smaller than visual inspection method. Time sequence of the Mc from 1970 to 1997 decreased independent of a depth, which means that detection limit of the hypocenter is homogeneous in a depth, and quality of the catalog improved with a time. On the other hand, Mc from 1997 to 2007 showed heterogeneous distribution with a depth. In this presentation, we discuss how use the heterogeneous catalog to develop a 3D forecasting model in Japan. The authors thank the Japan Meteorological Agency for the earthquake catalog. This work is sponsored by the

  14. Communication between earthquake clusters separated by over 30 km supports simple volcano plumbing

    NASA Astrophysics Data System (ADS)

    Jonsdottir, K.; Jonasson, K.; Gudmundsson, M. T.; Hensch, M.; Hooper, A. J.; Holohan, E. P.; Sigmundsson, F.; Halldorsson, S. A.; Hognadottir, T.; Magnússon, E.; Pálsson, F.; Walter, T. R.; Ofeigsson, B.; Parks, M.; Roberts, M. J.; Hjorleifsdottir, V.; Cesca, S.; Guðmundsson, G.; Hreinsdottir, S.; Jarosch, A. H.; Dumont, S.; Fridriksdóttir, H. M.; Barsotti, S.; Einarsson, P.

    2015-12-01

    The subglacial Bárðarbunga volcano is composed of a large oval caldera (7x11 km) and fissures extending tens of kilometers away from the caldera along the rift zone, which marks the divergent plate boundary across Iceland. On August 16th, 2014 an intense seismic swarm started below the Bárðarbunga caldera and in the two weeks that followed a dyke migrated some 47 km laterally in the uppermost 6-10 km of the crust along the rift. The dyke propagation terminated in lava fields just north of Vatnajökull glacier, where a major (1.5 km3) six months long eruption took place. Intense earthquake activity in the caldera started in the period August 21-24 with over 70 M5 earthquakes accompanying slow caldera collapse, as verified by various geodetic measurements. The subsidence is likely due to magma withdrawal from a reservoir at depth beneath the caldera. During a five months period, October-February, the seismic activity was separated by over 30 km in two clusters; one along the caldera rims (due to piecewise caldera subsidence) and the other at the far end of the dyke (as a result of small shear movements). Here we present statistical analysis comparing the temporal behaviour of seismicity recorded in the two clusters. By comparing the earthquake rate in the dyke in temporal bins before and after caldera subsidence earthquakes to the rate away from these bins (background rate), we show that the number of dyke earthquakes was significantly higher (p <0.05) in the period 0-3 hours before a large earthquake (>M4.6) in the caldera. Increased dyke seismicity was also observed 0-3 hours following a large caldera earthquake. Elevated seismicity in the dyke before a large caldera earthquake may occur when a constriction in the dyke was reduced, followed by pressure drop in the chamber. Assuming that the large caldera earthquakes occurred when chamber pressure was lowest, the subsiding caldera piston may have caused temporary higher pressure in the dyke and thereby increased

  15. Sampling Depths, Depth Shifts, and Depth Resolutions for Bi(n)(+) Ion Analysis in Argon Gas Cluster Depth Profiles.

    PubMed

    Havelund, R; Seah, M P; Gilmore, I S

    2016-03-10

    Gas cluster sputter depth profiling is increasingly used for the spatially resolved chemical analysis and imaging of organic materials. Here, a study is reported of the sampling depth in secondary ion mass spectrometry depth profiling. It is shown that effects of the sampling depth leads to apparent shifts in depth profiles of Irganox 3114 delta layers in Irganox 1010 sputtered, in the dual beam mode, using 5 keV Ar₂₀₀₀⁺ ions and analyzed with Bi(q+), Bi₃(q+) and Bi₅(q+) ions (q = 1 or 2) with energies between 13 and 50 keV. The profiles show sharp delta layers, broadened from their intrinsic 1 nm thickness to full widths at half-maxima (fwhm's) of 8-12 nm. For different secondary ions, the centroids of the measured delta layers are shifted deeper or shallower by up to 3 nm from the position measured for the large, 564.36 Da (C₃₃H₄₆N₃O₅⁻) characteristic ion for Irganox 3114 used to define a reference position. The shifts are linear with the Bi(n)(q+) beam energy and are greatest for Bi₃(q+), slightly less for Bi₅(q+) with its wider or less deep craters, and significantly less for Bi(q+) where the sputtering yield is very low and the primary ion penetrates more deeply. The shifts increase the fwhm’s of the delta layers in a manner consistent with a linearly falling generation and escape depth distribution function (GEDDF) for the emitted secondary ions, relevant for a paraboloid shaped crater. The total depth of this GEDDF is 3.7 times the delta layer shifts. The greatest effect is for the peaks with the greatest shifts, i.e. Bi₃(q+) at the highest energy, and for the smaller fragments. It is recommended that low energies be used for the analysis beam and that carefully selected, large, secondary ion fragments are used for measuring depth distributions, or that the analysis be made in the single beam mode using the sputtering Ar cluster ions also for analysis. PMID:26883085

  16. Will women outrun men in ultra-marathon road races from 50 km to 1,000 km?

    PubMed

    Zingg, Matthias Alexander; Karner-Rezek, Klaus; Rosemann, Thomas; Knechtle, Beat; Lepers, Romuald; Rüst, Christoph Alexander

    2014-01-01

    It has been assumed that women would be able to outrun men in ultra-marathon running. The present study investigated the sex differences in running speed in ultra-marathons held worldwide from 50 km to 1,000 km. Changes in running speeds and the sex differences in running speeds in the annual fastest finishers in 50 km, 100 km, 200 km and 1,000 km events held worldwide from 1969-2012 were analysed using linear, non-linear and multi-level regression analyses. For the annual fastest and the annual ten fastest finishers, running speeds increased non-linearly in 50 km and 100 km, but not in 200 km and 1,000 km where running speeds remained unchanged for the annual fastest. The sex differences decreased non-linearly in 50 km and 100 km, but not in 200 and 1,000 km where the sex difference remained unchanged for the annual fastest. For the fastest women and men ever, the sex difference in running speed was lowest in 100 km (5.0%) and highest in 50 km (15.4%). For the ten fastest women and men ever, the sex difference was lowest in 100 km (10.0 ± 3.0%) and highest in 200 km (27.3 ± 5.7%). For both the fastest (r(2) = 0.003, p = 0.82) and the ten fastest finishers ever (r(2) = 0.34, p = 0.41) in 50 km, 100 km, 200 km and 1,000 km, we found no correlation between sex difference in performance and running speed. To summarize, the sex differences in running speeds decreased non-linearly in 50 km and 100 km but remained unchanged in 200 km and 1,000 km, and the sex differences in running speeds showed no change with increasing length of the race distance. These findings suggest that it is very unlikely that women will ever outrun men in ultra-marathons held from 50 km to 100 km.

  17. fine structure of 410km discontinuity beneath the Southern Europe

    NASA Astrophysics Data System (ADS)

    Wan, K.; Wan, X.; Ni, S.

    2005-12-01

    In the distance range of 10-14 degrees, P waves from the topside reflection off the 410km discontinuity are very sensitive to the fine structure of the discontinuity. We analyzed 49 broadband seismograms from an earthquake ( May 18, 1998) in Italy (Mw 5.8) , recorded by Orfeus and SZGRF networks. Distances between the source and the stations were from 9° to 19°, and provided a detailed look at the 410km structure. On the other hand, the azimuth of these records were in a narrow range from 334° and 356°, so the differences in azimuth may have little effects on the waveforms. From our observation, P410 phase has little change in amplitude when the distance decreases from 15° to about 11.5°. However, an abrupt termination was observed from distance 11° to 10.5°. These features cannot be explained with PREM model. We calculated several groups of models with F-K method and compared their synthetic seismograms with the observed one. These models are: 1) two-step sharp jump models, with different thickness; 2) linear models; 3) linear-sharp jump models[Tim Melbourne, Don Helmberger, Journal of Geophysical Research, 1998]; 4) models calculated from a mineralogical model[Gaherty, Wang, Geophysical research letters, 1999]; Features in the observed waveform can be well modeled with model 3 and 4 while only parts of them fitted to model 1 or 2. But when we calculated with a less detailed model, seismograms of model 4 should have more noise than model 3. In conclusion, the structure of 410km discontinuity can be considered as a linear-sharp velocity jump, which is consistent with mineralogical models.

  18. Mapping the global land surface using 1 km AVHRR data

    USGS Publications Warehouse

    Lauer, D.T.; Eidenshink, J.C.

    1998-01-01

    The scientific requirements for mapping the global land surface using 1 km advanced very high resolution radiometer (AVHRR) data have been set forth by the U.S. Global Change Research Program; the International Geosphere Biosphere Programme (IGBP); The United Nations; the National Oceanic and Atmospheric Administration (NOAA); the Committee on Earth Observations Satellites; and the National Aeronautics and Space Administration (NASA) mission to planet Earth (MTPE) program. Mapping the global land surface using 1 km AVHRR data is an international effort to acquire, archive, process, and distribute 1 km AVHRR data to meet the needs of the international science community. A network of AVHRR receiving stations, along with data recorded by NOAA, has been acquiring daily global land coverage since April 1, 1992. A data set of over 70,000 AVHRR images is archived and distributed by the United States Geological Survey (USGS) EROS Data Center, and the European Space Agency. Under the guidance of the IGBP, processing standards have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NDVI) composites. The major uses of the composites are for the study of surface vegetation condition, mapping land cover, and deriving biophysical characteristics of terrestrial ecosystems. A time-series of 54 10-day global vegetation index composites for the period of April 1, 1992 through September 1993 has been produced. The production of a time-series of 33 10-day global vegetation index composites using NOAA-14 data for the period of February 1, 1995 through December 31, 1995 is underway. The data products are available from the USGS, in cooperation with NASA's MTPE program and other international organizations.

  19. 157km BOTDA with pulse coding and image processing

    NASA Astrophysics Data System (ADS)

    Qian, Xianyang; Wang, Zinan; Wang, Song; Xue, Naitian; Sun, Wei; Zhang, Li; Zhang, Bin; Rao, Yunjiang

    2016-05-01

    A repeater-less Brillouin optical time-domain analyzer (BOTDA) with 157.68km sensing range is demonstrated, using the combination of random fiber laser Raman pumping and low-noise laser-diode-Raman pumping. With optical pulse coding (OPC) and Non Local Means (NLM) image processing, temperature sensing with +/-0.70°C uncertainty and 8m spatial resolution is experimentally demonstrated. The image processing approach has been proved to be compatible with OPC, and it further increases the figure-of-merit (FoM) of the system by 57%.

  20. The relational database system of KM3NeT

    NASA Astrophysics Data System (ADS)

    Albert, Arnauld; Bozza, Cristiano

    2016-04-01

    The KM3NeT Collaboration is building a new generation of neutrino telescopes in the Mediterranean Sea. For these telescopes, a relational database is designed and implemented for several purposes, such as the centralised management of accounts, the storage of all documentation about components and the status of the detector and information about slow control and calibration data. It also contains information useful during the construction and the data acquisition phases. Highlights in the database schema, storage and management are discussed along with design choices that have impact on performances. In most cases, the database is not accessed directly by applications, but via a custom designed Web application server.

  1. An evaluation of the global 1-km AVHRR land dataset

    USGS Publications Warehouse

    Teillet, P.M.; El Saleous, N.; Hansen, M.C.; Eidenshink, Jeffery C.; Justice, C.O.; Townshend, J.R.G.

    2000-01-01

    This paper summarizes the steps taken in the generation of the global 1-km AVHRR land dataset, and it documents an evaluation of the data product with respect to the original specifications and its usefulness in research and applications to date. The evaluation addresses data characterization, processing, compositing and handling issues. Examples of the main scientific outputs are presented and options for improved processing are outlined and prioritized. The dataset has made a significant contribution, and a strong recommendation is made for its reprocessing and continuation to produce a long-term record for global change research.

  2. Seismicity and fault plane solutions of intermediate depth earthquakes in the Pamir-Hindu Kush Region

    NASA Astrophysics Data System (ADS)

    Roecker, S. W.; Soboleva, O. V.; Nersesov, I. L.; Lukk, A. A.; Hatzfeld, D.; Chatelain, J. L.; Molnar, P.

    1980-03-01

    Relocations of earthquakes, recorded by a local network of stations in Afghanistan and Tadjikistan in 1966 and 1967, indicate a narrow seismic zone (width ≲30 km) dipping steeply into the mantle to a depth of 300 km beneath the Pamir and Hindu Kush ranges. Very low seismicity was observed at depths less than about 70 km, the approximate depth of the Moho. Clear gaps in activity exist also within the zone of intermediate depth seismicity. One gap, about 50 km wide near 37°N and at depths greater than 100 km, separates a steeply northward dipping zone to the southwest from a steeply southeastward dipping zone to the northeast. This gap probably marks either a tear in the downgoing slab or a gap between two oppositely dipping slabs. Fault plane solutions, determined by Soboleva for events between 1960 and 1967, generally show steeply plunging T axes approximately within the planar seismic zone. They therefore are grossly similar to those at island arcs where no deep earthquakes occur and presumably result from gravitational body forces acting on a relatively dense slab of lithosphere. At the same time there is a very large variation in the fault plane solutions, much larger than is common at island arcs. Appendix is available with entire article on microfiche. Order from the American Geophysical Union, 2000 Florida Ave., N.W., Washington, DC 20009. Document J80-003; $1.00. Payment must accompany order.

  3. Retrieving groundwater depth in the lower reaches of Tarim River by NDVI

    NASA Astrophysics Data System (ADS)

    Shen, Qi; Chen, Yaning; Xu, Jianhua; Zhang, Yan

    2008-10-01

    The changes of the coverage of vegetation and groundwater depth during the period of ecological construction and environmental protection are the most important two indicators of the level of success in ecological water transportation project in lower reaches of Tarim River.In this study, a new way to predict the groundwater depth in the arid regions has been presented. The spatial and temporal change of vegetation states in lower reaches of Tarim River under the ecological water transpiration have been discussed by using NDVI data derived from SPOT VEGETATION (VGT) NDVI S10 time sequence image data for the year 1999, 2003 and 2006. It is found that the groundwater depth played a dominant role in determining vegetation growth status in the lower reaches of the Tarim River. After the ecological water transportation, the vegetation has been restored in both sides of the watercourse stretching to Taitema Lake, which extend to 3 km in Akedun section, but decline along the stream flow as 1km in Kaogan section. However the area, which is 3km to 15km away from watercourse, has not been influenced obviously. And the area far away (excess 15km) has no influence. Statistic analysis shows that the groundwater depth has negative relationship with NDVI. And the groundwater depth in lower reaches of Tarim River has been successfully inversed through the statistic method; the simulation precision is 75%.

  4. Analysis of sex differences in open-water ultra-distance swimming performances in the FINA World Cup races in 5 km, 10 km and 25 km from 2000 to 2012

    PubMed Central

    2014-01-01

    Background The present study investigated the changes in swimming speeds and sex differences for elite male and female swimmers competing in 5 km, 10 km and 25 km open-water FINA World Cup races held between 2000 and 2012. Methods The changes in swimming speeds and sex differences across years were analysed using linear, non-linear, and multi-level regression analyses for the annual fastest and the annual ten fastest competitors. Results For the annual fastest, swimming speed remained stable for men and women in 5 km (5.50 ± 0.21 and 5.08 ± 0.19 km/h, respectively), in 10 km (5.38 ± 0.21 and 5.05 ± 0.26 km/h, respectively) and in 25 km (5.03 ± 0.32 and 4.58 ± 0.27 km/h, respectively). In the annual ten fastest, swimming speed remained constant in 5 km in women (5.02 ± 0.19 km/h) but decreased significantly and linearly in men from 5.42 ± 0.03 km/h to 5.39 ± 0.02 km/h. In 10 km, swimming speed increased significantly and linearly in women from 4.75 ± 0.01 km/h to 5.74 ± 0.01 km/h but remained stable in men at 5.36 ± 0.21 km/h. In 25 km, swimming speed decreased significantly and linearly in women from 4.60 ± 0.06 km/h to 4.44 ± 0.08 km/h but remained unchanged at 4.93 ± 0.34 km/h in men. For the annual fastest, the sex difference in swimming speed remained unchanged in 5 km (7.6 ± 3.0%), 10 km (6.1 ± 2.5%) and 25 km (9.0 ± 3.7%). For the annual ten fastest, the sex difference remained stable in 5 km at 7.6 ± 0.6%, decreased significantly and linearly in 10 km from 7.7 ± 0.7% to 1.2 ± 0.3% and increased significantly and linearly from 4.7 ± 1.4% to 9.6 ± 1.5% in 25 km. Conclusions To summarize, elite female open-water ultra-distance swimmers improved in 10 km but impaired in 25 km leading to a linear decrease in sex difference in 10 km and a linear increase in sex difference in 25 km. The linear changes in sex differences

  5. Small fatigue cracks; Proceedings of the Second International Conference/Workshop, Santa Barbara, CA, Jan. 5-10, 1986

    SciTech Connect

    Ritchie, R.O.; Lankford, J.

    1986-01-01

    Topics discussed in this volume include crack initiation and stage I growth, microstructure effects, crack closure, environment effects, the role of notches, analytical modeling, fracture mechanics characterization, experimental techniques, and engineering applications. Papers are presented on fatigue crack initiation along slip bands, the effect of microplastic surface deformation on the growth of small cracks, short fatigue crack behavior in relation to three-dimensional aspects and the crack closure effect, the influence of crack depth on crack electrochemistry and fatigue crack growth, and nondamaging notches in fatigue. Consideration is also given to models of small fatigue cracks, short crack theory, assessment of the growth of small flaws from residual strength data, the relevance of short crack behavior to the integrity of major rotating aero engine components, and the relevance of short fatigue crack growth data to the durability and damage tolerance analyses of aircraft.

  6. Depth dependent multiple logging system

    SciTech Connect

    Howells, A. P. S.; Angehrn, J. A.; Dienglewicz, A. M.; Viswanathan, R.

    1985-12-03

    An improved well logging technique is provided for more accurately deriving and correlating a plurality of measurements made during a single traversal of a logging instrument through subsurface formations. In one exemplary embodiment, methods and apparatus are provided for deriving a more accurate and precise measurement of depth at which real-time logging measurements are made, and in particular for correcting anomalies occurring in the depth indication from cable stretch, yo-yo of the sonde in the borehole and the like. The more accurate and precise depth measurement is then utilized for generating well logging measurements on a depth-dependent basis, deriving at least some of such measurements in digital form and alternately transmitting to the surface digital and analog representations of such measurements. Furthermore, methods and apparatus are provided for deriving measurements of subsurface earth formation from a plurality of logging instruments combined in a single tool, wherein such measurements are made during a single pass through a borehole with the resultant measurement data correlatively merged, recorded and displayed.

  7. Rotating drum variable depth sampler

    SciTech Connect

    Nance, Thomas A.; Steeper, Timothy J.

    2008-07-01

    A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

  8. Perceived depth from shading boundaries.

    PubMed

    Kim, Juno; Anstis, Stuart

    2016-01-01

    Shading is well known to provide information the visual system uses to recover the three-dimensional shape of objects. We examined conditions under which patterns in shading promote the experience of a change in depth at contour boundaries, rather than a change in reflectance. In Experiment 1, we used image manipulation to illuminate different regions of a smooth surface from different directions. This manipulation imposed local differences in shading direction across edge contours (delta shading). We found that increasing the angle of delta shading, from 0° to 180°, monotonically increased perceived depth across the edge. Experiment 2 found that the perceptual splitting of shading into separate foreground and background surfaces depended on an assumed light source from above prior. Image regions perceived as foreground structures in upright images appeared farther in depth when the same images were inverted. We also found that the experienced break in surface continuity could promote the experience of amodal completion of colored contours that were ambiguous as to their depth order (Experiment 3). These findings suggest that the visual system can identify occlusion relationships based on monocular variations in local shading direction, but interprets this information according to a light source from above prior of midlevel visual processing.

  9. Pursuing the Depths of Knowledge

    ERIC Educational Resources Information Center

    Boyles, Nancy

    2016-01-01

    Today's state literacy standards and assessments demand deeper levels of knowledge from students. But many teachers ask, "What does depth of knowledge look like on these new, more rigorous assessments? How do we prepare students for this kind of thinking?" In this article, Nancy Boyles uses a sampling of questions from the PARCC and SBAC…

  10. Perceived depth from shading boundaries.

    PubMed

    Kim, Juno; Anstis, Stuart

    2016-01-01

    Shading is well known to provide information the visual system uses to recover the three-dimensional shape of objects. We examined conditions under which patterns in shading promote the experience of a change in depth at contour boundaries, rather than a change in reflectance. In Experiment 1, we used image manipulation to illuminate different regions of a smooth surface from different directions. This manipulation imposed local differences in shading direction across edge contours (delta shading). We found that increasing the angle of delta shading, from 0° to 180°, monotonically increased perceived depth across the edge. Experiment 2 found that the perceptual splitting of shading into separate foreground and background surfaces depended on an assumed light source from above prior. Image regions perceived as foreground structures in upright images appeared farther in depth when the same images were inverted. We also found that the experienced break in surface continuity could promote the experience of amodal completion of colored contours that were ambiguous as to their depth order (Experiment 3). These findings suggest that the visual system can identify occlusion relationships based on monocular variations in local shading direction, but interprets this information according to a light source from above prior of midlevel visual processing. PMID:27271807

  11. Quantum crytography over 14km of installed optical fiber

    SciTech Connect

    Hughes, R.J.; Luther, G.G.; Morgan, G.L.; Simmons, C.

    1995-09-01

    We have made the first demonstration that low error rate quantum cryptography over long distances (14km) of installed optical fiber in a real-world environment, subject to uncontrolled temperature and mechanical influences, representing an important new step towards incorporation of quantum cryptography into existing information security systems. We also point out that the high visibility single-photon interference in our experiment allows us to infer a test of the superposition principle of quantum mechanics: a photon reaching the detector has traveled over 14km of optical fiber in a wavepacket comprising a coherent superposition of two components that are spatially separated by about 2m. In principle, there are decoherence processes (or even possible modifications of quantum mechanics) that could cause the photon`s wavefunction to collapse into one component or the other during propagation, leading to a reduction in visibility. However, our results are consistent with no such loss of quantum coherence during the 67-{mu}s propagation time.

  12. Infrared emission from the atmosphere above 200 km

    NASA Technical Reports Server (NTRS)

    Simpson, J. P.

    1976-01-01

    The infrared radiation over the range from 4 to 1000 microns from atoms and molecules in the earth's atmosphere, between 200 and 400 km, was calculated. Only zenith lines of sight were considered. The excitation of the atoms and molecules is due to collisions with other molecules and to absorption of radiation from the earth and sun. In some cases, the abundances of the molecules had to be estimated. The most important lines are the forbidden lines from atomic oxygen at 63.1 and 147 micron, and the vibration-rotation band of nitric oxide at 5.3 micron. These lines can have intensities as high as a few times 0.001 ergs/sq cm/sec/steradian at 200 km altitude. In addition, the vibration-rotation bands of NO(+) at 4.3 micron and CO at 4.7 micron and the pure rotation lines of NO and NO(+) could be detected by infrared telescopes in space.

  13. KM3NeT/ORCA status and plans

    NASA Astrophysics Data System (ADS)

    Samtleben, Dorothea F. E.

    2016-04-01

    Neutrinos created in interactions of cosmic rays with the atmosphere can serve as a powerful tool to unveil the neutrino mass hierarchy (NMH). At low energies, around a few GeV, matter effects from the transition through the Earth are expected to imprint a distinct but also subtle signature on the oscillation pattern, specific to the ordering of the neutrino masses. KM3NeT/ORCA (Oscillations Research with Cosmics in the Abyss), a densely instrumented building block of the upcoming KM3NeT neutrino telescope, will be designated to measuring this signature in the Mediterranean Sea. Using detailed simulations the sensitivity towards this signature has been evaluated. The multi-PMT detectors allow in the water for an accurate reconstruction of GeV neutrino event signatures and distinction of neutrino flavours. For the determination of the mass hierarchy a median significance of 2-6σ has been estimated for three years of data taking, depending on the actual hierarchy and the oscillation parameters. At the same time the values of several oscillation parameters like θ23 will be determined to unprecedented precision.

  14. Atomic oxygen between 80 and 120 km - Evidence for a latitudinal variation in vertical transport near the mesopause

    NASA Technical Reports Server (NTRS)

    Wasser, B.; Donahue, T. M.

    1979-01-01

    Analysis of the OGO 6 OI green line nightglow photometer experiment has been carried out for eight cases when the alignment of the spacecraft was such that local emission rates could be determined below the altitude of maximum emission and down to about 80 km. The results obtained show that the vertical gradient of the emission rate between 95 and 80 km alternates between regions of very rapid variation and very slow variation spaced on a scale of 5-10 deg of latitude. Maps showing isoemissivity contours and isodensity contours for atomic oxygen concentration in vertical meridional planes are presented. The densities are computed under three assumptions concerning excitation mechanisms. Comparisons of the vertical variations of oxygen density with the results of a time dependent theory suggest the regions of strong downward transport alternate in latitude with regions of weak transport near 90 km. In the first case, conversion of O to O3 at night appears to be overwhelmed by downward transport of O.

  15. Hybrid fine scale climatology and microphysics of in-cloud icing: From 32 km reanalysis to 5 km mesoscale modeling

    NASA Astrophysics Data System (ADS)

    Lamraoui, Fayçal; Benoit, Robert; Perron, Jean; Fortin, Guy; Masson, Christian

    2015-03-01

    In-cloud icing can impose safety concerns and economic challenges for various industries. Icing climate representations proved beneficial for optimal designs and careful planning. The current study investigates in-cloud icing, its related cloud microphysics and introduces a 15-year time period climatology of icing events. The model was initially driven by reanalysis data from North American Regional Reanalysis and downscaled through a two-level nesting of 10 km and 5 km, using a limited-area version of the Global Environment Multiscale Model of the Canadian Meteorological Center. In addition, a hybrid approach is used to reduce time consuming calculations. The simulation realized exclusively on significant icing days, was combined with non-significant icing days as represented by data from NARR. A proof of concept is presented here for a 1000 km area around Gaspé during January for those 15 years. An increase in the number and intensity of icing events has been identified during the last 15 years. From GEM-LAM simulations and within the atmospheric layer between 10 m and 200 m AGL, supercooled liquid water contents indicated a maximum of 0.4 g m- 3, and 50% of the values are less than 0.05 g m- 3. All values of median volume diameters (MVD) are approximately capped by 70 μm and the typical values are around 15 μm. Supercooled Large Droplets represent approximately 5%. The vertical profile of icing climatology demonstrates a steady duration of icing events until the level of 60 m. The altitudes of 60 m and 100 m indicate substantial icing intensification toward higher elevations. GEM-LAM demonstrated a substantial improvement in the calculation of in-cloud icing, reducing significantly the challenge posed by complex terrains.

  16. Measurements of laser phase fluctuations induced by atmospheric turbulence over 2 km and 17.5 km distances.

    PubMed

    Ridley, Kevin D

    2011-09-10

    A laser heterodyne system was used to measure the phase fluctuations imposed on a 1.5 μm wavelength laser beam when double-passed over long atmospheric paths. Two distances were used: 2 and 17.5 km. Results are given for intensity scintillation, phase fluctuation time series and spectra, and phase structure function. The results are found to agree well with theory: the spectrum of phase fluctuations follows the 8/3 power law predicted for Kolmogorov turbulence over 3 orders of magnitude in frequency. The methods reported here could be used to investigate large-scale temperature variations in the atmosphere. PMID:21946989

  17. The 5-10 keV AGN luminosity function at 0.01 < z < 4.0

    NASA Astrophysics Data System (ADS)

    Fotopoulou, S.; Buchner, J.; Georgantopoulos, I.; Hasinger, G.; Salvato, M.; Georgakakis, A.; Cappelluti, N.; Ranalli, P.; Hsu, L. T.; Brusa, M.; Comastri, A.; Miyaji, T.; Nandra, K.; Aird, J.; Paltani, S.

    2016-03-01

    The active galactic nuclei (AGN) X-ray luminosity function traces actively accreting supermassive black holes and is essential for the study of the properties of the AGN population, black hole evolution, and galaxy-black hole coevolution. Up to now, the AGN luminosity function has been estimated several times in soft (0.5-2 keV) and hard X-rays (2-10 keV). AGN selection in these energy ranges often suffers from identification and redshift incompleteness and, at the same time, photoelectric absorption can obscure a significant amount of the X-ray radiation. We estimate the evolution of the luminosity function in the 5-10 keV band, where we effectively avoid the absorbed part of the spectrum, rendering absorption corrections unnecessary up to NH ~ 1023 cm-2. Our dataset is a compilation of six wide, and deep fields: MAXI, HBSS, XMM-COSMOS, Lockman Hole, XMM-CDFS, AEGIS-XD, Chandra-COSMOS, and Chandra-CDFS. This extensive sample of ~1110 AGN (0.01 < z < 4.0, 41 < log Lx < 46) is 98% redshift complete with 68% spectroscopic redshifts. For sources lacking a spectroscopic redshift estimation we use the probability distribution function of photometric redshift estimation specifically tuned for AGN, and a flat probability distribution function for sources with no redshift information. We use Bayesian analysis to select the best parametric model from simple pure luminosity and pure density evolution to more complicated luminosity and density evolution and luminosity-dependent density evolution (LDDE). We estimate the model parameters that describe best our dataset separately for each survey and for the combined sample. We show that, according to Bayesian model selection, the preferred model for our dataset is the LDDE. Our estimation of the AGN luminosity function does not require any assumption on the AGN absorption and is in good agreement with previous works in the 2-10 keV energy band based on X-ray hardness ratios to model the absorption in AGN up to redshift three

  18. Variation of curve number with storm depth

    NASA Astrophysics Data System (ADS)

    Banasik, K.; Hejduk, L.

    2012-04-01

    The NRCS Curve Number (known also as SCS-CN) method is well known as a tool in predicting flood runoff depth from small ungauged catchment. The traditional way of determination the CNs, based on soil characteristics, land use and hydrological conditions, seemed to have tendency to overpredict the floods in some cases. Over 30 year rainfall-runoff data, collected in two small (A=23.4 & 82.4 km2), lowland, agricultural catchments in Center of Poland (Banasik & Woodward 2010), were used to determine runoff Curve Number and to check a tendency of changing. The observed CN declines with increasing storm size, which according recent views of Hawkins (1993) could be classified as a standard response of watershed. The analysis concluded, that using CN value according to the procedure described in USDA-SCS Handbook one receives representative value for estimating storm runoff from high rainfall depths in the analyzes catchments. This has been confirmed by applying "asymptotic approach" for estimating the watershed curve number from the rainfall-runoff data. Furthermore, the analysis indicated that CN, estimated from mean retention parameter S of recorded events with rainfall depth higher than initial abstraction, is also approaching the theoretical CN. The observed CN, ranging from 59.8 to 97.1 and from 52.3 to 95.5, in the smaller and the larger catchment respectively, declines with increasing storm size, which has been classified as a standard response of watershed. The investigation demonstrated also changeability of the CN during a year, with much lower values during the vegetation season. Banasik K. & D.E. Woodward (2010). "Empirical determination of curve number for a small agricultural watrshed in Poland". 2nd Joint Federal Interagency Conference, Las Vegas, NV, June 27 - July 1, 2010 (http://acwi.gov/sos/pubs/2ndJFIC/Contents/10E_Banasik_ 28_02_10. pdf). Hawkins R. H. (1993). "Asymptotic determination of curve numbers from data". Journal of Irrigation and Drainage

  19. The ion population between 1300 km and 230000 km in the coma of comet P/Halley

    NASA Technical Reports Server (NTRS)

    Altwegg, K.; Balsiger, H.; Geiss, J.; Goldstein, R.; Ip, W. -H.; Meier, A.; Neugebauer, M.; Rosenbauer, H.; Shelley, E.

    1993-01-01

    During the encounter of the spacecraft Giotto with Comet Halley the two sensors of the ion mass spectrometer (IMS), high energy range spectrometer (HERS) and high intensity spectrometer (HIS), measured the mass and the three-dimensional velocity distributions of cometary ions. HIS looked mainly at the cold, slow part of the distribution close to the nucleus, HERS at the more energetic pick-up ions further out. After a thorough recalibration of the HIS flight spare unit and an extensive data analysis we present here continuous ion density-, composition-, velocity-, and temperature profiles for the water group ion (mass range 16-19 amu/e) along Giotto's inbound trajectory from 230,000 to 1300 km from the comet nucleus. The two sensors are in very good agreement in the region where their measurements overlap thus giving an excellent data base for the discussion of theoretical comet models. The most prominent feature where models and observations disagree is the so called pile up region between 8000 and 15,000 km from the nucleus.

  20. Wintertime density perturbations near 50 km in relation to latitude

    NASA Technical Reports Server (NTRS)

    Quiroz, R. S.

    1977-01-01

    Standard and reference atmospheres which depict the horizontal distribution of air density in the stratosphere and mesosphere are not realistic in that they do not provide information on the large departures from standard that may occur during a given month, nor on the time- and space-scales of atmospheric perturbations responsible for these departures. In the present paper, it is shown how this information can be obtained from a special analysis of satellite radiance measurements. Plots of the mean zonal radiance, obtained with the VTPR instrument, and the corresponding 50-km density show not only the expected strong poleward gradient of density, but also a strong density surge from late December to early January, affecting all latitudes.

  1. Transport System for Delivery Tourists At Altitude 140 km

    NASA Technical Reports Server (NTRS)

    Bolonkin, Alexander

    2002-01-01

    The author offers a new method and installation for flight in space. This method uses the centrifugal force of a rotating circular cable that provides a means for the launch of a payload into outer space, to keep the fixed space stations at high altitudes (up to 200 km). The method may also be useful for landing to space bodies, for launching of the space ships (crafts), and for moving and accelerating other artificial apparatuses. The offered installation may be used as a propulsion system for space ships and/or probes. This system uses the material of any space body (i.e. stones) for acceleration and change of the space vehicle trajectory. The suggested system may be also used as a high capacity energy accumulator.

  2. Estimating worldwide solar radiation resources on a 40km grid

    SciTech Connect

    Maxwell, E.L.; George, R.L.; Brady, E.H.

    1996-11-01

    During 1995, the National Renewable Energy Laboratory (NREL), initiated the Data Grid Task under the auspices of DOE`s Resource Assessment Program. A data grid is a framework of uniformly spaced locations (grid points) for which data are available. Estimates of monthly averages of direct normal, diffuse horizontal, and global horizontal daily-total solar radiation energy (kWh/m{sup 2}) are being made for each point on a grid covering the US, Mexico, the Caribbean, and southern Canada. The grid points are separated by approximately 40 km. Using interpolation methods, the digital data grid can be used to estimate solar resources at any location. The most encouraging result to date has been the location of sources providing worldwide data for most of the input parameters required for modeling daily total solar radiation. This is a multiyear task expected to continue through the rest of this century.

  3. Readout and data acquisition for KM3NeT

    NASA Astrophysics Data System (ADS)

    Belias, Anastasios; Manolopoulos, Konstantinos

    2013-05-01

    In the KM3NeT neutrino telescope design the readout concept is based on a point-to-point network connecting tenthousands of optical modules in the deep sea through a photonic network with the shore station. The time-over-threshold data from each Photo Multiplier Tube (PMT) of each optical module will be send to shore over fibres using dedicated wavelengths. Nanosecond timing accuracy will be schieved using a clock signal embedded in the data stream and measuring the roundtrip time from the shore to each optical module individually. The DAQ software architecture based on the Internet Communications Engine (ICE) will provide a common and uniform software framework for the control of each optical module and the data acquisition of the whole neutrino telescope.

  4. The Crust and Mantle Relationships Beneath Central and Southern Iberian Peninsula constrained by a 550 km long multiseismic transect

    NASA Astrophysics Data System (ADS)

    Ehsan, Siddique Akhtar; Carbonell, Ramon; Simancas, Jose Fernando; Martinez Poyatos, David; Azor, Antonio; Ayarza, Puy; Storti, Fabrizio

    2013-04-01

    A composite lithospheric cross section which is composed by data from controlled source multiseismic experiments strongly constrains the lithospheric structure of southwestern Iberia. The data includes coincident normal incidence and wide-angle profiles along an, approximately, 550 km long transect. This transect goes across, from North-to-South, the major tectonic zones that build up Southwestern part of the Iberian Peninsula (the Central Iberian Zone -CIZ-, the Ossa-Morena Zone -OMZ- and the South Portuguese Zone -SPZ-). The knowledge provided by these datasets constitutes the base to develop multidisciplinary models of the lithosphere. The multichannel deep seismic high resolution (60-90 fold) profiles, IBERSEIS & ALCUDIA were acquired in summer 2001 and 2007 are about 300 and 250 km long respectively. The transects image 20 s (TWTT), about 70 km depth. To address the crust and upper mantle structural relationships a reassessment of the normal incidence seismic reflection transect ALCUDIA has been carried out. We revised the key processing steps and applied advance analysis on the ALCUDIA transect with the aim to improve the signal to noise ratio especially in the deep parts and to produce a depth migrated image. The velocity model generated through wide-angle seismic survey (2003) was used to convert IBERSEIS time migrated stack image into depth. The new data processing flow provide better structural constraints on the shallow and deep structures as the current images reveal indentation features which strongly suggest horizontal tectonics. The ALCUDIA transect shows slightly less reflective upper crust about 13 km thick decoupled from the comparatively reflective lower crust. The reflectivity of the lower crust is continuous, high amplitude, horizontal and parallel though evidences of deformation are present as flat-ramp-flat geometry on the northeastern portion and a "Crocodile structure" wedging into the upper mantle on the southwestern portion of the ALCUDIA

  5. Changes in single skinfold thickness in 100 km ultramarathoners

    PubMed Central

    Knechtle, Beat; Baumgartner, Sabrina; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas; Bescós, Raúl

    2012-01-01

    Background Changes in single skinfold thickness and body fat have been investigated in ultraswimmers and ultracyclists, but not in ultrarunners. The present study investigated the changes in single skinfold thickness during a 100 km ultramarathon. Methods Firstly, we investigated associations between prerace preparation and prerace body composition and, secondly, changes in single skinfold thickness during a 100 km ultramarathon in 219 male ultramarathoners. Changes in fat mass and skeletal muscle were estimated using anthropometric methods. Results Kilometers run weekly prerace and running speed during training were negatively associated with all skinfold thicknesses (P < 0.05) except for the front thigh skinfold. During the race, skinfold thickness at the pectoral (−0.1%), suprailiac (−1.8%), and calf (−0.8%) sites decreased (P < 0.05). The subjects lost 1.9 ± 1.4 kg of body mass (P < 0.001), 0.7 ± 1.0 kg of estimated skeletal muscle mass (P < 0.001), and 0.2 ± 1.3 kg of estimated fat mass (P < 0.05). The decrease in body mass was positively related to the decrease in both estimated skeletal muscle mass (r = 0.21, P = 0.0017) and estimated fat mass (r = 0.41, P < 0.0001). Conclusion Firstly, prerace fat mass and prerace skinfold thickness were associated with both volume and speed in running training. Secondly, during the ultramarathon, skinfold thickness decreased at the pectoral, suprailiac, and calf sites, but not at the thigh site. Percent decreases in skinfold thickness for ultrarunners was lower than the percent decreases in skinfold thickness reported for ultraswimmers and ultracyclists. PMID:24198597

  6. Constraining density and velocity jumps across the 410 km discontinuity

    NASA Astrophysics Data System (ADS)

    Saki, Morvarid; Thomas, Christine; Cobden, Laura; Abreu, Rafael

    2016-04-01

    We investigate the velocity and density structure of the olivine-to-wadsleyite transition using polarities of precursor arrivals to PP seismic waves that reflect off the 410 km discontinuity beneath the Northern Atlantic. Numerous source-receiver combinations have been used in order to collect a dataset of reflection points beneath our investigation area. We analyzed over 1700 seismograms from Mw > 5.8 using array seismology methods to enhance the signal to noise ratio. For each event the polarity of the PP phase is compared to polarity of the precursor signal and we find several events where the polarity of the precursors are opposite to that of PP. There does not seem to be any dependency of the observed polarities on the propagation direction of the seismic waves but interestingly there seems to be a dependency on the distance between source and receiver. The events with epicentral distances greater than 119 degrees mostly show opposite polarities, while for those with smaller epicentral distances the same polarity of the main phase and precursor signal is dominant. Using Zeoppritz equations, we analyzed more than 64 million combinations of density, compressional and shear wave velocities for both layers, above and below the 410 km discontinuity in order to find the best combination of those parameters that can explain the observations. The results are indicating combinations of density, P and S wave velocity exhibiting a smaller contrast compared to those from the pyrolite model (the density jump, however is still positive to provide physically meaningful results). The calculated reductions in both compressional and shear wave velocities go up to 13% but mostly fall within the range of less than 7- 8%. We interpret this reduction in elastic properties and seismic velocity of minerals as the effect of a higher than normal content of water of wadsleyite in this region, while we can exclude a reduction in iron.

  7. The Moho depth map of the European Plate

    NASA Astrophysics Data System (ADS)

    Grad, Marek; Tiira, Timo

    2009-01-01

    The European Plate has a 4.5 Gy long and complex tectonic history. This is reflected in the present-day large-scale crustal structures. A new digital Moho depth map is compiled from more than 250 data sets of individual seismic profiles, 3-D models obtained by body and surface waves, receiver function results and maps of seismic and/or gravity data compilations. We have compiled the first digital, high-resolution map of the Moho depth for the whole European Plate, extending from the mid-Atlantic ridge in the west to the Ural Mountains in the east, and from the Mediterranean Sea in the south to the Barents Sea and Spitsbergen in the Arctic in the north. In general, three large domains within the European Plate crust are visible. The oldest Archean and Proterozoic crust has a thickness of 40-60 km, the continental Variscan and Alpine crust has a thickness of 20-40 km, and the youngest oceanic Atlantic crust has a thickness of 10-20 km.

  8. Seismic evidence for volatiles at large depth in the Earth

    NASA Technical Reports Server (NTRS)

    Nolet, Guust

    1994-01-01

    High resolution tomographic images that have been obtained of the subduction zones in the west Pacific do not only show very low P wave velocities above the leading edge of the slab at shallow depth, but also below 300 km. The two zones are generally, but not always, separated by a zone of normal shear velocity near 200 km depth. These findings confirm some earlier inferences from local seismic data in Japan, and similar findings of low Vp and low Q zones beneath South America. Surprisingly, such deep seismic low velocity zones have recently also been discovered beneath the locations of ancient subduction zones. A study of upper mantle shear velocity in Central Europe shows a similar distribution of low velocity zones beneath the Tornquist-Teisseyre line, the former west coast of the old continent of Baltica, and the site of the subducting Tornquist ocean in the early Palezoic. Preliminary results from a Russian-French experiment shows low P velocities below 250 km under the Urals, while an older tomographic study shows such low P velocities beneath the northern Appalachians.

  9. Hyperspectral Aerosol Optical Depths from TCAP Flights

    SciTech Connect

    Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

    2013-11-13

    4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the world’s first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STAR’s spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

  10. The distribution of earthquakes with depth and stress in subducting slabs

    NASA Technical Reports Server (NTRS)

    Vassiliou, M. S.; Hager, B. H.; Raefsky, A.

    1984-01-01

    The global variation of Benioff zone seismicity with depth and the orientation of stress axes of deep and intermediate earthquakes is explained using numerical models of subducting slabs. Models that match the seismicity and stress require a barrier to flow at the 670 km seismic discontinuity. The barrier may be a viscosity increase of at least an order of magnitude or a chemical discontinuity. Instantaneous flow is subparallel to the slabs for models with a viscosity increase but contorted for models with a chemical barrier. Log N (number of earthquakes) decreases linearly to 250-300 km depth and increases thereafter. Stress magnitude in the models shows the same pattern, in accord with experiments showing N proportional to e(k-sigma), with k a constant and sigma the stress magnitude. The models predict downdip compression in the slabs at depths below 300-400 km, as observed for earthquake stress axes.

  11. Explosion depths for phreatomagmatic eruptions

    NASA Astrophysics Data System (ADS)

    Valentine, Greg A.; Graettinger, Alison H.; Sonder, Ingo

    2014-05-01

    Subsurface phreatomagmatic explosions can result from the interaction of ascending magma with groundwater. Experiments over a wide range of energies show that for a given energy there is a depth below which an explosion will be contained within the subsurface (not erupt), and there is a corresponding shallower depth that will optimize ejecta dispersal. We combine these relationships with constraints on the energies of phreatomagmatic explosions at maar-diatreme volcanoes and show that most eruptions are likely sourced by explosions in the uppermost ~200 m, and even shallower ones (<100 m) are likely to dominate deposition onto tephra rings. Most explosions below ~200 m will not erupt but contribute to formation of, and to the vertical mixing of materials within, a diatreme (vent structure), with only rare very high energy explosions between ~200 and 500 m erupting. Similar constraints likely apply at other volcanoes that experience phreatomagmatic explosions.

  12. Ultrasonic material hardness depth measurement

    DOEpatents

    Good, Morris S.; Schuster, George J.; Skorpik, James R.

    1997-01-01

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

  13. Photon counting compressive depth mapping.

    PubMed

    Howland, Gregory A; Lum, Daniel J; Ware, Matthew R; Howell, John C

    2013-10-01

    We demonstrate a compressed sensing, photon counting lidar system based on the single-pixel camera. Our technique recovers both depth and intensity maps from a single under-sampled set of incoherent, linear projections of a scene of interest at ultra-low light levels around 0.5 picowatts. Only two-dimensional reconstructions are required to image a three-dimensional scene. We demonstrate intensity imaging and depth mapping at 256 × 256 pixel transverse resolution with acquisition times as short as 3 seconds. We also show novelty filtering, reconstructing only the difference between two instances of a scene. Finally, we acquire 32 × 32 pixel real-time video for three-dimensional object tracking at 14 frames-per-second. PMID:24104293

  14. Ultrasonic material hardness depth measurement

    DOEpatents

    Good, M.S.; Schuster, G.J.; Skorpik, J.R.

    1997-07-08

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part. 12 figs.

  15. An empirical study of the distribution of earthquakes with respect to rock type and depth

    NASA Astrophysics Data System (ADS)

    Tal, Y.; Hager, B. H.

    2013-12-01

    Whether fault slip occurs by earthquakes or by aseismic slip is thought to depend upon whether fault friction is velocity-weakening or velocity-strengthening. Because the dependence of friction behavior upon rock type and depth is not well constrained, we approach the problem empirically. We examine the distribution of earthquakes with respect to rock type and depth by comparing three-dimensional geologic models of the San Francisco Bay region and southern California to the three-dimensional seismicity distribution in these regions, which includes 99,158 earthquakes with magnitude greater than two. To account for the effects of differing volumes of rock types, the number of earthquakes within each rock type and depth interval are normalized by the corresponding volume to give a quantity we name 'earthquake density.' Depth is the primary parameter that determines the earthquake density, while whether the rock unit is sedimentary or basement rock has a secondary effect on earthquake density. This secondary effect is also depth dependent. At shallow depths, earthquake density is very small, and there is no difference between sedimentary and basement rocks. In the second depth range (3-7 km in southern California and 2-9 km in the San Francisco Bay region), the earthquake density of basement rocks is higher than that of sedimentary rocks. In the third depth range (7-9 km in southern California and 9-13 km in the San Francisco Bay region), the sedimentary rocks are more seismogenic. In the deepest depth range, the basement rocks are more seismogenic. A more detailed distribution with respect to rock type is achievable in the San Francisco Bay region, where we examine the distribution of 15,432 earthquakes with respect to the following rock units: Sedimentary, Granodiorite, Franciscan, and Gabbro. Surprisingly, we find that granodioritic rocks tend to experience fewer earthquakes than sedimentary rocks and that gabbro has the highest tendency to experience earthquakes.

  16. AusMoho: the variation of Moho depth in Australia

    NASA Astrophysics Data System (ADS)

    Kennett, B. L. N.; Salmon, M.; Saygin, E.; Group, Ausmoho Working

    2011-11-01

    Since 2004 more than 7000 km of full-crustal reflection profiles have been collected across Australia to give a total of more than 11 000 km, providing valuable new constraints on crustal structure. A further set of hitherto unexploited results comes from 150 receiver functions distributed across the continent, mostly from portable receiver sites. These new data sets provide a dramatic increase in data coverage compared with previous studies, and reveal the complex structure of the Australian continent in considerable detail. A new comprehensive model for Moho depth across Australia and its immediate environment is developed by utilizing multiple sources of information. On-shore and off-shore refraction experiments are supplemented by receiver functions from a large number of portable stations and the recently augmented set of permanent stations, and Moho picks from the full suite of reflection transects. The composite data set provides a much denser sampler of most of the continent than before, though coverage remains low in the remote areas of the Simpson and Great Sandy deserts. The various data sets provide multiple estimates of the depth to Moho in many regions and the consistency between the different techniques is high. In a number of instances, differences in estimates of Moho depth can be associated with the aspects of the structure highlighted by the particular methods. The new results allow considerable refinement of the patterns of Moho depth across the continent. Some of the thinnest crust lies beneath the Archean cratons in the Pilbara and the southern part of the Yilgarn. Thick crust is encountered beneath parts of the Proterozoic in Central Australia, and beneath the Palaeozoic Lachlan fold belt in southeastern Australia. The refined data indicate a number of zones of sharp contrast in depth to Moho, notably in the southern part of Central Australia.

  17. Relations between heat flow, topography and Moho depth for Europe

    NASA Astrophysics Data System (ADS)

    Polkowski, Marcin; Majorowicz, Jacek; Grad, Marek

    2013-04-01

    The relation between heat flow, topography and Moho depth for recent maps of Europe is presented. New heat flow map of Europe (Majorowicz and Wybraniec, 2010) is based on updated database of uncorrected heat flow values to which paleoclimatic correction is applied across the continental Europe. Correction is depth dependent due to a diffusive thermal transfer of the surface temperature forcing of which glacial-interglacial history has the largest impact. This explains some very low uncorrected heat flow values 20-30 mW/m2 in the shields, shallow basin areas of the cratons, and in other areas including orogenic belts were heat flow was likely underestimated. New integrated map of the European Moho depth (Grad et al., 2009) is the first high resolution digital map for European plate understand as an area from Ural Mountains in the east to mid-Atlantic ridge in the west, and Mediterranean Sea in the south to Spitsbergen and Barents Sea in Arctic in the north. For correlation we used: onshore heat flow density data with palaeoclimatic correction (5318 locations), topography map (30 x 30 arc seconds; Danielson and Gesch, 2011) and Moho map (longitude, latitude and Moho depth, each 0.1 degree). Analysis was done in areas where data from all three datasets were available. Continental Europe area could be divided into two large domains related with Precambrian East European craton and Palaeozoic Platform. Next two smaller areas correspond to Scandinavian Caledonides and Anatolia. Presented results show different correlations between Moho depth, elevation and heat flow for all discussed regions. For each region more detailed analysis of these relation in different elevation ranges is presented. In general it is observed that Moho depth is more significant to HF then elevation. Depending on region and elevation range HF value in mW/m2 is up to two times larger than Moho depth in km, while HF relation to elevation varies much more.

  18. Airborne Surveys of Snow Depth over Arctic Sea Ice

    NASA Technical Reports Server (NTRS)

    Kwok, R.; Panzer, B.; Leuschen, C.; Pang, S.; Markus, T.; Holt, B.; Gogineni, S.

    2011-01-01

    During the spring of 2009, an ultrawideband microwave radar was deployed as part of Operation IceBridge to provide the first cross-basin surveys of snow thickness over Arctic sea ice. In this paper, we analyze data from three approx 2000 km transects to examine detection issues, the limitations of the current instrument, and the regional variability of the retrieved snow depth. Snow depth is the vertical distance between the air \\snow and snow-ice interfaces detected in the radar echograms. Under ideal conditions, the per echogram uncertainty in snow depth retrieval is approx 4 - 5 cm. The finite range resolution of the radar (approx 5 cm) and the relative amplitude of backscatter from the two interfaces limit the direct retrieval of snow depths much below approx 8 cm. Well-defined interfaces are observed over only relatively smooth surfaces within the radar footprint of approx 6.5 m. Sampling is thus restricted to undeformed, level ice. In early April, mean snow depths are 28.5 +/- 16.6 cm and 41.0 +/- 22.2 cm over first-year and multiyear sea ice (MYI), respectively. Regionally, snow thickness is thinner and quite uniform over the large expanse of seasonal ice in the Beaufort Sea, and gets progressively thicker toward the MYI cover north of Ellesmere Island, Greenland, and the Fram Strait. Snow depth over MYI is comparable to that reported in the climatology by Warren et al. Ongoing improvements to the radar system and the utility of these snow depth measurements are discussed.

  19. Evaluation of the 7-km GEOS-5 Nature Run

    NASA Technical Reports Server (NTRS)

    Gelaro, Ronald; Putman, William M.; Pawson, Steven; Draper, Clara; Molod, Andrea; Norris, Peter M.; Ott, Lesley; Prive, Nikki; Reale, Oreste; Achuthavarier, Deepthi; Bosilovich, Michael; Buchard, Virginie; Chao, Winston; Coy, Lawrence; Cullather, Richard; da Silva, Arlindo; Darmenov, Anton; Koster, Randal; McCarty, Will; Schubert, Siegfried

    2015-01-01

    This report documents an evaluation by the Global Modeling and Assimilation Office (GMAO) of a two-year 7-km-resolution non-hydrostatic global mesoscale simulation produced with the Goddard Earth Observing System (GEOS-5) atmospheric general circulation model. The simulation was produced as a Nature Run for conducting observing system simulation experiments (OSSEs). Generation of the GEOS-5 Nature Run (G5NR) was motivated in part by the desire of the OSSE community for an improved high-resolution sequel to an existing Nature Run produced by the European Centre for Medium-Range Weather Forecasts (ECMWF), which has served the community for several years. The intended use of the G5NR in this context is for generating simulated observations to test proposed observing system designs regarding new instruments and their deployments. Because NASA's interest in OSSEs extends beyond traditional weather forecasting applications, the G5NR includes, in addition to standard meteorological components, a suite of aerosol types and several trace gas concentrations, with emissions downscaled to 10 km using ancillary information such as power plant location, population density and night-light information. The evaluation exercise described here involved more than twenty-five GMAO scientists investigating various aspects of the G5NR performance, including time mean temperature and wind fields, energy spectra, precipitation and the hydrological cycle, the representation of waves, tropical cyclones and midlatitude storms, land and ocean surface characteristics, the representation and forcing effects of clouds and radiation, dynamics of the stratosphere and mesosphere, and the representation of aerosols and trace gases. Comparisons are made with observational data sets when possible, as well as with reanalyses and other long model simulations. The evaluation is broad in scope, as it is meant to assess the overall realism of basic aspects of the G5NR deemed relevant to the conduct of OSSEs

  20. Neuromuscular characteristics and fatigue during 10 km running.

    PubMed

    Paavolainen, L; Nummela, A; Rusko, H; Häkkinen, K

    1999-11-01

    This study investigated neuromuscular characteristics and fatigue during 10 km running (10 K) performance in well-trained endurance athletes with different distance running capability. Nine high (HC) and ten low (LC) caliber endurance athletes performed the 10 K on a 200 m indoor track, constant velocity lap (CVL, 4.5 m x s(-1)) 5 times during the course of the 10 K and maximal 20 m speed test before (20 m(b)) and after (20 m(a)) the 10 K. Running velocity (V), ground contact times (CT), ground reaction forces (F) and electromyographic activity (EMG) of the leg muscles (vastus lateralis; VL, biceps femoris; BF, gastrocnemius; GA) were measured during 20 m(b), 20 m(a), and CVLs. The 10 K times differed (p<0.001) between HC and LC (36.3+/-1.2 and 39.2+/-2.0 min, respectively) but no differences were observed in 20 m(b) velocity. The 10 K led to significant (p<0.05) decreases in V, F and integrated EMG (IEMG) and increases in CTs of 20 m(a) in both groups. No changes were observed in HC or LC in F and IEMG during the CVLs but HC showed shorter (p<0.05) mean CT of CVLs than LC. A significant correlation (r = -0.56, p<0.05) was observed between the mean CT of CVLs and velocity of 10 K (V10K). Pre-activity of GA in relation to the IEMG of the total contact phase during the CVLs was higher (p<0.05) in HC than LC. The relative IEMGs of VL and GA in the propulsion phase compared to the IEMG of the 20 m(b) were lower (p<0.05) in HC than LC. In conclusion, marked fatigue took place in both HC and LC during the 10 K but the fatigue-induced changes in maximal 20 m run did not differentiate endurance athletes with different V10K. However, a capability to produce force rapidly throughout the 10 K accompanied with optimal preactivation and contact phase activation seem to be important for 10 km running performance in well trained endurance athletes.

  1. Topography of the 410 and 660 km discontinuities beneath the Korean Peninsula and southwestern Japan using teleseismic receiver functions

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Hyun; Rhie, Junkee; Park, Yongcheol; Kim, Kwang-Hee

    2014-09-01

    Topography of the 410 and 660 km seismic upper mantle discontinuities beneath the Korean Peninsula and southwestern Japan were determined using teleseismic receiver functions. P receiver functions were migrated from delayed times to corresponding piercing (conversion) points of P-to-S converted phases, using one-dimensional (1-D) and three-dimensional (3-D) models. Receiver functions were then stacked using Common Conversion Point (CCP) techniques, to enhance signal-to-noise ratios and thereby reduce uncertainty (noise). The 410 and 660 km discontinuities were clearly imaged, as positively valued amplitude peaks of CCP stacked receiver functions in the study area. Topographic variations were roughly consistent with the low temperature of the subducting Pacific Plate. However, the complex structure of the subducting Pacific Plate produced distinct changes of upper mantle discontinuities, which cannot be explained by temperature variations alone. Depression of the 410 km discontinuity, observed in a wide region extending from the Korean Peninsula to Kyushu Island, may be related to trench rollback history. Furthermore, the topography of the 660 km discontinuity varies significantly with latitude. At latitudes higher than 38°N, its depth remains unchanged, despite the presence of the stagnant slab, while significant depression has been observed at latitudes below 36°N. This may have been caused by differences in the angles of subduction of the Japan slab and the Izu-Bonin slab. However, heterogeneity of the water content of slabs may also have contributed to this topographical difference.

  2. Depth and Differentiation of the Orientale Melt Lake

    NASA Technical Reports Server (NTRS)

    Vaughan, W. M.; Head, J. W.; Hess, P. C.; Wilson, L.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    Impact melt emplacement and evolution in lunar multi-ring basins is poorly understood since impact melt deposits in basins are generally buried by mare basalt fill and obscured by subsequent impact cratering. The relatively young Orientale basin, which is only partially flooded with mare basalt, opens a rare window into basin-scale impact melts. We describe the geology of impact melt-related facies in Orientale and suggest that the central depression of Orientale may represent a solidified impact melt lake that vertically subsided shortly after basin formation due to solidification and cooling. We use Lunar Orbiter Laser Altimeter (LOLA) data to measure the depth (approx. 1.75 km) and diameter (approx 350 km) of this central depression. If all the observed subsidence of the central depression is due to solidification and cooling, the melt lake should be approx 12.5-16 km deep, far more voluminous (approx 106 km3) than the largest known differentiated igneous intrusions on Earth. We investigate the possibility that the Orientale melt lake has differentiated and model 1) the bulk composition of the melt lake, 2) the operation of melt mixing in the melt lake, and 3) the chemical evolution of the resulting liquids on the An-Fo-Qz ternary in order to predict the lithologies that might be present in the solidified Orientale melt lake. Finally, we consider the possible significance of these lithologies.

  3. Mapping the structure and depth to magnetic basement in the United States using the magnetic tilt-depth method

    NASA Astrophysics Data System (ADS)

    Salem, A.; Williams, S.; Fairhead, J.; Ravat, D.; Blakely, R.

    2008-05-01

    We provide a rationale for rapidly assessing the depth and structure of sedimentary basins from magnetic anomaly data. Our methodology is based on "tilt-depth" calculated strictly from first-order derivatives of the total magnetic field. We assume a simple buried vertical contact model such that the 0 degree contour of the tilt derivative closely follows the edge of the vertical contact, while the distance between the 0 and +/-45 degree contours provides an estimate of the depth to the top of the buried contact. We have applied the tilt-depth method to two magnetic databases with very different scales. In the first application, we used the Magnetic Anomaly Map of North America covering the continental United States, gridded at a sample interval of 1 km. Calculated depths show a strong correlation with known areas of shallow basement and sedimentary basins. To quantitatively evaluate the results, we low-pass filtered the calculated depths, desampled the grid to a 1-degree sample interval, and compared with a grid of sediment thickness based on drilling data (Laske and Masters, 1997). In visual comparisons, these two datasets show a striking correlation between basement highs and lows, and, quantitatively, the overall correlation coefficient between the two grids is 0.87. We also applied the tilt-depth methodology to high-resolution aeromagnetic data from the Olympic Peninsula of Washington State. To first order, the Olympic Peninsula is a massive east-plunging anticline consisting of two distinct subduction-related terranes: An essentially nonmagnetic core of highly deformed Tertiary sedimentary rocks, and a periphery of highly magnetic, early Eocene volcanic rocks. The tilt-depth method successfully identified a number of important tectonic elements known from geologic mapping. The steeply dipping thrust contact between core and periphery rocks was clearly delineated, and other more subtle magnetic anomalies within the periphery volcanic rocks and even within the

  4. Constraining depth range of S wave velocity decrease after large earthquakes near Parkfield, California

    NASA Astrophysics Data System (ADS)

    Wu, Chunquan; Delorey, Andrew; Brenguier, Florent; Hadziioannou, Celine; Daub, Eric G.; Johnson, Paul

    2016-06-01

    We use noise correlation and surface wave inversion to measure the S wave velocity changes at different depths near Parkfield, California, after the 2003 San Simeon and 2004 Parkfield earthquakes. We process continuous seismic recordings from 13 stations to obtain the noise cross-correlation functions and measure the Rayleigh wave phase velocity changes over six frequency bands. We then invert the Rayleigh wave phase velocity changes using a series of sensitivity kernels to obtain the S wave velocity changes at different depths. Our results indicate that the S wave velocity decreases caused by the San Simeon earthquake are relatively small (~0.02%) and access depths of at least 2.3 km. The S wave velocity decreases caused by the Parkfield earthquake are larger (~0.2%), and access depths of at least 1.2 km. Our observations can be best explained by material damage and healing resulting mainly from the dynamic stress perturbations of the two large earthquakes.

  5. Intermediate-depth earthquake faulting by dehydration embrittlement with negative volume change

    NASA Astrophysics Data System (ADS)

    Jung, Haemyeong; Green, Harry W., II; Dobrzhinetskaya, Larissa F.

    2004-04-01

    Earthquakes are observed to occur in subduction zones to depths of approximately 680km, even though unassisted brittle failure is inhibited at depths greater than about 50km, owing to the high pressures and temperatures. It is thought that such earthquakes (particularly those at intermediate depths of 50-300km) may instead be triggered by embrittlement accompanying dehydration of hydrous minerals, principally serpentine. A problem with failure by serpentine dehydration is that the volume change accompanying dehydration becomes negative at pressures of 2-4GPa (60-120km depth), above which brittle fracture mechanics predicts that the instability should be quenched. Here we show that dehydration of antigorite serpentinite under stress results in faults delineated by ultrafine-grained solid reaction products formed during dehydration. This phenomenon was observed under all conditions tested (pressures of 1-6GPa temperatures of 650-820°C), independent of the sign of the volume change of reaction. Although this result contradicts expectations from fracture mechanics, it can be explained by separation of fluid from solid residue before and during faulting, a hypothesis supported by our observations. These observations confirm that dehydration embrittlement is a viable mechanism for nucleating earthquakes independent of depth, as long as there are hydrous minerals breaking down under a differential stress.

  6. Depth dependence of earthquake frequency-magnitude distributions in California: Implications for rupture initiation

    USGS Publications Warehouse

    Mori, J.; Abercrombie, R.E.

    1997-01-01

    Statistics of earthquakes in California show linear frequency-magnitude relationships in the range of M2.0 to M5.5 for various data sets. Assuming Gutenberg-Richter distributions, there is a systematic decrease in b value with increasing depth of earthquakes. We find consistent results for various data sets from northern and southern California that both include and exclude the larger aftershock sequences. We suggest that at shallow depth (???0 to 6 km) conditions with more heterogeneous material properties and lower lithospheric stress prevail. Rupture initiations are more likely to stop before growing into large earthquakes, producing relatively more smaller earthquakes and consequently higher b values. These ideas help to explain the depth-dependent observations of foreshocks in the western United States. The higher occurrence rate of foreshocks preceding shallow earthquakes can be interpreted in terms of rupture initiations that are stopped before growing into the mainshock. At greater depth (9-15 km), any rupture initiation is more likely to continue growing into a larger event, so there are fewer foreshocks. If one assumes that frequency-magnitude statistics can be used to estimate probabilities of a small rupture initiation growing into a larger earthquake, then a small (M2) rupture initiation at 9 to 12 km depth is 18 times more likely to grow into a M5.5 or larger event, compared to the same small rupture initiation at 0 to 3 km. Copyright 1997 by the American Geophysical Union.

  7. The Mechanism of Intermediate-Depth Earthquakes in the Hindu Kush

    NASA Astrophysics Data System (ADS)

    Chen, W.; Warren, L. M.

    2011-12-01

    The Hindu Kush mountains, located near the borders of Afghanistan, Tajikistan, Pakistan, and China, formed from the collision of India with Eurasia beginning in the Eocene (~55 Ma). The collision resulted in the subduction of the Indian plate. The subduction history has been inferred from seismic tomography, earthquake locations, and thermal modeling. Some of these studies have suggested that the Indian plate subducted northward, started to overturn, and then gradually broke off towards the east. Earthquakes in this region occur down to ~250 km depth, but why they occur is unknown. They may be related to slab break-off or dehydration in the oceanic crust. To distinguish between these mechanisms, we investigate the rupture processes of 22 intermediate-depth earthquakes with Mw between 5.5 and 7.4 that occurred from 1991 to 2005. The ruptures tend to propagate subhorizontally. The earthquakes are located in 3 main clusters. Cluster I is located <150 km depth and has variable focal mechanism orientations. In Cluster II, which is located between 185 and 225 km depth, the focal mechanisms change their orientation gradually with the shape of the slab. Cluster III, located between 210 and 240 km depth to the east of Cluster II, is the most consistent one: most of the focal mechanisms are similar to one another and the rupture vectors tend to point outwards from the slab.

  8. Intermediate-depth earthquake faulting by dehydration embrittlement with negative volume change.

    PubMed

    Jung, Haemyeong; Green II, Harry W; Dobrzhinetskaya, Larissa F

    2004-04-01

    Earthquakes are observed to occur in subduction zones to depths of approximately 680 km, even though unassisted brittle failure is inhibited at depths greater than about 50 km, owing to the high pressures and temperatures. It is thought that such earthquakes (particularly those at intermediate depths of 50-300 km) may instead be triggered by embrittlement accompanying dehydration of hydrous minerals, principally serpentine. A problem with failure by serpentine dehydration is that the volume change accompanying dehydration becomes negative at pressures of 2-4 GPa (60-120 km depth), above which brittle fracture mechanics predicts that the instability should be quenched. Here we show that dehydration of antigorite serpentinite under stress results in faults delineated by ultrafine-grained solid reaction products formed during dehydration. This phenomenon was observed under all conditions tested (pressures of 1-6 GPa; temperatures of 650-820 degrees C), independent of the sign of the volume change of reaction. Although this result contradicts expectations from fracture mechanics, it can be explained by separation of fluid from solid residue before and during faulting, a hypothesis supported by our observations. These observations confirm that dehydration embrittlement is a viable mechanism for nucleating earthquakes independent of depth, as long as there are hydrous minerals breaking down under a differential stress.

  9. Synthesis and evaluation of new antitumor 3-aminomethyl-4,11-dihydroxynaphtho[2,3-f]indole-5,10-diones.

    PubMed

    Shchekotikhin, Andrey E; Glazunova, Valeria A; Dezhenkova, Lyubov G; Luzikov, Yuri N; Buyanov, Vladimir N; Treshalina, Helena M; Lesnaya, Nina A; Romanenko, Vladimir I; Kaluzhny, Dmitry N; Balzarini, Jan; Agama, Keli; Pommier, Yves; Shtil, Alexander A; Preobrazhenskaya, Maria N

    2014-10-30

    A series of new 3-aminomethyl-4,11-dihydroxynaphtho[2,3-f]indole-5,10-diones 6-13 bearing the cyclic diamine in the position 3 of the indole ring was synthesized. The majority of new compounds demonstrated a superior cytotoxicity than doxorubicin against a panel of mammalian tumor cells with determinants of altered drug response, that is, Pgp expression or p53 inactivation. For naphtho[2,3-f]indole-5,10-diones 6-9 bearing 3-aminopyrrolidine in the side chains, the ability to bind double-stranded DNA and inhibit topoisomerases 1 and 2 mediated relaxation of supercoiled DNA were demonstrated. Only one isomer, (R)-4,11-dihydroxy-3-((pyrrolidin-3-ylamino)methyl)-1H-naphtho[2,3-f]indole-5,10-dione (7) induced the formation of specific DNA cleavage products similar to the known topoisomerase 1 inhibitors camptothecin and indenoisoquinoline MJ-III-65, suggesting a role of the structure of the side chain of 3-aminomethylnaphtho[2,3-f]indole-5,10-diones in interaction with the target. Compound 7 demonstrated an antitumor activity in mice with P388 leukemia transplants whereas its enantiomer 6 was inactive. Thus, 3-aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione emerge as a new prospective chemotype for the search of antitumor agents.

  10. 3-Aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione for circumvention of anticancer drug resistance.

    PubMed

    Shchekotikhin, Andrey E; Shtil, Alexander A; Luzikov, Yuri N; Bobrysheva, Tatyana V; Buyanov, Vladimir N; Preobrazhenskaya, Maria N

    2005-03-15

    A series of 3-aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione was synthesized by Mannich reaction or by the transamination of 3-dimethylaminomethyl 4,11-dihydroxy- or 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione. The potency of novel derivatives was tested on a National Cancer Institute panel of 60 human tumor cell lines as well as in cells with genetically defined determinants of cytotoxic drug resistance, P-glycoprotein (Pgp) expression, and p53 inactivation. Mannich derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione with an additional amino function in their side chain, demonstrated equal cytotoxicity against the parental K562 leukemia cells and their Pgp-positive subline, whereas the latter showed approximately 7-fold resistance to adriamycin, a Pgp transported drug. 3-(1-Piperazinyl)methyl and 3-(quinuclidin-3-yl)aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione killed HCT116 colon carcinoma cells (carrying wild type p53) and their p53-null variant within the similar range of concentrations. We conclude that Mannich modification of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione, especially when cyclic diamine (e.g., piperazine, quinuclidine) is used, confers an important feature to the resulting compounds, namely, the potency for tumor cells otherwise resistant to a variety of anticancer drugs.

  11. KM3NeT Digital Optical Module electronics

    NASA Astrophysics Data System (ADS)

    Real, Diego

    2016-04-01

    The KM3NeT collaboration is currently building of a neutrino telescope with a volume of several cubic kilometres at the bottom of the Mediterranean Sea. The telescope consists of a matrix of Digital Optical Modules that will detect the Cherenkov light originated by the interaction of the neutrinos in the proximity of the detector. This contribution describes the main components of the read-out electronics of the Digital Optical Module: the Power Board, which delivers all the power supply required by the Digital Optical Molule electronics; the Central Logic Board, the main core of the read-out system, hosting 31 Time to Digital Converters with 1 ns resolution and the White Rabbit protocol embedded in the Central Logic Board Field Programmable Gate Array; the Octopus boards, that transfer the Low Voltage Digital Signals from the PMT bases to the Central Logic Board and finally the PMT bases, in charge of converting the analogue signal produced in the 31 3" PMTs into a Low Voltage Digital Signal.

  12. Stratospheric microbiology at 20 km over the Pacific Ocean

    USGS Publications Warehouse

    Smith, David J.; Griffin, Dale W.; Schuerger, Andrew C.

    2010-01-01

    An aerobiology sampling flight at 20 km was conducted on 28 April 2008 over the Pacific Ocean (36.5° N, 118–149° W), a period of time that coincided with the movement of Asian dust across the ocean. The aim of this study was to confirm the presence of viable bacteria and fungi within a transoceanic, atmospheric bridge and to improve the resolution of flight hardware processing techniques. Isolates of the microbial strains recovered were analyzed with ribosomal ribonucleic acid (rRNA) sequencing to identify bacterial species Bacillus sp., Bacillus subtilis, Bacillus endophyticus, and the fungal genus Penicillium. Satellite imagery and ground-based radiosonde observations were used to measure dust movement and characterize the high-altitude environment at the time of collection. Considering the atmospheric residency time (7–10 days), the extreme temperature regime of the environment (-75°C), and the absence of a mechanism that could sustain particulates at high altitude, it is unlikely that our samples indicate a permanent, stratospheric ecosystem. However, the presence of viable fungi and bacteria in transoceanic stratosphere remains relevant to understanding the distribution and extent of microbial life on Earth.

  13. A 233 km tunnel for lepton and hadron colliders

    SciTech Connect

    Summers, D. J.; Cremaldi, L. M.; Datta, A.; Duraisamy, M.; Luo, T.; Lyons, G. T.

    2012-12-21

    A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of e{sup +}e{sup -}, pp-bar , and {mu}{sup +}{mu}{sup -} collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV e{sup +}e{sup -} colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV e{sup +}e{sup -} collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV pp-bar collider uses the high intensity Fermilab p-bar source, exploits high cross sections for pp-bar production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.

  14. Nausea is associated with endotoxemia during a 161-km ultramarathon.

    PubMed

    Stuempfle, Kristin J; Valentino, Taylor; Hew-Butler, Tamara; Hecht, Frederick M; Hoffman, Martin D

    2016-09-01

    This study explored possible contributing factors to gastrointestinal distress, including endotoxemia, hyperthermia, dehydration and nutrition, during a 161-km ultramarathon. Thirty runners participated in the study and 20 finished the race. At three checkpoints and the finish, runners were interviewed to assess the incidence and severity of 12 gastrointestinal symptoms and to determine dietary intake. Core temperature was measured at the same locations. Runners were weighed pre-race, at the three checkpoints and the finish to monitor hydration status. Blood markers for endotoxemia (sCD14) and inflammation (interleukin-6 and C-reactive protein) were measured pre- and post-race. Gastrointestinal symptoms were experienced by most runners (80%), with nausea being the most common complaint (60%). Runners with nausea experienced significantly greater (P = 0.02) endotoxemia than those without nausea (sCD14 mean increase 0.7 versus 0.5 µg · mL(-1)). There was a significant positive correlation (r = 0.652, P = 0.005) between nausea severity and endotoxemia level. Inflammatory response, core temperature, hydration level and race diet were similar between runners with and without nausea. This study links endotoxemia to nausea in ultramarathon runners. Other possible contributing factors to nausea such as hyperthermia, dehydration and nutrition did not appear to play a role in the symptomatic runners in this study. PMID:26707127

  15. ASIC design in the KM3NeT detector

    NASA Astrophysics Data System (ADS)

    Gajanana, D.; Gromov, V.; Timmer, P.

    2013-02-01

    In the KM3NeT project [1], Cherenkov light from the muon interactions with transparent matter around the detector, is used to detect neutrinos. Photo multiplier tubes (PMT) used as photon sensor, are housed in a glass sphere (aka Optical Module) to detect single photons from the Cherenkov light. The PMT needs high operational voltage ( ~ 1.5 kV) and is generated by a Cockroft-Walton (CW) multiplier circuit. The electronics required to control the PMT's and collect the signals is integrated in two ASIC's namely: 1) a front-end mixed signal ASIC (PROMiS) for the readout of the PMT and 2) an analog ASIC (CoCo) to generate pulses for charging the CW circuit and to control the feedback of the CW circuit. In this article, we discuss the two integrated circuits and test results of the complete setup. PROMiS amplifies the input charge, converts it to a pulse width and delivers the information via LVDS signals. These LVDS signals carry accurate information on the Time of arrival ( < 2 ns) and Time over Threshold. A PROM block provides unique identification to the chip. The chip communicates with the control electronics via an I2C bus. This unique combination of the ASIC's results in a very cost and power efficient PMT base design.

  16. Focus cues affect perceived depth

    PubMed Central

    Watt, Simon J.; Akeley, Kurt; Ernst, Marc O.; Banks, Martin S.

    2007-01-01

    Depth information from focus cues—accommodation and the gradient of retinal blur—is typically incorrect in three-dimensional (3-D) displays because the light comes from a planar display surface. If the visual system incorporates information from focus cues into its calculation of 3-D scene parameters, this could cause distortions in perceived depth even when the 2-D retinal images are geometrically correct. In Experiment 1 we measured the direct contribution of focus cues to perceived slant by varying independently the physical slant of the display surface and the slant of a simulated surface specified by binocular disparity (binocular viewing) or perspective/texture (monocular viewing). In the binocular condition, slant estimates were unaffected by display slant. In the monocular condition, display slant had a systematic effect on slant estimates. Estimates were consistent with a weighted average of slant from focus cues and slant from disparity/texture, where the cue weights are determined by the reliability of each cue. In Experiment 2, we examined whether focus cues also have an indirect effect on perceived slant via the distance estimate used in disparity scaling. We varied independently the simulated distance and the focal distance to a disparity-defined 3-D stimulus. Perceived slant was systematically affected by changes in focal distance. Accordingly, depth constancy (with respect to simulated distance) was significantly reduced when focal distance was held constant compared to when it varied appropriately with the simulated distance to the stimulus. The results of both experiments show that focus cues can contribute to estimates of 3-D scene parameters. Inappropriate focus cues in typical 3-D displays may therefore contribute to distortions in perceived space. PMID:16441189

  17. Lunar Far Side Regolith Depth

    NASA Astrophysics Data System (ADS)

    Bart, G. D.; Melosh, H. J.

    2005-08-01

    The lunar far side contains the South Pole Aitken Basin, which is the largest known impact basin in the solar system, and is enhanced in titanium and iron compared to the rest of the lunar highlands. Although we have known of this enigmatic basin since the 60's, most lunar photography and science covered the equatorial near side where the Apollo spacecraft landed. With NASA's renewed interest in the Moon, the South Pole Aitken Basin is a likely target for future exploration. The regolith depth is a crucial measurement for understanding the source of the surface material in the Basin. On the southern far side of the Moon (20 S, 180 W), near the north edge of the Basin, we determined the regolith depth by examining 11 flat-floored craters about 200 m in diameter. We measured the ratio of the diameter of the flat floor to the diameter of the crater, and used it to calculate the regolith thickness using the method of Quaide and Oberbeck (1968). We used Apollo 15 panoramic images --- still the highest resolution images available for this region of the Moon. We found the regolith depth at that location to be about 40 m. This value is significantly greater than values for the lunar near side: 3 m (Oceanus Procellarum), 16 m (Hipparchus), and 1-10 m at the Surveyor landing sites. The thicker value obtained for the far side regolith is consistent with the older age of the far side. It also suggests that samples returned from the far side may have originated from deeper beneath the surface than their near side counterparts.

  18. Depth-Duration Frequency of Precipitation for Oklahoma

    USGS Publications Warehouse

    Tortorelli, Robert L.; Rea, Alan; Asquith, William H.

    1999-01-01

    A regional frequency analysis was conducted to estimate the depth-duration frequency of precipitation for 12 durations in Oklahoma (15, 30, and 60 minutes; 1, 2, 3, 6, 12, and 24 hours; and 1, 3, and 7 days). Seven selected frequencies, expressed as recurrence intervals, were investigated (2, 5, 10, 25, 50, 100, and 500 years). L-moment statistics were used to summarize depth-duration data and to determine the appropriate statistical distributions. Three different rain-gage networks provided the data (15minute, 1-hour, and 1-day). The 60-minute, and 1-hour; and the 24-hour, and 1-day durations were analyzed separately. Data were used from rain-gage stations with at least 10-years of record and within Oklahoma or about 50 kilometers into bordering states. Precipitation annual maxima (depths) were determined from the data for 110 15-minute, 141 hourly, and 413 daily stations. The L-moment statistics for depths for all durations were calculated for each station using unbiased L-mo-ment estimators for the mean, L-scale, L-coefficient of variation, L-skew, and L-kur-tosis. The relation between L-skew and L-kurtosis (L-moment ratio diagram) and goodness-of-fit measures were used to select the frequency distributions. The three-parameter generalized logistic distribution was selected to model the frequencies of 15-, 30-, and 60-minute annual maxima; and the three-parameter generalized extreme-value distribution was selected to model the frequencies of 1-hour to 7-day annual maxima. The mean for each station and duration was corrected for the bias associated with fixed interval recording of precipitation amounts. The L-scale and spatially averaged L-skew statistics were used to compute the location, scale, and shape parameters of the selected distribution for each station and duration. The three parameters were used to calculate the depth-duration-frequency relations for each station. The precipitation depths for selected frequencies were contoured from weighted depth

  19. The global Moho depth map for continental crust

    NASA Astrophysics Data System (ADS)

    Baranov, Alexey; Morelli, Andrea

    2014-05-01

    Different tectonic units cover the continents: platform, orogens and depression structures. This structural variability is reflected both in thickness and physical properties of the crust. We present a new global Moho map for the continental crust, derived from geophysical data selected from the literature and regional crustal models. The Moho depth is represented with a resolution of 1x1 on a Cartesian grid. A large volume of new data has been analyzed: mostly active seismic experiments, as well as receiver functions and geological studies. We have used the following regional studies: for Europe and Greenland, models EPcrust [Molinari and Morelli, 2011]and EUNAseis [Artemieva and Thybo, 2103]; for North Asia, Moho models from [Cherepanova et al., 2013; Iwasaki et al., 2013; Pavlenkova, 1996]; for Central and Southern Asia, model AsCrust [Baranov, 2010] with updates for India [Reddy and Rao, 2013]; China [Teng et al., 2013];Arabian [Mechie et al., 2013]; for Africa, the model by [Pasyanos and Nyblade, 2007] as a framework and added many others regional studies; for South America, models by [Assumpção et al.,2013; Chulick et al.,2013; Lloyd et al., 2010]; for North America, the model by [Keller, 2013]; for Australia, the model by [Salmon et al., 2013]; for Antarctica, model ANTMoho [Baranov and Morelli, 2013] with update for West Antarctica (POLENET project, [Chaput et al., 2013]). For two orogens we have found the maximum depth at - 75 km (Tibet and Andes). In our model the average thickness of the continental crust is about 34 km (st. deviation 9 km) whereas in CRUST 2.0 model the average Moho for continental areas is about 38 km. The new Moho model for continents exhibits some remarkable disagreement at places with respect to global model CRUST 2.0. The difference in crustal thickness between these two models may amount up to 30 km, mainly due to improved resolution of our model's Moho boundary. There are significant changes in several regions: among them

  20. Static stereo vision depth distortions in teleoperation

    NASA Technical Reports Server (NTRS)

    Diner, D. B.; Von Sydow, M.

    1988-01-01

    A major problem in high-precision teleoperation is the high-resolution presentation of depth information. Stereo television has so far proved to be only a partial solution, due to an inherent trade-off among depth resolution, depth distortion and the alignment of the stereo image pair. Converged cameras can guarantee image alignment but suffer significant depth distortion when configured for high depth resolution. Moving the stereo camera rig to scan the work space further distorts depth. The 'dynamic' (camera-motion induced) depth distortion problem was solved by Diner and Von Sydow (1987), who have quantified the 'static' (camera-configuration induced) depth distortion. In this paper, a stereo image presentation technique which yields aligned images, high depth resolution and low depth distortion is demonstrated, thus solving the trade-off problem.

  1. Measurement of the atmospheric muon flux at 3500 m depth with the NEMO Phase-2 detector

    NASA Astrophysics Data System (ADS)

    Distefano, C.; Aiello, S.; Ameli, F.; Anghinolfi, M.; Barbarino, G.; Barbarito, E.; Barbato, F.; Beverini, N.; Biagi, S.; Bouhadef, B.; Bozza, C.; Cacopardo, G.; Calamai, M.; Calì, C.; Capone, A.; Caruso, F.; Ceres, A.; Chiarusi, T.; Circella, M.; Cocimano, R.; Coniglione, R.; Costa, M.; Cuttone, G.; D'Amato, C.; D'Amico, A.; De Bonis, G.; De Luca, V.; Deniskina, N.; De Rosa, G.; Di Capua, F.; Fermani, P.; Flaminio, V.; Fusco, L. A.; Garufi, F.; Giordano, V.; Gmerk, A.; Grasso, R.; Grella, G.; Hugon, C.; Imbesi, M.; Kulikovskiy, V.; Larosa, G.; Lattuada, D.; Leismueller, K. P.; Leonora, E.; Litrico, P.; Lonardo, A.; Longhitano, F.; Lo Presti, D.; Maccioni, E.; Margiotta, A.; Martini, A.; Masullo, R.; Migliozzi, P.; Migneco, E.; Miraglia, A.; Mollo, C. M.; Mongelli, M.; Morganti, M.; Musico, P.; Musumeci, M.; Nicolau, C. A.; Orlando, A.; Papaleo, R.; Pellegrino, C.; Pellegriti, M. G.; Perrina, C.; Piattelli, P.; Pugliatti, C.; Pulvirenti, S.; Orselli, A.; Raffaelli, F.; Randazzo, N.; Riccobene, G.; Rovelli, A.; Sanguineti, M.; Sapienza, P.; Sciacca, V.; Sgura, I.; Simeone, F.; Sipala, V.; Speziale, F.; Spina, M.; Spitaleri, A.; Spurio, M.; Stellacci, S. M.; Taiuti, M.; Terreni, G.; Trasatti, L.; Trovato, A.; Ventura, C.; Vicini, P.; Viola, S.; Vivolo, D.

    2016-07-01

    In March 2013, the Nemo Phase-2 tower was successfully deployed at 80 km off-shore Capo Passero (Italy) at 3500 m depth. The tower operated continuously until August 2014. We present the results of the atmospheric muon analysis from the data collected in 411 days of live time. The zenith-angle distribution of atmospheric muons was measured and results compared with Monte Carlo simulations. The associated depth intensity relation was then measured and compared with previous measurements and theoretical predictions.

  2. Lunar crater depths from orbiter IV long-focus photographs

    USGS Publications Warehouse

    Arthur, D.W.G.

    1974-01-01

    The paper presents method and results for the determination of the depths of more than 1900 small lunar craters from measures of shadows on the long-focus pictures obtained by Lunar Orbiter IV. The method for converting the measured shadow length into the true length in nature of the shadow hypotenuse is new and is applicable to other planetary bodies provided comparable spacecraft ephemerides are available. The measures were made with a simple surveyor's plotting scale on the standard Orbiter IV photographic enlargements. The results indicate that the smaller lunar (D < 30 km) craters are appreciably deeper than is indicated by earlier work using imagery obtained at terrestrial observatories. ?? 1974.

  3. File Specification for the 7-km GEOS-5 Nature Run, Ganymed Release Non-Hydrostatic 7-km Global Mesoscale Simulation

    NASA Technical Reports Server (NTRS)

    da Silva, Arlindo M.; Putman, William; Nattala, J.

    2014-01-01

    This document describes the gridded output files produced by a two-year global, non-hydrostatic mesoscale simulation for the period 2005-2006 produced with the non-hydrostatic version of GEOS-5 Atmospheric Global Climate Model (AGCM). In addition to standard meteorological parameters (wind, temperature, moisture, surface pressure), this simulation includes 15 aerosol tracers (dust, sea-salt, sulfate, black and organic carbon), O3, CO and CO2. This model simulation is driven by prescribed sea-surface temperature and sea-ice, daily volcanic and biomass burning emissions, as well as high-resolution inventories of anthropogenic sources. A description of the GEOS-5 model configuration used for this simulation can be found in Putman et al. (2014). The simulation is performed at a horizontal resolution of 7 km using a cubed-sphere horizontal grid with 72 vertical levels, extending up to to 0.01 hPa (approximately 80 km). For user convenience, all data products are generated on two logically rectangular longitude-latitude grids: a full-resolution 0.0625 deg grid that approximately matches the native cubed-sphere resolution, and another 0.5 deg reduced-resolution grid. The majority of the full-resolution data products are instantaneous with some fields being time-averaged. The reduced-resolution datasets are mostly time-averaged, with some fields being instantaneous. Hourly data intervals are used for the reduced-resolution datasets, while 30-minute intervals are used for the full-resolution products. All full-resolution output is on the model's native 72-layer hybrid sigma-pressure vertical grid, while the reduced-resolution output is given on native vertical levels and on 48 pressure surfaces extending up to 0.02 hPa. Section 4 presents additional details on horizontal and vertical grids. Information of the model surface representation can be found in Appendix B. The GEOS-5 product is organized into file collections that are described in detail in Appendix C. Additional

  4. Kinematics of the New Zealand plate boundary: Relative motion by GPS across networks of 1000 km and 50 km spacing

    NASA Technical Reports Server (NTRS)

    Meertens, Charles M.; Rocken, Christian; Perin, Barbara; Walcott, Richard

    1993-01-01

    The NASA/DOSE 'Kinematics of the New Zealand Plate Boundary' experiment is a four-year cooperative Global Positioning System (GPS) experiment involving 6 universities and institutions in New Zealand and the United States. The investigation covers two scales, the first on the scale of plates (approximately 1000 km) and the second is on the scale of the plate boundary zone (approximately 50 km). In the first portion of the experiment, phase A, the objective is to make direct measurements of tectonic plate motion between the Australian and Pacific plates using GPS in order to determine the Euler vector of this plate pair. The phase A portion of this experiment was initiated in December 1992 with the first-epoch baseline measurements on the large scale network. The network will be resurveyed two years later to obtain velocities. The stations which were observed for phase A are shown and listed. Additional regional stations which will be used for this study are listed and are part of either CIGNET or other global tracking networks. The phase A portion of the experiment is primarily the responsibility of the UNAVCO investigators. Therefore, this report concentrates on phase A. The first year of NASA funding for phase A included only support for the field work. Processing and analysis will take place with the second year of funding. The second part of the experiemnt measured relative motion between the Australian and Pacific plates across the pate boundary zone between Hokitika and Christchurch on the South Island of New Zealand. The extent and rate of deformation will be determined by comparisons with historical, conventional surveys and by repeated GPS measurements to be made in two years. This activity was the emphasis of the LDGO portion of the study. An ancillary experiment, phase C, concentrated on plate boundary deformation in the vicinity of Wellington and was done as part of training during the early portion of the field campaign. Details of the objectives of the

  5. A high resolution (1 km) groundwater model for Indonesia

    NASA Astrophysics Data System (ADS)

    Sutanudjaja, Edwin; Verkaik, Jarno; de Graaf, Inge; van Beek, Rens; Erkens, Gilles; Bierkens, Marc

    2015-04-01

    Groundwater is important in many parts of Indonesia. It serves as a primary source of drinking water and industrial activities. During times of drought, it sustains water flows in streams, rivers, lakes and wetlands, and thus support ecosystem habitat and biodiversity as well as preventing hazardous forest fire. Besides its importance, groundwater is known as a vulnerable resource as unsustainable groundwater exploitation and management occurs in many areas of the country. Therefore, in order to ensure sustainable management of groundwater resources, monitoring and predicting groundwater changes in Indonesia are imperative. However, large extent groundwater models to assess these changes on a regional scale are almost non-existent and are hampered by the strong topographical and lithological transitions that characterize Indonesia. In this study, we built an 1 km resolution groundwater model for the entire Indonesian archipelago (total inland area: about 2 million km2). We adopted the approaches of Sutanudjaja et al. (2011, 2014a) and de Graaf et al. (2014) in order to make a MODFLOW (Harbaugh et al., 2000) groundwater model by using only global datasets. Aquifer schematization and properties of the groundwater model were developed from available global lithological maps (e.g. Dürr et al., 2005; Gleeson et al., 2011; Hartmann & Moorsdorf, 2012; Gleeson et al., 2014). We forced the groundwater model with the recent output of global hydrological model PCR-GLOBWB version 2.0 (Sutanudjaja et al., 2014b; van Beek et al., 2011), specifically the long term average of groundwater recharge and average surface water levels derived from channel discharge. Simulation results were promising. The MODFLOW model converged with realistic aquifer properties (i.e. transmissivities) and produced reasonable groundwater head spatial distribution reflecting the positions of major groundwater bodies and surface water bodies in the country. In Vienna, we aim to show and demonstrate these

  6. Processing techniques for global land 1-km AVHRR data

    USGS Publications Warehouse

    Eidenshink, Jeffery C.; Steinwand, Daniel R.; Wivell, Charles E.; Hollaren, Douglas M.; Meyer, David

    1993-01-01

    The U.S. Geological Survey's (USGS) Earth Resources Observation Systems (EROS) Data Center (EDC) in cooperation with several international science organizations has developed techniques for processing daily Advanced Very High Resolution Radiometer (AVHRR) 1-km data of the entire global land surface. These techniques include orbital stitching, geometric rectification, radiometric calibration, and atmospheric correction. An orbital stitching algorithm was developed to combine consecutive observations acquired along an orbit by ground receiving stations into contiguous half-orbital segments. The geometric rectification process uses an AVHRR satellite model that contains modules for forward mapping, forward terrain correction, and inverse mapping with terrain correction. The correction is accomplished by using the hydrologic features coastlines and lakes from the Digital Chart of the World. These features are rasterized into the satellite projection and are matched to the AVHRR imagery using binary edge correlation techniques. The resulting coefficients are related to six attitude correction parameters: roll, roll rate, pitch, pitch rate, yaw, and altitude. The image can then be precision corrected to a variety of map projections and user-selected image frames. Because the AVHRR lacks onboard calibration for the optical wavelengths, a series of time-variant calibration coefficients derived from vicarious calibration methods and are used to model the degradation profile of the instruments. Reducing atmospheric effects on AVHRR data is important. A method has been develop that will remove the effects of molecular scattering and absorption from clear sky observations, using climatological measurements of ozone. Other methods to remove the effects of water vapor and aerosols are being investigated.

  7. Gastrointestinal distress is common during a 161-km ultramarathon.

    PubMed

    Stuempfle, Kristin Jean; Hoffman, Martin Dean

    2015-01-01

    This study examined the incidence, severity, and timing of gastrointestinal (GI) symptoms in finishers and non-finishers of the 161-km Western States Endurance Run. A total of 272 runners (71.0% of starters) completed a post-race questionnaire that assessed the incidence and severity (none = 0, mild = 1, moderate = 2, severe = 3, very severe = 4) of 12 upper (reflux/heartburn, belching, stomach bloating, stomach cramps/pain, nausea, vomiting) and lower (intestinal cramps/pain, flatulence, side ache/stitch, urge to defecate, loose stool/diarrhoea, intestinal bleeding/bloody faeces) GI symptoms experienced during each of four race segments. GI symptoms were experienced by most runners (96.0%). Flatulence (65.9% frequency, mean value 1.0, s = 0.6 severity), belching (61.3% frequency, mean value 1.0, s = 0.6 severity), and nausea (60.3% frequency, mean value 1.0, s = 0.7 severity) were the most common symptoms. Among race finishers, 43.9% reported that GI symptoms affected their race performance, with nausea being the most common symptom (86.0%). Among race non-finishers, 35.6% reported that GI symptoms were a reason for dropping out of the race, with nausea being the most common symptom (90.5%). For both finishers and non-finishers, nausea was greatest during the most challenging and hottest part of the race. GI symptoms are very common during ultramarathon running, and in particular, nausea is the most common complaint for finishers and non-finishers. PMID:25716739

  8. Hundred lightcurves of sub-km main-belt asteroids

    NASA Astrophysics Data System (ADS)

    Yoshida, F.; Souami, D.; Bouquillon, S.; Nakamura, T.; Dermawan, B.; Yagi, M.; Souchay, J.

    2014-07-01

    We observed a single sky field near opposition and near the ecliptic plane using the Subaru telescope equipped with the Suprime-Cam. Taking advantage of the wide field of view (FOV) for the Suprime-Cam, the plan was to obtain 100 lightcurves of asteroids at the same time. The total observing time interval was about 8 hours on September 2, 2002, with 2-min exposures. We detected 147 moving objects in the single FOV (34'×27') on the Suprime-Cam (see Figure). Of those, 112 detections corresponded to different objects. We used the R filter during almost the entire observing run, but we took a few images with the B filter at the beginning, the middle, and the end of the run. We classified main-belt asteroids into S- and C-complexes with the B-R color of the object (Yoshida & Nakamura 2007). Although we carefully avoided regions of bright stars, the sky in the images taken by Suprime-Cam were actually crowded with faint objects. Therefore, the asteroids overlapped with background stars very often. Thus, it was very difficult to get lightcurves with high accuracy. We modified the GAIA-GBOT (Ground Based Optical Tracking) PIPELINE to measure the position and brightness of each object (Bouquillon et al. 2012). Once the objects were identified and their positions measured in pixel coordinates, the pipeline proceeded to the astrometric calibration and then to the photometric calibrations with the Guide Star Catalog II (Lasker et al. 2008). The pipeline produced time series of photometry for each object. The average brightness of each lightcurve ranged between 19--24 mag. We then estimated the rotational period from the lightcurve of each object. In our presentation, we will show the spin-period distribution of sub- km main-belt asteroids and compare it with that of large main-belt asteroids obtained from the lightcurve catalogue.

  9. Estimation of Land Surface Temperature from 1-km AVHRR data

    NASA Astrophysics Data System (ADS)

    Frey, Corinne

    2016-04-01

    In order to re-process DLRs 1km AVHRR data archive to different geophysical and descriptive parameters of the land surface and the atmosphere, a series of scientific data processors are being developed in the framework of the TIMELINE project. The archive of DLR ranges back to the 80ies. One of the data processors is SurfTemp, which processes L2 LST and emissivity datasets from AVHRR L1b data. The development of the data processor included the selection of statistical procedures suitable for time series processing, including four mono-window and six split window algorithms. For almost all of these algorithms, new constants were generated, which better account for different atmospheric and geometric acquisition situations. The selection of optimal algorithms for SurfTemp is based on a round robin approach, in which the selected mono-window and split window algorithms are tested on the basis of a large number of TOA radiance/LST pairs, which were generated using a radiative transfer model and the SeeBorV5 profile database. The original LSTs are thereby compared to the LSTs derived from the TOA radiances using the mono- and split window algorithms. The algorithm comparison includes measures of precision, as well as the sensitivity of a method to the accuracy of its input data. The results of the round robin are presented, as well as the implementation of selected algorithms into SurfTemp. Further, first cross-validation results between the AVHRR LST and MODIS LST are shown.

  10. Online Detection of Mixed Layer Depth for Autonomous Underwater Vehicles

    NASA Astrophysics Data System (ADS)

    Chu, S.; Estlin, T.; Castano, R.; Woodward, G.; Gierach, M. M.; Thompson, A. F.; Schaffer, S.

    2015-12-01

    The accurate determination of the mixed layer depth (MLD) plays a crucial role in studying ocean dynamics and climate change. Various methods to estimate MLD have been proposed [1, 2]. However there is no current consensus on the best model, which leads to large uncertainty in the estimation. The variability, coupled with the complexity of physical, chemical and biological processes involved and the uncertainty and instabilities of the upper ocean surface, makes estimating MLD a challenging task. MLD varies significantly, even across a small spatial area (< 10km), and this depth is fluctuating, even over a short period of time (< 24 hrs), depending on the season. This abstract describes our proposed online algorithm for detecting mixed layer depth that would operate onboard an autonomous underwater vehicle (AUV). Using an online method permits a more adaptive approach to estimating MLD. Our proposed algorithm is based on an ensemble approach, which includes data mining techniques for real-time peak and change detection, learned seasonal variability profile, combined with MLD estimation criteria in [1]. In this study, we analyze measurements using glider data collected from the OSMOSIS (Ocean Surface Mixing, Ocean Submesoscale Interaction Study) project, concatenated into a year-long time series [3]. The glider data consists of nine full-depth moorings, which were deployed in a 15 km by 15 km box at the Porcupine Abyssal Plain in the northeast Atlantic, centered at 16.2°W, 48.7°N. Our algorithm utilizes direct measurements of salinity, temperature, depth and time and the design is based on the spatial and temporal variability of MLD learned. We will present our initial work on tracking the MLD based on real-time simulations using the OSMOSIS glider data and discussed for the case of deploying on a single AUV. Using an online algorithm for estimating MLD in-situ enables the system to rapidly adapt to the variability in a real-world environment and also allows for

  11. Curie point depth from spectral analysis of aeromagnetic data for geothermal reconnaissance in Afghanistan

    NASA Astrophysics Data System (ADS)

    Saibi, H.; Aboud, E.; Gottsmann, J.

    2015-11-01

    The geologic setting of Afghanistan has the potential to contain significant mineral, petroleum and geothermal resources. However, much of the country's potential remains unknown due to limited exploration surveys. Here, we present countrywide aeromagnetic data to estimate the Curie point depth (CPD) and to evaluate the geothermal exploration potential. CPD is an isothermal surface at which magnetic minerals lose their magnetization and as such outlines an isotherm of about 580 °C. We use spectral analysis on the aeromagnetic data to estimate the CPD spatial distribution and compare our findings with known geothermal fields in the western part of Afghanistan. The results outline four regions with geothermal potential: 1) regions of shallow Curie point depths (∼16-21 km) are located in the Helmand basin. 2) regions of intermediate depths (∼21-27 km) are located in the southern Helmand basin and the Baluchistan area. 3) Regions of great depths (∼25-35 km) are located in the Farad block. 4) Regions of greatest depths (∼35-40 km) are located in the western part of the northern Afghanistan platform. The deduced thermal structure in western Afghanistan relates to the collision of the Eurasian and Indian plates, while the shallow CPDs are related to crustal thinning. This study also shows that the geothermal systems are associated with complex magmatic and tectonic association of major intrusions and fault systems. Our results imply geothermal gradients ranging from 14 °C/km to 36 °C/km and heat-flow values ranging from 36 to 90 mW/m2 for the study area.

  12. Geothermal research on the 2.5 km deep COSC-1 drillhole, Central Sweden

    NASA Astrophysics Data System (ADS)

    Pascal, Christophe; Beltrami, Hugo; Daly, Stephen; Juhlin, Christopher; Kukkonen, Ilmo; Long, Mike; Rath, Volker; Renner, Joerg; Schwarz, Gerhard; Sundberg, Jan

    2015-04-01

    The scientific drilling project "Collisional Orogeny in the Scandinavian Caledonides" (COSC), supported by ICDP and the Swedish Research Council, involves the drilling of two boreholes through carefully selected sections of the Paleozoic Caledonian orogen in Central Sweden. COSC-1, the first of the two planned boreholes, was drilled and fully cored down to 2.5 km depth during spring and summer 2014 near the town of Åre. The COSC working group is organised around six thematic teams including us, the geothermal team. The major objectives of the COSC geothermal team are: a) to contribute to basic knowledge about the thermal regime of Palaeozoic orogenic belts, ancient shield areas and high heat-producing plutons; b) to refine knowledge on climate change at high latitudes (i.e. Scandinavia), including historical global changes, recent palaeoclimate development (since last ice age) and expected future trends; c) to determine the vertical variation of the geothermal gradient, heat flow and thermal properties down to 2.5 km, and to determine the required corrections for shallow (< 1 km) heat flow data; d) to explore the geothermal potential of the Åre-Järpen area; e) to explore to what degree the conductive heat transfer is affected by groundwater flow in the uppermost crust and f) to evaluate the heat generation input and impact from the basement and the alum shales. To reach these targets the following tasks were carried out or are planned: 1) heat flow predictions from shallow boreholes; 2) geophysical logging; 3) analyses of logs and well tests; (3) determination of rock thermal properties on core samples; 4) determination of heat generation rates from radiometric and geochemical studies; 5) fracture characterisation for permeability and convective heat flow estimations; 6) analysis of convective signals; 7) analysis of paleoclimatic signals; 8) heat flow modelling and evaluation of geothermal potential and 9) Fennoscandia heat flow map compilation. The purpose of

  13. Diffusive modeling of global river and floodplain dynamics based on 1km-resolution DEM

    NASA Astrophysics Data System (ADS)

    Yamazaki, D.; Kanae, S.; Oki, T.

    2009-12-01

    Terrestrial water circulation is important both as a component of the climate system and as a freshwater supplying system for human beings. Recent advances in remote sensing have achieved global-scale observation of surface water storage and movement from satellites (e.g. inundated area extent by microwave imagers, terrestrial water storage by GRACE, water surface altitude and river discharge possibly by SWOT). On the other hand, global river routing models, which are practically the only available tool for simulating terrestrial water circulation, have not adequately represented the physical mechanism of terrestrial water storage and movement, such as floodplain inundation dynamics regulated by much smaller-scale topography than global model resolution. A newly developed global river routing model named “Catchment-based Macro-scale Floodplain model” (CaMa-Flood) overcomes this drawback by detailed representation of sub-grid-scale topography (ex. river channel cross-section, catchment boundaries, and floodplain elevation profile). These sub-grid features regulating surface water dynamics are objectively parameterized based on 1km-resolution global DEM and flow direction map. This approach enables explicit prediction of surface water altitude, which is essential for diffusive wave modeling of floodplain inundation dynamics. Thus, CaMa-Flood is expected to simulate not only realistic river discharge but also water depth, inundated area extent, and surface water storage. Improvements from previous global river routing models achieved by CaMa-Flood are summarized as follows: (1) objective parameterization of sub-grid topographies using 1km-resolution datasets, (2) explicit representation of floodplain inundation dynamics, (3) diffusive wave modeling for flow computation instead of kinematic wave modeling, and (4) two dimensional expression of inundated area extent which can be validated against satellite observations. Ability of CaMa-Flood is tested by comparing

  14. Foundation Depth for Bridge Piers

    NASA Astrophysics Data System (ADS)

    Veerappadevaru, G.; Gangadharaiah, T.; Jagadeesh, T. R.

    2013-09-01

    The safety of bridge piers built in rivers having the bed is one of the prime aspects in the study of scouring process around bridge piers. The stability of bridge piers depends on the depth of foundation provided below maximum scour level. The stability analysis of bridge piers is carried based on moment of forces acting on the caisson pier when the pier slides and tilts slightly in downstream from its position. The experiments are conducted for three pier shapes on two sediment beds and for different flow conditions. The curves indicating the stability limits are compared with Lacey's recommendations which are used in present day practice in India. The analysis presented here indicates that the Lacey's recommendation for railway bridges is safe and for some cases of the road bridges depends on grip length, angle of tilt and weight of caisson.

  15. Aeration equipment for small depths

    NASA Astrophysics Data System (ADS)

    Sluše, Jan; Pochylý, František

    2015-05-01

    Deficit of air in water causes complications with cyanobacteria mainly in the summer months. Cyanobacteria is a bacteria that produces poison called cyanotoxin. When the concentration of cyanobacteria increases, the phenomena "algal bloom" appears, which is very toxic and may kill all the organisms. This article describes new equipment for aeration of water in dams, ponds and reservoirs with small depth. This equipment is mobile and it is able to work without any human factor because its control is provided by a GPS module. The main part of this equipment consists of a floating pump which pumps water from the surface. Another important part of this equipment is an aerator where water and air are blended. Final aeration process runs in the nozzles which provide movement of all this equipment and aeration of the water. Simulations of the flow are solved by multiphase flow with diffusion in open source program called OpenFOAM. Results will be verified by an experiment.

  16. Influence of depth and sampling time on bacterial community structure in an upland grassland soil.

    PubMed

    Griffiths, Robert I; Whiteley, Andrew S; O'Donnell, Anthony G; Bailey, Mark J

    2003-02-01

    Abstract Temporal and spatial variation of soil bacterial communities was evaluated with both molecular and metabolic profiling techniques. Soil cores (20 cm deep) were taken from an upland grassland in the Scottish Borders (UK) over 3 days in July 1999, and on single days in October 1999, April 2000, and August 2000. Cores were separated into four 5-cm depths to examine vertical spatial distribution. The 0-5-, 5-10- and 10-15-cm samples represented organic horizons whilst the 15-20-cm depths were from a mineral horizon. The potential metabolic activities were analysed using BIOLOG-GN plates, whereas genotypic diversity was evaluated using molecular profiling of amplified 16S rRNA and 16S rDNA gene fragments (denaturing gradient gel electrophoresis (DGGE)). BIOLOG-GN analysis revealed decreased substrate utilisation in the lowest depths, which was coupled with changes in the DNA and RNA DGGE profiles. Seasonal variation was pronounced in the 5-10-cm and 10-15-cm organic horizons for the July samplings whilst the 15-20-cm depths appeared more stable. Potential factors influencing the observed changes in bacterial communities resulting from soil depth and sampling time are discussed.

  17. Effect of sowing depth on performance of Quercus castaneifolia seedling at different levels of canopy cover.

    PubMed

    Jalali; Gh, A; Ali-Arab, A R; Tabari, M; Akbarinia, M; Hosseini, S M

    2007-04-01

    Due to failure of oak (Quercus castaneifolia C.A. Meyer) natural regeneration, investigation on the best acorn sowing depth of this species under different levels of canopy cover is an important consideration in the Caspian forests, north of Iran. For this purpose, a study site with north-facing slope, clay-loam soil and 260-280 m a.s.l. was chosen in a mixed oak forest. The experiment was conducted as a Complete Randomized Split Plot Design (CRSPD) and the measurements made in one growing season in nine fenced circular 1000 m2 plots with three canopy densities (25, 50 and 75%) at three soil depths (5, 10 and 15 cm). The results revealed that under all canopy densities the maximum seedling emergence occurred at 5 cm depth. The highest emergence rate was appeared in June and the lowest in October. Neither canopy density nor sowing depth did prominently reduce seedling establishment, but a high quotient of mortality likely could be attributed to rodent populations, particularly Hystrix indica. Under all canopies, ground line diameter decreased with increasing sowing depth, the biggest being at 5 cm depth. Neither canopy density nor sowing depth influenced the seedling height. It can be concluded that the best performance of Q. castaneifolia seedling occurs at 5 cm sowing depth and 25% canopy cover.

  18. 21 CFR 73.3120 - 16,17-Dimethoxydinaphtho [1,2,3-cd:3′,2′,1′-lm] perylene-5,10-dione.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false 16,17-Dimethoxydinaphtho perylene-5,10-dione. 73.3120 Section 73.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3120...

  19. 21 CFR 73.3120 - 16,17-Dimethoxydinaphtho [1,2,3-cd:3′,2′,1′-lm] perylene-5,10-dione.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false 16,17-Dimethoxydinaphtho perylene-5,10-dione. 73.3120 Section 73.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3120...

  20. 21 CFR 73.3120 - 16,17-Dimethoxydinaphtho [1,2,3-cd:3′,2′,1′-lm] perylene-5,10-dione.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false 16,17-Dimethoxydinaphtho perylene-5,10-dione. 73.3120 Section 73.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3120...

  1. 112 Gb/s PM-QPSK transmission up to 6000 km with 200 km amplifier spacing and a hybrid fiber span configuration.

    PubMed

    Downie, John D; Hurley, Jason; Cartledge, John; Bickham, Scott; Mishra, Snigdharaj

    2011-12-12

    We demonstrate transmission of 112 Gb/s PM-QPSK signals over a system with 200 km span lengths. Amplification is provided by hybrid backward-pumped Raman/EDFA amplifiers and reach lengths up to 6000 km for an 8 channel system and 5400 km for a 32 channel system are shown. As a means of maximizing OSNR, a simple hybrid fiber span configuration is used that combines two ultra-low loss fibers, one having very large effective area.

  2. A 5000km2 data set along western Great Bahama Bank illustrates the dynamics of carbonate slope deposition

    NASA Astrophysics Data System (ADS)

    Schnyder, Jara S. D.; Jo, Andrew; Eberli, Gregor P.; Betzler, Christian; Lindhorst, Sebastian; Schiebel, Linda; Hebbeln, Dierk; Wintersteller, Paul; Mulder, Thierry; Principaud, Melanie

    2014-05-01

    An approximately 5000km2 hydroacoustic and seismic data set provides the high-resolution bathymetry map of along the western slope of Great Bahama Bank, the world's largest isolated carbonate platform. This large data set in combination with core and sediment samples, provides and unprecedented insight into the variability of carbonate slope morphology and the processes affecting the platform margin and the slope. This complete dataset documents how the interplay of platform derived sedimentation, distribution by ocean currents, and local slope and margin failure produce a slope-parallel facies distribution that is not governed by downslope gradients. Platform-derived sediments produce a basinward thinning sediment wedge that is modified by currents that change directions and strength depending on water depth and location. As a result, winnowing and deposition change with water depth and distance from the margin. Morphological features like the plunge pool and migrating antidunes are the result of currents flowing from the banktop, while the ocean currents produce contourites and drifts. These continuous processes are punctuated by submarine slope failures of various sizes. The largest of these slope failures produce several hundred of km2 of mass transport complexes and could generate tsunamis. Closer to the Cuban fold and thrust belt, large margin collapses pose an equal threat for tsunami generation. However, the debris from margin and slope failure is the foundation for a teeming community of cold-water corals.

  3. Imaging widespread seismicity at midlower crustal depths beneath Long Beach, CA, with a dense seismic array: Evidence for a depth-dependent earthquake size distribution

    NASA Astrophysics Data System (ADS)

    Inbal, Asaf; Clayton, Robert W.; Ampuero, Jean-Paul

    2015-08-01

    We use a dense seismic array composed of 5200 vertical geophones to monitor microseismicity in Long Beach, California. Poor signal-to-noise ratio due to anthropogenic activity is mitigated via downward-continuation of the recorded wavefield. The downward-continued data are continuously back projected to search for coherent arrivals from sources beneath the array, which reveals numerous, previously undetected events. The spatial distribution of seismicity is uncorrelated with the mapped fault traces, or with activity in the nearby oil-fields. Many events are located at depths larger than 20 km, well below the commonly accepted seismogenic depth for that area. The seismicity exhibits temporal clustering consistent with Omori's law, and its size distribution obeys the Gutenberg-Richter relation above 20 km but falls off exponentially at larger depths. The dense array allows detection of earthquakes two magnitude units smaller than the permanent seismic network in the area. Because the event size distribution above 20 km depth obeys a power law whose exponent is near one, this improvement yields a hundred-fold decrease in the time needed for effective characterization of seismicity in Long Beach.

  4. Seasonal variability of aerosol optical depth over Indian subcontinent

    USGS Publications Warehouse

    Prasad, A.K.; Singh, R.P.; Singh, A.; Kafatos, M.

    2005-01-01

    Ganga basin extends 2000 km E-W and about 400 km N-S and is bounded by Himalayas in the north. This basin is unequivocally found to be affected by high aerosols optical depth (AOD) (>0.6) throughout the year. Himalayas restricts movement of aerosols toward north and as a result dynamic nature of aerosol is seen over the Ganga basin. High AOD in this region has detrimental effects on health of more than 460 million people living in this part of India besides adversely affecting clouds formation, monsoonal rainfall pattern and Normalized Difference Vegetation Index (NDVI). Severe drought events (year 2002) in Ganga basin and unexpected failure of monsoon several times, occurred in different parts of Indian subcontinent. Significant rise in AOD (18.7%) over the central part of basin (Kanpur region) have been found to cause substantial decrease in NDVI (8.1%) since 2000. A negative relationship is observed between AOD and NDVI, magnitude of which differs from region to region. Efforts have been made to determine general distribution of AOD and its dominant departure in recent years spatially using Moderate Resolution Imaging Spectroradiometer (MODIS) data. The seasonal changes in aerosol optical depth over the Indo-Gangetic basin is found to very significant as a result of the increasing dust storm events in recent years. ?? 2005 IEEE.

  5. Visual Cues for Enhancing Depth Perception.

    ERIC Educational Resources Information Center

    O'Donnell, L. M.; Smith, A. J.

    1994-01-01

    This article describes the physiological mechanisms involved in three-dimensional depth perception and presents a variety of distance and depth cues and strategies for detecting and estimating curbs and steps for individuals with impaired vision. (Author/DB)

  6. Modification of closure depths by synchronisation of severe seas and high water levels

    NASA Astrophysics Data System (ADS)

    Soomere, Tarmo; Männikus, Rain; Pindsoo, Katri; Kudryavtseva, Nadezhda; Eelsalu, Maris

    2016-10-01

    The closure depth indicates the depth down to which storm waves maintain a universal shape of the coastal profile. It is thus a key parameter of the coastal zones for a variety of engineering and ecosystem applications. Its values are commonly estimated with respect to the long-term mean water level. The present study re-evaluates closure depths for microtidal water bodies where the wave loads are highly correlated with the course of the water level. The test area is the eastern Baltic Sea. The closure depth is calculated for the eastern Baltic Sea coast with a resolution of 5.5 km and the vicinity of Tallinn Bay with a resolution of 0.5 km. While the classic values of closure depth are extracted from statistics of the roughest seas, the present analysis is based on single values of a proxy of the instantaneous closure depth. These values are evaluated from numerically simulated time series of wave properties and water levels. The water level-adjusted closure depths are almost equal to the classic values at the coasts of Lithuania but are up to 10% smaller at the Baltic Proper coasts of Latvia and Estonia. The difference is up to 20% in bayheads of the Gulf of Finland.

  7. Uterine caliper and depth gauge

    DOEpatents

    King, Loyd L.; Wheeler, Robert G.; Fish, Thomas M.

    1977-01-01

    A uterine caliper and sound consisting of an elongated body having outwardly biased resilient caliper wings and a spring-loaded slidable cervical stop. A slide on the body is operatively connected to the wings by a monofilament and operates with respect to a first scale on the body as a width indicator. A rod extending longitudinally on the body is connected to the cervical stop and cooperates with a second scale on the body as a depth indicator. The instrument can be positioned to measure the distance from the outer cervical ostium to the fundus, as read on said second scale. The wings may be allowed to open by moving the slide, and when the wings engage the utero-tubal junctions, the width may be read on said first scale. By adjustment of the caliper wings the instrument may be retracted until the resistance of the inner ostium of the cervix is felt, enabling the length of the cervical canal to be read directly by the position of the longitudinal indicator rod with respect to said second scale. The instrument may be employed to measure the width of the uterine cavity at any position between the inner ostium of the cervix and the fundus.

  8. Mantle transition zone structure beneath the Changbai volcano: Insight into deep slab dehydration and hot upwelling near the 410 km discontinuity

    NASA Astrophysics Data System (ADS)

    Tian, You; Zhu, Hongxiang; Zhao, Dapeng; Liu, Cai; Feng, Xuan; Liu, Ting; Ma, Jincheng

    2016-08-01

    We study the detailed mantle transition zone structure beneath the active Changbai intraplate volcano in Northeast China by using a receiver-function method. A total of 3005 teleseismic receiver functions recorded by 70 broadband stations are obtained by using a common-conversion-point stacking method. For conducting the time-to-depth conversion, we use a three-dimensional velocity model of the study region so as to take into account the influence of structural heterogeneities. Our results reveal significant depth variations of the 410, 520, and 660 km discontinuities. A broad depression of the 410 km discontinuity and a low-velocity anomaly are revealed beneath the Changbai volcano, which may reflect a large-scale hot mantle upwelling around the 410 km discontinuity with a positive Clapeyron slope. The 520 km discontinuity is identified clearly, and its uplift occurs above the stagnant Pacific slab. We also find a prominent depression of the 660 km discontinuity, which is elongated along the trend of deep earthquake clusters in a range of 39°N-44°N latitude, and the depression area has a lateral extent of about 400 km. Because the 520 and 660 km discontinuities correspond to positive and negative Clapeyron slopes, respectively, we think that the 520 uplift and the 660 depression are caused by the cold subducting Pacific slab. A part of the Pacific slab may have penetrated into the lower mantle and so caused the large-scale 660 depression in front of the deep earthquake clusters. Our results also reveal a part of the upper boundary of the subducting Pacific slab in the mantle transition zone.

  9. Implications of Depth Determination from Second Moving Average Residual Magnetic Anomalies on Mars

    NASA Astrophysics Data System (ADS)

    Essa, K. S.; Kletetschka, G.

    2014-12-01

    Mars total magnetic data obtained by Mars Global Surveyor mission from 400 km altitude were processed using a second moving average method (SMAM) to estimate the depth of the buried sources. Five profiles were chosen across major magnetic areas. Each profile was subjected to a separation technique using the SMAM. Second moving average residual anomalies (SMARA) were obtained from magnetic data using filters of successive spacing. The depth estimate is monitored by the standard deviation of the depths determined from all SMARA for various value of the shape factor (SF) that includes dike, cylinder, and sphere. The standard deviation along with depth estimate is considered to be a new criterion for determining the correct depth and shape of the buried structures on Mars.

  10. Variation of depth to the brittle-ductile transition due to cooling of a midcrustal intrusion.

    USGS Publications Warehouse

    Gettings, M.E.

    1988-01-01

    The depth to the brittle-ductile transition in the crust is often defined by the intersection of a shear resistance relation in the brittle upper crust that increases linearly with depth and a power law relation for ductile flow in the lower crust that depends strongly on T. Transient variation of this depth caused by a magmatic intrusion at a depth near the regional transition can be modelled by a heat conduction model for a rectangular parallelepiped superimposed on a linear geothermal gradient. When parameters appropriate for the southeastern US are used, a moderate-sized intrusion is found to decrease the transition depth by as much as 7 km; significant variations last approx 10 m.y. Since the base of the seismogenic zone is identified with the brittle-ductile transition, these results imply that intrusions of late Tertiary age or younger could be important sources of clustered seismicity. -A.W.H.

  11. Microorganisms persist at record depths in the subseafloor of the Canterbury Basin

    PubMed Central

    Ciobanu, Maria-Cristina; Burgaud, Gaëtan; Dufresne, Alexis; Breuker, Anja; Rédou, Vanessa; Ben Maamar, Sarah; Gaboyer, Frédéric; Vandenabeele-Trambouze, Odile; Lipp, Julius Sebastian; Schippers, Axel; Vandenkoornhuyse, Philippe; Barbier, Georges; Jebbar, Mohamed; Godfroy, Anne; Alain, Karine

    2014-01-01

    The subsurface realm is colonized by microbial communities to depths of >1000 meters below the seafloor (m.b.sf.), but little is known about overall diversity and microbial distribution patterns at the most profound depths. Here we show that not only Bacteria and Archaea but also Eukarya occur at record depths in the subseafloor of the Canterbury Basin. Shifts in microbial community composition along a core of nearly 2 km reflect vertical taxa zonation influenced by sediment depth. Representatives of some microbial taxa were also cultivated using methods mimicking in situ conditions. These results suggest that diverse microorganisms persist down to 1922 m.b.sf. in the seafloor of the Canterbury Basin and extend the previously known depth limits of microbial evidence (i) from 159 to 1740 m.b.sf. for Eukarya and (ii) from 518 to 1922 m.b.sf. for Bacteria. PMID:24430485

  12. Variation of Fracturing Pressures with Depth Near the Valles Caldera

    SciTech Connect

    Dash, Zora; Murphy, Hugh

    1983-12-15

    Hydraulic Fracturing at the Fenton Hill Hot Dry Rock Geothermal site near the Valles Caldera has yielded fracturing pressures from 14 to 81 MPa (2030 to 11,750 psi) at depths ranging from 0.7 to 4.4 km (2250 to 14,400 ft). This data can be fit to a fracture gradient of 19 MPa/km (0.84 psi/ft), except for an anomalous region between 2.6 to 3.2 km where fracturing pressures are about 20 MPa lower than estiamted using the above gradient. This anomaly coincides with a biotite granodiorite intrusive emplaced into a heterogeneous jointed metamorphic complex comprised of gneisses, schists and metavolcanic rocks. Microseismic events detected with sensitive downhole geophones suggest that shear failure is an important process during hydraulic fracturing of such jointed rock. Consequently the usual relation between minimum earth stress and fracture opening pressure, based upon classic tensile failure, cannot be used apriori; fracture opening pressure is instead a complex function of joint orientation and all three components of principal earth stress.

  13. Depth enhanced and content aware video stabilization

    NASA Astrophysics Data System (ADS)

    Lindner, A.; Atanassov, K.; Goma, S.

    2015-03-01

    We propose a system that uses depth information for video stabilization. The system uses 2D-homographies as frame pair transforms that are estimated with keypoints at the depth of interest. This makes the estimation more robust as the points lie on a plane. The depth of interest can be determined automatically from the depth histogram, inferred from user input such as tap-to-focus, or selected by the user; i.e., tap-to-stabilize. The proposed system can stabilize videos on the fly in a single pass and is especially suited for mobile phones with multiple cameras that can compute depth maps automatically during image acquisition.

  14. Is visual short-term memory depthful?

    PubMed

    Reeves, Adam; Lei, Quan

    2014-03-01

    Does visual short-term memory (VSTM) depend on depth, as it might be if information was stored in more than one depth layer? Depth is critical in natural viewing and might be expected to affect retention, but whether this is so is currently unknown. Cued partial reports of letter arrays (Sperling, 1960) were measured up to 700 ms after display termination. Adding stereoscopic depth hardly affected VSTM capacity or decay inferred from total errors. The pattern of transposition errors (letters reported from an uncued row) was almost independent of depth and cue delay. We conclude that VSTM is effectively two-dimensional. PMID:24491386

  15. Healthy Homes/Healthy Kids: A Randomized Trial of a Pediatric Primary Care Based Obesity Prevention Intervention for At-Risk 5-10 Year Olds

    PubMed Central

    Sherwood, Nancy E.; Levy, Rona L.; Langer, Shelby L.; Senso, Meghan M.; Crain, A. Lauren; Hayes, Marcia G.; Anderson, Julie D.; Seburg, Elisabeth M.; Jeffery, Robert W.

    2014-01-01

    Pediatric primary care is an important setting in which to address obesity prevention, yet relatively few interventions have been evaluated and even fewer have been shown to be effective. The development and evaluation of cost-effective approaches to obesity prevention that leverage opportunities of direct access to families in the pediatric primary care setting, overcome barriers to implementation in busy practice settings, and facilitate sustained involvement of parents is an important public health priority. The goal of the Healthy Homes/Healthy Kids (HHHK 5-10) randomized controlled trial is to evaluate the efficacy of a relatively low-cost primary care-based obesity prevention intervention aimed at 5 to 10 year old children who are at risk for obesity. Four hundred twenty one parent/child dyads were recruited and randomized to either the obesity prevention arm or a contact control condition that focuses on safety and injury prevention. The HHHK 5-10 obesity prevention intervention combines brief counseling with a pediatric primary care provider during routine well-child visits and follow-up telephone coaching that supports parents in making home environmental changes to support healthful eating, activity patterns, and body weight. The contact control condition combines the same provider counseling with telephone coaching focused on safety and injury prevention messages. This manuscript describes the study design and baseline characteristics of participants enrolled in the HHHK 5-10 trial. PMID:23816490

  16. Healthy Homes/Healthy Kids: a randomized trial of a pediatric primary care-based obesity prevention intervention for at-risk 5-10 year olds.

    PubMed

    Sherwood, Nancy E; Levy, Rona L; Langer, Shelby L; Senso, Meghan M; Crain, A Lauren; Hayes, Marcia G; Anderson, Julie D; Seburg, Elisabeth M; Jeffery, Robert W

    2013-09-01

    Pediatric primary care is an important setting in which to address obesity prevention, yet relatively few interventions have been evaluated and even fewer have been shown to be effective. The development and evaluation of cost-effective approaches to obesity prevention that leverage opportunities of direct access to families in the pediatric primary care setting, overcome barriers to implementation in busy practice settings, and facilitate sustained involvement of parents is an important public health priority. The goal of the Healthy Homes/Healthy Kids (HHHK 5-10) randomized controlled trial is to evaluate the efficacy of a relatively low-cost primary care-based obesity prevention intervention aimed at 5 to 10 year old children who are at risk for obesity. Four hundred twenty one parent/child dyads were recruited and randomized to either the obesity prevention arm or a Contact Control condition that focuses on safety and injury prevention. The HHHK 5-10 obesity prevention intervention combines brief counseling with a pediatric primary care provider during routine well child visits and follow-up telephone coaching that supports parents in making home environmental changes to support healthful eating, activity patterns, and body weight. The Contact Control condition combines the same provider counseling with telephone coaching focused on safety and injury prevention messages. This manuscript describes the study design and baseline characteristics of participants enrolled in the HHHK 5-10 trial. PMID:23816490

  17. Weekly cycle of magnetic characteristics of the daily PM2.5 and PM2.5-10 in Beijing, China

    NASA Astrophysics Data System (ADS)

    Shi, Meinan; Wu, Huaichun; Zhang, Shihong; Li, Haiyan; Yang, Tianshui; Liu, Wei; Liu, He

    2014-12-01

    In recent years, Beijing has been shown to suffer one of the most serious air pollution problems of any major world city. The concentrations of particulate matter (PM) pollutants, PM2.5-10 and PM2.5, are commonly used as air pollution indexes. We conducted a detailed environmental magnetism study to investigate possible sources of air pollution in Beijing, China, using 283 pairs of the PM2.5 and PM2.5-10 samples collected daily from July 2010 to June 2011. Rock magnetic measurements, including magnetic susceptibility, anhysteretic remanent magnetization, isothermal remanent magnetization, saturation isothermal remanent magnetization, hysteresis loops, first-order reversal curves (FORCs), and thermomagnetism, indicate that the main magnetic mineral is low-coercivity pseudo-single domain (PSD) magnetite. Scanning electron microscope (SEM) observations and energy dispersive X-ray spectroscopy (EDS) analyses on the PM indicate that the major magnetic phase is coarse-grained magnetite, which is most likely from automobile exhausts and braking system debris. Magnetic parameters of PM2.5 and PM2.5-10 show significant seasonal patterns that may be attributed to domestic heating enhancing magnetization of the PM during late autumn to early spring. Power spectral analyses and box-whisker plots indicate that the magnetic parameters have strong weekly variations that may be due to traffic emissions. These results indicate that magnetic parameters can be used as efficient proxies for monitoring Beijing's air pollution, and that the atmospheric environment may be improved by controlling vehicle emissions.

  18. Developing Knowledge Management (KM): Contributions by Organizational Learning and Total Quality Management (TQM)

    ERIC Educational Resources Information Center

    Hung, Richard Yu-Yuan; Lien, Bella Ya-Hui

    2005-01-01

    Knowledge management is an integral business function for many organizations to manage intellectual resources effectively. From a resource-based perspective, organizational learning and TQM are antecedents that are closely related to KM. The purposes of this study were to explain the contents of KM, and explore the relationship between KM-related…

  19. Event Screening Using a Cepstral F-Statistic Technique to Identify Depth Phases

    NASA Astrophysics Data System (ADS)

    Bonner, J. L.; Reiter, D. T.; Shumway, R. H.

    2001-05-01

    The depth of a seismic event is one of the most important criteria for screening events as either explosions or earthquakes. Unfortunately, the depth is also notoriously difficult to accurately determine. Some of the methods used to determine focal depth include waveform modeling, beamforming and cepstral methods for detecting depth phases such as pP and sP. To improve depth estimation using cepstral methods we focused on three primary goals: (1) formulating a method for determining the statistical significance of peaks in the cepstrum, (2) testing the method on synthetic data as well as earthquake data with well-determined hypocenters, and (3) evaluating the method as an operational analysis tool for determining event depths using varied datasets at both teleseismic and regional distances. We have formulated a cepstral F-statistic by using a classical approach to detecting a signal in a number of stationarily correlated time series. The method is particularly suited for regional array analysis; however, the method can also be applied to three-component data. Tests on synthetic data show the method works best when the P wave arrival has a signal-to-noise ratio (SNR) greater than between 8 and 10 with the depth phase exhibiting a SNR greater than between 2 and 4. These requirements in SNR were validated using events from the Hindu Kush region of Afghanistan with well-determined depths as recorded on arrays at teleseismic distances. To test the operational capabilities of this method as a tool for event screening at a data center, we analyzed 61 events located by the pIDC and/or the National Earthquake Information Center (NEIC). Our method determined statistically significant depths for 41 of 61 events with 10 of the events having low SNR at the recording arrays, while another 10 were either too shallow for analysis or did not exhibit depth phases. The method determined depths between 12 and 90 km for 7 of 17 events, which the pIDC had fixed to 0 km. The scatter

  20. Depth dependence of anisotropy of Earth's inner core

    NASA Astrophysics Data System (ADS)

    Song, Xiaodong; Helmberger, Don V.

    1995-06-01

    Both body wave (PKP) travel times (Creager, 1992; Song and Helmberger, 1993a; McSweeney and Creager, 1993; Shearer, 1994) and fits to the splitting of core modes (Tromp, 1993) show general agreement that the top 300 km of inner core is very anisotropic. The anisotropy displays axial symmetry around the Earth's spin axis, with the polar direction 3% faster than the equatorial direction. One key problem now is the depth dependence of the inner core anisotropy. Here we extend our polar path studies to include both long-period and short-period modeling for the PKP phases at ranges 120° to 173°. Arrivals from the top of the inner core (PKIKP) and reflections from the inner core boundary (PKiKP) can be observed distinctly in short-period records at ranges 130° to 140° and as waveform distortions in the long-period records at ranges 130° to 146°. These waveforms provide a new set of data for examining the topmost 150 km of the inner core, which is not well sampled by the previous body wave travel times. Record sections of waves traversing the inner core nearly parallel to the Earth's spin axis (polar paths) from three events, two beneath the South Sandwich Islands and one along the Macquarie Ridge, recorded at World Wide Standardized Seismograph Network, Canadian Network, and Long Range Seismic Measurements stations are analyzed. Our results suggest that the top 150 km of the inner core is only weakly anisotropic (less than 1%), with strong evidence indicating that the top 60 km is not anisotropic at all.

  1. A deformation rig for synchrotron microtomography studies of geomaterials under conditions down to 10 km depth in the Earth.

    PubMed

    Renard, François; Cordonnier, Benoit; Dysthe, Dag K; Boller, Elodie; Tafforeau, Paul; Rack, Alexander

    2016-07-01

    A hard X-ray transparent triaxial deformation apparatus, called HADES, has been developed by Sanchez Technologies and installed on the microtomography beamline ID19 at the European Radiation Synchrotron Facility (ESRF). This rig can be used for time-lapse microtomography studies of the deformation of porous solids (rocks, ceramics, metallic foams) at conditions of confining pressure to 100 MPa, axial stress to 200 MPa, temperature to 250°C, and controlled aqueous fluid flow. It is transparent to high-energy X-rays above 60 keV and can be used for in situ studies of coupled processes that involve deformation and chemical reactions. The rig can be installed at synchrotron radiation sources able to deliver a high-flux polychromatic beam in the hard X-ray range to acquire tomographic data sets with a voxel size in the range 0.7-6.5 µm in less than two minutes. PMID:27359153

  2. Discovery of 3 km long seafloor fracture system in the Central North Sea

    NASA Astrophysics Data System (ADS)

    Pedersen, R. B.; Blomberg, A.; Landschulze, K.; Baumberger, T.; Økland, I.; Reigstad, L.; Gracias, N.; Mørkved, P. T.; Stensland, A.; Lilley, M. D.; Thorseth, I. H.

    2013-12-01

    We have discovered a 3 km long seafloor fracture system in the Central North Sea (block 16/4). The discovery was made using a synthetic aperture sonar (HISAS) mounted on a Kongsberg Hugin AUV. The surface expression of the structure - named the Hugin Fracture - changes along the strike and it is characterized by: 1) linear; 2) en echelon; and 3) branching segments. Ring-structures, that typically are 5-10 meters across, are common along the feature. Micro-bathymetry acquired using the HISAS system demonstrates that sub-meter scale elevation changes occur across the fracture. Microbial mats occur along different parts of the structure showing that active seepage is taking place. AUV based photo-imaging of parts of the structure shows that the microbial mats predominantly are associated with ring structures and some of the linear fracture segments. Sediment pore waters extracted from push cores show Na, Cl and Mg contents that are 10-15% lower compared to background pore fluid concentrations. This points towards a fresh water input. The fracture pore fluid compositions are also characterized by elevated methane, ammonium and hydrogen sulphide contents compared to the background seawater. The presence of these volatiles is likely caused by subsurface microbial activity, and carbon isotope analyses confirm a biological source of the detected methane. However, the presence of ethane (CH4/C2H6 of 126) indicates a small input of a thermogenic carbon to these fluids. Subsurface imaging using a hull mounted parametric sub bottom profiler reveal Holocene stratified sediments overlying quaternary moraine in the area. The sub bottom profiler data show sub-meter scale vertical movements along the fracture. Associated with the structures are small bright spots that may reflect gas accumulations. No deep-seated fault system is apparent below the fracture in 3D seismic data from the area. However, the 3D seismic data show that the structure is located above the boundary of a

  3. Investigations on the germination depth of Johnson grass (Sorghum halepense [L.] pers).

    PubMed

    Tóth, V; Lehoczky, E

    2006-01-01

    The aim of our experiment was to gain data about the germination depth of Johnson grass, and to investigate the dynamics of germination at different sowing depths. These investigations have great importance in respect of effective weed control. The experiments were carried out in the summer of 2005, using pots, in glasshouses. 50 Sorghum halepense chaffy seeds per pot were sown at 1, 5, 10, 15, 20, 25 cm depth. Treatments were used in 4 repeats. Peat:sand mixture in 3:1 ratio was used in the experiments. From the first germination, weeds were counted in every second day for 3 weeks. Finally, we measured the length of sprouts, the fresh root and sprout weight of the weeds, and--after drying--the dry-matter weight as well. The results of the first experiment (carried out in July 2005) showed that 25% of the seeds came up from 15 cm. Most of the weeds (64%) came up from 1 cm depth. Answering to our expectations, the ratio of germination from 5 cm depth was also high: it was 56%. The ratio of germination from 10 cm depth was also good (58%). Another experiment was carried out in August 2005, where the germination of Sorghum halepense was investigated from 20 and 25 cm depth. The results show that in spite of the small size of its seeds (5-7 mm), Johnson grass is able to germinate from 20, 25 cm depth. 30% of the sown seeds germinated from 20 cm depth, and because of the slowing-down of the growth only 6% of them germinated from 25 cm depth.

  4. Dynamic plumbing systems along the 100 km long Arctic Vestnesa Ridge

    NASA Astrophysics Data System (ADS)

    Plaza-Faverola, Andreia; Buenz, Stefan; Vadakkepuliyambatta, Sunil; Mienert, Jurgen; Chand, Shyam; Johnson, Joel; Greinert, Jens

    2014-05-01

    Vestnesa is a ridge-like contour-current controlled sediment succession that lies above young oceanic crust created during the tectonic opening of Fram Strait. It is surrounded by the Molloy transform fault to the southwest, the Molloy deep to the north-west, the Knipovich oceanic ridge to the south-east, and the continental margin of Svalbard to the northeast. Although interrupted in places, a mostly continuous bottom simulating reflector (BSR), the seismic indicator for the base of the gas hydrate stability zone (GHSZ), extends for tens of kilometers from the crest of the ridge towards its northern and southern flanks. High-resolution P-Cable 2D seismic data show vertical fluid migration pathways, distributed in clusters along the 100 km long ridge, connecting the free gas system beneath the GHSZ through a 160-180 m thick hydrate stability zone to seabed pockmarks at the crest of the ridge. Among these clusters only those lying towards the easternmost end of the ridge have been documented to be periodically active in terms of present-day seafloor gas seepage. The methane release activity shows particularly well on 18 kHz echosounder data over a time period from 2008 to 2013. Gas hydrates have been recovered in shallow sediment cores (<6 mbsf) at the active seafloor seepage site. Gas analyses show heavier gases in addition to methane, as a hydrate-forming gas. Within the framework of CAGE - Center for Arctic Gas Hydrate, Environment and Climate, we are investigating the development of the plumbing systems of the Arctic Vestnesa Ridge in space and time domains. We compare the modeled base of the GHSZ for different gas compositions against the depth of the BSR in the region and discuss the elements of fluid migration systems that could explain observed lateral changes in BSR depths and the switching between active and inactive plumbing systems. The Centre of Excellence is funded by the Norwegian Research Council (grant No. 223259) over a period of ten years.

  5. The depth dependence of earthquake duration and implications for rupture mechanisms

    USGS Publications Warehouse

    Vidale, J.E.; Houston, H.

    1993-01-01

    THE duration of rupture is a fundamental characteristic of earthquakes, and is important for understanding the mechanics of faulting1,2. The complexity of the seismic source and the incoherence of the high-frequency seismic wavefield often inhibit the identification, location and timing of features in the later part of earthquake rupture. Here we sum many teleseismic records from regional seismic arrays, producing an unusually clear depiction of the earthquake source at short periods by suppressing background noise and coda generated near the receivers. The ending, as well as the beginning, of rupture is clearly identifiable for most earthquakes examined. Measurements of 130 large earthquakes show that near 100 km depth, rupture duration averages 11s when scaled to a moment of 1026 dyn cm; this decreases to 5.5 s at 650 km depth. Models of faulting suggest that duration should be inversely proportional to the shear-wave velocity and the cube root of stress drop. Thus, to explain the observed twofold decrease in duration with depth, stress drops would have to increase by a factor of four, as shear velocity increases with depth by only about 20%. However, observed stress drops show no strong trend with depth3,4, suggesting that the faulting process changes with depth.

  6. Effect of depth-dependent shear modulus on tsunami generation along subduction zones

    USGS Publications Warehouse

    Geist, E.L.; Bilek, S.L.

    2001-01-01

    Estimates of the initial size of tsunamis generated by subduction zone earthquakes are significantly affected by the choice of shear modulus at shallow depths. Analysis of over 360 circum-Pacific subduction zone earthquakes indicates that for a given seismic moment, source duration increases significantly with decreasing depth (Bilek and Lay, 1998; 1999). Under the assumption that stress drop is constant, the increase of source duration is explained by a 5-fold reduction of shear modulus from depths of 20 km to 5 km. This much lower value of shear modulus at shallow depths in comparison to standard earth models has the effect of increasing the amount of slip estimated from seismic moment determinations, thereby increasing tsunami amplitude. The effect of using depth dependent shear modulus values is tested by modeling the tsunami from the 1992 Nicaraguan tsunami earthquake using a previously determined moment distribution (lhmle??, 1996a). We find that the tide gauge record of this tsunami is well matched by synthetics created using the depth dependent shear modulus and moment distribution. Because excitation of seismic waves also depends on elastic heterogeneity, it is important, particularly for the inversion of short period waves, that a consistent seismic/tsunami shear modulus model be used for calculating slip distributions.

  7. Down-depth Seismicity Gaps and the Shape of the Seismic Zone along the entire Indonesian arc from Relocated Hypocenters

    NASA Astrophysics Data System (ADS)

    Das, S.

    2005-05-01

    Using thousands of handpicked P, S, pP, sP, PcP, and ScP phases from digitally recorded seismograms, together with International Seismological Centre reported phases, we obtain improved hypocentral locations for ~2600 earthquakes deeper than 50 km with mb > ~5.0 earthquakes, for the period 1962 to September 1996, along the Indonesian subduction zone. The seismicity distribution is found to be very non-uniform both along the arc and in depth. Gaps in the relocated hypocenters exist along depth in most places of the arc, with its upper edge varying from 100-450 km depth and its lower edge from 350-670 km in different portions of the arc. The relocated hypocenters show that (1) a portion of the Indonesian arc between ~110°E and 123°E longitude, and deeper than ~500 km, is dipping southward at an angle of ~75°, that is, in a direction opposite to the upper part of the north dipping slab, suggesting southward lateral flow in the mantle, relative to the plate motion vector here. (2) East of about 108°E, the seismic zone is wider near 670 km than near the 500 km depth. (3) The seismic zone between 129--131°E in the 100--200 km depth range is the widest along the arc both in strike and downdip. This region, near the highest arc curvature, has the highest seismic activity, and is the only part of the arc with earthquakes continuously occurring from the surface down to below 600 km. (4) The very deep earthquakes under Sulawesi are shown to be part of the west-southwest dipping Seram slab. (5) In the westernmost part of the Banda arc, the slab is under downdip tension in the 50-250 km depth range, while the deepest portion of the slab in this region is under compression. From 128-131°E the slab between 100--200 km depth is under mainly horizontal compression. Our study supports the "two-slab" model for the Banda arc. 3-D computer animations of the subduction zone will be presented. Das, S. (2004) Seismicity Gaps and the Shape of the Seismic Zone in the Banda Sea Region

  8. Underwater acoustic positioning system for the SMO and KM3NeT - Italia projects

    SciTech Connect

    Viola, S.; Barbagallo, G.; Cacopardo, G.; Calí, C.; Cocimano, R.; Coniglione, R.; Costa, M.; Cuttone, G.; D'Amato, C.; D'Amato, V.; D'Amico, A.; De Luca, V.; Del Tevere, F.; Distefano, C.; Ferrera, F.; Gmerk, A.; Grasso, R.; Imbesi, M.; Larosa, G.; Lattuada, D.; and others

    2014-11-18

    In the underwater neutrino telescopes, the positions of the Cherenkov light sensors and their movements must be known with an accuracy of few tens of centimetres. In this work, the activities of the SMO and KM3NeT-Italia teams for the development of an acoustic positioning system for KM3NeT-Italia project are presented. The KM3NeT-Italia project foresees the construction, within two years, of 8 towers in the view of the several km{sup 3}-scale neutrino telescope KM3NeT.

  9. Mechanisms and depths of atlantic transform earthquakes

    NASA Technical Reports Server (NTRS)

    Engeln, J. F.; Wiens, D. A.; Stein, S.

    1986-01-01

    Mechanisms and depths of 40 earthquakes on major transforms along the Mid-Atlantic Ridge are studied in order to identify events that deviate from the transform-parallel strike-slip motion. Long and short period waves and Rayleigh wave spectral amplitudes are used to analyze focal mechanisms, depths, source time functions, and seismic moments of earthquakes. The relationship between centroid depths and transform thermal structures is examined. The data reveal that transform earthquake centroid depths occur above the predicted 400 C isotherms and the oceanic intraplate depths extend to the 750 C isotherm. Slip rates inferred from seismic moment releases are compared to those predicted by plate motions and good correlation is detected. The difference in the centroid depths of transform and interplate seismicity indicates transforms are either weaker or higher temperatures than expected.

  10. Learning the missing values in depth maps

    NASA Astrophysics Data System (ADS)

    Yin, Xuanwu; Wang, Guijin; Zhang, Chun; Liao, Qingmin

    2013-12-01

    In this paper, we consider the task of hole filling in depth maps, with the help of an associated color image. We take a supervised learning approach to solve this problem. The model is learnt from the training set, which contain pixels that have depth values. Then we apply supervised learning to predict the depth values in the holes. Our model uses a regional Markov Random Field (MRF) that incorporates multiscale absolute and relative features (computed from the color image), and models depths not only at individual points but also between adjacent points. The experiments show that the proposed approach is able to recover fairly accurate depth values and achieve a high quality depth map.

  11. Evidence for Methyl-Compound-Activated Life in Coal Bed System 2 km Below Sea Floor

    NASA Astrophysics Data System (ADS)

    Trembath-reichert, E.; Morono, Y.; Dawson, K.; Wanger, G.; Bowles, M.; Heuer, V.; Hinrichs, K. U.; Inagaki, F.; Orphan, V. J.

    2014-12-01

    IODP Expedition 337 set the record for deepest marine scientific drilling down to 2.4 kmbsf. This cruise also had the unique opportunity to retrieve deep cores from the Shimokita coal bed system in Japan with the aseptic and anaerobic conditions necessary to look for deep life. Onboard scientists prepared nearly 1,700 microbiology samples shared among five different countries to study life in the deep biosphere. Samples spanned over 1 km in sampling depths and include representatives of shale, sandstone, and coal lithologies. Findings from previous IODP and deep mine expeditions suggest the genetic potential for methylotrophy in the deep subsurface, but it has yet to be observed in incubations. A subset of Expedition 337 anoxic incubations were prepared with a range of 13C-methyl substrates (methane, methylamine, and methanol) and maintained near in situ temperatures. To observe 13C methyl compound metabolism over time, we monitored the δ13C of the dissolved inorganic carbon (by-product of methyl compound metabolism) over a period of 1.5 years. Elemental analysis (EA), ion chromatograph (IC), 13C volatile fatty acid (VFA), and mineral-associated microscopy data were also collected to constrain initial and endpoint conditions in these incubations. Our geochemical evidence suggests that the coal horizon incubated with 13C-methane showed the highest activity of all methyl incubations. This provides the first known observation of methane-activated metabolism in the deep biosphere, and suggests there are not only active cells in the deeply buried terrigenous coal bed at Shimokita, but the presence of a microbial community activated by methylotrophic compounds.

  12. The 130-km-long Green Valley Fault Zone of Northern California: Discontinuities Regulate Its Earthquake Recurrence

    NASA Astrophysics Data System (ADS)

    Lienkaemper, J. J.

    2012-12-01

    comparable to the 6 mm/yr Holocene slip rate observed on the NCF (Kelson et al., 1996). Microearthquakes on the GVF reach a depth of ~14 km. Using methods of Savage and Lisowski (1993) for the GVF suggests that creep may on average extend to depths of ~7.5 km, leaving a width of ~6.5 km of locked fault zone below. Trenching on the SGVF indicates 400 (±50) years have elapsed since the most recent large earthquake (MRE) in 1610±50 yr CE. Previous earthquake recurrence intervals (RI) in the past millennium indicate a mean RI of 200±80 yr (μ±σ) for the SGVF, which is much shorter than the 400-yr open interval. Preliminary evidence from trenching on the BF gives a MRE of 1630±100 yr CE, which may thus coincide with of the MRE on the SGVF. If the MRE on the BF and SGVF sections is the same earthquake, then its expected larger size (M~6.9-7.0 vs 6.7) and greater fault complexity may have produced a large stress drop, which would possibly help explain the current long open interval. The SGVF paleoseismic recurrence model is consistent with a simple probabilistic rupture model (i.e., 50%-probable rupture across 1-4 km steps) and with a Brownian Passage Time recurrence model with a mean RI of 250 yr, CV (coefficient of variation, σ/μ) of 0.6, and a 30-yr rupture probability of 20-25%.

  13. Moho Depth Variation Beneath Southwest Japan Revealed From Inverted Velocity Structure Based on Receiver Functions

    NASA Astrophysics Data System (ADS)

    Shiomi, K.; Obara, K.; Sato, H.

    2004-12-01

    We determine the depth variation of the Moho discontinuity beneath Chugoku-Shikoku region, southwest Japan. We apply the receiver function analysis to teleseismic waveforms from more than 250 earthquakes with magnitude 5.5 or larger recorded by the High Sensitivity Seismograph Network (Hi-net). Integrating estimated receiver functions into six groups according to the back azimuth of each station, we estimate the seismic velocity structure for every group of the receiver functions by using the improved linearized time-domain waveform inversion method. This improved method adopts a weighting function to determine the shallow structure well and estimate both S and P wave velocity, simultaneously. We detect a clear velocity discontinuity corresponding to the Moho across which the S wave velocity changes to 4.5 km/s from 3.7 km/s. The depth of the discontinuity is about 30 km beneath northern (the Japan Sea) and southern (the Pacific) coastlines and more than 40 km beneath central part of the study region. In the central part, a low velocity layer (LVL) with 10 km thickness exists under the Moho. The depth of the upper boundary of the LVL is 45 to 50 km. The Philippine Sea plate (PHS) is subducting toward the northwest from the Nankai Trough beneath the Chugoku-Shikoku region where both the continental and the oceanic Moho exist. The LVL corresponds to the subducting oceanic crust of the PHS and the oceanic Moho is the bottom of the oceanic crust. The continental Moho of the Eurasian plate lies above the low velocity oceanic crust. However, at stations in the northern and southern part of the study region, we find only one major velocity discontinuity. We read the depth of these clear discontinuities from the inverted velocity models and map the Moho depth at the conversion point. By interpolating the results, we separately draw the depth contour of the continental and the oceanic Moho beneath Chugoku-Shikoku region under the assumptions: (1) the Moho of the Pacific

  14. Gravity and geoid anomalies of the Philippine Sea: Evidence on the depth of compensation for the negative residual water depth anomaly

    NASA Technical Reports Server (NTRS)

    Bowin, C.

    1982-01-01

    A negative free-air gravity anomaly which occurs in the central part of the Philippine Sea was examined to determine the distribution and nature of possible regional mass excesses or deficiencies. Geoid anomalies from GEOS-3 observation were positive. A negative residual geoid anomaly consistent with the area of negative free-air gravity anomalies were found. Theoretical gravity-topography and geoid-topography admittance functions indicated that high density mantle at about 60 km dept could account for the magnitudes of the gravity and residual geoid anomaly and the 1 km residual water depth anomaly in the Philippine Sea. The negative residual depth anomaly may be compensated for by excess density in the uppermost mantle, but the residual geoid and regional free-air gravity anomalies and a slow surface wave velocity structure might result from low-density warm upper mantle material lying beneath the zone of high-density uppermost mantle. From a horizontal disk approximation, the depth of the low-density warm mantle was estimated to be on the order of 200 km.

  15. Upper-crustal velocity structure along 150 km of the Mendeleev Ridge from tomographic inversion of long-offset refraction data collected during HLY0602

    NASA Astrophysics Data System (ADS)

    Vermeesch, P. M.; van Avendonk, H. J.; Lawver, L. A.

    2007-12-01

    In the summer of 2006 we acquired a unique seismic refraction data set on the Chukchi Borderlands and Mendeleev Ridge utilizing USCGC Healy and two helicopters. The array on the Mendeleev Ridge consisted of 14 instrument sites with 12 km spacing between instruments. On every site we deployed a Sea-Ice Seismometer (S- IS) especially designed for this experiment in the ice-covered part of the Arctic Ocean. Each S-IS contained a vertical component geophone that was buried in the ice and a hydrophone that was hanging from the ice edge in the water. From the 14 instrument sites, 10 contained useful data with refracted crustal arrivals up to offsets of 40 km. Because of extensive drifting of the receivers (40 km in 5 days and containing numerous loops), and because of the irregular geometry of airgun shots due to the problems of sailing through ice-covered seas, a 3D ray-shooting code was developed to calculate ray paths within a 3D velocity model that extends along 150 km in the X- direction and along 35 km in the Y-direction. Using the velocity model proposed by Lebedeva-Ivanova et al. (2006) we observe that the maximum depth of our calculated ray paths is 11 km below sealevel. Using all the available data, the Root Mean Square (RMS) difference between observed and calculated travel-times is of the order of 500 ms. Initially a simple 1D travel-time inversion was developed to constrain the velocity structure of the basement underneath a layer of water (3D) and a layer of sediment (1D). This inversion was carried out on 2 pairs of receivers: one pair in the NNE and one more towards the SSW part of the line. Inversion of S-IS 45N-42 (NNE) results in a model with a velocity of 5.5 km s-1 at the top of the basement, slowly increasing to a velocity of 5.7 km s-1 at 3 km below the top of the basement (RMS = 117 ms). Inversion of S-IS 49-45S (SSW) results in a model with a velocity of 4.8 km s-1 at the top of the basement, increasing to a velocity of 5.9 km s-1 at 3 km below

  16. Are face representations depth cue invariant?

    PubMed

    Dehmoobadsharifabadi, Armita; Farivar, Reza

    2016-06-01

    The visual system can process three-dimensional depth cues defining surfaces of objects, but it is unclear whether such information contributes to complex object recognition, including face recognition. The processing of different depth cues involves both dorsal and ventral visual pathways. We investigated whether facial surfaces defined by individual depth cues resulted in meaningful face representations-representations that maintain the relationship between the population of faces as defined in a multidimensional face space. We measured face identity aftereffects for facial surfaces defined by individual depth cues (Experiments 1 and 2) and tested whether the aftereffect transfers across depth cues (Experiments 3 and 4). Facial surfaces and their morphs to the average face were defined purely by one of shading, texture, motion, or binocular disparity. We obtained identification thresholds for matched (matched identity between adapting and test stimuli), non-matched (non-matched identity between adapting and test stimuli), and no-adaptation (showing only the test stimuli) conditions for each cue and across different depth cues. We found robust face identity aftereffect in both experiments. Our results suggest that depth cues do contribute to forming meaningful face representations that are depth cue invariant. Depth cue invariance would require integration of information across different areas and different pathways for object recognition, and this in turn has important implications for cortical models of visual object recognition. PMID:27271993

  17. Pictorial depth probed through relative sizes

    PubMed Central

    Wagemans, Johan; van Doorn, Andrea J; Koenderink, Jan J

    2011-01-01

    In the physical environment familiar size is an effective depth cue because the distance from the eye to an object equals the ratio of its physical size to its angular extent in the visual field. Such simple geometrical relations do not apply to pictorial space, since the eye itself is not in pictorial space, and consequently the notion “distance from the eye” is meaningless. Nevertheless, relative size in the picture plane is often used by visual artists to suggest depth differences. The depth domain has no natural origin, nor a natural unit; thus only ratios of depth differences could have an invariant significance. We investigate whether the pictorial relative size cue yields coherent depth structures in pictorial spaces. Specifically, we measure the depth differences for all pairs of points in a 20-point configuration in pictorial space, and we account for these observations through 19 independent parameters (the depths of the points modulo an arbitrary offset), with no meaningful residuals. We discuss a simple formal framework that allows one to handle individual differences. We also compare the depth scale obtained by way of this method with depth scales obtained in totally different ways, finding generally good agreement. PMID:23145258

  18. Clutter depth discrimination using the wavenumber spectrum.

    PubMed

    Benjamin Reeder, D

    2014-01-01

    Clutter depth is a key parameter in mid-frequency active sonar systems to discriminate between sources of clutter and targets of interest. A method is needed to remotely discriminate clutter depth by information contained in the backscattered signal-without a priori knowledge of that depth. Presented here is an efficient approach for clutter depth estimation using the structure in the wavenumber spectrum. Based on numerical simulations for a simple test case in a shallow water waveguide, this technique demonstrates the potential capability to discriminate between a clutter source in the water column vs one on the seabed.

  19. Depth Perception In Remote Stereoscopic Viewing Systems

    NASA Technical Reports Server (NTRS)

    Diner, Daniel B.; Von Sydow, Marika

    1989-01-01

    Report describes theoretical and experimental studies of perception of depth by human operators through stereoscopic video systems. Purpose of such studies to optimize dual-camera configurations used to view workspaces of remote manipulators at distances of 1 to 3 m from cameras. According to analysis, static stereoscopic depth distortion decreased, without decreasing stereoscopitc depth resolution, by increasing camera-to-object and intercamera distances and camera focal length. Further predicts dynamic stereoscopic depth distortion reduced by rotating cameras around center of circle passing through point of convergence of viewing axes and first nodal points of two camera lenses.

  20. Incipient speciation across a depth gradient in a scleractinian coral?

    PubMed

    Carlon, David B; Budd, Ann F

    2002-11-01

    A few marine cases have demonstrated morphological and genetic divergence in the absence of spatial barriers to gene flow, suggesting that the initial phase of speciation is possible without geographic isolation. In the Bocas del Toro Archipelago of the Atlantic Coast of Panama, we found two morphotypes of the scleractinian coral Favia fragum with opposing depth distributions. One morphotype fit the classical description of F. fragum and was most abundant at 3 m depth. A second morphotype was distinguished by raised corallites and was restricted to < or = 1 m depth. The two morphotypes overlapped in distribution at 1 m depth. Multivariate analysis of polyp-level characters (shape and distribution of septa within corallites) divided samples into two groups corresponding to initial qualitative observations of colony shape and corallite relief. To determine whether reduced gene flow maintains morphological variation, we measured the frequencies of alleles at five allozyme loci in both morphotypes at three sites 1-2 km distant. While there were significant differences in allele frequencies between morphotypes within sites, there were also frequency differences among sites at most loci, with the exception of nearly fixed alleles at the PGM locus. Extremely low heterozygosity permitted us to use haplotypes to compare genetic distance between morphotypes and among sites. Comparisons between haplotype data and a null model assuming gene flow between morphotypes showed that the two morphotypes shared significantly fewer haplotypes than expected, and average genetic distance between morphotypes was significantly greater than expected. Partitioning haplotype variation with analysis of molecular variance demonstrated that 35% of the variation was explained by morphotype, whereas 28% of the variation was explained by site. Two PGM heterozygotes and several individuals homozygous for rare PGM alleles are consistent with hybridization, and perhaps introgression by selfing within

  1. An Exploration of the Needling Depth in Acupuncture: The Safe Needling Depth and the Needling Depth of Clinical Efficacy

    PubMed Central

    Lin, Jaung-Geng; Chou, Pei-Chi; Chu, Heng-Yi

    2013-01-01

    Objective. To explore the existing scientific information regarding safe needling depth of acupuncture points and the needling depth of clinical efficacy. Methods. We searched the PubMed, EMBASE, Cochrane, Allied and Complementary Medicine (AMED), The National Center for Complementary and Alternative Medicine (NCCAM), and China National Knowledge Infrastructure (CNKI) databases to identify relevant monographs and related references from 1991 to 2013. Chinese journals and theses/dissertations were hand searched. Results. 47 studies were recruited and divided into 6 groups by measuring tools, that is, MRI, in vivo evaluation, CT, ultrasound, dissected specimen of cadavers, and another group with clinical efficacy. Each research was analyzed for study design, definition of safe depth, and factors that would affect the measured depths. Depths of clinical efficacy were discussed from the perspective of de-qi and other clinical observations. Conclusions. Great inconsistency in depth of each point measured from different subject groups and tools exists. The definition of safe depth should be established through standardization. There is also lack of researches to compare the clinical efficacy. A well-designed clinical trial selecting proper measuring tools to decide the actual and advisable needling depth for each point, to avoid adverse effects or complications and promote optimal clinical efficacy, is a top priority. PMID:23935678

  2. Lateral detachment in progress within the Vrancea slab (Romania): inferences from intermediate-depth seismicity patterns

    NASA Astrophysics Data System (ADS)

    Mitrofan, Horia; Anghelache, Mirela-Adriana; Chitea, Florina; Damian, Alexandru; Cadicheanu, Nicoleta; Vişan, Mădălina

    2016-05-01

    Within a slab experiencing present-day lateral break-off, a particular type of earthquakes is expected to cluster at the detachment horizon tip: namely, events generated by reverse faulting, with the approximately horizontal compression involved acting along the strike of the slab. Such a cluster of moderate magnitude earthquakes (4.7 ≤ mb ≤ 5.0) was identified in this study at the 160-175 km depth range of the Vrancea seismogenic body, in the Southeast Carpathians mountains collision environment. The corresponding cluster epicentres were systematically positioned at the boundary between a region being subject (cf. published GPS records), to present-day upward movements, and another one that underwent present-day subsidence. Such an overall setting seems to suggest that a lateral break-off is currently developing at the indicated depth within the Vrancea slab, leading to topographic uplift above the already detached slab section, and to enhanced subsidence above the section to which the gravitational slab pull was being transferred. In addition, by taking into account some systematic time correspondence which we documented between moderate magnitude events of the 160-175 km depth cluster and the subsequent strong Vrancea shocks (Mw ≥ 6.9), it appears that the latter, although occurring at much shallower depths (roughly, in the 80-140 km range), were also controlled by the break-off progress.

  3. Increased depth-diameter ratios in the Medusae Fossae Formation deposits of Mars

    NASA Technical Reports Server (NTRS)

    Barlow, N. G.

    1993-01-01

    Depth to diameter ratios for fresh impact craters on Mars are commonly cited as approximately 0.2 for simple craters and 0.1 for complex craters. Recent computation of depth-diameter ratios in the Amazonis-Memnonia region of Mars indicates that craters within the Medusae Fossae Formation deposits found in this region display greater depth-diameter ratios than expected for both simple and complex craters. Photoclinometric and shadow length techniques have been used to obtain depths of craters within the Amazonis-Memnonia region. The 37 craters in the 2 to 29 km diameter range and displaying fresh impact morphologies were identified in the area of study. This region includes the Amazonian aged upper and middle members of the Medusae Fossae Formation and Noachian aged cratered and hilly units. The Medusae Fossae Formation is characterized by extensive, flat to gently undulating deposits of controversial origin. These deposits appear to vary from friable to indurated. Early analysis of crater degradation in the Medusae Fossae region suggested that simple craters excavated to greater depths than expected based on the general depth-diameter relationships derived for Mars. However, too few craters were available in the initial analysis to estimate the actual depth-diameter ratios within this region. Although the analysis is continuing, we are now beginning to see a convergence towards specific values for the depth-diameter ratio depending on geologic unit.

  4. Snow Depth Mapping at a Basin-Wide Scale in the Western Arctic Using UAS Technology

    NASA Astrophysics Data System (ADS)

    de Jong, T.; Marsh, P.; Mann, P.; Walker, B.

    2015-12-01

    Assessing snow depths across the Arctic has proven to be extremely difficult due to the variability of snow depths at scales from metres to 100's of metres. New Unmanned Aerial Systems (UAS) technology provides the possibility to obtain centimeter level resolution imagery (~3cm), and to create Digital Surface Models (DSM) based on the Structure from Motion method. However, there is an ongoing need to quantify the accuracy of this method over different terrain and vegetation types across the Arctic. In this study, we used a small UAS equipped with a high resolution RGB camera to create DSMs over a 1 km2 watershed in the western Canadian Arctic during snow (end of winter) and snow-free periods. To improve the image georeferencing, 15 Ground Control Points were marked across the watershed and incorporated into the DSM processing. The summer DSM was subtracted from the snowcovered DSM to deliver snow depth measurements across the entire watershed. These snow depth measurements were validated by over 2000 snow depth measurements. This technique has the potential to improve larger scale snow depth mapping across watersheds by providing snow depth measurements at a ~3 cm . The ability of mapping both shallow snow (less than 75cm) covering much of the basin and snow patches (up to 5 m in depth) that cover less than 10% of the basin, but contain a significant portion of total basin snowcover, is important for both water resource applications, as well as for testing snow models.

  5. Chromophore-modified antitumor anthracenediones: synthesis, DNA binding, and cytotoxic activity of 1,4-bis[(aminoalkyl)amino]benzo[g]-phthalazine-5,10-diones.

    PubMed

    Gandolfi, C A; Beggiolin, G; Menta, E; Palumbo, M; Sissi, C; Spinelli, S; Johnson, F

    1995-02-01

    As part of a program aimed at exploring the effect of the introduction of heteroatoms into the anthracene-9,10-dione chromophore, we have synthesized novel 1,4-bis[(aminoalkyl)amino]-benzo[g]phthalazine-5,10-diones (BPDs) 1 which are related to the antitumor agents ametantrone and mitoxantrone. Derivatives 1 were prepared by chromic acid oxidation of acylated benzo[g]phthalazines 5 followed by acid hydrolysis or by silylation-amination of 5,10-dihydroxybenzo[g]phthalazine-1,4-dione (8). The 1-[(aminoalkyl)amino]-4-amino congeners 2 were isolated in low yields as byproducts from the oxidation of 5. Against a panel of human tumor cell lines, the benzo[g]phthalazine-5,10-diones 1 and 2 exhibited cytotoxic activity comparable or even superior to that of mitoxantrone. In compounds 1, structure-activity relationships different than those operative in the carbocyclic series appeared to emerge. DNA-binding studies with the ametantrone-like compound 1c and its single-armed congener 2c indicated that the introduction of a 2,3-diaza subunit into the anthracene-9,10-dione chromophore reduces the affinity of the drug for DNA in comparison with ametantrone. On the other hand, the number of side-chain groups does not affect binding to a great extent. These findings seem to suggest mechanisms of cell death other than those induced by simple interaction of the 1,4-BPDs 1 and 2 with DNA.

  6. Influence of meteorological conditions on PM 2.5 and PM 2.5-10 concentrations during the monsoon season in Hanoi, Vietnam

    NASA Astrophysics Data System (ADS)

    Hien, P. D.; Bac, V. T.; Tham, H. C.; Nhan, D. D.; Vinh, L. D.

    Twenty-four hour samples of air particulate matter with aerodynamic diameters from 2 to 10 μm (PM 10) and <2.5 μm (PM 2.5) were collected in Hanoi throughout 1 year since August 1998. The air sampler was located in a meteorological garden where routine surface observations and upper air radiosoundings were conducted. Very high PM 2.5 and PM 2.5-10 concentrations were observed in conjunction with the occurrence of nocturnal radiation inversions from October to December and subsidence temperature inversions (STI) from January to March. In the first case, the PM 2.5-10 fraction was much enhanced and particulate pollution was significantly higher at night than in daytime. During the occurence of STIs particulate mass was almost evenly distributed among the two fractions and no significant diurnal variations in concentrations were observed. In summer (May-September) particulate pollution was much lower than in winter. The multiple regression of 24-h particulate concentrations against meteorological parameters for both the winter and summer monsoon periods shows that the most important determinants of PM 2.5 are wind speed and air temperature, while rainfall and relative humidity largely control the daily variations of PM 2.5-10, indicating the high abundance of soil dust in this fraction. As to turbulence parameters, among the determinants of 24-h particulate concentrations are the vertical gradients of potential temperature and wind speed recorded at 06.30 and 18.30, respectively. Meteorological parameters could explain from 60% to 74% of the day-to-day variations of particulate concentrations.

  7. Curie Point Depth Estimates Beneath the Incipient Okavango Rift Zone, Northwest Botswana

    NASA Astrophysics Data System (ADS)

    Leseane, K.; Atekwana, E. A.; Mickus, K. L.; Mohamed, A.; Atekwana, E. A.

    2013-12-01

    We investigated the regional thermal structure of the crust beneath the Okavango Rift Zone (ORZ), surrounding cratons and orogenic mobile belts using the Curie Point Depth (CPD) estimates. Estimating the depth to the base of magnetic sources is important in understanding and constraining the thermal structure of the crust in zones of incipient continental rifting where no other data are available to image the crustal thermal structure. Our objective was to determine if there are any thermal perturbations within the lithosphere during rift initiation. The top and bottom of the magnetized crust were calculated using the two dimensional (2D) power-density spectra analysis and three dimensional (3D) inversions of the total field magnetic data of Botswana in overlapping square windows of 1degree x 1 degree. The calculated CPD estimates varied between ~8 km and ~24 km. The deepest CPD values (16-24 km) occur under the surrounding cratons and orogenic mobile belts whereas the shallowest CPD values were found within the ORZ. CPD values of 8 to 10 km occur in the northeastern part of ORZ; a site of more developed rift structures and where hot springs are known to occur. CPD values of 12 to 16 km were obtained in the southwestern part of the ORZ where rift structures are progressively less developed and where the rift terminates. The results suggests possible thermal anomaly beneath the incipient ORZ. Further geophysical studies as part of the PRIDE (Project for Rift Initiation Development and Evolution) project are needed to confirm this proposition.

  8. Effects of training and anthropometric factors on marathon and 100 km ultramarathon race performance

    PubMed Central

    Tanda, Giovanni; Knechtle, Beat

    2015-01-01

    Background Marathon (42 km) and 100 km ultramarathon races are increasing in popularity. The aim of the present study was to investigate the potential associations of anthropometric and training variables with performance in these long-distance running competitions. Methods Training and anthropometric data from a large cohort of marathoners and 100 km ultramarathoners provided the basis of this work. Correlations between training and anthropometric indices of subjects and race performance were assessed using bivariate and multiple regression analyses. Results A combination of volume and intensity in training was found to be suitable for prediction of marathon and 100 km ultramarathon race pace. The relative role played by these two variables was different, in that training volume was more important than training pace for the prediction of 100 km ultramarathon performance, while the opposite was found for marathon performance. Anthropometric characteristics in terms of body fat percentage negatively affected 42 km and 100 km race performance. However, when this factor was relatively low (ie, less than 15% body fat), the performance of 42 km and 100 km races could be predicted solely on the basis of training indices. Conclusion Mean weekly training distance run and mean training pace were key predictor variables for both marathon and 100 km ultramarathon race performance. Predictive correlations for race performance are provided for runners with a relatively low body fat percentage. PMID:25995653

  9. Neutrophil activation induced by the lectin KM+ involves binding to CXCR2.

    PubMed

    Pereira-da-Silva, Gabriela; Moreno, Andréa N; Marques, Fabiana; Oliver, Constance; Jamur, Maria Célia; Panunto-Castelo, Ademilson; Roque-Barreira, Maria Cristina

    2006-01-01

    The lectin KM+ from Artocarpus integrifolia, also known as artocarpin, induces neutrophil migration by haptotaxis. The interactions of KM+ with both neutrophils and the extracellular matrix depend on the lectin's ability to recognize mannose-containing glycans. In the present study, we characterized the binding of KM+ to human neutrophils and the responses stimulated by this binding. Exposure to KM+ results in cell polarization, formation of a lamellipodium, and induction of deep ruffles on the cell surface. By fluorescence microscopy, we observed that KM+ is distributed homogeneously over the cell surface. KM+/ligand complexes are rapidly internalized, reaching maximum intracellular concentrations at 120 min, and decreasing thereafter. Furthermore, KM+ binding to the surface of human neutrophils is inhibited by the specific sugars, d-mannose or mannotriose. KM+-induced neutrophil migration is inhibited by pertussis toxin as well as by inhibition of CXCR2 activity. These results suggest that the KM+ ligand on the neutrophil surface is a G protein-coupled receptor (GPCR). The results also suggest that neutrophil migration induced by KM+ involves binding to CXCR2.

  10. A quantile count model of water depth constraints on Cape Sable seaside sparrows

    USGS Publications Warehouse

    Cade, B.S.; Dong, Q.

    2008-01-01

    1. A quantile regression model for counts of breeding Cape Sable seaside sparrows Ammodramus maritimus mirabilis (L.) as a function of water depth and previous year abundance was developed based on extensive surveys, 1992-2005, in the Florida Everglades. The quantile count model extends linear quantile regression methods to discrete response variables, providing a flexible alternative to discrete parametric distributional models, e.g. Poisson, negative binomial and their zero-inflated counterparts. 2. Estimates from our multiplicative model demonstrated that negative effects of increasing water depth in breeding habitat on sparrow numbers were dependent on recent occupation history. Upper 10th percentiles of counts (one to three sparrows) decreased with increasing water depth from 0 to 30 cm when sites were not occupied in previous years. However, upper 40th percentiles of counts (one to six sparrows) decreased with increasing water depth for sites occupied in previous years. 3. Greatest decreases (-50% to -83%) in upper quantiles of sparrow counts occurred as water depths increased from 0 to 15 cm when previous year counts were 1, but a small proportion of sites (5-10%) held at least one sparrow even as water depths increased to 20 or 30 cm. 4. A zero-inflated Poisson regression model provided estimates of conditional means that also decreased with increasing water depth but rates of change were lower and decreased with increasing previous year counts compared to the quantile count model. Quantiles computed for the zero-inflated Poisson model enhanced interpretation of this model but had greater lack-of-fit for water depths > 0 cm and previous year counts 1, conditions where the negative effect of water depths were readily apparent and fitted better with the quantile count model.

  11. The depths of the mare basalt source region

    NASA Technical Reports Server (NTRS)

    Binder, A. B.

    1985-01-01

    Chemical data for the parental magmas of the nine known VLT Array I pyroclastic glasses show statistically significant trends due to olivine (approximately Fo83) control during their formation by partial melting. The compositional scatter is largely due to compositional variations in the source regions on the + or - 1 percent level. This compositional scatter is small when one considers that the scale of the source region is up to 1000 km, but is sufficient to make positive identification of the residual phase(s) in the source regions difficult. Nevertheless, when the effects of the scatter are properly modeled, it is relatively clear that olivine is the residual phase in the source region. Hence these data and additional constraints indicate that the source regions are at shallow depths in the moon.

  12. Effect of acupuncture depth on muscle pain

    PubMed Central

    2011-01-01

    Background While evidence supports efficacy of acupuncture and/or dry needling in treating musculoskeletal pain, it is unclear which needling method is most effective. This study aims to determine the effects of depth of needle penetration on muscle pain. Methods A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle), muscle group (depth of 10 mm: the extensor digital muscle) and non-segmental group (depth of 10 mm: the anterior tibial muscle). Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise. Results Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle) and muscle group (depth of 10 mm: the extensor digital muscle) were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle) was a significantly higher than control group; however, there was no significant difference between the control and other groups. Conclusion The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain. PMID:21696603

  13. "Depth" Matters in High School Science Studies

    ERIC Educational Resources Information Center

    Cavanagh, Sean

    2009-01-01

    This article reports on the findings of a recent study that examines one of the most enduring debates in science instruction--whether "depth" or "breadth" of knowledge is most important. Its authors come down on the side of depth. The study found that high school students who focus more intensely on core topics within their biology, chemistry, and…

  14. Contextualizing Range and Depth in Indian English.

    ERIC Educational Resources Information Center

    D'Souza, Jean

    2001-01-01

    Examines the range and depth of English in India and argues that these Kachruvian notions go a long way towards explaining how the language is used, exploited, extended, and recreated in the sub-continent. Data, both written and spoken, are presented, and it is suggested that in-depth analyses of such data are a prerequisite to any real…

  15. Differential Cognitive Cues in Pictorial Depth Perception.

    ERIC Educational Resources Information Center

    Omari, Issa M.; Cook, Harold

    The experiment described in this report investigates the effects of various cognitive cues in questions asked regarding the relationship of elements in pictorial depth perception. The subjects of this study are 40 third grade Black and Puerto Rican children. They are confronted with four pictures from the Hudson Depth Perception Tests and asked to…

  16. Correlated patterns in hydrothermal plume distribution and apparent magmatic budget along 2500 km of the Southeast Indian Ridge

    USGS Publications Warehouse

    Baker, Edward; Christophe Hémond,; Anne Briais,; Marcia Maia,; Scheirer, Daniel S.; Sharon L. Walker,; Tingting Wang,; Yongshun John Chen,

    2014-01-01

    Multiple geological processes affect the distribution of hydrothermal venting along a mid-ocean ridge. Deciphering the role of a specific process is often frustrated by simultaneous changes in other influences. Here we take advantage of the almost constant spreading rate (65–71 mm/yr) along 2500 km of the Southeast Indian Ridge (SEIR) between 77°E and 99°E to examine the spatial density of hydrothermal venting relative to regional and segment-scale changes in the apparent magmatic budget. We use 227 vertical profiles of light backscatter and (on 41 profiles) oxidation-reduction potential along 27 first and second-order ridge segments on and adjacent to the Amsterdam-St. Paul (ASP) Plateau to map ph, the fraction of casts detecting a plume. At the regional scale, venting on the five segments crossing the magma-thickened hot spot plateau is almost entirely suppressed (ph = 0.02). Conversely, the combined ph (0.34) from all other segments follows the global trend of ph versus spreading rate. Off the ASP Plateau, multisegment trends in ph track trends in the regional axial depth, high where regional depth increases and low where it decreases. At the individual segment scale, a robust correlation between ph and cross-axis inflation for first-order segments shows that different magmatic budgets among first-order segments are expressed as different levels of hydrothermal spatial density. This correlation is absent among second-order segments. Eighty-five percent of the plumes occur in eight clusters totaling ∼350 km. We hypothesize that these clusters are a minimum estimate of the length of axial melt lenses underlying this section of the SEIR.

  17. Correlated patterns in hydrothermal plume distribution and apparent magmatic budget along 2500 km of the Southeast Indian Ridge

    NASA Astrophysics Data System (ADS)

    Baker, Edward T.; Hémond, Christophe; Briais, Anne; Maia, Marcia; Scheirer, Daniel S.; Walker, Sharon L.; Wang, Tingting; Chen, Yongshun John

    2014-08-01

    geological processes affect the distribution of hydrothermal venting along a mid-ocean ridge. Deciphering the role of a specific process is often frustrated by simultaneous changes in other influences. Here we take advantage of the almost constant spreading rate (65-71 mm/yr) along 2500 km of the Southeast Indian Ridge (SEIR) between 77°E and 99°E to examine the spatial density of hydrothermal venting relative to regional and segment-scale changes in the apparent magmatic budget. We use 227 vertical profiles of light backscatter and (on 41 profiles) oxidation-reduction potential along 27 first and second-order ridge segments on and adjacent to the Amsterdam-St. Paul (ASP) Plateau to map ph, the fraction of casts detecting a plume. At the regional scale, venting on the five segments crossing the magma-thickened hot spot plateau is almost entirely suppressed (ph = 0.02). Conversely, the combined ph (0.34) from all other segments follows the global trend of ph versus spreading rate. Off the ASP Plateau, multisegment trends in ph track trends in the regional axial depth, high where regional depth increases and low where it decreases. At the individual segment scale, a robust correlation between ph and cross-axis inflation for first-order segments shows that different magmatic budgets among first-order segments are expressed as different levels of hydrothermal spatial density. This correlation is absent among second-order segments. Eighty-five percent of the plumes occur in eight clusters totaling ˜350 km. We hypothesize that these clusters are a minimum estimate of the length of axial melt lenses underlying this section of the SEIR.

  18. A Moho depth map across the Trans-European Suture Zone from receiver functions

    NASA Astrophysics Data System (ADS)

    Knapmeyer-Endrun, Brigitte; Krüger, Frank

    2013-04-01

    We present a Moho depth map of central-to-eastern Europe based on P-receiver functions from 484 stations. Specifically, the data set includes the roughly 200 stations of the international PASSEQ experiment that were deployed across the Trans-European Suture Zone (TESZ) from eastern Germany to Lithuania from 2006 to 2008. Thus, the data offer the densest coverage for a passive experiment in this area yet. By using additional stations from permanent networks and other temporary deployments, we extend the coverage into Luxembourg, the eastern parts of the Netherlands, Belgium and France to the west, northern Switzerland, Austria and Slovakia to the south, the western parts of Belarus, Ukraine and Russia, and Estonia to the east and Denmark and southern Sweden to the north. In some areas, e.g. across the Polish Basin, strong sediment reverberations complicate the unambiguous identification of the Moho converted Ps-phase and in some cases may completely mask it. The additional use of S-receiver functions, in which direct conversions and multiples are clearly separated, can greatly aid in measuring the Moho Ps-travel time in these cases. Ps-travel times of the Moho conversion vary between 2.5 s and 7.5 s within the region, pointing to strong variations in Moho depth. Depth values were determined by stacking direct conversions and their multiples from P-receiver functions (Zhu & Kanamori, 2000). Special care was taken to use the latest and most detailed information on average crustal P-velocities for the stacking, i.e. values from Majdanski et al. (2012) for Poland, Karousova et al. (2012) for the Czech Republic and from EPcrust (Molinari & Morelli, 2011) for the rest of Europe. The TESZ is imaged as a strong contrast in crustal thickness, from less than 35 km to the west to more than 40 km to the east. This transition seems to be distributed over no more than 30 km laterally. Besides, the character of the Ps-phases converted at the Moho also changes across the TESZ

  19. The Moho depth and the inner crustal structure of the Antarctica region

    NASA Astrophysics Data System (ADS)

    Baranov, Alexey; Morelli, Andrea

    2013-04-01

    Different tectonic units cover the Antarctic territory: platform, orogens and depression structures. This structural variability is reflected both in thickness and physical properties of the crust. This continent has high interest for Earth sciences, because of its origin as the core of the Gondwana supercontinent, and because of a number of present-day peculiar features — such as its being stationary in the global plate tectonic frame, while it is bounded by extensional mid-oceanic ridges, and crossed by the largest known noncollisional mountain range. We present a new Moho map for the Antarctica, derived from geophysical data selected from the literature. The model covers the whole Antarctic region, from the South Pole out to the continental margin, including the Antarctic Peninsula. The Moho depth is represented with a resolution of 1°×1° on a Cartesian grid obtained by an equidistant azimuthal geographical projection. A large volume of new data has been analyzed: mostly seismic experiments, as well as receiver functions and geological studies. In general, we can identify three large domains within the Antarctic continental crust. The oldest Archean and Proterozoic crust of East Antarctica has a thickness of 36-56 km (with an average of about 41 km). The continental crust of the Transantarctic Mountains, the Antarctic Peninsula and Wilkes Basin has a thickness of 30-40 km (with an average Moho of about 30 km). The youngest rifted continental crust of the West Antarctic Rift System has a thickness of 16-28 km (with an average Moho of about 26 km). The mean Moho depth of the whole model is 33.8 km. The new Moho model exhibits some remarkable disagreements at places with respect to global model CRUST 2.0. Difference between these two models in the crustal thickness may amount up to 24 km (rms = 4.2 km) mainly due to improved resolution of our model's Moho boundary. There are significant changes in regions such as the Ross Sea (that may reach -6 / + 12 km

  20. Contour detection combined with depth information

    NASA Astrophysics Data System (ADS)

    Xiao, Jie; Cai, Chao

    2015-12-01

    Many challenging computer vision problems have been proven to benefit from the incorporation of depth information, to name a few, semantic labellings, pose estimations and even contour detection. Different objects have different depths from a single monocular image. The depth information of one object is coherent and the depth information of different objects may vary discontinuously. Meanwhile, there exists a broad non-classical receptive field (NCRF) outside the classical receptive field (CRF). The response of the central neuron is affected not only by the stimulus inside the CRF, but also modulated by the stimulus surrounding it. The contextual modulation is mediated by horizontal connections across the visual cortex. Based on the findings and researches, a biological-inspired contour detection model which combined with depth information is proposed in this paper.

  1. Depth perception through circular movements of dots.

    PubMed

    Ito, Hiroyuki

    2010-01-01

    Elements that move with velocity gradients have been shown to give the impression of depth. In this study, it was found that dots in circular motion around a line of sight give a depth impression corresponding to the gradients of the angular velocities of circular motion on a screen. The results of two experiments show that depth perception through circular motion is as effective as that through expansion or spiral motion, but less effective than that through lateral motion parallax when the local speed distributions on the screen are matched. The present depth effect shows that expansion-contraction, spiral, and circular motions are a continuum in terms of producing depth effects; they differ from lateral motion parallax.

  2. Curie point depth estimation of the Eastern Caribbean

    NASA Astrophysics Data System (ADS)

    Garcia, Andreina; Orihuela Guevara, Nuris

    2013-04-01

    In this paper we present an estimation of the Curie point depth (CPD) on the Eastern Caribbean. The estimation of the CPD was done from satellite magnetic anomalies, by the application of the Centroid method over the studied area. In order to calculate the CPD, the area was subdivided in square windows of side equal to 2°, with an overlap distance of 1° to each other. As result of this research, it was obtained the Curie isotherm grid by using kriging interpolation method. Despite of the oceanic nature of the Eastern Caribbean plate, this map reveals important lateral variations in the interior of the plate and its boundaries. The lateral variations observed in CPD are related with the complexity of thermal processes in the subsurface of the region. From a global perspective, the earth's oceanic provinces show a CPD's smooth behavior, excepting plate boundaries of these oceanic provinces. In this case, the Eastern Caribbean plate's CPD variations are related to both: Plate's boundaries and plate's interior. The maximum CPD variations are observed in the southern boundary of Caribbean plate (9 to 35 km) and over the Lesser Antilles and Barbados prism (16 to 30 km). This behavior reflects the complex geologic evolution history of the studied area, in which has been documented the presence of extensive mantle of basalt and dolerite sills. These sills have been originated in various cycles of cretaceous mantle activity, and have been the main cause of the oceanic crust's thickening in the interior of the Caribbean plate. At the same time, this thickening of the oceanic plate explains the existence of a Mohorovičić discontinuity, with an average depth greater than other regions of the planet, with slight irregularities related to highs of the ocean floor (Nicaragua and Beata Crests, Aves High) but not similar to the magnitude of lateral variations revealed by the Curie isotherm map.

  3. Early lung cancer detection project: Evaluation of 5, 10, 15, 20 tetrakis (4-carboxyphenyl) porphine (H{sub 2}TCPP). Final report

    SciTech Connect

    Tockman, M.S.

    1998-10-01

    The author evaluated a synthetic porphyrin, 5, 10, 15, 20 tetrakis (4-carboxyphenyl) porphene (H{sub 2}TCPP) as a marker of carcinogenesis. H{sub 2}TCPP was compared with two other carcinogenesis markers evaluated in the laboratory for their ability to detect exfoliated sputum cells undergoing transformation to lung cancer. In the present project the authors first established optimal conditions for cultured neoplastic and non-neoplastic (sputum) cells to take up H{sub 2}TCPP. This was accomplished using spectrofluorimetry and video-enhanced fluorescent microscopy to maximize H{sub 2}TCPP auto-fluorescence across a matrix of substrate conditions, including; reagent concentration, incubation time, temperature, and pH. The second aim was to validate H{sub 2}TCPP on clinical material obtained from subjects monitored in advance of clinical cancer and link those marker results with subsequent histologic confirmation of disease. This was accomplished by applying H{sub 2}TCPP to sputum specimens archived by the Frost Center at Johns Hopkins which maintains a record of the clinical course and long-term follow-up for the patients from whom the specimens were obtained. The authors have used fluorescent immunostaining and flow cytometry to compare uptake of these cytoplasmic Mabs to that of a potential new marker of carcinogenesis, 5, 10, 15, 20 tetrakis (4 carboxyphenyl) porphene (H{sub 2}TCPP). The nuclear uptake of H{sub 2}TCPP was compared to a standard quantitative fluorescent DNA marker (7-AAD).

  4. Photophysical Characterization and in Vitro Phototoxicity Evaluation of 5,10,15,20-Tetra(quinolin-2-yl)porphyrin as a Potential Sensitizer for Photodynamic Therapy.

    PubMed

    Costa, Letícia D; e Silva, Joana de A; Fonseca, Sofia M; Arranja, Cláudia T; Urbano, Ana M; Sobral, Abilio J F N

    2016-03-31

    Photodynamic therapy (PDT) is a selective and minimally invasive therapeutic approach, involving the combination of a light-sensitive compound, called a photosensitizer (PS), visible light and molecular oxygen. The interaction of these per se harmless agents results in the production of reactive species. This triggers a series of cellular events that culminate in the selective destruction of cancer cells, inside which the photosensitizer preferentially accumulates. The search for ideal PDT photosensitizers has been a very active field of research, with a special focus on porphyrins and porphyrin-related macrocycle molecules. The present study describes the photophysical characterization and in vitro phototoxicity evaluation of 5,10,15,20-tetra(quinolin-2-yl)porphyrin (2-TQP) as a potential PDT photosensitizer. Molar absorption coefficients were determined from the corresponding absorption spectrum, the fluorescence quantum yield was calculated using 5,10,15,20-tetraphenylporphyrin (TPP) as a standard and the quantum yield of singlet oxygen generation was determined by direct phosphorescence measurements. Toxicity evaluations (in the presence and absence of irradiation) were performed against HT29 colorectal adenocarcinoma cancer cells. The results from this preliminary study show that the hydrophobic 2-TQP fulfills several critical requirements for a good PDT photosensitizer, namely a high quantum yield of singlet oxygen generation (Φ∆ 0.62), absence of dark toxicity and significant in vitro phototoxicity for concentrations in the micromolar range.

  5. Effects of Heating on Proportions of Azaspiracids 1-10 in Mussels (Mytilus edulis) and Identification of Carboxylated Precursors for Azaspiracids 5, 10, 13, and 15.

    PubMed

    Kilcoyne, Jane; McCarron, Pearse; Hess, Philipp; Miles, Christopher O

    2015-12-30

    Azaspiracids (AZAs) are marine biotoxins that induce human illness following the consumption of contaminated shellfish. European Union regulation stipulates that only raw shellfish are tested, yet shellfish are often cooked prior to consumption. Analysis of raw and heat-treated mussels (Mytilus edulis) naturally contaminated with AZAs revealed significant differences (up to 4.6-fold) in AZA1-3 (1-3) and 6 (6) values due to heat-induced chemical conversions. Consistent with previous studies, high levels of 3 and 6 were detected in some samples that were otherwise below the limit of quantitation before heating. Relative to 1, in heat-treated mussels the average (n = 40) levels of 3 (range, 11-502%) and 6 (range, 3-170%) were 62 and 31%, respectively. AZA4 (4) (range, <1-27%), AZA5 (5) (range, 1-21%), and AZA8 (8) (range, 1-27%) were each ∼5%, whereas AZA7 (7), AZA9 (9), and AZA10 (10) (range, <1-8%) were each under 1.5%. Levels of 5, 10, AZA13 (13), and AZA15 (15) increased after heating, leading to the identification of novel carboxylated AZA precursors in raw shellfish extracts, which were shown by deuterium labeling to be precursors for 5, 10, 13, and 15.

  6. Fine (PM2.5), coarse (PM2.5-10), and metallic elements of suspended particulates for incense burning at Tzu Yun Yen temple in central Taiwan.

    PubMed

    Fang, Guor-Cheng; Chang, Cheng-Nan; Chu, Chia-Chium; Wu, Yuh-Shen; Pi-Cheng Fu, Peter; Chang, Shyh-Chyi; Yang, I-Lin

    2003-06-01

    Ambient suspended particulate concentrations were measured at Tzu Yun Yen temple (120 degrees, 34('), 10(") E; 24 degrees, 16('), 12(") N) in this study. This is representative of incense burning and semi-open sampling sites. The Universal-sampler collected fine and coarse particle material was used to measure suspended particulate concentrations, and sampling periods were from 16/08/2001 to 2/1/2002 at Tzu Yun Yen temple. In addition, metallic element concentrations, compositions of PM(2.5) and PM(2.5-10) for incense burning at Tzu Yun Yen temple were also analyzed in this study. The PM(2.5)/PM(10) ratios ranged between 31% and 87% and averaged 70+/-11% during incense the burning period, respectively. The median metallic element concentration order for these elements is Fe>Zn>Cr>Cd>Pb>Mn>Ni>Cu in fine particles (PM(2.5)) at the Tzu Yun Yen temple sampling site. The median metallic element concentration order for these elements is Fe>Zn>Cr>Pb>Cd>Ni>Mn>Cu in coarse particle (PM(2.5-10)) at the Tzu Yun Yen temple sampling site. Fine particulates (PM(2.5)) are the main portion of PM(10) at Tzu Yun Yen temple in this study. From the point of view of PM(10), these data reflect that the elements Fe, Zn, and Cr were the major elements distributed at Tzu Yun Yen temple in this study.

  7. Depth Analogy: Data-Driven Approach for Single Image Depth Estimation Using Gradient Samples.

    PubMed

    Choi, Sunghwan; Min, Dongbo; Ham, Bumsub; Kim, Youngjung; Oh, Changjae; Sohn, Kwanghoon

    2015-12-01

    Inferring scene depth from a single monocular image is a highly ill-posed problem in computer vision. This paper presents a new gradient-domain approach, called depth analogy, that makes use of analogy as a means for synthesizing a target depth field, when a collection of RGB-D image pairs is given as training data. Specifically, the proposed method employs a non-parametric learning process that creates an analogous depth field by sampling reliable depth gradients using visual correspondence established on training image pairs. Unlike existing data-driven approaches that directly select depth values from training data, our framework transfers depth gradients as reconstruction cues, which are then integrated by the Poisson reconstruction. The performance of most conventional approaches relies heavily on the training RGB-D data used in the process, and such a dependency severely degenerates the quality of reconstructed depth maps when the desired depth distribution of an input image is quite different from that of the training data, e.g., outdoor versus indoor scenes. Our key observation is that using depth gradients in the reconstruction is less sensitive to scene characteristics, providing better cues for depth recovery. Thus, our gradient-domain approach can support a great variety of training range datasets that involve substantial appearance and geometric variations. The experimental results demonstrate that our (depth) gradient-domain approach outperforms existing data-driven approaches directly working on depth domain, even when only uncorrelated training datasets are available. PMID:26529766

  8. MODIS 3 Km Aerosol Product: Applications over Land in an Urban/suburban Region

    NASA Technical Reports Server (NTRS)

    Munchak, L. A.; Levy, R. C.; Mattoo, S.; Remer, L. A.; Holben, B. N.; Schafer, J. S.; Hostetler, C. A.; Ferrare, R. A.

    2013-01-01

    MODerate resolution Imaging Spectroradiometer (MODIS) instruments aboard the Terra and Aqua satellites have provided a rich dataset of aerosol information at a 10 km spatial scale. Although originally intended for climate applications, the air quality community quickly became interested in using the MODIS aerosol data. However, 10 km resolution is not sufficient to resolve local scale aerosol features. With this in mind, MODIS Collection 6 is including a global aerosol product with a 3 km resolution. Here, we evaluate the 3 km product over the Baltimore/Washington D.C., USA, corridor during the summer of 2011, by comparing with spatially dense data collected as part of the DISCOVER-AQ campaign these data were measured by the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL) and a network of 44 sun photometers (SP) spaced approximately 10 km apart. The HSRL instrument shows that AOD can vary by up to 0.2 within a single 10 km MODIS pixel, meaning that higher resolution satellite retrievals may help to characterize aerosol spatial distributions in this region. Different techniques for validating a high-resolution aerosol product against SP measurements are considered. Although the 10 km product is more statistically reliable than the 3 km product, the 3 km product still performs acceptably, with more than two-thirds of MODIS/SP collocations falling within the expected error envelope with high correlation (R > 0.90). The 3 km product can better resolve aerosol gradients and retrieve closer to clouds and shorelines than the 10 km product, but tends to show more significant noise especially in urban areas. This urban degradation is quantified using ancillary land cover data. Overall, we show that the MODIS 3 km product adds new information to the existing set of satellite derived aerosol products and validates well over the region, but due to noise and problems in urban areas, should be treated with some degree of caution.

  9. Moho depth and two discontinuities variation in Taiwan from radial teleseismic receiver functions

    NASA Astrophysics Data System (ADS)

    Ton, C.; Chen, C. H.

    2005-12-01

    In this study, we use data recorded by the stations of Broadband Array in Taiwan for Seismology (BATS) to investigate the depths of major discontinuities of the crust in Taiwan. From the differential times between direct P wave and converted Ps phase and several multiple phases on radial teleseismic receiver function, we determine the Moho depth and the Vp/Vs ratios at these stations. More importantly, we develop a method which can let us use more seismic phases to examine other discontinuities in the crust. Using the arrival times of some specific phases on radial teleseismic receiver function, except for Moho discontinuity, we found that there are two discontinuities ( denoted by discontinuity 1 and discontinuity 2 ) existing in the crust that beneath some of stations. The Moho depth in Taiwan varies from 22 to 39 km and Vp/Vs ratios varies from 1.64~1.87. The deepest Moho depth in Taiwan locates at the Central Mountain Range (CMR) and consistent with the result obtained from gravity survey. The discontinuity 1 and the discontinuity 2 exist clearly in the CMR, in the southern region and the northeastern region of Taiwan. These two discontinuities both become unapparent in the northern region (volcano region) and in the southeastern region (plate convergent area) of Taiwan. The depth of the discontinuity 1 varies from 4.5 to 11 km and while the depth of the discontinuity 2 varies from 12 to 22 km in our estimation. Based on these results, we imply that the discontinuity 1 and 2 are basement and the Conrad discontinuity respectively.

  10. Detection capability of global earthquakes influenced by large intermediate-depth and deep earthquakes

    NASA Astrophysics Data System (ADS)

    Iwata, T.

    2011-12-01

    This study examined the detection capability of the global CMT catalogue immediately after a large intermediate-depth (70 < depth ≤ 300 km) or deep (300 km < depth) earthquake. Iwata [2008, GJI] have revealed that the detection capability is remarkably lower than ordinary one for several hours after the occurrence of a large shallow (depth ≤ 70 km) earthquake. Since the global CMT catalogue plays an important role in studies on global earthquake forecasting or seismicity pattern [e.g., Kagan and Jackson, 2010, Pageoph], the characteristic of the catalogue should be investigated carefully. We stacked global shallow earthquake sequences, which are taken from the global CMT catalogue from 1977 to 2010, after a large intermediate-depth or deep earthquake. Then, we utilized a statistical model representing an observed magnitude-frequency distribution of earthquakes [e.g., Ringdal, 1975, BSSA; Ogata and Katsura, 1993, GJI]. The applied model is a product of the Gutenberg-Richter law and a detection rate function q(M). Following previous studies, the cumulative distribution of the normal distribution was used as q(M). This model enables us to estimate μ, the magnitude where the detection rate of earthquake is 50 per cent. Finally, a Bayesian approach with a piecewise linear approximation [Iwata, 2008, GJI] was applied to this stacked data to estimate the temporal change of μ. Consequently, we found a significantly lowered detection capability after a intermediate-depth or deep earthquake of which magnitude is 6.5 or larger. The lowered detection capability lasts for several hours or one-half day. During this period of low detection capability, a few per cent of M ≥ 6.0 earthquakes or a few tens percent of M ≥ 5.5 earthquakes are undetected in the global CMT catalogue while the magnitude completeness threshold of the catalogue was estimated to be around 5.5 [e.g., Kagan, 2003, PEPI].

  11. Crystallization depth beneath an oceanic detachment fault (ODP Hole 923A, Mid-Atlantic Ridge)

    NASA Astrophysics Data System (ADS)

    Lissenberg, C. Johan; Rioux, Matthew; MacLeod, Christopher J.; Bowring, Samuel A.; Shimizu, Nobumichi

    2016-01-01

    Oceanic detachment faults are increasingly recognized as playing an integral role in the seafloor spreading process at slow and ultraslow spreading mid-ocean ridges, with significant consequences for the architecture of the oceanic lithosphere. Although melt supply is considered to play a critical control on the formation and evolution of oceanic detachments, much less well understood is how melts and faults interact and influence each other. Few direct constraints on the locus and depth of melt emplacement in the vicinity of detachments are available. Gabbros drilled in ODP Hole 923A near the intersection of the Mid-Atlantic Ridge and the Kane transform fault (23°N; the MARK area) represent magmas emplaced into the footwall of such a detachment fault and unroofed by it. We here present U-Pb zircon dates for these gabbros and associated diorite veins which, when combined with a tectonic reconstruction of the area, allow us to calculate the depths at which the melts crystallized. Th-corrected single zircon U-Pb dates from three samples range from 1.138 ± 0.062 to 1.213 ± 0.021 Ma. We find a crystallization depth of 6.4 +1.7/-1.3 km, and estimate that the melts parental to the gabbros were initially emplaced up to 1.5 km deeper, at <8 km below the seafloor. The tectonic reconstruction implies that the detachment fault responsible for the exposure of the sampled sequence likely crossed the ridge axis at depth, suggesting that melt emplacement into the footwall of oceanic detachment faults is an important process. The deep emplacement depth we find associated with "detachment mode" spreading at ˜1.2 Ma appears to be significantly greater than the depth of magma reservoirs during the current "magmatic mode" of spreading in the area, suggesting that the northern MARK segment preserves a recent switch between two temporally distinct modes of spreading with fundamentally different lithospheric architecture.

  12. The palaeosol model of arsenic pollution of groundwater tested along a 32 km traverse across West Bengal, India.

    PubMed

    Hoque, M A; McArthur, J M; Sikdar, P K

    2012-08-01

    The distribution of As-pollution in groundwater of the deltaic aquifers of south-eastern Asia may be controlled by the subsurface distribution of palaeo-channel sediments (As-polluted groundwaters) and palaeo-interfluvial sediments (As-free groundwaters). To test this idea, termed the palaeosol model of As-pollution, we drilled 10 sites, analysed groundwater from 249 shallow wells (screened <107 mbgl), field-tested another 149 for As, and used colour as a guide to the presence or absence of As-pollution in a further 531 wells. Our work was conducted along a 32-km traverse running W to E across southern West Bengal, India. At seven drill sites we logged a palaeo-interfluvial sequence, which occurs as three distinct units that together occupy 20 km of the traverse. These palaeo-interfluvial sequences yield As-free groundwaters from brown sands at depth<100 m. The palaeo-interfluvial sequences are separated by two deep palaeo-channels, which were logged at 3 sites. The palaeo-channel deposits host As-polluted groundwater in grey sands. Our findings confirm the predictions of the palaeosol model of As-pollution. We show again that well-colour can be used both to successfully predict the degree of As-pollution in groundwater, and to locate regions of buried palaeo-interfluve that will yield As-free groundwater for the foreseeable future.

  13. Protective effect of kombucha mushroom (KM) tea on phenol-induced cytotoxicity in albino mice.

    PubMed

    Yapar, Kursad; Cavusoglu, Kultigin; Oruc, Ertan; Yalcin, Emine

    2010-09-01

    The present study was carried out to evaluate the protective role of kombucha mushroom (KM) tea on cytotoxicity induced by phenol (PHE) in mice. We used weight gain and micronucleus (MN) frequency as indicators of cytotoxicity and supported these parameters with pathological findings. The animals were randomly divided into seven groups: (Group I) only tap water (Group II) 1000 microl kg(-1) b. wt KM-tea, (Group III) 35 mg kg(-1) body wt. PHE (Group IV) 35 mg kg(-1) body wt. PHE + 250 microl kg(-1) b. wt KM-tea (Group V) 35 mg kg(-1) b. wt PHE + 500 microl kg(-1) b. wt KM-tea (Group VI) 35 mg kg(-1) b. wt PHE + 750 microl kg(-1) b. wt KM-tea, (Group VII) 35 mg kg(-1) b. wt PHE + 1000 microl kg(-1) b. wt KM-tea, for 20 consecutive days by oral gavage. The results indicated that all KM-tea supplemented mice showed a lower MN frequency than erythrocytes in only PHE-treated group. There was an observable regression on account of lesions in tissues of mice supplemented with different doses of KM-tea in histopathological observations. In conclusion, the KM-tea supplementation decreases cytotoxicity induced by PHE and its protective role is dose-dependent.

  14. Seismic depth conversion vs. structural validation

    NASA Astrophysics Data System (ADS)

    Totake, Yukitsugu; Butler, Rob; Bond, Clare

    2016-04-01

    Interpretation based on seismic reflection data is inherently an uncertain product based on imperfect datasets, with limits in data resolution and spatial extent. This has boosted geologists to use structural validation techniques to verify their seismic interpretations for many years. Structural validation of seismic interpretations should be ideally completed on depth sections, which are converted from time domain using velocities derived from well checkshot survey, seismic velocity analysis, or even estimates. Choices of velocity model critically control the final depth image and hence structural geometry of interpretations that are used as initial datasets for structural validations. However, the depth conversion is never perfectly accurate because of absence of depth constraint. Now, how robust are structural validation techniques to depth conversion uncertainty? Here we explore how structural validation techniques respond to different versions of depth interpretations converted by different velocities. We use a seismic time-based image of a fold-thrust structure in the deepwater Niger Delta to interpret, and convert to depth using three different velocity models: constant velocity (VM1); a single layer having initial velocity v0 at layer top with vertical velocity gradient k (VM2); and three layers having each v0-k set (VM3) below seabed. Forward modelling, automated trishear modelling algorithm called 'inverse trishear modelling' and Groshong's area-depth-strain (ADS) methods are applied to test the structural geometry of the depth-converted interpretations. We find forward modelling and inverse trishear modelling reasonably 'fit' all versions of interpretation, regardless of the velocity model used for depth conversion, with multiple sets of model parameters. On the other hand, only velocity model VM3 'passes' the ADS validation method, with the detachment level interpreted concordant with the depth estimated from excess area analysis, based on interpreted

  15. Source Depth Determination in China Using Intermediate-Period Fundamental Mode Surface Waves

    NASA Astrophysics Data System (ADS)

    Fox, B. D.; Woodhouse, J. H.; Selby, N. D.

    2005-12-01

    The reliable estimation of the depth of shallow earthquakes is a central seismological problem, with few earthquakes in current catalogues having reliably determined depths. In forensic seismology, a trustworthy determination that the source depth exceeds 10km is sufficient to rule out a seismic event as a potential explosion. Source, path and receiver terms are summed to generate fundamental-mode surface-wave synthetic seismograms for earthquakes in north west China. For source and receiver, local modes are calculated using a global 3D model of seismic velocity in the uppermost 400km of the Earth. The path contribution is determined by assuming that the surface waves follow the great-circle between source and receiver. Previous studies have shown that intermediate-period (100s-10s) Rayleigh wave amplitude spectra contain frequency-dependent nulls or notches that are a strong constraint on source depth. Here we present comparisons of fundamental mode data and synthetic amplitude spectra for a number of earthquakes in north-west China along with revised focal mechanisms and source depths.

  16. Testing the use of aeromagnetic data for the determination of Curie depth in California

    USGS Publications Warehouse

    Ross, H.E.; Blakely, R.J.; Zoback, M.D.

    2006-01-01

    Using California as a test region, we have examined the feasibility of using Curie-isotherm depths, estimated from magnetic anomalies, as a proxy for lithospheric thermal structure. Our method follows previous studies by dividing a regional aeromagnetic database into overlapping subregions and analyzing the power-density spectrum of each subregion, but we have improved on previous studies in two important ways: We increase subregion dimensions in a stepwise manner until long-wavelength anomalies are appropriately sampled, and each subregion spectrum determined from the magnetic anomalies is manually fit with a theoretical expression that directly yields the depth to the bottom of the magnetic layer. Using this method, we have obtained Curie-isotherm depths for California that show a general inverse correlation with measured heat flow, as expected. The Coast Ranges of California are characterized by high heat flow (80-85 mW/m2) and shallow Curie depths (20-30 km), whereas the Great Valley has low heat flow (less than 50 mW/m2) and deeper Curie depths (30-45 km). ?? 2006 Society of Exploration Geophysicists.

  17. Accurate Focal Depth Determination of Oceanic Earthquakes Using Water-column Reverberation and Some Implications for the Shrinking Plate Hypothesis

    NASA Astrophysics Data System (ADS)

    Niu, F.; Huang, J.; Gordon, R. G.

    2015-12-01

    Investigation of oceanic earthquakes can play an important role in constraining the lateral and depth variations of the stress and strain-rate fields in oceanic lithosphere and of the thickness of the seismogenic layer as a function of lithosphere age, thereby providing us with critical insight into thermal and dynamic processes associated with the cooling and evolution of oceanic lithosphere. With the goal of estimating hypocentral depths more accurately, we observe clear water reverberations after the direct P wave on teleseismic records of oceanic earthquakes and develop a technique to estimate earthquake depths by using these reverberations. The Z-H grid search method allows the simultaneous determination of the sea floor depth (H) and earthquake depth (Z) with an uncertainty less than 1 km, which compares favorably with alternative approaches. We apply this method to two closely located earthquakes beneath the eastern Pacific. These earthquakes occur in ≈25 Ma-old lithosphere and were previously estimated to have very similar depths of ≈10-12 km. We find that the two events actually occurred at dissimilar depths of 2.5 km and 16.8 km beneath the seafloor, respectively within the oceanic crust and lithospheric mantle. The shallow and deep events are determined to be a thrust and normal earthquake, respectively, indicating that the stress field within the oceanic lithosphere changes from horizontal compression to horizontal extension as depth increases, which is consistent with the prediction of the lithospheric cooling model. Furthermore, we show that the P-axis of the newly investigated thrust-faulting earthquake is roughly perpendicular to that of the previously studied thrust event, consistent with the predictions of the shrinking-plate hypothesis.

  18. Accurate focal depth determination of oceanic earthquakes using water-column reverberation and some implications for the shrinking plate hypothesis

    NASA Astrophysics Data System (ADS)

    Huang, Jianping; Niu, Fenglin; Gordon, Richard G.; Cui, Chao

    2015-12-01

    Investigation of oceanic earthquakes is useful for constraining the lateral and depth variations of the stress and strain-rate fields in oceanic lithosphere, and the thickness of the seismogenic layer as a function of lithosphere age, thereby providing us with critical insight into thermal and dynamic processes associated with the cooling and evolution of oceanic lithosphere. With the goal of estimating hypocentral depths more accurately, we observe clear water reverberations after the direct P wave on teleseismic records of oceanic earthquakes and develop a technique to estimate earthquake depths by using these reverberations. The Z-H grid search method allows the simultaneous determination of the sea floor depth (H) and earthquake depth (Z) with an uncertainty less than 1 km, which compares favorably with alternative approaches. We apply this method to two closely located earthquakes beneath the eastern Pacific. These earthquakes occurred in ∼25 Ma-old lithosphere and were previously estimated to have similar depths of ∼10-12 km. We find that the two events actually occurred at dissimilar depths of 2.5 km and 16.8 km beneath the seafloor, respectively, within the oceanic crust and lithospheric mantle. The shallow and deep events are determined to be a thrust and normal earthquake, respectively, indicating that the stress field within the oceanic lithosphere changes from horizontal deviatoric compression to horizontal deviatoric tension as depth increases, which is consistent with the prediction of lithospheric cooling models. Furthermore, we show that the P-axis of the newly investigated thrust-faulting earthquake is perpendicular to that of the previously studied thrust event, consistent with the predictions of the shrinking-plate hypothesis.

  19. Remotely Measuring Snow Depth in Inaccessible Terrain

    NASA Astrophysics Data System (ADS)

    Dixon, D.; Boon, S.

    2010-12-01

    In watershed-scale studies of snow accumulation, high alpine areas are typically important accumulation areas. While snow depth measurements may not be collected in these regions due to avalanche danger, failing to include them in basin-wide estimates of snow accumulation may lead to large underestimates of basin-scale water yield. We present a new method to measure spatially distributed point snow depths remotely. Previously described methods using terrestrial laser scanning (TLS) systems, airborne light detection and ranging (LiDAR) systems, and hand-held laser distance meters have several limitations related to cost, data processing, and accuracy, thus reducing their applicability. The use of a modern robotic total station attempts to resolve these limitations. Total stations have much greater measurement accuracy than laser distance meters, and are significantly less expensive then TLS and LiDAR systems. Data can be output in common data formats, simplifying data processing and management. Measurement points can also be resampled repeatedly throughout the season with high accuracy and precision. Simple trigonometry is used to convert total station measurements into estimates of snow depth perpendicular to the slope. We present results of remote snow depth measurements using a Leica Geosystems TCRP 1201+ robotic total station. Snow depth estimates from the station are validated against measured depths in a field trial. The method is then applied in a basin-scale study to collect and calculate high elevation snow depth, in combination with traditional snow surveys at lower elevations.

  20. Boundary Depth Information Using Hopfield Neural Network

    NASA Astrophysics Data System (ADS)

    Xu, Sheng; Wang, Ruisheng

    2016-06-01

    Depth information is widely used for representation, reconstruction and modeling of 3D scene. Generally two kinds of methods can obtain the depth information. One is to use the distance cues from the depth camera, but the results heavily depend on the device, and the accuracy is degraded greatly when the distance from the object is increased. The other one uses the binocular cues from the matching to obtain the depth information. It is more and more mature and convenient to collect the depth information of different scenes by stereo matching methods. In the objective function, the data term is to ensure that the difference between the matched pixels is small, and the smoothness term is to smooth the neighbors with different disparities. Nonetheless, the smoothness term blurs the boundary depth information of the object which becomes the bottleneck of the stereo matching. This paper proposes a novel energy function for the boundary to keep the discontinuities and uses the Hopfield neural network to solve the optimization. We first extract the region of interest areas which are the boundary pixels in original images. Then, we develop the boundary energy function to calculate the matching cost. At last, we solve the optimization globally by the Hopfield neural network. The Middlebury stereo benchmark is used to test the proposed method, and results show that our boundary depth information is more accurate than other state-of-the-art methods and can be used to optimize the results of other stereo matching methods.

  1. Analysis of PM10, PM2.5, and PM2 5-10 concentrations in Santiago, Chile, from 1989 to 2001.

    PubMed

    Koutrakis, Petros; Sax, Sonja N; Sarnat, Jeremy A; Coull, Brent; Demokritou, Phil; Oyola, Pedro; Garcia, Javier; Gramsch, Ernesto

    2005-03-01

    Daily particle samples were collected in Santiago, Chile, at four urban locations from January 1, 1989, through December 31, 2001. Both fine PM with da < 2.5 microm (PM2.5) and coarse PM with 2.5 < da < 10 microm (PM2.5-10) were collected using dichotomous samplers. The inhalable particle fraction, PM10, was determined as the sum of fine and coarse concentrations. Wind speed, temperature and relative humidity (RH) were also measured continuously. Average concentrations of PM2.5 for the 1989-2001 period ranged from 38.5 microg/m3 to 53 microg/m3. For PM2.5-10 levels ranged from 35.8-48.2 microg/m3 and for PM10 results were 74.4-101.2 microg/m3 across the four sites. Both annual and daily PM2.5 and PM10 concentration levels exceeded the U.S. National Ambient Air Quality Standards and the European Union concentration limits. Mean PM2.5 levels during the cold season (April through September) were more than twice as high as those observed in the warm season (October through March); whereas coarse particle levels were similar in both seasons. PM concentration trends were investigated using regression models, controlling for site, weekday, month, wind speed, temperature, and RH. Results showed that PM2.5 concentrations decreased substantially, 52% over the 12-year period (1989-2000), whereas PM2.5-10 concentrations increased by approximately 50% in the first 5 years and then decreased by a similar percentage over the following 7 years. These decreases were evident even after controlling for significant climatic effects. These results suggest that the pollution reduction programs developed and implemented by the Comisión Nacional del Medio Ambiente (CONAMA) have been effective in reducing particle levels in the Santiago Metropolitan region. However, particle levels remain high and it is thus imperative that efforts to improve air quality continue.

  2. Cytotoxicity of PM(2.5) and PM(2.5--10) ambient air pollutants assessed by the MTT and the Comet assays.

    PubMed

    Hsiao, W L; Mo, Z Y; Fang, M; Shi, X M; Wang, F

    2000-11-20

    Ambient air particulate matters are classified into two distinct modes in size distribution, namely the coarse and fine particles. Correlation between high particulate concentration and adverse effects on human populations has long been recognized, however, the toxicology of these adverse effects has not been clarified. In the current report, the cytotoxic effects of the solvent-extractable organic compounds (SEOC) from fine particles smaller than 2.5 microm (PM(2.5)) and from coarse particles between 2.5-10 microm (PM(2.5-10)) were studied. Nine 24h consecutive monthly samples were tested to determine the correlation between cytotoxicity and total SEOC in two size fractions of particulate air pollution. Cytotoxicity of SEOC was measured by two micro-scale mammalian cells-based bioassays: the MTT cell proliferation assay, and the Comet assay for the detection of DNA damage. A well-defined mammalian cell line - Rat 6 rodent fibroblast was employed in the study. The SEOC extracts of air particulate matters were sub divided into two equal parts. One part was dissolved in DMSO, the other in KOH/hexane and then conjugated with bovine serum albumin to produce a lipid-soluble fraction for testing. The DMSO fraction would contain mainly the polycyclic aromatic hydrocarbons (PAH), alkanes and alkanols, while the lipid-soluble fraction would be enriched with fatty acids. The results from MTT assay showed that cytotoxicity of the PM(2.5) was much more severe than the PM(2.5-10), suggesting that toxic SEOC were confined to the fine particles. By and large, the DMSO solubles were much more toxic than the lipid solubles. The degree of cytotoxicity of the DMSO soluble samples is positively correlated to the amount of particulates present in the ambient air. For the PM(2.5), the winter samples were significantly more toxic than the summer samples in terms of cell killing, which seemed to be a direct reflection of the total loading of organic matter in the samples. Results from

  3. Improved tilt-depth method for fast estimation of top and bottom depths of magnetic bodies

    NASA Astrophysics Data System (ADS)

    Wang, Yan-Guo; Zhang, Jin; Ge, Kun-Peng; Chen, Xiao; Nie, Feng-Jun

    2016-06-01

    The tilt-depth method can be used to make fast estimation of the top depth of magnetic bodies. However, it is unable to estimate bottom depths and its every inversion point only has a single solution. In order to resolve such weaknesses, this paper presents an improved tilt-depth method based on the magnetic anomaly expression of vertical contact with a finite depth extent, which can simultaneously estimate top and bottom depths of magnetic bodies. In addition, multiple characteristic points are selected on the tilt angle map for joint computation to improve reliability of inversion solutions. Two- and threedimensional model tests show that this improved tilt-depth method is effective in inverting buried depths of top and bottom bodies, and has a higher inversion precision for top depths than the conventional method. The improved method is then used to process aeromagnetic data over the Changling Fault Depression in the Songliao Basin, and inversion results of top depths are found to be more accurate for actual top depths of volcanic rocks in two nearby drilled wells than those using the conventional tilt-depth method.

  4. Monitoring microearthquakes with the San Andreas fault observatory at depth

    USGS Publications Warehouse

    Oye, V.; Ellsworth, W.L.

    2007-01-01

    In 2005, the San Andreas Fault Observatory at Depth (SAFOD) was drilled through the San Andreas Fault zone at a depth of about 3.1 km. The borehole has subsequently been instrumented with high-frequency geophones in order to better constrain locations and source processes of nearby microearthquakes that will be targeted in the upcoming phase of SAFOD. The microseismic monitoring software MIMO, developed by NORSAR, has been installed at SAFOD to provide near-real time locations and magnitude estimates using the high sampling rate (4000 Hz) waveform data. To improve the detection and location accuracy, we incorporate data from the nearby, shallow borehole (???250 m) seismometers of the High Resolution Seismic Network (HRSN). The event association algorithm of the MIMO software incorporates HRSN detections provided by the USGS real time earthworm software. The concept of the new event association is based on the generalized beam forming, primarily used in array seismology. The method requires the pre-computation of theoretical travel times in a 3D grid of potential microearthquake locations to the seismometers of the current station network. By minimizing the differences between theoretical and observed detection times an event is associated and the location accuracy is significantly improved.

  5. Contrails of Small and Very Large Optical Depth

    NASA Technical Reports Server (NTRS)

    Atlas, David; Wang, Zhien

    2010-01-01

    This work deals with two kinds of contrails. The first comprises a large number of optically thin contrails near the tropopause. They are mapped geographically using a lidar to obtain their height and a camera to obtain azimuth and elevation. These high-resolution maps provide the local contrail geometry and the amount of optically clear atmosphere. The second kind is a single trail of unprecedentedly large optical thickness that occurs at a lower height. The latter was observed fortuitously when an aircraft moving along the wind direction passed over the lidar, thus providing measurements for more than 3 h and an equivalent distance of 620 km. It was also observed by Geostationary Operational Environmental Satellite (GOES) sensors. The lidar measured an optical depth of 2.3. The corresponding extinction coefficient of 0.023 per kilometer and ice water content of 0.063 grams per cubic meter are close to the maximum values found for midlatitude cirrus. The associated large radar reflectivity compares to that measured by ultrasensitive radar, thus providing support for the reality of the large optical depth.

  6. Exploratory depth-of-burst experiments

    SciTech Connect

    Reichenbach, H.; Behrens, K.; Kuhl, A.

    1991-12-12

    This report describes the first small-scale explosion experiments with aerated grout (i.e., YTONG). Apart from data referring to crater depth and volume versus depth of burst (DOB), isobaric DOB curves in the range of 1.5 psi {le} p {le} 15 psi were established. The comparison with previous HOB values shows that the ground range to a given overpressure is considerably reduced with increasing depth of burst. The authors plan to continue the airblast investigations with different types of soil materials.

  7. Control of electrode depth in electroslag remelting

    DOEpatents

    Melgaard, David K.; Shelmidine, Gregory J.; Damkroger, Brian K.

    2002-01-01

    A method of and apparatus for controlling an electroslag remelting furnace by driving the electrode at a nominal speed based upon melting rate and geometry while making minor proportional adjustments based on a measured metric of the electrode immersion depth. Electrode drive speed is increased if a measured metric of electrode immersion depth differs from a set point by a predetermined amount, indicating that the tip is too close to the surface of a slag pool. Impedance spikes are monitored to adjust the set point for the metric of electrode immersion depth based upon one or more properties of the impedance spikes.

  8. Evaluation of the variable depth resolution of active dynamic thermography on human skin

    NASA Astrophysics Data System (ADS)

    Prindeze, Nicholas J.; Hoffman, Hilary A.; Carney, Bonnie C.; Moffatt, Lauren T.; Loew, Murray H.; Shupp, Jeffrey W.

    2015-06-01

    Active dynamic thermography (ADT) is an imaging technique capable of characterizing the non-homogenous thermal conductance of damaged tissues. The purpose of this study was to determine optimal stimulation parameters and quantify the optical resolution of ADT through various depths of human skin. Excised tissue from plastic surgery operations was collected immediately following excision. A total of 12 thin to thick split-thickness grafts were harvested from 3 patients. Grafts were placed on top of a 3D printed resolution chart and thermal stimulation was applied from a 300W halogen lamp array for between 0.5-10 seconds to determine optimal parameters. Video was captured with a thermal camera, and analysis was performed by reconstructing an image from thermal gradients. In this study ADT resolved 0.445+/-0 lp/mm at a depth of 0.010", 0.356+/-0.048 lp/mm at a depth of 0.015", 0.334+/-0.027 lp/mm at a depth of 0.020" and 0.265+/-0.022 lp/mm at a depth of 0.025". The stimulus energy required for maximum resolution at each depth was 3- 4s, 8s, 12s and 12s respectively. ADT is a sensitive technique for imaging dermal structure, capable of resolving detail as fine as 1124 μm, 1427 μm, 1502 μm and 1893 μm in thin to thick split-thickness skin grafts respectively. This study has characterized a correlation between stimulus input and maximal resolution at differing depths of skin. It has also defined the functional imaging depth of ADT to below the sub-cutis, well below conventional spectrophotometric techniques.

  9. CALIPSO and MODIS Observations of Increases in Aerosol Optical Depths near Marine Stratocumulus

    NASA Astrophysics Data System (ADS)

    Coakley, J. A.; Tahnk, W. R.

    2009-12-01

    Aerosols not only affect droplet sizes and number concentrations in marine stratocumulus but in turn the near cloud environment gives rise to changes in the aerosol particle concentrations and sizes. In addition, the clouds serve as reflectors that illuminate the adjacent cloud-free air. This extra illumination leads to overestimates of aerosol optical depths and fine mode fractions retrieved from multispectral satellite imagery. Large cloud-free ocean regions bounded on both ends, or if sufficiently large (>100 km), on at least one end by layers of marine stratocumulus, as deduced from CALIPSO lidar returns, were examined to deduce the effects of the clouds on the properties of nearby aerosols. CALIPSO aerosol optical depths composited for more than a year and covering the global oceans, 60°S-60°N, reveal that the fractional increase in aerosol optical depth in going from a cloud-free 5-km region more than 10 to 15 km from a cloud boundary to one adjacent the clouds is 10%-15% at both 532 and 1064 nm for both daytime and nighttime observations. All of the changes are statistically significant at the 90% confidence level or greater. The associated reduction in the 532/1064 Ånsgtröm Exponent is 0.023 for the nighttime observations, but owing to a poorer signal to noise ratio, no change in the Exponent is detected for the daytime observations. For comparison, the MODIS aerosol optical depths collocated with the daytime CALIPSO optical depths suggest that the fractional increases in aerosol optical depths in going from a cloud-free 10-km region 15 km from a cloud boundary to one adjacent the clouds is about 5% at both 550 and 850 nm. The associated reduction in the 550/850 Ånsgtröm Exponent is 0.053. The changes in aerosol properties die away within 10 to 20 km from the marine stratocumulus. The increases in aerosol scattering and reductions in Ånsgtröm Exponent suggest that near the clouds, the aerosol particles become larger. The fine mode fraction found in

  10. Constraining shallow seismic event depth via synthetic modeling for Expert Technical Analysis at the IDC

    NASA Astrophysics Data System (ADS)

    Stachnik, J.; Rozhkov, M.; Baker, B.; Bobrov, D.; Friberg, P. A.

    2015-12-01

    Depth of event is an important criterion of seismic event screening at the International Data Center, CTBTO. However, a thorough determination of the event depth can be conducted mostly through special analysis because the IDC's Event Definition Criteria is based, in particular, on depth estimation uncertainties. This causes a large number of events in the Reviewed Event Bulletin to have depth constrained to the surface. When the true origin depth is greater than that reasonable for a nuclear test (3 km based on existing observations), this may result in a heavier workload to manually distinguish between shallow and deep events. Also, IDC depth criterion is not applicable to the events with the small t(pP-P) travel time difference, which is the case of the nuclear test. Since the shape of the first few seconds of signal of very shallow events is very sensitive to the presence of the depth phase, cross correlation between observed and theoretic seismogram can provide an estimate for the depth of the event, and so provide an expansion to the screening process. We exercised this approach mostly with events at teleseismic and partially regional distances. We found that such approach can be very efficient for the seismic event screening process, with certain caveats related mostly to the poorly defined crustal models at source and receiver which can shift the depth estimate. We used adjustable t* teleseismic attenuation model for synthetics since this characteristic is not determined for most of the rays we studied. We studied a wide set of historical records of nuclear explosions, including so called Peaceful Nuclear Explosions (PNE) with presumably known depths, and recent DPRK nuclear tests. The teleseismic synthetic approach is based on the stationary phase approximation with Robert Herrmann's hudson96 program, and the regional modelling was done with the generalized ray technique by Vlastislav Cerveny modified to the complex source topography.

  11. Using a fixed-wing UAS to map snow depth distribution: an evaluation at peak accumulation

    NASA Astrophysics Data System (ADS)

    De Michele, Carlo; Avanzi, Francesco; Passoni, Daniele; Barzaghi, Riccardo; Pinto, Livio; Dosso, Paolo; Ghezzi, Antonio; Gianatti, Roberto; Della Vedova, Giacomo

    2016-03-01

    We investigate snow depth distribution at peak accumulation over a small Alpine area ( ˜ 0.3 km2) using photogrammetry-based surveys with a fixed-wing unmanned aerial system (UAS). These devices are growing in popularity as inexpensive alternatives to existing techniques within the field of remote sensing, but the assessment of their performance in Alpine areas to map snow depth distribution is still an open issue. Moreover, several existing attempts to map snow depth using UASs have used multi-rotor systems, since they guarantee higher stability than fixed-wing systems. We designed two field campaigns: during the first survey, performed at the beginning of the accumulation season, the digital elevation model of the ground was obtained. A second survey, at peak accumulation, enabled us to estimate the snow depth distribution as a difference with respect to the previous aerial survey. Moreover, the spatial integration of UAS snow depth measurements enabled us to estimate the snow volume accumulated over the area. On the same day, we collected 12 probe measurements of snow depth at random positions within the case study to perform a preliminary evaluation of UAS-based snow depth. Results reveal that UAS estimations of point snow depth present an average difference with reference to manual measurements equal to -0.073 m and a RMSE equal to 0.14 m. We have also explored how some basic snow depth statistics (e.g., mean, standard deviation, minima and maxima) change with sampling resolution (from 5 cm up to ˜ 100 m): for this case study, snow depth standard deviation (hence coefficient of variation) increases with decreasing cell size, but it stabilizes for resolutions smaller than 1 m. This provides a possible indication of sampling resolution in similar conditions.

  12. Glass Forming Ability and Kinetic Characters of Paramagnetic Nd60Co40-xAlx(x=5, 10, 15) Bulk Metallic Glasses

    NASA Astrophysics Data System (ADS)

    Xia, L.; Dong, Y. D.

    Paramagnetic Nd60Co40-xAlx(x=5, 10, 15) bulk metallic glasses (BMGs) were prepared in the shape of rods 2 mm in diameter by suction casting. The ternary alloys have shown distinct glass transitions in Differential Scanning Calorimetry (DSC) measurements and excellent glass-forming ability. The glass transition and crystallization behaviors as well as their kinetics have been studied. The reduced glass transition temperature and the supercooled liquid region of the alloys were found to increase with the increasing content of Al. The role of Al was discussed. The parameter γ defined by Liu et al. was employed to discuss the glass-forming ability of the alloys and the critical cooling rates as well as the critical section thickness of the alloys were predicted accordingly.

  13. Comparison between 5,10,15,20-tetraaryl- and 5,15-diarylporphyrins as photosensitizers: synthesis, photodynamic activity, and quantitative structure-activity relationship modeling.

    PubMed

    Banfi, Stefano; Caruso, Enrico; Buccafurni, Loredana; Murano, Roberto; Monti, Elena; Gariboldi, Marzia; Papa, Ester; Gramatica, Paola

    2006-06-01

    The synthesis of a panel of seven nonsymmetric 5,10,15,20-tetraarylporphyrins, 13 symmetric and nonsymmetric 5,15-diarylporphyrins, and one 5,15-diarylchlorin is described. In vitro photodynamic activities on HCT116 human colon adenocarcinoma cells were evaluated by standard cytotoxicity assays. A predictive quantitative structure-activity relationship (QSAR) regression model, based on theoretical holistic molecular descriptors, of a series of 34 tetrapyrrolic photosensitizers (PSs), including the 24 compounds synthesized in this work, was developed to describe the relationship between structural features and photodynamic activity. The present study demonstrates that structural features significantly influence the photodynamic activity of tetrapyrrolic derivatives: diaryl compounds were more active with respect to the tetraarylporphyrins, and among the diaryl derivatives, hydroxy-substituted compounds were more effective than the corresponding methoxy-substituted ones. Furthermore, three monoarylporphyrins, isolated as byproducts during diarylporphyrin synthesis, were considered for both photodynamic and QSAR studies; surprisingly they were found to be particularly active photosensitizers.

  14. 5,10-Methylenetetrahydrofolate reductase polymorphisms and pharmacogenetics: a new role of single nucleotide polymorphisms in the folate metabolic pathway in human health and disease.

    PubMed

    Kim, Young-In

    2005-11-01

    Knowledge about the role of folate, a water-soluble B vitamin, and single nucleotide polymorphisms (SNPs) in the folate metabolic pathway in human health and disease has been rapidly expanding. Recently, functionally significant SNPs in 5,10-methylenetetrahydrofolate reductase (MTHFR), a critical enzyme for intracellular folate homeostasis and metabolism, have been identified and characterized. An emerging body of in vitro and clinical evidence suggests that these MTHFR SNPs may be an important pharmacogenetic determinant of predicting response to and toxicity of methotrexate and 5-fluorouracil-based cancer and anti-inflammatory treatments because of their well-defined and highly relevant biochemical effects on intracellular folate composition and one-carbon transfer reactions.

  15. Photodynamic antimicrobial chemotherapy activity of (5,10,15,20-tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III).

    PubMed

    Managa, Muthumuni; Amuhaya, Edith K; Nyokong, Tebello

    2015-12-01

    (5,10,15,20-Tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III) (complex 1) was conjugated to platinum nanoparticles (PtNPs) (represented as 1-PtNPs). The resulting conjugate showed 18 nm red shift in the Soret band when compared to 1 alone. Complex 1 and 1-PtNPs showed promising photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus, Escherichia coli and Candida albicans in solution where the log reductions obtained were 4.92, 3.76, and 3.95, respectively for 1-PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 1-PtNPs in DMF while that of 1 was 0.52 in the same solvent. This resulted in improved PACT activity for 1-PtNPs compared to 1 alone.

  16. Oxyfunctionalization of unactivated C-H bonds in triterpenoids with tert-butylhydroperoxide catalyzed by meso-5,10,15,20-tetramesitylporphyrinate osmium(II) carbonyl complex.

    PubMed

    Ogawa, Shoujiro; Wakatsuki, Yasuo; Makino, Mitsuko; Fujimoto, Yasuo; Yasukawa, Ken; Kikuchi, Takashi; Ukiya, Motohiko; Akihisa, Toshihiro; Iida, Takashi

    2010-02-01

    A system consisting of meso-5,10,15,20-tetramesitylporphyrinate osmium(II) carbonyl complex [Os(TMP)CO] as a precatalyst and tert-butylhydroperoxide (TBHP) as an oxygen donor is shown to be an efficient, regioselective oxidant system for the allylic oxidation, ketonization and hydroxylation of unactivated C-H bonds in a series of the peracetate derivatives of penta- and tetracyclic triterpenoids. Treatment of the substrates with this oxidant system afforded a variety of novel or scarce oxygenated derivatives in one-step. Structures of the isolated components, after chromatographic separation, were determined by spectroscopic methods including GC-MS and shift-correlated 2D-NMR techniques. Factors governing the regioselectivity and the possible mechanism for the oxyfunctionalization of the unactivated carbons are also discussed.

  17. An in vitro enzymatic assay to measure transcription inhibition by gallium(III) and H3 5,10,15-tris(pentafluorophenyl)corroles.

    PubMed

    Tang, Grace Y; Pribisko, Melanie A; Henning, Ryan K; Lim, Punnajit; Termini, John; Gray, Harry B; Grubbs, Robert H

    2015-03-18

    Chemotherapy often involves broad-spectrum cytotoxic agents with many side effects and limited targeting. Corroles are a class of tetrapyrrolic macrocycles that exhibit differential cytostatic and cytotoxic properties in specific cell lines, depending on the identities of the chelated metal and functional groups. The unique behavior of functionalized corroles towards specific cell lines introduces the possibility of targeted chemotherapy. Many anticancer drugs are evaluated by their ability to inhibit RNA transcription. Here we present a step-by-step protocol for RNA transcription in the presence of known and potential inhibitors. The evaluation of the RNA products of the transcription reaction by gel electrophoresis and UV-Vis spectroscopy provides information on inhibitive properties of potential anticancer drug candidates and, with modifications to the assay, more about their mechanism of action. Little is known about the molecular mechanism of action of corrole cytotoxicity. In this experiment, we consider two corrole compounds: gallium(III) 5,10,15-(tris)pentafluorophenylcorrole (Ga(tpfc)) and freebase analogue 5,10,15-(tris)pentafluorophenylcorrole (tpfc). An RNA transcription assay was used to examine the inhibitive properties of the corroles. Five transcription reactions were prepared: DNA treated with Actinomycin D, triptolide, Ga(tpfc), tpfc at a [complex]:[template DNA base] ratio of 0.01, respectively, and an untreated control. The transcription reactions were analyzed after 4 hr using agarose gel electrophoresis and UV-Vis spectroscopy. There is clear inhibition by Ga(tpfc), Actinomycin D, and triptolide. This RNA transcription assay can be modified to provide more mechanistic detail by varying the concentrations of the anticancer complex, DNA, or polymerase enzyme, or by incubating the DNA or polymerase with the complexes prior to RNA transcription; these modifications would differentiate between an inhibition mechanism involving the DNA or the enzyme

  18. Changes in Body Mass, Hydration and Electrolytes Following a 161-km Endurance Race

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: To examine electrolyte concentrations and changes in body mass and total body water (TBW) during a 161-km ultra-marathon, and relate these to finish time and incidence of hyponatremia. Methods: Subjects were recruited from the 161-km 2008 Rio Del Lago Endurance Race. Body mass, TBW, and s...

  19. Draft Genome Sequence of the Bordetella bronchiseptica Swine Isolate KM22.

    PubMed

    Nicholson, Tracy L; Shore, Sarah M; Bayles, Darrell O; Register, Karen B; Kingsley, Robert A

    2014-01-01

    Bordetella bronchiseptica swine isolate KM22 has been used in experimental infections of swine as a model of clinical B. bronchiseptica infections within swine herds and to study host-to-host transmission. Here we report the draft genome sequence of KM22. PMID:25013141

  20. Acute prior heavy strength exercise bouts improve the 20-km cycling time trial performance.

    PubMed

    Silva, Renato A S; Silva-Júnior, Fernando L; Pinheiro, Fabiano A; Souza, Patrícia F M; Boullosa, Daniel A; Pires, Flávio O

    2014-09-01

    This study verified if a prior 5 repetition maximum (5RM) strength exercise would improve the cycling performance during a 20-km cycling time trial (TT20km). After determination of the 5RM leg press exercise load, 11 trained cyclists performed a TT20km in a control condition and 10-minute after 4 sets of 5RM strength exercise bouts (potentiation condition). Oxygen uptake, blood lactate concentration, ratings of perceived exertion (RPE), and power output data were recorded during the TT20km. Cycling economy index was assessed before the TT20km, and pacing strategy was analyzed assuming a "J-shaped" power output distribution profile. Results were a 6.1% reduction (p ≤ 0.05) in the time to complete the TT20km, a greater cycling economy (p < 0.01), and power output in the first 10% of the TT20km (i.e., trend; p = 0.06) in the potentiation condition. However, no differences were observed in pacing strategy, physiological parameters, and RPE between the conditions. These results suggest that 5RM strength exercise bouts improve the performance in a subsequent TT20km.

  1. A Co-Creation Blended KM Model for Cultivating Critical-Thinking Skills

    ERIC Educational Resources Information Center

    Yeh, Yu-chu

    2012-01-01

    Both critical thinking (CT) and knowledge management (KM) skills are necessary elements for a university student's success. Therefore, this study developed a co-creation blended KM model to cultivate university students' CT skills and to explore the underlying mechanisms for achieving success. Thirty-one university students participated in this…

  2. Draft genome sequence of the Bordetella bronchiseptica swine isolate KM22

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bordetella bronchiseptica swine isolate KM22 has been used in experimental infections of swine as a model of clinical B. bronchiseptica infections within swine herds and to study host-to-host transmission. Here we report the draft genome sequence of KM22....

  3. Draft Genome Sequence of the Bordetella bronchiseptica Swine Isolate KM22.

    PubMed

    Nicholson, Tracy L; Shore, Sarah M; Bayles, Darrell O; Register, Karen B; Kingsley, Robert A

    2014-01-01

    Bordetella bronchiseptica swine isolate KM22 has been used in experimental infections of swine as a model of clinical B. bronchiseptica infections within swine herds and to study host-to-host transmission. Here we report the draft genome sequence of KM22.

  4. Capturing Motion and Depth Before Cinematography.

    PubMed

    Wade, Nicholas J

    2016-01-01

    Visual representations of biological states have traditionally faced two problems: they lacked motion and depth. Attempts were made to supply these wants over many centuries, but the major advances were made in the early-nineteenth century. Motion was synthesized by sequences of slightly different images presented in rapid succession and depth was added by presenting slightly different images to each eye. Apparent motion and depth were combined some years later, but they tended to be applied separately. The major figures in this early period were Wheatstone, Plateau, Horner, Duboscq, Claudet, and Purkinje. Others later in the century, like Marey and Muybridge, were stimulated to extend the uses to which apparent motion and photography could be applied to examining body movements. These developments occurred before the birth of cinematography, and significant insights were derived from attempts to combine motion and depth. PMID:26684420

  5. Capturing Motion and Depth Before Cinematography.

    PubMed

    Wade, Nicholas J

    2016-01-01

    Visual representations of biological states have traditionally faced two problems: they lacked motion and depth. Attempts were made to supply these wants over many centuries, but the major advances were made in the early-nineteenth century. Motion was synthesized by sequences of slightly different images presented in rapid succession and depth was added by presenting slightly different images to each eye. Apparent motion and depth were combined some years later, but they tended to be applied separately. The major figures in this early period were Wheatstone, Plateau, Horner, Duboscq, Claudet, and Purkinje. Others later in the century, like Marey and Muybridge, were stimulated to extend the uses to which apparent motion and photography could be applied to examining body movements. These developments occurred before the birth of cinematography, and significant insights were derived from attempts to combine motion and depth.

  6. Apparent extended body motions in depth

    NASA Technical Reports Server (NTRS)

    Hecht, Heiko; Proffitt, Dennis R.

    1991-01-01

    Five experiments were designed to investigate the influence of three-dimensional (3-D) orientation change on apparent motion. Projections of an orientation-specific 3-D object were sequentially flashed in different locations and at different orientations. Such an occurrence could be resolved by perceiving a rotational motion in depth around an axis external to the object. Consistent with this proposal, it was found that observers perceived curved paths in depth. Although the magnitude of perceived trajectory curvature often fell short of that required for rotational motions in depth (3-D circularity), judgments of the slant of the virtual plane on which apparent motions occurred were quite close to the predictions of a model that proposes circular paths in depth.

  7. Water depth estimation with ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Ross, D. S.

    1973-01-01

    Contrast-enhanced 9.5 inch ERTS-1 images were produced for an investigation on ocean water color. Such images lend themselves to water depth estimation by photographic and electronic density contouring. MSS-4 and -5 images of the Great Bahama Bank were density sliced by both methods. Correlation was found between the MSS-4 image and a hydrographic chart at 1:467,000 scale, in a number of areas corresponding to water depth of less than 2 meters, 5 to 10 meters and 10 to about 20 meters. The MSS-5 image was restricted to depths of about 2 meters. Where reflective bottom and clear water are found, ERTS-1 MSS-4 images can be used with density contouring by electronic or photographic methods for estimating depths to 5 meters within about one meter.

  8. Mars: Crustal pore volume, cryospheric depth, and the global occurrence of groundwater

    NASA Technical Reports Server (NTRS)

    Clifford, Stephen M.

    1987-01-01

    It is argued that most of the Martian hydrosphere resides in a porous outer layer of crust that, based on a lunar analogy, appears to extend to a depth of about 10 km. The total pore volume of this layer is sufficient to store the equivalent of a global ocean of water some 500 to 1500 m deep. Thermal modeling suggests that about 300 to 500 m of water could be stored as ice within the crust. Any excess must exist as groundwater.

  9. Cape Canaveral, Florida range reference atmosphere 0-70 km altitude

    NASA Technical Reports Server (NTRS)

    Tingle, A. (Editor)

    1983-01-01

    The RRA contains tabulations for monthly and annual means, standard deviations, skewness coefficients for wind speed, pressure temperature, density, water vapor pressure, virtual temperature, dew-point temperature, and the means and standard deviations for the zonal and meridional wind components and the linear (product moment) correlation coefficient between the wind components. These statistical parameters are tabulated at the station elevation and at 1 km intervals from sea level to 30 km and at 2 km intervals from 30 to 90 km altitude. The wind statistics are given at approximately 10 m above the station elevations and at altitudes with respect to mean sea level thereafter. For those range sites without rocketsonde measurements, the RRAs terminate at 30 km altitude or they are extended, if required, when rocketsonde data from a nearby launch site are available. There are four sets of tables for each of the 12 monthly reference periods and the annual reference period.

  10. Reference surfaces for bridge scour depths

    USGS Publications Warehouse

    Landers, Mark N.; Mueller, David S.

    1993-01-01

    Depth of scour is measured as the vertical distance between scoured channel geometry and a measurement reference surface. A scour depth measurement can have a wide range depending on the method used to establish the reference surface. A consistent method to establish reference surfaces for bridge scour measurements is needed to facilitate transferability of scour data an scour analyses. This paper describes and evaluates techniques for establishing reference surfaces from which local and contraction scour are measured.

  11. RGB-D depth-map restoration using smooth depth neighborhood supports

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Xue, Haoyang; Yu, Zhongjie; Wu, Qiang; Yang, Jie

    2015-05-01

    A method to restore the depth map of an RGB-D image using smooth depth neighborhood (SDN) supports is presented. The SDN supports are computed based on the corresponding color image of the depth map. Compared with the most widely used square supports, the proposed SDN supports can well-capture the local structure of the object. Only pixels with similar depth values are allowed to be included in the support. We combine our SDN supports with the joint bilateral filter (JBF) to form the SDN-JBF and use it to restore depth maps. Experimental results show that our SDN-JBF can not only rectify the misaligned depth pixels but also preserve sharp depth discontinuities.

  12. Depth-aware image seam carving.

    PubMed

    Shen, Jianbing; Wang, Dapeng; Li, Xuelong

    2013-10-01

    Image seam carving algorithm should preserve important and salient objects as much as possible when changing the image size, while not removing the secondary objects in the scene. However, it is still difficult to determine the important and salient objects that avoid the distortion of these objects after resizing the input image. In this paper, we develop a novel depth-aware single image seam carving approach by taking advantage of the modern depth cameras such as the Kinect sensor, which captures the RGB color image and its corresponding depth map simultaneously. By considering both the depth information and the just noticeable difference (JND) model, we develop an efficient JND-based significant computation approach using the multiscale graph cut based energy optimization. Our method achieves the better seam carving performance by cutting the near objects less seams while removing distant objects more seams. To the best of our knowledge, our algorithm is the first work to use the true depth map captured by Kinect depth camera for single image seam carving. The experimental results demonstrate that the proposed approach produces better seam carving results than previous content-aware seam carving methods. PMID:23893762

  13. Crack depth determination with inductive thermography

    NASA Astrophysics Data System (ADS)

    Oswald-Tranta, B.; Schmidt, R.

    2015-05-01

    Castings, forgings and other steel products are nowadays usually tested with magnetic particle inspection, in order to detect surface cracks. An alternative method is active thermography with inductive heating, which is quicker, it can be well automated and as in this paper presented, even the depth of a crack can be estimated. The induced eddy current, due to its very small penetration depth in ferro-magnetic materials, flows around a surface crack, heating this selectively. The surface temperature is recorded during and after the short inductive heating pulse with an infrared camera. Using Fourier transformation the whole IR image sequence is evaluated and the phase image is processed to detect surface cracks. The level and the local distribution of the phase around a crack correspond to its depth. Analytical calculations were used to model the signal distribution around cracks with different depth and a relationship has been derived between the depth of a crack and its phase value. Additionally, also the influence of the heating pulse duration has been investigated. Samples with artificial and with natural cracks have been tested. Results are presented comparing the calculated and measured phase values depending on the crack depth. Keywords: inductive heating, eddy current, infrared

  14. Molecular depth profiling by wedged crater beveling.

    PubMed

    Mao, Dan; Lu, Caiyan; Winograd, Nicholas; Wucher, Andreas

    2011-08-15

    Time-of-flight secondary ion mass spectrometry and atomic force microscopy are employed to characterize a wedge-shaped crater eroded by a 40-keV C(60)(+) cluster ion beam on an organic film of Irganox 1010 doped with Irganox 3114 delta layers. From an examination of the resulting surface, the information about depth resolution, topography, and erosion rate can be obtained as a function of crater depth for every depth in a single experiment. It is shown that when measurements are performed at liquid nitrogen temperature, a constant erosion rate and reduced bombardment induced surface roughness is observed. At room temperature, however, the erosion rate drops by ∼(1)/(3) during the removal of the 400 nm Irganox film and the roughness gradually increased to from 1 nm to ∼4 nm. From SIMS lateral images of the beveled crater and AFM topography results, depth resolution was further improved by employing glancing angles of incidence and lower primary ion beam energy. Sub-10 nm depth resolution was observed under the optimized conditions on a routine basis. In general, we show that the wedge-crater beveling is an important tool for elucidating the factors that are important for molecular depth profiling experiments.

  15. Performance of scalable coding in depth domain

    NASA Astrophysics Data System (ADS)

    Sjöström, Mårten; Karlsson, Linda S.

    2010-02-01

    Common autostereoscopic 3D displays are based on multi-view projection. The diversity of resolutions and number of views of such displays implies a necessary flexibility of 3D content formats in order to make broadcasting efficient. Furthermore, distribution of content over a heterogeneous network should adapt to an available network capacity. Present scalable video coding provides the ability to adapt to network conditions; it allows for quality, temporal and spatial scaling of 2D video. Scalability for 3D data extends this list to the depth and the view domains. We have introduced scalability with respect to depth information. Our proposed scheme is based on the multi-view-plus-depth format where the center view data are preserved, and side views are extracted in enhancement layers depending on depth values. We investigate the performance of various layer assignment strategies: number of layers, and distribution of layers in depth, either based on equal number of pixels or histogram characteristics. We further consider the consequences to variable distortion due to encoder parameters. The results are evaluated considering their overall distortion verses bit rate, distortion per enhancement layer, as well as visual quality appearance. Scalability with respect to depth (and views) allows for an increased number of quality steps; the cost is a slight increase of required capacity for the whole sequence. The main advantage is, however, an improved quality for objects close to the viewer, even if overall quality is worse.

  16. Depth dependence of vascular fluorescence imaging

    PubMed Central

    Davis, Mitchell A.; Shams Kazmi, S. M.; Ponticorvo, Adrien; Dunn, Andrew K.

    2011-01-01

    In vivo surface imaging of fluorescently labeled vasculature has become a widely used tool for functional brain imaging studies. Techniques such as phosphorescence quenching for oxygen tension measurements and indocyanine green fluorescence for vessel perfusion monitoring rely on surface measurements of vascular fluorescence. However, the depth dependence of the measured fluorescence signals has not been modeled in great detail. In this paper, we investigate the depth dependence of the measured signals using a three-dimensional Monte Carlo model combined with high resolution vascular anatomy. We found that a bulk-vascularization assumption to modeling the depth dependence of the signal does not provide an accurate picture of penetration depth of the collected fluorescence signal in most cases. Instead the physical distribution of microvasculature, the degree of absorption difference between extravascular and intravascular space, and the overall difference in absorption at the excitation and emission wavelengths must be taken into account to determine the depth penetration of the fluorescence signal. Additionally, we found that using targeted illumination can provide for superior surface vessel sensitivity over wide-field illumination, with small area detection offering an even greater amount of sensitivity to surface vasculature. Depth sensitivity can be enhanced by either increasing the detector area or increasing the illumination area. Finally, we see that excitation wavelength and vessel size can affect intra-vessel sampling distribution, as well as the amount of signal that originates from inside the vessel under targeted illumination conditions. PMID:22162824

  17. Motion parallax thresholds for unambiguous depth perception.

    PubMed

    Holmin, Jessica; Nawrot, Mark

    2015-10-01

    The perception of unambiguous depth from motion parallax arises from the neural integration of retinal image motion and extra-retinal eye movement signals. It is only recently that these parameters have been articulated in the form of the motion/pursuit ratio. In the current study, we explored the lower limits of the parameter space in which observers could accurately perform near/far relative depth-sign discriminations for a translating random-dot stimulus. Stationary observers pursued a translating random dot stimulus containing relative image motion. Their task was to indicate the location of the peak in an approximate square-wave stimulus. We measured thresholds for depth from motion parallax, quantified as motion/pursuit ratios, as well as lower motion thresholds and pursuit accuracy. Depth thresholds were relatively stable at pursuit velocities 5-20 deg/s, and increased at lower and higher velocities. The pattern of results indicates that minimum motion/pursuit ratios are limited by motion and pursuit signals, both independently and in combination with each other. At low and high pursuit velocities, depth thresholds were limited by inaccurate pursuit signals. At moderate pursuit velocities, depth thresholds were limited by motion signals.

  18. Global Investigation of the Mg Atom and ion Layers using SCIAMACHY/Envisat Observations between 70 km and 150 km Altitude and WACCM-MG Model Results

    NASA Technical Reports Server (NTRS)

    Langowski, M.; vonSavigny, C.; Burrows, J. P.; Feng, W.; Plane, J. M. C.; Marsh, D. R.; Janches, Diego; Sinnhuber, M.; Aikin, A. C.

    2014-01-01

    Mg and Mg+ concentration fields in the upper mesosphere/lower thermosphere (UMLT) region are retrieved from SCIAMACHY/Envisat limb measurements of Mg and Mg+ dayglow emissions using a 2-D tomographic retrieval approach. The time series of monthly means of Mg and Mg+ for number density as well as vertical column density in different latitudinal regions are shown. Data from the limb mesosphere-thermosphere mode of SCIAMACHY/Envisat are used, which covers the 50 km to 150 km altitude region with a vertical sampling of 3.3 km and a highest latitude of 82 deg. The high latitudes are not covered in the winter months, because there is no dayglow emission during polar night. The measurements were performed every 14 days from mid-2008 until April 2012. Mg profiles show a peak at around 90 km altitude with a density between 750 cm(exp-3) and 2000 cm(exp-3). Mg does not show strong seasonal variation at mid-latitudes. The Mg+ peak occurs 5-15 km above the neutral Mg peak at 95-105 km. Furthermore, the ions show a significant seasonal cycle with a summer maximum in both hemispheres at mid- and high-latitudes. The strongest seasonal variations of the ions are observed at mid-latitudes between 20-40 deg and densities at the peak altitude range from 500 cm(exp-3) to 6000 cm(exp-3). The peak altitude of the ions shows a latitudinal dependence with a maximum at mid-latitudes that is up to 10 km higher than the peak altitude at the equator. The SCIAMACHY measurements are compared to other measurements and WACCM model results. In contrast to the SCIAMACHY results, the WACCM results show a strong seasonal variability for Mg with a winter maximum, which is not observable by SCIAMACHY, and globally higher peak densities. Although the peak densities do not agree the vertical column densities agree, since SCIAMACHY results show a wider vertical profile. The agreement of SCIAMACHY and WACCM results is much better for Mg+, showing the same seasonality and similar peak densities. However

  19. Variations in creep rate along the Hayward Fault, California, interpreted as changes in depth of creep

    USGS Publications Warehouse

    Simpson, R.W.; Lienkaemper, J.J.; Galehouse, J.S.

    2001-01-01

    Variations ill surface creep rate along the Hayward fault are modeled as changes in locking depth using 3D boundary elements. Model creep is driven by screw dislocations at 12 km depth under the Hayward and other regional faults. Inferred depth to locking varies along strike from 4-12 km. (12 km implies no locking.) Our models require locked patches under the central Hayward fault, consistent with a M6.8 earthquake in 1868, but the geometry and extent of locking under the north and south ends depend critically on assumptions regarding continuity and creep behavior of the fault at its ends. For the northern onshore part of the fault, our models contain 1.4-1.7 times more stored moment than the model of Bu??rgmann et al. [2000]; 45-57% of this stored moment resides in creeping areas. It is important for seismic hazard estimation to know how much of this moment is released coseismically or as aseismic afterslip.

  20. Measurement of aerosol optical depth and sub-visual cloud detection using the optical depth sensor (ODS)

    NASA Astrophysics Data System (ADS)

    Toledo, D.; Rannou, P.; Pommereau, J.-P.; Sarkissian, A.; Foujols, T.

    2015-09-01

    A small and sophisticated optical depth sensor (ODS) has been designed to work in the atmosphere of Earth and Mars. The instrument measures alternatively the diffuse radiation from the sky and the attenuated direct radiation from the sun on the surface. The principal goals of ODS are to retrieve the daily mean aerosol optical depth (AOD) and to detect very high and optically thin clouds, crucial parameters in understanding the Martian and Earth meteorology and climatology. The detection of clouds is undertaken at twilight, allowing the detection and characterization of clouds with opacities below 0.03 (sub-visual clouds). In addition, ODS is capable to retrieve the aerosol optical depth during night-time from moonlight measurements. In order to study the performance of ODS under Mars-like conditions as well as to evaluate the retrieval algorithms for terrestrial measurements, ODS was deployed in Ouagadougou (Africa) between November 2004 and October 2005, a sahelian region characterized by its high dust aerosol load and the frequent occurrence of Saharan dust storms. The daily average AOD values retrieved by ODS were compared with those provided by a CIMEL Sun-photometer of the AERONET (Aerosol Robotic NETwork) network localized at the same location. Results represent a good agreement between both ground-based instruments, with a correlation coefficient of 0.79 for the whole data set and 0.96 considering only the cloud-free days. From the whole dataset, a total of 71 sub-visual cirrus (SVC) were detected at twilight with opacities as thin as 1.10-3 and with a maximum of occurrence at altitudes between 14 and 20 km. Although further analysis and comparisons are required, results indicate the potential of ODS measurements to detect sub-visual clouds.

  1. Measurement of aerosol optical depth and sub-visual cloud detection using the optical depth sensor (ODS)

    NASA Astrophysics Data System (ADS)

    Toledo, D.; Rannou, P.; Pommereau, J.-P.; Sarkissian, A.; Foujols, T.

    2016-02-01

    A small and sophisticated optical depth sensor (ODS) has been designed to work in the atmosphere of Mars. The instrument measures alternatively the diffuse radiation from the sky and the attenuated direct radiation from the Sun on the surface. The principal goals of ODS are to retrieve the daily mean aerosol optical depth (AOD) and to detect very high and optically thin clouds, crucial parameters in understanding the Martian meteorology and climatology. The detection of clouds is undertaken at twilight, allowing the detection and characterization of clouds with opacities below 0.03 (sub-visual clouds). In addition, ODS is capable to retrieve the aerosol optical depth during nighttime from moonlight measurements. Recently, ODS has been selected at the METEO meteorological station on board the ExoMars 2018 Lander. In order to study the performance of ODS under Mars-like conditions as well as to evaluate the retrieval algorithms for terrestrial measurements, ODS was deployed in Ouagadougou (Africa) between November 2004 and October 2005, a Sahelian region characterized by its high dust aerosol load and the frequent occurrence of Saharan dust storms. The daily average AOD values retrieved by ODS were compared with those provided by a CIMEL sunphotometer of the AERONET (Aerosol Robotic NETwork) network localized at the same location. Results represent a good agreement between both ground-based instruments, with a correlation coefficient of 0.77 for the whole data set and 0.94 considering only the cloud-free days. From the whole data set, a total of 71 sub-visual cirrus (SVC) were detected at twilight with opacities as thin as 1.10-3 and with a maximum of occurrence at altitudes between 14 and 20 km. Although further optimizations and comparisons of ODS terrestrial measurements are required, results indicate the potential of these measurements to retrieve the AOD and detect sub-visual clouds.

  2. Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications

    NASA Astrophysics Data System (ADS)

    Li, Chun-Feng; Shi, Xiaobin; Zhou, Zuyi; Li, Jiabiao; Geng, Jianhua; Chen, Bing

    2010-09-01

    The depths to the magnetic layer bottom (Zb) in the South China Sea (SCS) area are estimated by computing radially averaged amplitude spectra of total field magnetic anomalies. We test different sizes of moving windows in which the spectra are calculated to better understand how window sizes affect the depth estimations. Apart from lowering the resolutions of estimated Zb, larger windows do not necessarily incur presumable increases in Zb in the SCS area. Although the centroid method is taken as our primary technique for estimating Zb, for cross check, the spectral peak and the non-linear inversion methods are also applied to those windows where spectral peaks do appear. In a single window we may find discrepancy in Zb estimated from different techniques, but for all windows showing spectral peaks, the estimated Zb from one technique are grossly correlated with those from another. Our results show that most parts of the central SCS ocean basin and the northern continent-ocean transition (COT) zone have significantly smaller Zb than the surrounding continental blocks. In the surrounding continental regions Zb are averaged at about 34 km, a depth close to the Moho depth. The average Zb is about 22 km in the central basin, but this value is much larger than the Moho depth, signifying that the uppermost 10 km or so of the mantle beneath the central basin is also magnetized. The strong faulting and recent magmatism within the COT zone can account for the small Zb near the northern continental margin. The estimated Zb are also found very correlative to surface heat flow. This observation verifies dominant contributions to surface heat flow from incoming mantle heat flow due to thermal conduction. The positive correlations observed among Zb from different techniques as well as the good correlation between surface heat flow and Zb support the reasoning that our estimated Zb are within an acceptable range of accuracy.

  3. A 7-km Non-Hydrostatic Global Mesoscale Simulation with the Goddard Earth Observing System Model (GEOS-5) for Observing System Simulation Experiments

    NASA Astrophysics Data System (ADS)

    Putman, W.; Suarez, M.; Gelaro, R.; daSilva, A.; Molod, A.; Ott, L. E.; Darmenov, A.

    2014-12-01

    The Global Modeling and Assimilation Office at NASA Goddard Space Flight Center has used the Goddard Earth Observing System model (GEOS-5) to produce a 2-year non-hydrostatic global mesoscale simulation for the period of June 2005-2007. This 7-km GEOS-5 Nature Run (7km-G5NR) product will provide synthetic observations for observing system simulation experiments (OSSE)s at NASA and NOAA through the Joint Center for Satellite Data Assimilation and the NASA Center for Climate Simulation. While GEOS-5 is regularly applied in seasonal-to-decadal climate simulations, and medium range weather prediction and data assimilation, GEOS-5 is also readily adaptable for application as a global mesoscale model in pursuit of global cloud resolving applications. Recent computing advances have permitted experimentation with global atmospheric models at these scales, although production applications like the 7km-G5NR have remained limited. By incorporating a non-hydrostatic finite-volume dynamical core with scale aware physics parameterizations, the 7km-G5NR produces organized convective systems and robust weather systems ideal for producing observations for existing and new remote sensing instruments. In addition to standard meteorological parameters, the 7km-G5NR includes 15 aerosol tracers (including dust, seasalt, sulfate, black and organic carbon), O3, CO and CO2. The 7km-G5NR is driven by prescribed sea-surface temperatures and sea-ice, daily volcanic and biomass burning emissions, as well as high-resolution inventories of anthropogenic sources. We will discuss the technical challenges of producing the 7km-G5NR including the nearly 5 petabytes of full resolution output at 30-minute intervals as required by the OSSE developers, and modifications to the standard GEOS-5 physics to permit convective organization at the 'grey-zone' resolution of 7km. Highlights of the 7km-G5NR validation will focus on the representation of clouds and organized convection including tropical cyclones

  4. Marshall Space Flight Center Propulsion Systems Department (PSD) Knowledge Management (KM) Initiative

    NASA Technical Reports Server (NTRS)

    Caraccioli, Paul; Varnedoe, Tom; Smith, Randy; McCarter, Mike; Wilson, Barry; Porter, Richard

    2006-01-01

    NASA Marshall Space Flight Center's Propulsion Systems Department (PSD) is four months into a fifteen month Knowledge Management (KM) initiative to support enhanced engineering decision making and analyses, faster resolution of anomalies (near-term) and effective, efficient knowledge infused engineering processes, reduced knowledge attrition, and reduced anomaly occurrences (long-term). The near-term objective of this initiative is developing a KM Pilot project, within the context of a 3-5 year KM strategy, to introduce and evaluate the use of KM within PSD. An internal NASA/MSFC PSD KM team was established early in project formulation to maintain a practitioner, user-centric focus throughout the conceptual development, planning and deployment of KM technologies and capabilities within the PSD. The PSD internal team is supported by the University of Alabama's Aging Infrastructure Systems Center of Excellence (AISCE), lntergraph Corporation, and The Knowledge Institute. The principle product of the initial four month effort has been strategic planning of PSD KNI implementation by first determining the "as is" state of KM capabilities and developing, planning and documenting the roadmap to achieve the desired "to be" state. Activities undertaken to suppoth e planning phase have included data gathering; cultural surveys, group work-sessions, interviews, documentation review, and independent research. Assessments and analyses have beon pedormed including industry benchmarking, related local and Agency initiatives, specific tools and techniques used and strategies for leveraging existing resources, people and technology to achieve common KM goals. Key findings captured in the PSD KM Strategic Plan include the system vision, purpose, stakeholders, prioritized strategic objectives mapped to the top ten practitioner needs and analysis of current resource usage. Opportunities identified from research, analyses, cultural1KM surveys and practitioner interviews include

  5. Trimethylamine oxide, betaine and other osmolytes in deep-sea animals: depth trends and effects on enzymes under hydrostatic pressure.

    PubMed

    Yancey, P H; Rhea, M D; Kemp, K M; Bailey, D M

    2004-06-01

    Most shallow teleosts have low organic osmolyte contents, e.g. 70 mmol/kg or less of trimethylamine oxide (TMAO). Our previous work showed that TMAO contents increase with depth in muscles of several Pacific families of teleost fishes, to about 180 mmol/kg wet wt at 2.9 km depth in grenadiers. We now report that abyssal grenadiers (Coryphaenoides armatus, Macrouridae) from the Atlantic at 4.8 km depth contain 261 mmol/kg wet wt in muscle tissue. This precisely fits a linear trend extrapolated from the earlier data. We also found that anemones show a trend of increasing contents of methylamines (TMAO, betaine) and scyllo-inositol with increasing depth. Previously we found that TMAO counteracts the inhibitory effects of hydrostatic pressure on a variety of proteins. We now report that TMAO and, to a lesser extent, betaine, are generally better stabilizers than other common osmolytes (myo-inositol, taurine and glycine), in terms of counteracting the effects of pressure on NADH Km of grenadier lactate dehydrogenase and ADP Km of anemone and rabbit pyruvate kinase. PMID:15529747

  6. Real-time structured light depth extraction

    NASA Astrophysics Data System (ADS)

    Keller, Kurtis; Ackerman, Jeremy D.

    2000-03-01

    Gathering depth data using structured light has been a procedure for many different environments and uses. Many of these system are utilized instead of laser line scanning because of their quickness. However, to utilize depth extraction for some applications, in our case laparoscopic surgery, the depth extraction must be in real time. We have developed an apparatus that speeds up the raw image display and grabbing in structured light depth extraction from 30 frames per second to 60 and 180 frames per second. This results in an updated depth and texture map of about 15 times per second versus about 3. This increased update rate allows for real time depth extraction for use in augmented medical/surgical applications. Our miniature, fist-sized projector utilizes an internal ferro-reflective LCD display that is illuminated with cold light from a flex light pipe. The miniature projector, attachable to a laparoscope, displays inverted pairs of structured light into the body where these images are then viewed by a high-speed camera set slightly off axis from the projector that grabs images synchronously. The images from the camera are ported to a graphics-processing card where six frames are worked on simultaneously to extract depth and create mapped textures from these images. This information is then sent to the host computer with 3D coordinate information of the projector/camera and the associated textures. The surgeon is then able to view body images in real time from different locations without physically moving the laparoscope imager/projector, thereby, reducing the trauma of moving laparoscopes in the patient.

  7. Compilation of known and suspected Quaternary faults within 100 km of Yucca Mountain, Nevada and California

    SciTech Connect

    Piety, L.A.

    1996-12-31

    Geologic data have been compiled for known and suspected Quaternary faults in southern Nevada and southeastern California within about 100 km of the potential repository site at Yucca Mountain. The data set includes regional studies that attempt to identify and evaluate lineaments, scraps, and other possible tectonic landforms of possible Quaternary age, detailed studies that focus on a single fault, and geologic studies that were completed for purposes other than evaluation of Quaternary fault activity. Studies included in this compilation are those that were available as of December 1993. Faults that have known or suspected Quaternary activity are presented on a topographic base map at a scale of 1:250,000. Data for each fault that are pertinent to the assessment of future faulting and earthquake events are assembled on description sheets and summarized on tables. This compilation identifies ten faults within 50 km of the site but outside the site area and an additional fourteen faults between 50 km and 100 km of the site for which evidence for Holocene or late Pleistocene surface rupture has been reported in the literature. The longest and most continuous of these faults is the northwest-striking, 250-km-long Furnace Creek fault (including its possible extension into Fish Lake Valley), which is located about 50 km west of the site. In addition to identifying known or suspected Quaternary faults within about 100 km of the site, this compilation demonstrates the lack of information for most of these faults.

  8. Atlas of depth-duration frequency of precipitation annual maxima for Texas

    USGS Publications Warehouse

    Asquith, William H.; Roussel, Meghan C.

    2004-01-01

    Ninety-six maps depicting the spatial variation of the depth-duration frequency of precipitation annual maxima for Texas are presented. The recurrence intervals represented are 2, 5, 10, 25, 50, 100, 250, and 500 years. The storm durations represented are 15 and 30 minutes; 1, 2, 3, 6, and 12 hours; and 1, 2, 3, 5, and 7 days. The maps were derived using geographically referenced parameter maps of probability distributions used in previously published research by the U.S. Geological Survey to model the magnitude and frequency of precipitation annual maxima for Texas. The maps in this report apply that research and update depth-duration frequency of precipitation maps available in earlier studies done by the National Weather Service.

  9. Atlas of depth-duration frequency of precipitation annual maxima for Texas

    USGS Publications Warehouse

    Asquith, William H.; Roussel, Meghan C.

    2004-01-01

    The objective of this Texas Department of Transportation (TxDOT) and U.S. Geological Survey (USGS) cooperatively funded project was to develop a simple-to-use atlas of precipitation depths in Texas for selected storm durations and frequencies on the basis of the research results and unpublished digital archives of Asquith (1998). The selected storm durations are 15 and 30 minutes; 1, 2, 3, 6, and 12 hours; and 1, 2, 3, 5, and 7 days. The selected storm frequencies or annual recurrence intervals are 2, 5, 10, 25, 50, 100, 250, and 500 years. Depth-duration frequency (DDF) of annual precipitation maxima is important for cost-effective, riskmitigated hydrologic design. DDF values are in common and wide-spread use by public and private entities throughout Texas.

  10. Comparative genomic analysis of the swine pathogen Bordetella bronchisepticastrain KM22.

    PubMed

    Nicholson, Tracy L; Shore, Sarah M; Register, Karen B; Bayles, Darrell O; Kingsley, Robert A; Brunelle, Brain W

    2016-01-15

    The well-characterized Bordetella bronchiseptica strain KM22, originally isolated from a pig with atrophic rhinitis, has been used to develop a reproducible swine respiratory disease model. The goal of this study was to identify genetic features unique to KM22 by comparing the genome sequence of KM22 to the laboratory reference strain RB50. To gain a broader perspective of the genetic relationship of KM22 among other B. bronchiseptica strains, selected genes of KM22 were then compared to five other B. bronchiseptica strains isolated from different hosts. Overall, the KM22 genome sequence is more similar to the genome sequences of the strains isolated from animals than the strains isolated from humans. The majority of virulence gene expression in Bordetella is positively regulated by the two-component sensory transduction system BvgAS. bopN, bvgA, fimB, and fimC were the most highly conserved BvgAS-regulated genes present in all seven strains analyzed. In contrast, the BvgAS-regulated genes present in all seven strains with the highest sequence divergence werefimN, fim2, fhaL, andfhaS. A total of eight major fimbrial subunit genes were identified in KM22. Quantitative real-time PCR data demonstrated that seven of the eight fimbrial subunit genes identified in KM22 are expressed and regulated by BvgAS. The annotation of the KM22 genome sequence, coupled with the comparative genomic analyses reported in this study, can be used to facilitate the development of vaccines with improved efficacy towards B. bronchiseptica in swine to decrease the prevalence and disease burden caused by this pathogen. PMID:26711033

  11. Comparative genomic analysis of the swine pathogen Bordetella bronchisepticastrain KM22.

    PubMed

    Nicholson, Tracy L; Shore, Sarah M; Register, Karen B; Bayles, Darrell O; Kingsley, Robert A; Brunelle, Brain W

    2016-01-01

    The well-characterized Bordetella bronchiseptica strain KM22, originally isolated from a pig with atrophic rhinitis, has been used to develop a reproducible swine respiratory disease model. The goal of this study was to identify genetic features unique to KM22 by comparing the genome sequence of KM22 to the laboratory reference strain RB50. To gain a broader perspective of the genetic relationship of KM22 among other B. bronchiseptica strains, selected genes of KM22 were then compared to five other B. bronchiseptica strains isolated from different hosts. Overall, the KM22 genome sequence is more similar to the genome sequences of the strains isolated from animals than the strains isolated from humans. The majority of virulence gene expression in Bordetella is positively regulated by the two-component sensory transduction system BvgAS. bopN, bvgA, fimB, and fimC were the most highly conserved BvgAS-regulated genes present in all seven strains analyzed. In contrast, the BvgAS-regulated genes present in all seven strains with the highest sequence divergence werefimN, fim2, fhaL, andfhaS. A total of eight major fimbrial subunit genes were identified in KM22. Quantitative real-time PCR data demonstrated that seven of the eight fimbrial subunit genes identified in KM22 are expressed and regulated by BvgAS. The annotation of the KM22 genome sequence, coupled with the comparative genomic analyses reported in this study, can be used to facilitate the development of vaccines with improved efficacy towards B. bronchiseptica in swine to decrease the prevalence and disease burden caused by this pathogen.

  12. Digital data sets of depth-duration frequency of precipitation for Oklahoma

    USGS Publications Warehouse

    Rea, Alan; Tortorelli, Robert L.

    1999-01-01

    These geospatial data sets were produced as part of a regional precipitation frequency analysis for Oklahoma. The data sets consist of surface grids of precipitation depths for seven frequencies (expressed as recurrence intervals of 2-, 5-, 10-, 25-, 50-, 100-, and 500-years) and 12 durations (15-, 30-, and 60-minutes; 1-, 2-, 3-, 6-, 12-, and 24-hours; and 1-, 3-, and 7-days). Eighty-four depth-duration-frequency surfaces were produced from precipitation-station data. Precipitation-station data from which the surfaces were interpolated and contour lines derived from each surface also are included. Contour intervals vary from 0.05 to 0.5 inch. Data were used from precipitation gage stations with at least 10 years of record within Oklahoma and a zone extending about 50 kilometers into bordering states. Three different rain gage networks provided the data (15-minute, 1-hour, and 1-day). Precipitation annual maxima (depths) were determined from the station data for each duration for 110 15-minute, 141 hourly, and 413 daily stations. Statistical methods were used to estimate precipitation depths for each duration-frequency at each station. These station depth-duration-frequency estimates were interpolated to produce continuous grids with grid-cell spacing of 2,000 meters. Contour lines derived from these surfaces (grids) were used to produce the maps in the 'Depth-Duration Frequency of Precipitation for Oklahoma,' by R.L. Tortorelli, Alan Rea, and W.H. Asquith, U.S. Geological Survey Water-Resources Investigations Report 99-4232. The geospatial data sets are presented in digital form for use with geographic information systems. These geospatial data sets may be used to determine an interpolated value of depth-duration-frequency of precipitation for any point in Oklahoma.

  13. Moho depth and crustal structure of the Siberian Craton and the West Siberian Basin: An appraisal of existing seismic data

    NASA Astrophysics Data System (ADS)

    Cherepanova, Yulia; Artemieva, Irina M.; Thybo, Hans

    2013-04-01

    We present a digital model of the crustal structure of the Archean-Proterozoic Siberian craton and the Paleozoic-Mesozoic West Siberian basin, based on seismic profiles published since 1960 in international and Russian journals, books, theses and reports. Data quality was assessed and quantitatively assigned to each profile based on acquisition and interpretation method and completeness of the model. The database represents major improvement in coverage and resolution with a nominal sample interval of 50 km before interpolation onto a uniform grid. It includes depth to Moho, thickness and average P-wave velocity of five crustal layers (sediments, and upper, middle, lower, and lowermost crust) and Pn velocity. Results are presented in maps and cross-sections, which demonstrate strong crustal heterogeneity. Crustal structure shows weak correlation with tectono-thermal age and strong correlation with tectonic setting. Sedimentary thickness varies from 0-3 km in stable craton to 10-20 km in extended regions. Typical Moho depths are 44-46 km in stable Archean crust, 40-42 km in Proterozoic craton and Neoproterozoic/Paleozoic orogens, 35-38 km in extended cratonic crust, and 38-40 km in the West Siberian basin. Average crustal velocity is ~6.2-6.4 km/s, ranging from <5.8 km/s in deep sedimentary basins to ~6.6 km/s around the up-to 54 km thick Anabar shield crust. The cratonic crust generally consists of three layers and has no high-velocity lowermost crust (Vp~7.4 km/s), which is observed only in magmatic areas. Upper mantle Pn velocities are generally ~8.2 km/s in the craton and West Siberian Basin, lower in Baikalian and Caledonian areas, higher in the Tunguska and Viluy basins, and abnormally high (8.6-8.9 km/s) around kimberlite fields. We provide an extensive summary of the tectonic and geodynamic evolution of the region and discuss the origin of crustal heterogeneity and processes of crustal evolution in Precambrian cratons and major Phanerozoic basins and rift

  14. Modern Foraminifera from a depth transect offshore Brunei Darussalam: diversity, sedimentation rate and preservation pathways.

    NASA Astrophysics Data System (ADS)

    Briguglio, Antonino; Goeting, Sulia; Kusli, Rosnani; Roslim, Amajida; Polgar, Gianluca; Kocsis, Laszlo

    2016-04-01

    For this study, 11 samples have been collected by scuba diving from 5 to 35 meters water depth off shore Brunei Darussalam. The locations sampled are known as: Pelong Rock (5 samples, shallow reef with soft and stony corals and larger foraminifera, 5 to 8 meters water depth), Abana Rock (1 sample, shallow reef with mainly soft corals and larger foraminifera, 13 to 18 meters water depth), Oil Rig wreck (1 sample, very sandy bottom with larger foraminifera, 18 meters water depth), Dolphin wreck (1 sample, muddy sand with many small rotaliids, 24 meters water depth), US wreck, (1 sample, sand with small clay fraction, 28 meters water depth), Australian wreck (1 sample, mainly medium to coarse sand with larger foraminifera, 34 meters water depth) and Blue water wreck (1 sample, mainly coarse sand, coral rubble and larger foraminifera, 35 meters water depth). Those samples closer to the river inputs are normally richer in clay, while the most distant samples are purely sandy. Some additional samples have been collected next to reef environments which, even if very shallow, are mainly sandy with almost no clay fraction. The deepest sample, which is 30 km offshore, contains some planktonic foraminifera and is characterized by a large range of preservations concerning foraminifera, thus testifying the presence or relict sediments at the sea bottom. The presence of relict sediments was already pointed out by older oil-related field studies offshore Brunei Darussalam, and now it is possible to draw the depth limit of these deposits. The diversity of the benthic foraminiferal fauna is relatively high but not as higher as neighboring regions as some studies have highlighted. The species collected and identified are more than 50: in reef environment the most abundant are Calcarina defrancii, Neorotalia calcar and the amphisteginidae; deeper in the muddy sediments the most abundant is Pararotalia schroeteriana and in the deepest sandy sample the most abundant are Calcarina

  15. Dosimetry of secondary cosmic radiation up to an altitude of 30 km.

    PubMed

    Wissmann, F; Burda, O; Khurana, S; Klages, T; Langner, F

    2014-10-01

    Dosimetric measurements in the field of secondary cosmic radiation were extensively made during the last years. Since the majority of these measurements were performed on-board passenger aircraft at altitudes between 10 and 12 km, measurements at higher altitudes are desirable for the verification of the legal dose assessment procedures for aircrew. A simple solution is to use a high-altitude balloon that reaches altitudes as high as 30 km. In this work, it is shown that the dose rate profile up to 30 km can be measured with acceptable uncertainties using a Si-detector. PMID:24345463

  16. Dosimetry of secondary cosmic radiation up to an altitude of 30 km.

    PubMed

    Wissmann, F; Burda, O; Khurana, S; Klages, T; Langner, F

    2014-10-01

    Dosimetric measurements in the field of secondary cosmic radiation were extensively made during the last years. Since the majority of these measurements were performed on-board passenger aircraft at altitudes between 10 and 12 km, measurements at higher altitudes are desirable for the verification of the legal dose assessment procedures for aircrew. A simple solution is to use a high-altitude balloon that reaches altitudes as high as 30 km. In this work, it is shown that the dose rate profile up to 30 km can be measured with acceptable uncertainties using a Si-detector.

  17. Characterization of the KM3NeT photomultipliers in the Hellenic Open University

    SciTech Connect

    Bourlis, G.; Avgitas, T.; Tsirigotis, A.; Tzamarias, S.; Collaboration: KM3NeT Collaboration

    2014-11-18

    The KM3NeT neutrino research infrastructure will be a deep sea multidisciplinary observatory in the Mediterranean Sea hosting a neutrino telescope. The Physics Laboratory of the Hellenic Open University is involved in the characterization of the KM3NeT neutrino detector. The present work describes measurement techniques for the functional characteristics of the candidate KM3NeT photomultipliers. These characteristics include dark current, transit time spread, gain slope and single photoelectron characteristics, as well as delayed and after pulses.

  18. Effects of dietary glycerin inclusion at 0, 5, 10, and 15 percent of dry matter on energy metabolism and nutrient balance in finishing beef steers.

    PubMed

    Hales, K E; Foote, A P; Brown-Brandl, T M; Freetly, H C

    2015-01-01

    Expansion of the biodiesel industry has increased the glycerin (GLY) supply. Glycerin is an energy-dense feed that can be used in ruminant species; however, the energy value of GLY is not known. Therefore, the effects of GLY inclusion at 0, 5, 10, and 15% on energy balance in finishing cattle diets were evaluated in 8 steers (BW = 503 kg) using a replicated Latin square design. Data were analyzed with the fixed effects of dietary treatment and period, and the random effects of square and steer within square were included in the model. Contrast statements were used to separate linear and quadratic effects of GLY inclusion. Glycerin replaced dry-rolled corn (DRC) at 0, 5, 10, and 15% of dietary DM. Dry matter intake decreased linearly (P = 0.02) as GLY increased in the diet. As a proportion of GE intake, fecal energy loss tended to decrease linearly (P < 0.07), and DE also tended to increase linearly (P = 0.07) as dietary level of GLY increased. Urinary energy loss was not different (P > 0.31) as a proportion of GE as GLY increased in the diet. Methane energy loss as a proportion of GE intake tended to respond quadratically (P = 0.10), decreasing from 0 to 10% GLY inclusion and increasing thereafter. As a proportion of GE intake, ME tended to respond quadratically (P = 0.10), increasing from 0 to 10% GLY and then decreasing. As a proportion of GE intake, heat production increased linearly (P = 0.02) as GLY increased in the diet. Additionally, as a proportion of GE intake, retained energy (RE) tended to respond quadratically (P = 0.07), increasing from 0 to 10% GLY inclusion and decreasing thereafter. As a proportion of N intake, urinary and fecal N excretion increased linearly (P < 0.04) as GLY increased in the diet. Furthermore, grams of N retained and N retained as a percent of N intake both decreased linearly (P < 0.02) as GLY increased in the diet. Total DM digestibility tended (P < 0.10) to respond quadratically, increasing at a decreasing rate from 0 to 5% GLY

  19. TRENDS IN ESTIMATED MIXING DEPTH DAILY MAXIMUMS

    SciTech Connect

    Buckley, R; Amy DuPont, A; Robert Kurzeja, R; Matt Parker, M

    2007-11-12

    Mixing depth is an important quantity in the determination of air pollution concentrations. Fireweather forecasts depend strongly on estimates of the mixing depth as a means of determining the altitude and dilution (ventilation rates) of smoke plumes. The Savannah River United States Forest Service (USFS) routinely conducts prescribed fires at the Savannah River Site (SRS), a heavily wooded Department of Energy (DOE) facility located in southwest South Carolina. For many years, the Savannah River National Laboratory (SRNL) has provided forecasts of weather conditions in support of the fire program, including an estimated mixing depth using potential temperature and turbulence change with height at a given location. This paper examines trends in the average estimated mixing depth daily maximum at the SRS over an extended period of time (4.75 years) derived from numerical atmospheric simulations using two versions of the Regional Atmospheric Modeling System (RAMS). This allows for differences to be seen between the model versions, as well as trends on a multi-year time frame. In addition, comparisons of predicted mixing depth for individual days in which special balloon soundings were released are also discussed.

  20. Binocular coordination: reading stereoscopic sentences in depth.

    PubMed

    Schotter, Elizabeth R; Blythe, Hazel I; Kirkby, Julie A; Rayner, Keith; Holliman, Nicolas S; Liversedge, Simon P

    2012-01-01

    The present study employs a stereoscopic manipulation to present sentences in three dimensions to subjects as they read for comprehension. Subjects read sentences with (a) no depth cues, (b) a monocular depth cue that implied the sentence loomed out of the screen (i.e., increasing retinal size), (c) congruent monocular and binocular (retinal disparity) depth cues (i.e., both implied the sentence loomed out of the screen) and (d) incongruent monocular and binocular depth cues (i.e., the monocular cue implied the sentence loomed out of the screen and the binocular cue implied it receded behind the screen). Reading efficiency was mostly unaffected, suggesting that reading in three dimensions is similar to reading in two dimensions. Importantly, fixation disparity was driven by retinal disparity; fixations were significantly more crossed as readers progressed through the sentence in the congruent condition and significantly more uncrossed in the incongruent condition. We conclude that disparity depth cues are used on-line to drive binocular coordination during reading.

  1. a Borehole Seismic System for Active and Passive Seimsic Studies to 3 KM at Ptrc's Aquistore Project

    NASA Astrophysics Data System (ADS)

    Schmitt, D. R.; Nixon, C.; Kofman, R.; White, D. J.; Worth, K.

    2015-12-01

    We have constructed a downhole seismic recording system for application to depths of nearly 3 km and temperatures up to 135 °C at Aquistore, an independent research and monitoring project in which liquid CO2 is being stored in a brine and sandstone water formation. The key component to this system is a set of commercially available slim-hole 3-C sondes carrying 15 Hz geophones deployable in open and cased boreholes with diameters as small as 57 mm. The system is currently hosted on a 4-conductor wireline with digital information streamed to the surface recording unit. We have further incorporated these sondes into a mobile passive monitoring unit that includes a number of redundancies such as a multiple Tbyte network accessible RAID hard-drive system (NAS) and a self-designed uninterruptible power supply. The system can be remotely controlled via the internet. The system is currently deployed covering a range of depths from 2850 m to 2910 m. Ambient temperatures at this depth are approximately 110 °C with onboard tool temperatures running at 115 °C. Data is continuously streamed to the NAS for archiving, approximately 11 GBytes of data is recorded per day at the sampling period of 0.5 ms. The lack of noise at this depth allows short data snippets to be flagged with a simple amplitude threshold criteria. The greatly reduced data volume of the snippets allows for ready access via the internet to the system for ongoing quality control. Spurious events, mostly small amplitude tube waves originating at or near the surface, are readily discounted. Active seismic measurements are carried out simultaneously but these require that an appropriately accurate independent GPS based time synchronization be used. Various experiences with event detection, orientation of sondes using both explosives and seismic vibrator, potential overheating of the surface electronics, and issues related to loss of shore power provide for a detailed case study. Aquistore, managed by the

  2. Capture and sequestration of CO2 in the interlayer space of hydrated calcium Montmorillonite clay under various geological burial depth

    NASA Astrophysics Data System (ADS)

    Yang, W.; Zaoui, A.

    2016-05-01

    We perform, at nanoscale level, the structure and dynamics of carbon dioxide molecules in hydrated Ca-montmorillonite clays. The swelling behaviour of hydrated Wyoming-type Montmorillonite including CO2 molecules and counterions is presented and analysed. In addition, the atom density profile, diffusion behaviours and radial distribution functions of CO2, interlayer water molecules and Calcium ions have been investigated at different geological burial depth of 0 km, 3 km and 6 km, which correspond to various temperature and pressure of simulation conditions. Furthermore, the influence of different hydration state on the dynamical behaviours of carbon dioxide is also explained. The calculated self-diffusion coefficient shows that the carbon dioxide species diffuse more freely with the increase of depth and water content. We also found that the presence of interlayer CO2 inhibits the diffusion of all the mobile species. These results mainly show that the hydrated clay system is an appropriate space capable of absorbing CO2 molecules.

  3. Modeling and detection of regional depth phases at the GERES array

    NASA Astrophysics Data System (ADS)

    Apoloner, M.-T.; Bokelmann, G.

    2015-08-01

    The Vienna Basin in Eastern Austria is a region of low to moderate seismicity, and hence the seismological network coverage is relatively sparse. Nevertheless, the area is one of the most densely populated and most developed areas in Austria, so accurate earthquake location, including depth estimation and relation to faults is not only important for understanding tectonic processes, but also for estimating seismic hazard. Particularly depth estimation needs a dense seismic network around the anticipated epicenter. If the station coverage is not sufficient, the depth can only be estimated roughly. Regional Depth Phases (RDP) like sPg, sPmP and sPn have been already used successfully for calculating depth even if only observable from one station. However, especially in regions with sedimentary basins these phases prove difficult or impossible to recover from the seismic records. For this study we use seismic array data from GERES. It is 220 km to the North West of the Vienna Basin, which - according to literature - is a suitable distance to recover PmP and sPmP phases. We use array processing on recent earthquake data from the Vienna Basin with local magnitudes from 2.1 to 4.2 to reduce the SNR and to search for RDP. At the same time, we do similar processing on synthetic data specially modeled for this application. We compare real and synthetic results to assess which phases can be identified and to what extent depth estimation can be improved. Additionally, we calculate a map of lateral propagation behavior of RDP for a typical strike-slip earthquake in our region of interest up to 400 km distance. For our study case RDP propagation is strongly azimuthally dependent. Also, distance ranges differ from literature sources. Comparing with synthetic seismograms we identify PmP and PbP phases with array processing as strongest arrivals. Although the associated depth phases cannot be identified at this distance and azimuth, identification of the PbP phases limits possible

  4. Non-Linearity Analysis of Depth and Angular Indexes for Optimal Stereo SLAM

    PubMed Central

    Bergasa, Luis M.; Alcantarilla, Pablo F.; Schleicher, David

    2010-01-01

    In this article, we present a real-time 6DoF egomotion estimation system for indoor environments using a wide-angle stereo camera as the only sensor. The stereo camera is carried in hand by a person walking at normal walking speeds 3–5 km/h. We present the basis for a vision-based system that would assist the navigation of the visually impaired by either providing information about their current position and orientation or guiding them to their destination through different sensing modalities. Our sensor combines two different types of feature parametrization: inverse depth and 3D in order to provide orientation and depth information at the same time. Natural landmarks are extracted from the image and are stored as 3D or inverse depth points, depending on a depth threshold. This depth threshold is used for switching between both parametrizations and it is computed by means of a non-linearity analysis of the stereo sensor. Main steps of our system approach are presented as well as an analysis about the optimal way to calculate the depth threshold. At the moment each landmark is initialized, the normal of the patch surface is computed using the information of the stereo pair. In order to improve long-term tracking, a patch warping is done considering the normal vector information. Some experimental results under indoor environments and conclusions are presented. PMID:22319348

  5. Non-linearity analysis of depth and angular indexes for optimal stereo SLAM.

    PubMed

    Bergasa, Luis M; Alcantarilla, Pablo F; Schleicher, David

    2010-01-01

    In this article, we present a real-time 6DoF egomotion estimation system for indoor environments using a wide-angle stereo camera as the only sensor. The stereo camera is carried in hand by a person walking at normal walking speeds 3-5 km/h. We present the basis for a vision-based system that would assist the navigation of the visually impaired by either providing information about their current position and orientation or guiding them to their destination through different sensing modalities. Our sensor combines two different types of feature parametrization: inverse depth and 3D in order to provide orientation and depth information at the same time. Natural landmarks are extracted from the image and are stored as 3D or inverse depth points, depending on a depth threshold. This depth threshold is used for switching between both parametrizations and it is computed by means of a non-linearity analysis of the stereo sensor. Main steps of our system approach are presented as well as an analysis about the optimal way to calculate the depth threshold. At the moment each landmark is initialized, the normal of the patch surface is computed using the information of the stereo pair. In order to improve long-term tracking, a patch warping is done considering the normal vector information. Some experimental results under indoor environments and conclusions are presented.

  6. Depth migration of seasonally induced seismicity at The Geysers geothermal field

    NASA Astrophysics Data System (ADS)

    Johnson, Christopher W.; Totten, Eoghan J.; Bürgmann, Roland

    2016-06-01

    Seismicity from injected fluids provides insight into the hydraulically conductive fracture network at The Geysers (TG), California, geothermal reservoir. Induced earthquakes at TG result from both thermoelastic and poroelastic stresses as injected fluids cool the rocks and increase pore pressure. The spatiotemporal evolution of M ≥ 1.5 seismicity is characterized as a function of depth in the northwest and southeast regions of TG to develop time-dependent earthquake rates using an epidemic-type aftershock sequence model. The seismicity and injection follow an annual cycle that peaks in the winter months and is correlated by depth. The results indicate a time lag of ≤6 months for fluids to migrate >3 km below the injection depth. Water injection is the main cause of seismicity as fluids penetrate into the reservoir. Our results suggest that a steeply dipping fracture network of hydraulically conductive faults allows fluid migration to a few kilometers below the point of injection.

  7. Thermobarometry of metamorphosed pseudotachylyte and associated mylonite: Constraints on dynamic Co-seismic rupture depth attending Caledonian extension, North Norway

    NASA Astrophysics Data System (ADS)

    Leib, S. E.; Moecher, D. P.; Steltenpohl, M. G.; Andresen, Arild

    2016-07-01

    The exhumed post-Caledonian Eidsfjord and Fiskfjord extensional shear zones of northern Norway exhibit evidence of coseismic rupture propagating into the ductile crust as evidenced by the presence of mylonitic and metamorphosed pseudotachylyte. Geothermobarometric calculations on garnet-bearing mineral assemblages in mylonitic gneisses associated with mylonitic pseudotachylyte and in metamorphosed pseudotachylyte permit determination of the depth and ambient temperature of seismogenic low-angle ductile extension. Average pressures from Eidsfjord (570 ± 115 MPa at ca. 650 °C) and Fiskfjord (1120 ± 220 MPa at ca. 650 °C) correspond to faulting depths of 21 ± 4 km and 41 ± 9 km, respectively. The Fiskfjord results agree with previous thermobarometric calculations on mylonitic Cpx + Grt-bearing pseudotachylyte at Fiskfjord. The calculated depths are 5-25 km below the depth of the standard seismogenic zone. These results demonstrate that low angle normal faults may cut through a large portion of continental crust. This occurrence of mylonitic pseudotachylyte in an extensional crustal setting is most easily explained by dynamic downward rupture into the ductile regime and/or unusually high shear stresses to account for coseismic rupture at such depths, implying a direct connection with a seismogenic normal fault in the upper crust.

  8. Variability in Soil Properties at Different Spatial Scales (1 m to 1 km) in a Deciduous Forest Ecosystem

    SciTech Connect

    Garten Jr, Charles T; Kang, S.; Brice, Deanne Jane; Schadt, Christopher Warren; Zhou, Jizhong

    2007-01-01

    The purpose of this research was to test the hypothesis that variability in 11 soil properties, related to soil texture and soil C and N, would increase from small (1 m) to large (1 km) spatial scales in a temperate, mixed-hardwood forest ecosystem in east Tennessee, USA. The results were somewhat surprising and indicated that a fundamental assumption in geospatial analysis, namely that variability increases with increasing spatial scale, did not apply for at least five of the 11 soil properties measured over a 0.5-km2 area. Composite mineral soil samples (15 cm deep) were collected at 1, 5, 10, 50, 250, and 500 m distances from a center point along transects in a north, south, east, and westerly direction. A null hypothesis of equal variance at different spatial scales was rejected (P{le}0.05) for mineral soil C concentration, silt content, and the C-to-N ratios in particulate organic matter (POM), mineral-associated organic matter (MOM), and whole surface soil. Results from different tests of spatial variation, based on coefficients of variation or a Mantel test, led to similar conclusions about measurement variability and geographic distance for eight of the 11 variables examined. Measurements of mineral soil C and N concentrations, C concentrations in MOM, extractable soil NH{sub 4}-N, and clay contents were just as variable at smaller scales (1-10 m) as they were at larger scales (50-500 m). On the other hand, measurement variation in mineral soil C-to-N ratios, MOM C-to-N ratios, and the fraction of soil C in POM clearly increased from smaller to larger spatial scales. With the exception of extractable soil NH4-N, measured soil properties in the forest ecosystem could be estimated (with 95% confidence) to within 15% of their true mean with a relatively modest number of sampling points (n{le}25). For some variables, scaling up variation from smaller to larger spatial domains within the ecosystem could be relatively easy because small-scale variation may be

  9. Wide-band (2.5 - 10.5 µm), high-frame rate IRFPAs based on high-operability MCT on silicon

    NASA Astrophysics Data System (ADS)

    Crosbie, Michael J.; Giess, Jean; Gordon, Neil T.; Hall, David J.; Hails, Janet E.; Lees, David J.; Little, Christopher J.; Phillips, Tim S.

    2010-04-01

    We have previously presented results from our mercury cadmium telluride (MCT, Hg1-xCdxTe) growth on silicon substrate technology for different applications, including negative luminescence, long waveband and mid/long dual waveband infrared imaging. In this paper, we review recent developments in QinetiQ's combined molecular beam epitaxy (MBE) and metal-organic vapor phase epitaxy (MOVPE) MCT growth on silicon; including MCT defect density, uniformity and reproducibility. We also present a new small-format (128 x 128) focal plane array (FPA) for high frame-rate applications. A custom high-speed readout integrated circuit (ROIC) was developed with a large pitch and large charge storage aimed at producing a very high performance FPA (NETD ~10mK) operating at frame rates up to 2kHz for the full array. The array design allows random addressing and this allows the maximum frame rate to be increased as the window size is reduced. A broadband (2.5-10.5 μm) MCT heterostructure was designed and grown by the MBE/MOVPE technique onto silicon substrates. FPAs were fabricated using our standard techniques; wet-etched mesa diodes passivated with epitaxial CdTe and flip-chip bonded to the ROIC. The resulting focal plane arrays were characterized at the maximum frame rate and shown to have the high operabilities and low NETD values characteristic of our LWIR MCT on silicon technology.

  10. Crystal structure of 16-ferrocenylmethyl-3β-hydroxy­estra-1,3,5(10)-trien-17-one: a potential chemotherapeutic drug

    PubMed Central

    Carmona-Negrón, José A.; Flores-Rivera, Mariola M.; Díaz-Reyes, Zaibeth; Moore, Curtis E.; Rheigold, Arnold L.; Meléndez, Enrique

    2016-01-01

    A new ferrocene complex, 16-ferrocenylmethyl-3β-hy­droxy­estra-1,3,5(10)-trien-17-one dimethyl sulfoxide monosolvate, [Fe(C5H5)(C24H27O2)]·C2H6OS, has been synthesized and structurally characterized by single-crystal X-ray diffraction techniques. The mol­ecule crystallizes in the space group P21 with one mol­ecule of dimethyl sulfoxide. A hydrogen bond links the phenol group and the dimethyl sulfoxide O atom, with an O⋯O distance of 2.655 (5) Å. The ferrocene group is positioned in the β face of the estrone moiety, with an O—C—C—C torsion angle of 44.1 (5)°, and the carbonyl bond length of the hormone moiety is 1.216 (5) Å, typical of a C=O double bond. The average Fe—C bond length of the substituted Cp ring [Fe—C(Cp*)] is similar to that of the unsubstituted one [Fe—C(Cp)], i.e. 2.048 (3) versus 2.040 (12) Å. The structure of the complex is compared with those of estrone and eth­oxy­methyl­estrone. PMID:27308062

  11. Synthesis of 21,23-selenium- and tellurium-substituted 5-porphomethenes, 5,10-porphodimethenes, 5,15-porphodimethenes, and porphotrimethenes and their interactions with mercury.

    PubMed

    Ahmad, Sohail; Yadav, Kumar Karitkey; Bhattacharya, Soumee; Chauhan, Prashant; Chauhan, S M S

    2015-04-17

    The 3+1 condensation of symmetrical 16-Selena/telluratripyrranes with symmetrical selenophene-2,5-diols/tellurophene-2,5-diols in the presence of BF3-etheratre or BF3-methanol followed by oxidation with DDQ gave 5,10-porphodimethenes, whereas the process with unsymmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave 5-porphomethenes. In addition, the reaction of unsymmetrical 16-Selena/telluratripyrranes with symmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave the corresponding porphotrimethenes, whereas the process with unsymmetrical selenophene-2,5-diols/tellurophene-2,5-diols gave the 5,15-porphodimethenes. The structures of different products were characterized by IR, (1)H and (13)C NMR, (1)H-(1)H COSY, CHN analysis, and mass spectrometry. The binding of mercury with the calix[4]phyrins mentioned above had been observed in the decreasing order of porphodimethenes > porphomethenes > porphotrimethenes by UV-vis and (1)H NMR spectroscopy.

  12. Solvent effects on spectrophotometric titrations and vibrational spectroscopy of 5,10,15-triphenyl-20-(4-hydroxyphenyl)porphyrin in aqueous DMF.

    PubMed

    Guo, Hongwei; Jiang, Junguang; Shi, Yingyan; Wang, Yuling; Dong, Shaojun

    2007-05-01

    The spectrophotometric titration by sodium hydroxide of 5,10,15-triphenyl-20-(4-hydroxyphenyl)porphyrin ((OH)(1)PH(2)) is studied as a function of solvent composition of DMF-H(2)O binary solvent mixture ([OH(-)]=0.04 M). Combining the structure changes of the porphyrin and the "four orbital" model of Gouterman, many features of the optical spectra of this deprotonated para-hydroxy-substituted tetraphenylporphyrin in different composition of binary solvent mixtures can be rationalized. In highly aqueous solvents, the changes of the titration curves are shown to be mainly due to hydrogen-bonding of the oxygen of the phenoxide anion group by the hydroxylic solvent, Which decreases the energy of the phenoxide anion pi orbital. Thus the phenoxide anion pi orbital cannot cross over the porphyrin pi orbital being a different HOMO. However, its energy is close to that of the porphyrin pi orbitals. As a result, in the visible region, no charge-transfer band is observed, while in the visible-near region, the Soret peak split into two components. In nonaqueous solvents, the changes are mainly attributed to further deprotonation of pyrrolic-Hs of (OH)(1)PH(2) by NaOH and coordination with two sodium ions to form the sodium complex of (OH)(1)PH(2), which turns hyperporphyrin spectra of deprotonated of phenolic-H of (OH)(1)PH(2) into three-banded spectra of regular metalloporphyrin.

  13. The frequent 5,10-methylenetetrahydrofolate reductase C677T polymorphism is associated with a common haplotype in whites, Japanese, and Africans.

    PubMed

    Rosenberg, Nurit; Murata, Mitsuru; Ikeda, Yasuo; Opare-Sem, Ohene; Zivelin, Ariella; Geffen, Eli; Seligsohn, Uri

    2002-03-01

    The common 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism causes decreased activity of this enzyme and can be associated with mild-to-moderate hyperhomocysteinemia in homozygotes, particularly when there is folic acid deficiency, as well as with vascular dementia, arterial thrombosis, venous thrombosis, neural-tube defects, and fetal loss. When folic acid intake is sufficient, homozygotes for MTHFR 677T appear to be protected against colon cancer and acute lymphatic leukemia, and fetuses bearing this genotype have an augmented survival. The distribution of MTHFR 677T is worldwide, but its frequency in different populations varies extensively. In the present study, we addressed the question of whether the MTHFR 677T alteration has an ancestral origin or has occurred repeatedly. We analyzed the frequency distribution of the previously described polymorphism A1298C in exon 7 and of three intronic dimorphisms, in white Israelis (Jews and Arabs), Japanese, and Ghanaian Africans. The 677T allele was, remarkably, associated with one haplotype, G-T-A-C, in white and Japanese homozygotes. Among the Africans, analysis of maximum likelihood also disclosed an association with the G-T-A-C haplotype, although none of the 174 subjects examined was homozygous for MTHFR 677T. These results suggest that the MTHFR 677T alteration occurred on a founder haplotype that may have had a selective advantage. PMID:11781870

  14. Mössbauer effect study of tight spin coupling in oxidized chloro-5,10,15,20- tetra(mesityl)porphyrinatoiron(III)

    NASA Astrophysics Data System (ADS)

    Boso, Brian; Lang, George; McMurry, Thomas J.; Groves, John T.

    1983-08-01

    Mössbauer spectra of a polycrystalline form of oxidized chloro-5,10,15,20-tetra(mesityl)porphyrin- atoiron(III) [Fe(TMP)Cl], compound A, were recorded over a range of temperatures (4.2-195 K) and magnetic fields (0-6 T). These spectra of compound A exhibit magnetic features which are markedly different from those of the analogous protein complexes, horse radish peroxidase compound I (HRP-I) and compound ES of cytochrome c peroxidase, even though chemical evidence and optical spectroscopy indicate that compound A is similar to the others in comprising a Fe(IV) complex within a porphyrin cation radical. We interpret the data by employing a spin Hamiltonian model in which the central Fe(IV) complex, with S=1, is tightly coupled to a S=1/2 system of the oxidized porphyrin to yield a net S=3/2 system as suggested by the susceptibility measurements. The theoretical treatment yields information on the d-electron energies which is similar to that more directly available in the peroxidase spectra. The strength of the axial crystal field is found to increase progressively in the series HRP-I, ES, compound A, while the spin coupling in A is the strongest of the three by several orders of magnitude. The good fits to experimental data confirm the efficacy of the theoretical treatment which may be applicable to a variety of other coupled systems.

  15. The effect of laser activation of 5,10,15,20-tetra-sulphophenyl-porphyrin loaded in K562 cells and human normal mononuclear cells.

    PubMed

    Constantin, Carolina; Neagu, Monica; Manda, Gina; Ion, Rodica-Mariana; Iordăchescu, Dana Iord

    2004-01-01

    Photodynamic therapy (PDT) is a relatively new type of treatment in cancer, based on a photosensitizer, visible light and molecular oxygen. Reactive oxygen species are generated, causing tumor cells death by apoptosis or necrosis. Significant nowadays research efforts are focused on finding new photosensitizers with antineoplastic activity and an acceptable toxicological profile. Although consistent information exists regarding PDT in solid tumors, relatively few data are available for PDT of blood cancers. Therefore, we carried out a comparative study on lymphoblastic K562 cells and human normal peripheral blood mononuclear cells (PBMC) treated at a density of 2 x 10(5) cells/mL with 5,10,15,20-tetra-sulphophenyl-porphyrin (TSPP) and then irradiated with He-Ne laser light (lamda = 632.8 nm). The following cell functions were investigated: viability, multiplication, RNA synthesis, total RNA levels and apoptosis. After irradiation, the viability of TSPP-loaded tumor cells decrease, the multiplication rate and the total RNA level are drastically reduced and cells undergo apoptosis. TSPP alone loaded into cells but not activated by irradiation, does not affect these cell parameters. Human normal PBMC subjected to TSPP loading and laser-irradiation develop a different cellular response, their viability and proliferative capacity not being altered by experimental PDT. Accordingly, it appears that TSPP is a non-aggressive compound for cellular physiology and becomes cytotoxic only by irradiation; moreover laser-activated TSPP affects only cells that have a tumoral pattern.

  16. Novel nanomaterials based on 5,10,15,20-tetrakis(3,4-dimethoxyphenyl)-21H,23H-porphyrin entrapped in silica matrices

    SciTech Connect

    Fagadar-Cosma, Eugenia; Enache, Corina; Vlascici, Dana; Fagadar-Cosma, Gheorghe; Vasile, Mihaela; Bazylak, Grzegorz

    2009-12-15

    The present study is dealing with the obtaining of transparent hybrid silica materials encapsulating 5,10,15,20-tetrakis(3,4-dimethoxyphenyl)-21H,23H-porphyrin designated for advanced optoelectronic devices. The porphyrin was synthesized by three methods: an Adler-type reaction between pyrrole and 3,4-dimethoxybenzaldehyde in propionic acid medium; by Lindsey condensation of pyrrole with 3,4-dimethoxybenzaldehyde in the presence of BF{sub 3}.OEt{sub 2} and by a multicomponent reaction by simultaneously using of pyrrole and two different aldehydes: 3,4-dimethoxybenzaldehyde and 3-hydroxybenzaldehyde. The 3,4-dimethoxyphenyl substituted porphyrin was characterized by HPLC, TLC, UV-vis, FT-IR, {sup 1}H NMR and {sup 13}C NMR analysis. Excitation and emission spectra were also discussed in terms of pH conditions. The hybrid materials, consisting in the porphyrin encapsulated in silica matrices, have been prepared successfully via the two steps acid-base catalyzed hydrolysis and condensation of tetraethylorthosilicate using different approaches of the sol-gel process: in situ, by impregnation and by sonication. The synthetic conditions and the compositions were monitored and characterized by using spectroscopic methods such as FT-IR, fluorescence and UV-vis. Atomic force microscopy (AFM) has been applied to observe the columnar or pyramidal nanostructures which are formed by the immobilization of porphyrin on the silica matrices.

  17. Iodinin (1,6-Dihydroxyphenazine 5,10-Dioxide) from Streptosporangium sp. Induces Apoptosis Selectively in Myeloid Leukemia Cell Lines and Patient Cells

    PubMed Central

    Myhren, Lene E.; Nygaard, Gyrid; Gausdal, Gro; Sletta, Håvard; Teigen, Knut; Degnes, Kristin F.; Zahlsen, Kolbjørn; Brunsvik, Anders; Bruserud, Øystein; Døskeland, Stein Ove; Selheim, Frode; Herfindal, Lars

    2013-01-01

    Despite recent improvement in therapy, acute myeloid leukemia (AML) is still associated with high lethality. In the presented study, we analyzed the bioactive compound iodinin (1,6-dihydroxyphenazine 5,10-dioxide) from a marine actinomycetes bacterium for the ability to induce cell death in a range of cell types. Iodinin showed selective toxicity to AML and acute promyelocytic (APL) leukemia cells, with EC50 values for cell death up to 40 times lower for leukemia cells when compared with normal cells. Iodinin also successfully induced cell death in patient-derived leukemia cells or cell lines with features associated with poor prognostic such as FLT3 internal tandem duplications or mutated/deficient p53. The cell death had typical apoptotic morphology, and activation of apoptotic signaling proteins like caspase-3. Molecular modeling suggested that iodinin could intercalate between bases in the DNA in a way similar to the anti-cancer drug daunorubicin (DNR), causing DNA-strand breaks. Iodinin induced apoptosis in several therapy-resistant AML-patient blasts, but to a low degree in peripheral blood leukocytes, and in contrast to DNR, not in rat cardiomyoblasts. The low activity towards normal cell types that are usually affected by anti-leukemia therapy suggests that iodinin and related compounds represent promising structures in the development of anti-cancer therapy. PMID:23364682

  18. Attachment for sucker rod depth adjustment

    SciTech Connect

    Collins, N.D.

    1992-04-07

    This patent describes a surface unit of an oil well pumping system, having a walking beam, a suspended carrier bar and an interconnected sucker rod assembly for stroking a reciprocating down-hole pump. It comprises a cross bar having a centrally located passage therein for the sucker rod assembly and adapted to be transversely supported by the carrier bar; a depth adjusting bar, having a centrally located passage therein for the sucker rod assembly, positioned at a selected fixed dimension above and parallel to the cross bar and adapted to operatively support the sucker rod assembly; clamping means for fixing the sucker rod relative to the depth adjusting bar; and hydraulically extendable means supportively connecting the depth adjusting bar to the cross bar on at least each side of the carrier bar for adjusting the selected fixed dimension and maintaining the adjustment during operation.

  19. Eye movements in depth to visual illusions

    NASA Astrophysics Data System (ADS)

    Wismeijer, D. A.

    2009-10-01

    We perceive the three-dimensional (3D) environment that surrounds us with deceptive effortlessness. In fact, we are far from comprehending how the visual system provides us with this stable perception of the (3D) world around us. This thesis will focus on the interplay between visual perception of depth and its closely related action system, eye movements in depth. The human visual system is comprised of a sensory (input) and an output (motor) system. Processed information from the sensory system can result in two explicit measurable response types: conscious visual perception and ocular motor behavior. It is still a matter of debate whether conscious visual perception and action (including hand- and arm-movements) use the same information or whether the visual system has separate channels processing information for perception and action. In this thesis, we study (1) if separate channels, one for eye movements and one for conscious visual perception, indeed exist, and (2) if so, if there is a direct input from the perceptual pathway to the motor pathway. Assuming that either eye movements and conscious visual perception are based on information from a common source (a negative answer to issue 1) or perception can directly influence, or guide, eye movements (an affirmative answer to research question 2), (eye) movements reflect our conscious visual perception. If so, eye movements could provide us with an alternative method to probe our conscious visual perception, making explicit perceptual reports superfluous. In this thesis we focus on depth perception and the two types of eye movements that are closest related to depth perception, namely vergence (an eye movement that gets a certain depth plane into focus) and saccades (a rapid eye movement to change gaze direction). Over the last 20 years it has been shown that depth perception is based on a weighted combination of depth cues available such as linear perspective, occlusion and binocular disparity. How eye

  20. Depth profile characterization with noncollinear beam mixing

    SciTech Connect

    Freed, Shaun L. E-mail: jeong.na@wyle.com; Na, Jeong K. E-mail: jeong.na@wyle.com

    2015-03-31

    Noncollinear beam mixing is an ultrasonic approach to quantify elastic nonlinearity within a subsurface volume of material. The technique requires interaction between two beams of specific frequency, angle, and vibration mode to generate a third beam propagating from the intersection volume. The subsurface depth to interaction zone is controlled by changing the separation distance between the two input transducers, and the amplitude of the third generated beam is proportional to the elastic nonlinearity within the interaction zone. Therefore, depth profiling is possible if a suitable parameter is established to normalize the detected signal independent of propagation distances and input amplitudes. This foundational effort has been conducted toward developing such a parameter for depth profile measurements in homogeneous aluminum that includes corrective terms for attenuation, beam overlap noise, beam spread, and input amplitudes. Experimental and analytical results are provided, and suggested applications and improvements are discussed toward characterizing subsurface material property profiles.