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Sample records for early decomposition observation

  1. Evidence for Early Morphological Decomposition: Combining Masked Priming with Magnetoencephalography

    PubMed Central

    Lehtonen, Minna; Monahan, Philip J.; Poeppel, David

    2015-01-01

    Are words stored as morphologically structured representations? If so, when during word recognition are morphological pieces accessed? Recent masked priming studies support models that assume early decomposition of (potentially) morphologically complex words. The electrophysiological evidence, however, is inconsistent. We combined masked morphological priming with magneto-encephalography (MEG), a technique particularly adept at indexing processes involved in lexical access. The latency of an MEG component peaking, on average, 220 msec post-onset of the target in left occipito-temporal brain regions was found to be sensitive to the morphological prime– target relationship under masked priming conditions in a visual lexical decision task. Shorter latencies for related than unrelated conditions were observed both for semantically transparent (cleaner–CLEAN) and opaque (corner–CORN) prime–target pairs, but not for prime–target pairs with only an orthographic relationship (brothel–BROTH). These effects are likely to reflect a prelexical level of processing where form-based representations of stems and affixes are represented and are in contrast to models positing no morphological structure in lexical representations. Moreover, we present data regarding the transitional probability from stem to affix in a post hoc comparison, which suggests that this factor may modulate early morphological decomposition, particularly for opaque words. The timing of a robust MEG component sensitive to the morphological relatedness of prime–target pairs can be used to further understand the neural substrates and the time course of lexical processing. PMID:21557645

  2. Evidence for Early Morphological Decomposition: Combining Masked Priming with Magnetoencephalography

    ERIC Educational Resources Information Center

    Lehtonen, Minna; Monahan, Philip J.; Poeppel, David

    2011-01-01

    Are words stored as morphologically structured representations? If so, when during word recognition are morphological pieces accessed? Recent masked priming studies support models that assume early decomposition of (potentially) morphologically complex words. The electrophysiological evidence, however, is inconsistent. We combined masked…

  3. Young Children's Thinking about Decomposition: Early Modeling Entrees to Complex Ideas in Science

    ERIC Educational Resources Information Center

    Ero-Tolliver, Isi; Lucas, Deborah; Schauble, Leona

    2013-01-01

    This study was part of a multi-year project on the development of elementary students' modeling approaches to understanding the life sciences. Twenty-three first grade students conducted a series of coordinated observations and investigations on decomposition, a topic that is rarely addressed in the early grades. The instruction included…

  4. Density dependence of isospin observables in spinodal decomposition

    E-print Network

    M. Colonna; F. Matera

    2008-05-15

    Isotopic fluctuations in fragment formation are investigated in a quasi-analytical description of the spinodal decomposition scenario. By exploiting the fluctuation-dissipation relations the covariance matrix of density fluctuations is derived as a function of the wave vector for nuclear matter at given values of density, charge asymmetry, temperature, and of the time that the system spends in the instability region. Then density fluctuations in ordinary space are implemented with a Fourier transform performed in a finite cubic lattice. Inside this box, domains with different density coexist, from which clusters of nucleons eventually emerge. Within our approach, the isotopic distributions are determined by the N/Z ratio of the leading unstable isoscalarlike mode and by isovectorlike fluctuations present in the matter undergoing the spinodal decomposition. Hence the average value of the N/Z ratio of clusters and the width of the relative distribution reflect the properties of the symmetry energy. Generating a large number of events, these calculations allow a careful investigation of the cluster isotopic content as a function of the cluster density. A uniform decrease of the average charge asymmetry and of the width of the isotopic distributions with increasing density is observed. Finally we remark that the results essentially refer to the early break--up of the system.

  5. Decomposition

    USGS Publications Warehouse

    Middleton, Beth A.

    2014-01-01

    A cornerstone of ecosystem ecology, decomposition was recognized as a fundamental process driving the exchange of energy in ecosystems by early ecologists such as Lindeman 1942 and Odum 1960). In the history of ecology, studies of decomposition were incorporated into the International Biological Program in the 1960s to compare the nature of organic matter breakdown in various ecosystem types. Such studies still have an important role in ecological studies of today. More recent refinements have brought debates on the relative role microbes, invertebrates and environment in the breakdown and release of carbon into the atmosphere, as well as how nutrient cycling, production and other ecosystem processes regulated by decomposition may shift with climate change. Therefore, this bibliography examines the primary literature related to organic matter breakdown, but it also explores topics in which decomposition plays a key supporting role including vegetation composition, latitudinal gradients, altered ecosystems, anthropogenic impacts, carbon storage, and climate change models. Knowledge of these topics is relevant to both the study of ecosystem ecology as well projections of future conditions for human societies.

  6. Decomposition of sensitivity of the symmetry energy observables

    E-print Network

    He-Lei Liu; Gao-Chan Yong; De-Hua Wen

    2015-03-31

    To exactly answer which density region that some frequently used symmetry-energy-sensitive observables probe, for the first time, we make a study of decomposition of the sensitivity of some symmetry-energy-sensitive observables. It is found that for the Au+Au reaction at incident beam energies of 200 and 400 MeV/nucleon, frequently used symmetry-energy-sensitive observables mainly probe the density-dependent symmetry energy around 1.25$\\rho_{0}$ (for pionic observables) or 1.5$\\rho_{0}$ (for nucleonic observables). Effects of the symmetry energy in the low-density region is in general small but observable. The fact that the symmetry-energy-sensitive observables are not sensitive to the symmetry energy in the maximal baryon-density region increases the difficulty of studying nuclear symmetry energy at super-density.

  7. Decomposition of surface drifter observations in the Atlantic Ocean Rick Lumpkin

    E-print Network

    Decomposition of surface drifter observations in the Atlantic Ocean Rick Lumpkin Cooperative and techniques. Citation: Lumpkin, R., Decomposition of surface drifter observations in the Atlantic Ocean are usually examined in the framework of a decomposition in which a record y(t) is divided into mean and eddy

  8. Evidence for Early Morphological Decomposition in Visual Word Recognition

    ERIC Educational Resources Information Center

    Solomyak, Olla; Marantz, Alec

    2010-01-01

    We employ a single-trial correlational MEG analysis technique to investigate early processing in the visual recognition of morphologically complex words. Three classes of affixed words were presented in a lexical decision task: free stems (e.g., taxable), bound roots (e.g., tolerable), and unique root words (e.g., vulnerable, the root of which…

  9. Polar decomposition for attitude determination from vector observations

    NASA Technical Reports Server (NTRS)

    Bar-Itzhack, Itzhack Y.

    1993-01-01

    This work treats the problem of weighted least squares fitting of a 3D Euclidean-coordinate transformation matrix to a set of unit vectors measured in the reference and transformed coordinates. A closed-form analytic solution to the problem is re-derived. The fact that the solution is the closest orthogonal matrix to some matrix defined on the measured vectors and their weights is clearly demonstrated. Several known algorithms for computing the analytic closed form solution are considered. An algorithm is discussed which is based on the polar decomposition of matrices into the closest unitary matrix to the decomposed matrix and a Hermitian matrix. A somewhat longer improved algorithm is suggested too. A comparison of several algorithms is carried out using simulated data as well as real data from the Upper Atmosphere Research Satellite. The comparison is based on accuracy and time consumption. It is concluded that the algorithms based on polar decomposition yield a simple although somewhat less accurate solution. The precision of the latter algorithms increase with the number of the measured vectors and with the accuracy of their measurement.

  10. Evidence from neglect dyslexia for morphological decomposition at the early stages of orthographic-visual analysis

    PubMed Central

    Reznick, Julia; Friedmann, Naama

    2015-01-01

    This study examined whether and how the morphological structure of written words affects reading in word-based neglect dyslexia (neglexia), and what can be learned about morphological decomposition in reading from the effect of morphology on neglexia. The oral reading of 7 Hebrew-speaking participants with acquired neglexia at the word level—6 with left neglexia and 1 with right neglexia—was evaluated. The main finding was that the morphological role of the letters on the neglected side of the word affected neglect errors: When an affix appeared on the neglected side, it was neglected significantly more often than when the neglected side was part of the root; root letters on the neglected side were never omitted, whereas affixes were. Perceptual effects of length and final letter form were found for words with an affix on the neglected side, but not for words in which a root letter appeared in the neglected side. Semantic and lexical factors did not affect the participants' reading and error pattern, and neglect errors did not preserve the morpho-lexical characteristics of the target words. These findings indicate that an early morphological decomposition of words to their root and affixes occurs before access to the lexicon and to semantics, at the orthographic-visual analysis stage, and that the effects did not result from lexical feedback. The same effects of morphological structure on reading were manifested by the participants with left- and right-sided neglexia. Since neglexia is a deficit at the orthographic-visual analysis level, the effect of morphology on reading patterns in neglexia further supports that morphological decomposition occurs in the orthographic-visual analysis stage, prelexically, and that the search for the three letters of the root in Hebrew is a trigger for attention shift in neglexia. PMID:26528159

  11. Early stages of spinodal decomposition in Fe-Cr resolved by in-situ small-angle neutron scattering

    NASA Astrophysics Data System (ADS)

    Hörnqvist, M.; Thuvander, M.; Steuwer, A.; King, S.; Odqvist, J.; Hedström, P.

    2015-02-01

    In-situ, time-resolved small-angle neutron scattering (SANS) investigations of the early stages of the spinodal decomposition process in Fe-35Cr were performed at 773 and 798 K. The kinetics of the decomposition, both in terms of characteristic distance and peak intensity, followed a power-law behaviour from the start of the heat treatment (a'= 0.10-0.11 and a? = 0.67-0.86). Furthermore, the method allows tracking of the high-Q slope, which is a sensitive measure of the early stages of decomposition. Ex-situ SANS and atom probe tomography were used to verify the results from the in-situ investigations. Finally, the in-situ measurement of the evolution of the characteristic distance at 773 K was compared with the predictions from the Cahn-Hilliard-Cook model, which showed good agreement with the experimental data (a'= 0.12-0.20 depending on the assumed mobility).

  12. Early Observations of Sunspots: Scheiner and Galileo

    NASA Astrophysics Data System (ADS)

    Casanovas, J.

    There had been occasional observations of spots on the Sun since antiquity. Kepler observed a sunspot in 1607 but he interpreted it as a Mercury's transit. One year after the introduction of the telescope astronomers identified spots on the Sun. J. Fabricius was the first to print a book on sunspots at the end of 1611, but this book had little diffusion. Fabricius rightly thought that the spots belonged to the Sun. The Jesuit C. Scheiner independently observed sunspots on the Sun and he announced his discovery at the end of 1611 in three letters under the pseudonym Apelles. Scheiner failed to observe the returning of the spots and hence did not recognize the solar rotation. Therefore he preferred to see the spots as caused by little bodies orbiting the Sun. Based on Scheiner's observations, Kepler concluded that the spots were on the solar surface like dross floating on melted metal. When Scheiner's letters reached Italy, Galileo claimed to have observed sunspots much earlier, but if this had been the case, he had not published anything on sunspots. Galileo replied to Apelles' letters affirming that the spots were on the surface of the Sun, like clouds. A bitter and long fight followed between Galileo and Scheiner on the priority of discovery. Techniques for solar observation progressed quickly. The solar image was observed projected on a white paper for measurement of sunspots positions. Scheiner later perfected this method installing the telescope on an equatorial mounting. Scheiner made over 2000 solar observations and determined the orientation of the solar axis of rotation. His methods and results were presented in his monumental work Rosa Ursina.

  13. Early stages of spinodal decomposition in Fe–Cr resolved by in-situ small-angle neutron scattering

    SciTech Connect

    Hörnqvist, M. Thuvander, M.; Steuwer, A.; King, S.; Odqvist, J.; Hedström, P.

    2015-02-09

    In-situ, time-resolved small-angle neutron scattering (SANS) investigations of the early stages of the spinodal decomposition process in Fe–35Cr were performed at 773 and 798?K. The kinetics of the decomposition, both in terms of characteristic distance and peak intensity, followed a power-law behaviour from the start of the heat treatment (a?{sup ?}=?0.10–0.11 and a??=?0.67–0.86). Furthermore, the method allows tracking of the high–Q slope, which is a sensitive measure of the early stages of decomposition. Ex-situ SANS and atom probe tomography were used to verify the results from the in-situ investigations. Finally, the in-situ measurement of the evolution of the characteristic distance at 773?K was compared with the predictions from the Cahn-Hilliard-Cook model, which showed good agreement with the experimental data (a?{sup ?}=?0.12–0.20 depending on the assumed mobility)

  14. Unimolecular thermal decomposition of phenol and d5-phenol: Direct observation of cyclopentadiene formation via cyclohexadienone

    NASA Astrophysics Data System (ADS)

    Scheer, Adam M.; Mukarakate, Calvin; Robichaud, David J.; Nimlos, Mark R.; Carstensen, Hans-Heinrich; Barney Ellison, G.

    2012-01-01

    The pyrolyses of phenol and d5-phenol (C6H5OH and C6D5OH) have been studied using a high temperature, microtubular (?tubular) SiC reactor. Product detection is via both photon ionization (10.487 eV) time-of-flight mass spectrometry and matrix isolation infrared spectroscopy. Gas exiting the heated reactor (375 K-1575 K) is subject to a free expansion after a residence time in the ?tubular reactor of approximately 50-100 ?s. The expansion from the reactor into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. We find that the initial decomposition steps at the onset of phenol pyrolysis are enol/keto tautomerization to form cyclohexadienone followed by decarbonylation to produce cyclopentadiene; C6H5OH ? c-C6H6 = O ? c-C5H6 + CO. The cyclopentadiene loses a H atom to generate the cyclopentadienyl radical which further decomposes to acetylene and propargyl radical; c-C5H6 ? c-C5H5 + H ? HC?CH + HCCCH2. At higher temperatures, hydrogen loss from the PhO-H group to form phenoxy radical followed by CO ejection to generate the cyclopentadienyl radical likely contributes to the product distribution; C6H5O-H ? C6H5O + H ? c-C5H5 + CO. The direct decarbonylation reaction remains an important channel in the thermal decomposition mechanisms of the dihydroxybenzenes. Both catechol (o-HO-C6H4-OH) and hydroquinone (p-HO-C6H4-OH) are shown to undergo decarbonylation at the onset of pyrolysis to form hydroxycyclopentadiene. In the case of catechol, we observe that water loss is also an important decomposition channel at the onset of pyrolysis.

  15. Indium hydroxide to oxide decomposition observed in one nanocrystal during in situ transmission electron microscopy studies

    SciTech Connect

    Miehe, Gerhard; Lauterbach, Stefan; Kleebe, Hans-Joachim; Gurlo, Aleksander

    2013-02-15

    The high-resolution transmission electron microscopy (HR-TEM) is used to study, in situ, spatially resolved decomposition in individual nanocrystals of metal hydroxides and oxyhydroxides. This case study reports on the decomposition of indium hydroxide (c-In(OH){sub 3}) to bixbyite-type indium oxide (c-In{sub 2}O{sub 3}). The electron beam is focused onto a single cube-shaped In(OH){sub 3} crystal of {l_brace}100{r_brace} morphology with ca. 35 nm edge length and a sequence of HR-TEM images was recorded during electron beam irradiation. The frame-by-frame analysis of video sequences allows for the in situ, time-resolved observation of the shape and orientation of the transformed crystals, which in turn enables the evaluation of the kinetics of c-In{sub 2}O{sub 3} crystallization. Supplementary material (video of the transformation) related to this article can be found online at (10.1016/j.jssc.2012.09.022). After irradiation the shape of the parent cube-shaped crystal is preserved, however, its linear dimension (edge) is reduced by the factor 1.20. The corresponding spotted selected area electron diffraction (SAED) pattern representing zone [001] of c-In(OH){sub 3} is transformed to a diffuse strongly textured ring-like pattern of c-In{sub 2}O{sub 3} that indicates the transformed cube is no longer a single crystal but is disintegrated into individual c-In{sub 2}O{sub 3} domains with the size of about 5-10 nm. The induction time of approximately 15 s is estimated from the time-resolved Fourier transforms. The volume fraction of the transformed phase (c-In{sub 2}O{sub 3}), calculated from the shrinkage of the parent c-In(OH){sub 3} crystal in the recorded HR-TEM images, is used as a measure of the kinetics of c-In{sub 2}O{sub 3} crystallization within the framework of Avrami-Erofeev formalism. The Avrami exponent of {approx}3 is characteristic for a reaction mechanism with fast nucleation at the beginning of the reaction and subsequent three-dimensional growth of nuclei with a constant growth rate. The structural transformation path in reconstructive decomposition of c-In(OH){sub 3} to c-In{sub 2}O{sub 3} is discussed in terms of (i) the displacement of hydrogen atoms that lead to breaking the hydrogen bond between OH groups of [In(OH){sub 6}] octahedra and finally to their destabilization and (ii) transformation of the vertices-shared indium-oxygen octahedra in c-In(OH){sub 3} to vertices- and edge-shared octahedra in c-In{sub 2}O{sub 3}. - Graphical abstract: Frame-by-frame analysis of video sequences recorded of HR-TEM images reveals that a single cube-shaped In(OH){sub 3} nanocrystal with {l_brace}100{r_brace} morphology decomposes into bixbyite-type In{sub 2}O{sub 3} domains while being imaged. The mechanism of this decomposition is evaluated through the analysis of the structural relationship between initial (c-In(OH){sub 3}) and transformed (c-In{sub 2}O{sub 3}) phases and though the kinetics of the decomposition followed via the time-resolved shrinkage of the initial crystal of indium hydroxide. Highlights: Black-Right-Pointing-Pointer In-situ time-resolved High Resolution Transmission Electron Microscopy. Black-Right-Pointing-Pointer Crystallographic transformation path. Black-Right-Pointing-Pointer Kinetics of the decomposition in one nanocrystal.

  16. The Early Years: Observing with Magnifiers

    ERIC Educational Resources Information Center

    Ashbrook, Peggy

    2008-01-01

    Inspire your students to become detailed observers by encouraging the use of magnifiers. Magnification can make us see an object with new understanding. Rachel Carson said, "Some of nature's most exquisite handiwork is on a miniature scale, as anyone knows who has applied a magnifying glass to a snowflake"(Carson 1965). The lesson described here…

  17. SOAR remote observing: tactics and early results

    NASA Astrophysics Data System (ADS)

    Cecil, Gerald N.; Crain, J. Adam

    2004-09-01

    Travel from North America to the 4.1m SOAR telescope atop Cerro Pachon exceeds $1000, and takes >16 hours door to door (20+ hours typically). SOAR aims to exploit best seeing, requiring dynamic scheduling that is impossible to accomplish when catering to peripatetic astronomers. According to technical arguments at www.peakoil.org, we are near the peak rate of depleting world petroleum, so can expect travel costs to climb sharply. With the telecom bubble's glut of optical fiber, we can transmit data more efficiently than astronomers and "observe remotely". With data compression, less than half of the 6 Mbps bandwidth shared currently by SOAR and CTIO is enough to enable a high-fidelity observing presence for SOAR partners in North America, Brazil, and Chile. We discuss access from home by cable modem/DSL link.

  18. Unimolecular Thermal Decomposition of Phenol and d5-Phenol: Direct Observation of Cyclopentadiene Formation via Cyclohexadienone

    SciTech Connect

    Scheer, A. M.; Mukarakate, C.; Robichaud, D. J.; Nimlos, M. R.; Carstensen, H. H.; Barney, E. G.

    2012-01-28

    The pyrolyses of phenol and d{sub 5}-phenol (C{sub 6}H{sub 5}OH and C{sub 6}D{sub 5}OH) have been studied using a high temperature, microtubular ({mu}tubular) SiC reactor. Product detection is via both photon ionization (10.487 eV) time-of-flight mass spectrometry and matrix isolation infrared spectroscopy. Gas exiting the heated reactor (375 K-1575 K) is subject to a free expansion after a residence time in the {mu}tubular reactor of approximately 50-100 {micro}s. The expansion from the reactor into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. We find that the initial decomposition steps at the onset of phenol pyrolysis are enol/keto tautomerization to form cyclohexadienone followed by decarbonylation to produce cyclopentadiene; C{sub 6}H{sub 5}OH {yields} c-C{sub 6}H{sub 6} = O {yields} c-C{sub 5}H{sub 6} + CO. The cyclopentadiene loses a H atom to generate the cyclopentadienyl radical which further decomposes to acetylene and propargyl radical; c-C{sub 5}H{sub 6} {yields} c-C{sub 5}H{sub 5} + H {yields} HC {triple_bond} CH + HCCCH{sub 2}. At higher temperatures, hydrogen loss from the PhO-H group to form phenoxy radical followed by CO ejection to generate the cyclopentadienyl radical likely contributes to the product distribution; C{sub 6}H{sub 5}O-H {yields} C{sub 6}H{sub 5}O + H {yields} c-C{sub 5}H{sub 5} + CO. The direct decarbonylation reaction remains an important channel in the thermal decomposition mechanisms of the dihydroxybenzenes. Both catechol (o-HO-C{sub 6}H{sub 4}-OH) and hydroquinone (p-HO-C{sub 6}H{sub 4}-OH) are shown to undergo decarbonylation at the onset of pyrolysis to form hydroxycyclopentadiene. In the case of catechol, we observe that water loss is also an important decomposition channel at the onset of pyrolysis.

  19. ALMA observations during its first early science cycles

    NASA Astrophysics Data System (ADS)

    Nyman, Lars-Åke; Cox, Pierre; Corder, Stuartt; Saito, Masao; Lundgren, Andreas; Vila-Vilaro, Baltasar; Espada, Daniel; Villard, Eric; Barrios, Emilio; Andreani, Paola; Hibbard, John; Tatematsu, Ken'ichi

    2014-08-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) is a new interferometer operated on Llano de Chajnantor at 5050 m altitude in the Chilean Andes. It consists of 66 antennas operating in the mm/submm windows between 3 and 0.3 mm wavelength. Early science observations using 16 antennas (known as Cycle 0) started in parallel with construction in September 2011, in order to provide useful results to the astronomy community and to facilitate the ongoing characterization of its system. ALMA is currently in Cycle 2 of early science observations. This presentation describes the development and progress of ALMA observations and data processing from Cycle 0 towards full operations.

  20. Active Control of Jet Noise Using Observable Inferred Decomposition and Large Window PIV

    NASA Astrophysics Data System (ADS)

    Berger, Zachary; Berry, Matthew; Low, Kerwin; Cordier, Laurent; Noack, Bernd; Gogineni, Sivaram; Glauser, Mark

    2012-11-01

    In this investigation, we seek to find sources of noise created in the near-region of a highly subsonic jet, with a nozzle diameter of 2''. Using large window PIV alongside simultaneous hydrodynamic and acoustic pressure, we focus on observing flow structures created in the collapse of the potential core. Correlations can be made between the low-dimensional velocity field (using POD) and the far-field acoustics in an effort to identify loud modes in the flow. An advanced reduced order model known as Observable Inferred Decomposition (OID) is used to form closed-loop controllers for noise reduction in the far-field. With this technique, we find low-dimensional representations of near-field velocity and far-field pressure - finding a linear mapping between the two fields. Then, we obtain acoustically optimized modes in the flow field and seek to drive these modes to zero using active control strategies. For flow control, synthetic jet actuators are used as shear layer excitation. A large range of tests are explored, varying Mach number and flow control configurations. Finally, large PIV windows will allow us to investigate several diameters of the flow field in the streamwise plane.

  1. Decomposition Rate and Pattern in Hanging Pigs.

    PubMed

    Lynch-Aird, Jeanne; Moffatt, Colin; Simmons, Tal

    2015-09-01

    Accurate prediction of the postmortem interval requires an understanding of the decomposition process and the factors acting upon it. A controlled experiment, over 60 days at an outdoor site in the northwest of England, used 20 freshly killed pigs (Sus scrofa) as human analogues to study decomposition rate and pattern. Ten pigs were hung off the ground and ten placed on the surface. Observed differences in the decomposition pattern required a new decomposition scoring scale to be produced for the hanging pigs to enable comparisons with the surface pigs. The difference in the rate of decomposition between hanging and surface pigs was statistically significant (p=0.001). Hanging pigs reached advanced decomposition stages sooner, but lagged behind during the early stages. This delay is believed to result from lower variety and quantity of insects, due to restricted beetle access to the aerial carcass, and/or writhing maggots falling from the carcass. PMID:26249126

  2. Natural Killer Activity: Early Days, Advances, and Seminal Observations

    PubMed Central

    Ortaldo, John R.; Wiltrout, Robert H.; Reynolds, Craig W.

    2014-01-01

    This manuscript describes the early history of NK cell discovery, with emphasis on the events in the first decade of NK cell studies, 1972–1982. The authors highlight some of the earliest and most important observations that would later prove to be milestones in the study of NK cells and their activity. PMID:24941370

  3. Direct observation of roaming radicals in the thermal decomposition of acetaldehyde.

    SciTech Connect

    Sivaramakrishnan, R.; Michael, J. V.; Klippenstein, S. J.; Chemical Sciences and Engineering Division

    2010-01-21

    The thermal dissociation of acetaldehyde has been studied with the reflected shock tube technique using H(D)-atom atomic resonance absorption spectrometry detection. The use of an unreversed light source yields extraordinarily sensitive H atom detection. As a result, we are able to measure both the total decomposition rate and the branching to radical versus molecular channels. This branching provides a direct measure of the contribution from the roaming radical mechanism since the contributions from the usual tight transition states are predicted by theory to be negligible. The experimental observations also provide a measure of the rate coefficient for H + CH{sub 3}CHO. Another set of experiments employing C{sub 2}H{sub 5}I as an H-atom source provides additional data for this rate coefficient that extends to lower temperature. An evaluation of the available experimental results for H + CH{sub 3}CHO can be expressed by a three-parameter Arrhenius expression as k = 7.66 x 10{sup -20}T{sup 2.75} exp((-486 K)/T) cm{sup 3} molecule{sup -1} s{sup -1} (298-1415 K). Analogous experiments employing C{sub 2}D{sub 5}I as a D-atom source allow for the study of the isotopically substituted reaction. The present experiments are the only direct measure for this reaction rate constant, and the results can be expressed by an Arrhenius expression as k = 5.20 x 10{sup -10} exp((-4430 K)/T) cm{sup 3} molecule{sup -1} s{sup -1} (1151-1354 K). The H/D + CH{sub 3}CHO reactions are also studied with ab initio transition-state theory, and the results are in remarkably good agreement with the current experimental data.

  4. Preliminary observations of the decomposition of crown-of-thorns starfish, Acanthaster planci (L.)

    NASA Astrophysics Data System (ADS)

    Moran, P. J.

    1992-07-01

    The rate of decomposition of 67 crown-of-thorns starfish was monitored over 7 9 days on 2 reefs of the Great Barrier Reef in 7 permanent quadrats in different depths and habitats. The pattern of decomposition was similar in all quadrats irrespective of the site or depth. Many different organisms, including crown-of-thorns starfish, fed on or scavenged the remains. Despite this activity the remains could be recognised as crown-of-thorns starfish for up to 5 days. The reason for the sudden disappearance of starfish at the ends of outbreaks is briefly discussed.

  5. Early Decomposition in Visual Word Recognition: Dissociating Morphology, Form, and Meaning

    ERIC Educational Resources Information Center

    Marslen-Wilson, William D.; Bozic, Mirjana; Randall, Billi

    2008-01-01

    The role of morphological, semantic, and form-based factors in the early stages of visual word recognition was investigated across different SOAs in a masked priming paradigm, focusing on English derivational morphology. In a first set of experiments, stimulus pairs co-varying in morphological decomposability and in semantic and orthographic…

  6. Early morphological decomposition during visual word recognition: evidence from masked transposed-letter priming.

    PubMed

    Beyersmann, Elisabeth; Castles, Anne; Coltheart, Max

    2011-10-01

    The present experiments were designed to explore the theory of early morpho-orthographic segmentation (Rastle, Davis, & New, Psychonomic Bulletin & Review 11,1090-1098, 2004), which postulates that written words with a true morphologically complex structure (cleaner) and those with a morphological pseudostructure (corner) are both decomposed into affix and stem morphemes. We used masked complex transposed-letter (TL) nonword primes in a lexical decision task. Experiment 1 replicated the well-known masked TL-priming effect using monomorphemic nonword primes (e.g., wran-WARN). Experiment 2 used the same nonword TL stems as in Experiment 1, but combined them with real suffixes (e.g., ish as in wranish-WARN). Priming was compared with that from nonsuffixed primes in which the real suffixes were replaced with nonmorphemic endings (e.g., el as in wranel-WARN). Significant priming was found in the suffixed but not in the nonsuffixed condition, suggesting that affix-stripping occurs at prelexical stages in visual word recognition and operates over early letter-position encoding mechanisms. PMID:21713371

  7. Spinodal Decomposition in a Model Colloid-Polymer Mixture in Microgravity A. E. Bailey,1,* W. C. K. Poon,2

    E-print Network

    Schofield, Andrew B.

    Spinodal Decomposition in a Model Colloid-Polymer Mixture in Microgravity A. E. Bailey,1,* W. C. K scattering and direct imaging. We observe a clear crossover from early-stage spinodal decomposition to late with molecular systems. Like molecu- lar liquids, these systems exhibit spinodal decomposition; however, while

  8. Learning by observation requires an early sleep window

    PubMed Central

    Van Der Werf, Ysbrand D.; Van Der Helm, Els; Schoonheim, Menno M.; Ridderikhoff, Arne; Van Someren, Eus J. W.

    2009-01-01

    Numerous studies have shown that sleep enhances memory for motor skills learned through practice. Motor skills can, however, also be learned through observation, a process possibly involving the mirror neuron system. We investigated whether motor skill enhancement through prior observation requires sleep to follow the observation, either immediately or after a delay, to consolidate the procedural memory. Sequence-specific fingertapping performance was tested in 64 healthy subjects in a balanced design. Electromyography verified absence of overt or subliminal hand muscle activations during observation. The results show that immediate sleep is necessary for the enhancement of a motor skill through prior observation. Immediate sleep improved the speed of subsequent performance by 22 ± 11% (mean ± SEM) (P = 0.04) and reduced the error rate by 42 ± 19% (P = 0.02). In contrast, no performance gains occurred if sleep was initiated more than 12 h after observation. A second study on 64 subjects ruled out explicit familiarity with the sequence or the spatiotemporal rhythm of the sequence to underlie performance improvements. The sleep-dependent observational motor learning enhancement is at least similar to that previously reported for implicit and declarative memory. The apparent prerequisite of observing real movements indicates that subjects transfer experience obtained through observation of movements to subsequent self-initiated movements, in the absence of practice. Moreover, the consolidation of this transfer requires an early sleep window. These findings could improve learning new motor skills in athletes and children, but also in patients having to remaster skills following stroke or injury. PMID:19884499

  9. Learning by observation requires an early sleep window.

    PubMed

    Van Der Werf, Ysbrand D; Van Der Helm, Els; Schoonheim, Menno M; Ridderikhoff, Arne; Van Someren, Eus J W

    2009-11-10

    Numerous studies have shown that sleep enhances memory for motor skills learned through practice. Motor skills can, however, also be learned through observation, a process possibly involving the mirror neuron system. We investigated whether motor skill enhancement through prior observation requires sleep to follow the observation, either immediately or after a delay, to consolidate the procedural memory. Sequence-specific fingertapping performance was tested in 64 healthy subjects in a balanced design. Electromyography verified absence of overt or subliminal hand muscle activations during observation. The results show that immediate sleep is necessary for the enhancement of a motor skill through prior observation. Immediate sleep improved the speed of subsequent performance by 22 +/- 11% (mean +/- SEM) (P = 0.04) and reduced the error rate by 42 +/- 19% (P = 0.02). In contrast, no performance gains occurred if sleep was initiated more than 12 h after observation. A second study on 64 subjects ruled out explicit familiarity with the sequence or the spatiotemporal rhythm of the sequence to underlie performance improvements. The sleep-dependent observational motor learning enhancement is at least similar to that previously reported for implicit and declarative memory. The apparent prerequisite of observing real movements indicates that subjects transfer experience obtained through observation of movements to subsequent self-initiated movements, in the absence of practice. Moreover, the consolidation of this transfer requires an early sleep window. These findings could improve learning new motor skills in athletes and children, but also in patients having to remaster skills following stroke or injury. PMID:19884499

  10. Observational evidence for AGN feedback in early-type galaxies

    E-print Network

    Kevin Schawinski; Daniel Thomas; Marc Sarzi; Claudia Maraston; Sugata Kaviraj; Seok-Joo Joo; Sukyoung K. Yi; Joseph Silk

    2007-09-19

    A major amendment in recent models of hierarchical galaxy formation is the inclusion of so-called AGN feedback. The energy input from an active central massive black hole is invoked to suppress star formation in early-type galaxies at later epochs. A major problem is that this process is poorly understood, and compelling observational evidence for its mere existence is still missing. In search for signatures of AGN feedback, we have compiled a sample of 16,000 early-type galaxies in the redshift range 0.05early-types inhabit the blue cloud, while early-types with AGN are located considerably closer to and almost on the red sequence. Star formation-AGN composites are found right between these two extremes. We further derive galaxy star formation histories using a novel method that combines multiwavelength photometry from near-UV to near-IR and stellar absorption indices. We find that in those objects deviating from the red sequence star formation occurred several 100 Myr in the past involving 1-10 per cent of the total stellar mass. We identify an evolutionary sequence from star formation via nuclear activity to quiescence. This transition process lasts about 1 Gyr, and the peak AGN phase occurs roughly half a Gyr after the starburst. The most likely interpretation is that star formation is suppressed by nuclear activity in these objects before they settle on the red sequence.

  11. Observations of hydroxyl in early-type galaxies

    E-print Network

    McBride, James; Nyland, Kristina

    2014-01-01

    We used Arecibo Observatory and the Green Bank Telescope to observe OH in twelve early-type galaxies with known reservoirs of dense gas. We present three new detections of OH in absorption in the 1667 MHz line. One objective of our survey was to find evidence of molecular outflows, but our sensitivity, and the strength of the OH absorption, were insufficient to detect outflows. The detected sources have infrared luminosities and dust temperatures among the lowest of any galaxy detected in OH absorption. The ratio $L_{\\rm HCN} / L_{\\rm CO}$, a measure of the dense gas fraction in galaxies, is a powerful selector of OH megamasers for galaxies with high infrared luminosity. In early-type galaxies, which have much lower infrared luminosities, $L_{\\rm HCN} / L_{\\rm CO}$ is also a promising tool for discovering OH, but in absorption rather than in maser emission. In addition to dense molecular gas, a radio continuum source and a favorable line-of-sight to the observer are likely key factors in detecting OH absorber...

  12. "Learning Stories"--Crossing Borders: Introducing Qualitative Early Childhood Observation Techniques to Early Childhood Practitioners in Saudi Arabia

    ERIC Educational Resources Information Center

    Nyland, Berenice; Alfayez, Shatha

    2012-01-01

    Early childhood education has become a focus of government policy across the world. Part of the present increased interest in early childhood education has been a focus on curriculum frameworks and socio/cultural methods of assessment. Currently, New Zealand has emerged as a world leader in early childhood education, and observation and assessment…

  13. A longitudinal observation of early pulmonary responses to cotton dust

    PubMed Central

    Wang, X; Pan, L; Zhang, H; Sun, B; Dai, H; Christiani, D

    2003-01-01

    Aims: To examine early adverse pulmonary effects of exposure to cotton dust, and to identify potential risk factors, including atopy for pulmonary responses to cotton dust. Methods: Spirometry, methacholine challenge testing, and questionnaire; performed among 101 non-smoking newly hired textile workers at baseline (prior to starting work), and at 3, 12, and 18 months after starting work. Concentrations of airborne cotton dust in various work areas were measured at each follow up survey using vertical elutriators. Results: The incidence of non-specific respiratory symptoms was 8% at three months, then diminished afterwards. Substantial acute cross shift drops in FEV1 at each follow up survey, and longitudinal declines in FVC and FEV1 after 12 months of exposure were observed. Airway responsiveness to methacholine increased with follow up time, and was more pronounced among atopics. Increasing airway responsiveness was strongly correlated with cross shift drops in FEV1. In addition, one or more respiratory symptoms at three months was significantly, and pre-existing atopy marginally significantly, associated with cross shift drops in FEV1 after adjusting for other covariates and confounders. Conclusion: Results suggest that non-specific respiratory symptoms, decreasing lung function, and increasing airway responsiveness are early pulmonary responses to cotton dust. In addition, the occurrence of respiratory symptoms and increasing airway responsiveness, as well as atopy, may be important predictors for acute changes in lung function among cotton textile workers. PMID:12554839

  14. TEMPORAL SIGNATURES OF AIR QUALITY OBSERVATIONS AND MODEL OUTPUTS: DO TIME SERIES DECOMPOSITION METHODS CAPTURE RELEVANT TIME SCALES?

    EPA Science Inventory

    Time series decomposition methods were applied to meteorological and air quality data and their numerical model estimates. Decomposition techniques express a time series as the sum of a small number of independent modes which hypothetically represent identifiable forcings, thereb...

  15. Early Hinode Observations of a Solar Filament Eruption

    NASA Technical Reports Server (NTRS)

    Sterling, Alphonse C.; Moore, Ronald L.

    2007-01-01

    We use Hinode X-Ray Telescope (XRT) and Solar Optical Telescope (SOT) filtergraph (FG) Stokes-V magnetogram observations to study the early onset of a solar eruption that includes an erupting filament that we observe in TRACE EUV images; this is one of the first filament eruptions seen with Hinode. The filament undergoes a slow rise for at least 30 min prior to its fast eruption and strong soft X-ray flaring, and the new Hinode data elucidate the physical processes occurring during the slow-rise period: During the slow-rise phase, a soft X-ray (SXR) sigmoid forms from apparent reconnection low in the sheared core field traced by the filament, and there is a low-level intensity peak in both EUV and SXRs during the slow rise. The SOT data show that magnetic flux cancellation occurs along the neutral line of the filament in the hours before eruption, and this likely caused the low-lying reconnection that produced the microflaring and the slow rise leading up to the eruption.

  16. Spectral Models for Early Time SN 2011fe Observations

    E-print Network

    Baron, E; Sullivan, M; Hsiao, E; Ellis, R S; Gal-Yam, A; Howell, D A; Nugent, P E; Dominguez, I; Krisciunas, K; Phillips, M M; Suntzeff, N; Wang, L; Thomas, R C

    2015-01-01

    We use observed UV through near IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal SNe Ia and to examine its individual peculiarities. As a benchmark, we use a delayed-detonation model with a progenitor metallicity of Z_solar/20. We study the sensitivity of features to variations in progenitor metallicity, the outer density profile, and the distribution of radioactive nickel. The effect of metallicity variations in the progenitor have a relatively small effect on the synthetic spectra. We also find that the abundance stratification of SN 2011fe resembles closely that of a delayed detonation model with a transition density that has been fit to other Branch-normal Type Ia supernovae. At early times, the model photosphere is formed in material with velocities that are too high, indicating that the photosphere recedes too slowly or that SN 2011fe has a lower specific energy in the outer ~0.1 M_sun than does the model. We discuss several explanations for the discrepancies. ...

  17. Spectral models for early time SN 2011fe observations

    NASA Astrophysics Data System (ADS)

    Baron, E.; Hoeflich, P.; Friesen, Brian; Sullivan, M.; Hsiao, E.; Ellis, R. S.; Gal-Yam, A.; Howell, D. A.; Nugent, P. E.; Dominguez, I.; Krisciunas, K.; Phillips, M. M.; Suntzeff, N.; Wang, L.; Thomas, R. C.

    2015-12-01

    We use observed UV through near-IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal Type Ia supernovae (SNe Ia) and to examine its individual peculiarities. As a benchmark, we use a delayed-detonation model with a progenitor metallicity of Z?/20. We study the sensitivity of features to variations in progenitor metallicity, the outer density profile, and the distribution of radioactive nickel. The effect of metallicity variations in the progenitor have a relatively small effect on the synthetic spectra. We also find that the abundance stratification of SN 2011fe resembles closely that of a delayed-detonation model with a transition density that has been fit to other Branch-normal SNe Ia. At early times, the model photosphere is formed in material with velocities that are too high, indicating that the photosphere recedes too slowly or that SN 2011fe has a lower specific energy in the outer ?0.1 M? than does the model. We discuss several explanations for the discrepancies. Finally, we examine variations in both the spectral energy distribution and in the colours due to variations in the progenitor metallicity, which suggests that colours are only weak indicators for the progenitor metallicity, in the particular explosion model that we have studied. We do find that the flux in the U band is significantly higher at maximum light in the solar metallicity model than in the lower metallicity model and the lower metallicity model much better matches the observed spectrum.

  18. No Differences in Decomposition Rates observed between Bacillus thuringiensis and Non-Bacillus thuringiensis Corn Residue Incubated in the Field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent speculation of slower residue decomposition for Bt corn hybrids compared to non-Bt corn hybrids has prompted investigative study. We evaluated the residue decomposition rates of Bt and non-Bt corn hybrids over a period of 22 months under field conditions using the litter bag technique. The ...

  19. Imaging chemical concentration pattern and early stages of spinodal decomposition in the Ag x Na1?x Br system by scanning force microscopy

    NASA Astrophysics Data System (ADS)

    Güthoff, F.; Zhang, B.; Eckold, G.

    2015-10-01

    In quasi binary systems like AgBr–NaBr the demixing from the homogeneous high temperature phase into separated phases is a complex process that depends on the ageing temperature as well as on the quench rate. Spinodal decomposition and nucleation processes can be distinguished which lead, however, to the same final equilibrium state. Using frequency modulated scanning force microscopy we aimed to distinguish the demixed phases and their morphologies on a nm-scale at room temperature for samples with different concentration. While no contrast between the different phases are observed in the usual topographic mode, a modified evaluation of Kelvin experiments allows the distinction of silver- and sodium enriched phases. Moreover, direct evidence is found for concentration fluctuations which are characteristic for spinodal decomposition.

  20. The Swift XRT: Observations of Early X-ray Afterglows

    SciTech Connect

    Burrows, David N.; Kennea, J. A.; Nousek, J. A.; Osborne, J. P.; O'Brien, P. T.; Chincarini, G.; Tagliaferri, G.; Giommi, P.; Zhang, B.

    2006-05-19

    During the first year of operations of the Swift observatory, the X-ray Telescope has made a number of discoveries concerning the nature of X-ray afterglows of both long and short GRBs. We highlight the key findings, which include rapid declines at early times, a standard template of afterglow light curve shapes, common flaring, and the discovery of the first short GRB afterglow.

  1. An Observational Study of the Interactions of Socially Withdrawn/Anxious Early Adolescents and Their Friends

    ERIC Educational Resources Information Center

    Schneider, Barry H.

    2009-01-01

    Background: The friendships of socially withdrawn/anxious children and early adolescents have been found to lack critical rewarding qualities. Observational research may help elucidate the obstacles they face in forming and maintaining high-quality friendships with sociable peers. Method: We observed the interactions of 38 socially withdrawn early

  2. Determining the progenitors of supernovae with early robotic observations

    NASA Astrophysics Data System (ADS)

    Howell, Andrew

    2015-08-01

    We present results from the LCOGT Supernova Key Project, a three year program to obtain lightcurves and spectra of 600 supernovae. The Las Cumbres Observatory Global Telescope Network is a network of eleven robotic 1m and 2m telescopes located at 5 sites around the world. With this facility long term monitoring of transient phenomena is possible, as are nearly instantaneous observations. We report on both core-collapse and thermonuclear supernovae observed within days of explosion, allowing insight into their progenitor stars.

  3. Computing Cylindrical Algebraic Decomposition via Triangular Decomposition

    E-print Network

    Moreno Maza, Marc

    Computing Cylindrical Algebraic Decomposition via Triangular Decomposition Changbo Chen, Marc Cylindrical algebraic decomposition (CAD) is a fundamental tool in real algebraic geometry. It was introduced polynomial arithmetic, being developed for triangular decompositions. #12;Cylindrical Algebraic Decomposition

  4. Basin-scale, integrated observations of the early 21st century multiyear drought

    E-print Network

    Tregoning, Paul

    Basin-scale, integrated observations of the early 21st century multiyear drought in southeast] The Murray-Darling Basin in southeast Australia is experiencing one of the most severe droughts observed. This paper provides new basin-scale observations of the multiyear drought, integrated to a degree rarely

  5. Adhesive Small Bowel Obstruction: Early Operative versus Observational Management.

    PubMed

    Bauer, Joel; Keeley, Brieze; Krieger, Beth; Deliz, Juan; Wallace, Kojo; Kruse, Danielle; Dallas, Kai; Bornstein, Joseph; Chessin, David; Gorfine, Stephen

    2015-06-01

    We assessed the nonoperative and operative management of adhesive small bowel obstruction (ASBO) and compared complication rates and surgical outcomes. ASBO is a common complication of abdominopelvic surgery. Although patients may respond to nonoperative management, many require surgery. We retrospectively studied patients admitted to Mount Sinai Hospital with a diagnosis of complete ASBO to determine outcomes of nonoperative management. Patients admitted with complete ASBO from 2001 to 2011 were included. Patients with no previous abdominopelvic surgery, surgery within the six weeks preceding admission and obstruction due to other identifiable causes, such as incarcerated hernia, were excluded. Complication rates and outcomes were compared between patients managed with immediate surgery and those managed initially with nonoperative strategies. Of 460 patients admitted with complete ASBO, 106 (23.0%) had surgery within 24 hours of admission. At surgery, 20 (18.9%) had ischemic bowel and 8 (7.5%) had perforations. The remaining 354 patients had a trial of nonoperative management lasting at least 24 hours. Of 354 patients managed initially without surgery, 100 (28.2%) patients were discharged without operative intervention during their index admissions. Among the patients having surgery more than 24 hours after admission, indications for surgery were generally failure to resolve, worsening clinical status, and change in imaging findings. Of those patients observed for at least 24 hours, 40 (15.7%) were found to have ischemic bowel and 5 (2.0%) had perforation at surgery. Rates of bowel resection, stoma creation and postoperative complications were similar for the immediate and delayed surgery groups. Among the delayed surgery group, 71 (28.0%) required a bowel resection and 11 (4.3%) stoma creation. Twenty one per cent had postoperative complications, most commonly ileus. There were no statistically significant differences in the outcomes between immediate and delayed groups regardless of duration of delay. Among patients observed with complete ASBO, 24.6 per cent of patients with adhesive obstruction resolved without surgery or readmission. Delaying operative management did not affect surgical findings or complication rates. PMID:26031276

  6. Photochemical decomposition of energetic materials: Observation of aryl benzyloxy nitroxide and aryl benzyl nitroxide radicals in solutions of 1,3,5-trinitrobenzene and toluene and their deuteriated analogues at 200 K

    SciTech Connect

    Menapace, J.A.; Marlin, J.E. )

    1990-03-08

    Electron spin resonance spectroscopy is used to probe the photodecomposition of 1,3,5-trinitrobenzene (TNB) in toluene. The photodecomposition is conducted at 200 K with solutions containing TNB and toluene along with solutions containing their deuteriated analogues. primary radicals observed in the decomposition have structures consistent with 3,5-dinitrophenyl benzyloxy nitroxide moieties. These radicals are proposed to be precursors to 3,5-dinitrophenyl benzyl nitroxide radicals previously observed in both photochemical and thermal decomposition.

  7. A Validation of the Early Childhood Classroom Observation Measure in Finnish and Estonian Kindergartens

    ERIC Educational Resources Information Center

    Lerkkanen, Marja-Kristiina; Kikas, Eve; Pakarinen, Eija; Trossmann, Kaili; Poikkeus, Anna-Maija; Rasku-Puttonen, Helena; Siekkinen, Martti; Nurmi, Jari-Erik

    2012-01-01

    Research Findings: The aim of the study was to examine the applicability and psychometric properties of the Early Childhood Classroom Observation Measure (ECCOM; D. J. Stipek & P. Byler, 2005) outside the United States. The ECCOM was used to observe 83 kindergarten teachers (49 in Finland and 34 in Estonia) in classroom situations. Self-ratings…

  8. Direct Extraction of Tumor Response Based on Ensemble Empirical Mode Decomposition for Image Reconstruction of Early Breast Cancer Detection by UWB.

    PubMed

    Li, Qinwei; Xiao, Xia; Wang, Liang; Song, Hang; Kono, Hayato; Liu, Peifang; Lu, Hong; Kikkawa, Takamaro

    2015-10-01

    A direct extraction method of tumor response based on ensemble empirical mode decomposition (EEMD) is proposed for early breast cancer detection by ultra-wide band (UWB) microwave imaging. With this approach, the image reconstruction for the tumor detection can be realized with only extracted signals from as-detected waveforms. The calibration process executed in the previous research for obtaining reference waveforms which stand for signals detected from the tumor-free model is not required. The correctness of the method is testified by successfully detecting a 4 mm tumor located inside the glandular region in one breast model and by the model located at the interface between the gland and the fat, respectively. The reliability of the method is checked by distinguishing a tumor buried in the glandular tissue whose dielectric constant is 35. The feasibility of the method is confirmed by showing the correct tumor information in both simulation results and experimental results for the realistic 3-D printed breast phantom. PMID:26552095

  9. Observations of Glide and Decomposition of a<101> Dislocations at High Temperatures in Ni-Al Single Crystals Deformed along the Hard Orientation

    NASA Technical Reports Server (NTRS)

    Srinivasan, R.; Daw, M. S.; Noebe, R. D.; Mills, M. J.

    2003-01-01

    Ni-44at.% Al and Ni-50at.% single crystals were tested in compression in the hard (001) orientations. The dislocation processes and deformation behavior were studied as a function of temperature, strain and strain rate. A slip transition in NiAl occurs from alpha(111) slip to non-alphaaaaaaaaaaa9111) slip at intermediate temperatures. In Ni-50at.% Al single crystal, only alpha(010) dislocations are observed above the slip transition temperature. In contrast, alpha(101)(101) glide has been observed to control deformation beyond the slip transition temperature in Ni-44at.%Al. alpha(101) dislocations are observed primarily along both (111) directions in the glide plane. High-resolution transmission electron microscopy observations show that the core of the alpha(101) dislocations along these directions is decomposed into two alpha(010) dislocations, separated by a distance of approximately 2nm. The temperature window of stability for these alpha(101) dislocations depends upon the strain rate. At a strain rate of 1.4 x 10(exp -4)/s, lpha(101) dislocations are observed between 800 and 1000K. Complete decomposition of a alpha(101) dislocations into alpha(010) dislocations occurs beyond 1000K, leading to alpha(010) climb as the deformation mode at higher temperature. At lower strain rates, decomposition of a alpha(101) dislocations has been observed to occur along the edge orientation at temperatures below 1000K. Embedded-atom method calculations and experimental results indicate that alpha(101) dislocation have a large Peieris stress at low temperature. Based on the present microstructural observations and a survey of the literature with respect to vacancy content and diffusion in NiAl, a model is proposed for alpha(101)(101) glide in Ni-44at.%Al, and for the observed yield strength versus temperature behavior of Ni-Al alloys at intermediate and high temperatures.

  10. Ozone decomposition

    PubMed Central

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho

    2014-01-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates. PMID:26109880

  11. Naturalistic Observations of Schoolyard Social Participation: Marker Variables for Socio-Emotional Functioning in Early Adolescence

    ERIC Educational Resources Information Center

    Coplan, Robert J.; Ooi, Laura L.; Rose-Krasnor, Linda

    2015-01-01

    The goal of this study was to examine links between observed social participation in the schoolyard and indices of socio-emotional functioning in early adolescence. Participants were children (N = 290) aged 9 to 12 years. Social participation (e.g., solitary play, dyadic interaction, group interaction) was assessed in the schoolyard during recess…

  12. LABORATORY OBSERVATIONS ON THE EARLY GROWTH OF THE ABALONE, HALIOTIS SORENSENI, AND THE EFFECT OF TEMPERATURE

    E-print Network

    was observed at lOoC. Juveniles maintained at 15-19°C and provided mixed diatoms as food showed marked- berculata Linnaeus were given by Crofts (1929, 1937). Japanese workers have reported obser- vations on early more critical studies of growth and nutrition of abalones. Advances by Japanese workers in the fie

  13. Probing the interstellar medium in early-type galaxies with Infrared Space Oberservatory observations

    NASA Technical Reports Server (NTRS)

    Malhotra, S.; Hollenbach, D.; Helou, D.; Silbermann, N.; Valjavec, E.; Rubin, R.; Dale, D.; Hunter, D.; Lu, N.; Lord, S.; Dinerstein, H.; Thronson, H.

    2000-01-01

    Four IRAS-detected early-type galaxies were observed with the Infrared Space Observatory (ISO). With the exception of the 15 mu m image of NGC 1052, the mid-IR images of NGC 1052, NGC 1155, NGC 5866, and NGC 6958 at 4.5, 7, and 15 mu m show extended emission.

  14. VOLUME 78, NUMBER 14 P H Y S I C A L R E V I E W L E T T E R S 7 APRIL 1997 X-ray Scattering Study of Early Stage Spinodal Decomposition in Al0.62Zn0.38

    E-print Network

    Elder, Ken

    of Early Stage Spinodal Decomposition in Al0.62Zn0.38 J. Mainville,* Y. S. Yang, K. R. Elder, and M. Sutton of equilibrium thermo- dynamics to provide the "driving force" for the transition. A quantitative comparison

  15. Thermal Decomposition of IMX-104: Ingredient Interactions Govern Thermal Insensitivity

    SciTech Connect

    Maharrey, Sean; Wiese-Smith, Deneille; Highley, Aaron M.; Steill, Jeffrey D.; Behrens, Richard; Kay, Jeffrey J.

    2015-04-01

    This report summarizes initial studies into the chemical basis of the thermal insensitivity of INMX-104. The work follows upon similar efforts investigating this behavior for another DNAN-based insensitive explosive, IMX-101. The experiments described demonstrate a clear similarity between the ingredient interactions that were shown to lead to the thermal insensitivity observed in IMX-101 and those that are active in IMX-104 at elevated temperatures. Specifically, the onset of decomposition of RDX is shifted to a lower temperature based on the interaction of the RDX with liquid DNAN. This early onset of decomposition dissipates some stored energy that is then unavailable for a delayed, more violent release.

  16. Decomposition techniques

    USGS Publications Warehouse

    Chao, T.T.; Sanzolone, R.F.

    1992-01-01

    Sample decomposition is a fundamental and integral step in the procedure of geochemical analysis. It is often the limiting factor to sample throughput, especially with the recent application of the fast and modern multi-element measurement instrumentation. The complexity of geological materials makes it necessary to choose the sample decomposition technique that is compatible with the specific objective of the analysis. When selecting a decomposition technique, consideration should be given to the chemical and mineralogical characteristics of the sample, elements to be determined, precision and accuracy requirements, sample throughput, technical capability of personnel, and time constraints. This paper addresses these concerns and discusses the attributes and limitations of many techniques of sample decomposition along with examples of their application to geochemical analysis. The chemical properties of reagents as to their function as decomposition agents are also reviewed. The section on acid dissolution techniques addresses the various inorganic acids that are used individually or in combination in both open and closed systems. Fluxes used in sample fusion are discussed. The promising microwave-oven technology and the emerging field of automation are also examined. A section on applications highlights the use of decomposition techniques for the determination of Au, platinum group elements (PGEs), Hg, U, hydride-forming elements, rare earth elements (REEs), and multi-elements in geological materials. Partial dissolution techniques used for geochemical exploration which have been treated in detail elsewhere are not discussed here; nor are fire-assaying for noble metals and decomposition techniques for X-ray fluorescence or nuclear methods be discussed. ?? 1992.

  17. Observing the Cosmic Microwave Background Radiation: A Unique Window on the Early Universe

    NASA Technical Reports Server (NTRS)

    Hinshaw, Gary; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    The cosmic microwave background radiation is the remnant heat from the Big Bang. It provides us with a unique probe of conditions in the early universe, long before any organized structures had yet formed. The anisotropy in the radiation's brightness yields important clues about primordial structure and additionally provides a wealth of information about the physics,of the early universe. Within the framework of inflationary dark matter models observations of the anisotropy on sub-degree angular scales will reveal the signatures of acoustic oscillations of the photon-baryon fluid at a redshift of approx. 1100. The validity of inflationary models will be tested and, if agreement is found, accurate values for most of the key cosmological parameters will result. If disagreement is found, we will need to rethink our basic ideas about the physics of the early universe. I will present an overview of the physical processes at work in forming the anisotropy and discuss what we have already learned from current observations. I will conclude with a brief overview of the recently launched Microwave Anisotropy Probe (MAP) mission which will observe the anisotropy over the full sky with 0.21 degree angular resolution. At the time of this meeting, MAP will have just arrived at the L2 Lagrange point, marking the start of its observing campaign. The MAP hardware is being produced by Goddard in partnership with Princeton University.

  18. Observational Constraints on the Nature of the First Supermassive Black Holes Seeds in the Early Universe

    NASA Astrophysics Data System (ADS)

    Treister, Ezequiel; Schawinski, Kevin; Natarajan, Priyamvada; Weigel, Anna

    2015-08-01

    We constrain the total accreted mass density in supermassive black holes at z>6, as inferred from the integrated X-ray emission in a sample of galaxy candidates selected using observed-frame optical and near-IR dropout techniques. Combining galaxy samples acquired in the Hubble Ultra Deep Field with recent deep Hubble observations of the CANDELS fields and Chandra 4 Msec observations we obtain the most restrictive current constraints on total black hole growth in the early Universe, estimating a mass density <1000M?Mpc-3. We further carry out a detailed study of all the individually-detected X-ray sources in the Chandra Deep Field South, finding that none of them is a good candidate to be at z>5.These results place interesting constraints on growth by accretion and imply one or more of the following: only ~20% luminous galaxies at this epoch are seeded with BHs - so seeding is inefficient; most black hole growth at early epochs happens in dusty - as yet undetected - host galaxies and/or in less-massive - also as yet undetected - galaxies; therefore a large fraction of the early black hole buildup is heavily obscured or that either most of the growth is due to radiatively inefficient accretion or due to black hole mergers at these early times. Not seeing a signal from growing black holes in high-redshift galaxies suggests that if their black holes are growing they are doing so in a veiled fashion, or they are simply not growing or perhaps most galaxies do not harbor black holes at their centers at all. These possibilities offer novel insights for high redshift seed formation models.Finally, we present the prospects to constrain the nature of the first black hole seeds in the early Universe using existing and planned space-based facilities.

  19. ROSAT PSPC observation of the X-ray faint early-type galaxy NGC5866

    E-print Network

    S. Pellegrini

    1994-07-03

    We present the results of the analysis of the ROSAT PSPC pointed observation of the S0 galaxy NGC5866. Previous Einstein observations had revealed that this galaxy has a low X-ray to optical ratio Lx/Lb. Theoretical models of the X-ra emission of early-type galaxies had suggested that in objects of this kind the emission is not dominated by the presence of a hot diffuse gas, but should originate in stellar sources. We discuss the evidence in favor of this hypothesis following from the results of the analysis of the ROSAT PSPC data. The X-ray spectrum shows properties similar to those of the other two low Lx/Lb early-type galaxies observed by ROSAT so far, including the presence of very soft emission. So, these galaxies can be recognized as a group with homogeneous properties, and a more exhaustive picture of the nature of the X-ray emission across the Lx/Lb plane of early-type galaxies can be outlined. We also discuss the importance of rotation in the X-ray emission of S0 galaxies, and suggest that it could explain why on average S0s are less X-ray luminous than ellipticals.

  20. Woodland Decomposition.

    ERIC Educational Resources Information Center

    Napier, J.

    1988-01-01

    Outlines the role of the main organisms involved in woodland decomposition and discusses some of the variables affecting the rate of nutrient cycling. Suggests practical work that may be of value to high school students either as standard practice or long-term projects. (CW)

  1. Sector Decomposition

    E-print Network

    Gudrun Heinrich

    2008-05-16

    Sector decomposition is a constructive method to isolate divergences from parameter integrals occurring in perturbative quantum field theory. We explain the general algorithm in detail and review its application to multi-loop Feynman parameter integrals as well as infrared divergent phase-space integrals over real radiation matrix elements.

  2. Overlooked sunspot observations by Hevelius in the early Maunder Minimum, 1653 1684

    NASA Astrophysics Data System (ADS)

    Hoyt, Douglas V.; Schatten, Kenneth H.

    1995-09-01

    In the bookMachina Coelestis (1679), Johannes Hevelius lists his daily solar observations from 1653 to 1679. He mentions 19 sunspot groups during this interval, of which 14 are unique to Hevelius and five are confirmed by other observers. There are an additional 9 sunspot groups during this interval that were not observed by Hevelius. In five cases he was not observing, but in the other four cases he did observe but failed to comment upon sunspots. The spots he missed or failed to observe tend to occur near the end of his career. This suggests Hevelius occasionally missed sunspots but usually was a reliable observer. These observations are important because they provide us the only known daily listing of solar observations during the early years of the Maunder Minimum. They are also important because they were overlooked by Wolf, Spoerer, Maunder, Eddy, and others in their study of solar activity in the seventeenth century. They provide us the best record of the sunspot maximum of 1660 when one sunspot lasted at least 86 days as it traversed the solar disk four times. The same region was active for seven solar rotations.

  3. Towards Characterizing Early-stage SEP Fluxes with High-Cadence EUV Coronal Shock Observations

    NASA Astrophysics Data System (ADS)

    Kozarev, Kamen A.; Raymond, John C.; Hammer, Michael

    2014-06-01

    Recent advances in space-based solar observing have enabled unprecedented access to high-cadence, high-resolution observations of the coronal dynamics. This is extremely important, since transient phenomena in the corona usually cover multiple scales - from the current spatial resolution limit in the case of reconnection, to several solar radii in the case of coronal waves and mass ejections. The latter are also thought to drive shocks in the corona, which in turn have been shown capable of accelerating protons, electrons, and other species up to GeV energies in a matter of tens of minutes. These solar energetic particles (SEPs) are a prime source of space weather. Historically, it has been notoriously difficult to extract information about energetic particle spectra in the corona, due to the lack of in situ measurements. It is possible, however, to use remote observations in order to deduce coronal shock dynamics and related particle spectra, with some reasonable assumptions. We present an effort towards building a framework for estimating coronal SEP spectra in the early stages of real CME events, based on a combination of fast-cadence extreme ultraviolet imaging (from the SDO/AIA instrument), potential coronal magnetic field models, and differential emission measure models. The ultimate goal for this framework is to give predictions for early-stage SEP spectra for various source populations and coronal turbulence levels. It is designed in a modular fashion, and may be adapted for near real time use. This system can be applied for early warning and predicting the severity of the impulsive early stages of SEP events.

  4. [Observations of play and verbal behavior of boys with fragile X syndrome in early childhood].

    PubMed

    Sarimski, K

    1999-08-01

    Reports on development and behaviour in boys with fragile-X syndrome support the idea of a characteristic behavioural phenotype in this special population. Preliminary results are presented for 10 boys with fragile-X syndrome in early childhood. Severe mental handicaps and communicative abnormalities are observed less frequently than was expected on the basis of results reported for school-age children or adults. Boys with fragile-X syndrome show goal-directed and cooperative play behaviours in a Montessori play session, but less persistence and organisation than children with normal development or a mental handicap of heterogeneous origin. Results confirmed these behavioural differences as characteristic aspects of a "behavioural phenotype" in children who already in early childhood have fragile-X syndrome. PMID:10478436

  5. Constraining the temperature history of the past millennium using early instrumental observations

    NASA Astrophysics Data System (ADS)

    Brohan, P.

    2012-12-01

    The current assessment that twentieth-century global temperature change is unusual in the context of the last thousand years relies on estimates of temperature changes from natural proxies (tree-rings, ice-cores etc.) and climate model simulations. Confidence in such estimates is limited by difficulties in calibrating the proxies and systematic differences between proxy reconstructions and model simulations - notable differences include large differences in multi-decadal variability between proxy reconstructions, and big uncertainties in the effect of volcanic eruptions. Because the difference between the estimates extends into the relatively recent period of the early nineteenth century it is possible to compare them with a reliable instrumental estimate of the temperature change over that period, provided that enough early thermometer observations, covering a wide enough expanse of the world, can be collected. By constraining key aspects of the reconstructions and simulations, instrumental observations, inevitably from a limited period, can reduce reconstruction uncertainty throughout the millennium. A considerable quantity of early instrumental observations are preserved in the world's archives. One organisation which systematically made observations and collected the results was the English East-India Company (EEIC), and 900 log-books of EEIC ships containing daily instrumental measurements of temperature and pressure have been preserved in the British Library. Similar records from voyages of exploration and scientific investigation are preserved in published literature and the records in National Archives. Some of these records have been extracted and digitised, providing hundreds of thousands of new weather records offering an unprecedentedly detailed view of the weather and climate of the late eighteenth and early nineteenth centuries. The new thermometer observations demonstrate that the large-scale temperature response to the Tambora eruption and the 1809 eruption was modest (perhaps 0.5C). This provides a powerful out-of-sample validation for the proxy reconstructions --- supporting their use for longer-term climate reconstructions. However, some of the climate model simulations in the CMIP5 ensemble show much larger volcanic effects than this --- such simulations are unlikely to be accurate in this respect.

  6. Computing Cylindrical Algebraic Decomposition via Triangular Decomposition

    E-print Network

    Moreno Maza, Marc

    Computing Cylindrical Algebraic Decomposition via Triangular Decomposition Changbo Chen ORCCA of Trustworthy Computing East China Normal University, Shanghai, China lyang@sei.ecnu.edu.cn ABSTRACT Cylindrical decomposition in order to obtain an F-invariant cylindrical decomposition of the n-dimensional complex space

  7. Unifying two Graph Decompositions with Modular Decomposition

    E-print Network

    Fondements et Applications, Université Paris 7

    Unifying two Graph Decompositions with Modular Decomposition Binh-Minh Bui-Xuan1 , Michel Habib2, tournaments, digraphs, and 2-structures. We show that, under some axioms, a unique decomposition tree exists computation, and decomposition tree computation when the tree exists. Our results unify many known

  8. Interactions of tissue and fertilizer nitrogen on decomposition dynamics of lignin-rich conifer litter

    USGS Publications Warehouse

    Perakis, Steven S.; Matkins, Joselin J.; Hibbs, David E.

    2012-01-01

    High tissue nitrogen (N) accelerates decomposition of high-quality leaf litter in the early phases of mass loss, but the influence of initial tissue N variation on the decomposition of lignin-rich litter is less resolved. Because environmental changes such as atmospheric N deposition and elevated CO2 can alter tissue N levels within species more rapidly than they alter the species composition of ecosystems, it is important to consider how within-species variation in tissue N may shape litter decomposition and associated N dynamics. Douglas-fir (Pseudotsuga menziesii ) is a widespread lignin-rich conifer that dominates forests of high carbon (C) storage across western North America, and displays wide variation in tissue and litter N that reflects landscape variation in soil N. We collected eight unique Douglas-fir litter sources that spanned a two-fold range in initial N concentrations (0.67–1.31%) with a narrow range of lignin (29–35%), and examined relationships between initial litter chemistry, decomposition, and N dynamics in both ambient and N fertilized plots at four sites over 3 yr. High initial litter N slowed decomposition rates in both early (0.67 yr) and late (3 yr) stages in unfertilized plots. Applications of N fertilizer to litters accelerated early-stage decomposition, but slowed late-stage decomposition, and most strongly affected low-N litters, which equalized decomposition rates across litters regardless of initial N concentrations. Decomposition of N-fertilized litters correlated positively with initial litter manganese (Mn) concentrations, with litter Mn variation reflecting faster turnover of canopy foliage in high N sites, producing younger litterfall with high N and low Mn. Although both internal and external N inhibited decomposition at 3 yr, most litters exhibited net N immobilization, with strongest immobilization in low-N litter and in N-fertilized plots. Our observation for lignin-rich litter that high initial N can slow decomposition yet accelerate N release differs from findings where litter quality variation across species promotes coupled C and N release during decomposition. We suggest reevaluation of ecosystem models and projected global change effects to account for a potential decoupling of ecosystem C and N feedbacks through litter decomposition in lignin-rich conifer forests.

  9. On the observation of mesospheric air inside the arctic stratospheric polar vortex in early 2003

    NASA Astrophysics Data System (ADS)

    Engel, A.; Möbius, T.; Haase, H.-P.; Bönisch, H.; Wetter, T.; Schmidt, U.; Levin, I.; Reddmann, T.; Oelhaf, H.; Wetzel, G.; Grunow, K.; Huret, N.; Pirre, M.

    2005-08-01

    During several balloon flights inside the Arctic polar vortex in early 2003, unusual trace gas distributions were observed, which indicate a strong influence of mesospheric air in the stratosphere. The tuneable diode laser (TDL) instrument SPIRALE (Spectroscopie InFrarouge par Absorption de Lasers Embarqués) measured unusually high CO values (up to 600 ppb) on 27 January at about 30 km altitude. The cryosampler BONBON sampled air masses with very high molecular Hydrogen, extremely low SF6 and enhanced CO values on 6 March at about 25 km altitude. Finally, the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) Fourier Transform Infra-Red (FTIR) spectrometer showed NOy values which are significantly higher than NOy* (the NOy derived from a correlation between N2O and NOy under undisturbed conditions), on 21 and 22 March in a layer centred at 22 km altitude. Thus, the mesospheric air seems to have been present in a layer descending from about 30 km in late January to 25 km altitude in early March and about 22 km altitude on 20 March. We present corroborating evidence from a model study using the KASIMA (KArlsruhe Simulation model of the Middle Atmosphere) model that also shows a layer of mesospheric air, which descended into the stratosphere in November and early December 2002, before the minor warming which occurred in late December 2002 lead to a descent of upper stratospheric air, cutting of a layer in which mesospheric air is present. This layer then descended inside the vortex over the course of the winter. The same feature is found in trajectory calculations, based on a large number of trajectories started in the vicinity of the observations on 6 March. Based on the difference between the mean age derived from SF6 (which has an irreversible mesospheric loss) and from CO2 (whose mesospheric loss is much smaller and reversible) we estimate that the fraction of mesospheric air in the layer observed on 6 March, must have been somewhere between 35% and 100%.

  10. Observation of mesospheric air inside the arctic stratospheric polar vortex in early 2003

    NASA Astrophysics Data System (ADS)

    Engel, A.; Möbius, T.; Haase, H.-P.; Bönisch, H.; Wetter, T.; Schmidt, U.; Levin, I.; Reddmann, T.; Oelhaf, H.; Wetzel, G.; Grunow, K.; Huret, N.; Pirre, M.

    2006-02-01

    During several balloon flights inside the Arctic polar vortex in early 2003, unusual trace gas distributions were observed, which indicate a strong influence of mesospheric air in the stratosphere. The tuneable diode laser (TDL) instrument SPIRALE (Spectroscopie Infra-Rouge par Absorption de Lasers Embarqués) measured unusually high CO values (up to 600 ppb) on 27 January at about 30 km altitude. The cryosampler BONBON sampled air masses with very high molecular Hydrogen, extremely low SF6 and enhanced CO values on 6 March at about 25 km altitude. Finally, the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) Fourier Transform Infra-Red (FTIR) spectrometer showed NOy values which are significantly higher than NOy* (the NOy derived from a correlation between N2O and NOy under undisturbed conditions), on 21 and 22 March in a layer centred at 22 km altitude. Thus, the mesospheric air seems to have been present in a layer descending from about 30 km in late January to 25 km altitude in early March and about 22 km altitude on 20 March. We present corroborating evidence from a model study using the KASIMA (KArlsruhe SImulation model of the Middle Atmosphere) model that also shows a layer of mesospheric air, which descended into the stratosphere in November and early December 2002, before the minor warming which occurred in late December 2002 lead to a descent of upper stratospheric air, cutting off a layer in which mesospheric air is present. This layer then descended inside the vortex over the course of the winter. The same feature is found in trajectory calculations, based on a large number of trajectories started in the vicinity of the observations on 6 March. Based on the difference between the mean age derived from SF6 (which has an irreversible mesospheric loss) and from CO2 (whose mesospheric loss is much smaller and reversible) we estimate that the fraction of mesospheric air in the layer observed on 6 March, must have been somewhere between 35% and 100%.

  11. Constraining the temperature history of the past millennium using early instrumental observations

    NASA Astrophysics Data System (ADS)

    Brohan, P.; Allan, R.; Freeman, E.; Wheeler, D.; Wilkinson, C.; Williamson, F.

    2012-10-01

    The current assessment that twentieth-century global temperature change is unusual in the context of the last thousand years relies on estimates of temperature changes from natural proxies (tree-rings, ice-cores, etc.) and climate model simulations. Confidence in such estimates is limited by difficulties in calibrating the proxies and systematic differences between proxy reconstructions and model simulations. As the difference between the estimates extends into the relatively recent period of the early nineteenth century it is possible to compare them with a reliable instrumental estimate of the temperature change over that period, provided that enough early thermometer observations, covering a wide enough expanse of the world, can be collected. One organisation which systematically made observations and collected the results was the English East India Company (EEIC), and their archives have been preserved in the British Library. Inspection of those archives revealed 900 log-books of EEIC ships containing daily instrumental measurements of temperature and pressure, and subjective estimates of wind speed and direction, from voyages across the Atlantic and Indian Oceans between 1789 and 1834. Those records have been extracted and digitised, providing 273 000 new weather records offering an unprecedentedly detailed view of the weather and climate of the late eighteenth and early nineteenth centuries. The new thermometer observations demonstrate that the large-scale temperature response to the Tambora eruption and the 1809 eruption was modest (perhaps 0.5 °C). This provides an out-of-sample validation for the proxy reconstructions - supporting their use for longer-term climate reconstructions. However, some of the climate model simulations in the CMIP5 ensemble show much larger volcanic effects than this - such simulations are unlikely to be accurate in this respect.

  12. Constraining the temperature history of the past millennium using early instrumental observations

    NASA Astrophysics Data System (ADS)

    Brohan, P.; Allan, R.; Freeman, E.; Wheeler, D.; Wilkinson, C.; Williamson, F.

    2012-05-01

    The current assessment that twentieth-century global temperature change is unusual in the context of the last thousand years relies on estimates of temperature changes from natural proxies (tree-rings, ice-cores etc.) and climate model simulations. Confidence in such estimates is limited by difficulties in calibrating the proxies and systematic differences between proxy reconstructions and model simulations. As the difference between the estimates extends into the relatively recent period of the early nineteenth century it is possible to compare them with a reliable instrumental estimate of the temperature change over that period, provided that enough early thermometer observations, covering a wide enough expanse of the world, can be collected. One organisation which systematically made observations and collected the results was the English East-India Company (EEIC), and their archives have been preserved in the British Library. Inspection of those archives revealed 900 log-books of EEIC ships containing daily instrumental measurements of temperature and pressure, and subjective estimates of wind speed and direction, from voyages across the Atlantic and Indian Oceans between 1789 and 1834. Those records have been extracted and digitised, providing 273 000 new weather records offering an unprecedentedly detailed view of the weather and climate of the late eighteenth and early nineteenth centuries. The new thermometer observations demonstrate that the large-scale temperature response to the Tambora eruption and the 1809 eruption was modest (perhaps 0.5 °C). This provides a powerful out-of-sample validation for the proxy reconstructions - supporting their use for longer-term climate reconstructions. However, some of the climate model simulations in the CMIP5 ensemble show much larger volcanic effects than this - such simulations are unlikely to be accurate in this respect.

  13. Radio continuum observations of early- and late-type spiral galaxies

    NASA Technical Reports Server (NTRS)

    Gioia, Isabella M.; Fabbiano, Giuseppina

    1987-01-01

    Two complete subsamples of early and late type spiral galaxies were mapped with the VLA in order to explore their radio and optical properties. The choice of the samples is explained, and the observational procedure and data reduction are described. The detection rate was 97 percent, with a detection limit of the order of 1-2 mJy. Total intensity data at 20 cm are presented for the whole sample, and 6 cm data for 11 galaxies. The results are presented in the form of tables and radio contour maps, and are discussed in comparison with previous work.

  14. Observation of x-ray resonant Raman scattering: The early days

    SciTech Connect

    Sparks, C.J.

    1995-12-31

    My early observation of Raman scattering came as a serendipitous by-product of our efforts to achieve the best possible signal for x-ray fluorescent analysis. We were also investigating the x-ray spectrum produced by a monochromatic x-ray beam striking metal targets which might contribute to the inelastic background. This background could contaminate the very weak diffusively distributed elastically scattered radiation associated with defects in the perfect periodicity of crystals. Energy analysis of the x-ray spectra created by monochromatic Cu K{sub {alpha}} and Mo K{sub {alpha}} radiation impinging on highly pure metal targets showed an inelastically scattered intensity related to the energy difference between the exciting radiation and the nearest bound state. Confirmation of these observations and availability of synchrotron radiation has led to wide application of this new x-ray spectroscopy in atomic physics including its use as a probe of the unoccupied density of states.

  15. Experimental observation of critical slowing down as an early warning of population collapse

    NASA Astrophysics Data System (ADS)

    Vorselen, Daan; Dai, Lei; Korolev, Kirill; Gore, Jeff

    2012-02-01

    Near tipping points marking population collapse or other critical transitions in complex systems small changes in conditions can result in drastic shifts in the system state. In theoretical models it is known that early warning signals can be used to predict the approach of these tipping points (bifurcations), but little is known about how these signals can be detected in practice. Here we use the budding yeast Saccharomyces cerevisiae to study these early warning signals in controlled experimental populations. We grow yeast in the sugar sucrose, where cooperative feeding dynamics causes a fold bifurcation; falling below a critical population size results in sudden collapse. We demonstrate the experimental observation of an increase in both the size and timescale of the fluctuations of population density near this fold bifurcation. Furthermore, we test the utility of theoretically predicted warning signals by observing them in two different slowly deteriorating environments. These findings suggest that these generic indicators of critical slowing down can be useful in predicting catastrophic changes in population biology.

  16. EARLY PHASE OBSERVATIONS OF EXTREMELY LUMINOUS TYPE Ia SUPERNOVA 2009dc

    SciTech Connect

    Yamanaka, M.; Arai, A.; Chiyonobu, S.; Fukazawa, Y.; Ikejiri, Y.; Itoh, R.; Komatsu, T.; Miyamoto, H.; Kawabata, K. S.; Kinugasa, K.; Hashimoto, O.; Honda, S.; Tanaka, M.; Imada, A.; Kuroda, D.; Maeda, K.; Nomoto, K.; Kamata, Y.; Kawai, N.; Konishi, K.

    2009-12-20

    We present early phase observations in optical and near-infrared wavelengths for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate of the light curve is DELTAm{sub 15}(B) = 0.65 +- 0.03, which is one of the slowest among SNe Ia. The peak V-band absolute magnitude is estimated to be M{sub V} = -19.90 +- 0.15 mag if no host extinction is assumed. It reaches M{sub V} = -20.19 +- 0.19 mag if we assume the host extinction of A{sub V} = 0.29 mag. SN 2009dc belongs to the most luminous class of SNe Ia, like SNe 2003fg and 2006gz. Our JHK{sub s} -band photometry shows that this SN is also one of the most luminous SNe Ia in near-infrared wavelengths. We estimate the ejected {sup 56}Ni mass of 1.2 +- 0.3 M{sub sun} for the no host extinction case (and of 1.6 +- 0.4 M{sub sun} for the host extinction of A{sub V} = 0.29 mag). The C II lambda6580 absorption line remains visible until a week after the maximum brightness, in contrast to its early disappearance in SN 2006gz. The line velocity of Si II lambda6355 is about 8000 km s{sup -1} around the maximum, being considerably slower than that of SN 2006gz. The velocity of the C II line is similar to or slightly less than that of the Si II line around the maximum. The presence of the carbon line suggests that the thick unburned C+O layer remains after the explosion. Spectropolarimetric observations by Tanaka et al. indicate that the explosion is nearly spherical. These observational facts suggest that SN 2009dc is a super-Chandrasekhar mass SN Ia.

  17. Fast Approximate Convex Decomposition 

    E-print Network

    Ghosh, Mukulika

    2012-10-19

    Approximate convex decomposition (ACD) is a technique that partitions an input object into "approximately convex" components. Decomposition into approximately convex pieces is both more efficient to compute than exact convex decomposition and can...

  18. Early Observations with the Rosetta/MIRO Instrument at comet 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Gulkis, Samuel

    2015-04-01

    The MIRO (Microwave Instrument on the Rosetta Orbiter) is a dual frequency (560 GHz and 190 GHz) heterodyne instrument consisting of two broadband channels (one in each frequency band) for continuum measurements, and a very high spectral resolution (44 kHz, 4096 channels) spectrometer interfaced with the submillimeter radiometer. Broad scientific objectives are to understand heat transport and ice sublimation in comets as interrelated processes reflecting properties acquired at time of formation and subsequent evolution and to understand important processes in the coma. The spectroscopic receiver is fixed tuned to measure simultaneously 8 molecular transitions of water, carbon monoxide, ammonia, and methanol. The continuum channels probe the nucleus sub-surface temperatures; the spectrometer channels are sensitive to gas abundance, velocity, and temperature. This paper will present an overview of the MIRO instrument, status of observations, and early results. Early results include detection and monitoring of water vapor in the coma, measurements of water gas production rates and their temporal and spatial variability, and measurements of subsurface temperatures and temperature gradients in the nucleus at depths of a few centimeters. The authors acknowledge funding support from NASA, CNES and CNRS/INSU, National Central University, and SNSB (Sweden). A part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We thank the operational support teams from the ESA Rosetta Mission.

  19. CONSTRAINTS ON TYPE Ia SUPERNOVA PROGENITOR COMPANIONS FROM EARLY ULTRAVIOLET OBSERVATIONS WITH SWIFT

    SciTech Connect

    Brown, Peter J.; Dawson, Kyle S.; Harris, David W.; Olmstead, Matthew; Milne, Peter; Roming, Peter W. A.

    2012-04-10

    We compare early ultraviolet (UV) observations of Type Ia supernovae (SNe Ia) with theoretical predictions for the brightness of the shock associated with the collision between SN ejecta and a companion star. Our simple method is independent of the intrinsic flux from the SN and treats the flux observed with the Swift/Ultra-Violet Optical Telescope as conservative upper limits on the shock brightness. Comparing this limit with the predicted flux for various shock models, we constrain the geometry of the SN progenitor-companion system. We find the model of a 1 M{sub Sun} red supergiant companion in Roche-lobe overflow to be excluded at a 95% confidence level for most individual SNe for all but the most unfavorable viewing angles. For the sample of 12 SNe taken together, the upper limits on the viewing angle are inconsistent with the expected distribution of viewing angles for red gaint stars as the majority of companions with high confidence. The separation distance constraints do allow main-sequence companions. A better understanding of the UV flux arising from the SN itself as well as continued UV observations of young SNe Ia will further constrain the possible progenitors of SNe Ia.

  20. Meteoric ion layers in the ionospheres of venus and mars: Early observations and consideration of the role of meteor showers

    E-print Network

    Withers, Paul

    have minimal observed effect on meteoric layers in Earth's ionosphere. In order to aid progress towardsMeteoric ion layers in the ionospheres of venus and mars: Early observations and consideration June 2013 Available online 26 June 2013 Abstract Layers of metal ions produced by meteoroid ablation

  1. Earth Observing System (EOS) Aqua Launch and Early Mission Attitude Support Experiences

    NASA Technical Reports Server (NTRS)

    Tracewell, D.; Glickman, J.; Hashmall, J.; Natanson, G.; Sedlak, J.

    2003-01-01

    The Earth Observing System (EOS) Aqua satellite was successfully launched on May 4,2002. Aqua is the second in the series of EOS satellites. EOS is part of NASA s Earth Science Enterprise Program, whose goals are to advance the scientific understanding of the Earth system. Aqua is a three-axis stabilized, Earth-pointing spacecraft in a nearly circular, sun-synchronous orbit at an altitude of 705 km. The Goddard Space Flight Center (GSFC) Flight Dynamics attitude team supported all phases of the launch and early mission. This paper presents the main results and lessons learned during this period, including: real-time attitude mode transition support, sensor calibration, onboard computer attitude validation, response to spacecraft emergencies, postlaunch attitude analyses, and anomaly resolution. In particular, Flight Dynamics support proved to be invaluable for successful Earth acquisition, fine-point mode transition, and recognition and correction of several anomalies, including support for the resolution of problems observed with the MODIS instrument.

  2. Shock Breakout and Early Light Curves of Type II-P Supernovae Observed with Kepler

    NASA Astrophysics Data System (ADS)

    Garnavich, Peter M.; Tucker, Bradley E.; Rest, Armin; Shaya, Edward J.; Olling, Robert; Kasen, Daniel; Villar, Victoria; KEGS

    2016-01-01

    We discovered two transient events in the Kepler field with light curves that strongly suggest they are type II-P supernovae. Using the fast cadence of the Kepler observations we precisely estimate the rise time to maximum for KSN2011a and KSN2011d as 10.5±0.4 and 13.3±0.4 rest-frame days respectively. We find the progenitor radius of KSN2011a (280±20 R?) to be significantly smaller than that for KSN2011d (490±20 R?) but both have similar explosion energies of 2.0±0.3 ×1051 erg.The rising light curve of KSN2011d is an excellent match to that predicted by simple models of exploding red supergiants (RSG). However, the early rise of KSN2011a is faster than the models predict possibly due to the supernova shockwave moving into pre-existing wind or mass-loss from the RSG. A mass loss rate of 10-4 M? yr-1 from the RSG can explain the fast rise without impacting the optical flux at maximum light or the shape of the post-maximum light curve.No shock breakout emission is seen in KSN2011a, but this is likely due to the circumstellar interaction suspected in the fast rising light curve. The early light curve of KSN2011d does show excess emission consistent with model predictions of a shock breakout. This is the first optical detection of a shock breakout from a type II-P supernova.

  3. Abundance patterns in the interstellar medium of early-type galaxies observed with Suzaku

    SciTech Connect

    Konami, Saori; Matsushita, Kyoko; Tamagawa, Toru; Nagino, Ryo

    2014-03-01

    We have analyzed 17 early-type galaxies, 13 ellipticals and 4 S0 galaxies, observed with Suzaku, and investigated metal abundances (O, Mg, Si, and Fe) and abundance ratios (O/Fe, Mg/Fe, and Si/Fe) in the interstellar medium (ISM). The emission from each on-source region, which is four times the effective radius, r {sub e}, is reproduced with one-temperature (1T) or two-temperature (2T) thermal plasma models as well as a multi-temperature model, using APEC plasma code version 2.0.1. The multi-temperature model gave almost the same abundances and abundance ratios with the 1T or 2T models. The weighted averages of the O, Mg, Si, and Fe abundances of all the sample galaxies derived from the multi-temperature model fits are 0.83 ± 0.04, 0.93 ± 0.03, 0.80 ± 0.02, and 0.80 ± 0.02 solar, respectively, in solar units according to the solar abundance table by Lodders in 2003. These abundances show no significant dependence on the morphology and environment. The systematic differences in the derived metal abundances between versions 2.0.1 and 1.3.1 of the APEC plasma codes were investigated. The derived O and Mg abundances in the ISM agree with the stellar metallicity within an aperture with a radius of one r {sub e} derived from optical spectroscopy. From these results, we discuss the past and present Type Ia supernova rates and star formation histories in early-type galaxies.

  4. Ultra-Fast Flash Observatory for the observation of early photons from gamma-ray bursts

    NASA Astrophysics Data System (ADS)

    Park, I. H.; Brandt, S.; Budtz-Jørgensen, C.; Castro-Tirado, A. J.; Chen, P.; Connell, P.; Eyles, C.; Grossan, B.; Huang, M.-H. A.; Jeong, S.; Jung, A.; Kim, J. E.; Kim, S.-W.; Lee, J.; Lim, H.; Linder, E. V.; Liu, T.-C.; Min, K. W.; Na, G. W.; Nam, J. W.; Panasyuk, M. I.; Reglero, V.; Ripa, J.; Rodrigo, J. M.; Smoot, G. F.; Svertilov, S.; Vedenkin, N.; Yashin, I.

    2013-02-01

    One of the least documented and understood aspects of gamma-ray bursts (GRBs) is the rise phase of the optical light curve. The Ultra-Fast Flash Observatory (UFFO) is an effort to address this question through extraordinary opportunities presented by a series of space missions including a small spacecraft observatory. The UFFO is equipped with a fast-response Slewing Mirror Telescope (SMT) that uses a rapidly moving mirror or mirror array to redirect the optical beam rather than slewing the entire spacecraft to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with sub-second response, for the first time, opening a completely new frontier in GRBs and transient studies. Its fast response measurements of the optical emission of dozens of GRBs each year will provide unique probes of the burst mechanism and test the prospect of GRBs as a new standard candle, potentially opening up the z > 10 universe. For the first time we employ a motorized slewing stage in SMT that can point to the event within 1 s after the x-ray trigger provided by the UFFO Burst Alert and Trigger Telescope. These two scientific instruments comprise the UFFO-pathfinder payload, which will be placed onboard the Lomonosov satellite and launched in 2013. The UFFO-pathfinder is the first step of our long-term program of space instruments for rapid-response GRB observations. We describe early photon science, our soon-to-be-launched UFFO-pathfinder hardware and mission, and our next planned mission, the UFFO-100.

  5. Early results on 67P/Churyumov-Gerasimenko observed by Rosetta/OSIRIS

    NASA Astrophysics Data System (ADS)

    Sierks, H.; Tubiana, C.; Snodgrass, C.; Agarwal, J.; Güttler, C.; Oklay, N.; Vincent, J.; Küppers, M.; Barbieri, C.; Lamy, P.; Rickman, H.; Rodrigo, R.; Koschny, D.; Hviid, S.; Mottola, S.; Osiris Team

    2014-07-01

    67P/Churyumov-Gerasimenko (67P) is the target comet of the ESA Rosetta mission. Launched in 2004, the Rosetta spacecraft woke up on the 20th of January 2014. After 36 months of deep space hibernation, Rosetta is now traveling to rendezvous with the comet at 4.1 au from the Sun, and it will follow 67P along its orbit, investigating how the comet changes and evolves while approaching the Sun. The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS (Keller et al., 2007) is the scientific imaging system onboard Rosetta. It comprises the Narrow Angle Camera (NAC) with wavelength range 250--1000 nm and the Wide Angle Camera (WAC) with wavelength range 240--720 nm. The NAC (FOV = 2.20×2.22 deg) is a system with high spatial resolution that allows an initial detection of the nucleus, studies its structure and rotation from relatively great distances, investigates the mineralogy of the surface, and studies the dust ejection processes. The WAC has much lower spatial resolution but, accordingly, a much wider field of view (about 11.35×12.11 deg). This allows observations of the 3-dimensional flow field of dust and gas near the nucleus and, in addition, provides a synoptic view of the whole nucleus. In summary, the WAC would provide long-term monitoring of the entire nucleus from close distances, while the NAC studies the details. The two camera units have been designed as a complementary pair, which, on one hand, addresses the study of the nucleus surface, and on the other hand, investigates the dynamics of the sublimation process. After commissioning in March 2014, OSIRIS took first images of comet 67P and its dust environment. Ground-based observations performed in 2007/08 when 67P was in the same orbital arc as it will be in March/April 2014, show that the comet was already active at 4.3 au inbound and that its behavior was repetitive during the last three apparitions (Snodgrass et al. 2013). We therefore expect to detect early comet activity by OSIRIS in March/April 2014. At this time, Rosetta will be at about 4 million kilometers from the comet and 67P will still be unresolved. We present results about the early cometary activity based on OSIRIS images. Orange-filter images (central wavelength 649.2 nm) will be used to determine the dust environment of 67P, since this wavelength range is quite free from gas emission lines. Moreover, a series of lightcurves will be taken to compare with the existing ones and look for possible changes in the rotational period due to its last perihelion passage.

  6. Assessment of skeletal changes after post-mortem exposure to fire as an indicator of decomposition stage.

    PubMed

    Keough, N; L'Abbé, E N; Steyn, M; Pretorius, S

    2015-01-01

    Forensic anthropologists are tasked with interpreting the sequence of events from death to the discovery of a body. Burned bone often evokes questions as to the timing of burning events. The purpose of this study was to assess the progression of thermal damage on bones with advancement in decomposition. Twenty-five pigs in various stages of decomposition (fresh, early, advanced, early and late skeletonisation) were exposed to fire for 30 min. The scored heat-related features on bone included colour change (unaltered, charred, calcined), brown and heat borders, heat lines, delineation, greasy bone, joint shielding, predictable and minimal cracking, delamination and heat-induced fractures. Colour changes were scored according to a ranked percentage scale (0-3) and the remaining traits as absent or present (0/1). Kappa statistics was used to evaluate intra- and inter-observer error. Transition analysis was used to formulate probability mass functions [P(X=j|i)] to predict decomposition stage from the scored features of thermal destruction. Nine traits displayed potential to predict decomposition stage from burned remains. An increase in calcined and charred bone occurred synchronously with advancement of decomposition with subsequent decrease in unaltered surfaces. Greasy bone appeared more often in the early/fresh stages (fleshed bone). Heat borders, heat lines, delineation, joint shielding, predictable and minimal cracking are associated with advanced decomposition, when bone remains wet but lacks extensive soft tissue protection. Brown burn/borders, delamination and other heat-induced fractures are associated with early and late skeletonisation, showing that organic composition of bone and percentage of flesh present affect the manner in which it burns. No statistically significant difference was noted among observers for the majority of the traits, indicating that they can be scored reliably. Based on the data analysis, the pattern of heat-induced changes may assist in estimating decomposition stage from unknown, burned remains. PMID:25460103

  7. Constraint on the early Universe by relic gravitational waves: From pulsar timing observations

    SciTech Connect

    Zhao Wen

    2011-05-15

    Recent pulsar timing observations by the Parkers Pulsar Timing Array (PPTA) and European Pulsar Timing Array (EPTA) teams obtained the constraint on the relic gravitational waves at the frequency f{sub *}=1/yr, which provides the opportunity to constrain H{sub *}, the Hubble parameter, when these waves crossed the horizon during inflation. In this paper, we investigate this constraint by considering the general scenario for the early Universe: we assume that the effective (average) equation-of-state w before the big bang nucleosynthesis stage is a free parameter. In the standard hot big-bang scenario with w=1/3, we find that the current PPTA result follows a bound H{sub *{<=}}1.15x10{sup -1}m{sub Pl}, and the EPTA result follows H{sub *{<=}}6.92x10{sup -2}m{sub Pl}. We also find that these bounds become much tighter in the nonstandard scenarios with w>1/3. When w=1, the bounds become H{sub *{<=}}5.89x10{sup -3}m{sub Pl} for the current PPTA and H{sub *{<=}}3.39x10{sup -3}m{sub Pl} for the current EPTA. In contrast, in the nonstandard scenario with w=0, the bound becomes H{sub *{<=}}7.76m{sub Pl} for the current PPTA.

  8. Abundance Patterns in the Interstellar Medium of Early-type Galaxies Observed with Suzaku

    E-print Network

    Konami, Saori; Nagino, Ryo; Tamagawa, Toru

    2014-01-01

    We have analyzed 17 early-type galaxies, 13 ellipticals and 4 S0's, observed with Suzaku, and investigated metal abundances (O, Mg, Si, and Fe) and abundance ratios (O/Fe, Mg/Fe, and Si/Fe) in the interstellar medium (ISM). The emission from each on-source region, which is 4 times effective radius, r_e, is reproduced with one- or two- temperature thermal plasma models as well as a multi-temperature model, using APEC plasma code v2.0.1. The multi-temperature model gave almost the same abundances and abundance ratios with the 1T or 2T models. The weighted averages of the O, Mg, Si, and Fe abundances of all the sample galaxies derived from the multi-temperature model fits are 0.83+-0.04, 0.93+-0.03, 0.80+-0.02, and 0.80+-0.02 solar, respectively, in solar units according to the solar abundance table by Lodders (2003). These abundances show no significant dependence on the morphology and environment. The systematic differences in the derived metal abundances between the version 2.0.1 and 1.3.1 of APEC plasma code...

  9. On the early onset of the NLC season 2013 as observed at ALOMAR

    NASA Astrophysics Data System (ADS)

    Fiedler, Jens; Baumgarten, Gerd; Berger, Uwe; Gabriel, Axel; Latteck, Ralph; Lübken, Franz-Josef

    2015-05-01

    On 21 May the ALOMAR RMR-lidar in Northern Norway detected the first noctilucent clouds (NLC) in 2013. This unusual early NLC onset was accompanied by ?6 K lower temperatures and higher water vapor mixing ratios at NLC altitudes from the end of April until the beginning of June. The zonal mean temperature and dynamic conditions in the Arctic middle atmosphere deviated in spring 2013 significantly from the mean conditions of the last 20 years. Furthermore the planetary wave activity in the high latitude stratosphere was enhanced from 20 April to beginning of May. The colder and wetter upper mesosphere in May 2013 is attributed to this unusual late planetary wave activity in the stratosphere, introducing a strong upwelling in the mesosphere, lower temperatures and an upward transport of water vapor, which finally resulted in earlier existence conditions for mesospheric ice particles. We regard this as a first evidence for intra-hemispheric coupling in the northern hemisphere extending from the stratosphere into the mesopause region. Yet it is unclear whether this is an unusual extreme event or an indicator for a change in the circulation due to the observed long-term cooling of the middle atmosphere.

  10. Characteristics of long recovery early VLF events observed by the North African AWESOME Network

    NASA Astrophysics Data System (ADS)

    Naitamor, S.; Cohen, M. B.; Cotts, B. R. T.; Ghalila, H.; Alabdoadaim, M. A.; Graf, K.

    2013-08-01

    Lightning strokes are capable of initiating disturbances in the lower ionosphere, whose recoveries persist for many minutes. These events are remotely sensed via monitoring subionospherically propagating very low frequency (VLF) transmitter signals, which are perturbed as they pass through the region above the lightning stroke. In this paper we describe the properties and characteristics of the early VLF signal perturbations, which exhibit long recovery times using subionospheric VLF transmitter data from three identical receivers located at Algiers (Algeria), Tunis (Tunisia), and Sebha (Libya). The results indicate that the observation of long recovery events depends strongly on the modal structure of the signal electromagnetic field and the distance from the disturbed region and the receiver or transmitter locations. Comparison of simultaneously collected data at the three sites indicates that the role of the causative lightning stroke properties (e.g., peak current and polarity), or that of transient luminous events may be much less important. The dominant parameter which determines the duration of the recovery time and amplitude appears to be the modal structure of the subionospheric VLF probe signal at the ionospheric disturbance, where scattering occurs, and the subsequent modal structure that propagates to the receiver location.

  11. Isothermal decomposition of ?-irradiated erbium acetate

    NASA Astrophysics Data System (ADS)

    Mahfouz, R. M.; Al-Shehri, S. M.; Monshi, M. A. S.; Alhaizan, A. I.; El-Salam, N. M. Abd

    Isothermal decomposition of un-irradiated and pre-?-irradiated erbium acetate has been investigated at different temperatures between 583 and 603 K. Irradiation was observed to enhance the rate of decomposition without modifying the mechanism of the thermal decomposition. Thermal decomposition of erbium acetate has been shown to proceed by a nucleation and growth mechanism (Erofe'ev model) both for un-irradiated and pre-?-irradiated samples. The enhancement of the decomposition was found to increase with an increase in the ?-ray dose applied to the sample and may be attributed to an increase in point defects and formation of additional nucleation centers generated in the host lattice. Thermodynamic values of the main decomposition process were calculated and evaluated.

  12. Isothermal decomposition of ?-irradiated samarium acetate

    NASA Astrophysics Data System (ADS)

    Mahfouz, R. M.; Monshi, M. A. S.; Alshehri, S. M.; Abd El-Salam, N. M.

    2000-10-01

    Isothermal decomposition of un-irradiated and pre-?-irradiated samarium acetate has been investigated at different temperatures between 613 and 633 K. Irradiation was observed to enhance the rate of decomposition without modifying the mechanism of thermal decomposition. Thermal decomposition of samarium acetate has been shown to proceed by two-dimensional phase-boundary reaction both for un-irradiated and pre-?-irradiated samples. The enhancement of the decomposition was found to increase with an increase in the ?-ray dose applied to the sample and may be attributed to an increase in point defects and formation of additional nucleation centers generated in the host lattice. Thermodynamic values of the main decomposition process were calculated and evaluated.

  13. Increasing Accountability Measures for Early Childhood Teachers Using Evaluation Models: Observation, Feedback, and Self-Assessment

    ERIC Educational Resources Information Center

    Reinking, Anna Krummel

    2015-01-01

    President Barack Obama and U.S. Secretary of Education Arne Duncan are promoting an early learning initiative focusing on the agenda of every four year old having equal access to high-quality early learning environments (Administration for Children and Families, 2013). One way the Federal government is supporting this proposal is through a grant;…

  14. Reading, Reasoning, and Literacy: Strategies for Early Childhood Education from the Analysis of Classroom Observations

    ERIC Educational Resources Information Center

    McKie, Brooke K.; Manswell Butty, Jo-Anne; Green, Rodney D.

    2012-01-01

    Researchers have posited that children generally learn to read in environments that are trusting, comfortable, and offer small group or one-to-one adult support, all of which are characteristics of a high quality early childhood education program. This evaluation research study examines the Pre-Kindergarten Incentive Program, an early childhood…

  15. Titan: Preliminary results on surface properties and photometry from VIMS observations of the early flybys

    USGS Publications Warehouse

    Buratti, B.J.; Sotin, C.; Brown, R.H.; Hicks, M.D.; Clark, R.N.; Mosher, J.A.; McCord, T.B.; Jaumann, R.; Baines, K.H.; Nicholson, P.D.; Momary, T.; Simonelli, D.P.; Sicardy, B.

    2006-01-01

    Cassini observations of the surface of Titan offer unprecedented views of its surface through atmospheric windows in the 1-5 ??m region. Images obtained in windows for which the haze opacity is low can be used to derive quantitative photometric parameters such as albedo and albedo distribution, and physical properties such as roughness and particle characteristics. Images from the early Titan flybys, particularly T0, Ta, and T5 have been analyzed to create albedo maps in the 2.01 and 2.73 ??m windows. We find the average normal reflectance at these two wavelengths to be 0.15??0.02 and 0.035??0.003, respectively. Titan's surface is bifurcated into two albedo regimes, particularly at 2.01 ??m. Analysis of these two regimes to understand the physical character of the surface was accomplished with a macroscopic roughness model. We find that the two types of surface have substantially different roughness, with the low-albedo surface exhibiting mean slope angles of ???18??, and the high-albedo terrain having a much more substantial roughness with a mean slope angle of ???34??. A single-scattering phase function approximated by a one-term Henyey-Greenstein equation was also fit to each unit. Titan's surface is back-scattering (g???0.3-0.4), and does not exhibit substantially different backscattering behavior between the two terrains. Our results suggest that two distinct geophysical domains exist on Titan: a bright region cut by deep drainage channels and a relatively smooth surface. The two terrains are covered by a film or a coating of particles perhaps precipitated from the satellite's haze layer and transported by eolian processes. Our results are preliminary: more accurate values for the surface albedo and physical parameters will be derived as more data is gathered by the Cassini spacecraft and as a more complete radiative transfer model is developed from both Cassini orbiter and Huygens Lander measurements. ?? 2006 Elsevier Ltd. All rights reserved.

  16. Nearby early-type galaxies with ionized gas: the UV emission from GALEX observations

    NASA Astrophysics Data System (ADS)

    Marino, A.; Rampazzo, R.; Bianchi, L.; Annibali, F.; Bressan, A.; Buson, L. M.; Clemens, M. S.; Panuzzo, P.; Zeilinger, W. W.

    2011-02-01

    We present GALEX far-ultraviolet (FUV, ?eff= 1538Å) and near-ultraviolet (NUV, ?eff= 2316Å) surface photometry of 40 early-type galaxies (ETGs) selected from a wider sample of 65 nearby ETGs showing emission lines in their optical spectra. We derive FUV and NUV surface brightness profiles, (FUV-NUV) colour profiles and D25 integrated magnitudes. We extend the photometric study to the optical r band from SDSS imaging for 14 of these ETGs. In general, the (FUV-NUV) radial colour profiles become redder with galactocentric distance in both rejuvenated (?4 Gyr) and old ETGs. Colour profiles of NGC 1533, NGC 2962, NGC 2974, NGC 3489 and IC 5063 show rings and/or arm-like structures, bluer than the body of the galaxy, suggesting the presence of recent star formation. Although seven of our ETGs show shell systems in their optical image, only NGC 7135 displays shells in the UV bands. We characterize the UV and optical surface brightness profiles, along the major axis, using a Sersic law. The Sersic law exponent, n, varies from 1 to 16 in the UV bands. S0 galaxies tend to have lower values of n (?5). The Sersic law exponent n= 4 seems to be a watershed: ETGs with n > 4 tend to have [?/Fe] greater than 0.15, implying a short star-formation time-scale. We find a significant correlation between the FUV-NUV colour and central velocity dispersions ?, with the UV colours getting bluer at larger ?. This trend is likely driven by a combined effect of ‘downsizing' and of the mass-metallicity relation. Based on GALEX observations: GI3-0087 PI R. Rampazzo.

  17. Simulated NASA Satellite Data Products for the NOAA Integrated Coral Reef Observation Network/Coral Reef Early Warning System

    NASA Technical Reports Server (NTRS)

    Estep, Leland; Spruce, Joseph P.

    2007-01-01

    This RPC (Rapid Prototyping Capability) experiment will demonstrate the use of VIIRS (Visible/Infrared Imager/Radiometer Suite) and LDCM (Landsat Data Continuity Mission) sensor data as significant input to the NOAA (National Oceanic and Atmospheric Administration) ICON/ CREWS (Integrated Coral Reef Observation System/Coral Reef Early Warning System). The project affects the Coastal Management Program Element of the Applied Sciences Program.

  18. Conflict Resolution and Children's Behaviour: Observing and Understanding Social and Cooperative Play in Early Years Educational Settings

    ERIC Educational Resources Information Center

    Broadhead, Pat

    2009-01-01

    This paper draws from continuing research into the growth of sociability and cooperation in young children. It began in the mid-1980s and has continued periodically in a range of early years educational settings across the 3-6 age range. The research has underpinned the development of an observational tool. This tool--the Social Play Continuum or…

  19. Highlights of early VIRTIS/ROSETTA observations: 67P/Churyumov-Gerasimenko seen from orbit

    NASA Astrophysics Data System (ADS)

    Erard, Stéphane; Capaccioni, Fabrizio; Filacchione, Gianricco; Arnold, Gabriele; Bockelee-Morvan, Dominique; Capria, Teresa; DeSanctis, Maria Cristina; Leyrat, Cédric; Tosi, Federico; Drossart, Pierre; Ciarniello, Mauro; Raponi, Andrea; Quirico, Eric; Schmitt, Bernard

    2015-08-01

    VIRTIS is the imaging spectrometer of the Rosetta mission, devoted to remote sensing studies of comet 67P/Churyumov-Gerasimenko (1). The instrument is made of a mapping channel covering the 0.3-5 ?m range at moderate spectral resolution (VIRTIS-M), and of a cross-dispersion spectrometer covering the 2-5um range with resolution ~3000 (VIRTIS-H). The most recent results will be presented at the meeting; early ones are discussed here.The nucleus is observed from a wide range of illumination conditions and spatial resolution (down to 2.5 m). Albedo, spectral parameters, and compositional maps have been derived for areas out of the polar night. The nucleus surface appears to be extremely homogeneous and dark. The inferred normal albedo is 0.060 ± 0.003 at 0.55 ?m (2), with distinct spectral slopes in the VIS and IR regions (5-25 and 1.5-5 % kÅ-1 respectively). The main spectral feature is a ubiquitous absorption in the 2.9-3.6 ?m range, consistent with non-volatile organic macromolecular materials (2,3). The most likely absorbents include carboxylic groups, alcoholic OH, and possibly NH4+ ions. However, the low albedo and marked slope suggest a mixture with opaque minerals (e.g. sulfides) or Fe-Ni alloys in the refractory crust. Ice is so far marginally detected in areas just emerging from shadow (4).The surface temperature is measured on the dayside as a function of local time and heliocentric distance. A maximum of 220K has been derived, with fast variations controlled by low thermal inertia. This is consistent with a surface covered by a porous crust, mainly devoid of water ice (5,6).Water vapor and carbon dioxide have been observed in the coma and their variability with altitude, geographic location and heliocentric distance has been studied. CO2/H2O ratio averages to 3-7%, but both species display different distributions. This suggests either different source regions, or seasonal variability (7).1- Coradini et al, SSR, 20072- Capaccioni et al., Science, 20153- Quirico et al, LPSC 20154- De Sanctis et al, LPSC 20155- Tosi et al, LPSC 20156- Leyrat et al, EGU 20157- Bockelée-Morvan et al, this meeting

  20. HUBBLE SPACE TELESCOPE WFC3 EARLY RELEASE SCIENCE: EMISSION-LINE GALAXIES FROM INFRARED GRISM OBSERVATIONS

    SciTech Connect

    Straughn, Amber N.; Gardner, Jonathan P.; Kuntschner, Harald; Kuemmel, Martin; Walsh, Jeremy R.; Cohen, Seth H.; Windhorst, Rogier A.; Malhotra, Sangeeta; Rhoads, James; O'Connell, Robert W.; Pirzkal, Norbert; Bond, Howard E.; Meurer, Gerhardt; McCarthy, Patrick J.; Hathi, Nimish P.; Balick, Bruce; Calzetti, Daniela; Disney, Michael J.; Dopita, Michael A.; Frogel, Jay A.

    2011-01-15

    We present grism spectra of emission-line galaxies (ELGs) from 0.6 to 1.6 {mu}m from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope. These new infrared grism data augment previous optical Advanced Camera for Surveys G800L 0.6-0.95 {mu}m grism data in GOODS-South from the PEARS program, extending the wavelength coverage well past the G800L red cutoff. The Early Release Science (ERS) grism field was observed at a depth of two orbits per grism, yielding spectra of hundreds of faint objects, a subset of which is presented here. ELGs are studied via the H{alpha}, [O III], and [O II] emission lines detected in the redshift ranges 0.2 {approx}< z {approx}< 1.4, 1.2 {approx}< z {approx}< 2.2, and 2.0 {approx}< z {approx}< 3.3, respectively, in the G102 (0.8-1.1 {mu}m; R {approx_equal} 210) and G141 (1.1-1.6 {mu}m; R {approx_equal} 130) grisms. The higher spectral resolution afforded by the WFC3 grisms also reveals emission lines not detectable with the G800L grism (e.g., [S II] and [S III] lines). From these relatively shallow observations, line luminosities, star formation rates, and grism spectroscopic redshifts are determined for a total of 48 ELGs to m A{sub B(F098M)} {approx_equal} 25 mag. Seventeen GOODS-South galaxies that previously only had photometric redshifts now have new grism-spectroscopic redshifts, in some cases with large corrections to the photometric redshifts ({Delta}z {approx_equal} 0.3-0.5). Additionally, one galaxy had no previously measured redshift but now has a secure grism-spectroscopic redshift, for a total of 18 new GOODS-South spectroscopic redshifts. The faintest source in our sample has a magnitude m{sub AB(F098M)}= 26.9 mag. The ERS grism data also reflect the expected trend of lower specific star formation rates for the highest mass galaxies in the sample as a function of redshift, consistent with downsizing and discovered previously from large surveys. These results demonstrate the remarkable efficiency and capability of the WFC3 NIR grisms for measuring galaxy properties to faint magnitudes and redshifts to z {approx}> 2.

  1. Parenting and the Family Check-Up: Changes in Observed Parent-Child Interaction Following Early Childhood Intervention.

    PubMed

    Sitnick, Stephanie L; Shaw, Daniel S; Gill, Anne; Dishion, Thomas; Winter, Charlotte; Waller, Rebecca; Gardner, Frances; Wilson, Melvin

    2015-01-01

    Coercion theory posits a cyclical relationship between harsh and coercive parent-child interactions and problem behavior beginning in early childhood. As coercive interactions have been theorized and found to facilitate the development and growth of early conduct problems, early interventions often target parenting to prevent or reduce early disruptive problem behavior. This study utilizes direct observations of parent-child interactions from the Early Steps Multisite study (N = 731; 369 boys) to examine the effect of the Family Check-Up, a family-centered intervention program, on measures of parent-child positive engagement and coercion from age 2 through 5, as well as on childhood problem behavior at age 5. Results indicate that high levels of parent-child positive engagement were associated with less parent-child coercion the following year, but dyadic coercion was unrelated to future levels of positive engagement. In addition, families assigned to the Family Check-Up showed increased levels of positive engagement at ages 3 and 5, and the association between positive engagement at age 3 and child problem behavior at age 5 was mediated by reductions in parent-child coercion at age 4. These findings provide longitudinal confirmation that increasing positive engagement in parent-child interaction can reduce the likelihood of coercive family dynamics in early childhood and growth in problem behavior. PMID:25133754

  2. Computing Cylindrical Algebraic Decomposition via Triangular Decomposition

    E-print Network

    Moreno Maza, Marc

    Computing Cylindrical Algebraic Decomposition via Triangular Decomposition Changbo Chen1 , Marc University, Beijing, China 3 East China Normal University, Shanghai, China Overview Cylindrical algebraic Cylindrical:we transform the initial partition and obtain an- other partition of C n into disjoint

  3. Early classification of multivariate temporal observations by extraction of interpretable shapelets

    PubMed Central

    2012-01-01

    Background Early classification of time series is beneficial for biomedical informatics problems such including, but not limited to, disease change detection. Early classification can be of tremendous help by identifying the onset of a disease before it has time to fully take hold. In addition, extracting patterns from the original time series helps domain experts to gain insights into the classification results. This problem has been studied recently using time series segments called shapelets. In this paper, we present a method, which we call Multivariate Shapelets Detection (MSD), that allows for early and patient-specific classification of multivariate time series. The method extracts time series patterns, called multivariate shapelets, from all dimensions of the time series that distinctly manifest the target class locally. The time series were classified by searching for the earliest closest patterns. Results The proposed early classification method for multivariate time series has been evaluated on eight gene expression datasets from viral infection and drug response studies in humans. In our experiments, the MSD method outperformed the baseline methods, achieving highly accurate classification by using as little as 40%-64% of the time series. The obtained results provide evidence that using conventional classification methods on short time series is not as accurate as using the proposed methods specialized for early classification. Conclusion For the early classification task, we proposed a method called Multivariate Shapelets Detection (MSD), which extracts patterns from all dimensions of the time series. We showed that the MSD method can classify the time series early by using as little as 40%-64% of the time series’ length. PMID:22873729

  4. Decompositional equivalence: A fundamental symmetry from which quantum theory follows

    E-print Network

    Chris Fields

    2015-04-20

    Decompositional equivalence is the principle that there is no preferred decomposition of the universe into subsystems. It is shown here, by using simple thought experiments, that quantum theory follows from decompositional equivalence together with Landauer's principle. This demonstration raises within physics a question previously left to psychology: how do human - or any - observers agree about what constitutes a "system of interest"?

  5. Parent and Parent Advisory Observation Measures as Indicators of Early Intervention Program Effects.

    ERIC Educational Resources Information Center

    And Others; Hanson, Marci J.

    1979-01-01

    Observations by parents of 11 Down's syndrome infants and observations by parent advisors on a criterion-referenced checklist were compared to observation by trained evaluators using the standardized Bayley Scales of Infant Development. (CL)

  6. SEMANTICBASED DECOMPOSITION OF

    E-print Network

    Ray, Indrakshi

    1 SEMANTIC­BASED DECOMPOSITION OF TRANSACTIONS Paul Ammann, Sushil Jajodia, Indrakshi Ray Center on providing algorithms necessary to implement a decomposition supplied by the database application developer and pays relatively little attention to what constitutes a desirable decomposition or how the developer

  7. Relational decomposition Lennart Beringer

    E-print Network

    Singh, Jaswinder Pal

    Relational decomposition Lennart Beringer Department of Computer Science, Princeton University, 35 decomposition, a technique for formally re- ducing termination-insensitive relational program logics to unary decomposition is applica- ble across heterogeneous pairs of transition systems. We apply our approach to justify

  8. Use of 13C NMR and ftir for elucidation of degradation pathways during natural litter decomposition and composting I. early stage leaf degradation

    USGS Publications Warehouse

    Wershaw, R.L.; Leenheer, J.A.; Kennedy, K.R.; Noyes, T.I.

    1996-01-01

    Oxidative degradation of plant tissue leads to the formation of natural dissolved organic carbon (DOC) and humus. Infrared (IR) and 13C nuclear magnetic resonance (NMR) spectrometry have been used to elucidate the chemical reactions of the early stages of degradation that give rise to DOC derived from litter and compost. The results of this study indicate that oxidation of the lignin components of plant tissue follows the sequence of O-demethylation, and hydroxylation followed by ring-fission, chain-shortening, and oxidative removal of substituents. Oxidative ring-fission leads to the formation of carboxylic acid groups on the cleaved ends of the rings and, in the process, transforms phenolic groups into aliphatic alcoholic groups. The carbohydrate components are broken down into aliphatic hydroxy acids and aliphatic alcohols.

  9. Small-scale early aggregation of green tide macroalgae observed on the Subei Bank, Yellow Sea.

    PubMed

    Hu, Song; Yang, Hong; Zhang, Jianheng; Chen, Changsheng; He, Peimin

    2014-04-15

    Massive green algae blooms became an environmental disaster in the Yellow Sea from 2008 to 2013. Recent studies suggested that recurrences of early aggregates of macroalgae were found over the Subei Bank, a unique shallow radial sand ridge system off the Jiangsu coast, China. Yearly field surveys have been carried out over this bank during the past five years (2009-2013), with an aim at identifying and qualifying the physical-biological mechanism for the early aggregation of algae. Data synthesis showed that early aggregation of macroalgae usually occurred from April-May as small-scale patches either over the intertidal mudflat of the Subei Bank or along local isobaths in the northern coastal area north of the bank. Both hydrographic and current measurements were performed by tracking a narrow patchy area of floating macroalgae (nearly 4 km in length and 5-10 m in width) on April 26, 2013, and the results showed that the algae aggregation was mainly caused by tide-induced convergence. This convergence was produced by the local geometrically controlled interaction of tidal currents with mudflats, which is believed to be a key physical mechanism for the early development of algal blooms in addition to marine ecosystem responses and human aquaculture activities. PMID:24569106

  10. Early-time VLA Observations and Broadband Afterglow Analysis of the Fermi/LAT Detected GRB 130907A

    NASA Astrophysics Data System (ADS)

    Veres, Péter; Corsi, Alessandra; Frail, Dale A.; Cenko, S. Bradley; Perley, Daniel A.

    2015-09-01

    We present multi-wavelength observations of the hyper-energetic gamma-ray burst (GRB) 130907A, a Swift-discovered burst with early radio observations starting at ?4 hr after the ?-ray trigger. GRB 130907A was also detected by the Fermi/LAT instrument and at late times showed a strong spectral evolution in X-rays. We focus on the early-time radio observations, especially at >10 GHz, to attempt to identify reverse shock signatures. While our radio follow-up of GRB 130907A ranks among the earliest observations of a GRB with the Karl G. Jansky Very Large Array, we did not see an unambiguous signature of a reverse shock. While a model with both reverse and forward shock can correctly describe the observations, the data is not constraining enough to decide upon the presence of the reverse-shock component. We model the broadband data using a simple forward-shock synchrotron scenario with a transition from a wind environment to a constant density interstellar medium (ISM) in order to account for the observed features. Within the confines of this model, we also derive the underlying physical parameters of the fireball, which are within typical ranges except for the wind density parameter (A*), which is higher than those for bursts with wind-ISM transition, but typical for the general population of bursts. We note the importance of early-time radio observations of the afterglow (and of well-sampled light curves) for unambiguously identifying the potential contribution of the reverse shock.

  11. Erbium hydride decomposition kinetics.

    SciTech Connect

    Ferrizz, Robert Matthew

    2006-11-01

    Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

  12. Proposed observations of gravity waves from the early Universe via "Millikan oil drops"

    E-print Network

    R. Y. Chiao

    2006-06-29

    Pairs of Planck-mass drops of superfluid helium coated by electrons (i.e., ``Millikan oil drops''), when levitated in a superconducting magnetic trap, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. This leads to the possibility of a Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves. Detection of the gravity-wave analog of the cosmic microwave background using these drops can discriminate between various theories of the early Universe.

  13. Unit III-3 -Singular value decomposition 1 Singular value decomposition

    E-print Network

    Birkett, Stephen

    Unit III-3 - Singular value decomposition 1 Unit III-3 Singular value decomposition Unit III-3 - Singular value decomposition 2 Eigenvalue decomposition re-visited · for a square matrix A the eigenvalue decomposition (EVD) can be written AU = DU ..... · ..... but only for some matrices as A = UDU-1 · what about

  14. An Observational Analysis of Behavior in Depressed Preschoolers: Further Validation of Early-Onset Depression

    ERIC Educational Resources Information Center

    Luby, Joan L.; Sullivan, Jill; Belden, Andy; Stalets, Melissa; Blankenship, Samantha; Spitznagel, Edward

    2006-01-01

    Objective: To investigate whether higher levels of negative and lower levels of positive behaviors could be observed in a sample of depressed preschoolers. Support for the validity of preschool depression is now available; however, objective evidence of negative behaviors among depressed preschoolers is needed. Method: A structured observational

  15. Systematic Observation of Early Adolescents in Educational Settings: The Good, the Bad, and the Ugly

    ERIC Educational Resources Information Center

    Gregory, Anne; Mikami, Amori Yee

    2015-01-01

    The growing use of systematic, empirically tested observational frameworks in school-based research is crucial for increasing the replicability and generalizability of findings across settings. That said, observations are often mistakenly assumed to be the "gold standard" assessment, without more nuanced discussions about the best uses…

  16. Early-infantile galactosialidosis: Clinical, biochemical, and molecular observations in a new patient

    SciTech Connect

    Zammarchi, E.; Donati, M.A.; Morrone, A.

    1996-08-23

    Few patients with the early-infantile form of galactosialidosis have been described to date. Presented here is the first Italian case. Fetal hydrops was detected by ultrasound at week 24 of gestation. At birth, the infant presented with hypotonial, massive edema, a flattened coarse facies. telangiectasias, and hepatosplenomegaly, but no dysostosis multiplex. The patient died 72 days postpartum. Excessive sialyloligosaccharides in urine, as well as vacuolation of lymphocytes and eosinophilic granulocytes in peripheral blood, were indicative of a lysosomal storage disease. In the patient`s fibroblasts, both {alpha}-neuraminidase and {beta}-galactosidase activities were severely reduced, and cathepsin A activity was <1% of control levels, confirming the biochemical diagnosis of galactosialidosis. However, in contrast to previously reported early-infantile cases, a normal amount of protective protein/cathepsin A mRNA was detected on Northern blots. This mutant transcript was translated into a precursor protein that was not processed into the mature enzyme and lacked both protective and catalytic activities. 28 refs., 4 figs., 1 tab.

  17. TEST FUSION IN ADULT FORAMINIFERA: A REVIEW WITH NEW OBSERVATIONS OF AN EARLY EOCENE NUMMULITES SPECIMEN

    PubMed Central

    Ferràndez-Cañadell, Carles; Briguglio, Antonino; Hohenegger, Johann; Wöger, Julia

    2015-01-01

    In foraminifera, so-called “double tests” usually arise due to abnormal growth originating mainly from twinning, but may also be caused by irregularities in the early chambers and by regeneration after test injury that modifies the direction of growth. A fourth cause of double tests has only rarely been reported: the fusion of the tests of two adult individuals. We studied an early Eocene Nummulites double test consisting of two adult individuals that fused after an extended period of independent growth. The specimen was studied using computed tomography with micrometric resolution (micro-CT) that allowed bi- and three-dimensional visualization of the internal structure. Before fusion each individual test had 30–36 chambers, which, by comparison with growth rates in recent nummulitids, implies at least three months of independent growth. After fusion, the compound test grew in two spirals that fused after about one whorl and then continued in a single spiral. To fuse their tests, either adult individuals have to be forced to do so or the allorecognition (ability to distinguish between self and another individual) mechanisms must fail. A possible explanation for the merged Nummulites tests in this study is forced fusion in attached individuals after surviving ingestion and digestion by a metazoan. Alternatively, environmental stress could lead to a failure of allorecognition mechanisms and/or foraminiferal motility. Once fused, subsequent growth seems to be determined mainly by the relative orientation of individual tests. In any case, the frequency in which adult fusion occurs remains unknown. PMID:26166916

  18. Decomposition Duality Reinhard Diestel

    E-print Network

    Diestel, Reinhard

    NOTE Decomposition Duality Reinhard Diestel The purpose of this note is just to point out a duality a decomposition angle. Let G, H be graphs. Consider a family D = (Gh)hH of induced subgraphs of G indexed by the vertices of H. Let us call D an H-decomposition of G (into the parts Gh) if (D1) every vertex of G lies

  19. Litter decomposition and nutrient dynamics in a phosphorus enriched everglades marsh

    E-print Network

    Florida, University of

    -1 Litter decomposition and nutrient dynamics in a phosphorus enriched everglades marsh WILLIAM F form 2 December 2004 Key words: Decomposition, Detritus, Everglades, Litter, Phosphorus, Wetland) of the Everglades in southern Florida, USA, to evaluate early stages of plant litter (detritus) decomposition along

  20. Countdown to 150 Observation, Natural History, and an Early Post-Darwinian

    E-print Network

    Agrawal, Anurag

    with milkweeds in The American Nat- uralist (James 1887), becoming one of the first in a long line of plant and ecology of many defense- offense interactions. In 1887, James used his observations on the milkweed milkweed (Asclepias syri

  1. Early Sixty-Day Observations of Nova Sagittarii 2015 No.2 Using a DSLR Camera

    NASA Astrophysics Data System (ADS)

    Deshmukh, S.

    2015-12-01

    Photometric observations of Nova Sagittarii 2015 No.2 were carried using a consumer grade DSLR camera. Observations have been made from the urban sky conditions for 60 days after the discovery. The brightness of the nova was monitored with reference to several nearby reference stars using Canon EOS 600D with CMOS sensor. Estimates were then transformed using a "median" B-V value of 0.28 into standard magnitude. Preliminary plot shows large variations, especially gradual rise and rapid falls.

  2. Development of Ego-Resiliency: Relations to Observed Parenting and Polymorphisms in the Serotonin Transporter Gene During Early Childhood

    PubMed Central

    Taylor, Zoe E.; Sulik, Michael J.; Eisenberg, Nancy; Spinrad, Tracy L.; Silva, Kassondra M.; Lemery-Chalfant, Kathryn; Stover, Daryn A.; Verrelli, Brian C.

    2013-01-01

    We used observed parenting behaviors, along with genetic variants and haplotypes of the serotonin transporter gene (SLC6A4), as predictors of children’s ego-resiliency during early childhood (N =153). Quality of mothers’ parenting was observed at 18 months of age and mothers’ reports of ego-resiliency were collected at six time points from 18 to 84 months. Genetic data were collected at 72 months. Observed parenting was positively associated with initial levels of children’s ego-resiliency. Furthermore, although individual genetic variants of the serotonin transporter gene (LPR, STin2) were not associated with ego-resiliency, the S10 haplotype (that combines information from these two variants) was negatively associated with initial levels of ego-resiliency. Both parenting and serotonin genetic variation uniquely predicted children’s ego-resiliency, suggesting an additive effect of genetic and parental factors. PMID:25346579

  3. EXCESS OPTICAL ENHANCEMENT OBSERVED WITH ARCONS FOR EARLY CRAB GIANT PULSES

    SciTech Connect

    Strader, M. J.; Mazin, B. A.; Spiro Jaeger, G. V.; Gwinn, C. R.; Meeker, S. R.; Szypryt, P.; Van Eyken, J. C.; Marsden, D.; Walter, A. B.; Ulbricht, G.; Johnson, M. D.; O'Brien, K.; Stoughton, C.; Bumble, B.

    2013-12-10

    We observe an extraordinary link in the Crab pulsar between the enhancement of an optical pulse and the timing of the corresponding giant radio pulse. At optical through infrared wavelengths, our observations use the high time resolution of ARray Camera for Optical to Near-IR Spectrophotometry, a unique superconducting energy-resolving photon-counting array at the Palomar 200 inch telescope. At radio wavelengths, we observe with the Robert C. Byrd Green Bank Telescope and the Green Bank Ultimate Pulsar Processing Instrument backend. We see an 11.3% ± 2.5% increase in peak optical flux for pulses that have an accompanying giant radio pulse arriving near the peak of the optical main pulse, in contrast to a 3.2% ± 0.5% increase when an accompanying giant radio pulse arrives soon after the optical peak. We also observe that the peak of the optical main pulse is 2.8% ± 0.8% enhanced when there is a giant radio pulse accompanying the optical interpulse. We observe no statistically significant spectral differences between optical pulses accompanied by and not accompanied by giant radio pulses. Our results extend previous observations of optical-radio correlation to the time and spectral domains. Our refined temporal correlation suggests that optical and radio emission are indeed causally linked, and the lack of spectral differences suggests that the same mechanism is responsible for all optical emission.

  4. Ultra-Fast Flash Observatory (uffo) for Observation of Early Photons from Gamma Ray Bursts

    NASA Astrophysics Data System (ADS)

    Park, I. H.; Ahmad, S.; Barrillon, P.; Brandt, S.; Budtz-Jorgensen, C.; Castro-Tirado, A. J.; Chen, P.; Choi, Y. J.; Connell, P.; Dagoret-Campagne, S.; Eyles, C.; Grossan, B.; Huang, M.-H. A.; Jung, A.; Jeong, S.; Kim, J. E.; Kim, M. B.; Kim, S.-W.; Kim, Y. W.; Krasnov, A. S.; Lee1, J.; Lim, H.; Linder, E. V.; Liu, T.-C.; Lund, N.; Min, K. W.; Na, G. W.; Nam, J. W.; Panasyuk, M. I.; Ripa, J.; Reglero, V.; Rodrigo, J. M.; Smoot, G. F.; Suh, J. E.; Svertilov, S.; Vedenkin, N.; Wang, M.-Z.; Yashin, I.

    2013-12-01

    One of the least documented and understood aspects of gamma-ray bursts (GRB) is the rise phase of the optical light curve. The Ultra-Fast Flash Observatory (UFFO) is an effort to address this question through extraordinary opportunities presented by a series of space missions including a small spacecraft observatory. The UFFO is equipped with a fast-response Slewing Mirror Telescope (SMT) which uses rapidly moving mirror or mirror arrays to redirect the optical beam rather than slewing the entire spacecraft to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with a sub-second response, for the first time, opening a completely new frontier in GRB and transient studies, the only GRB system which can point and measure on these time scales. Its fast response measurements of the optical emission of dozens of GRB each year will provide unique probes of the burst mechanism, shock breakouts in core-collapse supernovae, tidal disruptions around black holes, test Lorentz violation, be the electromagnetic counterpart to neutrino and gravitational wave signatures of the violent universe, and verify the prospect of GRB as a new standard candle potentially opening up the z>10 universe. As a first step, we employ a motorized slewing stage in SMT which can point to the event within 1s after X-ray trigger, in the UFFO-pathfinder payload onboard the Lomonosov satellite to be launched in 2012. The pathfinder was a small and limited, yet remarkably powerful micro-observatory for rapid optical response to bright gamma-ray bursts, the first part of our GRB and rapid-response long-term program. We describe the early photon science, the space mission of UFFO-pathfinder, and our plan for the next step.

  5. Autonomous Gaussian Decomposition

    NASA Astrophysics Data System (ADS)

    Lindner, Robert R.; Vera-Ciro, Carlos; Murray, Claire E.; Stanimirovi?, Snežana; Babler, Brian; Heiles, Carl; Hennebelle, Patrick; Goss, W. M.; Dickey, John

    2015-04-01

    We present a new algorithm, named Autonomous Gaussian Decomposition (AGD), for automatically decomposing spectra into Gaussian components. AGD uses derivative spectroscopy and machine learning to provide optimized guesses for the number of Gaussian components in the data, and also their locations, widths, and amplitudes. We test AGD and find that it produces results comparable to human-derived solutions on 21 cm absorption spectra from the 21 cm SPectral line Observations of Neutral Gas with the EVLA (21-SPONGE) survey. We use AGD with Monte Carlo methods to derive the H i line completeness as a function of peak optical depth and velocity width for the 21-SPONGE data, and also show that the results of AGD are stable against varying observational noise intensity. The autonomy and computational efficiency of the method over traditional manual Gaussian fits allow for truly unbiased comparisons between observations and simulations, and for the ability to scale up and interpret the very large data volumes from the upcoming Square Kilometer Array and pathfinder telescopes.

  6. Mid-Infrared Observational and Theoretical Studies of Star Formation and Early Solar Systems

    NASA Technical Reports Server (NTRS)

    Jones, Barbara

    1997-01-01

    The first 2 years of this program were used to make mid-IR observations of regions of star formation in the Orion nebula with the UCSD mid-IR camera at the UCSD/University of Minnesota telescope at Mt. Lemmon. These observations attempted to make the first systematic study of an extended region, known to have newly forming stars, and expected to have complex mid-IR emission. We discovered, to our surprise, that most of the thermal emission originated from extended sources rather than from point sources. This interesting observation made the analysis of the data much more complex, since the chop/nod procedures used at these wavelengths produce a differential measurement of the emission in one region compared to that in the adjacent region. Disentangling complex extended emission in such a situation is very difficult. In parallel with this work we were also observing comets in the thermal infrared, the other component of the original proposal. Some spectacular data on the comet Swift-Tuttle was acquired and published. A changing jet structure observed over a 2 week period is described. The rotation period of the comet can be measured at 66 hours. The size of the nucleus can also be estimated (at 30 km) from the observed excess flux from the nucleus. These data have lead to the development of models describing the action of dust particles of differing sizes and composition leaving the nucleus. The spatial distribution of the predicted IR emission has been compared to the observed jet structures, leading to estimates of both particles sizes, relative amounts of silicate vs organic grains, and the amounts of dust emitted in the jets vs isotopic emission.

  7. Mid-Infrared Observational and Theoretical Studies of Star Formation and Early Solar Systems

    NASA Astrophysics Data System (ADS)

    Jones, Barbara

    1997-06-01

    The first 2 years of this program were used to make mid-IR observations of regions of star formation in the Orion nebula with the UCSD mid-IR camera at the UCSD/University of Minnesota telescope at Mt. Lemmon. These observations attempted to make the first systematic study of an extended region, known to have newly forming stars, and expected to have complex mid-IR emission. We discovered, to our surprise, that most of the thermal emission originated from extended sources rather than from point sources. This interesting observation made the analysis of the data much more complex, since the chop/nod procedures used at these wavelengths produce a differential measurement of the emission in one region compared to that in the adjacent region. Disentangling complex extended emission in such a situation is very difficult. In parallel with this work we were also observing comets in the thermal infrared, the other component of the original proposal. Some spectacular data on the comet Swift-Tuttle was acquired and published. A changing jet structure observed over a 2 week period is described. The rotation period of the comet can be measured at 66 hours. The size of the nucleus can also be estimated (at 30 km) from the observed excess flux from the nucleus. These data have lead to the development of models describing the action of dust particles of differing sizes and composition leaving the nucleus. The spatial distribution of the predicted IR emission has been compared to the observed jet structures, leading to estimates of both particles sizes, relative amounts of silicate vs organic grains, and the amounts of dust emitted in the jets vs isotopic emission.

  8. A novel system for in-situ observations of early hydration reactions in wet conditions in conventional SEM

    SciTech Connect

    Katz, A.; Bentur, A. . E-mail: bentur@tx.technion.ac.il; Kovler, K.

    2007-01-15

    A novel system enabling wet microscopy in conventional SEM is described and its performance for in-situ study of hydration reactions is demonstrated. The technology is based on a sealed specimen capsule, which is protected from the microscope vacuum by an electron-transparent partition membrane. Thus, the wet sample can be placed and observed in a 'conventional' SEM without the need for drying or employing environmental SEM. Early hydration reactions of gypsum and cement systems were followed during the first 24 h.

  9. Observations of Nucleation and Early Stage Growth of Amorphous Silica on Carboxyl-Terminated Model Biosubstrates

    NASA Astrophysics Data System (ADS)

    Wallace, A. F.; Dove, P. M.

    2005-12-01

    Over Earth history, organisms have developed the ability to control the nucleation and growth of a broad range of nanocrystalline and amorphous materials. The formation of amorphous biosilica is of particular interest because silicifiers sequester gigatons of silica annually, and suppress dissolved silica levels in the ocean to current low levels. The ecological success of marine diatoms, which are arguably the most important silicifiers, places them alongside marine calcifiers as major players in the sequestration of organic carbon. Thus, the biologically mediated formation of amorphous silica plays a key role in the global cycling of silicon and carbon. During controlled biomineralization, nucleation typically occurs in designated locations. There is a substantial body of evidence suggesting that macromolecules in the cellular environment determine these locations by acting as templates to provide energetically favorable sites for the onset of mineral and amorphous material nucleation. In diatoms, silica formation is likely initiated through heterogeneous nucleation on functional portions of macromolecules inside the Silica Deposition Vesicle (SDV). Previous studies of silica nucleation have implicated multiple chemical moieties associated with the constituent amino acids and sugars of polysaccharides, proteins, and glycoproteins as probable sites for in vivo surface nucleation and patterning. These investigations have usually employed complex macromolecules that exhibit multiple functionalities, and un-characterized solution compositions, thus rendering a quantitative analysis of kinetic and thermodynamic processes impossible. The objective of this research is to experimentally test kinetic and thermodynamic controls exercised by surface moieties on silica nucleation. Our experimental model system uses synthetic organic substrates designed to mimic key features of the interfacial regions between the surrounding cellular environment and the amorphous silica surface. While controlling solution chemistry, we can make in situ measurements of nucleation and early stage growth at these interfaces with Atomic Force Microscopy (AFM). Preliminary experiments show that at pH 4 to 7, and supersaturations of 0.76 to 1.45 (? = ln([H4SiO4]/Ksp)), silica nucleates on carboxyl-terminated areas of the surface, that are less than 30 nm in diameter. The nuclei evolve during early stages of growth to spread over the surface into a sheet like form.

  10. Newly observed several peroxides from the gas phase ozonolysis of isoprene using a flow tube reactor and the water vapor effect on their formation and decomposition

    NASA Astrophysics Data System (ADS)

    Huang, D.; Chen, Z.; Zhao, Y.

    2012-12-01

    In recent years, one has been paying more and more attention to the formation of hydrogen peroxide and organic peroxides in the oxidation of volatile organic compounds (VOCs) because peroxides play important roles, such as reservoir of OH, HO2 and RO2 radicals, intermediate of Criegee radical chemistry and contributor to secondary organic aerosol. However, to the best of our knowledge, in the reaction of ozone with VOCs, only several small peroxides such as hydrogen peroxide (H2O2), hydroxymethyl hydroperoxide (HMHP), and methyl hydroperoxide (MHP) were separately identified, and their yields varied widely between different studies. Moreover, the information on the formation mechanism of peroxides in the ozonolysis of VOCs was mostly from a speculation rather than experimental evidence. Notably, a static chamber was employed in most of the previous studies, potentially resulting in the decomposition and heterogeneous reaction of peroxides on the chamber walls within an experiment time of tens of minutes to several hours, and possibly missing the details about the generation of peroxides. In the present study, we have used a flow quartz tube reactor to investigate the formation of peroxides in the ozonolysis of isoprene at various relative humidities (RH). A variety of peroxides have been detected on the tens of seconds of time scale using an online high performance liquid chromatography coupled with post-column derivatization using p-hydroxyphenylacetic acid and fluorescence detection. Our experimental results show that in addition to the three peroxides mentioned previously, more four ones, those are peroxyacetic acid (PAA) and three unknown peroxides, have been found. Furthermore, the total yield of the three small peroxides (H2O2, HMHP and MHP) is found to be similar to the result of literature; while for PAA and three unknown peroxides, they highlight a combined molar yield, for example, ~ 40% at 5% RH, much higher than that of the three small peroxides. Opposite to the previous conclusion that the peroxide yield would be positively correlated with RH, the yields of PAA and three unknown peroxides detected in the present study decreased with the RH increase. We tentatively assign these unknown peroxides to be hydroxyl hydroperoxides, which are produced by the reaction of different Criegee radicals with water. We used a box model coupled with the MCM v3.2 mechanism to simulate the reaction processes of the ozone-initiated oxidation of isoprene, adding the reaction between the gaseous water (and water dimer) and Criegee radicals and the decomposition of water-assisted hydroxyl hydroperoxides. We find that this modified mechanism would better explain the variation of peroxides with the RH increase, implying that molecular water and water cluster should be involved in the production and removal of peroxides in the future model.

  11. The Early Development of Object Knowledge: A Study of Infants' Visual Anticipations during Action Observation

    ERIC Educational Resources Information Center

    Hunnius, Sabine; Bekkering, Harold

    2010-01-01

    This study examined the developing object knowledge of infants through their visual anticipation of action targets during action observation. Infants (6, 8, 12, 14, and 16 months) and adults watched short movies of a person using 3 different everyday objects. Participants were presented with objects being brought either to a correct or to an…

  12. EARLY OBSERVATIONS AND ANALYSIS OF THE TYPE Ia SN 2014J IN M82

    E-print Network

    Marion, G. H.

    We present optical and near infrared (NIR) observations of the nearby Type Ia SN 2014J. Seventeen optical and 23 NIR spectra were obtained from 10 days before (–10d) to 10 days after (+10d) the time of maximum B-band ...

  13. Assessing the Observability of Hypernovae and Pair-Instability Supernovae in the Early Universe

    E-print Network

    Wiggins, Brandon K; Whalen, Daniel J; Even, Wesley P; Migenes, Victor; Fryer, Chris L

    2015-01-01

    The era of the universe's first (Population III) stars is essentially unconstrained by observation. Ultra-luminous and massive stars from this time altered the chemistry of the cosmos, provided the radiative scaffolding to support the formation of the first protogalaxies, and facilitated the creation and growth of now-supermassive black holes. Unfortunately, because these stars lie literally at the edge of the observable universe, they will remain beyond the reach of even the next generation of telescopes such as the James Webb Space Telescope and the Thirty-Meter Telescope. In this paper, we provide a primer to supernovae modeling and the first stars to make our discussion accessible to those new to or outside our field. We review recent work of the Los Alamos Supernova Light Curve Project and Brigham Young University to explore the possibility of probing this era through observations of the spectacular deaths of the first stars. We find that many such brilliant supernova explosions will be observable as far...

  14. Decomposition of Sodium Tetraphenylborate

    SciTech Connect

    Barnes, M.J.

    1998-11-20

    The chemical decomposition of aqueous alkaline solutions of sodium tetraphenylborate (NaTPB) has been investigated. The focus of the investigation is on the determination of additives and/or variables which influence NaTBP decomposition. This document describes work aimed at providing better understanding into the relationship of copper (II), solution temperature, and solution pH to NaTPB stability.

  15. In situ observations of nanoparticle early development kinetics at mineral-water interfaces.

    SciTech Connect

    Jun, Y. S.; Lee, B.; Waychunas, G. A.

    2010-10-08

    The early development of nanoparticles at mineral?water interfaces exerts crucial influences on the sequestration and transport of aqueous toxic species originating from both natural and anthropogenic sources. Homogeneous and heterogeneous nucleation often occur simultaneously, making it difficult to sort out whether toxic species are transported as free species, sorbed on nanoparticle surfaces, or trapped between aggregated nanoparticles. Here, using a newly developed X-ray scattering setup, we show how homogeneous nucleation and growth can be quantitatively separated from heterogeneous processes under aqueous conditions in real-time. Under conditions found in acid-mine-drainage (at pH 3.6 and [Fe{sup 3+}] = 10{sup -4} M), heterogeneous nucleation of iron oxide nanoparticles on quartz dominated homogeneous nucleation by a factor of 192 (by particle volume). The smallest heterogeneously formed nanoparticles had radii of 1.7 {+-} 0.5 nm, significantly smaller than the size estimated using classical nucleation theory (CNT). Based on the data, the dominant nucleation and growth mechanisms of iron oxide nanoparticles depending on ionic strength were presented. Our findings have implications for the formation and transport of nanoparticles, and thus toxins, in both environmental and biological systems.

  16. Observations of the Early Evening Boundary-Layer Transition Using a Small Unmanned Aerial System

    NASA Astrophysics Data System (ADS)

    Bonin, Timothy; Chilson, Phillip; Zielke, Brett; Fedorovich, Evgeni

    2013-01-01

    The evolution of the lower portion of the planetary boundary layer is investigated using the Small Multifunction Research and Teaching Sonde (SMARTSonde), an unmanned aerial vehicle developed at the University of Oklahoma. The study focuses on the lowest 200 m of the atmosphere, where the most noticeable thermodynamic changes occur during the day. Between October 2010 and February 2011, a series of flights was conducted during the evening hours on several days to examine the vertical structure of the lower boundary layer. Data from a nearby Oklahoma Mesonet tower was used to supplement the vertical profiles of temperature, humidity, and pressure, which were collected approximately every 30 min, starting 2 h before sunset and continuing until dusk. From the profiles, sensible and latent heat fluxes were estimated. These fluxes were used to diagnose the portion of the boundary layer that was most affected by the early evening transition. During the transition period, a shallow cool and moist layer near the ground was formed, and as the evening progressed the cooling affected an increasingly shallower layer just above the surface.

  17. High-resolution Observations of Molecular Gas in the Early-type Dwarf Galaxy NGC 404

    NASA Astrophysics Data System (ADS)

    Taylor, Christopher L.; Petitpas, Glen R.; del Rio, M. S.

    2015-06-01

    We present Berkeley-Illinois-Maryland Association CO (1-0) observations of the nearby dwarf elliptical galaxy NGC 404. The detected CO emission is concentrated in a small feature, slightly larger than the beam size, at the center of the optical galaxy. For an assumed CO-to-H2 conversion factor of 2.3 × {{10}20} (K km s-1)-1, the molecular gas mass is 9.0 × {{10}6} M?. The velocity field suggests rotation, with a position angle ˜90° different from previous single-dish observations. Both position angles are different from that of the extended H i distribution detected by del Rió et al. The lack of agreement between the postion angle of the CO velocity field and other position angles suggests an external origin for the central molecular gas clump in NGC 404.

  18. Earth Observations for Early Detection of Agricultural Drought in Countries at Risk: Contributions of the Famine Early Warning Systems Network (FEWS NET) (Invited)

    NASA Astrophysics Data System (ADS)

    Verdin, J. P.; Rowland, J.; Senay, G. B.; Funk, C. C.; Budde, M. E.; Husak, G. J.; Jayanthi, H.

    2013-12-01

    The Group on Earth Observations' Global Agricultural Monitoring (GEOGLAM) implementation plan emphasizes the information needs of countries at risk of food insecurity emergencies. Countries in this category are often vulnerable to disruption of agricultural production due to drought, while at the same time they lack well developed networks of in-situ observations to support early drought detection. Consequently, it is vital that Earth observations by satellites supplement those available from surface stations. The USGS, in its role as a FEWS NET implementing partner, has recently developed a number of new applications of satellite observations for this purpose. (1) In partnership with the University of California, Santa Barbara, a 30+ year time series of gridded precipitation estimates (CHIRPS) has been developed by blending NOAA GridSat B1 geostationary thermal infrared imagery with station observations using robust geostatistical methods. The core data set consists of pentadal (5-daily) accumulations from 1981-2013 at 0.05 degree spatial resolution between +/- 50 degrees latitude. Validation has been recently completed, and applications for gridded crop water balance calculations and mapping the Standardized Precipitation Index are in development. (2) Actual evapotranspiration (ETa) estimates using MODIS Land Surface Temperature (LST) data at 1-km have been successfully demonstrated using the operational Simplified Surface Energy Balance model with 8-day composites from the LPDAAC. A new, next-day latency implementation using daily LST swath data from the NASA LANCE server is in development for all the crop growing regions of the world. This ETa processing chain follows in the footsteps of (3) the expedited production of MODIS 250-meter NDVI images every five days at USGS EROS, likewise using LANCE daily swath data as input since 2010. Coverage includes Africa, Central Asia, the Middle East, Central America, and the Caribbean. (4) A surface water point monitoring method for pastoralist areas has been successfully demonstrated. It involves mapping small surface water bodies with ASTER and Landsat imagery, delineating their catchment areas with SRTM elevation data, and maintaining a continuous water balance calculation with satellite rainfall and weather model evaporation estimates to track relative fullness of these ephemeral water bodies. Piloted with NASA funds in partnership with Texas A&M University, the technique is now being implemented across the Sahel. (5) To move beyond monitoring and early warning to disaster risk management, loss exceedence probability functions are being derived for crop production shortfalls in FEWS NET countries. Drought hazard indicators, based on both ETa and crop water balance modeling forced by CHIRPS, have been used to develop regional crop drought risk models. In the case of ETa, the drought risk model provides the basis for index insurance in experiments being conducted in Senegal. A program of training events with GEO partners ensures that the data sets and applications are made available to scientists in FEWS NET countries.

  19. Early Fermi Gamma-ray Space Telescope Observations of the Quasar 3C454.3

    SciTech Connect

    Abdo, A

    2009-05-07

    This is the first report of Fermi Gamma-ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope (LAT), covering 2008 July 7-October 6, indicate strong, highly variable {gamma}-ray emission with an average flux of {approx} 3 x 10{sup -6} photons cm{sup -2} s{sup -1}, for energies > 100 MeV. The {gamma}-ray flux is variable, with strong, distinct, symmetrically-shaped flares for which the flux increases by a factor of several on a time scale of about three days. This variability indicates a compact emission region, and the requirement that the source is optically thin to pair-production implies relativistic beaming with Doppler factor {delta} > 8, consistent with the values inferred from VLBI observations of superluminal expansion ({delta} {approx} 25). The observed {gamma}-ray spectrum is not consistent with a simple power-law, but instead steepens strongly above {approx} 2 GeV, and is well described by a broken power-law with photon indices of {approx} 2.3 and {approx} 3.5 below and above the break, respectively. This is the first direct observation of a break in the spectrum of a high luminosity blazar above 100 MeV, and it is likely direct evidence for an intrinsic break in the energy distribution of the radiating particles. Alternatively, the spectral softening above 2GeV could be due to -ray absorption via photonphoton pair production on the soft X-ray photon field of the host AGN, but such an interpretation would require the dissipation region to be located very close ({approx}< 100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

  20. Recent increases in trifluoromethane (HFC-23) global emissions and early atmospheric changes observed for other hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Montzka, S. A.; Miller, B. R.; Battle, M. O.; Aydin, K. M.; Fahey, D. W.; Hall, B. D.; Miller, L.; Verhulst, K. R.; Saltzman, E.; McFarland, M.

    2009-12-01

    Trifluoromethane (HFC-23) is an unintended by-product of chlorodifluoromethane (HCFC-22) production and has a 100-yr global warming potential of 14,800. Firn-air and ambient air measurements of HFC-23 from three firn sampling excursions to Antarctica between 2001 and 2009 are used to construct a consistent atmospheric history for this chemical in the Southern Hemisphere. The results show continued increases in the atmospheric abundance of HFC-23 and imply substantial increases in HFC-23 global emissions since 2003. These emission increases are coincident with rapidly increasing HCFC-22 production in developing countries and are observed despite efforts in recent years to limit emissions of HFC-23 through the Kyoto Protocol’s Clean Development Mechanism. These results will be considered along with new observations of additional HFCs from archived air, firn air, and ongoing flask-air measurements. Considered together, atmospheric increases observed for hydrochlorofluorocarbons and hydrofluorocarbons accounted for ~9% of the increase in total direct radiative forcing from anthropogenic gases during 2003-2008, an addition that was slightly larger than attributable to N2O over this same period.

  1. Early stroke care in Italy—a steep way ahead: an observational study

    PubMed Central

    Citerio, G; Galli, D; Pesenti, A

    2006-01-01

    Objectives To measure the performance of selected Italian emergency medical system (EMS) dispatch centres managing calls for patients suffering from stroke. Data on outcome and on early treatment in the ED were collected. Methods Prospective data collection for a trimester from interventions for a suspected stroke in 13 EMS dispatch centres over five Italian regions. Results Altogether, 1041 calls for a suspected stroke were analysed. Mean intervals of the sequential phases were 2.3±2 minutes between call and ambulance dispatch, 8.4±5.5 minutes to reach the patient, 14.5±8.5 minutes on the scene, and 40.2±16.2 minutes between call and arrival at the ED. Interventions were performed in 56% of cases by a basic life support (BLS) crew, advanced life support (ALS) crews intervened in 28% of cases, and a combination of ALS and BLS in the remaining 16%. Mean diagnostic interval was 99±85 minutes between emergency system call and the first CT scan. This was performed 71±27 minutes after ED admission. Only 1.6% were admitted to a stroke unit. One month outcome according to GCS was good recovery in 32%, moderate disability in 28%, severe disability in 14%, and death in 25% of the patients. Conclusions Mean times show a rapid response of the selected EMS dispatch centres to calls for a suspected stroke. Nevertheless, mean times of the ED phase are still unacceptable according to international guidelines such as Brain Attack Coalition and American Stroke Association guidelines. Efforts should be spent to reduce the time between the arrival and the CT scan and more patients should be admitted to a stroke unit. PMID:16858091

  2. [CII] At 1 < z < 2: Observing Star Formation in the Early Universe with Zeus (1 and 2)

    NASA Technical Reports Server (NTRS)

    Ferkinhoff, Carl; Hailey-Dunsheath, S.; Nikola, T.; Oberst, T.; Parshley, S.; Stacey, G.; Benford, D.; staguhn, J.

    2010-01-01

    We report the detection of the [CII] 158 micron fine structure line from six submillimeter galaxies with redshifts between 1.12 and 1.73. This more than doubles the total number of [CII] 158 micron detections reported from high redshift sources. These observations were made with the Redshift(z) and Early Universe Spectrometer(ZEUS) at the Caltech Submillimeter Observatory on Mauna Kea, Hawaii between December 2006 and March 2009. ZEUS is a background limited submm echelle grating spectrometer (Hailey-Dunsheath 2009). Currently we are constructing ZEUS-2. This new instrument will utilize the same grating but will feature a two dimensional transition-edge sensed bolometer array with SQUID multiplexing readout system enabling simultaneous background limited observations in the 200, 340,450 and 650 micron telluric windows. ZEUS-2 will allow for long slit imaging spectroscopy in nearby galaxies and a [CII] survey from z 0.25 to 2.5.

  3. EARLY CHROMOSPHERIC RESPONSE DURING A SOLAR MICROFLARE OBSERVED WITH SOHO's CDS AND RHESSI

    SciTech Connect

    Brosius, Jeffrey W.; Holman, Gordon D. E-mail: Gordon.D.Holman@nasa.go

    2010-09-10

    We observed a solar microflare with RHESSI and SOHO's Coronal Diagnostic Spectrometer (CDS) on 2009 July 5. With CDS we obtained rapid cadence (7 s) stare spectra within a narrow field of view toward the center of AR 11024. The spectra contain emission lines from ions that cover a wide range of temperature, including He I (<0.025 MK), O V (0.25 MK), Si XII (2 MK), and Fe XIX (8 MK). The start of a precursor burst of He I and O V line emission preceded the steady increase of Fe XIX line emission by about 1 minute and the emergence of 3-12 keV X-ray emission by about 4 minutes. Thus, the onset of the microflare was observed in upper chromospheric (He I) and transition region (O V) line emission before it was detected in high-temperature flare plasma emission. Redshifted O V emission during the precursor suggests explosive chromospheric evaporation, but no corresponding blueshifts were found with either Fe XIX (which was very weak) or Si XII. Similarly, in subsequent microflare brightenings the O V and He I intensities increased (between 49 s and almost 2 minutes) before emissions from the hot flare plasma. Although these time differences likely indicate heating by a nonthermal particle beam, the RHESSI spectra provide no additional evidence for such a beam. In intervals lasting up to about 3 minutes during several bursts, the He I and O V emission line profiles showed secondary, highly blueshifted ({approx}-200 km s{sup -1}) components; during intervals lasting nearly 1 minute the velocities of the primary and secondary components were oppositely directed. Combined with no corresponding blueshifts in either Fe XIX or Si XII, this indicates that explosive chromospheric evaporation occurred predominantly at either comparatively cool temperatures (<2 MK) or within a hot temperature range to which our observations were not sensitive (e.g., between 2 and 8 MK).

  4. Early Chromospheric Response During a Solar Microflare Observed with SOHO's CDS and RHESSI

    NASA Technical Reports Server (NTRS)

    Brosius, Jeffrey W.; Holman, Gordon D.

    2010-01-01

    We observed a solar microflare with RHESSI and SOHO's Coronal Diagnostic Spectrometer (CDS) on 2009 July 5. With CDS we obtained rapid cadence (7 s) stare spectra within a narrow field of view toward the center of AR 11024. The spectra contain emission lines from ions that cover a wide range of temperature, including He I (< 0.025 MK), O V (0.25 MK), Si XII (2 MK), and Fe XIX (8 MK). The start of a precursor burst of He I and O V line emission preceded the steady increase of Fe XIX line emission by about 1 minute, and the emergence of 3-12 keV X-ray emission by about 4 minutes. Thus the onset of the microflare was observed in upper chromospheric (He I) and transition region (O V) line emission before it was detected in high temperature flare plasma emission. Redshifted O V emission during the precursor suggests explosive chromospheric evaporation, but no corresponding blueshifts were found with either Fe XIX (which was very weak) or Si XII. Similarly, in subsequent microflare brightenings the O V and He I intensities increased (between 49 s and almost 2 minutes) before emissions from the hot flare plasma. Although these time differences likely indicate heating by a nonthermal particle beam, the RHESSI spectra provide no additional evidence for such a beam. In intervals lasting up to about 3 minutes during several bursts, the He I and O V emission line profiles showed secondary, highly blueshifted ( approximately 200 km/s) components; during intervals lasting nearly 1 minute the velocities of the primary and secondary components were oppositely directed. Combined with no corresponding blueshifts in either Fe XIX or Si XII, this indicates that explosive chromospheric evaporation occurred predominantly at either comparatively cool temperatures (< 2 MK) or within a hot temperature range to which our observations were not sensitive (e.g., between 2 and 8 MK).

  5. The accelerations of the earth and moon from early astronomical observations

    NASA Technical Reports Server (NTRS)

    Muller, P. M.; Stephenson, F. R.

    1975-01-01

    An investigation has compiled a very large amount of data on central or near central solar eclipses as recorded in four principal ancient sources (Greek and Roman classics, medieval European chronicles, Chinese annals and astronomical treatises, and Late Babylonian astronomical texts) and applied careful data selectivity criteria and statistical methods to obtain reliable dates, magnitudes, and places of observation of the events, and thereby made estimates of the earth acceleration and lunar acceleration. The basic conclusion is that the lunar acceleration and both tidal and nontidal earth accelerations have been essentially constant during the period from 1375 B.C. to the present.

  6. The early Earth Observing System reference handbook: Earth Science and Applications Division missions, 1990-1997

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Prior to the launch of the Earth Observing System (EOS) series, NASA will launch and operate a wide variety of new earth science satellites and instruments, as well as undertake several efforts collecting and using the data from existing and planned satellites from other agencies and nations. These initiatives will augment the knowledge base gained from ongoing Earth Science and Applications Division (ESAD) programs. This volume describes three sets of ESAD activities -- ongoing exploitation of operational satellite data, research missions with upcoming launches between now and the first launch of EOS, and candidate earth probes.

  7. The Early History of Photometric Observations of Asteroids made at the Table Mountain Observatory

    NASA Astrophysics Data System (ADS)

    Young, James W.; Harris, Alan W.

    2009-05-01

    An Ascop S-20 photomultiplier tube mounted in a Mt. Wilson designed dry-ice cold-box assembly was used with a pulse-counting system to measure the colors, magnitudes, rotational rates, and phase coefficients of over 300 different asteroids between 1978 and 1993. During this time period, nearly one third of all known asteroid rotational rates (~150) were obtained from this effective system. All observations were made with manual telescopic pointing, with data written out long-hand utilizing the 0.6 meter telescope at JPL's Table Mountain Facility. Nearly 40 refereed journal (mostly ICARUS) papers were published containing these results, with yet a few more to come.

  8. Thermal Decomposition Mechanism of Butyraldehyde

    NASA Astrophysics Data System (ADS)

    Hatten, Courtney D.; Warner, Brian; Wright, Emily; Kaskey, Kevin; McCunn, Laura R.

    2013-06-01

    The thermal decomposition of butyraldehyde, CH_3CH_2CH_2C(O)H, has been studied in a resistively heated SiC tubular reactor. Products of pyrolysis were identified via matrix-isolation FTIR spectroscopy and photoionization mass spectrometry in separate experiments. Carbon monoxide, ethene, acetylene, water and ethylketene were among the products detected. To unravel the mechanism of decomposition, pyrolysis of a partially deuterated sample of butyraldehyde was studied. Also, the concentration of butyraldehyde in the carrier gas was varied in experiments to determine the presence of bimolecular reactions. The results of these experiments can be compared to the dissociation pathways observed in similar aldehydes and are relevant to the processing of biomass, foods, and tobacco.

  9. Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario

    USGS Publications Warehouse

    Walsh, Maureen G.; Lantry, Brian F.; Boscarino, Brent; Bowen, Kelly; Gerlofsma, Jocelyn; Schaner, Ted; Back, Richard; Questel, Jennifer; Smythe, A. Garry; Cap, Roberta; Goehle, Michael; Young, Bryan; Chalupnicki, Marc; Johnson, James H.; McKenna, James E.

    2010-01-01

    Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0. mm and an average caloric density of 611. cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.

  10. High-resolution observations of tungsten liner collapse and early jet formation

    SciTech Connect

    Winer, K.A.; Breithaupt, R.D.; Muelder, S.A.; Baum, D.W.

    1996-07-01

    High-resolution photography of collapsing tungsten-lined shaped charges has revealed surface texturing both similar to and strikingly different from that previously observed during copper liner collapse. The behavior of three types of tungsten-lined shaped charges, with different liner designs and high explosives but with similar tungsten processing, were characterized by image-converter camera and fast- framing camera photography, and flash x-ray radiography. 120-mm- diameter, trumpet-shaped Octol charges produced surface blistering near the base of the tungsten liner, probably due to inhomogeneities near the liner-explosive interface resulting from cast loading. 148- mm-diameter, quasi-conical LX-14 charges produced smooth shocked- surface texture similar to that observed in conical, copper-lined LX- 14 (Viper) charges. 81-mm-diameter, conical LX-20 charges produced severe radial texturing throughout the collapsing tungsten liner, which transitioned to azimuthal banding on the jet surface. For each type of charge, obscuring debris from the tungsten jet tip prevented clear imaging of the jet surface at late time. 8 refs., 6 figs., 2 tabs.

  11. A SOLAR CYCLE LOST IN 1793-1800: EARLY SUNSPOT OBSERVATIONS RESOLVE THE OLD MYSTERY

    SciTech Connect

    Usoskin, Ilya G.; Mursula, Kalevi; Arlt, Rainer; Kovaltsov, Gennady A.

    2009-08-01

    Because of the lack of reliable sunspot observations, the quality of the sunspot number series is poor in the late 18th century, leading to the abnormally long solar cycle (1784-1799) before the Dalton minimum. Using the newly recovered solar drawings by the 18-19th century observers Staudacher and Hamilton, we construct the solar butterfly diagram, i.e., the latitudinal distribution of sunspots in the 1790s. The sudden, systematic occurrence of sunspots at high solar latitudes in 1793-1796 unambiguously shows that a new cycle started in 1793, which was lost in the traditional Wolf sunspot series. This finally confirms the existence of the lost cycle that has been proposed earlier, thus resolving an old mystery. This Letter brings the attention of the scientific community to the need of revising the sunspot series in the 18th century. The presence of a new short, asymmetric cycle implies changes and constraints to sunspot cycle statistics, solar activity predictions, and solar dynamo theories, as well as for solar-terrestrial relations.

  12. Thermal decomposition of allylbenzene ozonide

    SciTech Connect

    Ewing, J.C.; Church, D.F.; Pryor, W.A. )

    1989-07-19

    Thermal decomposition of allylbenzene ozonide (ABO) at 98{degree}C in the liquid phase yields toluene, bibenzyl, phenylacetaldehyde, formic acid, and (benzyloxy)methyl formate as major products; benzyl chloride is formed when chlorinated solvents are employed. These products, as well as benzyl formate, are formed when ABO is decomposed at 37{degree}C. When the decomposition of ABO is carried out in the presence of 1-butanethiol, the product distribution changes: yields of toluene increase, no bibenzyl is formed, and decreases in yields of (benzyloxy)methyl formate, phenylacetladehyde, and benzyl chloride are observed. The decomposition of 1-octene ozonide (OTO) also was studied for comparison. The activation parameters for both ABO and OTO are similar (28.2 kcal/mol, log A = 13.6 and 26.6 kcal/mol, log A = 12.5, respectively); these data suggest that ozonides decompose by homolysis of the O-O bond, rather than by an alternative synchronous two-bond scission process. When ABO is decomposed at 37{degree}C in the presence of the spin traps 5,5-dimethyl-1-pyrroline N-oxide (DMPO) or 3,3,5,5-tetramethyl-1-pyrroline N-oxide (M{sub 4}PO), ESR signals are observed that are consistent with the trapping of benzyl and other carbon- and oxygen-centered radicals. A mechanism for the thermal decomposition of ABO that involves peroxide bond homolysis and subsequent {beta}-scission is proposed. Thus, Criegee ozonides decompose to give free radicals at quite modest temperatures.

  13. Decomposition of blackberry and broomsedge bluestem as influenced by ozone

    SciTech Connect

    Kim, J.S.; Chappelka, A.H.; Miller-Goodman, M.S.

    1998-07-01

    Many researchers have reported on individual plant responses to O{sub 3}, but few have investigated the effects of this pollutant on ecosystem function. This investigation examined the influence of O{sub 3} on short-term (Phase 1) litter decomposition of blackberry (Rubus cuneifolus Pursh.) and broomsedge bluestem (Andropogon virginicus L.), two plant species native to early successional forest communities in the southern US. Mixed blackberry/broomsedge litter (1:1) collected from plants exposed to different levels of O{sub 3} for one growing season was placed in open-top chambers and exposed to different O{sub 3} levels of treatments for 24 weeks. Litter also was incubated in microcosms in the laboratory t 25 or 30 C to determine the effects of climate change on O{sub 3}-treated litter. Initial C and N concentrations of the collected foliage did not differ significantly among treatments for either species. Blackberry litter had approximately twice as much N as broomsedge, and when collected from 2X O{sub 3} chambers, had significantly greater permanganate lignin than the other treatments. Initial permanganate lignin concentration of blackberry, over all O{sub 3} treatments, correlated significantly with remaining mass of the litter mixture after 24 wk exposure. Litter decomposed more slowly in the 2X chambers than in the other treatment chambers, regardless of litter source. Elevated O{sub 3}-exposed litter (2X) decomposed the slowest regardless of treatment applied. There were significant temperature and time effects observed with litter decomposition: litter incubated at 30 C decomposed faster than at 25 C. The data suggest O{sub 3} may influence substrate quality and microbial activity, thus reducing the rate of litter decomposition in early successional forest communities.

  14. Predicted and observed early effects of combined alpha and beta lung irradiation

    SciTech Connect

    Scott, B.R.; Hahn, F.F.; Snipes, M.B.; Newton, G.J.; Eidson, A.F.; Mauderly, J.L.; Boecker, B.B. )

    1990-12-01

    The nonstochastic radiobiological effects of combined alpha and beta irradiation of the lungs of rats from inhaled radionuclides were studied. Both respiratory functional morbidity at 18 mo and mortality from radiation pneumonitis within 18 mo after exposure were examined for rats exposed to the beta-emitter 147Pm, the alpha-emitter 238Pu, or both combined. The results were used to validate hazard-function models that were developed (1) for respiratory functional morbidity at 18 mo and (2) for lethality from radiation pneumonitis within 18 mo. Both models were found to adequately predict the experimental observations for chronic alpha plus beta irradiation of the lung. Based on this 18-mo study, a relative biological effectiveness of approximately seven was obtained for 238Pu alpha radiation compared to 147Pm beta radiation for both respiratory functional morbidity and lethality from radiation pneumonitis. However, the relative biological effectiveness for the alpha radiation is likely to increase with longer follow-up.

  15. Early Observations and Analysis of the Type Ia SN 2014J in M82

    NASA Astrophysics Data System (ADS)

    Marion, G. H.; Sand, D. J.; Hsiao, E. Y.; Banerjee, D. P. K.; Valenti, S.; Stritzinger, M. D.; Vinkó, J.; Joshi, V.; Venkataraman, V.; Ashok, N. M.; Amanullah, R.; Binzel, R. P.; Bochanski, J. J.; Bryngelson, G. L.; Burns, C. R.; Drozdov, D.; Fieber-Beyer, S. K.; Graham, M. L.; Howell, D. A.; Johansson, J.; Kirshner, R. P.; Milne, P. A.; Parrent, J.; Silverman, J. M.; Vervack, R. J., Jr.; Wheeler, J. C.

    2015-01-01

    We present optical and near infrared (NIR) observations of the nearby Type Ia SN 2014J. Seventeen optical and 23 NIR spectra were obtained from 10 days before (-10d) to 10 days after (+10d) the time of maximum B-band brightness. The relative strengths of absorption features and their patterns of development can be compared at one day intervals throughout most of this period. Carbon is not detected in the optical spectra, but we identify C I ?1.0693 in the NIR spectra. Mg II lines with high oscillator strengths have higher initial velocities than other Mg II lines. We show that the velocity differences can be explained by differences in optical depths due to oscillator strengths. The spectra of SN 2014J show that it is a normal SN Ia, but many parameters are near the boundaries between normal and high-velocity subclasses. The velocities for O I, Mg II, Si II, S II, Ca II, and Fe II suggest that SN 2014J has a layered structure with little or no mixing. That result is consistent with the delayed detonation explosion models. We also report photometric observations, obtained from -10d to +29d, in the UBVRIJH and Ks bands. The template fitting package SNooPy is used to interpret the light curves and to derive photometric parameters. Using RV = 1.46, which is consistent with previous studies, SNooPy finds that AV = 1.80 for E(B - V)host = 1.23 ± 0.06 mag. The maximum B-band brightness of -19.19 ± 0.10 mag was reached on February 1.74 UT ± 0.13 days and the supernova has a decline parameter, ?m 15, of 1.12 ± 0.02 mag.

  16. EARLY OBSERVATIONS AND ANALYSIS OF THE TYPE Ia SN 2014J IN M82

    SciTech Connect

    Marion, G. H.; Vinkó, J.; Sand, D. J.; Hsiao, E. Y.; Banerjee, D. P. K.; Joshi, V.; Venkataraman, V.; Ashok, N. M.; Valenti, S.; Howell, D. A.; Stritzinger, M. D.; Amanullah, R.; Johansson, J.; Binzel, R. P.; Bochanski, J. J.; Bryngelson, G. L.; Burns, C. R.; Drozdov, D.; Fieber-Beyer, S. K.; Graham, M. L.; and others

    2015-01-01

    We present optical and near infrared (NIR) observations of the nearby Type Ia SN 2014J. Seventeen optical and 23 NIR spectra were obtained from 10 days before (–10d) to 10 days after (+10d) the time of maximum B-band brightness. The relative strengths of absorption features and their patterns of development can be compared at one day intervals throughout most of this period. Carbon is not detected in the optical spectra, but we identify C I ?1.0693 in the NIR spectra. Mg II lines with high oscillator strengths have higher initial velocities than other Mg II lines. We show that the velocity differences can be explained by differences in optical depths due to oscillator strengths. The spectra of SN 2014J show that it is a normal SN Ia, but many parameters are near the boundaries between normal and high-velocity subclasses. The velocities for O I, Mg II, Si II, S II, Ca II, and Fe II suggest that SN 2014J has a layered structure with little or no mixing. That result is consistent with the delayed detonation explosion models. We also report photometric observations, obtained from –10d to +29d, in the UBVRIJH and K{sub s} bands. The template fitting package SNooPy is used to interpret the light curves and to derive photometric parameters. Using R{sub V} = 1.46, which is consistent with previous studies, SNooPy finds that A{sub V} = 1.80 for E(B – V){sub host} = 1.23 ± 0.06 mag. The maximum B-band brightness of –19.19 ± 0.10 mag was reached on February 1.74 UT ± 0.13 days and the supernova has a decline parameter, ?m {sub 15}, of 1.12 ± 0.02 mag.

  17. HST WFC3 Early Release Science: Emission-Line Galaxies from IR Grism Observations

    NASA Technical Reports Server (NTRS)

    Straughn, A. N.; Kuntschner, H.; Kuemmel, M.; Walsh, J. R.; Cohen, S. H.; Gardner, J. P.; Windhorst, R. A.; O'Connell, R. W.; Pirzkal, N.; Meurer, G.; McCarthy, P. J.; Hathi, N. P.; Malhotra, S.; Rhoads, J.; Balick, B.; Bond, H. E.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, J. A.; Hall, D. N. B.; Holtzman, J. A.; Kimlbe, R. A.; Trauger, J. T.; Young, E. T.

    2010-01-01

    We present grism spectra of emission line galaxies (ELGs) from 0.6-1.6 microns from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). These new infrared grism data augment previous optical Advanced Camera for Surveys G800L (0.6-0.95 micron) grism data in GOODS South, extending the wavelength coverage well past the G800L red cutoff. The ERS grism field was observed at a depth of 2 orbits per grism, yielding spectra of hundreds of faint objects, a subset of which are presented here. ELGs are studied via the Ha, [O III ], and [OII] emission lines detected in the redshift ranges 0.2 less than or equal to z less than or equal to 1.6, 1.2 less than or equal to z less than or equal to 2.4 and 2.0 less than or equal to z less than or equal to 3.6 respectively in the G102 (0.8-1.1 microns; R approximately 210) and C141 (1.1-1.6 microns; R approximately 130) grisms. The higher spectral resolution afforded by the WFC3 grisms also reveals emission lines not detectable with the G800L grism (e.g., [S II] and [S III] lines). From these relatively shallow observations, line luminosities, star formation rates, and grism spectroscopic redshifts are determined for a total of 25 ELGs to M(sub AB)(F098M) approximately 25 mag. The faintest source in our sample with a strong but unidentified emission line--is MAB(F098M)=26.9 mag. We also detect the expected trend of lower specific star formation rates for the highest mass galaxies in the sample, indicative of downsizing and discovered previously from large surveys. These results demonstrate the remarkable efficiency and capability of the WFC3 NIR grisms for measuring galaxy properties to faint magnitudes.

  18. Early Ultraviolet, Optical and X-Ray Observations of the Type IIP SN 2005cs in M51 with Swift

    E-print Network

    Peter J. Brown; Luc Dessart; Stephen T. Holland; Stefan Immler; Wayne Landsman; Stephane Blondin; Alexander J. Blustin; Alice Breeveld; Gulab C. Dewangan; Neil Gehrels; Robert B. Hutchins; Robert P. Kirshner; Keith O. Mason; Paolo A. Mazzali; Peter Milne; Maryam Modjaz; Peter W. A. Roming

    2006-12-19

    We report early photospheric-phase observations of the Type IIP Supernova (SN) 2005cs obtained by Swift's Ultraviolet-Optical and X-Ray Telescopes. Observations started within two days of discovery and continued regularly for three weeks. During this time the V-band magnitude remained essentially constant, while the UV was initially bright but steadily faded until below the brightness of an underlying UV-bright HII region. This UV decay is similar to SNe II observed by the International Ultraviolet Explorer. UV grism spectra show the P-Cygni absorption of MgII 2798A, indicating a photospheric origin of the UV flux. Based on non-LTE model atmosphere calculations with the CMFGEN code, we associate the rapid evolution of the UV flux with the cooling of the ejecta, the peak of the spectral energy distribution (SED) shifting from ~700A on June 30th to ~1200A on July 5th. Furthermore, the corresponding recombination of the ejecta, e.g., the transition from FeIII to FeII, induces considerable strengthening of metal line-blanketing at and above the photosphere, blocking more effectively this fading UV flux. SN2005cs was not detected in X-rays, and the upper limit to the X-ray luminosity yields a limit to the mass loss rate of the progenitor of about 10^-5 solar masses per year. Overall, Swift presents a unique opportunity to capture the early and fast evolution of Type II SNe in the UV, providing additional constraints on the reddening, the SED shortward of 4000A, and the ionization state and temperature of the photon-decoupling regions.

  19. Estimates for Lorentz factors of gamma-ray bursts from early optical afterglow observations

    SciTech Connect

    Hascoët, Romain; Beloborodov, Andrei M.; Daigne, Frédéric; Mochkovitch, Robert

    2014-02-10

    The peak time of optical afterglow may be used as a proxy to constrain the Lorentz factor ? of the gamma-ray burst (GRB) ejecta. We revisit this method by including bursts with optical observations that started when the afterglow flux was already decaying; these bursts can provide useful lower limits on ?. Combining all analyzed bursts in our sample, we find that the previously reported correlation between ? and the burst luminosity L {sub ?} does not hold. However, the data clearly show a lower bound ?{sub min} that increases with L {sub ?}. We suggest an explanation for this feature: explosions with large jet luminosities and ? < ?{sub min} suffer strong adiabatic cooling before their radiation is released at the photosphere; they produce weak bursts, barely detectable with present instruments. To test this explanation, we examine the effect of adiabatic cooling on the GRB location in the L {sub ?} – ? plane using a Monte Carlo simulation of the GRB population. Our results predict detectable on-axis 'orphan' afterglows. We also derive upper limits on the density of the ambient medium that decelerates the explosion ejecta. We find that the density in many cases is smaller than expected for stellar winds from normal Wolf-Rayet progenitors. The burst progenitors may be peculiar massive stars with weaker winds, or there might exist a mechanism that reduces the stellar wind a few years before the explosion.

  20. Predicted and observed early effects of combined alpha and beta lung irradiation.

    PubMed

    Scott, B R; Hahn, F F; Snipes, M B; Newton, G J; Eidson, A F; Mauderly, J L; Boecker, B B

    1990-12-01

    The nonstochastic radiobiological effects of combined alpha and beta irradiation of the lungs of rats from inhaled radionuclides were studied. Both respiratory functional morbidity at 18 mo and mortality from radiation pneumonitis within 18 mo after exposure were examined for rats exposed to the beta-emitter 147Pm, the alpha-emitter 238Pu, or both combined. The results were used to validate hazard-function models that were developed (1) for respiratory functional morbidity at 18 mo and (2) for lethality from radiation pneumonitis within 18 mo. Both models were found to adequately predict the experimental observations for chronic alpha plus beta irradiation of the lung. Based on this 18-mo study, a relative biological effectiveness of approximately seven was obtained for 238Pu alpha radiation compared to 147Pm beta radiation for both respiratory functional morbidity and lethality from radiation pneumonitis. However, the relative biological effectiveness for the alpha radiation is likely to increase with longer follow-up. PMID:2228607

  1. The effect of anhydrite on oil production in dolomite reservoirs - Some early observations

    SciTech Connect

    Buza, J.W.; Gould, J.F. )

    1992-04-01

    Results from wireline log analysis of recently drilled wells in the San Andres dolomite of the Slaughter and Levelland fields, west Texas, suggested a correlation between the presence of anhydrite and poor oil production. Log data from wells in the North-Central Levelland, Wright and Boyd Mallet units show that a high percentage of wells that perform poorly all have significant amounts of anhydrite in their reservoirs. Preliminary indications suggest that more than 20% anhydrite in the reservoir will severely reduce porosity and permeability and cause higher than average water saturations. In addition, the spacing of new wells indicates that reservoir degradation by anhydrite may be sporadic and areally restricted, allowing a poorly performing well to be located no more than 1500 ft from better performing wells that have low amounts of anhydrite. These observations imply that uneconomic infill well locations could be minimized by mapping the percent of anhydrite within the reservoir section. On a practical basis, the only way to acquire a sufficiently large enough database for good anhydrite prediction in west Texas is to refine log analysis to yield accurate mineralogy from cased hole logs.

  2. The performance of field scientists undertaking observations of early life fossils while in simulated space suit

    NASA Astrophysics Data System (ADS)

    Willson, D.; Rask, J. C.; George, S. C.; de Leon, P.; Bonaccorsi, R.; Blank, J.; Slocombe, J.; Silburn, K.; Steele, H.; Gargarno, M.; McKay, C. P.

    2014-01-01

    We conducted simulated Apollo Extravehicular Activity's (EVA) at the 3.45 Ga Australian 'Pilbara Dawn of life' (Western Australia) trail with field and non-field scientists using the University of North Dakota's NDX-1 pressurizable space suit to overview the effectiveness of scientist astronauts employing their field observation skills while looking for stromatolite fossil evidence. Off-world scientist astronauts will be faced with space suit limitations in vision, human sense perception, mobility, dexterity, the space suit fit, time limitations, and the psychological fear of death from accidents, causing physical fatigue reducing field science performance. Finding evidence of visible biosignatures for past life such as stromatolite fossils, on Mars, is a very significant discovery. Our preliminary overview trials showed that when in simulated EVAs, 25% stromatolite fossil evidence is missed with more incorrect identifications compared to ground truth surveys but providing quality characterization descriptions becomes less affected by simulated EVA limitations as the science importance of the features increases. Field scientists focused more on capturing high value characterization detail from the rock features whereas non-field scientists focused more on finding many features. We identified technologies and training to improve off-world field science performance. The data collected is also useful for NASA's "EVA performance and crew health" research program requirements but further work will be required to confirm the conclusions.

  3. Gauge- and frame-independent decomposition of nucleon spin

    SciTech Connect

    Wakamatsu, M.

    2011-01-01

    In a recent paper, we have shown that the way of gauge-invariant decomposition of the nucleon spin is not necessarily unique, but there still exists a preferable decomposition from the observational viewpoint. What was not complete in this argument is a fully satisfactory answer to the following questions. Does the proposed gauge-invariant decomposition, especially the decomposition of the gluon total angular momentum into its spin and orbital parts, correspond to observables which can be extracted from high-energy deep-inelastic-scattering measurements? Is this decomposition not only gauge invariant but also Lorentz frame independent, so that it is legitimately thought to reflect an intrinsic property of the nucleon? We show that we can answer both of these questions affirmatively by making full use of a gauge-invariant decomposition of the covariant angular-momentum tensor of QCD in an arbitrary Lorentz frame.

  4. Early evolution of a stratospheric volcanic eruption cloud as observed with TOMS and AVHRR

    NASA Astrophysics Data System (ADS)

    Schneider, David J.; Rose, William I.; Coke, Larry R.; Bluth, Gregg J. S.; Sprod, Ian E.; Krueger, Arlin J.

    1999-02-01

    This paper is a detailed study of remote sensing data from the total ozone mapping spectrometer (TOMS) and the advanced very high resolution radiometer (AVHRR) satellite detectors, of the 1982 eruption of El Chichón, Mexico. The volcanic cloud/atmosphere interactions in the first four days of this eruption were investigated by combining ultraviolet retrievals to estimate the mass of sulfur dioxide in the volcanic cloud [Krueger et al., 1995] with thermal infrared retrievals of the size, optical depth, and mass of fine-grained (1-10 ?m radius) volcanic ash [Wen and Rose, 1994]. Our study provides the first direct evidence of gravitational separation of ash from a stratospheric, gas-rich, plinian eruption column and documents the marked differences in residence times of volcanic ash and sulfur dioxide in volcanic clouds. The eruption column reached as high as 32 km [Carey and Sigurdsson, 1986] and was injected into an atmosphere with a strong wind shear, which allowed for an observation of the separation of sulfur dioxide and volcanic ash. The upper, more sulfur dioxide-rich part of the cloud was transported to the west in the stratosphere, while the fine-grained ash traveled to the south in the troposphere. The mass of sulfur dioxide released was estimated at 7.1 × 109 kg with the mass decreasing by approximately 4% 1 day after the peak. The mass of fine-grained volcanic ash detected was estimated at 6.5 × 109 kg, amounting to about 0.7% of the estimated mass of the ash which fell out in the mapped ash blanket close to the volcano. Over the following days, 98% of this remaining fine ash was removed from the volcanic cloud, and the effective radius of ash in the volcanic cloud decreased from about 8 ?m to about 4 ?m.

  5. Early evolution of a stratospheric volcanic eruption cloud as observed with TOMS and AVHRR

    USGS Publications Warehouse

    Schneider, D.J.; Rose, William I., Jr.; Coke, L.R.; Bluth, G.J.S.; Sprod, I.E.; Krueger, A.J.

    1999-01-01

    This paper is a detailed study of remote sensing data from the total ozone mapping spectrometer (TOMS) and the advanced very high resolution radiometer (AVHRR) satellite detectors, of the 1982 eruption of El Chicho??n, Mexico. The volcanic cloud/atmosphere interactions in the first four days of this eruption were investigated by combining ultraviolet retrievals to estimate the mass of sulfur dioxide in the volcanic cloud [Krueger et al., 1995] with thermal infrared retrievals of the size, optical depth, and mass of fine-grained (1-10 ??m radius) volcanic ash [Wen and Rose, 1994]. Our study provides the first direct evidence of gravitational separation of ash from a stratospheric, gas-rich, plinian eruption column and documents the marked differences in residence times of volcanic ash and sulfur dioxide in volcanic clouds. The eruption column reached as high as 32 km [Carey and Sigurdsson, 1986] and was injected into an atmosphere with a strong wind shear, which allowed for an observation of the separation of sulfur dioxide and volcanic ash. The upper, more sulfur dioxide-rich part of the cloud was transported to the west in the stratosphere, while the fine-grained ash traveled to the south in the troposphere. The mass of sulfur dioxide released was estimated at 7.1 ?? 109 kg with the mass decreasing by approximately 4% 1 day after the peak. The mass of fine-grained volcanic ash detected was estimated at 6.5 ?? 109 kg, amounting to about 0.7% of the estimated mass of the ash which fell out in the mapped ash blanket close to the volcano. Over the following days, 98% of this remaining fine ash was removed from the volcanic cloud, and the effective radius of ash in the volcanic cloud decreased from about 8 ??m to about 4 ??m. Copyright 1999 by the American Geophysical Union.

  6. Coupling experimental data and a prototype model to probe the physical and chemical processes of 2,4-dinitroimidazole solid-phase thermal decomposition

    SciTech Connect

    Behrens, R.; Minier, L.; Bulusu, S.

    1998-12-31

    The time-dependent, solid-phase thermal decomposition behavior of 2,4-dinitroimidazole (2,4-DNI) has been measured utilizing simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) methods. The decomposition products consist of gaseous and non-volatile polymeric products. The temporal behavior of the gas formation rates of the identified products indicate that the overall thermal decomposition process is complex. In isothermal experiments with 2,4-DNI in the solid phase, four distinguishing features are observed: (1) elevated rates of gas formation are observed during the early stages of the decomposition, which appear to be correlated to the presence of exogenous water in the sample; (2) this is followed by a period of relatively constant rates of gas formation; (3) next, the rates of gas formation accelerate, characteristic of an autocatalytic reaction; (4) finally, the 2,4-DNI is depleted and gaseous decomposition products continue to evolve at a decreasing rate. A physicochemical and mathematical model of the decomposition of 2,4-DNI has been developed and applied to the experimental results. The first generation of this model is described in this paper. Differences between the first generation of the model and the experimental data collected under different conditions suggest refinements for the next generation of the model.

  7. Real time observations of coastal algal blooms by an early warning system

    NASA Astrophysics Data System (ADS)

    Lee, J. H. W.; Hodgkiss, I. J.; Wong, K. T. M.; Lam, I. H. Y.

    2005-10-01

    In eutrophic sub-tropical coastal waters around Hong Kong, phytoplankton or unicellular microalgae can grow rapidly to very high concentrations under favourable environmental conditions. These harmful algal blooms (HABs) have led to massive fish kills, hypoxia, and beach closures. However, to date the causality and mechanism of coastal algal blooms are still poorly understood. A remotely controlled autonomous real time field monitoring system has been developed to continuously track the changes in chlorophyll fluorescence, dissolved oxygen and other hydro-meteorological variables at two representative mariculture zones. The system can give an alarm when a bloom is detected, so that timely manual water quality sampling can be carried out to supplement the telemetric data. During 2000-2003, the system has successfully tracked 19 algal blooms. In the shallow weakly flushed coastal water (depth 7-10 m, tidal current 5-19 cm s -1), the bloom is short-lived, typically lasting a few days to over a week, with chlorophyll and DO concentrations in the range of 20-40 mg m -3 and 2-15 g m -3, respectively. It is found that: (1) the chlorophyll concentration is strongly correlated with its past values in the previous week, suggesting an auto-regressive type of algal dynamics; (2) the dissolved oxygen can reach highly super-saturated levels (12 g m -3) during a diatom bloom, and decreases to below 4 g m -3 at the tail of the growth phase; (3) in contrast, a dinoflagellate bloom is characterized by a much more pronounced vertical structure. Diel vertical migration and aggregation to dense layers are clearly observed. Significant dissolved oxygen consumption is associated with the migration, resulting in DO drops by as much as 6 g m -3 during the bloom; (4) the predominance of diatoms and dinoflagellates at the two sites can be explained in terms of the different hydrographic and nutrient conditions (the N:P ratio). Net algal growth rate, sinking and swimming velocities are derived from the in situ bloom data. The 4-year high frequency data set provides a basis for development of models for forecast of harmful algal blooms.

  8. Observing slow EEG activity from same area as spikes in paediatric patients with focal epilepsy by using signal decomposition and dipole

    E-print Network

    Observing slow EEG activity from same area as spikes in paediatric patients with focal epilepsy.vanrumste@esat.kuleuven.ac.be Introduction The background EEG in patients with focal epilepsy often shows abnormalities related of the epileptogenic source. The algorithm has been applied to eight EEGs of paediatric patients with focal epilepsy

  9. Early polarization observations of the optical emission of gamma-ray bursts: GRB 150301B and GRB 150413A

    NASA Astrophysics Data System (ADS)

    Gorbovskoy, E. S.; Lipunov, V. M.; Buckley, D. A. H.; Kornilov, V. G.; Balanutsa, P. V.; Tyurina, N. V.; Kuznetsov, A. S.; Kuvshinov, D. A.; Gorbunov, I. A.; Vlasenko, D.; Popova, E.; Chazov, V. V.; Potter, S.; Kotze, M.; Kniazev, A. Y.; Gress, O. A.; Budnev, N. M.; Ivanov, K. I.; Yazev, S. A.; Tlatov, A. G.; Senik, V. A.; Dormidontov, D. V.; Parhomenko, A. V.; Krushinski, V. V.; Zalozhnich, I. S.; Castro-Tirado, R. Alberto; Sánchez-Ramírez, R.; Sergienko, Yu. P.; Gabovich, A.; Yurkov, V. V.; Levato, H.; Saffe, C.; Mallamaci, C.; Lopez, C.; Podest, F.; Vladimirov, V. V.

    2016-01-01

    We report early optical linear polarization observations of two gamma-ray bursts made with the MASTER robotic telescope network. We found the minimum polarization for GRB 150301B to be 8 per cent at the beginning of the initial stage, whereas we detected no polarization for GRB 150413A either at the rising branch or after the burst reached the power-law afterglow stage. This is the earliest measurement of the polarization (in cosmological rest frame) of gamma-ray bursts. The primary intent of the paper is to discover optical emission and publish extremely rare (unique) high-quality light curves of the prompt optical emission of gamma-ray bursts during the non-monotonic stage of their evolution. We report that our team has discovered the optical counterpart of one of the bursts, GRB 150413A.

  10. Purely dry mergers do not explain the observed evolution of massive early-type galaxies since z ? 1

    SciTech Connect

    Sonnenfeld, Alessandro; Treu, Tommaso; Nipoti, Carlo

    2014-05-10

    Several studies have suggested that the observed size evolution of massive early-type galaxies (ETGs) can be explained as a combination of dry mergers and progenitor bias, at least since z ? 1. In this paper we carry out a new test of the dry-merger scenario based on recent lensing measurements of the evolution of the mass density profile of ETGs. We construct a theoretical model for the joint evolution of the size and mass density profile slope ?' driven by dry mergers occurring at rates given by cosmological simulations. Such dry-merger model predicts a strong decrease of ?' with cosmic time, inconsistent with the almost constant ?' inferred from observations in the redshift range 0 < z < 1. We then show with a simple toy model that a modest amount of cold gas in the mergers—consistent with the upper limits on recent star formation in ETGs—is sufficient to reconcile the model with measurements of ?'. By fitting for the amount of gas accreted during mergers, we find that models with dissipation are consistent with observations of the evolution in both size and density slope, if ?4% of the total final stellar mass arises from the gas accreted since z ? 1. Purely dry merger models are ruled out at >99% CL. We thus suggest a scenario where the outer regions of massive ETGs grow by accretion of stars and dark matter, while small amounts of dissipation and nuclear star formation conspire to keep the mass density profile constant and approximately isothermal.

  11. Observation of early shell-dopant mix in OMEGA direct-drive implosions and comparisons with radiation-hydrodynamic simulations

    SciTech Connect

    Baumgaertel, J. A.; Bradley, P. A.; Hsu, S. C.; Cobble, J. A.; Hakel, P.; Tregillis, I. L.; Krasheninnikova, N. S.; Murphy, T. J.; Schmitt, M. J.; Shah, R. C.; Obrey, K. D.; Batha, S.; Johns, H.; Joshi, T.; Mayes, D.; Mancini, R. C.; Nagayama, T.

    2014-05-15

    Temporally, spatially, and spectrally resolved x-ray image data from direct-drive implosions on OMEGA were interpreted with the aid of radiation-hydrodynamic simulations. Neither clean calculations nor those using a turbulent mix model can explain fully the observed migration of shell-dopant material (titanium) into the core. Shell-dopant migration was observed via time-dependent, spatially integrated spectra, and spatially and spectrally resolved x-ray images of capsule implosions and resultant dopant emissions. The titanium emission was centrally peaked in narrowband x-ray images. In post-processed clean simulations, the peak titanium emission forms in a ring in self-emission images as the capsule implodes. Post-processed simulations with mix reproduce trends in time-dependent, spatially integrated spectra, as well having centrally peaked Ti emission in synthetic multiple monochromatic imager. However, mix simulations still do not transport Ti to the core as is observed in the experiment. This suggests that phenomena in addition to the turbulent mix must be responsible for the transport of Ti. Simple diffusion estimates are unable to explain the early Ti mix into the core. Mechanisms suggested for further study are capsule surface roughness, illumination non-uniformity, and shock entrainment.

  12. Climate forcing due to the 8200 cal yr BP event observed at Early Neolithic sites in the eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Weninger, Bernhard; Alram-Stern, Eva; Bauer, Eva; Clare, Lee; Danzeglocke, Uwe; Jöris, Olaf; Kubatzki, Claudia; Rollefson, Gary; Todorova, Henrieta; van Andel, Tjeerd

    2006-11-01

    We explore the hypothesis that the abrupt drainage of Laurentide lakes and associated rapid switch of the North Atlantic thermohaline circulation 8200 yr ago had a catastrophic influence on Neolithic civilisation in large parts of southeastern Europe, Anatolia, Cyprus, and the Near East. The event at 8200 cal yr BP is observed in a large number of high-resolution climate proxies in the Northern Hemisphere, and in many cases corresponds to markedly cold and arid conditions. We identify the relevant archaeological levels of major Neolithic settlements in Central Anatolia, Cyprus, Greece and Bulgaria, and examine published stratigraphic, architectural, cultural and geoarchaeological studies for these sites. The specific archaeological events and processes we observe at a number of these sites during the study interval 8400-8000 cal yr BP lead us to refine some previously established Neolithisation models. The introduction of farming to South-East Europe occurs in all study regions (Thrace, Macedonia, Thessaly, Bulgaria) near 8200 cal yr BP. We observe major disruptions of Neolithic cultures in the Levant, North Syria, South-East Anatolia, Central Anatolia and Cyprus, at the same time. We conclude that the 8200 cal yr BP aridity event triggered the spread of early farmers, by different routes, out of West Asia and the Near East into Greece and Bulgaria.

  13. The Helmholtz decomposition revisited

    NASA Astrophysics Data System (ADS)

    Petrascheck, D.

    2016-01-01

    In electrodynamics it is generally accepted that only vector fields decaying asymptotically more strongly than the inverse of the distance can be split into an irrotational and a solenoidal part, although this decomposition can clearly be applied to all vector fields that vanish asymptotically with a small power. Moreover this decomposition is valid even for vector fields that diverge weaker than linearly. A simple proof is presented.

  14. Battery Electric Vehicle Driving and Charging Behavior Observed Early in The EV Project

    SciTech Connect

    John Smart; Stephen Schey

    2012-04-01

    As concern about society's dependence on petroleum-based transportation fuels increases, many see plug-in electric vehicles (PEV) as enablers to diversifying transportation energy sources. These vehicles, which include plug-in hybrid electric vehicles (PHEV), range-extended electric vehicles (EREV), and battery electric vehicles (BEV), draw some or all of their power from electricity stored in batteries, which are charged by the electric grid. In order for PEVs to be accepted by the mass market, electric charging infrastructure must also be deployed. Charging infrastructure must be safe, convenient, and financially sustainable. Additionally, electric utilities must be able to manage PEV charging demand on the electric grid. In the Fall of 2009, a large scale PEV infrastructure demonstration was launched to deploy an unprecedented number of PEVs and charging infrastructure. This demonstration, called The EV Project, is led by Electric Transportation Engineering Corporation (eTec) and funded by the U.S. Department of Energy. eTec is partnering with Nissan North America to deploy up to 4,700 Nissan Leaf BEVs and 11,210 charging units in five market areas in Arizona, California, Oregon, Tennessee, and Washington. With the assistance of the Idaho National Laboratory, eTec will collect and analyze data to characterize vehicle consumer driving and charging behavior, evaluate the effectiveness of charging infrastructure, and understand the impact of PEV charging on the electric grid. Trials of various revenue systems for commercial and public charging infrastructure will also be conducted. The ultimate goal of The EV Project is to capture lessons learned to enable the mass deployment of PEVs. This paper is the first in a series of papers documenting the progress and findings of The EV Project. This paper describes key research objectives of The EV Project and establishes the project background, including lessons learned from previous infrastructure deployment and PEV demonstrations. One such previous study was a PHEV demonstration conducted by the U.S. Department of Energy's Advanced Vehicle Testing Activity (AVTA), led by the Idaho National Laboratory (INL). AVTA's PHEV demonstration involved over 250 vehicles in the United States, Canada, and Finland. This paper summarizes driving and charging behavior observed in that demonstration, including the distribution of distance driven between charging events, charging frequency, and resulting proportion of operation charge depleting mode. Charging demand relative to time of day and day of the week will also be shown. Conclusions from the PHEV demonstration will be given which highlight the need for expanded analysis in The EV Project. For example, the AVTA PHEV demonstration showed that in the absence of controlled charging by the vehicle owner or electric utility, the majority of vehicles were charged in the evening hours, coincident with typical utility peak demand. Given this baseline, The EV Project will demonstrate the effects of consumer charge control and grid-side charge management on electricity demand. This paper will outline further analyses which will be performed by eTec and INL to documenting driving and charging behavior of vehicles operated in a infrastructure-rich environment.

  15. Observations of middle atmosphere CO from the UARS ISAMS during the early northern winter 1991/92

    SciTech Connect

    Allen, D.R.; Stanford, J.L.; Lopez-Valverde, M.A.; Nakamura, N.; Lary, D.J.; Douglass, A.R.; Cerniglia, M.C.; Remedios, J.J.; Taylor, F.W.

    1999-02-15

    Structure and kinematics of carbon monoxide in the upper stratosphere and lower mesosphere are studied for the early northern winter 1991/92 using the Upper Atmosphere Research Satellite Improved Stratospheric and Mesospheric Sounder (ISAMS) measurements. The study is aided by data from a 6-week parameterized-chemistry run of the Goddard Space Flight Center 3D Chemistry and Transport Model (CTM), initialized on 8 December 1991. Generally, CO mixing ratios increase with height due to the increasing source contribution from CO{sub 2} photolysis. In the tropical upper stratosphere, however, a local maximum in CO mixing ratio occurs. A simple photochemical model is used to show that this feature results largely from methane oxidation. In the extratropics the photochemical lifetime of CO is long, and therefore its evolution is dictated by large-scale motion of air, evidenced by strong correlation with Ertel potential vorticity. This makes CO one of the few useful observable tracers at the stratopause level and above. Thus, CO maps are used to study the synoptic evolution of the polar vortex in early January 1992. Modified Lagrangian mean mixing diagnostics are applied to ISAMS and CTM data to examine the strength of the mixing barrier at the polar vortex edge. It is demonstrated that planetary wave activity weakens the barrier, promoting vortex erosion. The vortex erosion first appears in the lower mesosphere and subsequently descends through the upper stratosphere, and is attributed to effects of planetary wave dissipation. Agreement between ISAMS and CTM is good in the horizontal distribution of CO through the examined period, but vertical CO gradients in the CTM weaken with time relative to the ISAMS observations.

  16. On the Helmert-blocking technique: its acceleration by block Choleski decomposition and formulae to insert observations into an adjusted network

    PubMed Central

    Del Rio, Eduardo; Oliveira, Leonardo

    2015-01-01

    The Helmert-blocking technique is a common approach to adjust large geodetic networks like Europeans and Brazilians. The technique is based upon a division of the network into partial networks called blocks. This way, the global network adjustment can be done by manipulating these blocks. Here we show alternatives to solve the block system that arises from the application of the technique. We show an alternative that optimizes its implementation as the elapsed processing time is decreased by about 33%. We also show that to insert observations into an adjusted network it is not necessary to readjust the whole network. We show the formulae to insert new observations into an adjusted network that are more efficient than simply readjusting the whole new network. PMID:26064634

  17. On the Helmert-blocking technique: its acceleration by block Choleski decomposition and formulae to insert observations into an adjusted network.

    PubMed

    Del Rio, Eduardo; Oliveira, Leonardo

    2015-04-01

    The Helmert-blocking technique is a common approach to adjust large geodetic networks like Europeans and Brazilians. The technique is based upon a division of the network into partial networks called blocks. This way, the global network adjustment can be done by manipulating these blocks. Here we show alternatives to solve the block system that arises from the application of the technique. We show an alternative that optimizes its implementation as the elapsed processing time is decreased by about 33%. We also show that to insert observations into an adjusted network it is not necessary to readjust the whole network. We show the formulae to insert new observations into an adjusted network that are more efficient than simply readjusting the whole new network. PMID:26064634

  18. Observation of Ds1(2536)+?D+?-K+ and angular decomposition of Ds1(2536)+?D*+KS0

    NASA Astrophysics Data System (ADS)

    Balagura, V.; Adachi, I.; Aihara, H.; Arinstein, K.; Aulchenko, V.; Aushev, T.; Bakich, A. M.; Barberio, E.; Bay, A.; Belous, K.; Bhardwaj, V.; Bitenc, U.; Bondar, A.; Bozek, A.; Bra?ko, M.; Brodzicka, J.; Browder, T. E.; Chang, M.-C.; Chao, Y.; Chen, A.; Chen, W. T.; Cheon, B. G.; Chistov, R.; Cho, I.-S.; Choi, Y.; Dalseno, J.; Danilov, M.; Drutskoy, A.; Eidelman, S.; Epifanov, D.; Gabyshev, N.; Garmash, A.; Golob, B.; Ha, H.; Haba, J.; Hara, T.; Hastings, N. C.; Hayasaka, K.; Hayashii, H.; Hazumi, M.; Heffernan, D.; Hoshi, Y.; Hou, W.-S.; Hyun, H. J.; Inami, K.; Ishikawa, A.; Ishino, H.; Itoh, R.; Iwasaki, M.; Iwasaki, Y.; Kah, D. H.; Kaji, H.; Katayama, N.; Kawai, H.; Kawasaki, T.; Kichimi, H.; Kim, H. J.; Kim, H. O.; Kim, Y. J.; Kinoshita, K.; Korpar, S.; Križan, P.; Krokovny, P.; Kuo, C. C.; Kuzmin, A.; Kwon, Y.-J.; Lange, J. S.; Lee, M. J.; Lee, S. E.; Lesiak, T.; Limosani, A.; Lin, S.-W.; Liu, Y.; Liventsev, D.; Mandl, F.; McOnie, S.; Medvedeva, T.; Mitaroff, W.; Miyake, H.; Miyata, H.; Miyazaki, Y.; Mizuk, R.; Mohapatra, D.; Moloney, G. R.; Nagasaka, Y.; Nakano, E.; Nakao, M.; Nakazawa, H.; Natkaniec, Z.; Nishida, S.; Nitoh, O.; Ogawa, S.; Ohshima, T.; Okuno, S.; Olsen, S. L.; Ostrowicz, W.; Ozaki, H.; Pakhlov, P.; Pakhlova, G.; Palka, H.; Park, C. W.; Peak, L. S.; Pestotnik, R.; Piilonen, L. E.; Sakai, Y.; Schneider, O.; Senyo, K.; Shapkin, M.; Shen, C. P.; Shibuya, H.; Shiu, J.-G.; Somov, A.; Stani?, S.; Stari?, M.; Sumiyoshi, T.; Tamai, K.; Tanaka, M.; Taylor, G. N.; Teramoto, Y.; Tikhomirov, I.; Uehara, S.; Ueno, K.; Uglov, T.; Unno, Y.; Uno, S.; Urquijo, P.; Usov, Y.; Varner, G.; Vervink, K.; Villa, S.; Vinokurova, A.; Wang, C. C.; Wang, C. H.; Wang, M.-Z.; Wang, P.; Wang, X. L.; Watanabe, Y.; Won, E.; Yabsley, B. D.; Yamaguchi, A.; Yamashita, Y.; Yamauchi, M.; Zhang, Z. P.; Zhilich, V.; Zhulanov, V.; Zupanc, A.; Zyukova, O.

    2008-02-01

    Using 462fb-1 of e+e- annihilation data recorded by the Belle detector, we report the first observation of the decay Ds1(2536)+?D+?-K+. The ratio of branching fractions (B(Ds1(2536)+?D+?-K+))/(B(Ds1(2536)+?D*+K0)) is measured to be (3.27±0.18±0.37)%. We also study the angular distributions in the Ds1(2536)+?D*+KS0 decay and measure the ratio of D- and S-wave amplitudes. The S-wave dominates, with a partial width of ?S/?total=0.72±0.05±0.01.

  19. CHANDRA OBSERVATIONS OF NGC 4342, AN OPTICALLY FAINT, X-RAY GAS-RICH EARLY-TYPE GALAXY

    SciTech Connect

    Bogdan, Akos; Forman, William R.; Kraft, Ralph P.; Jones, Christine; Randall, Scott W.; Li Zhiyuan; Nulsen, Paul E. J.; Vikhlinin, Alexey; Blom, Christina; Zhang Zhongli; Zhuravleva, Irina; Churazov, Eugene; Schindler, Sabine

    2012-08-10

    Chandra x-ray observations of NGC 4342, a low-stellar mass (M{sub K} = -22.79 mag) early-type galaxy, show luminous, diffuse x-ray emission originating from hot gas with temperature of kT {approx} 0.6 keV. The observed 0.5-2 keV band luminosity of the diffuse x-ray emission within the D{sub 25} ellipse is L{sub 0.5-2keV} = 2.7 Multiplication-Sign 10{sup 39} erg s{sup -1}. The hot gas has a significantly broader distribution than the stellar light, and shows strong hydrodynamic disturbances with a sharp surface brightness edge to the northeast and a trailing tail. We identify the edge as a cold front and conclude that the distorted morphology of the hot gas is produced by ram pressure as NGC 4342 moves through external gas. From the thermal pressure ratios inside and outside the cold front, we estimate the velocity of NGC 4342 and find that it moves supersonically (M {approx} 2.6) toward the northeast. Outside the optical extent of the galaxy, we detect {approx}17 bright (L{sub 0.5-8keV} > or approx. 3 x 10{sup 37} erg s{sup -1}) excess x-ray point sources. The excess sources are presumably LMXBs located in metal-poor globular clusters (GCs) in the extended dark matter halo of NGC 4342. Based on the number of excess sources and the average frequency of bright LMXBs in GCs, we estimate that NGC 4342 may host roughly 850-1700 GCs. In good agreement with this, optical observations hint that NGC 4342 may harbor 1200 {+-} 500 GCs. This number corresponds to a GC specific frequency of S{sub N} = 19.9 {+-} 8.3, which is among the largest values observed in full-size galaxies.

  20. The 3-D effects in the long-term solar wind speed rise observed by Voyager 2 in early 1994

    NASA Technical Reports Server (NTRS)

    Pizzo, V. J.; Paularena, K. I.; Richardson, J. D.; Lazarus, A. J.; Belcher, J. W.

    1995-01-01

    In early 1994, Voyager 2 at 42-43 AU near heliolatitude 10 deg S observed over a period of approximately 100 days a remarkable sequence of quasi-recurrent stream fronts, wherein the background (ambient) speed rose steadily from approximately 450 to approximately 550 km/s while the mean period of the streams decreased from the usual 25 days down to approximately 20 days. A qualitative explanation for this effect can be derived from IMP observations, which show that the amplitude of the stream structure at 1 AU increased monotonically in late 1993, concurrent with major secular evolution in the corona. The reduction in period, then, amounts to a doppler shift due to the progressive overtaking of successively faster streams in the sequence. Attempts to model this process quantitatively with 1-D dynamic simulations falter on three accounts: (1) the reduction in period is overestimated, (2) the simulation predicts many more fronts surviving to 43 AU than are observed by Voyager; (3) the density variations are much too large. It is argued that inclusion of the 3-D geometry in the simulation would resolve most all these shortcomings. Using a series of calculations executed with 1-D, 2-D, and 3-D MHD models of hypothetical tilted-dipole flows, we show that: (1) the radial propagation velocities of 3-D fronts are less than those of 1-D or 2-D fronts, owing to the tilt of (and increased shearing across) the interaction surfaces hence the overtaking rate of successive streams is reduced; (2) in a tilted-dipole geometry, the reverse fronts should largely disappear from the equatorial plane by 43 AU, effectively halving the number of fronts to be observed (see companion paper on predominance of forward fronts at Voyager); and (3) the density enhancements would be much smaller than predicted by a 1-D model.

  1. The decomposition of methyltrichlorosilane: Studies in a high-temperature flow reactor

    SciTech Connect

    Allendorf, M.D.; Osterheld, T.H.; Melius, C.F.

    1994-01-01

    Experimental measurements of the decomposition of methyltrichlorosilane (MTS), a common silicon carbide precursor, in a high-temperature flow reactor are presented. The results indicate that methane and hydrogen chloride are major products of the decomposition. No chlorinated silane products were observed. Hydrogen carrier gas was found to increase the rate of MTS decomposition. The observations suggest a radical-chain mechanism for the decomposition. The implications for silicon carbide chemical vapor deposition are discussed.

  2. The combination of high sensitivity troponin T and copeptin facilitates early rule-out of ACS: a prospective observational study

    PubMed Central

    2013-01-01

    Background The combination of the new high sensitivity troponin T (hsTnT) assays and copeptin, a biomarker of endogenous stress, has been suggested to have the potential of early rule-out of acute coronary syndrome (ACS). The aim of this study was to examine the ability of this combination to rule out ACS in patients presenting with chest pain and to compare the diagnostic performance to hsTnT alone. Method In this prospective observational study, patients with chest pain admitted for observation were consecutively included. Patients presenting with ST elevation were excluded. Copeptin and hsTnT were analyzed at admission and hsTnT was thereafter determined approximately every 3rd hour as long as clinically indicated. The follow-up period was 60 days. A combined primary endpoint of ACS, non-elective percutanous coronary intervention, non-elective coronary artery bypass surgery and death of all causes was used. Results 478 patients were included. 107 (22%) patients were diagnosed with ACS during hospital stay. 70 (14%) had non-ST-segment elevation myocardial infarction (NSTEMI) and 37 (8%) had unstable angina pectoris (UAP). The combination of hsTnT >14 ng/L or copeptin ?14 pmol/L at admission identified ACS with a higher sensitivity than hsTnT alone: 0.83 (95% confidence interval (CI): 0.74-0.89) versus 0.69 (95% CI: 0.59-0.77), p <0.001. Negative predictive values (NPV) 91% (95% CI: 86-94) versus 89% (95% CI: 84-92). A repeated hsTnT analyzed 3-4 hours after admission resulted in a sensitivity of: 0.77 (95% CI: 0.65-0.86), p =0.031 for comparison with the combination analyzed at admission. Conclusions In patients presenting with chest pain admitted for observation, the combination of hsTnT and copeptin analyzed at admission had a significantly higher sensitivity to diagnose ACS than hsTnT alone. We report a sensitivity of 83% and a NPV of 91% for the combination of hsTnT and copeptin and we conclude that biomarkers alone are not sufficient to rule out ACS. However, the combination of hsTnT and copeptin seems to have a significantly higher sensitivity to identify ACS than a repeated hsTnT test, and thus enables an earlier risk stratification of chest pain patients. This can be time-saving and beneficial for the individual patient by contributing to early decisions on treatment, need of further assessment and level of care. PMID:23777442

  3. HF radar observations of Pc 5 field line resonances in the midnight/early morning MLT sector

    SciTech Connect

    Ruohoniemi, J.M.; Greenwald, R.A.; Baker, K.B. ); Samson, J.C. )

    1991-09-01

    On a number of occasions The Johns Hopkins University/Applied Physics Laboratory HF radar at Goose Bay, Labrador, has observed the effects of field line resonances on the drift velocities of irregularities in the F region of the high-latitude ionosphere. One of the most interesting sets of resonances occurs near midnight MLT and may be associated with shear in the convective flow in the magnetotail. This paper discusses in detail a particularly clear example which shows field line resonance equatorward of a region of shear flow in the early morning sector. The motions were predominantly in the geomagnetic east-west direction, indicating north-south electric fields. As expected of field line resonance pulsations, these oscillations had pronounced peaks in their latitudinal power distribution. The pulsations could occur simultaneously but remained distinct as the latitude of peak response was observed to vary inversely with the frequency of the pulsation. The authors interpret these features in terms of field line resonance theory and discuss the possible sources of the pulsation energy.

  4. Isothermal decomposition of gamma-irradiated dysprosium acetate

    NASA Astrophysics Data System (ADS)

    Mahfouz, R. M.; Al-Shehri, S. M.; Monshi, M. A. S.; Abd El-Salam, N. M.

    Isothermal decomposition of un-irradiated and pre-gamma-irradiated dysprosium acetate [Dy(CH3COO)(3)] has been investigated at different temperatures between 603-623 K. Irradiation was observed to enhance the rate of decomposition without modifying the mechanism of the thermal decomposition. Thermal decomposition of dysposium acetate is shown to proceed by a nucleation and growth mechanism (Avarmi-Erofe'ev equation) both for un-irradiated and pre-gamma-irradiated samples. The enhancement of the decomposition was found to increase with an increase in the gamma-ray dose applied to the sample and may be attributed to an increase in point defects and formation of additional nucleation centers generated in the host lattice. Thermodynamic values of the main decomposition process were calculated and evaluated.

  5. Early-type Galaxies at Intermediate Redshift Observed with Hubble Space Telescope WFC3: Perspectives on Recent Star Formation

    NASA Astrophysics Data System (ADS)

    Rutkowski, Michael J.; Jeong, Hyunjin; Cohen, Seth H.; Kaviraj, Sugata; Windhorst, Rogier A.; Ryan, Russell E., Jr.; Koekemoer, Anton; Yi, Sukyoung K.; Hathi, Nimish P.; Dopita, Michael A.

    2014-12-01

    We present an analysis of the stellar populations of 102 visually selected early-type galaxies (ETGs) with spectroscopic redshifts (0.35 lsim z lsim 1.5) from observations in the Early Release Science program with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). We fit one- and two-component synthetic stellar models to the ETGs UV-optical-near-IR spectral energy distributions and find that a large fraction (~40%) are likely to have experienced a minor (fYC lsim 10% of stellar mass) burst of recent (tYC lsim 1 Gyr) star formation. The measured age and mass fraction of the young stellar populations do not strongly trend with measurements of galaxy morphology. We note that massive (M > 1010.5 M ?) recent star-forming ETGs appear to have larger sizes. Furthermore, high-mass, quiescent ETGs identified with likely companions populate a distinct region in the size-mass parameter space, in comparison with the distribution of massive ETGs with evidence of recent star formation (RSF). We conclude that both mechanisms of quenching star formation in disk-like ETGs and (gas-rich, minor) merger activity contribute to the formation of young stars and the size-mass evolution of intermediate redshift ETGs. The number of ETGs for which we have both HST WFC3 panchromatic (especially UV) imaging and spectroscopically confirmed redshifts is relatively small, therefore, a conclusion about the relative roles of both of these mechanisms remains an open question.

  6. Early-type galaxies at intermediate redshift observed with Hubble space telescope WFC3: perspectives on recent star formation

    SciTech Connect

    Rutkowski, Michael J.; Jeong, Hyunjin; Yi, Sukyoung K.; Cohen, Seth H.; Windhorst, Rogier A.; Kaviraj, Sugata; Ryan, Russell E. Jr.; Koekemoer, Anton; Hathi, Nimish P.; Dopita, Michael A.

    2014-12-01

    We present an analysis of the stellar populations of 102 visually selected early-type galaxies (ETGs) with spectroscopic redshifts (0.35 ? z ? 1.5) from observations in the Early Release Science program with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). We fit one- and two-component synthetic stellar models to the ETGs UV-optical-near-IR spectral energy distributions and find that a large fraction (?40%) are likely to have experienced a minor (f{sub YC} ? 10% of stellar mass) burst of recent (t{sub YC} ? 1 Gyr) star formation. The measured age and mass fraction of the young stellar populations do not strongly trend with measurements of galaxy morphology. We note that massive (M > 10{sup 10.5} M {sub ?}) recent star-forming ETGs appear to have larger sizes. Furthermore, high-mass, quiescent ETGs identified with likely companions populate a distinct region in the size-mass parameter space, in comparison with the distribution of massive ETGs with evidence of recent star formation (RSF). We conclude that both mechanisms of quenching star formation in disk-like ETGs and (gas-rich, minor) merger activity contribute to the formation of young stars and the size-mass evolution of intermediate redshift ETGs. The number of ETGs for which we have both HST WFC3 panchromatic (especially UV) imaging and spectroscopically confirmed redshifts is relatively small, therefore, a conclusion about the relative roles of both of these mechanisms remains an open question.

  7. Environmental effects of solar-thermal power systems: ecological observations during early testing of the Barstow 10-MWe pilot STPS

    SciTech Connect

    Turner, F.B.

    1982-11-01

    Environmental measurements were continued at Solar One during 1982, while final steps in construction and early testing were carried out. Measurements of sand depths downwind (east) of the heliostat field indicated that some of the sand blown off the field (most of it between September 1979 and March 1980) has been carried farther east, reducing sand depths somewhat in areas just east of the field. Observations of birds between March and June 1982 revealed that (1) the natural avifauna of the field has been altered, although the area is still used for feeding by some icterids (larks, blackbirds) and aerial insectivores (swallows, swifts); (2) of 15 bird casualties ascribable to the presence and/or operation of Solar One, 12 followed collisions with heliostats, three resulted from incineration in heliostat beams; (3) the central receiver tower does not appear to be a source of mortality. Numbers of rodents (particularly kangaroo rats) trapped in areas downwind of the site declined steadily between 1978 and 1982 in areas both clost to the field and as far east as 600 m from the fence. The most likely interpretation of these changes is a reduction in reproductivity and/or early survival caused by four consecutive years (1978, 1979, 1980, 1981) of suboptimal autumn rainfall. Micrometeorological measurements in areas downwind of Solar One showed small effects on air temperatures (<0.5/sup 0/C), wind speeds (<0.4 m/sec), and evaporation rates (<1.5 ml/hr).Effects were detected only in areas 100 to 190 m from the east perimeter fence. Because these differences are so small, relative to natural heterogeneities, the effects of Solar One on rates of evaporation, air temperatures and wind speed will not affect the downwind biological community. The relavance of these findings to construction of a larger solar thermal power plant (e.g., Solar 100) are considered.

  8. Biological characterization and selection criteria of adjuvant chemotherapy for early breast cancer: experience from the Italian observational NEMESI study

    PubMed Central

    2012-01-01

    Background International treatment guidelines recommend administration of adjuvant chemotherapy in early breast cancer based on clinical, prognostic and predictive parameters. Methods An observational study (NEMESI) was conducted in 63 Italian oncology centres in patients with early breast cancer. Age, performance status, concomitant disease, menopausal status, histology, tumor dimension (pT), axillary lymph node status (pN), grading (G), estrogen and progesterone receptor (ER and PgR), proliferative index (ki67 or MIB-1), human epidermal growth factor receptor 2 (HER2) and type of adjuvant treatment were recorded. The primary objective of the study was to define parameters influencing the decision to prescribe adjuvant chemotherapy and the type of chemotherapy. Results Data for 1894 patients were available. 69.0% postmenopausal, 67.0% pT1, 22.3% pTmic/pT1a/pT1b, 61.0% pN0, 48.7% luminal A, 18.1% luminal B, 16.1% HER2 positive, 8.7% triple negative, 8.4% unknown. 57.8% received adjuvant chemotherapy: 38.1% of luminal A, 67.3% luminal B, 88.2% HER2-positive, 97.6% triple negative. Regimens administered: 9.1% CMF-like, 48.8% anthracyclines, 38.4% anthracyclines plus taxanes, 3.7% taxanes alone. Increasing pT/pN and, marginally, HER2-positive were associated with the prescription of anthracyclines plus taxanes. Suboptimal schedules (CMF-like or AC/EC or FEC-75) were prescribed in 37.3% receiving chemotherapy, even in HER2-positive and triple negative disease (36.5% and 34.0%, respectively). Conclusions This study showed an overprescription of adjuvant chemotherapy for early breast cancer, particularly referred to luminal A. pT, pN and, marginally, HER2 were the principal determinants for the choice of chemotherapy type. Suboptimal chemotherapy regimens were adopted in at least one third of HER2-positve and triple negative. PMID:22672524

  9. Decomposing Nekrasov Decomposition

    E-print Network

    A. Morozov; Y. Zenkevich

    2015-10-07

    AGT relations imply that the four-point conformal block admits a decomposition into a sum over pairs of Young diagrams of essentially rational Nekrasov functions - this is immediately seen when conformal block is represented in the form of a matrix model. However, the q-deformation of the same block has a deeper decomposition - into a sum over a quadruple of Young diagrams of a product of four topological vertices. We analyze the interplay between these two decompositions, their properties and their generalization to multi-point conformal blocks. In the latter case we explain how Dotsenko-Fateev all-with-all (star) pair "interaction" is reduced to the quiver model nearest-neighbor (chain) one. We give new identities for q-Selberg averages of pairs of generalized Macdonald polynomials. We also translate the slicing invariance of refined topological strings into the language of conformal blocks and interpret it as abelianization of generalized Macdonald polynomials.

  10. Decomposing Nekrasov Decomposition

    E-print Network

    Morozov, A

    2015-01-01

    AGT relations imply that the four-point conformal block admits a decomposition into a sum over pairs of Young diagrams of essentially rational Nekrasov functions - this is immediately seen when conformal block is represented in the form of a matrix model. However, the q-deformation of the same block has a deeper decomposition - into a sum over a quadruple of Young diagrams of a product of four topological vertices. We analyze the interplay between these two decompositions, their properties and their generalization to multi-point conformal blocks. In the latter case we explain how Dotsenko-Fateev all-with-all (star) pair "interaction" is reduced to the quiver model nearest-neighbor (chain) one. We give new identities for q-Selberg averages of pairs of generalized Macdonald polynomials. We also translate the slicing invariance of refined topological strings into the language of conformal blocks and interpret it as abelianization of generalized Macdonald polynomials.

  11. Preliminary evidence of early bone resorption in a sheep model of acute burn injury: an observational study

    PubMed Central

    Xie, Yixia; Qin, Yi-Xian; Lin, Liangjun; Hu, Minyi; Enkhbaatar, Perenlei; Bonewald, Lynda F.

    2015-01-01

    Treatment with bisphosphonates within the first 10 days of severe burn injury completely prevents bone loss. We therefore postulated that bone resorption occurs early post burn and is the primary explanation for acute bone loss in these patients. Our objective was to assess bone for histological and biomechanical evidence of early resorption post burn. We designed a randomized controlled study utilizing a sheep model of burn injury. Three sheep received a 40 % total body surface area burn under isoflurane anesthesia, and three other sheep received cotton-smoke inhalation and served as control. Burned sheep were killed 5 days post procedure and controls were killed 2 days post procedure. Backscatter scanning electron microscopy was performed on iliac crests obtained immediately postmortem along with quantitative histomorphometry and compression testing to determine bone strength (Young’s modulus). Blood ionized Ca was also determined in the first 24 h post procedure as was urinary CTx. Three of three sheep killed at 5 days had evidence of scalloping of the bone surface, an effect of bone resorption, whereas none of the three sheep killed at 2 days post procedure had scalloping. One of the three burned sheep killed at 5 days showed quantitative doubling of the eroded surface and halving of the bone volume compared to sham controls. Mean values of Young’s modulus were approximately one third lower in the burned sheep killed at 5 days compared to controls, p = 0.08 by unpaired t test, suggesting weaker bone. These data suggest early post-burn bone resorption. Urine CTx normalized to creatinine did not differ between groups at 24 h post procedure because the large amounts of fluids received by the burned sheep may have diluted urine creatinine and CTx and because the urine volume produced by the burned sheep was threefold that of the controls. We calculated 24 h urinary CTx excretion, and with this calculation CTx excretion/24 h in the burned sheep was nearly twice that of the controls. Moreover, whole blood ionized Ca measured at 3- to 6-h intervals over the first 24 h in both burn and control sheep showed a 6 % reduction versus baseline in the burned sheep with <1 % reduction in the control animals. This sheep model was previously used to demonstrate upregulation of the parathyroid calcium-sensing receptor within the timeframe of the present study. Because both early bone resorption, supported by this study, and calcium-sensing receptor upregulation, consistent with the observed reduction in blood ionized Ca, are mediated by proinflammatory cytokines that are present as part of the post-burn systemic inflammatory response, we may postulate that post-burn upregulation of the parathyroid calcium-sensing receptor may be an adaptive response to clear the blood of excess calcium liberated by cytokine-mediated bone resorption. PMID:23784552

  12. Optimal domain decomposition strategies

    NASA Technical Reports Server (NTRS)

    Yoon, Yonghyun; Soni, Bharat K.

    1995-01-01

    The primary interest of the authors is in the area of grid generation, in particular, optimal domain decomposition about realistic configurations. A grid generation procedure with optimal blocking strategies has been developed to generate multi-block grids for a circular-to-rectangular transition duct. The focus of this study is the domain decomposition which optimizes solution algorithm/block compatibility based on geometrical complexities as well as the physical characteristics of flow field. The progress realized in this study is summarized in this paper.

  13. First Stages of the Formation of the South Seasonal Cap in Early Southern Winter as Observed by OMEGA/Mex

    NASA Astrophysics Data System (ADS)

    Langevin, Y.; Vincendon, M.; Bibring, J.-P.; Gondet, B.; Poulet, F.

    2010-05-01

    Observations in the visible [1] demonstrated that the retreat of the southern seasonal is very asymmetrical from Ls 230° to Ls 300°, ice extending much further North over a range of longitudes (270° E to 0° E) corresponding to the "bright cap". Observations by TES demonstrated that the bright regions corresponding to the visible cap are at the equilibrium temperature of CO2 ice, as well as the cryptic region, which exhibits low albedos (0.2 - 0.25) close to mid southern spring (Ls 225°). Observations by OMEGA/Mex have Mars Express have demonstrated that the Southern seasonal cap is indeed spectrally dominated by CO2 ice [3, 4]. The low albedo of the cryptic region results from dust contamination on the surface [3] most likely linked to a venting process [5] when CO2 ice sublimates in contact with the underlying surface. OMEGA observed that the very high albedos are linked to large equivalent grain sizes on the bright cap (270°E to 0°E) [4]. These characteristics have been associated with global climate evolution models [6, 7] with a major role played by the two large southern basins, Hellas and Argyre, in the circulation patterns [6]. A possible interpretation of the long lasting cap over the "bright cap" range of longitudes is that the CO2 deposit on the surface is initiated by the sedimentation of small CO2 ice grains or H2O ice grains on the surface followed by the condensation of a layer CO2 directly from the atmosphere. If this is the case, the surface underlying the bright cap regions is protected from photons penetrating the overlying large-grained CO2 layer, which inhibits the venting process, delaying the sublimation of the CO2 ice layer until late spring. Observations by OMEGA close to the southern terminator in early winter (Ls 15°) at high latitudes (70°) obtained in April 2004 and November 2009 correspond to very high incidences (~ 85° or more). This requires a careful evaluation of the aerosol contribution, at the limit of the range of validity of a plane-parallel model [8], and a 3-D model taking into account the curvature of the planet [9]. The first conclusions are that the optical depth of dust is highly variable both spatially and temporally. At longitudes corresponding to the bright cap (e.g. 350° - 0°), the retrieved surface albedos are very high (60% or more), with a spectral signature corresponding to nearly pure, relatively fine-grained CO2 ice (H2O ice content < 10 ppm). High optical depths correspond to very low contrast related to topography. In such regions, the CO2 ice signature is still observed, with a strong blue slope indicating that very fine-grained aerosols (0.5 µm in size or less) are present. OMEGA/Mex observations support the formation of ice grains in the atmosphere before sedimentation early in southern winter, either from homogeneous condensation or from heterogeneous condensation on very fine grained H2O ice. These results support the concept that a thin layer of small CO2 ice grains sedimenting from the atmosphere in early southern winter is at the origin of the long-lasting "bright cap" region of the southern seasonal cap. [1] P. B. James et al. J. Geophys. Res. 84, p. 2889 (1979), [2] H. H. Kieffer et al., J. Geophys. Res. 105, p. 8263 (2000) [3] Y. Langevin et al., Nature 442, p. 831 (2006);[4] Y. Langevin et al., J. Geophys. Res. 112, E08S12 (2007) [5] H. Kieffer, J. Geophys. Res. 112, E08005 (2007); [6] A. Colaprete et al., Nature 435, p. 184 (2005) [7] F. Montmessin et al., J. Geophys. Res. 109, doi: 10.1029/2004JE002284 (2004) [8] M. Vincendon et al., J. Geophys. Res. 112, E08S13 (2007); [9] M. Vincendon and Y. Langevin, Icarus,in press

  14. UV-DROPOUT GALAXIES IN THE GOODS-SOUTH FIELD FROM WFC3 EARLY RELEASE SCIENCE OBSERVATIONS

    SciTech Connect

    Hathi, N. P.; Ryan, R. E.; Cohen, S. H.; Windhorst, R. A.; Rutkowski, M. J.; Yan, H.; McCarthy, P. J.; O'Connell, R. W.; Koekemoer, A. M.; Bond, H. E.; Balick, B.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; Kimble, R. A.; Paresce, F.; Saha, A.

    2010-09-10

    We combine new high sensitivity ultraviolet (UV) imaging from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) with existing deep HST/Advanced Camera for Surveys optical images from the Great Observatories Origins Deep Survey (GOODS) program to identify UV-dropouts, which are Lyman break galaxy (LBG) candidates at z {approx_equal} 1-3. These new HST/WFC3 observations were taken over 50 arcmin{sup 2} in the GOODS-South field as a part of the Early Release Science program. The uniqueness of these new UV data is that they are observed in three UV/optical (WFC3 UVIS) channel filters (F225W, F275W, and F336W), which allows us to identify three different sets of UV-dropout samples. We apply Lyman break dropout selection criteria to identify F225W-, F275W-, and F336W-dropouts, which are z {approx_equal} 1.7, 2.1, and 2.7 LBG candidates, respectively. We use multi-wavelength imaging combined with available spectroscopic and photometric redshifts to carefully access the validity of our UV-dropout candidates. Our results are as follows: (1) these WFC3 UVIS filters are very reliable in selecting LBGs with z {approx_equal} 2.0, which helps to reduce the gap between the well-studied z {approx}> 3 and z {approx} 0 regimes; (2) the combined number counts with average redshift z {approx_equal} 2.2 agree very well with the observed change in the surface densities as a function of redshift when compared with the higher redshift LBG samples; and (3) the best-fit Schechter function parameters from the rest-frame UV luminosity functions at three different redshifts fit very well with the evolutionary trend of the characteristic absolute magnitude, M*, and the faint-end slope, {alpha}, as a function of redshift. This is the first study to illustrate the usefulness of the WFC3 UVIS channel observations to select z {approx}< 3 LBGs. The addition of the new WFC3 on the HST has made it possible to uniformly select LBGs from z {approx_equal} 1 to z {approx_equal} 9 and significantly enhance our understanding of these galaxies using HST sensitivity and resolution.

  15. UV-dropout Galaxies in the Goods-South Field from WFC3 Early Release Science Observations

    NASA Astrophysics Data System (ADS)

    Hathi, N. P.; Ryan, R. E., Jr.; Cohen, S. H.; Yan, H.; Windhorst, R. A.; McCarthy, P. J.; O'Connell, R. W.; Koekemoer, A. M.; Rutkowski, M. J.; Balick, B.; Bond, H. E.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; Kimble, R. A.; Paresce, F.; Saha, A.; Silk, J. I.; Trauger, J. T.; Walker, A. R.; Whitmore, B. C.; Young, E. T.

    2010-09-01

    We combine new high sensitivity ultraviolet (UV) imaging from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) with existing deep HST/Advanced Camera for Surveys optical images from the Great Observatories Origins Deep Survey (GOODS) program to identify UV-dropouts, which are Lyman break galaxy (LBG) candidates at z ~= 1-3. These new HST/WFC3 observations were taken over 50 arcmin2 in the GOODS-South field as a part of the Early Release Science program. The uniqueness of these new UV data is that they are observed in three UV/optical (WFC3 UVIS) channel filters (F225W, F275W, and F336W), which allows us to identify three different sets of UV-dropout samples. We apply Lyman break dropout selection criteria to identify F225W-, F275W-, and F336W-dropouts, which are z ~= 1.7, 2.1, and 2.7 LBG candidates, respectively. We use multi-wavelength imaging combined with available spectroscopic and photometric redshifts to carefully access the validity of our UV-dropout candidates. Our results are as follows: (1) these WFC3 UVIS filters are very reliable in selecting LBGs with z ~= 2.0, which helps to reduce the gap between the well-studied z >~ 3 and z ~ 0 regimes; (2) the combined number counts with average redshift z ~= 2.2 agree very well with the observed change in the surface densities as a function of redshift when compared with the higher redshift LBG samples; and (3) the best-fit Schechter function parameters from the rest-frame UV luminosity functions at three different redshifts fit very well with the evolutionary trend of the characteristic absolute magnitude, M*, and the faint-end slope, ?, as a function of redshift. This is the first study to illustrate the usefulness of the WFC3 UVIS channel observations to select z <~ 3 LBGs. The addition of the new WFC3 on the HST has made it possible to uniformly select LBGs from z ~= 1 to z ~= 9 and significantly enhance our understanding of these galaxies using HST sensitivity and resolution.

  16. Methotrexate-associated lymphoproliferative disorders: management by watchful waiting and observation of early lymphocyte recovery after methotrexate withdrawal.

    PubMed

    Inui, Yumiko; Matsuoka, Hiroshi; Yakushijin, Kimikazu; Okamura, Atsuo; Shimada, Takaki; Yano, Shingo; Takeuchi, Mai; Ito, Mitsuhiro; Murayama, Tohru; Yamamoto, Katsuya; Itoh, Tomoo; Aiba, Keisuke; Minami, Hironobu

    2015-11-01

    No optimum treatment of iatrogenic immunodeficiency-associated lymphoproliferative disorders due to methotrexate in patients with rheumatoid arthritis (MTX-LPD) has yet been established, although MTX withdrawal is known to have a substantial effect on tumor regression. Here, we retrospectively analyzed 20 cases of MTX-LPD. Tumor shrinkage occurred in 18 of 20 cases, but only following MTX withdrawal. This tumor regression ratio was considerably better than in previous reports, and appeared due to longer "watchful waiting." Lymphocyte recovery at 2 weeks after MTX withdrawal was significantly higher in cases with tumor regression in 1 month than in those without tumor regression (p = 0.001). Median time to maximal efficacy after MTX cessation in cases without chemotherapy was 12 weeks (range 2-76). In conclusion, watchful waiting for a longer period after MTX cessation with observation of early lymphocyte recovery and uninterrupted continuation of other anti-rheumatoid drugs may be an acceptable management plan for MTX-LPD. PMID:25721751

  17. Robust Matrix Decomposition with Sparse Corruptions

    E-print Network

    de Sa, Virginia

    1 Robust Matrix Decomposition with Sparse Corruptions Daniel Hsu, Sham M. Kakade, and Tong Zhang Abstract--Suppose a given observation matrix can be decomposed as the sum of a low-rank matrix and a sparse of a sparse matrix XS and a low-rank matrix XL. For instance, in the application to PCA, XL represents

  18. Hydrazine decomposition and other reactions

    NASA Technical Reports Server (NTRS)

    Armstrong, Warren E. (Inventor); La France, Donald S. (Inventor); Voge, Hervey H. (Inventor)

    1978-01-01

    This invention relates to the catalytic decomposition of hydrazine, catalysts useful for this decomposition and other reactions, and to reactions in hydrogen atmospheres generally using carbon-containing catalysts.

  19. Cortisol Levels during the Menopausal Transition and Early Postmenopause: Observations from the Seattle Midlife Women’s Health Study

    PubMed Central

    Woods, Nancy Fugate; Mitchell, Ellen Sullivan; Smith-DiJulio, Kathleen

    2009-01-01

    Aims Cortisol levels rise among some women during the late stage of the menopausal transition, but we know little about changes in cortisol levels in relation to menopause-related factors (menopausal transition (MT) stage, urinary estrone glucuronide, testosterone, FSH), stress-related factors (epinephrine, norepinephrine, perceived stress), symptoms (hot flashes, mood, memory and sleep), social factors (income adequacy, role burden, social support, employment, parenting, and history of sexual abuse) and health-related factors (depressed mood, perceived health, physical appraisal, BMI, and smoking). Aims were to examine the influence of menopause-related factors, stress-related factors, symptoms, social, and health-related factors on cortisol levels during the menopausal transition. Methods A subset of Seattle Midlife Women’s Health Study participants who provided data during the late reproductive, early and late MT stages or early postmenopause (PM) and who were not using hormone therapy or corticosteroids (N=132 women, up to 5218 observations) including menstrual calendars for staging the MT, annual health reports, health diaries, and overnight urine specimens (assayed for cortisol, catecholamines, estrone glucuronide and FSH) between 1990 and 2005 were included. Perceived stress, symptoms, and health behaviors were assessed in a health diary. Health-related and social factors were assessed in an annual health update. Multilevel modeling was used to test effects of menopause- related and other factors on overnight cortisol levels. Results When tested with age as a measure of time, menopause-related covariates, including estrone glucuronide (E1G), FSH, and testosterone were associated with significant increases in overnight cortisol levels (p<.0001). Likewise, epinephrine and norepinephrine were each associated significantly with overnight cortisol levels (p<.0001). In multivariate analyses, E1G, FSH, and testosterone constituted the best set of predictors. Conclusions Overnight cortisol levels during the MT were associated with E1G, testosterone, and FSH levels. In addition, they were significantly and positively associated with epinephrine and norepinephrine. MT stage, symptoms, and social, stress-related, and health-related factors had little relationship to overnight cortisol levels when other biological indicators were considered. PMID:19322116

  20. Fractional Adomian Decomposition Method

    E-print Network

    Guo-cheng Wu; Ji-Huan He

    2013-04-24

    A fractional Adomian decomposition method for fractional nonlinear differential equations is proposed. The iteration procedure is based on Jumarie's fractional derivative. An example is given to elucidate the solution procedure, and the results are compared with the exact solution, revealing high accuracy and efficiency.

  1. Decomposition of geometric perturbations

    E-print Network

    Roman V. Buniy; Thomas W. Kephart

    2008-11-12

    For an infinitesimal deformation of a Riemannian manifold, we prove that the scalar, vector, and tensor modes in decompositions of perturbations of the metric tensor, the scalar curvature, the Ricci tensor, and the Einstein tensor decouple if and only if the manifold is Einstein. Four-dimensional space-time satisfying the condition of the theorem is homogeneous and isotropic. Cosmological applications are discussed.

  2. Soil-litter mixing accelerates decomposition in a Chihuahuan Desert grassland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decomposition models typically under-predict decomposition relative to observed rates in drylands. This discrepancy indicates a significant gap in our mechanistic understanding of carbon and nutrient cycling in these systems. Recent research suggests that certain drivers of decomposition that are of...

  3. Scaling & Decomposition of Digital Designs

    E-print Network

    ! Scaling & Decomposition of Digital Designs Larry Sass CNC Technologies Digital Designer Self Complexity in the Digital Age" William J. Mitchell*" Scaling & Decomposition" Challenge" Skidmore Owings Design 1/8" - 3.1 mm Product 1/2" - 12.7 mm #12;Procedural Decomposition 2005 CBA 1 2 3 5 4 #12;A

  4. Primary Decomposition: Algorithms and Comparisons

    E-print Network

    Greuel, Gert-Martin

    Primary Decomposition: Algorithms and Comparisons Wolfram Decker 1 Gert­Martin Greuel 2 and Gerhard Kaiserslautern 1 Introduction Primary decomposition of an ideal in a polynomial ring over a field belongs to the decomposition of an affine variety into irreducible components and is, therefore, also an important geometric

  5. The Size Evolution of Passive Galaxies: Observations from the Wide-Field Camera 3 Early Release Science Program

    NASA Astrophysics Data System (ADS)

    Ryan, R. E., Jr.; McCarthy, P. J.; Cohen, S. H.; Yan, H.; Hathi, N. P.; Koekemoer, A. M.; Rutkowski, M. J.; Mechtley, M. R.; Windhorst, R. A.; O'Connell, R. W.; Balick, B.; Bond, H. E.; Bushouse, H.; Calzetti, D.; Crockett, R. M.; Disney, M.; Dopita, M. A.; Frogel, J. A.; Hall, D. N. B.; Holtzman, J. A.; Kaviraj, S.; Kimble, R. A.; MacKenty, J.; Mutchler, M.; Paresce, F.; Saha, A.; Silk, J. I.; Trauger, J.; Walker, A. R.; Whitmore, B. C.; Young, E.

    2012-04-01

    We present the size evolution of passively evolving galaxies at z ~ 2 identified in Wide-Field Camera 3 imaging from the Early Release Science program. Our sample was constructed using an analog to the passive BzK galaxy selection criterion, which isolates galaxies with little or no ongoing star formation at z >~ 1.5. We identify 30 galaxies in ~40 arcmin2 to H < 25 mag. By fitting the 10-band Hubble Space Telescope photometry from 0.22 ?m <~ ?obs <~ 1.6 ?m with stellar population synthesis models, we simultaneously determine photometric redshift, stellar mass, and a bevy of other population parameters. Based on the six galaxies with published spectroscopic redshifts, we estimate a typical redshift uncertainty of ~0.033(1 + z). We determine effective radii from Sérsic profile fits to the H-band image using an empirical point-spread function. By supplementing our data with published samples, we propose a mass-dependent size evolution model for passively evolving galaxies, where the most massive galaxies (M * ~ 1011 M ?) undergo the strongest evolution from z ~ 2 to the present. Parameterizing the size evolution as (1 + z)-?, we find a tentative scaling of ? ? (- 0.6 ± 0.7) + (0.9 ± 0.4)log (M */109 M ?), where the relatively large uncertainties reflect the poor sampling in stellar mass due to the low numbers of high-redshift systems. We discuss the implications of this result for the redshift evolution of the M *-Re relation for red galaxies. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  6. An observation of homogeneous and heterogeneous catalysis processes in the decomposition of H sub 2 O sub 2 over MnO sub 2 and Mn(OH) sub 2

    SciTech Connect

    Jiang, S.P.; Ashton, W.R.; Tseung, A.C.C. )

    1991-09-01

    The kinetics of peroxide decomposition by manganese dioxide (MnO{sub 2}) and manganese hydroxide (Mn(OH){sub 2}) have been studied in alkaline solutions. The activity for peroxide decomposition on Mn(OH){sub 2} was generally higher than MnO{sub 2} and the kinetics for the decomposition of H{sub 2}O{sub 2} were first-order in the case of MnO{sub 2} catalysts, but 1.3-order for Mn(OH){sub 2} catalysts. It is suggested that H{sub 2}O{sub 2} is mainly homogeneously decomposed by Mn{sup 2+} ions (in the form of HMnO{sub 2}{sup {minus}} ions in concentrated alkaline solutions) dissolved in the solution in the case of Mn(OH){sub 2}. Compared with the results reported for the decomposition of H{sub 2}O{sub 2} in the presence of 1 ppm Co{sup 2+} ions, it is concluded that the kinetics of the homogeneous decomposition of H{sub 2}O{sub 2} are directly influenced by the concentration of the active species in the solution.

  7. Social-Emotional Well-Being and Resilience of Children in Early Childhood Settings--PERIK: An Empirically Based Observation Scale for Practitioners

    ERIC Educational Resources Information Center

    Mayr, Toni; Ulich, Michaela

    2009-01-01

    Compared with the traditional focus on developmental problems, research on positive development is relatively new. Empirical research in children's well-being has been scarce. The aim of this study was to develop a theoretically and empirically based instrument for practitioners to observe and assess preschool children's well-being in early

  8. Swedish Religious Education at the End of the 1960s: Classroom Observations, Early Video Ethnography and the National Curriculum of 1962

    ERIC Educational Resources Information Center

    Flensner, K. Kittelmann; Larsson, G.

    2014-01-01

    The aim of this article is to present a unique corpus of film-recorded classroom observations of sixth-grade classes (age 12-13) in the Swedish cities of Gothenburg, Partille and Trollhättan in the late 1960s. The material documents how RE could be taught in Swedish schools in line with the curriculum of Lgr 62 which internationally was an early

  9. The Association between Parent Early Adult Drug Use Disorder and Later Observed Parenting Practices and Child Behavior Problems: Testing Alternate Models

    ERIC Educational Resources Information Center

    Bailey, Jennifer A.; Hill, Karl G.; Guttmannova, Katarina; Oesterle, Sabrina; Hawkins, J. David; Catalano, Richard F.; McMahon, Robert J.

    2013-01-01

    This study tested the association between parent illicit drug use disorder (DUD) in early adulthood and observed parenting practices at ages 27-28 and examined the following 3 theoretically derived models explaining this link: (a) a disrupted parent adult functioning model,(b) a preexisting parent personality factor model, and (c) a disrupted…

  10. Observed Differences between Early Childhood Programs in the U.S. and Korea: Reflections of "Developmentally Appropriate Practices" in Two Cultural Contexts

    ERIC Educational Resources Information Center

    Clarke-Stewart, K. Alison; Lee, Young; Allhusen, Virginia D.; Kim, Myoung Soon; McDowell, David J.

    2006-01-01

    Ninety children from South Korea and 119 children from the United States were observed in early childhood programs, and differences in classroom environments and teachers' and children's behavior in the two countries were identified. In both countries, there was evidence that preschool education is guided by ideas about "developmentally…

  11. Use of the Earth Observing One (EO-1) Satellite for the Namibia SensorWeb Flood Early Warning Pilot

    NASA Technical Reports Server (NTRS)

    Mandl, Daniel; Frye, Stuart; Cappelaere, Pat; Handy, Matthew; Policelli, Fritz; Katjizeu, McCloud; Van Langenhove, Guido; Aube, Guy; Saulnier, Jean-Francois; Sohlberg, Rob; Silva, Julie; Kussul, Nataliia; Skakun, Sergii; Ungar, Stephen; Grossman, Robert

    2012-01-01

    The Earth Observing One (EO-1) satellite was launched in November 2000 as a one year technology demonstration mission for a variety of space technologies. After the first year, it was used as a pathfinder for the creation of SensorWebs. A SensorWeb is the integration of variety of space, airborne and ground sensors into a loosely coupled collaborative sensor system that automatically provides useful data products. Typically, a SensorWeb is comprised of heterogeneous sensors tied together with a messaging architecture and web services. Disasters are the perfect arena to use SensorWebs. One SensorWeb pilot project that has been active since 2009 is the Namibia Early Flood Warning SensorWeb pilot project. The Pilot Project was established under the auspices of the Namibian Ministry of Agriculture Water and Forestry (MAWF)/Department of Water Affairs, the Committee on Earth Observing Satellites (CEOS)/Working Group on Information Systems and Services (WGISS) and moderated by the United Nations Platform for Space-based Information for Disaster Management and Emergency Response (UN-SPIDER). The effort began by identifying and prototyping technologies which enabled the rapid gathering and dissemination of both space-based and ground sensor data and data products for the purpose of flood disaster management and water-borne disease management. This was followed by an international collaboration to build small portions of the identified system which was prototyped during that past few years during the flood seasons which occurred in the February through May timeframe of 2010 and 2011 with further prototyping to occur in 2012. The SensorWeb system features EO-1 data along with other data sets from such satellites as Radarsat, Terra and Aqua. Finally, the SensorWeb team also began to examine the socioeconomic component to determine the impact of the SensorWeb technology and how best to assist in the infusion of this technology in lesser affluent areas with low levels of basic infrastructure. This paper provides an overview of these efforts, highlighting the EO-1 usage in this SensorWeb.

  12. Narratability and Cluster Decomposition

    E-print Network

    Simon Judes

    2010-02-08

    Recently David Albert presented an argument that relativistic quantum theories are non-narratable. That is, specifying the state on every space-like hypersurface in a given foliation of space-time is not in general sufficient to determine the states on other hypersurfaces, so the history of the universe cannot be told as a narration of states at successive times. We show that the system Albert examined to arrive at this conclusion violates cluster decomposition of the S-matrix, a locality requirement satisfied by relativistic quantum field theories. We formulate the general requirements for a system to display non-narratability, and argue that a large class of systems satisfying them violate the cluster decomposition principle.

  13. Decomposition of quantum gates

    E-print Network

    Chi-Kwong Li; Diane Pelejo

    2013-12-05

    A recurrence scheme is presented to decompose an $n$-qubit unitary gate to the product of no more than $N(N-1)/2$ single qubit gates with small number of controls, where $N = 2^n$. Detailed description of the recurrence steps and formulas for the number of $k$-controlled single qubit gates in the decomposition are given. Comparison of the result to a previous scheme is presented, and future research directions are discussed.

  14. Multicriteria approximation through decomposition

    SciTech Connect

    Burch, C.; Krumke, S.; Marathe, M.; Phillips, C.; Sundberg, E.

    1998-06-01

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of their technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. Their method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) the authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing; (2) they also show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  15. Multicriteria approximation through decomposition

    SciTech Connect

    Burch, C. |; Krumke, S.; Marathe, M.; Phillips, C.; Sundberg, E. |

    1997-12-01

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of the technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. The method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) The authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing. (2) They show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  16. Discrete Optimization in Early Vision DISCRETE OPTIMIZATION IN EARLY VISION

    E-print Network

    Lunds Universitet

    Discrete Optimization in Early Vision #12;#12;DISCRETE OPTIMIZATION IN EARLY VISION MODEL.4 Discussion 7 Parallel and Distributed Graph Cuts 7.1 Previous Approaches to Graph Cuts in Vision 7.2 Decomposition of Graphs 7.3 Experiments on a Single Machine 7.4 Splitting across Different Machines 7

  17. A Fantastic Decomposition: Unsettling the Fury of Having to Wait

    ERIC Educational Resources Information Center

    Holmes, Rachel

    2012-01-01

    This article draws on data from a single element of a larger project, which focused on the issue of "how children develop a reputation as "naughty" in the early years classroom." The author draws attention to the (in)corporeal (re)formation of the line in school, undertaking a decomposition of the topological spaces of research/art/education. She…

  18. Observation of Early Cleavage in Animal Development: A Simple Technique for Obtaining the Eggs of Rhabditis (Nematoda)

    ERIC Educational Resources Information Center

    Hinchliffe, J. R.

    1973-01-01

    Outlines the advantages of using the readily available eggs of the nematode Rhabditis in studying the early cleavage stages of animal development. Discusses the identification and life history of Rhabditis, how to culture and examine the organism, the cleavage stages and cell lineage, and sources of visual aids. (JR)

  19. Polymerization-induced spinodal decomposition of ethylene glycol/phenolic resin solutions under electric fields

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Qiao, Guanjun

    2013-10-01

    Temporal evolution of polymerization-induced spinodal decomposition (PISD) under electric fields was investigated numerically in ethylene glycol/phenolic resin solutions with different initial composition. A model composed of the nonlinear Cahn-Hilliard-Cook equation for spinodal decomposition and a rate equation for curing reaction was utilized to describe the PISD phenomenon. As initial composition varied, deformed droplet-like and aligned bi-continuous structures were observed in the presence of an electric field. Moreover, the anisotropic parameter (D), determined from the 2D-FFT power spectrum, was employed to quantitatively characterize the degree of morphology anisotropy. The value of D increased quickly in the early stage and then decreased in the intermediate stage of spinodal decomposition, which was attributed to the resistance of coarsening process to morphology deformation and the decline of electric stress caused by polymerization reaction. The results can also provide a guidance on how to control the morphology of monolithic porous polymer and carbon materials with anisotropic structures.

  20. Autocatalytic Decomposition Mechanisms in Energetic Molecular Crystals

    NASA Astrophysics Data System (ADS)

    Kuklja, Maija; Rashkeev, Sergey

    2009-06-01

    Atomic scale mechanisms of the initiation of chemical processes in energetic molecular crystals, which lead to the decomposition and ultimately to an explosive chain reaction, are still far from being understood. In this work, we investigate the onset of the initiation processes in two high explosive crystals - diamino-dinitroethylene (DADNE) and triamino- trinitrobenzene (TATB). We found that an autocatalytic decomposition mechanism is likely to take place in DADNE crystal that consists of corrugated, dashboard-shaped molecular layers. The presence of a dissociated NO2 group in the interstitial space between two layers induces a significant shear-strain between these layers, which, in turn, facilitates the further dissociation of NO2 groups from surrounding molecules through lowering the C-NO2 decomposition barrier. Unlike this, in TATB (that consists of flat, graphite-like molecular layers), an interstitial NO2 group positioned between two layers tends to produce a tensile stress (rather than a shear-strain), which leads to local molecular disorder in these layers without any significant modification of the C-NO2 decomposition barrier. The observed differences between the two materials are discussed in terms of their structural, electronic, and chemical properties.

  1. Mode decomposition evolution equations

    PubMed Central

    Wang, Yang; Wei, Guo-Wei; Yang, Siyang

    2011-01-01

    Partial differential equation (PDE) based methods have become some of the most powerful tools for exploring the fundamental problems in signal processing, image processing, computer vision, machine vision and artificial intelligence in the past two decades. The advantages of PDE based approaches are that they can be made fully automatic, robust for the analysis of images, videos and high dimensional data. A fundamental question is whether one can use PDEs to perform all the basic tasks in the image processing. If one can devise PDEs to perform full-scale mode decomposition for signals and images, the modes thus generated would be very useful for secondary processing to meet the needs in various types of signal and image processing. Despite of great progress in PDE based image analysis in the past two decades, the basic roles of PDEs in image/signal analysis are only limited to PDE based low-pass filters, and their applications to noise removal, edge detection, segmentation, etc. At present, it is not clear how to construct PDE based methods for full-scale mode decomposition. The above-mentioned limitation of most current PDE based image/signal processing methods is addressed in the proposed work, in which we introduce a family of mode decomposition evolution equations (MoDEEs) for a vast variety of applications. The MoDEEs are constructed as an extension of a PDE based high-pass filter (Europhys. Lett., 59(6): 814, 2002) by using arbitrarily high order PDE based low-pass filters introduced by Wei (IEEE Signal Process. Lett., 6(7): 165, 1999). The use of arbitrarily high order PDEs is essential to the frequency localization in the mode decomposition. Similar to the wavelet transform, the present MoDEEs have a controllable time-frequency localization and allow a perfect reconstruction of the original function. Therefore, the MoDEE operation is also called a PDE transform. However, modes generated from the present approach are in the spatial or time domain and can be easily used for secondary processing. Various simplifications of the proposed MoDEEs, including a linearized version, and an algebraic version, are discussed for computational convenience. The Fourier pseudospectral method, which is unconditionally stable for linearized the high order MoDEEs, is utilized in our computation. Validation is carried out to mode separation of high frequency adjacent modes. Applications are considered to signal and image denoising, image edge detection, feature extraction, enhancement etc. It is hoped that this work enhances the understanding of high order PDEs and yields robust and useful tools for image and signal analysis. PMID:22408289

  2. Hydrogen peroxide catalytic decomposition

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2010-01-01

    Nitric oxide in a gaseous stream is converted to nitrogen dioxide using oxidizing species generated through the use of concentrated hydrogen peroxide fed as a monopropellant into a catalyzed thruster assembly. The hydrogen peroxide is preferably stored at stable concentration levels, i.e., approximately 50%-70% by volume, and may be increased in concentration in a continuous process preceding decomposition in the thruster assembly. The exhaust of the thruster assembly, rich in hydroxyl and/or hydroperoxy radicals, may be fed into a stream containing oxidizable components, such as nitric oxide, to facilitate their oxidation.

  3. Three-pattern decomposition of global atmospheric circulation: part I—decomposition model and theorems

    NASA Astrophysics Data System (ADS)

    Hu, Shujuan; Chou, Jifan; Cheng, Jianbo

    2015-09-01

    In order to study the interactions between the atmospheric circulations at the middle-high and low latitudes from the global perspective, the authors proposed the mathematical definition of three-pattern circulations, i.e., horizontal, meridional and zonal circulations with which the actual atmospheric circulation is expanded. This novel decomposition method is proved to accurately describe the actual atmospheric circulation dynamics. The authors used the NCEP/NCAR reanalysis data to calculate the climate characteristics of those three-pattern circulations, and found that the decomposition model agreed with the observed results. Further dynamical analysis indicates that the decomposition model is more accurate to capture the major features of global three dimensional atmospheric motions, compared to the traditional definitions of Rossby wave, Hadley circulation and Walker circulation. The decomposition model for the first time realized the decomposition of global atmospheric circulation using three orthogonal circulations within the horizontal, meridional and zonal planes, offering new opportunities to study the large-scale interactions between the middle-high latitudes and low latitudes circulations.

  4. Reactive Goal Decomposition Hierarchies for On-Board Autonomy

    NASA Astrophysics Data System (ADS)

    Hartmann, L.

    2002-01-01

    As our experience grows, space missions and systems are expected to address ever more complex and demanding requirements with fewer resources (e.g., mass, power, budget). One approach to accommodating these higher expectations is to increase the level of autonomy to improve the capabilities and robustness of on- board systems and to simplify operations. The goal decomposition hierarchies described here provide a simple but powerful form of goal-directed behavior that is relatively easy to implement for space systems. A goal corresponds to a state or condition that an operator of the space system would like to bring about. In the system described here goals are decomposed into simpler subgoals until the subgoals are simple enough to execute directly. For each goal there is an activation condition and a set of decompositions. The decompositions correspond to different ways of achieving the higher level goal. Each decomposition contains a gating condition and a set of subgoals to be "executed" sequentially or in parallel. The gating conditions are evaluated in order and for the first one that is true, the corresponding decomposition is executed in order to achieve the higher level goal. The activation condition specifies global conditions (i.e., for all decompositions of the goal) that need to hold in order for the goal to be achieved. In real-time, parameters and state information are passed between goals and subgoals in the decomposition; a termination indication (success, failure, degree) is passed up when a decomposition finishes executing. The lowest level decompositions include servo control loops and finite state machines for generating control signals and sequencing i/o. Semaphores and shared memory are used to synchronize and coordinate decompositions that execute in parallel. The goal decomposition hierarchy is reactive in that the generated behavior is sensitive to the real-time state of the system and the environment. That is, the system is able to react to state and environment and in general can terminate the execution of a decomposition and attempt a new decomposition at any level in the hierarchy. This goal decomposition system is suitable for workstation, microprocessor and fpga implementation and thus is able to support the full range of prototyping activities, from mission design in the laboratory to development of the fpga firmware for the flight system. This approach is based on previous artificial intelligence work including (1) Brooks' subsumption architecture for robot control, (2) Firby's Reactive Action Package System (RAPS) for mediating between high level automated planning and low level execution and (3) hierarchical task networks for automated planning. Reactive goal decomposition hierarchies can be used for a wide variety of on-board autonomy applications including automating low level operation sequences (such as scheduling prerequisite operations, e.g., heaters, warm-up periods, monitoring power constraints), coordinating multiple spacecraft as in formation flying and constellations, robot manipulator operations, rendez-vous, docking, servicing, assembly, on-orbit maintenance, planetary rover operations, solar system and interstellar probes, intelligent science data gathering and disaster early warning. Goal decomposition hierarchies can support high level fault tolerance. Given models of on-board resources and goals to accomplish, the decomposition hierarchy could allocate resources to goals taking into account existing faults and in real-time reallocating resources as new faults arise. Resources to be modeled include memory (e.g., ROM, FPGA configuration memory, processor memory, payload instrument memory), processors, on-board and interspacecraft network nodes and links, sensors, actuators (e.g., attitude determination and control, guidance and navigation) and payload instruments. A goal decomposition hierarchy could be defined to map mission goals and tasks to available on-board resources. As faults occur and are detected the resource allocation is modified to avoid using the f

  5. Isospin fractionation : equilibrium versus spinodal decomposition

    E-print Network

    Camille Ducoin; Philippe Chomaz; Francesca Gulminelli

    2006-12-21

    This paper focuses on the isospin properties of the asymmetric nuclear-matter liquid-gas phase transition analyzed in a mean-field approach, using Skyrme effective interactions. We compare two different mechanisms of phase separation for low-density matter: equilibrium and spinodal decomposition. The isospin properties of the phases are deduced from the free-energy curvature, which contains information both on the average isospin content and on the system fluctuations. Some implications on experimentally accessible isospin observables are presented.

  6. Hydrogen iodide decomposition

    DOEpatents

    O'Keefe, Dennis R. (San Diego, CA); Norman, John H. (San Diego, CA)

    1983-01-01

    Liquid hydrogen iodide is decomposed to form hydrogen and iodine in the presence of water using a soluble catalyst. Decomposition is carried out at a temperature between about 350.degree. K. and about 525.degree. K. and at a corresponding pressure between about 25 and about 300 atmospheres in the presence of an aqueous solution which acts as a carrier for the homogeneous catalyst. Various halides of the platinum group metals, particularly Pd, Rh and Pt, are used, particularly the chlorides and iodides which exhibit good solubility. After separation of the H.sub.2, the stream from the decomposer is countercurrently extracted with nearly dry HI to remove I.sub.2. The wet phase contains most of the catalyst and is recycled directly to the decomposition step. The catalyst in the remaining almost dry HI-I.sub.2 phase is then extracted into a wet phase which is also recycled. The catalyst-free HI-I.sub.2 phase is finally distilled to separate the HI and I.sub.2. The HI is recycled to the reactor; the I.sub.2 is returned to a reactor operating in accordance with the Bunsen equation to create more HI.

  7. The early stage of formation of self-organized nanocolumns in thin films: Monte Carlo simulations versus atomic-scale observations in Ge-Mn

    SciTech Connect

    Mouton, I.; Talbot, E. Pareige, C.; Lardé, R.; Blavette, D.

    2014-02-07

    Formation kinetics of self-organized nanocolumns during epitaxial growth of a thin film composed of immiscible elements (A,B) has been investigated using Kinetic Monte Carlo simulations. Simulated nanostructures show a good agreement with those observed in Ge-Mn using Atom Probe Tomography and Transmission Electron Microscopy. Self organisation is observed although the rigid lattice simulations used do not account for misfit elastic strain. Simulations reveal that the final nanostructure, in term of number density and diameter of nanocolumns, is controlled by the early stages of growth of the film. The influence of both growth temperature and solute concentration on the nanostructure features is discussed in details.

  8. Early Anti-Pseudomonal Acquisition in Young Patients with Cystic Fibrosis: Rationale and Design of the EPIC Clinical Trial and Observational Study

    PubMed Central

    Treggiari, Miriam M; Rosenfeld, Margaret; Mayer-Hamblett, Nicole; Retsch-Bogart, George; Gibson, Ronald L.; Williams, Judy; Emerson, Julia; Kronmal, Richard A; Ramsey, Bonnie W

    2009-01-01

    Background The primary cause of morbidity and mortality in patients with cystic fibrosis (CF) is progressive obstructive pulmonary disease due to chronic endobronchial infection, particularly with Pseudomonas aeruginosa (Pa). Risk factors for and clinical impact of early Pa infection in young CF patients are less well understood. Purpose The present studies are designed to evaluate risk factors and outcomes associated with early Pa acquisition, and the benefits and harms of four anti-pseudomonal treatment regimens in young CF patients initiated after the first Pa positive respiratory culture. Methods The Early Pseudomonas Infection Control (EPIC) program consists of two studies, a randomized multicenter trial in CF patients ages 1–12 years at first isolation of Pa from a respiratory culture, and a longitudinal cohort study enrolling Pa-negative patients. Using a factorial design, trial participants are assigned for 18 months to either anti-pseudomonal treatment on a scheduled quarterly basis (cycled therapy) or based on recovery of Pa from quarterly respiratory cultures (culture-based therapy). The study drugs include inhaled tobramycin (300 mg BID) for 28 days, combined with either oral ciprofloxacin (15–20 mg/kg BID) or oral placebo for 14 days. The primary endpoints of the trial are the time to pulmonary exacerbation requiring IV antibiotics or hospitalization for respiratory symptoms, and the proportion of patients with new Pa-positive respiratory cultures during the study. The broad goals of the observational study are to describe the risk factors and outcomes associated with early acquisition of Pa. 306 patients were randomized in the clinical trial and 1,787 were enrolled in the cohort study. Conclusions These companion studies will provide valuable epidemiological and microbiological information on early CF lung disease and Pa acquisition, and safety and clinical efficacy data on anti-pseudomonal treatment strategies for early Pa infections in the airways of young children with CF. PMID:19470318

  9. Direct Sum Decomposition of Groups

    ERIC Educational Resources Information Center

    Thaheem, A. B.

    2005-01-01

    Direct sum decomposition of Abelian groups appears in almost all textbooks on algebra for undergraduate students. This concept plays an important role in group theory. One simple example of this decomposition is obtained by using the kernel and range of a projection map on an Abelian group. The aim in this pedagogical note is to establish a direct…

  10. Decomposition of Relational Schemata into Components

    E-print Network

    Hegner, Stephen J.

    Decomposition of Relational Schemata into Components Defined by Both Projection and Restriction Version) ABSTRACT A generalized approach to the decomposition of relational schemata is developed in which horizontal and vertical decompositions. The realization of restrictions is enabled through the use

  11. Steadily propagating slip pulses driven by thermal decomposition

    NASA Astrophysics Data System (ADS)

    Platt, John D.; Viesca, Robert C.; Garagash, Dmitry I.

    2015-09-01

    Geophysical observations suggest that mature faults weaken significantly at seismic slip rates. Thermal pressurization and thermal decomposition are two mechanisms commonly used to explain this dynamic weakening. Both rely on pore fluid pressurization with thermal pressurization achieving this through thermal expansion of native solids and pore fluid and thermal decomposition by releasing additional pore fluid during a reaction. Several recent papers have looked at the role thermal pressurization plays during a dynamically propagating earthquake, but no previous models have studied the role of thermal decomposition. In this paper we present the first solutions accounting for thermal decomposition during dynamic rupture, solving for steady state self-healing slip pulses propagating at a constant rupture velocity. First, we show that thermal decomposition leads to longer slip durations, larger total slips, and a distinctive along-fault slip rate profile. Next, we show that accounting for more than one weakening mechanism allows multiple steady slip pulses to exist at a given background stress, with some solutions corresponding to different balances between thermal pressurization and thermal decomposition, and others corresponding to activating a single reaction multiple times. Finally, we study how the rupture properties depend on the fault properties and show that the impact of thermal decomposition is largely controlled by the ratio of the hydraulic and thermal diffusivities ? = ?hy/?th and the ratio of pore pressure generated to temperature rise buffered by the reaction Pr/Er.

  12. Effects observed in the ionospheric F region in the east Asian sector during the intense geomagnetic disturbances in the early part of November 2004

    NASA Astrophysics Data System (ADS)

    Sahai, Y.; Becker-Guedes, F.; Fagundes, P. R.; de Jesus, R.; de Abreu, A. J.; Otsuka, Y.; Shiokawa, K.; Igarashi, K.; Yumoto, K.; Huang, C.-S.; Lan, H. T.; Saito, A.; Guarnieri, F. L.; Pillat, V. G.; Bittencourt, J. A.

    2009-03-01

    The Sun was very active in the early part of November 2004. During the period of 8-10 November 2004, intense geomagnetic disturbances with two superstorms were observed. In a companion paper (hereinafter referred to as paper 1), the effects observed in the F region during the intense geomagnetic disturbances in the early part of November 2004 in the Latin American sector were presented. In the present paper, we investigate the effects observed in the F region during the intense geomagnetic disturbances in the early part of November 2004 in the east Asian sector. We have used the ionospheric sounding observations at Ho Chi Minh City (Vietnam) and Okinawa, Yamagawa, Kokubunji, and Wakkanai (Japan) in the present investigations. Also, GPS observations in the east Asian sector (several longitude zones) have been used to study the effect in the F region during the intense geomagnetic disturbances. The ion density versus latitudinal variations obtained by the DMSP F15 satellite orbiting at about 800 km altitude in the east Asian sector and the magnetic field data obtained at several stations in the Japanese meridian are also presented. Several important features from these observations in both the sectors during this extended period of intense geomagnetic disturbances are presented. The east Asian sector showed very pronounced effects during the second superstorm, which was preceded by two storm enhancements. It should be mentioned that around the beginning of the night on 10 November, ionospheric irregularities propagating from higher midlatitude region to low-latitude region were observed in the Japanese sector. The most intense geomagnetic field H component in that sector was observed on 10 November at L = 2.8, indicating that the auroral oval and the heating got further to low latitudes and the ionospheric irregularities observed in the Japanese sector on this night are midlatitude ionospheric disturbances associated with the second superstorm. The absence of ionospheric irregularities in the Japanese sector during the 8 November superstorm suggests that the magnetosphere-ionosphere system was possibly preconditioned (primed) when the second interplanetary structure impacted the magnetosphere.

  13. Art of spin decomposition

    E-print Network

    Xiang-Song Chen; Wei-Min Sun; Fan Wang; T. Goldman

    2011-05-31

    We analyze the problem of spin decomposition for an interacting system from a natural perspective of constructing angular momentum eigenstates. We split, from the total angular momentum operator, a proper part which can be separately conserved for a stationary state. This part commutes with the total Hamiltonian and thus specifies the quantum angular momentum. We first show how this can be done in a gauge-dependent way, by seeking a specific gauge in which part of the total angular momentum operator vanishes identically. We then construct a gauge-invariant operator with the desired property. Our analysis clarifies what is the most pertinent choice among the various proposals for decomposing the nucleon spin. A similar analysis is performed for extracting a proper part from the total Hamiltonian to construct energy eigenstates.

  14. Art of spin decomposition

    SciTech Connect

    Chen Xiangsong; Sun Weimin; Wang Fan; Goldman, T.

    2011-04-01

    We analyze the problem of spin decomposition for an interacting system from a natural perspective of constructing angular-momentum eigenstates. We split, from the total angular-momentum operator, a proper part which can be separately conserved for a stationary state. This part commutes with the total Hamiltonian and thus specifies the quantum angular momentum. We first show how this can be done in a gauge-dependent way, by seeking a specific gauge in which part of the total angular-momentum operator vanishes identically. We then construct a gauge-invariant operator with the desired property. Our analysis clarifies what is the most pertinent choice among the various proposals for decomposing the nucleon spin. A similar analysis is performed for extracting a proper part from the total Hamiltonian to construct energy eigenstates.

  15. Loss of diversity in wood-inhabiting fungal communities affects decomposition activity in Norway spruce wood

    PubMed Central

    Valentín, Lara; Rajala, Tiina; Peltoniemi, Mikko; Heinonsalo, Jussi; Pennanen, Taina; Mäkipää, Raisa

    2014-01-01

    Hundreds of wood-inhabiting fungal species are now threatened, principally due to a lack of dead wood in intensively managed forests, but the consequences of reduced fungal diversity on ecosystem functioning are not known. Several experiments have shown that primary productivity is negatively affected by a loss of species, but the effects of microbial diversity on decomposition are less studied. We studied the relationship between fungal diversity and the in vitro decomposition rate of slightly, moderately and heavily decayed Picea abies wood with indigenous fungal communities that were diluted to examine the influence of diversity. Respiration rate, wood-degrading hydrolytic enzymes and fungal community structure were assessed during a 16-week incubation. The number of observed OTUs in DGGE was used as a measure of fungal diversity. Respiration rate increased between early- and late-decay stages. Reduced fungal diversity was associated with lower respiration rates during intermediate stages of decay, but no effects were detected at later stages. The activity of hydrolytic enzymes varied among decay stages and fungal dilutions. Our results suggest that functioning of highly diverse communities of the late-decay stage were more resistant to the loss of diversity than less diverse communities of early decomposers. This indicates the accumulation of functional redundancy during the succession of the fungal community in decomposing substrates. PMID:24904544

  16. Ensemble Empirical Mode Decomposition Analysis of EEG Data Collected during a Contour Integration Task.

    PubMed

    Al-Subari, Karema; Al-Baddai, Saad; Tomé, Ana Maria; Volberg, Gregor; Hammwöhner, Rainer; Lang, Elmar W

    2015-01-01

    We discuss a data-driven analysis of EEG data recorded during a combined EEG/fMRI study of visual processing during a contour integration task. The analysis is based on an ensemble empirical mode decomposition (EEMD) and discusses characteristic features of event related modes (ERMs) resulting from the decomposition. We identify clear differences in certain ERMs in response to contour vs noncontour Gabor stimuli mainly for response amplitudes peaking around 100 [ms] (called P100) and 200 [ms] (called N200) after stimulus onset, respectively. We observe early P100 and N200 responses at electrodes located in the occipital area of the brain, while late P100 and N200 responses appear at electrodes located in frontal brain areas. Signals at electrodes in central brain areas show bimodal early/late response signatures in certain ERMs. Head topographies clearly localize statistically significant response differences to both stimulus conditions. Our findings provide an independent proof of recent models which suggest that contour integration depends on distributed network activity within the brain. PMID:25910061

  17. Ensemble Empirical Mode Decomposition Analysis of EEG Data Collected during a Contour Integration Task

    PubMed Central

    Al-Subari, Karema; Al-Baddai, Saad; Tomé, Ana Maria; Volberg, Gregor; Hammwöhner, Rainer; Lang, Elmar W.

    2015-01-01

    We discuss a data-driven analysis of EEG data recorded during a combined EEG/fMRI study of visual processing during a contour integration task. The analysis is based on an ensemble empirical mode decomposition (EEMD) and discusses characteristic features of event related modes (ERMs) resulting from the decomposition. We identify clear differences in certain ERMs in response to contour vs noncontour Gabor stimuli mainly for response amplitudes peaking around 100 [ms] (called P100) and 200 [ms] (called N200) after stimulus onset, respectively. We observe early P100 and N200 responses at electrodes located in the occipital area of the brain, while late P100 and N200 responses appear at electrodes located in frontal brain areas. Signals at electrodes in central brain areas show bimodal early/late response signatures in certain ERMs. Head topographies clearly localize statistically significant response differences to both stimulus conditions. Our findings provide an independent proof of recent models which suggest that contour integration depends on distributed network activity within the brain. PMID:25910061

  18. Hydroxyl radical formation during peroxynitrous acid decomposition

    SciTech Connect

    Coddington, J.W.; Hurst, J.K.; Lymar, S.V.

    1999-03-24

    Yields of O{sub 2} formed during decomposition of peroxynitrous acid (ONOOH) under widely varying medium conditions are compared to predictions based upon the assumption that the reaction involves formation of discrete {sm{underscore}bullet}OH and {sm{underscore}bullet}NO{sub 2} radicals as oxidizing intermediates. The kinetic model used includes all reactions of {sm{underscore}bullet}OH, {sm{underscore}bullet}O{sub 2}{sup {minus}}, and reactive nitrogen species known to be important under the prevailing conditions; because the rate constants for all of these reactions have been independently measured, the calculations contain no adjustable fitting parameters. The model quantitatively accounts for (1) the complex pH dependence of the O{sub 2} yields and (2) the unusual effects of NO{sub 2} {sup {minus}}, which inhibits O{sub 2} formation in neutral, but not alkaline, solutions and also reverses inhibition by organic {sm{underscore}bullet}OH scavengers in alkaline media. Other observations, including quenching of O{sub 2} yields by ferrocyanide and bicarbonate, the pressure dependence of the decomposition rate, and the reported dynamic behavior for O{sub 2} generation in the presence of H{sub 2}O{sub 2}, also appear to be in accord with the suggested mechanism. Overall, the close correspondence between observed and calculated O{sub 2} yields provides strong support for decomposition via homolysis of the ONOOH peroxo bond.

  19. A collection of sub-daily pressure and temperature observations for the early instrumental period with a focus on the "year without a summer" 1816

    NASA Astrophysics Data System (ADS)

    Brugnara, Y.; Auchmann, R.; Brönnimann, S.; Allan, R. J.; Auer, I.; Barriendos, M.; Bergström, H.; Bhend, J.; Brázdil, R.; Compo, G. P.; Cornes, R. C.; Dominguez-Castro, F.; van Engelen, A. F. V.; Filipiak, J.; Holopainen, J.; Jourdain, S.; Kunz, M.; Luterbacher, J.; Maugeri, M.; Mercalli, L.; Moberg, A.; Mock, C. J.; Pichard, G.; ?ezní?ková, L.; van der Schrier, G.; Slonosky, V.; Ustrnul, Z.; Valente, M. A.; Wypych, A.; Yin, X.

    2015-08-01

    The eruption of Mount Tambora (Indonesia) in April 1815 is the largest documented volcanic eruption in history. It is associated with a large global cooling during the following year, felt particularly in parts of Europe and North America, where the year 1816 became known as the "year without a summer". This paper describes an effort made to collect surface meteorological observations from the early instrumental period, with a focus on the years of and immediately following the eruption (1815-1817). Although the collection aimed in particular at pressure observations, correspondent temperature observations were also recovered. Some of the series had already been described in the literature, but a large part of the data, recently digitised from original weather diaries and contemporary magazines and newspapers, is presented here for the first time. The collection puts together more than 50 sub-daily series from land observatories in Europe and North America and from ships in the tropics. The pressure observations have been corrected for temperature and gravity and reduced to mean sea level. Moreover, an additional statistical correction was applied to take into account common error sources in mercury barometers. To assess the reliability of the corrected data set, the variance in the pressure observations is compared with modern climatologies, and single observations are used for synoptic analyses of three case studies in Europe. All raw observations will be made available to the scientific community in the International Surface Pressure Databank.

  20. Lateral biases for holding infants: early opinions, observations, and explanations, with some possible lessons for theory and research today.

    PubMed

    Harris, Lauren Julius

    2002-01-01

    In 1962, the psychologist Lee Salk reported finding that 80% of mothers held their infants on the left side of their body, so that the infant's head was to their left. Salk's finding has been amply confirmed, with new studies of mothers as well as other adults reporting figures for left-side holding ranging from 60 to 85% (e.g., de Chateau, 1983; Harris & Fitzgerald, 1985; Harris, Almerigi, & Kirsch, 2000). New studies also suggest that the bias is only for holding infants (or infant dolls), not for books, packages, or other objects (e.g., Almerigi, Carbary, & Harris, 2001; Rheingold & Keene, 1965). The possibility that it is unique to infants (or their likenesses) is what gives it special interest for investigators who study laterality of function. The discovery of the bias is often credited to Salk, but it would be more accurate to say that he rediscovered it because it was first noted at least two hundred years earlier, then, evidently, forgotten, only to be rediscovered and again forgotten several times through the early decades of the twentieth century. Over this period, however, not all agreed that the preferred side was the left: a nearly equal number said it was the right. Each group also proposed explanations for why one or the other side was preferred. They also foresaw different consequences for the infant being held. In the 1980s, I briefly described some of the early reports in essays on the history of theories and research on laterality of function (Harris, 1980, 1983). A manuscript now in preparation provides a more comprehensive description and evaluation of these reports and suggests certain lessons they may hold for current theory and research. The poster proposed for TENNET XII will summarize the main points of this new review and analysis. The poster will be organized into 6 sections, with bulleted text accompanied by drawings, photographs, and other illustrations. The plan is to make the story as visual as possible. PMID:12030474

  1. Long-term litter decomposition controlled by manganese redox cycling.

    PubMed

    Keiluweit, Marco; Nico, Peter; Harmon, Mark E; Mao, Jingdong; Pett-Ridge, Jennifer; Kleber, Markus

    2015-09-22

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn(2+) provided by fresh plant litter to produce oxidative Mn(3+) species at sites of active decay, with Mn eventually accumulating as insoluble Mn(3+/4+) oxides. Formation of reactive Mn(3+) species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn(3+)-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn(3+) species in the litter layer. This observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant-soil system may have a profound impact on litter decomposition rates. PMID:26372954

  2. Nonequilibrium adiabatic molecular dynamics simulations of methane clathrate hydrate decomposition.

    PubMed

    Alavi, Saman; Ripmeester, J A

    2010-04-14

    Nonequilibrium, constant energy, constant volume (NVE) molecular dynamics simulations are used to study the decomposition of methane clathrate hydrate in contact with water. Under adiabatic conditions, the rate of methane clathrate decomposition is affected by heat and mass transfer arising from the breakup of the clathrate hydrate framework and release of the methane gas at the solid-liquid interface and diffusion of methane through water. We observe that temperature gradients are established between the clathrate and solution phases as a result of the endothermic clathrate decomposition process and this factor must be considered when modeling the decomposition process. Additionally we observe that clathrate decomposition does not occur gradually with breakup of individual cages, but rather in a concerted fashion with rows of structure I cages parallel to the interface decomposing simultaneously. Due to the concerted breakup of layers of the hydrate, large amounts of methane gas are released near the surface which can form bubbles that will greatly affect the rate of mass transfer near the surface of the clathrate phase. The effects of these phenomena on the rate of methane hydrate decomposition are determined and implications on hydrate dissociation in natural methane hydrate reservoirs are discussed. PMID:20406006

  3. Decomposition in northern Minnesota peatlands

    SciTech Connect

    Farrish, K.W.

    1985-01-01

    Decomposition in peatlands was investigated in northern Minnesota. Four sites, an ombrotrophic raised bog, an ombrotrophic perched bog and two groundwater minerotrophic fens, were studied. Decomposition rates of peat and paper were estimated using mass-loss techniques. Environmental and substrate factors that were most likely to be responsible for limiting decomposition were monitored. Laboratory incubation experiments complemented the field work. Mass-loss over one year in one of the bogs, ranged from 11 percent in the upper 10 cm of hummocks to 1 percent at 60 to 100 cm depth in hollows. Regression analysis of the data for that bog predicted no mass-loss below 87 cm. Decomposition estimates on an area basis were 2720 and 6460 km/ha yr for the two bogs; 17,000 and 5900 kg/ha yr for the two fens. Environmental factors found to limit decomposition in these peatlands were reducing/anaerobic conditions below the water table and cool peat temperatures. Substrate factors found to limit decomposition were low pH, high content of resistant organics such as lignin, and shortages of available N and K. Greater groundwater influence was found to favor decomposition through raising the pH and perhaps by introducing limited amounts of dissolved oxygen.

  4. Stratospheric aerosol change in the early stage of volcanic disturbance by the Pinatubo eruption observed over Tsukuba, Japan

    SciTech Connect

    Hayashida, Sachiko; Sasano, Yasuhiro

    1993-04-09

    An increase in the amount of stratospheric aerosol due to the Pinatubo eruption (June 12-15, 1991, 15.14[degree]N, 120.35[degree]E) was observed from the end of June by a lidar in NIES, Tsukuba (36[degree]N, 140[degree]E). The first arrival of volcanic aerosol layers was observed just above the tropopause on June 28, 1991, only two weeks after the eruption. Aerosol layers higher than 20 km appeared sporadically in July and August, reflecting the inhomogeneity of aerosol distribution. After the change in the wind system from summer easterlies to winter westerlies, the main body of the volcanic aerosol layer made its appearance over Tsukuba. The integrated backscattering coefficient (IBC) increased in winter as a result of transportation of aerosols from the tropical region. The IBC, which can be converted to optical thickness, exceeded the level of the value observed after the El Chichon eruption. 15 refs., 4 figs.

  5. Structural optimization by multilevel decomposition

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, J.; James, B.; Dovi, A.

    1983-01-01

    A method is described for decomposing an optimization problem into a set of subproblems and a coordination problem which preserves coupling between the subproblems. The method is introduced as a special case of multilevel, multidisciplinary system optimization and its algorithm is fully described for two level optimization for structures assembled of finite elements of arbitrary type. Numerical results are given for an example of a framework to show that the decomposition method converges and yields results comparable to those obtained without decomposition. It is pointed out that optimization by decomposition should reduce the design time by allowing groups of engineers, using different computers to work concurrently on the same large problem.

  6. Perfluoropolyalkylether decomposition on catalytic aluminas

    NASA Technical Reports Server (NTRS)

    Morales, Wilfredo

    1994-01-01

    The decomposition of Fomblin Z25, a commercial perfluoropolyalkylether liquid lubricant, was studied using the Penn State Micro-oxidation Test, and a thermal gravimetric/differential scanning calorimetry unit. The micro-oxidation test was conducted using 440C stainless steel and pure iron metal catalyst specimens, whereas the thermal gravimetric/differential scanning calorimetry tests were conducted using catalytic alumina pellets. Analysis of the thermal data, high pressure liquid chromatography data, and x-ray photoelectron spectroscopy data support evidence that there are two different decomposition mechanisms for Fomblin Z25, and that reductive sites on the catalytic surfaces are responsible for the decomposition of Fomblin Z25.

  7. Descent theory for semiorthogonal decompositions

    SciTech Connect

    Elagin, Alexei D

    2012-05-31

    We put forward a method for constructing semiorthogonal decompositions of the derived category of G-equivariant sheaves on a variety X under the assumption that the derived category of sheaves on X admits a semiorthogonal decomposition with components preserved by the action of the group G on X. This method is used to obtain semiorthogonal decompositions of equivariant derived categories for projective bundles and blow-ups with a smooth centre as well as for varieties with a full exceptional collection preserved by the group action. Our main technical tool is descent theory for derived categories. Bibliography: 12 titles.

  8. Initiation and Early Evolution of the Coronal Mass Ejection on 2009 May 13 from Extreme-ultraviolet and White-light Observations

    NASA Astrophysics Data System (ADS)

    Reva, A. A.; Ulyanov, A. S.; Bogachev, S. A.; Kuzin, S. V.

    2014-10-01

    We present the results of the observations of a coronal mass ejection (CME) that occurred on 2009 May 13. The most important feature of these observations is that the CME was observed from the very early stage (the solar surface) up to a distance of 15 solar radii (R ?). Below 2 R ?, we used the data from the TESIS extreme-ultraviolet telescopes obtained in the Fe 171 Å and He 304 Å lines, and above 2 R ?, we used the observations of the LASCO C2 and C3 coronagraphs. The CME was formed at a distance of 0.2-0.5R ? from the Sun's surface as a U-shaped structure, which was observed both in the 171 Å images and in the white light. Observations in the He 304 Å line showed that the CME was associated with an erupting prominence, which was not located above—as the standard model predicts—but rather in the lowest part of the U-shaped structure close to the magnetic X point. The prominence location can be explained with the CME breakout model. Estimates showed that CME mass increased with time. The CME trajectory was curved—its heliolatitude decreased with time. The CME started at a latitude of 50° and reached the ecliptic plane at distances of 2.5 R ?. The CME kinematics can be divided into three phases: initial acceleration, main acceleration, and propagation with constant velocity. After the CME, onset GOES registered a sub-A-class flare.

  9. Atmosphere-Ice-Ocean Interactions During Early Autumn Freeze-up: Boundary-Layer and Surface Observations from the ACSE Field Program

    NASA Astrophysics Data System (ADS)

    Persson, Ola; Brooks, Barbara; Tjernström, Michael; Sedlar, Joseph; Brooks, Ian; Shupe, Matthew; Björck, Göran; Prytherch, John; Salisbury, Dominic; Achtert, Peggy; Sotiropoulou, Georgia; Johnston, Paul; Wolfe, Daniel

    2015-04-01

    Surface energy fluxes are key to the annual summer melt and autumn freeze-up of Arctic sea ice, but are strongly modulated by atmospheric, ocean, and sea-ice processes. This paper will examine direct observations of energy fluxes during the onset of autumn freeze-up from the Arctic Clouds in Summer Experiment (ACSE), and place them in context of those from other observational campaigns. The ACSE field program obtained measurements of surface energy fluxes, boundary-layer structure, cloud macro- and microphysical structure, and upper-ocean thermal and salinity structure from pack-ice and open-water regions in the eastern Arctic from early July to early October 2014. Late August and September measurements showed periods of energy flux deficits, leading to freeze-up of sea ice and the ocean surface. The surface albedo and processes impacting the energy content of the upper ocean appear key to producing a temporal difference between the freeze-up of the sea ice and adjacent open water. While synoptic conditions, atmospheric advection, and the annual solar cycle have primary influence determining when energy fluxes are conducive for melt or freeze, mesoscale atmospheric phenomena unique to the ice edge region appear to also play a role. For instance, low-level jets were often observed near the ice edge during the latter part of ACSE, and may have enhanced the turbulent energy loss. In conjunction with observations of summer melt, these observations of the onset of freeze-up suggest scenarios of key atmospheric processes, including thermal advection on various scales, that are important for the annual evolution of melt and freeze-up.

  10. From Dogmatic Discussions to Observations and Planned Experiments: Some Examples from Early Aurora Borealis Research in Finland.

    ERIC Educational Resources Information Center

    Holmberg, Peter

    1996-01-01

    Traces the evolution of physics research methods in Finland from passive observations to planned experiments. Presents examples of planned experiments designed to solve particular problems with the goal of establishing a theory of the phenomenon under study. Contains 16 references. (JRH)

  11. Initiation and early evolution of a Coronal Mass Ejection on May 13, 2009 from EUV and white-light observations

    NASA Astrophysics Data System (ADS)

    Reva, Anton; Kuzin, Sergey; Bogachev, Sergey; Ulyanov, Artyom

    In this talk we present results of the observations of a CME, which occurred on May 13, 2009. The most important feature of these observations is that the CME was observed from the very beginning stage (the solar surface) up to the distance of 15 solar radii (R_?). Below 2 R_? we used the data from the TESIS EUV telescopes obtained in the Fe 171 Å and He 304 Å lines, and above 2 R_? we used the observations of the LASCO C2 and C3 coronagraphs. Using data of these three instruments, we have studied the evolution of the CME in details. The CME had a curved trajectory -- its helio-latitude decreased with time. The mass ejection originated at a latitudes of about 50(°) and reached the ecliptic plane at a distance of 2.5 R_? from the Sun’s center. The CME velocity and acceleration increased as the CME went away from the Sun. At the distance of 15 R_? from the Sun’s center the CME had a velocity of 250 km/s and an acceleration of 5 m/s(2) . The CME was not associated with a flare, and didn’t have an impulsive acceleration phase. The mass ejection had U-shaped structure which was observed both in the 171 Å images and in white-light. The CME was formed at a distance of about 0.2 -- 0.5 R_? from the Sun’s surface. Observations in the line 304 Å showed that the CME was associated with the erupting prominence, which was located in the lowest part of the U-shaped structure close to the X-point of the magnetic reconnection. The prominence disappeared at the height of 0.4 R_? above the solar limb. Some aspects of these observations can’t be explained in the standard CME model, which predicts that the prominence should be located inside the U-shaped structure, and the CME should be associated with a flare and have an impulsive acceleration phase.

  12. Decomposition rates and termite assemblage composition in semiarid Africa

    USGS Publications Warehouse

    Schuurman, G.

    2005-01-01

    Outside of the humid tropics, abiotic factors are generally considered the dominant regulators of decomposition, and biotic influences are frequently not considered in predicting decomposition rates. In this study, I examined the effect of termite assemblage composition and abundance on decomposition of wood litter of an indigenous species (Croton megalobotrys) in five terrestrial habitats of the highly seasonal semiarid Okavango Delta region of northern Botswana, to determine whether natural variation in decomposer community composition and abundance influences decomposition rates. 1 conducted the study in two areas, Xudum and Santawani, with the Xudum study preceding the Santawani study. I assessed termite assemblage composition and abundance using a grid of survey baits (rolls of toilet paper) placed on the soil surface and checked 2-4 times/month. I placed a billet (a section of wood litter) next to each survey bait and measured decomposition in a plot by averaging the mass loss of its billets. Decomposition rates varied up to sixfold among plots within the same habitat and locality, despite the fact that these plots experienced the same climate. In addition, billets decomposed significantly faster during the cooler and drier Santawani study, contradicting climate-based predictions. Because termite incidence was generally higher in Santawani plots, termite abundance initially seemed a likely determinant of decomposition in this system. However, no significant effect of termite incidence on billet mass loss rates was observed among the Xudum plots, where decomposition rates remained low even though termite incidence varied considerably. Considering the incidences of fungus-growing termites and non-fungus-growing termites separately resolves this apparent contradiction: in both Santawani and Xudum, only fungus-growing termites play a significant role in decomposition. This result is mirrored in an analysis of the full data set of combined Xudum and Santawani data. The determination that natural variation in the abundance of a single taxonomic group of soil fauna, a termite subfamily, determines almost all observed variation in decomposition rates supports the emerging view that biotic influences may be important in many biomes and that consideration of decomposer community composition and abundance may be critical for accurate prediction of decomposition rates. ?? 2005 by the Ecological Society of America.

  13. Evaluating litter decomposition and soil organic matter dynamics in earth system models: contrasting analysis of long-term litter decomposition and steady-state soil carbon

    NASA Astrophysics Data System (ADS)

    Bonan, G. B.; Wieder, W. R.

    2012-12-01

    Decomposition is a large term in the global carbon budget, but models of the earth system that simulate carbon cycle-climate feedbacks are largely untested with respect to litter decomposition. Here, we demonstrate a protocol to document model performance with respect to both long-term (10 year) litter decomposition and steady-state soil carbon stocks. First, we test the soil organic matter parameterization of the Community Land Model version 4 (CLM4), the terrestrial component of the Community Earth System Model, with data from the Long-term Intersite Decomposition Experiment Team (LIDET). The LIDET dataset is a 10-year study of litter decomposition at multiple sites across North America and Central America. We show results for 10-year litter decomposition simulations compared with LIDET for 9 litter types and 20 sites in tundra, grassland, and boreal, conifer, deciduous, and tropical forest biomes. We show additional simulations with DAYCENT, a version of the CENTURY model, to ask how well an established ecosystem model matches the observations. The results reveal large discrepancy between the laboratory microcosm studies used to parameterize the CLM4 litter decomposition and the LIDET field study. Simulated carbon loss is more rapid than the observations across all sites, despite using the LIDET-provided climatic decomposition index to constrain temperature and moisture effects on decomposition. Nitrogen immobilization is similarly biased high. Closer agreement with the observations requires much lower decomposition rates, obtained with the assumption that nitrogen severely limits decomposition. DAYCENT better replicates the observations, for both carbon mass remaining and nitrogen, without requirement for nitrogen limitation of decomposition. Second, we compare global observationally-based datasets of soil carbon with simulated steady-state soil carbon stocks for both models. The models simulations were forced with observationally-based estimates of annual litterfall and model-derived climatic decomposition index. While comparison with the LIDET 10-year litterbag study reveals sharp contrasts between CLM4 and DAYCENT, simulations of steady-state soil carbon show less difference between models. Both CLM4 and DAYCENT significantly underestimate soil carbon. Sensitivity analyses highlight causes of the low soil carbon bias. The terrestrial biogeochemistry of earth system models must be critically tested with observations, and the consequences of particular model choices must be documented. Long-term litter decomposition experiments such as LIDET provide a real-world process-oriented benchmark to evaluate models and can critically inform model development. Analysis of steady-state soil carbon estimates reveal additional, but here different, inferences about model performance.

  14. Lignocellulose decomposition by microbial secretions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon storage in terrestrial ecosystems is contingent upon the natural resistance of plant cell wall polymers to rapid biological degradation. Nevertheless, certain microorganisms have evolved remarkable means to overcome this natural resistance. Lignocellulose decomposition by microorganisms com...

  15. Bridge Decomposition of Restriction Measures

    E-print Network

    Tom Alberts; Hugo Duminil-Copin

    2010-07-03

    Motivated by Kesten's bridge decomposition for two-dimensional self-avoiding walks in the upper half plane, we show that the conjectured scaling limit of the half-plane SAW, the SLE(8/3) process, also has an appropriately defined bridge decomposition. This continuum decomposition turns out to entirely be a consequence of the restriction property of SLE(8/3), and as a result can be generalized to the wider class of restriction measures. Specifically we show that the restriction hulls with index less than one can be decomposed into a Poisson Point Process of irreducible bridges in a way that is similar to Ito's excursion decomposition of a Brownian motion according to its zeros.

  16. Outlier Detection With Streaming Dyadic Decomposition

    E-print Network

    Grossman, Robert

    Outlier Detection With Streaming Dyadic Decomposition Chetan Gupta1,2 and Robert Grossman1,3 1- liers on streaming data in Rn . The basic idea is to compute a dyadic decomposition into cubes in Rn. Dyadic decomposition obtained under streaming setting is understood as streaming dyadic decomposition

  17. Early Radio and X-Ray Observations of the Youngest Nearby Type Ia Supernova PTF 11kly (SN 2011fe)

    NASA Technical Reports Server (NTRS)

    Horesh, Assaf; Kulkarni, S. R.; Fox, Derek B.; Carpenter, John; Kasliwal, Mansi M.; Ofek, Eran O.; Quimby, Robert; Gal-Yam, Avishay; Cenko, S. Bradley; deBruyn, A. G.; Kamble, Atish; Wijers, Ralph A. M. J.; vanderHorst, Alexander J.; Kouveliotou, Chryssa; Podsiadlowski, Philipp; Sullivan, Mark; Maguire, Kate; Howell, D. Andrew; Nugent, Peter E.; Gehrels, Neil; Law, Nicolas M.; Poznanski, Dovi; Shara, Michael

    2012-01-01

    On August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion time. We present our analysis of the radio and X-ray observations, yielding the tightest constraints yet placed on the pre-explosion mass-loss rate from the progenitor system of this supernova. We find a robust limit of M(raised dot) less than or equal to 10(exp -8) (w /100 kilometers per second ) solar mass yr(exp -1) from sensitive X-ray non-detections, as well as a similar limit from radio data, which depends, however, on assumptions about microphysical parameters. We discuss our results in the context of single-degenerate models for SNe Ia and find that our observations modestly disfavor symbiotic progenitor models involving a red giant donor, but cannot constrain systems accreting from main sequence or sub-giant stars, including the popular supersoft channel. In view of the proximity of PTF11kly and the sensitivity of our prompt observations we would have to wait for a long time (decade or longer) in order to more meaningfully probe the circumstellar matter of Ia supernovae.

  18. Optimization by nonhierarchical asynchronous decomposition

    NASA Technical Reports Server (NTRS)

    Shankar, Jayashree; Ribbens, Calvin J.; Haftka, Raphael T.; Watson, Layne T.

    1992-01-01

    Large scale optimization problems are tractable only if they are somehow decomposed. Hierarchical decompositions are inappropriate for some types of problems and do not parallelize well. Sobieszczanski-Sobieski has proposed a nonhierarchical decomposition strategy for nonlinear constrained optimization that is naturally parallel. Despite some successes on engineering problems, the algorithm as originally proposed fails on simple two dimensional quadratic programs. The algorithm is carefully analyzed for quadratic programs, and a number of modifications are suggested to improve its robustness.

  19. Sector decomposition via computational geometry

    E-print Network

    Toshiaki Kaneko; Takahiro Ueda

    2010-04-30

    A non-iterative method is presented for the factorization step of sector decomposition method, which separates infrared divergent part from loop integration. This method is based on a classification of asymptotic behavior of polynomials. The problem is converted to ones for convex body in Euclidean space. They are solved with algorithms developed in computational geometry. A test implementation shows that this method produces less number of decomposed sectors than usual iterative sector decompositions.

  20. Actual-Waste Tests of Enhanced Chemical Cleaning for Retrieval of SRS HLW Sludge Tank Heels and Decomposition of Oxalic Acid - 12256

    SciTech Connect

    Martino, Christopher J.; King, William D.; Ketusky, Edward T.

    2012-07-01

    Savannah River National Laboratory conducted a series of tests on the Enhanced Chemical Cleaning (ECC) process using actual Savannah River Site waste material from Tanks 5F and 12H. Testing involved sludge dissolution with 2 wt% oxalic acid, the decomposition of the oxalates by ozonolysis (with and without the aid of ultraviolet light), the evaporation of water from the product, and tracking the concentrations of key components throughout the process. During ECC actual waste testing, the process was successful in decomposing oxalate to below the target levels without causing substantial physical or chemical changes in the product sludge. During ECC actual waste testing, the introduction of ozone was successful in decomposing oxalate to below the target levels. This testing did not identify physical or chemical changes in the ECC product sludge that would impact downstream processing. The results from these tests confirm observations made by AREVA NP during larger scale testing with waste simulants. This testing, however, had a decreased utilization of ozone, requiring approximately 5 moles of ozone per mole of oxalate decomposed. Decomposition of oxalates in sludge dissolved in 2 wt% OA to levels near 100 ppm oxalate using ECC process conditions required 8 to 12.5 hours without the aid of UV light and 4.5 to 8 hours with the aid of UV light. The pH and ORP were tracked during decomposition testing. Sludge components were tracked during OA decomposition, showing that most components have the highest soluble levels in the initial dissolved sludge and early decomposition samples and exhibit lower soluble levels as OA decomposition progresses. The Deposition Tank storage conditions that included pH adjustment to approximately 1 M free hydroxide tended to bring the soluble concentrations in the ECC product to nearly the same level for each test regardless of storage time, storage temperature, and contact with other tank sludge material. (authors)

  1. A review of myrmecophily in ant nest beetles (Coleoptera: Carabidae: Paussinae): linking early observations with recent findings

    NASA Astrophysics Data System (ADS)

    Geiselhardt, Stefanie F.; Peschke, Klaus; Nagel, Peter

    2007-11-01

    Myrmecophily provides various examples of how social structures can be overcome to exploit vast and well-protected resources. Ant nest beetles (Paussinae) are particularly well suited for ecological and evolutionary considerations in the context of association with ants because life habits within the subfamily range from free-living and predatory in basal taxa to obligatory myrmecophily in derived Paussini. Adult Paussini are accepted in the ant society, although parasitising the colony by preying on ant brood. Host species mainly belong to the ant families Myrmicinae and Formicinae, but at least several paussine genera are not host-specific. Morphological adaptations, such as special glands and associated tufts of hair (trichomes), characterise Paussini as typical myrmecophiles and lead to two different strategical types of body shape: while certain Paussini rely on the protective type with less exposed extremities, other genera access ant colonies using glandular secretions and trichomes (symphile type). We compare these adaptations with other taxonomic groups of insects by joining contemporary research and early sources and discuss the possibility of an attracting or appeasing effect of the secretion. Species that are ignored by their host ants might use chemical mimicry instead. Furthermore, vibrational signals may contribute to ant-beetle communication, and chemical signals have proven to play a role in host finding. The powerful defense chemistry of paussines as “bombardier beetles” is not used in contact with host ants. We attempt to trace the evolution of myrmecophily in paussines by reviewing important aspects of the association between paussine beetles and ants, i.e. morphological and potential chemical adaptations, life cycle, host specificity, alimentation, parasitism and sound production.

  2. The Size Evolution of Passive Galaxies: Observations From the Wide-Field Camera 3 Early Release Science Program

    NASA Technical Reports Server (NTRS)

    Ryan, R. E., Jr.; Mccarthy, P.J.; Cohen, S. H.; Yan, H.; Hathi, N. P.; Koekemoer, A. M.; Rutkowski, M. J.; Mechtley, M. R.; Windhorst, R. A.; O’Connell, R. W.; Balick, B.; Bond, H. E.; Bushouse, H.; Calzetti, D.; Crockett, R. M.; Disney, M.; Dopita, M. A.; Frogel, J. A.; Hall, D., N., B.; Holtzman, J. A.; Kaviraj, S.; Kimble, R. A.; MacKenty, J.; Trauger, J.; Young, E.

    2012-01-01

    We present the size evolution of passively evolving galaxies at z approximately 2 identified in Wide-Field Camera 3 imaging from the Early Release Science program. Our sample was constructed using an analog to the passive BzK galaxy selection criterion, which isolates galaxies with little or no ongoing star formation at z greater than approximately 1.5. We identify 30 galaxies in approximately 40 arcmin(sup 2) to H less than 25 mag. By fitting the 10-band Hubble Space Telescope photometry from 0.22 micrometers less than approximately lambda (sub obs) 1.6 micrometers with stellar population synthesis models, we simultaneously determine photometric redshift, stellar mass, and a bevy of other population parameters. Based on the six galaxies with published spectroscopic redshifts, we estimate a typical redshift uncertainty of approximately 0.033(1+z).We determine effective radii from Sersic profile fits to the H-band image using an empirical point-spread function. By supplementing our data with published samples, we propose a mass-dependent size evolution model for passively evolving galaxies, where the most massive galaxies (M(sub *) approximately 10(sup 11) solar mass) undergo the strongest evolution from z approximately 2 to the present. Parameterizing the size evolution as (1 + z)(sup - alpha), we find a tentative scaling of alpha approximately equals (-0.6 plus or minus 0.7) + (0.9 plus or minus 0.4) log(M(sub *)/10(sup 9 solar mass), where the relatively large uncertainties reflect the poor sampling in stellar mass due to the low numbers of highredshift systems. We discuss the implications of this result for the redshift evolution of the M(sub *)-R(sub e) relation for red galaxies.

  3. The autoimmunity-associated BLK haplotype exhibits cis-regulatory effects on mRNA and protein expression that are prominently observed in B cells early in development.

    PubMed

    Simpfendorfer, Kim R; Olsson, Lina M; Manjarrez Orduño, Nataly; Khalili, Houman; Simeone, Alyssa M; Katz, Matthew S; Lee, Annette T; Diamond, Betty; Gregersen, Peter K

    2012-09-01

    The gene B lymphocyte kinase (BLK) is associated with rheumatoid arthritis, systemic lupus erythematosus and several other autoimmune disorders. The disease risk haplotype is known to be associated with reduced expression of BLK mRNA transcript in human B cell lines; however, little is known about cis-regulation of BLK message or protein levels in native cell types. Here, we show that in primary human B lymphocytes, cis-regulatory effects of disease-associated single nucleotide polymorphisms in BLK are restricted to naïve and transitional B cells. Cis-regulatory effects are not observed in adult B cells in later stages of differentiation. Allelic expression bias was also identified in primary human T cells from adult peripheral and umbilical cord blood (UCB), thymus and tonsil, although mRNA levels were reduced compared with B cells. Allelic regulation of Blk expression at the protein level was confirmed in UCB B cell subsets by intracellular staining and flow cytometry. Blk protein expression in CD4(+) and CD8(+) T cells was documented by western blot analysis; however, differences in protein expression levels by BLK genotype were not observed in any T cell subset. Blk allele expression differences at the protein level are thus restricted to early B cells, indicating that the involvement of Blk in the risk for autoimmune disease likely acts during the very early stages of B cell development. PMID:22678060

  4. Investigating early-type galaxy evolution with a multiwavelength approach - I. X-ray properties of 12 galaxies observed with Swift and XMM-Newton

    NASA Astrophysics Data System (ADS)

    Trinchieri, G.; Rampazzo, R.; Mazzei, P.; Marino, A.; Wolter, A.

    2015-05-01

    We report here the results from the X-ray observations of 12 early-type galaxies (ETGs) observed with Swift and XMM-Newton, originally selected from a sample of galaxies with Spitzer and/or GALEX data. With the combined analysis of new X-ray and optical-UV observations and of previously available data from archives, we aim at investigating the relation between X-ray luminosity and evolutionary phases of ETGs. We will interpret the results with the additional aid of smoothed particle hydrodynamics chemo-photometric simulations. All galaxies have been detected in the X-ray band, with luminosities Lx > 1039 erg s-1. X-ray emitting gas has been detected in about half of the sample, with luminosities from ?1039 to 1040 erg s-1. UVOT images show a variety of morphologies, from absence of peculiar features relative to optical wavelengths typical of red and dead early-types, to well defined almost circular rings clearly emerging in the U band, to more spectacular and complex features connected to recent or even ongoing star formation (SF). We find little evidence of any influence of the SF activity on their global X-ray properties, and in particular, on the luminosity-weighted age of the system, usually estimated in the nuclear region. However, with the present data we cannot exclude that such a relation exists on smaller scales, related to the specific sites where we see evidence of newly formed stars, such as outer rings and arcs and peculiar features observed in UV images.

  5. Early-type stars observed in the ESO UVES Paranal Observatory Project - V. Time-variable interstellar absorption

    NASA Astrophysics Data System (ADS)

    McEvoy, Catherine M.; Smoker, Jonathan V.; Dufton, Philip L.; Smith, Keith T.; Kennedy, Michael B.; Keenan, Francis P.; Lambert, David L.; Welty, Daniel E.; Lauroesch, James T.

    2015-08-01

    The structure and properties of the diffuse interstellar medium (ISM) on small scales, sub-au to 1 pc, are poorly understood. We compare interstellar absorption lines, observed towards a selection of O- and B-type stars at two or more epochs, to search for variations over time caused by the transverse motion of each star combined with changes in the structure in the foreground ISM. Two sets of data were used: 83 VLT/UVES spectra with approximately 6 yr between epochs and 21 McDonald observatory 2.7-m telescope echelle spectra with 6-20 yr between epochs, over a range of scales from ˜0-360 au. The interstellar absorption lines observed at the two epochs were subtracted and searched for any residuals due to changes in the foreground ISM. Of the 104 sightlines investigated with typically five or more components in Na I D, possible temporal variation was identified in five UVES spectra (six components), in Ca II, Ca I and/or Na I absorption lines. The variations detected range from 7 per cent to a factor of 3.6 in column density. No variation was found in any other interstellar species. Most sightlines show no variation, with 3? upper limits to changes of the order 0.1-0.3 dex in Ca II and Na I. These variations observed imply that fine-scale structure is present in the ISM, but at the resolution available in this study, is not very common at visible wavelengths. A determination of the electron densities and lower limits to the total number density of a sample of the sightlines implies that there is no striking difference between these parameters in sightlines with, and sightlines without, varying components.

  6. EARLY- AND LATE-TIME OBSERVATIONS OF SN 2008ha: ADDITIONAL CONSTRAINTS FOR THE PROGENITOR AND EXPLOSION

    SciTech Connect

    Foley, Ryan J.; Challis, Peter J.; Kirshner, Robert P.; Brown, Peter J.; Rest, Armin; Wood-Vasey, W. Michael

    2010-01-01

    We present a new maximum-light optical spectrum of the extremely low luminosity and exceptionally low-energy Type Ia supernova (SN Ia) 2008ha, obtained one week before the earliest published spectrum. Previous observations of SN 2008ha were unable to distinguish between a massive star and white dwarf (WD) origin for the SN. The new maximum-light spectrum, obtained one week before the earliest previously published spectrum, unambiguously shows features corresponding to intermediate mass elements, including silicon, sulfur, and carbon. Although strong silicon features are seen in some core-collapse SNe, sulfur features, which are a signature of carbon/oxygen burning, have always been observed to be weak in such events. It is therefore likely that SN 2008ha was the result of a thermonuclear explosion of a carbon-oxygen WD. Carbon features at maximum light show that unburned material is present to significant depths in the SN ejecta, strengthening the case that SN 2008ha was a failed deflagration. We also present late-time imaging and spectroscopy that are consistent with this scenario.

  7. Observational Evidence Against Mountain-Wave Generation of Ice Nuclei as a Prerequisite for the Formation of Three Solid Nitric Acid Polar Stratospheric Clouds Observed in the Arctic in Early December 1999

    NASA Technical Reports Server (NTRS)

    Pagan, Kathy L.; Tabazadeh, Azadeh; Drdla, Katja; Hervig, Mark E.; Eckermann, Stephen D.; Browell, Edward V.; Legg, Marion J.; Foschi, Patricia G.

    2004-01-01

    A number of recently published papers suggest that mountain-wave activity in the stratosphere, producing ice particles when temperatures drop below the ice frost point, may be the primary source of large NAT particles. In this paper we use measurements from the Advanced Very High Resolution Radiometer (AVHRR) instruments on board the National Oceanic and Atmospheric Administration (NOAA) polar-orbiting satellites to map out regions of ice clouds produced by stratospheric mountain-wave activity inside the Arctic vortex. Lidar observations from three DC-8 flights in early December 1999 show the presence of solid nitric acid (Type Ia or NAT) polar stratospheric clouds (PSCs). By using back trajectories and superimposing the position maps on the AVHRR cloud imagery products, we show that these observed NAT clouds could not have originated at locations of high-amplitude mountain-wave activity. We also show that mountain-wave PSC climatology data and Mountain Wave Forecast Model 2.0 (MWFM-2) raw hemispheric ray and grid box averaged hemispheric wave temperature amplitude hindcast data from the same time period are in agreement with the AVHRR data. Our results show that ice cloud formation in mountain waves cannot explain how at least three large scale NAT clouds were formed in the stratosphere in early December 1999.

  8. X-Ray, UV, and Optical Observations of Supernova 2006bp with Swift: Detection of Early X-Ray Emission

    NASA Technical Reports Server (NTRS)

    Immler, S.; Brown, P. J.; Milne, P.; Dessart, L.; Mazzali, P. A.; Landsman, W.; Gehrels, N.; Petre, R.; Burrows, D. N.; Nousek, J. A.; Chevalier, R. A.; Williams, C. L.; Koss, M.; Stockdale, C. J.; Kelley, M. T.; Weiler, K. W.; Holland, S. T.; Pian, E.; Roming, P. W. A.; Pooley, D.; Nomoto, K.; Greiner, J.; Campana, S.; Soderberg, A. M.

    2007-01-01

    We present results on the X-ray and optical/UV emission from the Type IIP supernova (SN) 2006bp and the interaction of the SW shock with its environment, obtained with the X-Ray Telescope (XRT) and UV/Optical Telescope (UVOT) on-board the Swift observatory. SN 2006bp is detected in X-rays at a 4.5 sigmalevel of significance in the merged XRT data from days 1 to 12 after the explosion. If the (0.2-10 keV band) X-ray luminosity of L(sub 0.2-10) = (1.8 plus or minus 0.4) x l0(exp 39 ergs s(exp -1) is caused by interaction of the SN shock with circumstellar material (CSM), deposited by a stellar wind from the progenitor's companion star, a mass-loss rate of M is approximately 2x10(exp -6) solar mass yr(exp -1) (v(sub w)/10 km s(exp -l) is inferred. The mass-loss rate is one of the lowest ever recorded for a core-collapse SN and consistent with the non-detection in the radio with the VLA on days 2, 9, and 11 after the explosion. The Swift data further show a fading of the X-ray emission starting around day 12 after the explosion. In combination with a follow-up XMM-Newton observation obtained on day 21 after the explosion, an X-ray rate of decline Lx, varies as t(exp -n) with index n = 1.2 plus or minus 0.6 is inferred. Since no other SN has been detected in X-rays prior to the optical peak and since Type IIP SNe have an extended 'plateau' phase in the optical, we discuss the scenario that the X-rays might be due to inverse Compton scattering of photospheric optical photons off relativistic electrons produced in circumstellar shocks. However, due to the high required value of the Lorentz factor (approximately 10-100), inconsistent with the ejecta velocity inferred from optical line widths, we conclude that Inverse Compton scattering is an unlikely explanation for the observed X-ray emission. The fast evolution of the optical/ultraviolet (1900-5500A) spectral energy distribution and the spectral changes observed with Swift reveal the onset of metal line-blanketing and cooling of the expanding photosphere during the first few weeks after the outburst.

  9. Solving Polynomial Systems via Triangular Decomposition (Spine title: Solving Polynomial Systems via Triangular Decomposition)

    E-print Network

    Moreno Maza, Marc

    Solving Polynomial Systems via Triangular Decomposition (Spine title: Solving Polynomial Systems via Triangular Decomposition) (Thesis format: Monograph) by Changbo Chen Graduate Program in Computer Polynomial Systems via Triangular Decomposition is accepted in partial fulfillment of the requirements

  10. Mechanism of the Thermal Decomposition of Furan

    NASA Astrophysics Data System (ADS)

    Vasiliou, Angayle; Ellison, G. Barney; Nimlos, Mark R.; Daily, John W.

    2009-06-01

    Both furan (C_4H_4O) and furfural (C_4H_3O-CHO) areimportant products in biomass pyrolysis. We have used a resistively-heated SiC tubular reactor with a 30 microseconds residence time to study the thermal cracking of furan. The decomposition products are identified by two independent techniques: 118.2 nm VUV photoionization mass spectroscopy and infrared spectroscopy. We observe three different thermal dissociation channels leading to: a) CH_3CCH + CO b) HCCH + CH_2CO c) HCCCH_2.

  11. A characterization of the two-step reaction mechanism of phenol decomposition by a Fenton reaction

    NASA Astrophysics Data System (ADS)

    Valdés, Cristian; Alzate-Morales, Jans; Osorio, Edison; Villaseñor, Jorge; Navarro-Retamal, Carlos

    2015-11-01

    Phenol is one of the worst contaminants at date, and its degradation has been a crucial task over years. Here, the decomposition process of phenol, in a Fenton reaction, is described. Using scavengers, it was observed that decomposition of phenol was mainly influenced by production of hydroxyl radicals. Experimental and theoretical activation energies (Ea) for phenol oxidation intermediates were calculated. According to these Ea, phenol decomposition is a two-step reaction mechanism mediated predominantly by hydroxyl radicals, producing a decomposition yield order given as hydroquinone > catechol > resorcinol. Furthermore, traces of reaction derived acids were detected by HPLC and GS-MS.

  12. Near Infrared Observations of a Redshift 5.34 Galaxy: Further Evidence for Dust Absorption in the Early Universe

    E-print Network

    L. Armus; K. Matthews; G. Neugebauer; B. T. Soifer

    1998-06-17

    Imaging at 1.25 and 2.20 microns has been obtained of the field containing the galaxy (RD1) found at redshift 5.34 by Dey et al.(1998). This galaxy has been detected at 1.25 microns, while the lower redshift (z=4.02) galaxy also found in the same field by Dey et al. was detected at both 1.25 and 2.20 microns. Comparison to stellar population synthesis models indicates that if RD1 is a young ( 0.5 mag) is indicated. Combined with observations of other high redshift systems, these data show that dust is likely to be an important component of young galaxies even at redshifts of z > 5. The extinction-corrected monochromatic luminosity of RD1 at 1500 angstroms is then a factor of about three larger than L(1500)* as determined by Dickinson (1998) for z ~ 3 starburst galaxies. The implied star formation rate in RD1, corrected for extinction, is ~ 50-100 solar masses per year.

  13. Initiation and early evolution of the coronal mass ejection on 2009 May 13 from extreme-ultraviolet and white-light observations

    SciTech Connect

    Reva, A. A.; Ulyanov, A. S.; Bogachev, S. A.; Kuzin, S. V.

    2014-10-01

    We present the results of the observations of a coronal mass ejection (CME) that occurred on 2009 May 13. The most important feature of these observations is that the CME was observed from the very early stage (the solar surface) up to a distance of 15 solar radii (R {sub ?}). Below 2 R {sub ?}, we used the data from the TESIS extreme-ultraviolet telescopes obtained in the Fe 171 Å and He 304 Å lines, and above 2 R {sub ?}, we used the observations of the LASCO C2 and C3 coronagraphs. The CME was formed at a distance of 0.2-0.5R {sub ?} from the Sun's surface as a U-shaped structure, which was observed both in the 171 Å images and in the white light. Observations in the He 304 Å line showed that the CME was associated with an erupting prominence, which was not located above—as the standard model predicts—but rather in the lowest part of the U-shaped structure close to the magnetic X point. The prominence location can be explained with the CME breakout model. Estimates showed that CME mass increased with time. The CME trajectory was curved—its heliolatitude decreased with time. The CME started at a latitude of 50° and reached the ecliptic plane at distances of 2.5 R {sub ?}. The CME kinematics can be divided into three phases: initial acceleration, main acceleration, and propagation with constant velocity. After the CME, onset GOES registered a sub-A-class flare.

  14. THE RESOLVED STELLAR POPULATION IN 50 REGIONS OF M83 FROM HST/WFC3 EARLY RELEASE SCIENCE OBSERVATIONS

    SciTech Connect

    Kim, Hwihyun; Cohen, Seth H.; Windhorst, Rogier A.; Whitmore, Bradley C.; Mutchler, Max; Bond, Howard E.; Chandar, Rupali; Saha, Abhijit; Kaleida, Catherine C.; Calzetti, Daniela; O'Connell, Robert W.; Balick, Bruce; Carollo, Marcella; Disney, Michael J.; Dopita, Michael A.; Frogel, Jay A.; Hall, Donald N. B.; Holtzman, Jon A.; Kimble, Randy A.; McCarthy, Patrick J.; and others

    2012-07-01

    We present a multi-wavelength photometric study of {approx}15,000 resolved stars in the nearby spiral galaxy M83 (NGC 5236, D = 4.61 Mpc) based on Hubble Space Telescope Wide Field Camera 3 observations using four filters: F336W, F438W, F555W, and F814W. We select 50 regions (an average size of 260 pc by 280 pc) in the spiral arm and inter-arm areas of M83 and determine the age distribution of the luminous stellar populations in each region. This is accomplished by correcting for extinction toward each individual star by comparing its colors with predictions from stellar isochrones. We compare the resulting luminosity-weighted mean ages of the luminous stars in the 50 regions with those determined from several independent methods, including the number ratio of red-to-blue supergiants, morphological appearance of the regions, surface brightness fluctuations, and the ages of clusters in the regions. We find reasonably good agreement between these methods. We also find that young stars are much more likely to be found in concentrated aggregates along spiral arms, while older stars are more dispersed. These results are consistent with the scenario that star formation is associated with the spiral arms, and stars form primarily in star clusters and then disperse on short timescales to form the field population. The locations of Wolf-Rayet stars are found to correlate with the positions of many of the youngest regions, providing additional support for our ability to accurately estimate ages. We address the effects of spatial resolution on the measured colors, magnitudes, and age estimates. While individual stars can occasionally show measurable differences in the colors and magnitudes, the age estimates for entire regions are only slightly affected.

  15. The Resolved Stellar Population in 50 Regions of M83 from HST/WFC3 Early Release Science Observations

    NASA Technical Reports Server (NTRS)

    Kim, Hwihyun; Whitmore, Bradley C.; Chandar, Rupali; Saha, Abhijit; Kaleida, Catherine C.; Mutchler, Max; Cohen, Seth H.; Calzetti, Daniela; O’Connell, Robert W.; Windhorst, Rogier A.; Balick, Bruce; Bond, Howard E.; Carollo, Marcella; Disney, Michael J.; Dopita, Michael A.; Frogel, Jay A.; Hall, Donald N. B.; Holtzman, Jon A.; Kimble, Randy A.; McCarthy, Patrick J.; Paresce, Francesco; Silk, Joe I; Trauger, John T.; Walker, Alistair R.; Young, Erick T.

    2012-01-01

    We present a multi-wavelength photometric study of approximately 15,000 resolved stars in the nearby spiral galaxy M83 (NGC 5236, D = 4.61 Mpc) based on Hubble Space Telescope Wide Field Camera 3 observations using four filters: F336W, F438W, F555W, and F814W. We select 50 regions (an average size of 260 pc by 280 pc) in the spiral arm and inter-arm areas of M83 and determine the age distribution of the luminous stellar populations in each region. This is accomplished by correcting for extinction toward each individual star by comparing its colors with predictions from stellar isochrones.We compare the resulting luminosity-weighted mean ages of the luminous stars in the 50 regions with those determined from several independent methods, including the number ratio of red-to-blue supergiants, morphological appearance of the regions, surface brightness fluctuations, and the ages of clusters in the regions. We find reasonably good agreement between these methods. We also find that young stars are much more likely to be found in concentrated aggregates along spiral arms, while older stars are more dispersed. These results are consistent with the scenario that star formation is associated with the spiral arms, and stars form primarily in star clusters and then disperse on short timescales to form the field population. The locations ofWolf-Rayet stars are found to correlate with the positions of many of the youngest regions, providing additional support for our ability to accurately estimate ages. We address the effects of spatial resolution on the measured colors, magnitudes, and age estimates. While individual stars can occasionally show measurable differences in the colors and magnitudes, the age estimates for entire regions are only slightly affected.

  16. ALMA Early Science Observations of Outbursting Stellar Systems:Disk Masses for FU Ori and EXor Objects

    NASA Astrophysics Data System (ADS)

    Cieza, Lucas A.; Prieto, Jose Luis; Zhu, Zhaohuan; Tobin, John J.; Williams, Jonathan P.; Hales, Antonio; Casassus, Simon; Principe, David; Schreiber, Matthias R.

    2016-01-01

    It is believed that low-mass stars build a significant fraction of their total mass during short outbursts of enhanced accretion (up to 10E-4 MSOLAR /yr). The most dramatic episodic accretion events known in Young Stellar Objects (YSOs) are FU Ori and EXor outbursts. FU Ori objects are characterized by a sudden brightening of 5 magnitudes or more within one year and remain bright for decades. EXor objects have lower amplitude outbursts on shorter timescales (months to years). Here we present an ALMA 230 GHz (1.3 mm / band-6) mini-survey of 8 outbursting sources (three FU Ori and ve EXor objects) in Orion with 1" (450 AU) resolution. We present continuum, 12CO, 13CO, and C18O line images and derive dust and (when possible) gas disk masses. The disk masses derived from the line observations are systematically lower (by factors of 3-5) than those calculated from the continuum and adopting the standard gas-to-dust ratio of 100, which agrees with results on T Tauri disks in Taurus. After beam deconvolution, we nd that the disks are remarkably compact (r = 70-150 AU). The 1.3 mm fuxes of the outbursting sources span over three orders of magnitude, but the FU Ori objects are signi cantly brighter than the EXor objects. The inferred disk masses for the brightest objects are > 0.1 Msolar , rendering gravitational instability a likely outburst mechanism. On the other hand, the inferred disk masses for the faintest targets are ~ 1-5 MJUP , and thus an alternative mechanism must be responsible for their outbursts.

  17. Constraining Galaxy Evolution With Bulge-Disk-Bar Decomposition

    E-print Network

    Tim Weinzirl; Shardha Jogee; Fabio D. Barazza

    2008-02-26

    Structural decomposition of galaxies into bulge, disk, and bar components is important to address a number of scientific problems. Measuring bulge, disk, and bar structural parameters will set constraints on the violent and secular processes of galaxy assembly and recurrent bar formation and dissolution models. It can also help to quantify the fraction and properties of bulgeless galaxies (those systems having no bulge or only a relatively insignificant disky-pseudobulges), which defy galaxy formation paradigms requiring almost every disk galaxy to have a classical bulge at its core. We demonstrate a proof of concept and show early results of our ongoing three-component bulge-disk-bar decomposition of NIR images for a sample of three complementary samples spanning different epochs and different environments (field and cluster). In contrast to most early studies, which only attempt two-component bulge-disk decomposition, we fit three components using GALFIT: a bulge, a disk, and a bar. We show that it is important to include the bar component, as this can significantly lower the bulge-to-total luminosity ratio (B/T), in many cases by a factor of two or more, thus effectively changing the Hubble type of a galaxy from early to late.

  18. Gauge-invariant decomposition of nucleon spin

    SciTech Connect

    Wakamatsu, M.

    2010-06-01

    We investigate the relation between the known decompositions of the nucleon spin into its constituents, thereby clarifying in what respect they are common and in what respect they are different essentially. The decomposition recently proposed by Chen et al. can be thought of as a nontrivial generalization of the gauge-variant Jaffe-Manohar decomposition so as to meet the gauge-invariance requirement of each term of the decomposition. We however point out that there is another gauge-invariant decomposition of the nucleon spin, which is closer to the Ji decomposition, while allowing the decomposition of the gluon total angular momentum into the spin and orbital parts. After clarifying the reason why the gauge-invariant decomposition of the nucleon spin is not unique, we discuss which decomposition is more preferable from an experimental viewpoint.

  19. Trade-Offs in Resource Allocation Among Moss Species Control Decomposition in Boreal Peatlands

    SciTech Connect

    Turetsky, M. R.; Crow, S. E.; Evans, R. J.; Vitt, D. H.; Wieder, R. K.

    2008-01-01

    We separated the effects of plant species controls on decomposition rates from environmental controls in northern peatlands using a full factorial, reciprocal transplant experiment of eight dominant bryophytes in four distinct peatland types in boreal Alberta, Canada. Standard fractionation techniques as well as compound-specific pyrolysis molecular beam mass spectrometry were used to identify a biochemical mechanism underlying any interspecific differences in decomposition rates. We found that over a 3-year field incubation, individual moss species and not micro-environmental conditions controlled early stages of decomposition. Across species, Sphagnum mosses exhibited a trade-off in resource partitioning into metabolic and structural carbohydrates, a pattern that served as a strong predictor of litter decomposition. Decomposition rates showed a negative co-variation between species and their microtopographic position, as species that live in hummocks decomposed slowly but hummock microhabitats themselves corresponded to rapid decomposition rates. By forming litter that degrades slowly, hummock mosses appear to promote the maintenance of macropore structure in surface peat hummocks that aid in water retention. Many northern regions are experiencing rapid climate warming that is expected to accelerate the decomposition of large soil carbon pools stored within peatlands. However, our results suggest that some common peatland moss species form tissue that resists decomposition across a range of peatland environments, suggesting that moss resource allocation could stabilize peatland carbon losses under a changing climate.

  20. Rank-based decompositions of morphological templates.

    PubMed

    Sussner, P; Ritter, G X

    2000-01-01

    Methods for matrix decomposition have found numerous applications in image processing, in particular for the problem of template decomposition. Since existing matrix decomposition techniques are mainly concerned with the linear domain, we consider it timely to investigate matrix decomposition techniques in the nonlinear domain with applications in image processing. The mathematical basis for these investigations is the new theory of rank within minimax algebra. Thus far, only minimax decompositions of rank 1 and rank 2 matrices into outer product expansions are known to the image processing community. We derive a heuristic algorithm for the decomposition of matrices having arbitrary rank. PMID:18262978

  1. Decomposition of Artinian Alternative Rings

    NASA Astrophysics Data System (ADS)

    Vidiger, A.

    1982-02-01

    In this paper a number of theorems are obtained on decompositions of Artinian alternative rings, generalizing analogous theorems of Szász, Šne?dmjuller, Kertész et al. for associative Artinian rings. For example, it is shown that every alternative Artinian ring decomposes into a direct sum of torsion parts and a torsion free ideal. With several additional restrictions, we obtain a decomposition of any alternative Artinian ring into a direct sum of an ideal and a left ideal, allowing a rather detailed description. A description of hereditarily Artinian alternative rings is given.Bibliography: 16 titles.

  2. Decomposition pathways in age hardening of Ti-Al-N films

    NASA Astrophysics Data System (ADS)

    Rachbauer, R.; Massl, S.; Stergar, E.; Holec, D.; Kiener, D.; Keckes, J.; Patscheider, J.; Stiefel, M.; Leitner, H.; Mayrhofer, P. H.

    2011-07-01

    The ability to increase the thermal stability of protective coatings under work load gives rise to scientific and industrial interest in age hardening of complex nitride coating systems such as ceramic-like Ti1-xAlxN. However, the decomposition pathway of these systems from single-phase cubic to the thermodynamically stable binary nitrides (cubic TiN and wurtzite AlN), which are essential for age hardening, are not yet fully understood. In particular, the role of decomposition kinetics still requires more detailed investigation. In the present work, the combined effect of annealing time and temperature upon the nano-structural development of Ti0.46Al0.54N thin films is studied, with a thermal exposure of either 1 min or 120 min in 100 °C steps from 500 °C to 1400 °C. The impact of chemical changes at the atomic scale on the development of micro-strain and mechanical properties is studied by post-annealing investigations using X-ray diffraction, nanoindentation, 3D-atom probe tomography and high-resolution transmission electron microscopy. The results clearly demonstrate that the spinodal decomposition process, triggering the increase of micro-strain and hardness, although taking place throughout the entire volume, is enhanced at high diffusivity paths such as grain or column boundaries and followed within the grains. Ab initio calculations further show that the early stages of wurtzite AlN precipitation are connected with increased strain formation, which is in excellent agreement with experimental observations.

  3. IN SITU INFRARED STUDY OF CATALYTIC DECOMPOSITION OF NO

    SciTech Connect

    KHALID ALMUSAITEER; RAM KRISHNAMURTHY; STEVEN S.C. CHUANG

    1998-08-18

    The growing concerns for the environment and increasingly stringent standards for NO emission have presented a major challenge to control NO emissions from electric utility plants and automobiles. Catalytic decomposition of NO is the most attractive approach for the control of NO emission for its simplicity. Successful development of an effective catalyst for NO decomposition will greatly decrease the equipment and operation cost of NO control. Due to lack of understanding of the mechanism of NO decomposition, efforts on the search of an effective catalyst have been unsuccessful. Scientific development of an effective catalyst requires fundamental understanding of the nature of active site, the rate-limiting step, and an approach to prolong the life of the catalyst. Research is proposed to study the reactivity of adsorbates for the direct NO decomposition and to investigate the feasibility of two novel approaches for improving catalyst activity and resistance to sintering. The first approach is the use of silanation to stabilize metal crystallites and supports for Cu-ZSM-5 and promoted Pt catalysts; the second is utilization of oxygen spillover and desorption to enhance NO decomposition activity. An innovative infrared reactor system will be used to observe and determine the dynamic behavior and the reactivity of adsorbates during NO decomposition, oxygen spillover, and silanation. A series of experiments including X-ray diffraction, temperature programmed desorption, temperature programmed reaction, X-ray photoelectron spectroscopy will be used to characterized the catalysts. The information obtained from this study will provide a scientific basis for developing an effective catalyst for the NO decomposition under practical flue gas conditions.

  4. In Situ Infrared Study of Catalytic Decomposition of NO

    SciTech Connect

    Cher-Dip Tan; Steven S.C. Chuang

    1997-07-17

    The growing concerns for the environment and increasingly stringent standards for NO emission have presented a major challenge to control NO emmissions from electric utility plants and automobiles. Catalytic decomposition of NO is the most attractive approach for the control of NO emission for its simplicity. Successful development of an effective catalyst for NO decomposition will greatly decrease the equipment and operation cost of NO control. Due to lack of understanding of the mechanism of NO decomposition, efforts on the search of an effective catalyst have been unsuccesful. Scientific development of an effective catalyst requires fundamental understanding of the nature of active site, the rate-limiting step, and an approach to prolong the life of the catalyst. Research is proposed to study the reactivity of adsorbates for the direct NO decomposition and to investigate the feasibility of two novel approaches for improving catalyst activity and resistance to sintering. The first approach is the use of silanation to stabilize metal crystallites and supports for Cu-ZSM-5 and promoted Pt catalysts; the second is utilization of oxygen spillover and desorption to enhance NO decomposition activity. An innovative infrared reactor system will be used to observe and determine the dynamic behavior and the reactivity of adsorbates during NO decomposition, oxygen spillover, and silanation. A series of experiments including X-ray diffraction, temperature programmed desorption, temperature programmed reaction, X-ray photoelectron spectroscopy will be used to characterized the catalysts. The information obtained from this study will provide a scientific basis for developing an effective catalyst for the NO decomposition under practical flue gas conditions.

  5. Early impact of treatment with tiotropium, long-acting anticholinergic preparation, in patients with COPD – real-life experience from an observational study

    PubMed Central

    Jahnz-Ró?yk, Karina; Szepiel, Pawe?

    2015-01-01

    Background Long-acting inhaled bronchodilators, including anticholinergic tiotropium, are recommended for the maintenance therapy of chronic obstructive pulmonary disease (COPD). It has been shown in a number of studies that treatment with tiotropium alleviates symptoms, improves exercise tolerance, health status, and reduces exacerbations in patients with moderate to very severe stage COPD. Aim The aim of this noninterventional study was to observe the early effects of the maintenance treatment with tiotropium in patients with COPD of different severities, who had been previously treated on a regular basis, or as required, with at least one short-acting bronchodilator, in a real-life setting in Poland. The effect of the treatment was assessed through the collection of COPD Assessment Test (CAT) data. Patients and methods The MATHS clinical study was an observational, noninterventional, open-label, prospective, uncontrolled, single-arm, postmarketing, surveillance, real-life study conducted with the involvement of 236 pulmonology clinics based in Poland. The tiotropium observational period was 3 months. The health and COPD status was measured with the CAT questionnaire. The primary efficacy endpoint was the mean change from the baseline in the total CAT score at the end of the 3-month observational period. Results Patients treated with 18 ?g of tiotropium once daily for 3 months showed a statistically significant result, with a clinically meaningful mean reduction (improvement) of 7.0 points in the total CAT score. The improvement was slightly greater in patients with more severe COPD; the mean change in the total CAT score was 7.6 in the subgroup of patients with more severe COPD and 6.7 points in the subgroup of patients with moderate COPD. Conclusion Results of this real-life study provide further support for the use of tiotropium as a first-line maintenance treatment for patients with COPD of different severities in Poland. PMID:25834420

  6. Symmetry of Attractors and the KarhunenLo`eve Decomposition

    E-print Network

    Nicol, Matthew

    Symmetry of Attractors and the Karhunen­Lo`eve Decomposition Michael Dellnitz Department in the time­average of an appropriate observable such as the intensity of transmitted light in the Faraday] have investigated the Faraday surface wave model, looking for indications of pattern on average

  7. What drives plant litter decomposition globally? Ecological Monographs?

    E-print Network

    Tennessee, University of

    What drives plant litter decomposition globally? Ecological Monographs? Carri J. LeRoy1,2,3 , Dylan and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996 #12;Abstract - 268 Global leaf-litter) of terrestrial plant litter were reported. For each observation of k, climatic variables such as latitude

  8. DECOMPOSITION OF MULTIVARIATE DATASETS WITH STRUCTURE/ORDERING

    E-print Network

    do. For the case with observation ordering the maximum autocorrelation factor (MAF) trans- form-mode analysis of the datamatrix. We denote this methods Q-MAF decomposition. It turns out that in many situations the new variables resulting from the MAF and the Q-MAF analyses can be interpreted as a frequency

  9. Radiocesium immobilization to leaf litter by fungi during first-year decomposition in a deciduous forest in Fukushima.

    PubMed

    Huang, Yao; Kaneko, Nobuhiro; Nakamori, Taizo; Miura, Toshiko; Tanaka, Yoichiro; Nonaka, Masanori; Takenaka, Chisato

    2016-02-01

    Vast forest areas in eastern Japan have been contaminated with radio-isotopes by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Radiocesium (radioCs) is known to remain bioavailable in forest ecosystems for a long time, and it is necessary to terminate the cycling process to decontaminate the forest ecosystem. We observed radiocesium concentrations of leaf litter during decomposition on a forest floor where radiocesium ((137)Cs) contamination was ?155 kBq/m(2). Litter bag experiments were conducted with newly fallen mixed deciduous leaf litter in a deciduous forest (alt. 610 m) about 50 km from the FDNPP. Litter bags were retrieved in April, June, August, October, and December 2012. Fresh litter (137)Cs concentration was ?3000 Bq/kg in December 2011. During the decomposition process on the forest floor, litter (137)Cs concentration increased rapidly and exceeded 25,000 Bq/kg after 6 months, whereas potassium (K) concentration in the litter was rather stable, indicating that radiocesium and K showed contrasting dynamics during the early decomposition phase. Nitrogen, phosphorus, and (137)Cs contents were positively correlated to fungal biomass, evaluated by phospholipid fatty acids in the litter during decomposition. The increase of radiocesium concentration mainly occurred during from April to October, when fungal growth peaked. Therefore, this suggests fungal translocation of nutrients from outside the litter substrate (immobilization) is the mechanism to increase radiocesium in the decomposing litter. The amount of (137)Cs contained in the 1-year-old decomposed leaf litter was estimated to be 4% per area of the soil-contaminated (137)Cs. PMID:26630038

  10. Graphs States and the necessity of Euler Decomposition

    E-print Network

    Ross Duncan; Simon Perdrix

    2009-02-03

    Coecke and Duncan recently introduced a categorical formalisation of the interaction of complementary quantum observables. In this paper we use their diagrammatic language to study graph states, a computationally interesting class of quantum states. We give a graphical proof of the fixpoint property of graph states. We then introduce a new equation, for the Euler decomposition of the Hadamard gate, and demonstrate that Van den Nest's theorem--locally equivalent graphs represent the same entanglement--is equivalent to this new axiom. Finally we prove that the Euler decomposition equation is not derivable from the existing axioms.

  11. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Products 2 2012-01-01 2012-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products...Inspection; Disposition of Carcasses and Parts § 381.93 Decomposition. Carcasses of poultry deleteriously affected by...

  12. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Products 2 2014-01-01 2014-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products...Inspection; Disposition of Carcasses and Parts § 381.93 Decomposition. Carcasses of poultry deleteriously affected by...

  13. Tremolite Decomposition and Water on Venus

    NASA Technical Reports Server (NTRS)

    Johnson, N. M.; Fegley, B., Jr.

    2000-01-01

    We present experimental data showing that the decomposition rate of tremolite, a hydrous mineral, is sufficiently slow that it can survive thermal decomposition on Venus over geologic timescales at current and higher surface temperatures.

  14. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Products 2 2010-01-01 2010-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products...Inspection; Disposition of Carcasses and Parts § 381.93 Decomposition. Carcasses of poultry deleteriously affected by...

  15. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Products 2 2013-01-01 2013-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products...Inspection; Disposition of Carcasses and Parts § 381.93 Decomposition. Carcasses of poultry deleteriously affected by...

  16. A Domain Decomposition Approach for Uncertainty Analysis

    E-print Network

    Liao, Qifeng

    This paper proposes a decomposition approach for uncertainty analysis of systems governed by partial differential equations (PDEs). The system is split into local components using domain decomposition. Our domain-decomposed ...

  17. The decomposition of fine and coarse roots: their global patterns and controlling factors

    PubMed Central

    Zhang, Xinyue; Wang, Wei

    2015-01-01

    Fine root decomposition represents a large carbon (C) cost to plants, and serves as a potential soil C source, as well as a substantial proportion of net primary productivity. Coarse roots differ markedly from fine roots in morphology, nutrient concentrations, functions, and decomposition mechanisms. Still poorly understood is whether a consistent global pattern exists between the decomposition of fine (<2?mm root diameter) and coarse (?2?mm) roots. A comprehensive terrestrial root decomposition dataset, including 530 observations from 71 sampling sites, was thus used to compare global patterns of decomposition of fine and coarse roots. Fine roots decomposed significantly faster than coarse roots in middle latitude areas, but their decomposition in low latitude regions was not significantly different from that of coarse roots. Coarse root decomposition showed more dependence on climate, especially mean annual temperature (MAT), than did fine roots. Initial litter lignin content was the most important predictor of fine root decomposition, while lignin to nitrogen ratios, MAT, and mean annual precipitation were the most important predictors of coarse root decomposition. Our study emphasizes the necessity of separating fine roots and coarse roots when predicting the response of belowground C release to future climate changes. PMID:25942391

  18. The decomposition of fine and coarse roots: their global patterns and controlling factors.

    PubMed

    Zhang, Xinyue; Wang, Wei

    2015-01-01

    Fine root decomposition represents a large carbon (C) cost to plants, and serves as a potential soil C source, as well as a substantial proportion of net primary productivity. Coarse roots differ markedly from fine roots in morphology, nutrient concentrations, functions, and decomposition mechanisms. Still poorly understood is whether a consistent global pattern exists between the decomposition of fine (<2?mm root diameter) and coarse (?2?mm) roots. A comprehensive terrestrial root decomposition dataset, including 530 observations from 71 sampling sites, was thus used to compare global patterns of decomposition of fine and coarse roots. Fine roots decomposed significantly faster than coarse roots in middle latitude areas, but their decomposition in low latitude regions was not significantly different from that of coarse roots. Coarse root decomposition showed more dependence on climate, especially mean annual temperature (MAT), than did fine roots. Initial litter lignin content was the most important predictor of fine root decomposition, while lignin to nitrogen ratios, MAT, and mean annual precipitation were the most important predictors of coarse root decomposition. Our study emphasizes the necessity of separating fine roots and coarse roots when predicting the response of belowground C release to future climate changes. PMID:25942391

  19. The decomposition of fine and coarse roots: their global patterns and controlling factors

    NASA Astrophysics Data System (ADS)

    Zhang, Xinyue; Wang, Wei

    2015-05-01

    Fine root decomposition represents a large carbon (C) cost to plants, and serves as a potential soil C source, as well as a substantial proportion of net primary productivity. Coarse roots differ markedly from fine roots in morphology, nutrient concentrations, functions, and decomposition mechanisms. Still poorly understood is whether a consistent global pattern exists between the decomposition of fine (<2?mm root diameter) and coarse (?2?mm) roots. A comprehensive terrestrial root decomposition dataset, including 530 observations from 71 sampling sites, was thus used to compare global patterns of decomposition of fine and coarse roots. Fine roots decomposed significantly faster than coarse roots in middle latitude areas, but their decomposition in low latitude regions was not significantly different from that of coarse roots. Coarse root decomposition showed more dependence on climate, especially mean annual temperature (MAT), than did fine roots. Initial litter lignin content was the most important predictor of fine root decomposition, while lignin to nitrogen ratios, MAT, and mean annual precipitation were the most important predictors of coarse root decomposition. Our study emphasizes the necessity of separating fine roots and coarse roots when predicting the response of belowground C release to future climate changes.

  20. Observation of wavelength-sensitive mass-independent sulfur isotope effects during SO2 photolysis: Implications for the early atmosphere

    NASA Astrophysics Data System (ADS)

    Farquhar, James; Savarino, Joel; Airieau, Sabine; Thiemens, Mark H.

    2001-12-01

    Mass-independent isotopic signatures for ?33S, ?34S, and ?36S produced in the photolysis of sulfur dioxide exhibit a strong wavelength dependence. Photolysis experiments with three light sources (ArF excimer laser (193 nm), mercury resonance lamp (184.9 and 253.7 nm), and KrF excimer laser (248 nm) are presented. Products of sulfur dioxide photolysis undertaken with 193-nm radiation exhibit characteristics that are similar to sulfur multiple-isotope data for terrestrial sedimentary rock samples older than 2450 Ma (reported by Farquhar et al. [2000a]), while photolysis experiments undertaken with radiation at other wavelengths (longer than 220 nm and at 184.9 nm) exhibit different characteristics. The spectral window between 190 and 220 nm falls between the Schumann-Runge bands of oxygen and the Hartley bands of ozone, and its absorption is therefore more sensitive to changes in altitude and atmospheric oxygen content than neighboring wavelengths. These two observations are used to suggest a link between sulfur dioxide photolysis at 193 nm and sulfur isotope anomalies in Archean rocks. This hypothesis includes the suggestion that UV wavelengths shorter than 200 nm penetrated deep in the Earth's atmosphere during the Archean. Potential implications of this hypothesis for the chemistry, composition, and UV absorption of the atmosphere are explored. We also explore the implications of these observations for documentation of bacterial sulfur metabolisms early in Earth's history.

  1. Contrasting Effects of Substrate and Fertilizer Nitrogen on the Early

    E-print Network

    Thomas, David D.

    Contrasting Effects of Substrate and Fertilizer Nitrogen on the Early Stages of Litter of N fertil- ization on decomposition. I directly compared internal substrate N and externally supplied sites in central Minnesota. N fertilization increased decomposition at only two of eight sites, even

  2. AVALANCHES, SANDPILES AND TUTTE DECOMPOSITION

    E-print Network

    Gabrielov, Andrei

    AVALANCHES, SANDPILES AND TUTTE DECOMPOSITION Andrei GABRIELOV Department of Geology, Cornell and avalanche models of failure were introduced recently (Bak et al., 1987, and an avalanche of publications properties of an important class of these models, Abelian sandpiles (Dhar, 1990) and Abelian avalanches

  3. The ecology of carrion decomposition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carrion, or the remains of dead animals, is something that most people would like to avoid. It is visually unpleasant, emits foul odors, and may be the source of numerous pathogens. Decomposition of carrion, however, provides a unique opportunity for scientists to investigate how nutrients cycle t...

  4. Microbial interactions during carrion decomposition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This addresses the microbial ecology of carrion decomposition in the age of metagenomics. It describes what is known about the microbial communities on carrion, including a brief synopsis about the communities on other organic matter sources. It provides a description of studies using state-of-the...

  5. Reduced Decompositions Richard P. Stanley

    E-print Network

    | 2 sisi+1si = si+1sisi+1. (We don't need s2 i = 1.) Reduced Decompositions ­ p. #12;Tits' theorem a by applying sisj = sjsi, |i - j| 2 sisi+1si = si+1sisi+1. (We don't need s2 i = 1.) E.g., (2, 3, 2, 1) R

  6. 2D Spinodal Decomposition in

    E-print Network

    California at San Diego, University of

    University of California, San Diego #12;What is Spinodal Decomposition? #12;Cahn-Hilliard Equation · The order parameter: the concentration: · The Landau-Ginzburg Free Energy: · Fick's Law: · Chemical Potential: #12;Cahn-Hilliard Equation · Cahn-Hilliard Equation: · Modified Navier Stokes Equation: #12

  7. ABSTRACT DECOMPOSITION THEOREM AND APPLICATIONS

    E-print Network

    Grossberg, Rami

    . In this paper, we prove a decomposition theorem for ab- stract elementary classes K with the amalgamation models of a totally transcen- dental good diagram D. We also prove the nonstructure part necessary, many generic constructions, classes of models with amalgamation over sets (infinitary, Ln), as well

  8. ABSTRACT DECOMPOSITION THEOREM AND APPLICATIONS

    E-print Network

    Grossberg, Rami

    . In this paper, we prove a decomposition theorem for ab­ stract elementary classes K with the amalgamation models of a totally transcen­ dental good diagram D. We also prove the nonstructure part necessary model theory, many generic constructions, classes of models with amalgamation over sets (infinitary, L n

  9. Cadaver decomposition in terrestrial ecosystems

    NASA Astrophysics Data System (ADS)

    Carter, David O.; Yellowlees, David; Tibbett, Mark

    2007-01-01

    A dead mammal (i.e. cadaver) is a high quality resource (narrow carbon:nitrogen ratio, high water content) that releases an intense, localised pulse of carbon and nutrients into the soil upon decomposition. Despite the fact that as much as 5,000 kg of cadaver can be introduced to a square kilometre of terrestrial ecosystem each year, cadaver decomposition remains a neglected microsere. Here we review the processes associated with the introduction of cadaver-derived carbon and nutrients into soil from forensic and ecological settings to show that cadaver decomposition can have a greater, albeit localised, effect on belowground ecology than plant and faecal resources. Cadaveric materials are rapidly introduced to belowground floral and faunal communities, which results in the formation of a highly concentrated island of fertility, or cadaver decomposition island (CDI). CDIs are associated with increased soil microbial biomass, microbial activity (C mineralisation) and nematode abundance. Each CDI is an ephemeral natural disturbance that, in addition to releasing energy and nutrients to the wider ecosystem, acts as a hub by receiving these materials in the form of dead insects, exuvia and puparia, faecal matter (from scavengers, grazers and predators) and feathers (from avian scavengers and predators). As such, CDIs contribute to landscape heterogeneity. Furthermore, CDIs are a specialised habitat for a number of flies, beetles and pioneer vegetation, which enhances biodiversity in terrestrial ecosystems.

  10. CARS probe of RDX decomposition

    NASA Astrophysics Data System (ADS)

    Aron, Kenneth; Harris, L. E.

    1984-01-01

    Coherent anti-Stokes Raman scattering (CARS) was used to probe RDX (hexahydro-1,3,5-trinitro- s-triazine) in a carbohydrate matrix burning unconfined in air. Several spectral regions were scanned in an attempt to document the transient species of the RDX combustion for use in determining decomposition mechanisms.

  11. DECOMPOSITION USING MAXIMUM AUTOCORRELATION FACTORS

    E-print Network

    the maximum autocorrelation factor (MAF) transform was proposed for multivariate imagery in [18 with variable ordering. This corresponds to a Q-mode analysis of the data matrix. We denote this methods Q-MAF decomposition. It turns out that in many situations the new variables resulting from the MAF and the Q-MAF

  12. Crop residue decomposition in Minnesota biochar amended plots

    NASA Astrophysics Data System (ADS)

    Weyers, S. L.; Spokas, K. A.

    2014-02-01

    Impacts of biochar application at laboratory scales are routinely studied, but impacts of biochar application on decomposition of crop residues at field scales have not been widely addressed. The priming or hindrance of crop residue decomposition could have a cascading impact on soil processes, particularly those influencing nutrient availability. Our objectives were to evaluate biochar effects on field decomposition of crop residue, using plots that were amended with biochars made from different feedstocks and pyrolysis platforms prior to the start of this study. Litterbags containing wheat straw material were buried below the soil surface in a continuous-corn cropped field in plots that had received one of seven different biochar amendments or a non-charred wood pellet amendment 2.5 yr prior to start of this study. Litterbags were collected over the course of 14 weeks. Microbial biomass was assessed in treatment plots the previous fall. Though first-order decomposition rate constants were positively correlated to microbial biomass, neither parameter was statistically affected by biochar or wood-pellet treatments. The findings indicated only a residual of potentially positive and negative initial impacts of biochars on residue decomposition, which fit in line with established feedstock and pyrolysis influences. Though no significant impacts were observed with field-weathered biochars, effective soil management may yet have to account for repeat applications of biochar.

  13. Kinetic modeling of Pt-catalyzed glycolaldehyde decomposition to syngas.

    PubMed

    Salciccioli, Michael; Vlachos, Dionisios G

    2012-05-10

    Fundamental knowledge of the elementary reaction mechanisms involved in oxygenate decomposition on transition metal catalysts can facilitate the optimization of future catalyst and reactor systems for biomass upgrade to fuels and chemicals. Pt-catalyzed decomposition of glycolaldehyde, as the smallest oxygenate with alcohol and aldehyde functionality, was studied via a DFT-based microkinetic model. It was found that two decomposition pathways exist. Under conditions of low hydrogen surface coverage, the initial C-H bond breaking reaction to HOCH(2)CO* is prevalent, while under conditions of high hydrogen coverage, the rather unexpected O-H bond forming reaction to HOCH(2)CHOH* is more active (subsequent decomposition is energetically favorable from HOCH(2)CHOH*). Our results indicate the possibility that (de)hydrogenation chemistry is rate-controlling in many small polyoxygenate biomass derivatives, and suitable catalysts are needed. Finally, DFT was used to understand the increased decomposition activity observed on the surface segregated Ni-Pt-Pt bimetallic catalyst. It was found that the initial O-H bond breaking of glycolaldehyde to OCH(2)CHO* has an activation barrier of just 0.21 eV. This barrier is lower than that of any glycolaldehyde consuming reaction on Pt. These computational predictions are in qualitative agreement with experimental results. PMID:22483365

  14. Ultrasonic irradiation of carbofuran: decomposition kinetics and reactor characterization.

    PubMed

    Hua, I; Pfalzer-Thompson, U

    2001-04-01

    The sonochemical decomposition of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl,C12H15NO3) in a parallel plate near-field acoustical processor (NAP) is reported. Ultrasonic irradiation was performed at 16 and 20 kHz, under a total applied power of 1800 W. Carbofuran decomposition was enhanced with increasing power densities (1.65 W mL-1-5.55 W mL-1), and with decreasing initial concentrations (25 microM vs. 130 microM). The nature of the dissolved gas in solution also influenced the observed decomposition rate. The hydrodynamic behavior of the NAP reactor was characterized by calculating the Reynolds numbers and by performing tracer studies with a conservative tracer, sodium chloride (NaCl). The calculated dispersion coefficients indicate an intermediate amount of dispersion during operation of the reactor. PMID:11317891

  15. A two-stage clinical decision support system for early recognition and stratification of patients with sepsis: an observational cohort study

    PubMed Central

    Lyons, Jason J; Greene, Tracy L; Haley, James M

    2015-01-01

    Objective To examine the diagnostic accuracy of a two-stage clinical decision support system for early recognition and stratification of patients with sepsis. Design Observational cohort study employing a two-stage sepsis clinical decision support to recognise and stratify patients with sepsis. The stage one component was comprised of a cloud-based clinical decision support with 24/7 surveillance to detect patients at risk of sepsis. The cloud-based clinical decision support delivered notifications to the patients’ designated nurse, who then electronically contacted a provider. The second stage component comprised a sepsis screening and stratification form integrated into the patient electronic health record, essentially an evidence-based decision aid, used by providers to assess patients at bedside. Setting Urban, 284 acute bed community hospital in the USA; 16,000 hospitalisations annually. Participants Data on 2620 adult patients were collected retrospectively in 2014 after the clinical decision support was implemented. Main outcome measure ‘Suspected infection’ was the established gold standard to assess clinical decision support clinimetric performance. Results A sepsis alert activated on 417 (16%) of 2620 adult patients hospitalised. Applying ‘suspected infection’ as standard, the patient population characteristics showed 72% sensitivity and 73% positive predictive value. A postalert screening conducted by providers at bedside of 417 patients achieved 81% sensitivity and 94% positive predictive value. Providers documented against 89% patients with an alert activated by clinical decision support and completed 75% of bedside screening and stratification of patients with sepsis within one hour from notification. Conclusion A clinical decision support binary alarm system with cross-checking functionality improves early recognition and facilitates stratification of patients with sepsis. PMID:26688744

  16. The Partial Fractions Decomposition The Simplest Case

    E-print Network

    Fournier, John J.F.

    The Partial Fractions Decomposition The Simplest Case In the most common partial fraction The Partial Fractions Decomposition 1 #12;Now back to N(z) (z-a1)�···�(z-ad) Apply Lemma 1, with D(z) = (z - a Joel Feldman. 2012. All rights reserved. February 14, 2012 The Partial Fractions Decomposition 2 #12

  17. MORTENSON'S IDENTITIES AND PARTIAL FRACTION DECOMPOSITION

    E-print Network

    Prodinger, Helmut

    MORTENSON'S IDENTITIES AND PARTIAL FRACTION DECOMPOSITION HELMUT PRODINGER Abstract. We reprove two) . . . (z - n) · Y will undergo partial fraction decomposition. · The resulting equation will be multiplied) m + z j(j + m + z) . Then partial fraction decomposition results in n k=0 n k n + k k (-1)n-k m + k

  18. Investigating hydrogel dosimeter decomposition by chemical methods

    NASA Astrophysics Data System (ADS)

    Jordan, Kevin

    2015-01-01

    The chemical oxidative decomposition of leucocrystal violet micelle hydrogel dosimeters was investigated using the reaction of ferrous ions with hydrogen peroxide or sodium bicarbonate with hydrogen peroxide. The second reaction is more effective at dye decomposition in gelatin hydrogels. Additional chemical analysis is required to determine the decomposition products.

  19. TENSOR COMPLETION THROUGH MULTIPLE KRONECKER PRODUCT DECOMPOSITION

    E-print Network

    Cichocki, Andrzej

    TENSOR COMPLETION THROUGH MULTIPLE KRONECKER PRODUCT DECOMPOSITION Anh-Huy Phan1 , Andrzej Cichocki decomposition approach to impute missing val- ues in tensor data. The method uses smaller scale multiway patches available tensor completion methods. Index Terms-- tensor decomposition, tensor completion, Kronecker tensor

  20. Periodic decomposition of integer valued Gyula Karolyi

    E-print Network

    Károlyi, Gyula

    Periodic decomposition of integer valued functions Gyula K´arolyi , Tam´as Keleti , G´eza K prove that the existence of a real valued periodic decomposition of a Z Z function implies the existence of an integer valued periodic decomposition with the same periods. This result depends

  1. LU Decomposition 1.0 Introduction

    E-print Network

    McCalley, James D.

    1 LU Decomposition 1.0 Introduction We have seen how to construct the Y-bus used in the matrix that allows us to do this is called LU decomposition. It is actually a very widely known and used method in power systems. A much more common application of LU decomposition is in the numerical, iterative

  2. DECOMPOSITION OF THREE-DIMENSIONAL MAGNETOTELLURIC DATA

    E-print Network

    Jones, Alan G.

    Chapter 13 DECOMPOSITION OF THREE-DIMENSIONAL MAGNETOTELLURIC DATA Xavier Garcia and Alan G. Jones Geological Survey of Canada. 615 Booth Street. Ottawa, ON, KIA OE9, Canada Abstract: Decomposition is the most widely adopted tensor decomposition approach, and rightly so given its physical basis and its

  3. Decomposition Methods 1.0 Introduction

    E-print Network

    McCalley, James D.

    1 Decomposition Methods 1.0 Introduction Consider the XYZ corporation that has 10 departments, each are referred to as decomposition methods. #12;3 2.0 Connection with optimization: problem structure [2] Linear to decomposition methods. Almost all of these structures involve the constraint matrix A bei

  4. Decomposition Orders another generalisation of the fundamental

    E-print Network

    Luttik, Bas

    Decomposition Orders another generalisation of the fundamental theorem of arithmetic Bas Luttik a, The Netherlands Abstract We discuss unique decomposition in partial commutative monoids. Inspired by a result from process theory, we propose the notion of decomposition order for partial commutative monoids, and prove

  5. Temperature Sensitivity of Black Carbon Decomposition and

    E-print Network

    Lehmann, Johannes

    Temperature Sensitivity of Black Carbon Decomposition and Oxidation B I N H T H A N H N G U Y E N received March 23, 2010. Accepted March 31, 2010. Global warming accelerates decomposition of soil organicSOCinmanysystems,theinfluenceoftemperature on decomposition of BC bearing different chemical and physical structures remains poorly understood. Four BC

  6. Spectral decomposition of broad-line agns and host galaxies

    SciTech Connect

    Vanden Berk, Daniel E.; Shen, Jiajian; Yip, Ching-Wa; Schneider, Donald P.; Connolly, Andrew J.; Burton, Ross E.; Jester, Sebastian; Hall, Patrick B.; Szalay, Alex S.; Brinkmann, John; /Apache Point Observ.

    2005-09-01

    Using an eigenspectrum decomposition technique, we separate the host galaxy from the broad line active galactic nucleus (AGN) in a set of 4666 spectra from the Sloan Digital Sky Survey (SDSS), from redshifts near zero up to about 0.75. The decomposition technique uses separate sets of galaxy and quasar eigenspectra to efficiently and reliably separate the AGN and host spectroscopic components. The technique accurately reproduces the host galaxy spectrum, its contributing fraction, and its classification. We show how the accuracy of the decomposition depends upon S/N, host galaxy fraction, and the galaxy class. Based on the eigencoefficients, the sample of SDSS broad-line AGN host galaxies spans a wide range of spectral types, but the distribution differs significantly from inactive galaxies. In particular, post-starburst activity appears to be much more common among AGN host galaxies. The luminosities of the hosts are much higher than expected for normal early-type galaxies, and their colors become increasingly bluer than early-type galaxies with increasing host luminosity. Most of the AGNs with detected hosts are emitting at between 1% and 10% of their estimated Eddington luminosities, but the sensitivity of the technique usually does not extend to the Eddington limit. There are mild correlations among the AGN and host galaxy eigencoefficients, possibly indicating a link between recent star formation and the onset of AGN activity. The catalog of spectral reconstruction parameters is available as an electronic table.

  7. Surgical Data and Early Postoperative Outcomes after Minimally Invasive Lumbar Interbody Fusion: Results of a Prospective, Multicenter, Observational Data-Monitored Study

    PubMed Central

    Pereira, Paulo; Buzek, David; Franke, Jörg; Senker, Wolfgang; Kosmala, Arkadiusz; Hubbe, Ulrich; Manson, Neil; Rosenberg, Wout; Assietti, Roberto; Martens, Frederic; Barbanti Brodano, Giovanni; Scheufler, Kai-Michael

    2015-01-01

    Minimally invasive lumbar interbody fusion (MILIF) offers potential for reduced operative morbidity and earlier recovery compared with open procedures for patients with degenerative lumbar disorders (DLD). Firm conclusions about advantages of MILIF over open procedures cannot be made because of limited number of large studies of MILIF in a real-world setting. Clinical effectiveness of MILIF in a large, unselected real-world patient population was assessed in this Prospective, monitored, international, multicenter, observational study. Objective: To observe and document short-term recovery after minimally invasive interbody fusion for DLD. Materials and Methods: In a predefined 4-week analysis from this study, experienced surgeons (?30 MILIF surgeries pre-study) treated patients with DLD by one- or two-level MILIF. The primary study objective was to document patients’ short-term post-interventional recovery (primary objective) including back/leg pain (visual analog scale [VAS]), disability (Oswestry Disability Index [ODI]), health status (EQ-5D) and Patient satisfaction. Results: At 4 weeks, 249 of 252 patients were remaining in the study; the majority received one-level MILIF (83%) and TLIF was the preferred approach (94.8%). For one-level (and two-level) procedures, surgery duration was 128 (182) min, fluoroscopy time 115 (154) sec, and blood-loss 164 (233) mL. Time to first ambulation was 1.3 days and time to study-defined surgery recovery was 3.2 days. Patients reported significantly (P < 0.0001) reduced back pain (VAS: 2.9 vs 6.2), leg pain (VAS: 2.5 vs 5.9), and disability (ODI: 34.5% vs 45.5%), and a significantly (P < 0.0001) improved health status (EQ-5D index: 0.61 vs 0.34; EQ VAS: 65.4 vs 52.9) 4 weeks postoperatively. One adverse event was classified as related to the minimally invasive surgical approach. No deep site infections or deaths were reported. Conclusions: For experienced surgeons, MILIF for DLD demonstrated early benefits (short time to first ambulation, early recovery, high patient satisfaction and improved patient-reported outcomes) and low major perioperative morbidity at 4 weeks postoperatively. PMID:25811615

  8. UP-BEAT (Upper Limb Baby Early Action–observation Training): protocol of two parallel randomised controlled trials of action–observation training for typically developing infants and infants with asymmetric brain lesions

    PubMed Central

    Guzzetta, Andrea; Boyd, Roslyn N; Perez, Micah; Ziviani, Jenny; Burzi, Valentina; Slaughter, Virginia; Rose, Stephen; Provan, Kerry; Findlay, Lisa; Fisher, Imogen; Colombini, Francesca; Tealdi, Gessica; Marchi, Viviani; Whittingham, Koa

    2013-01-01

    Introduction Infants with asymmetric brain lesions are at high risk of developing congenital hemiplegia. Action–observation training (AOT) has been shown to effectively improve upper limb motor function in adults with chronic stroke. AOT is based on action observation, whereby new motor skills can be learnt by observing motor actions. This process is facilitated by the Mirror Neuron System, which matches observed and performed motor actions. This study aims to determine the efficacy of AOT in: (1) influencing the early development of reaching and grasping of typically developing infants and (2) improving the upper limb activity of infants with asymmetric brain lesions. Methods and analysis This study design comprises two parallel randomised sham-controlled trials (RCTs) in: (1) typically developing infants (cohort I) and (2) infants with asymmetric brain lesions (eg, arterial stroke, venous infarction, intraventricular haemorrhage or periventricular leukomalacia; cohort II). Cohort II will be identified through a neonatal ultrasound or neonatal MRI. A sham control will be used for both RCTs, taking into consideration that it would be unethical to give no intervention to an at-risk population. Based on a two-tailed t test of two independent means, with a significance (?) level of 0.05, 80% power, predicted effect size of 0.8 and a 90% retention rate, we require 20 participants in each group (total sample of 40) for cohort I. The sample size for cohort II was based on the assumption that the effect size of the proposed training would be similar to that found by Heathcock et al in preterm born infants (n=26) with a mean effect size of 2.4. Given the high effect size, the calculation returned a sample of only four participants per group, on a two-tailed t test, with a significance (?) level of 0.05 and 80% power. As cohort II will consist of two subgroups of lesion type (ie, arterial stroke and venous infarction), we have quadrupled the sample to include 16 participants in each group (total sample of 32). Infants will be randomised to receive either AOT or standard Toy Observation Training (TOT). Both interventions will be of 4?weeks’ duration, from the infant's 9th–13th post-term week of age. Three sessions of 5?min each will be performed each day for 6?days/week (total of 6?h over 28?days). Parents of the AOT group will repeatedly show the infant a grasping action on a set of three toys, presented in random order. Parents of the TOT group will show the infant the same set of three toys, in random order, without demonstrating the grasping action. At 14, 16 and 18?weeks, the quantity and quality of reaching and grasping will be measured using the Grasping and Reaching Assessment of Brisbane; symmetry of reaching and grasping will be measured using the Hand Assessment of Infants (HAI) and pressure of grasping for each hand with a customised pressure sensor. At 6?months’ corrected age, the primary outcome measures will be the HAI and Bayley Scales of Infant and Toddler Development (third edition; BSID III), to measure cognitive and motor development. At 8?months, HAI and EEG will be used to measure brain activity and cortical coherence. At 12?months, the primary outcome measures will again be HAI and BSID III. Dissemination This paper outlines the theoretical basis, study hypotheses and outcome measures for two parallel RCTs comparing the novel intervention Action–observation training with standard TOT in: (1) influencing the early development of reaching and grasping of typically developing infants and (2) improving the upper limb motor activity of infants with asymmetric brain lesions. Trial Registration ACTRN1261100991910. Web address of trial http://www.ANZCTR.org.au/ACTRN12611000991910.aspx PMID:23418301

  9. Nonlinear mode decomposition: A noise-robust, adaptive decomposition method

    NASA Astrophysics Data System (ADS)

    Iatsenko, Dmytro; McClintock, Peter V. E.; Stefanovska, Aneta

    2015-09-01

    The signals emanating from complex systems are usually composed of a mixture of different oscillations which, for a reliable analysis, should be separated from each other and from the inevitable background of noise. Here we introduce an adaptive decomposition tool—nonlinear mode decomposition (NMD)—which decomposes a given signal into a set of physically meaningful oscillations for any wave form, simultaneously removing the noise. NMD is based on the powerful combination of time-frequency analysis techniques—which, together with the adaptive choice of their parameters, make it extremely noise robust—and surrogate data tests used to identify interdependent oscillations and to distinguish deterministic from random activity. We illustrate the application of NMD to both simulated and real signals and demonstrate its qualitative and quantitative superiority over other approaches, such as (ensemble) empirical mode decomposition, Karhunen-Loève expansion, and independent component analysis. We point out that NMD is likely to be applicable and useful in many different areas of research, such as geophysics, finance, and the life sciences. The necessary matlab codes for running NMD are freely available for download.

  10. Nonlinear mode decomposition: A noise-robust, adaptive decomposition method.

    PubMed

    Iatsenko, Dmytro; McClintock, Peter V E; Stefanovska, Aneta

    2015-09-01

    The signals emanating from complex systems are usually composed of a mixture of different oscillations which, for a reliable analysis, should be separated from each other and from the inevitable background of noise. Here we introduce an adaptive decomposition tool-nonlinear mode decomposition (NMD)-which decomposes a given signal into a set of physically meaningful oscillations for any wave form, simultaneously removing the noise. NMD is based on the powerful combination of time-frequency analysis techniques-which, together with the adaptive choice of their parameters, make it extremely noise robust-and surrogate data tests used to identify interdependent oscillations and to distinguish deterministic from random activity. We illustrate the application of NMD to both simulated and real signals and demonstrate its qualitative and quantitative superiority over other approaches, such as (ensemble) empirical mode decomposition, Karhunen-Loève expansion, and independent component analysis. We point out that NMD is likely to be applicable and useful in many different areas of research, such as geophysics, finance, and the life sciences. The necessary matlab codes for running NMD are freely available for download. PMID:26465549

  11. Noisy matrix decomposition via convex relaxation: Optimal rates in high dimensions

    E-print Network

    Agarwal, Alekh

    We analyze a class of estimators based on convex relaxation for solving high-dimensional matrix decomposition problems. The observations are noisy realizations of a linear transformation [bar through "X" symbol] of the sum ...

  12. Potential role of gas hydrate decomposition in generating submarine slope failures: Chapter 12

    USGS Publications Warehouse

    Pauli, Charles K.; mUssler, William III; Dillon, William P.

    2003-01-01

    Gas hydrate decomposition is hypothesized to be a factor in generating weakness in continental margin sediments that may help explain some of the observed patterns of continental margin sediment instability. The processes associated with formation and decomposition of gas hydrate can cause the strengthening of sediments in which gas hydrate grow and the weakening of sediments in which gas hydrate decomposes. The weakened sediments may form horizons along which the potential for sediment failure is increased. While a causal relationship between slope failures and gas hydrate decomposition has not been proven, a number of empirical observations support their potential connection.

  13. Climate sensitivity and macronutrient regulation of peat decomposition

    NASA Astrophysics Data System (ADS)

    Marshall, Rachel; Ostle, Nick; McNamara, Niall; Baggs, Elizabeth

    2013-04-01

    Organic soils act as vital global carbon stores maintained in northern latitudes by climate and nutrient limited rates of organic matter decomposition. Peatland decomposition rates are sensitive to climate change, however predicting the magnitude of the microbial respiratory response is complex due to unknown interactions between climate and substrate quality. The nutrient status of peatlands varies widely from mineral rich fens to nutrient poor ombrotrophic bogs, which have the potential to respond differently to climate driven changes in temperature and carbon (C) inputs. In this work we examine the links between peatland macronutrient C, phosphorus (P) and nitrogen (N) stoichiometry, microbial community structure and the microbial response to direct and indirect effects of climate change. Using total soil C:N and C:P ratios to define nutrient gradients in organic soils from Svalbard and Finland we investigated the interaction between the microbial response to temperature and nutrient limitation of decomposition. In organic rich soils from Svalbard we found there was a significant relationship between increasing temperature sensitivity of respiration and decreasing total soil P concentrations. Further investigation of the potential direct link between P limitation of decomposition and increased temperature sensitivity along a minerotrophic-ombroptrophic gradient in Finland was performed using multi-factorial P limitation assays. These showed that despite varying degrees of P limitation across four peatland soils there was no relationship between P limitation and increased temperature sensitivity of soil respiration. Throughout this study we found consistently high temperature sensitivity of decomposition in organic rich soils with Q10 values ranging between 2 to 4.5, indicating potentially higher vulnerability of these C stores to warming than is currently predicted using a globally invariant Q10. Following on from this we examined the interaction between peatland nutrient status and the potential for labile C substrates to stimulate (prime) decomposition of the peat organic matter. Using 13C labelled glucose and hemicellulose compounds we observed significant differences in the amount and rate of microbial substrate use between peats with differing nutrient status. Nutrient addition experiments were used with labelled C substrates to investigate the role of N and P limitation in enhancing or restricting priming effects. This is one of the first studies to use 13C substrates to examine potential priming effects in peat soil and it provides an insight into the importance of priming mechanisms in peat decomposition. This work explicitly links soil microbial responses to temperature and nutrient manipulations with microbial community structure allowing us to observe how microbial communities mediate soil C losses in peat soils. Disentangling the complex interactions between soil microbial community, C and nutrient limitation of decomposition is essential for predicting the vulnerability of different peatland ecosystems to climate driven changes.

  14. Early Science with the Large Millimeter Telescope: Observations of dust continuum and CO emission lines of cluster-lensed submillimetre galaxies at z=2.0-4.7

    E-print Network

    Zavala, J A; Aretxaga, I; Hughes, D H; Wilson, G W; Geach, J E; Egami, E; Gurwell, M A; Wilner, D J; Smail, Ian; Blain, A W; Chapman, S C; Coppin, K E K; Dessauges-Zavadsky, M; Edge, A C; Montana, A; Nakajima, K; Rawle, T D; Sanchez-Arguelles, D; Swinbank, A M; Webb, T M A; Zeballos, M

    2015-01-01

    We present Early Science observations with the Large Millimeter Telescope, AzTEC 1.1 mm continuum images and wide bandwidth spectra (73-111 GHz) acquired with the Redshift Search Receiver (RSR), towards four bright lensed submillimetre galaxies identified through the Herschel Lensing Survey-snapshot and the SCUBA-2 Cluster Snapshot Survey. This pilot project studies the star formation history and the physical properties of the molecular gas and dust content of the highest redshift galaxies identified through the benefits of gravitational magnification. We robustly detect dust continuum emission for the full sample and CO emission lines for three of the targets. We find that one source shows spectroscopic multiplicity and is a blend of three galaxies at different redshifts (z=2.040, 3.252 and 4.680), reminiscent of previous high-resolution imaging follow-up of unlensed submillimetre galaxies, but with a completely different search method, that confirm recent theoretical predictions of physically unassociated b...

  15. Subaru/COMICS Mid-Infrared Observation of the Near-Nucleus Region of Comet 17P/Holmes at the Early Phase of an Outburst

    NASA Astrophysics Data System (ADS)

    Watanabe, Jun-Ichi; Honda, Mitsuhiko; Ishiguro, Masateru; Ootsubo, Takafumi; Sarugaku, Yuki; Kadono, Toshihiko; Sakon, Itsuki; Fuse, Tetsuharu; Takato, Naruhisa; Furusho, Reiko

    2009-08-01

    Mid-infrared 8--25?m imaging and spectroscopic observations of the comet 17P/Holmes in the early phase of its outburst in brightness were performed on 2007 October 25--28UT using the Cooled Mid-Infrared Camera and Spectrometer (COMICS) on the 8.2-m Subaru Telescope. We detected an isolated dust cloud that moved toward the south-west direction from the nucleus. The 11.2?m peak of a crystalline silicate feature onto a broad amorphous silicate feature was also detected both in the central condensation of the nucleus and an isolated dust cloud. The color temperature of the isolated dust cloud was estimated to be ˜200K, which is slightly higher than the black-body temperature. Our analysis of the motion indicates that the isolated cloud moved anti-sunward. We propose several possibilities for the motion of the cloud: fluffy dust particles in the isolated cloud started to depart from the nucleus due to radiation pressure almost as soon as the main outburst occurred, or dust particles moved by some other anti-sunward forces, such as a rocket effect and photophoresis when the surrounding dust coma became optically thin. The origin and the nature of the isolated dust cloud are discussed in this paper.

  16. Researches on the Nankai trough mega thrust earthquake seismogenic zones using real time observing systems for advanced early warning systems and predictions

    NASA Astrophysics Data System (ADS)

    Kaneda, Yoshiyuki

    2015-04-01

    We recognized the importance of real time monitoring on Earthquakes and Tsunamis Based on lessons learned from 2004 Sumatra Earthquake/Tsunamis and 2011 East Japan Earthquake. We deployed DONET1 and are developing DONET2 as real time monitoring systems which are dense ocean floor networks around the Nankai trough seismogenic zone Southwestern Japan. Total observatories of DONE1 and DONET2 are 51 observatories equipped with multi kinds of sensors such as the accelerometer, broadband seismometer, pressure gauge, difference pressure gauge, hydrophone and thermometer in each observatory. These systems are indispensable for not only early warning of Earthquakes/ Tsunamis, but also researches on broadband crustal activities around the Nankai trough seismogenic zone for predictions. DONET1 detected offshore tsunamis 15 minutes earlier than onshore stations at the 2011 East Japan earthquake/tsunami. Furthermore, DONET1/DONET2 will be expected to monitor slow events such as low frequency tremors and slow earthquakes for the prediction researches. Finally, the integration of observations and simulation researches will contribute to estimate of seismic stage changes from the inter-seismic to pre seismic stage. I will introduce applications of DONET1/DONET2 data and advanced simulation researches.

  17. Early Science with the Large Millimeter Telescope: observations of dust continuum and CO emission lines of cluster-lensed submillimetre galaxies at z=2.0-4.7

    NASA Astrophysics Data System (ADS)

    Zavala, J. A.; Yun, M. S.; Aretxaga, I.; Hughes, D. H.; Wilson, G. W.; Geach, J. E.; Egami, E.; Gurwell, M. A.; Wilner, D. J.; Smail, Ian; Blain, A. W.; Chapman, S. C.; Coppin, K. E. K.; Dessauges-Zavadsky, M.; Edge, A. C.; Montaña, A.; Nakajima, K.; Rawle, T. D.; Sánchez-Argüelles, D.; Swinbank, A. M.; Webb, T. M. A.; Zeballos, M.

    2015-09-01

    We present Early Science observations with the Large Millimeter Telescope, AzTEC 1.1 mm continuum images and wide bandwidth spectra (73-111 GHz) acquired with the Redshift Search Receiver, towards four bright lensed submillimetre galaxies identified through the Herschel Lensing Survey-snapshot and the Submillimetre Common-User Bolometer Array-2 Cluster Snapshot Survey. This pilot project studies the star formation history and the physical properties of the molecular gas and dust content of the highest redshift galaxies identified through the benefits of gravitational magnification. We robustly detect dust continuum emission for the full sample and CO emission lines for three of the targets. We find that one source shows spectroscopic multiplicity and is a blend of three galaxies at different redshifts (z = 2.040, 3.252, and 4.680), reminiscent of previous high-resolution imaging follow-up of unlensed submillimetre galaxies, but with a completely different search method, that confirm recent theoretical predictions of physically unassociated blended galaxies. Identifying the detected lines as 12CO (Jup = 2-5) we derive spectroscopic redshifts, molecular gas masses, and dust masses from the continuum emission. The mean H2 gas mass of the full sample is (2.0 ± 0.2) × 1011 M?/?, and the mean dust mass is (2.0 ± 0.2) × 109 M?/?, where ? ? 2-5 is the expected lens amplification. Using these independent estimations we infer a gas-to-dust ratio of ?GDR ? 55-75, in agreement with other measurements of submillimetre galaxies. Our magnified high-luminosity galaxies fall on the same locus as other high-redshift submillimetre galaxies, extending the L^' }_CO-LFIR correlation observed for local luminous and ultraluminous infrared galaxies to higher far-infrared and CO luminosities.

  18. SeismoGeodesy: Combination of High Rate, Real-time GNSS and Accelerometer Observations and Rapid Seismic Event Notification for Earth Quake Early Warning and Volcano Monitoring

    NASA Astrophysics Data System (ADS)

    Jackson, Michael; Zimakov, Leonid; Moessmer, Matthias

    2015-04-01

    Scientific GNSS networks are moving towards a model of real-time data acquisition, epoch-by-epoch storage integrity, and on-board real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-rate GNSS displacement information with acceleration and velocity data to create very high-rate displacement records. The mating of these two instruments allows the creation of a new, very high-rate (200 Hz) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for earthquake early warning studies, volcano monitoring, and critical infrastructure monitoring applications. Our presentation will focus on the characteristics of GNSS, seismic, and strong motion sensors in high dynamic environments, including historic earthquakes replicated on a shake table over a range of displacements and frequencies. We will explore the optimum integration of these sensors from a filtering perspective including simple harmonic impulses over varying frequencies and amplitudes and under the dynamic conditions of various earthquake scenarios. We will also explore the tradeoffs between various GNSS processing schemes including real-time precise point positioning (PPP) and real-time kinematic (RTK) as applied to seismogeodesy. In addition we will discuss implementation of a Rapid Seismic Event Notification System that provides quick delivery of digital data from seismic stations to the acquisition and processing center and a full data integrity model for real-time earthquake notification that provides warning prior to significant ground shaking.

  19. A new seismogeodetic approach applied to GPS and accelerometer observations of the 2012 Brawley seismic swarm: Implications for earthquake early warning

    NASA Astrophysics Data System (ADS)

    Geng, Jianghui; Bock, Yehuda; Melgar, Diego; Crowell, Brendan W.; Haase, Jennifer S.

    2013-07-01

    The 26 August 2012 Brawley seismic swarm of hundreds of events ranging from M1.4 to M5.5 in the Salton Trough, California provides a unique data set to investigate a new seismogeodetic approach that combines Global Positioning System (GPS) and accelerometer observations to estimate displacement and velocity waveforms. First in simulated real-time mode, we analyzed 1-5 Hz GPS data collected by 17 stations fully encircling the swarm zone at near-source distances up to about 40 km using precise point positioning with ambiguity resolution (PPP-AR). We used a reference network of North American GPS stations well outside the region of deformation to estimate fractional-cycle biases and satellite clock parameters, which were then combined with ultrarapid orbits from the International GNSS Service to estimate positions during the Brawley seismic swarm. Next, we estimated seismogeodetic displacements and velocities from GPS phase and pseudorange observations and 100-200 Hz accelerations collected at three pairs of GPS and seismic stations in close proximity using a new tightly coupled Kalman filter approach as an extension of the PPP-AR process. We can clearly discern body waves in the velocity waveforms, including P-wave arrivals not detectable with the GPS-only approach for earthquake magnitudes as low as Mw 4.6 and significant static offsets for magnitudes as low as Mw 5.4. Our study shows that GPS networks upgraded with strong motion accelerometers can provide new information for improved understanding of the earthquake rupture process and be of critical value in creating a robust early warning system for any earthquake of societal significance.

  20. Chunk decomposition contributes to forming new mental representations: An ERP study.

    PubMed

    Zhang, Zhonglu; Xing, Qiang; Li, Hong; Warren, Christopher Michael; Tang, Zhiwen; Che, Jingshang

    2015-06-26

    Whereas previous studies mainly focused on the role of chunk decomposition on how to break impasse in insight occurrence, our study aimed to investigate the role of chunk decomposition in forming new mental representations. For this purpose, the Chinese riddle comprehension task was employed in which the riddle involves either tight or loose chunk decomposition. The event-related potentials (ERPs) were measured after the onset of an answer hint, with which participants were instructed to comprehend the Chinese riddles. The behavioral results showed that participants performed worse on riddle comprehension in tight chunk condition than in loose chunk condition. In addition, we found larger N100 and P300 deflections in the former condition than in the latter condition. These findings suggest that early perceptual processing is crucially required by chunk decomposition, which contributes to forming new mental representations by integrating the perceptual and semantic information. PMID:25957557

  1. Variance decomposition in stochastic simulators.

    PubMed

    Le Maître, O P; Knio, O M; Moraes, A

    2015-06-28

    This work aims at the development of a mathematical and computational approach that enables quantification of the inherent sources of stochasticity and of the corresponding sensitivities in stochastic simulations of chemical reaction networks. The approach is based on reformulating the system dynamics as being generated by independent standardized Poisson processes. This reformulation affords a straightforward identification of individual realizations for the stochastic dynamics of each reaction channel, and consequently a quantitative characterization of the inherent sources of stochasticity in the system. By relying on the Sobol-Hoeffding decomposition, the reformulation enables us to perform an orthogonal decomposition of the solution variance. Thus, by judiciously exploiting the inherent stochasticity of the system, one is able to quantify the variance-based sensitivities associated with individual reaction channels, as well as the importance of channel interactions. Implementation of the algorithms is illustrated in light of simulations of simplified systems, including the birth-death, Schlögl, and Michaelis-Menten models. PMID:26133418

  2. Nucleon Momentum Decomposition in QCD

    E-print Network

    Y. M. Cho; Mo-Lin Ge; D. G. Pak; Pengming Zhang

    2011-04-29

    ~Based on the gauge invariant quark canonical momentum we construct two theoretically possible decompositions of nucleon momentum to those of quarks and gluons. We predict that either 6% or 21% of nucleon momentum is carried by gluons, depending on what type of gluons are in nucleons. We clarify the existing confusions on this problem and discuss the physical implications of our result on the proton spin crisis problem.

  3. Phlogopite Decomposition, Water, and Venus

    NASA Technical Reports Server (NTRS)

    Johnson, N. M.; Fegley, B., Jr.

    2005-01-01

    Venus is a hot and dry planet with a surface temperature of 660 to 740 K and 30 parts per million by volume (ppmv) water vapor in its lower atmosphere. In contrast Earth has an average surface temperature of 288 K and 1-4% water vapor in its troposphere. The hot and dry conditions on Venus led many to speculate that hydrous minerals on the surface of Venus would not be there today even though they might have formed in a potentially wetter past. Thermodynamic calculations predict that many hydrous minerals are unstable under current Venusian conditions. Thermodynamics predicts whether a particular mineral is stable or not, but we need experimental data on the decomposition rate of hydrous minerals to determine if they survive on Venus today. Previously, we determined the decomposition rate of the amphibole tremolite, and found that it could exist for billions of years at current surface conditions. Here, we present our initial results on the decomposition of phlogopite mica, another common hydrous mineral on Earth.

  4. Determination of value of bovine respiratory disease control using a remote early disease identification system compared with conventional methods of metaphylaxis and visual observations.

    PubMed

    White, B J; Amrine, D E; Goehl, D R

    2015-08-01

    Mitigation of the deleterious effects of bovine respiratory disease (BRD) is an important issue in the cattle industry. Conventional management of calves at high risk for BRD often includes mass treatment with antimicrobials at arrival followed by visual observation for individual clinical cases. These methods have proven effective; however, control program efficacy is influenced by the accuracy of visual observation. A remote early disease identification (REDI) system has been described that monitors cattle behavior to identify potential BRD cases. The objective of this research was to compare health and performance outcomes using either traditional BRD control (visual observation and metaphylaxis) or REDI during a 60-d postarrival phase in high-risk beef calves. The randomized controlled clinical trial was performed in 8 replicates at 3 different facilities over a 19-mo period. In each replicate, a single load of calves was randomly allocated to receive either conventional management (CONV; total = 8) or REDI (total = 8) as the method for BRD control. Cattle were monitored with each diagnostic method for the first 30 d on feed and performance variables were collected until approximately 60 d after arrival. Statistical differences ( < 0.10) were not identified in common performance (ADG) or health (morbidity, first treatment success, and mortality risk) among the treatment groups. Calves in the REDI pens had a lower ( < 0.01) average number of days on feed at first treatment (9.1 ± 1.2 d) compared with CONV pens (15.8 ± 1.2 d). There were no statistical differences ( > 0.10) in risk of BRD treatment and REDI calves were not administered antimicrobials at arrival; therefore, REDI calves had a lower ( < 0.01) average number of doses of antimicrobials/calf (0.75 ± 0.1 doses) compared with CONV calves (1.67 ± 0.1 doses). In this trial, the REDI system was comparable to conventional management with the potential advantages of earlier BRD diagnosis and decreased use of antimicrobials. Further research should be performed to evaluate the longer-term impacts of the 2 systems. PMID:26440191

  5. GC?×?GC-TOFMS and supervised multivariate approaches to study human cadaveric decomposition olfactive signatures.

    PubMed

    Stefanuto, Pierre-Hugues; Perrault, Katelynn A; Stadler, Sonja; Pesesse, Romain; LeBlanc, Helene N; Forbes, Shari L; Focant, Jean-François

    2015-06-01

    In forensic thanato-chemistry, the understanding of the process of soft tissue decomposition is still limited. A better understanding of the decomposition process and the characterization of the associated volatile organic compounds (VOC) can help to improve the training of victim recovery (VR) canines, which are used to search for trapped victims in natural disasters or to locate corpses during criminal investigations. The complexity of matrices and the dynamic nature of this process require the use of comprehensive analytical methods for investigation. Moreover, the variability of the environment and between individuals creates additional difficulties in terms of normalization. The resolution of the complex mixture of VOCs emitted by a decaying corpse can be improved using comprehensive two-dimensional gas chromatography (GC?×?GC), compared to classical single-dimensional gas chromatography (1DGC). This study combines the analytical advantages of GC?×?GC coupled to time-of-flight mass spectrometry (TOFMS) with the data handling robustness of supervised multivariate statistics to investigate the VOC profile of human remains during early stages of decomposition. Various supervised multivariate approaches are compared to interpret the large data set. Moreover, early decomposition stages of pig carcasses (typically used as human surrogates in field studies) are also monitored to obtain a direct comparison of the two VOC profiles and estimate the robustness of this human decomposition analog model. In this research, we demonstrate that pig and human decomposition processes can be described by the same trends for the major compounds produced during the early stages of soft tissue decomposition. PMID:25910882

  6. Decreases in Soil Moisture and Organic Matter Quality Suppress Microbial Decomposition Following a Boreal Forest Fire

    SciTech Connect

    Holden, Sandra R.; Berhe, Asmeret A.; Treseder, Kathleen K.

    2015-08-01

    Climate warming is projected to increase the frequency and severity of wildfires in boreal forests, and increased wildfire activity may alter the large soil carbon (C) stocks in boreal forests. Changes in boreal soil C stocks that result from increased wildfire activity will be regulated in part by the response of microbial decomposition to fire, but post-fire changes in microbial decomposition are poorly understood. Here, we investigate the response of microbial decomposition to a boreal forest fire in interior Alaska and test the mechanisms that control post-fire changes in microbial decomposition. We used a reciprocal transplant between a recently burned boreal forest stand and a late successional boreal forest stand to test how post-fire changes in abiotic conditions, soil organic matter (SOM) composition, and soil microbial communities influence microbial decomposition. We found that SOM decomposing at the burned site lost 30.9% less mass over two years than SOM decomposing at the unburned site, indicating that post-fire changes in abiotic conditions suppress microbial decomposition. Our results suggest that moisture availability is one abiotic factor that constrains microbial decomposition in recently burned forests. In addition, we observed that burned SOM decomposed more slowly than unburned SOM, but the exact nature of SOM changes in the recently burned stand are unclear. Finally, we found no evidence that post-fire changes in soil microbial community composition significantly affect decomposition. Taken together, our study has demonstrated that boreal forest fires can suppress microbial decomposition due to post-fire changes in abiotic factors and the composition of SOM. Models that predict the consequences of increased wildfires for C storage in boreal forests may increase their predictive power by incorporating the observed negative response of microbial decomposition to boreal wildfires.

  7. Decomposition-Based Decision Making for Aerospace Vehicle Design

    NASA Technical Reports Server (NTRS)

    Borer, Nicholas K.; Mavris, DImitri N.

    2005-01-01

    Most practical engineering systems design problems have multiple and conflicting objectives. Furthermore, the satisfactory attainment level for each objective ( requirement ) is likely uncertain early in the design process. Systems with long design cycle times will exhibit more of this uncertainty throughout the design process. This is further complicated if the system is expected to perform for a relatively long period of time, as now it will need to grow as new requirements are identified and new technologies are introduced. These points identify a need for a systems design technique that enables decision making amongst multiple objectives in the presence of uncertainty. Traditional design techniques deal with a single objective or a small number of objectives that are often aggregates of the overarching goals sought through the generation of a new system. Other requirements, although uncertain, are viewed as static constraints to this single or multiple objective optimization problem. With either of these formulations, enabling tradeoffs between the requirements, objectives, or combinations thereof is a slow, serial process that becomes increasingly complex as more criteria are added. This research proposal outlines a technique that attempts to address these and other idiosyncrasies associated with modern aerospace systems design. The proposed formulation first recasts systems design into a multiple criteria decision making problem. The now multiple objectives are decomposed to discover the critical characteristics of the objective space. Tradeoffs between the objectives are considered amongst these critical characteristics by comparison to a probabilistic ideal tradeoff solution. The proposed formulation represents a radical departure from traditional methods. A pitfall of this technique is in the validation of the solution: in a multi-objective sense, how can a decision maker justify a choice between non-dominated alternatives? A series of examples help the reader to observe how this technique can be applied to aerospace systems design and compare the results of this so-called Decomposition-Based Decision Making to more traditional design approaches.

  8. Impact of radiotherapy technique on the outcome of early breast cancer treated with conservative surgery: A multicenter observational study on 1,176 patients

    SciTech Connect

    Palazzi, Mauro . E-mail: mauro.palazzi@istitutotumori.mi.it; Tomatis, Stefano; Valli, Maria Carla; Guzzetti, Renata; Tonoli, Sandro; Bertoni, Filippo; Magrini, Stefano Maria; Meregalli, Sofia; Asnaghi, Diego; Arienti, Virginia; Pradella, Renato; Cafaro, Ines

    2006-08-01

    Purpose: To quantify the impact of radiotherapy technique on cosmetic outcome and on 5-year local control rate of early breast cancer treated with conservative surgery and adjuvant radiation. Methods and MaterialsPurpose: A total of 1,176 patients irradiated to the breast in 1997 were entered by eight centers into a prospective, observational study. Surgical procedure was quadrantectomy in 97% of patients, with axillary dissection performed in 96%; pT-stage was T1 in 81% and T2 in 19% of cases; pN-stage was N0 in 71%, N + (1-3) in 21%, and N + (>3) in 8% of cases. An immobilization device was used in 17% of patients; external contour-based and computed tomography-based treatment planning were performed in 20% and 72% of cases, respectively; 37% of patients were treated with a telecobalt unit and 63% with a linear accelerator; portal verification was used in 55% of patients; a boost dose to the tumor bed was delivered in 60% of cases. Results: With a median follow-up of 6.2 years, local, regional, and distant control rates at 5 years are 98%, 99%, and 92%, respectively. Use of less sophisticated treatment technique was associated with a less favorable cosmetic outcome. Local control was comparable between centers despite substantial technical differences. In a multivariate analysis including clinical and technical factors, only older age and prescription of medical adjuvant treatment significantly predicted for better local control, whereas use of portal verification was of borderline significance. Conclusions: Radiation technical factors impacted negatively on cosmetic outcome, but had relatively small effects on local control compared with other clinical factors.

  9. Stellar Populations of Lyman Break Galaxies at z approx. to 1-3 in the HST/WFC3 Early Release Science Observations

    NASA Technical Reports Server (NTRS)

    Hathi, N. P.; Cohen, S. H.; Ryan, R. E., Jr.; Finkelstein, S. L.; McCarthy, P. J.; Windhorst, R. A.; Yan, H.; Koekemoer, A. M.; Rutkowski, M. J.; OConnell, R. W.; Straughn, A. N.; Balick, B.; Bond, H. E.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; Kimble, R. A.; Paresce, F.; Saha, A.; Silk, J. I.; Tauger, J. T.; Young, E. T.

    2012-01-01

    We analyze the spectral energy distributions (SEDs) of Lyman break galaxies . (LBGs) at z approx = 1-3 selected using the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) UVIS channel filters. These HST /WFC3 obse,rvations cover about 50 arcmin2 in the GOODS-South field as a part of the WFC3 Early Release Science program. These LBGs at z approx = 1-3 are selected using dropout selection criteria similar to high redshift LBGs. The deep multi-band photometry in this field is used to identify best-fit SED models, from which we infer the following results: (1) the photometric redshift estimate of these dropout selected LBGs is accurate to within few percent; (2) the UV spectral slope f3 is redder than at high redshift (z > 3), where LBGs are less dusty; (3) on average, LBGs at .z approx = 1-3 are massive, dustier and more highly star-forming, compared to LBGs at higher redshifts with similar luminosities, though their median values are similar within 1a uncertainties. This could imply that identical dropout selection technique, at all. redshifts, find physically similar galaxies; and (4) the stellar masses of these LBGs are directly proportional to their UV luminosities with a logarithmic slope of approx 0.46, and star-formation rates are proportional to their stellar masses with a logarithmic slope of approx 0.90. These relations hold true - within luminosities probed in this study - for LBGs from z approx = 1.5 to 5. The star-forming galaxies selected using other color-based techniques show similar correlations at z approx = 2, but to avoid any selection biases, and for direct comparison with LBGs at z > 3, a true Lyman break selection at z approx = 2 is essential. The future HST UV surveys,. both wider and deeper, covering a large luminosity range are important to better understand LBG properties, and their evolution.

  10. Impact of prior CKD management in a renal care network on early outcomes in incident dialysis patients: a prospective observational study

    PubMed Central

    2013-01-01

    Background Effective therapeutic strategies are available to prevent adverse outcomes in patients with chronic kidney disease (CKD) but their clinical results are hindered by unplanned implementation. Coordination of care emerges as a suitable way to improve patient outcomes. In this study, we evaluated the effect of planned and coordinated patient management within a dedicated renal care network comparatively to standard renal care delivered in nephrology departments of teaching hospitals. Methods This observational matched cohort study included 40 patients with CKD stage 4–5 in the network group as compared with a control group of 120 patients matched for age, sex and diabetic status. Main outcome was a composite endpoint of death from cardiovascular cause and cardiovascular events during the first year after dialysis initiation. Results There was no difference between the two groups neither for the primary outcome (40% vs 41%) nor for the occurrence of death from cardiovascular cause or cardiovascular events. Whereas the proportion of patients requiring at least one hospitalization was identical (83.3% vs 75%), network patients experienced less individual hospitalizations than control patients (2.3±2.0 vs 1.6±1.7) during the year before dialysis start. Patients of the network group had a slower renal function decline (7.7±2.5 vs 4.9±1.1 ml/min/1,73m2 per year; p=0.04). Conclusions In this limited series of patients, we were unable to demonstrate a significant impact of the coordinated renal care provided in the network on early cardiovascular events in incident dialysis patients. However, during the predialysis period, there were less hospitalizations and a slower slope of renal function decrease. PMID:23425313

  11. El Mayor-Cucapah (Mw 7.2) earthquake: Early near-field postseismic deformation from InSAR and GPS observations

    NASA Astrophysics Data System (ADS)

    Gonzalez-Ortega, Alejandro; Fialko, Yuri; Sandwell, David; Alejandro Nava-Pichardo, F.; Fletcher, John; Gonzalez-Garcia, Javier; Lipovsky, Brad; Floyd, Michael; Funning, Gareth

    2014-02-01

    El Mayor-Cucapah earthquake occurred on 4 April 2010 in northeastern Baja California just south of the U.S.-Mexico border. The earthquake ruptured several previously mapped faults, as well as some unidentified ones, including the Pescadores, Borrego, Paso Inferior and Paso Superior faults in the Sierra Cucapah, and the Indiviso fault in the Mexicali Valley and Colorado River Delta. We conducted several Global Positioning System (GPS) campaign surveys of preexisting and newly established benchmarks within 30 km of the earthquake rupture. Most of the benchmarks were occupied within days after the earthquake, allowing us to capture the very early postseismic transient motions. The GPS data show postseismic displacements in the same direction as the coseismic displacements; time series indicate a gradual decay in postseismic velocities with characteristic time scales of 66 ± 9 days and 20 ± 3 days, assuming exponential and logarithmic decay, respectively. We also analyzed interferometric synthetic aperture radar (InSAR) data from the Envisat and ALOS satellites. The main deformation features seen in the line-of-sight displacement maps indicate subsidence concentrated in the southern and northern parts of the main rupture, in particular at the Indiviso fault, at the Laguna Salada basin, and at the Paso Superior fault. We show that the near-field GPS and InSAR observations over a time period of 5 months after the earthquake can be explained by a combination of afterslip, fault zone contraction, and a possible minor contribution of poroelastic rebound. Far-field data require an additional mechanism, most likely viscoelastic relaxation in the ductile substrate.

  12. Nuclei fluorescence microscopic observation on early embryonic development of mitogynogenetic diploid induced by hydrostatic pressure treatment in olive flounder (Paralichthys olivaceus).

    PubMed

    Lin, Zhengmei; Zhu, Xiangping; You, Feng; Wu, Zhihao; Cao, Yuanshui

    2015-05-01

    Sperm genetic material of olive flounder (Paralichthys olivaceus) was inactivated by ultraviolet irradiation. The nuclear phase changes during early embryonic development of diploid, haploid, and mitogynogenetic diploid induced by hydrostatic pressure treatment were observed under fluorescent microscope with 4',6-diamidino-2-phenylindole staining. The parameters of hydrostatic pressure treatment were 600 kg/cm(2) for 6 minutes at prometaphase stage. The data showed that developmental timing sequence of diploid and haploid fertilized eggs was similar. The cell cycle was about 48 minutes, including interphase (about 21 minutes), prophase (about 3 minutes), prometaphase (about 6 minutes), metaphase (about 6 minutes), anaphase (around 9 minutes), and telophase (about 3 minutes). After entering the fertilized egg, ultraviolet-inactivated sperm formed a male pronucleus and became a dense chromatin body in the cytoplasm. Dense chromatin body did not participate in nuclear division and unchanged all the time. For hydrostatic pressure-treated embryos, the first nuclear division and cytokinesis after treatment proceeded normally after about 15 minutes recovery. During the second mitosis, having undergone interphase, prophase, and prometaphase stage, chromosomes began to slowly spread around and scattered in the cell but not entered into metaphase and anaphase. The second nuclear division and cytokinesis was inhibited. The occurrence frequency of developmentally delayed embryos also showed that the second cleavage of about 80% treated eggs was inhibited. The inhibition of the second cleavage resulted to chromosome set doubling. So chromosome set doubling for mitogynogenetic flounder diploid induced by hydrostatic pressure treatment, performed at prometaphase stage, was mainly due to inhibition of the second mitosis rather than the first one. PMID:25726149

  13. SPECTROSCOPIC OBSERVATIONS OF SN 2012fr: A LUMINOUS, NORMAL TYPE Ia SUPERNOVA WITH EARLY HIGH-VELOCITY FEATURES AND A LATE VELOCITY PLATEAU

    SciTech Connect

    Childress, M. J.; Scalzo, R. A.; Sim, S. A.; Tucker, B. E.; Yuan, F.; Schmidt, B. P.; Cenko, S. B.; Filippenko, A. V.; Silverman, J. M.; Contreras, C.; Hsiao, E. Y.; Phillips, M.; Morrell, N.; Jha, S. W.; McCully, C.; Anderson, J. P.; De Jaeger, T.; Forster, F.; Benetti, S.; Bufano, F.; and others

    2013-06-10

    We present 65 optical spectra of the Type Ia SN 2012fr, 33 of which were obtained before maximum light. At early times, SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II {lambda}6355 line that can be cleanly decoupled from the lower velocity ''photospheric'' component. This Si II {lambda}6355 HVF fades by phase -5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of {approx}12,000 km s{sup -1} until at least five weeks after maximum brightness. The Ca II infrared triplet exhibits similar evidence for both a photospheric component at v Almost-Equal-To 12,000 km s{sup -1} with narrow line width and long velocity plateau, as well as an HVF beginning at v Almost-Equal-To 31,000 km s{sup -1} two weeks before maximum. SN 2012fr resides on the border between the ''shallow silicon'' and ''core-normal'' subclasses in the Branch et al. classification scheme, and on the border between normal and high-velocity Type Ia supernovae (SNe Ia) in the Wang et al. system. Though it is a clear member of the ''low velocity gradient'' group of SNe Ia and exhibits a very slow light-curve decline, it shows key dissimilarities with the overluminous SN 1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observed SN Ia at the luminous end of the normal SN Ia distribution and a key transitional event between nominal spectroscopic subclasses of SNe Ia.

  14. Spatial filter decomposition for interference mitigation

    NASA Astrophysics Data System (ADS)

    Maoudj, Rabah; Terre, Michel; Fety, Luc; Alexandre, Christophe; Mege, Philippe

    2014-12-01

    This paper presents a two-part decomposition of a spatial filter having to optimize the reception of a useful signal in the presence of an important co-channel interference level. The decomposition highlights the role of two parts of the filter, one devoted to the maximization of the signal to noise ratio and the other devoted to the interference cancellation. The two-part decomposition is used in the estimation process of the optimal reception filter. We propose then an estimation algorithm that follows this decomposition, and the global spatial filter is finally obtained through an optimal-weighted combination of two filters. It is shown that this two-component-based decomposition algorithm overcomes other previously published solutions involving eigenvalue decompositions.

  15. Fischer decomposition for polynomials on superspace

    E-print Network

    Roman Lavicka; Dalibor Smid

    2015-08-14

    Recently, the Fischer decomposition for polynomials on superspace R^{m|2n} (that is, polynomials in m commuting and 2n anti-commuting variables) has been obtained unless the superdimension M=m-2n is even and non-positive. In this case, it turns out that the Fischer decomposition of polynomials into spherical harmonics is quite analogous as in R^m and it is an irreducible decomposition under the natural action of Lie superalgebra osp(m|2n). In this paper, we describe explicitly the Fischer decomposition in the exceptional case when M is even and non-positive. In particular, we show that, under the action of osp(m|2n), the Fischer decomposition is not, in general, a decomposition into irreducible but indecomposable pieces.

  16. Fischer decomposition for polynomials on superspace

    NASA Astrophysics Data System (ADS)

    Lávi?ka, Roman; Šmíd, Dalibor

    2015-11-01

    Recently, the Fischer decomposition for polynomials on superspace ?m|2n (that is, polynomials in m commuting and 2n anti-commuting variables) has been obtained unless the superdimension M = m - 2n is even and non-positive. In this case, it turns out that the Fischer decomposition of polynomials into spherical harmonics is quite analogous as in ?m and it is an irreducible decomposition under the natural action of Lie superalgebra 𝔬𝔰𝔭(m|2n). In this paper, we describe explicitly the Fischer decomposition in the exceptional case when M ? - 2?0. In particular, we show that, under the action of 𝔬𝔰𝔭(m|2n), the Fischer decomposition is not, in general, a decomposition into irreducible but just indecomposable pieces.

  17. Reaction sequence and kinetics of uranium nitride decomposition.

    PubMed

    Silva, G W Chinthaka; Yeamans, Charles B; Sattelberger, Alfred P; Hartmann, Thomas; Cerefice, Gary S; Czerwinski, Kenneth R

    2009-11-16

    The reaction mechanism and kinetics of the thermal decomposition of uranium dinitride/uranium sesquinitride to uranium mononitride under inert atmosphere at elevated temperature were studied. An increase in the lattice parameter of the UN(2)/alpha-U(2)N(3) phase was observed as the reaction temperature increased, corresponding to a continuous removal of nitrogen. Electron density calculations for these two compounds using XRD powder patterns of the samples utilizing charge-flipping technique were performed for the first time to visualize the decrease in nitrogen level as a function of temperature. Complete decomposition of UN(2) into alpha-U(2)N(3) at 675 degrees C and the UN formation after a partial decomposition of alpha-U(2)N(3) at 975 degrees C were also identified in this study. The activation energy for the decomposition of the UN(2)/alpha-U(2)N(3) phase into UN, 423.8 +/- 0.3 kJ/mol (101.3 kcal/mol), was determined under an inert argon atmosphere and is reported here experimentally for the first time. PMID:19845318

  18. Conductimetric determination of decomposition of silicate melts

    NASA Technical Reports Server (NTRS)

    Kroeger, C.; Lieck, K.

    1986-01-01

    A description of a procedure is given to detect decomposition of silicate systems in the liquid state by conductivity measurements. Onset of decomposition can be determined from the temperature curves of resistances measured on two pairs of electrodes, one above the other. Degree of decomposition can be estimated from temperature and concentration dependency of conductivity of phase boundaries. This procedure was tested with systems PbO-B2O3 and PbO-B2O3-SiO2.

  19. Consistent gauge invariant nucleon spin decomposition

    E-print Network

    D. G. Pak; P. M. Zhang

    2012-04-23

    We consider a non-uniqueness problem of gauge invariant nucleon spin decomposition. A gauge invariant decomposition with a generalized Coulomb constraint for the physical gluon has been constructed. The decomposition scheme is consistent with the concept of helicity in non-Abelian gauge theory. We provide an explicit representation for the gauge invariant Abelian projection which implies further separation of gluon into binding and valence parts.

  20. Symptoms during the Menopausal Transition and Early Postmenopause and their Relation to Endocrine Levels over Time: Observations from the Seattle Midlife Women's Health Study

    E-print Network

    Percival, Don

    1 Symptoms during the Menopausal Transition and Early Postmenopause and their Relation to Endocrine Applied Physics Laboratory, 3 Department of Biobehavioral Nursing and Health Systems, University of the menopausal transition were included in the analyses. Results: Correlations between endocrine levels

  1. On Schubert decompositions of quiver Grassmannians

    NASA Astrophysics Data System (ADS)

    Lorscheid, Oliver

    2014-02-01

    In this paper, we introduce Schubert decompositions for quiver Grassmannians and investigate certain classes of quiver Grassmannians with a Schubert decomposition into affine spaces. The main theorem puts the cells of a Schubert decomposition into relation to the cells of a certain simpler quiver Grassmannian. This allows us to extend known examples of Schubert decompositions into affine spaces to a larger class of quiver Grassmannians. This includes exceptional representations of the Kronecker quiver as well as representations of forests with block matrices of the form (0100). Finally, we draw conclusions on the Euler characteristics and the cohomology of quiver Grassmannians.

  2. Thermodynamic anomaly in magnesium hydroxide decomposition

    SciTech Connect

    Reis, T.A.

    1983-08-01

    The Origin of the discrepancy in the equilibrium water vapor pressure measurements for the reaction Mg(OH)/sub 2/(s) = MgO(s) + H/sub 2/O(g) when determined by Knudsen effusion and static manometry at the same temperature was investigated. For this reaction undergoing continuous thermal decomposition in Knudsen cells, Kay and Gregory observed that by extrapolating the steady-state apparent equilibrium vapor pressure measurements to zero-orifice, the vapor pressure was approx. 10/sup -4/ of that previously established by Giauque and Archibald as the true thermodynamic equilibrium vapor pressure using statistical mechanical entropy calculations for the entropy of water vapor. This large difference in vapor pressures suggests the possibility of the formation in a Knudsen cell of a higher energy MgO that is thermodynamically metastable by about 48 kJ / mole. It has been shown here that experimental results are qualitatively independent of the type of Mg(OH)/sub 2/ used as a starting material, which confirms the inferences of Kay and Gregory. Thus, most forms of Mg(OH)/sub 2/ are considered to be the stable thermodynamic equilibrium form. X-ray diffraction results show that during the course of the reaction only the equilibrium NaCl-type MgO is formed, and no different phases result from samples prepared in Knudsen cells. Surface area data indicate that the MgO molar surface area remains constant throughout the course of the reaction at low decomposition temperatures, and no significant annealing occurs at less than 400/sup 0/C. Scanning electron microscope photographs show no change in particle size or particle surface morphology. Solution calorimetric measurements indicate no inherent hgher energy content in the MgO from the solid produced in Knudsen cells. The Knudsen cell vapor pressure discrepancy may reflect the formation of a transient metastable MgO or Mg(OH)/sub 2/-MgO solid solution during continuous thermal decomposition in Knudsen cells.

  3. Nitrogen Addition Significantly Affects Forest Litter Decomposition under High Levels of Ambient Nitrogen Deposition

    PubMed Central

    Chen, Gang; Peng, Yong; Xiao, Yin-long; Hu, Ting-xing; Zhang, Jian; Li, Xian-wei; Liu, Li; Tang, Yi

    2014-01-01

    Background Forest litter decomposition is a major component of the global carbon (C) budget, and is greatly affected by the atmospheric nitrogen (N) deposition observed globally. However, the effects of N addition on forest litter decomposition, in ecosystems receiving increasingly higher levels of ambient N deposition, are poorly understood. Methodology/Principal Findings We conducted a two-year field experiment in five forests along the western edge of the Sichuan Basin in China, where atmospheric N deposition was up to 82–114 kg N ha–1 in the study sites. Four levels of N treatments were applied: (1) control (no N added), (2) low-N (50 kg N ha–1 year–1), (3) medium-N (150 kg N ha–1 year–1), and (4) high-N (300 kg N ha–1 year–1), N additions ranging from 40% to 370% of ambient N deposition. The decomposition processes of ten types of forest litters were then studied. Nitrogen additions significantly decreased the decomposition rates of six types of forest litters. N additions decreased forest litter decomposition, and the mass of residual litter was closely correlated to residual lignin during the decomposition process over the study period. The inhibitory effect of N addition on litter decomposition can be primarily explained by the inhibition of lignin decomposition by exogenous inorganic N. The overall decomposition rate of ten investigated substrates exhibited a significant negative linear relationship with initial tissue C/N and lignin/N, and significant positive relationships with initial tissue K and N concentrations; these relationships exhibited linear and logarithmic curves, respectively. Conclusions/Significance This study suggests that the expected progressive increases in N deposition may have a potential important impact on forest litter decomposition in the study area in the presence of high levels of ambient N deposition. PMID:24551152

  4. QR-decomposition The QR-decomposition of an n k matrix A, k n, is

    E-print Network

    Sleijpen, Gerard

    QR-decomposition The QR-decomposition of an n � k matrix A, k n, is an n � n unitary matrix Q and an n � k upper triangular matrix R for which A = QR In Matlab [Q,R]=qr(A); Note. The QR-decomposition is unique up to a change of signs of the columns of Q: A = (QD)( ¯DR) with |D| = I #12;QR-decomposition

  5. Inverse Laplace transform of rational functions using Partial Fraction Decomposition

    E-print Network

    Zelenko, Igor

    Inverse Laplace transform of rational functions using Partial Fraction Decomposition Using Fraction Decomposition The latter can be done by means of the partial fraction decomposition that you in the decomposition of Q(s) gives a contribution of certain type to the partial fraction decomposition of P(s) Q

  6. NEW SIMULTANEOUS GENERALIZED SCHUR DECOMPOSITION METHODS FOR THE COMPUTATION OF THE CANONICAL POLYADIC DECOMPOSITION

    E-print Network

    NEW SIMULTANEOUS GENERALIZED SCHUR DECOMPOSITION METHODS FOR THE COMPUTATION OF THE CANONICAL POLYADIC DECOMPOSITION Mikael Sørensen and Lieven De Lathauwer K.U.Leuven - E.E. Dept. (ESAT) - SCD) decomposition have been proposed. The original SGSD method re- quires that all three matrix factors of the CP

  7. COUPLED RANK-(Lm, Ln, ) BLOCK TERM DECOMPOSITION BY COUPLED BLOCK SIMULTANEOUS GENERALIZED SCHUR DECOMPOSITION

    E-print Network

    1 / 5 COUPLED RANK-(Lm, Ln, ·) BLOCK TERM DECOMPOSITION BY COUPLED BLOCK SIMULTANEOUS GENERALIZED SCHUR DECOMPOSITION Xiao-Feng Gong* , Qiu-Hua Lin*, Otto Debals§ , Nico Vervliet§ , Lieven De Lathauwer decompositions of multiple tensors are fundamental tools for multi-set data fusion. In this paper, we introduce

  8. Thermal decomposition of synthesised carbonate hydroxyapatite.

    PubMed

    Barralet, J; Knowles, J C; Best, S; Bonfield, W

    2002-06-01

    Heat treatments are used when sintering hydroxyapatite to make porous blocks and granules and during plasma spraying of coatings. Calcium : phosphorus ratio is known to affect the thermal decomposition behavior of hydroxyapatite. Hydroxyapatite with carbonate ions substituted for phosphate ions is more similar in composition to bone mineral. While it has been shown that carbonate apatite may be sintered, relatively little is known about its high temperature stability. Various atmospheres have been used in investigations into the thermal stability of hydroxyapatites and carbonate hydroxyapatites, including nitrogen, wet carbon dioxide air, water vapor and wet oxygen, but few of these studies were directly comparable. Previous work has shown that loss of carbonate from CHA at high temperature is time dependent, which suggests that rapid high temperature treatment may prevent carbonate loss during processing. This study investigated the effect of dry carbon dioxide, carbon dioxide containing 3% water, nitrogen and nitrogen containing 3% water on the phase composition of hydroxyapatite containing between 1.0 and 11.5 wt % carbonate rapidly heated to temperatures of between 700 and 1400 degrees C. Carbonate ion substitution was observed to decrease the temperature at which crystallisation occurred to a minimum of 700 degrees C for 11.8 wt % carbonate apatite heated in wet atmospheres. Atmosphere was found to appreciably affect the crystallization temperature and phase transformations of carbonate apatite containing 7.8 wt % carbonate. In wet and dry carbon dioxide atmospheres, crystallisation began in this material at 1100 and 900 degrees C, betaTCP was formed at 1500 and 1300 degrees C respectively. The high temperature decomposition of carbonate hydroxyapatite would appear to depend on the composition of the apatite and the atmosphere in which it is heated. PMID:15348582

  9. Study of phase decomposition and coarsening of ?? precipitates in Ni-12 at.% Ti alloy

    SciTech Connect

    Garay-Reyes, C.G.; Hernández-Santiago, F.; Cayetano-Castro, N.; López-Hirata, V.M.; García-Rocha, J.; Hernández-Rivera, J.L.; Dorantes-Rosales, H.J.; Cruz-Rivera, J.J.

    2013-09-15

    The early stages of phase decomposition, morphological evolution of precipitates, coarsening kinetics of ?? precipitates and micro-hardness in Ni-12 at.% Ti alloy are studied by transmission electron microscopy (TEM) and Vickers hardness tests (VHN). Disk-shaped specimens are solution treated at 1473 K (1200 °C) and aged at 823, 923 and 1023 K (550, 650 and 750 °C) during several periods of time. TEM results show that a conditional spinodal of order occurs at the beginning of the phase decomposition and exhibit the following decomposition sequence and morphological evolution of precipitates: ?{sub sss} ? ?? irregular–cuboidal + ?{sub s} ? ?? cuboidal–parallelepiped + ? ? ? plates + ?. In general during the coarsening of ?? precipitates, the experimental coarsening kinetics do not fit well to the LSW or TIDC (n = 2.281) theoretical models, however the activation energies determined using the TIDC and LSW theories (262.846 and 283.6075 kJ mol{sup ?1}, respectively) are consistent with previously reported values. The highest hardness obtained at 823, 923 and 1023 K (550, 650 and 750 °C) is associated with the presence of ?? precipitates. - Highlights: • It was studied the conditional spinodal during early stages of phase decomposition. • It was obtained decomposition sequence and morphological evolution of precipitates. • It was experimentally evaluated the coarsening kinetics of ?? precipitates. • The maximum hardness is associated with the ?? precipitates.

  10. The Role of Endophytic Fungal Individuals and Communities in the Decomposition of Pinus massoniana Needle Litter

    PubMed Central

    Yuan, Zhilin; Chen, Lianqing

    2014-01-01

    The role of fungal endophytes (FEs) as “pioneer” decomposers has recently been recognized; however, the extent to which FEs contribute to litter loss is less well understood. The genetic and enzymatic bases of FE-mediated decomposition have also rarely been addressed. The effects of populations and individuals (with an emphasis on two dominant Lophodermium taxa) of FEs on needle-litter decomposition were assessed for Pinus massoniana, a ubiquitous pine in southern China. Data from in vivo (microcosm) experiments indicated that the percentage of litter-mass loss triggered by FEs was linearly correlated with incubation time and approached 60% after seven months. In vitro decomposition tests also confirmed that endophytic Lophodermium isolates caused 14–22% mass loss within two months. Qualitative analysis of exoenzymes (cellulase and laccase, important for lignocellulose degradation) revealed that almost all of the Lophodermium isolates showed moderate or strong positive reactions. Furthermore, partial sequences of ?-glucosidase (glycoside hydrolase family 3, GH3), laccase, and cellobiohydrolase (GH7) genes were amplified from Lophodermium isolates as “functional markers” to evaluate their potential for lignocellulolytic activity. Three different genes were detected, suggesting a flexible and delicate decomposition system rich in FEs. Our work highlights the possibility that the saprophytism and endophytism of FEs may be prerequisites to initiating rapid decomposition and thus may be key in Fes’ contribution to litter decomposition, at least in the early stage. Potential indicators of the presence of core fungal decomposers are also briefly discussed. PMID:25157631

  11. STELLAR POPULATIONS OF LYMAN BREAK GALAXIES AT z {approx_equal} 1-3 IN THE HST/WFC3 EARLY RELEASE SCIENCE OBSERVATIONS

    SciTech Connect

    Hathi, N. P.; McCarthy, P. J.; Cohen, S. H.; Windhorst, R. A.; Rutkowski, M. J.; Ryan, R. E. Jr.; Koekemoer, A. M.; Bond, H. E.; Finkelstein, S. L.; Yan, H.; O'Connell, R. W.; Straughn, A. N.; Kimble, R. A.; Balick, B.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; and others

    2013-03-10

    We analyze the spectral energy distributions (SEDs) of Lyman break galaxies (LBGs) at z {approx_equal} 1-3 selected using the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) UVIS channel filters. These HST/WFC3 observations cover about 50 arcmin{sup 2} in the GOODS-South field as a part of the WFC3 Early Release Science program. These LBGs at z {approx_equal} 1-3 are selected using dropout selection criteria similar to high-redshift LBGs. The deep multi-band photometry in this field is used to identify best-fit SED models, from which we infer the following results: (1) the photometric redshift estimate of these dropout-selected LBGs is accurate to within few percent; (2) the UV spectral slope {beta} is redder than at high redshift (z > 3), where LBGs are less dusty; (3) on average, LBGs at z {approx_equal} 1-3 are massive, dustier, and more highly star forming, compared to LBGs at higher redshifts with similar luminosities (0.1L* {approx}< L {approx}< 2.5L*), though their median values are similar within 1{sigma} uncertainties. This could imply that identical dropout selection technique, at all redshifts, finds physically similar galaxies; and (4) the stellar masses of these LBGs are directly proportional to their UV luminosities with a logarithmic slope of {approx}0.46, and star formation rates are proportional to their stellar masses with a logarithmic slope of {approx}0.90. These relations hold true-within luminosities probed in this study-for LBGs from z {approx_equal} 1.5 to 5. The star-forming galaxies selected using other color-based techniques show similar correlations at z {approx_equal} 2, but to avoid any selection biases, and for direct comparison with LBGs at z > 3, a true Lyman break selection at z {approx_equal} 2 is essential. The future HST UV surveys, both wider and deeper, covering a large luminosity range are important to better understand LBG properties and their evolution.

  12. Evaluating litter decomposition in earth system models with long-term litterbag experiments: an example using the Community Land Model version 4 (CLM4).

    PubMed

    Bonan, Gordon B; Hartman, Melannie D; Parton, William J; Wieder, William R

    2013-03-01

    Decomposition is a large term in the global carbon budget, but models of the earth system that simulate carbon cycle-climate feedbacks are largely untested with respect to litter decomposition. We tested the litter decomposition parameterization of the community land model version 4 (CLM4), the terrestrial component of the community earth system model, with data from the long-term intersite decomposition experiment team (LIDET). The LIDET dataset is a 10-year study of litter decomposition at multiple sites across North America and Central America. We performed 10-year litter decomposition simulations comparable with LIDET for 9 litter types and 20 sites in tundra, grassland, and boreal, conifer, deciduous, and tropical forest biomes using the LIDET-provided climatic decomposition index to constrain temperature and moisture effects on decomposition. We performed additional simulations with DAYCENT, a version of the CENTURY model, to ask how well an established ecosystem model matches the observations. The results show large discrepancy between the laboratory microcosm studies used to parameterize the CLM4 litter decomposition and the LIDET field study. Simulated carbon loss is more rapid than the observations across all sites, and nitrogen immobilization is biased high. Closer agreement with the observations requires much lower decomposition rates, obtained with the assumption that soil mineral nitrogen severely limits decomposition. DAYCENT better replicates the observations, for both carbon mass remaining and nitrogen, independent of nitrogen limitation. CLM4 has low soil carbon in global earth system simulations. These results suggest that this bias arises, in part, from too rapid litter decomposition. More broadly, the terrestrial biogeochemistry of earth system models must be critically tested with observations, and the consequences of particular model choices must be documented. Long-term litter decomposition experiments such as LIDET provide a real-world process-oriented benchmark to evaluate models. PMID:23504851

  13. Photoyield in the decomposition of nitrogen trichloride

    SciTech Connect

    Markevich, E.A.

    1986-12-01

    In order to explain the role of electronically excited chlorine molecules in the decomposition of nitrogen trichloride, an estimation was made of the concentration of the Cl/sub 2/ molecules forming. From the results obtained, it was concluded that electronically excited chlorine molecules do not show any substantial influence on the mechanism of decomposition of NCl/sub 3/.

  14. Morphological Decomposition in Arabic ASR Systems

    E-print Network

    de Gispert, Adrià

    Morphological Decomposition in Arabic ASR Systems F. Diehl, M.J.F. Gales, M. Tomalin, and P.K. Abstract In recent years, the use of morphological decomposition strategies for Arabic Automatic Speech by exploring the use of the `Morphological Analysis and Disambiguation for Arabic' (MADA) tools

  15. INTERACTIVE SIMULATION OF FIRE, BURN AND DECOMPOSITION

    E-print Network

    Keyser, John

    This work presents an approach to effectively integrate into one unified modular fire simulation framework- mentation can model fire, objects catching fire, burning objects, decomposition of burning objectsINTERACTIVE SIMULATION OF FIRE, BURN AND DECOMPOSITION A Dissertation by ZEKI MELEK Submitted

  16. Balanced 0 1 Matrices Part I: Decomposition

    E-print Network

    Cornuejols, Gerard P.

    Balanced 0 1 Matrices Part I: Decomposition Michele Conforti Gerard Cornuejols y Ajai Kapoor z and Kristina Vuskovic x revised September 2000 Abstract A 0 1 matrix is balanced if, in every square submatrix extends the decomposition of balanced 0 1 matrices obtained by Conforti, Cornuejols and Rao to the class

  17. Partial fraction decomposition of the Fermi function

    NASA Astrophysics Data System (ADS)

    Croy, Alexander; Saalmann, Ulf

    2009-08-01

    A partial fraction decomposition of the Fermi function resulting in a finite sum over simple poles is proposed. This allows for efficient calculations involving the Fermi function in various contexts of electronic-structure or electron-transport theories. The proposed decomposition converges in a well-defined region faster than exponential and is thus superior to the standard Matsubara expansion.

  18. Modular polynomial arithmetic in partial fraction decomposition

    NASA Technical Reports Server (NTRS)

    Abdali, S. K.; Caviness, B. F.; Pridor, A.

    1977-01-01

    Algorithms for general partial fraction decomposition are obtained by using modular polynomial arithmetic. An algorithm is presented to compute inverses modulo a power of a polynomial in terms of inverses modulo that polynomial. This algorithm is used to make an improvement in the Kung-Tong partial fraction decomposition algorithm.

  19. Gaussian Behavior in Generalized Zeckendorf Decompositions

    E-print Network

    Stoiciu, Mihai

    , generating functions, partial fraction expansion, central limit type theorems, far- differenceChapter 1 Gaussian Behavior in Generalized Zeckendorf Decompositions Steven J. Miller and Yinghui that is more combinatorial, and comment on general- izations to related decompositions and problems which have

  20. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Products 2 2010-01-01 2010-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products...Disposition of Diseased Rabbit Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  1. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Products 2 2014-01-01 2014-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products...Disposition of Diseased Rabbit Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  2. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Products 2 2012-01-01 2012-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products...Disposition of Diseased Rabbit Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  3. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Products 2 2011-01-01 2011-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products...Disposition of Diseased Rabbit Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  4. Sampling Stoichiometry: The Decomposition of Hydrogen Peroxide.

    ERIC Educational Resources Information Center

    Clift, Philip A.

    1992-01-01

    Describes a demonstration of the decomposition of hydrogen peroxide to provide an interesting, quantitative illustration of the stoichiometric relationship between the decomposition of hydrogen peroxide and the formation of oxygen gas. This 10-minute demonstration uses ordinary hydrogen peroxide and yeast that can be purchased in a supermarket.…

  5. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  6. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.93 Decomposition. Carcasses of poultry deleteriously affected by post mortem changes shall...

  7. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  8. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.93 Decomposition. Carcasses of poultry deleteriously affected by post mortem changes shall...

  9. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  10. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  11. 9 CFR 354.131 - Decomposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Decomposition. 354.131 Section 354.131 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Carcasses and Parts § 354.131 Decomposition. Carcasses of rabbits deleteriously affected by...

  12. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.93 Decomposition. Carcasses of poultry deleteriously affected by post mortem changes shall...

  13. Chinese Orthographic Decomposition and Logographic Structure

    ERIC Educational Resources Information Center

    Cheng, Chao-Ming; Lin, Shan-Yuan

    2013-01-01

    "Chinese orthographic decomposition" refers to a sense of uncertainty about the writing of a well-learned Chinese character following a prolonged inspection of the character. This study investigated the decomposition phenomenon in a test situation in which Chinese characters were repeatedly presented in a word context and assessed…

  14. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.93 Decomposition. Carcasses of poultry deleteriously affected by post mortem changes shall...

  15. 9 CFR 381.93 - Decomposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Decomposition. 381.93 Section 381.93 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.93 Decomposition. Carcasses of poultry deleteriously affected by post mortem changes shall...

  16. English and Turkish Pupils' Understanding of Decomposition

    ERIC Educational Resources Information Center

    Cetin, Gulcan

    2007-01-01

    This study aimed to describe seventh grade English and Turkish students' levels of understanding of decomposition. Data were analyzed descriptively from the students' written responses to four diagnostic questions about decomposition. Results revealed that the English students had considerably higher sound understanding and lower no understanding…

  17. High temperature phase decomposition in Ti{sub x}Zr{sub y}Al{sub z}N

    SciTech Connect

    Lind, Hans; Pilemalm, Robert; Rogström, Lina; Tasnadi, Ferenc; Ghafoor, Naureen; Forsén, Rikard; Odén, Magnus; Johnson, Lars J. S.; Johansson-Jöesaar, Mats P.; Abrikosov, Igor A.

    2014-12-15

    Through a combination of theoretical and experimental observations we study the high temperature decomposition behavior of c-(Ti{sub x}Zr{sub y}Al{sub z}N) alloys. We show that for most concentrations the high formation energy of (ZrAl)N causes a strong tendency for spinodal decomposition between ZrN and AlN while other decompositions tendencies are suppressed. In addition we observe that entropic effects due to configurational disorder favor a formation of a stable Zr-rich (TiZr)N phase with increasing temperature. Our calculations also predict that at high temperatures a Zr rich (TiZrAl)N disordered phase should become more resistant against the spinodal decomposition despite its high and positive formation energy due to the specific topology of the free energy surface at the relevant concentrations. Our experimental observations confirm this prediction by showing strong tendency towards decomposition in a Zr-poor sample while a Zr-rich alloy shows a greatly reduced decomposition rate, which is mostly attributable to binodal decomposition processes. This result highlights the importance of considering the second derivative of the free energy, in addition to its absolute value in predicting decomposition trends of thermodynamically unstable alloys.

  18. Decomposition patterns in terrestrial and intertidal habitats on Oahu Island and Coconut Island, Hawaii.

    PubMed

    Davis, J B; Goff, M L

    2000-07-01

    Decomposition studies were conducted at two sites on the Island of Oahu, Hawaii, to compare patterns of decomposition and arthropod invasion in intertidal and adjacent terrestrial habitats. The animal model used was the domestic pig. One site was on Coconut Island in Kaneohe Bay on the northeast side of Oahu, and the second was conducted in an anchialine pool located at Barber's Point Naval Air Station on the southwest shore of Oahu. At both sites, the terrestrial animal decomposed in a manner similar to what has been observed in previous studies in terrestrial habitats on the island of Oahu. Rate of biomass depletion was slower in both intertidal studies, and decomposition was primarily due to tide and wave activity and bacterial decomposition. No permanent colonization of carcasses by insects was seen for the intertidal carcass at Coconut Island. At the anchialine pool at Barber's Point Naval Air Station, Diptera larvae were responsible for biomass removal until the carcass was reduced below the water line and, from that point on, bacterial action was the means of decomposition. Marine and terrestrial scavengers were present at both sites although their impact on decomposition was negligible. Five stages of decomposition were recognized for the intertidal sites: fresh, buoyant/floating, deterioration/disintegration, buoyant remains, and scattered skeletal. PMID:10914580

  19. Structure, Growth, and Decomposition of Laminated Algal-Bacterial Mats in Alkaline Hot Springs

    PubMed Central

    Doemel, W. N.; Brock, Thomas D.

    1977-01-01

    Laminated mats of unique character in siliceous alkaline hot springs of Yellowstone Park are formed predominantly by two organisms, a unicellular blue-green alga, Synechococcus lividus, and a filamentous, gliding, photosynthetic bacterium, Chloroflexus aurantiacus. The mats can be divided approximately into two major zones: an upper, aerobic zone in which sufficient light penetrates for net photosynthesis, and a lower, anaerobic zone, where photosynthesis does not occur and decomposition is the dominant process. Growth of the mat was followed by marking the mat surface with silicon carbide particles. The motile Chloroflexus migrates vertically at night, due to positive aerotaxis, responding to reduced O2 levels induced by dark respiration. The growth rates of mats were estimated at about 50 ?m/day. Observations of a single mat at Octopus Spring showed that despite the rapid growth rate, the thickness of the mat remained essentially constant, and silicon carbide layers placed on the surface gradually moved to the bottom of the mat, showing that decomposition was taking place. There was a rapid initial rate of decomposition, with an apparent half-time of about 1 month, followed by a slower period of decomposition with a half-time of about 12 months. Within a year, complete decomposition of a mat of about 2-cm thickness can occur. Also, the region in which decomposition occurs is strictly anaerobic, showing that complete decomposition of organic matter from these organisms can occur in the absence of O2. Images PMID:16345254

  20. TE/TM decomposition of electromagnetic sources

    NASA Technical Reports Server (NTRS)

    Lindell, Ismo V.

    1988-01-01

    Three methods are given by which bounded EM sources can be decomposed into two parts radiating transverse electric (TE) and transverse magnetic (TM) fields with respect to a given constant direction in space. The theory applies source equivalence and nonradiating source concepts, which lead to decomposition methods based on a recursive formula or two differential equations for the determination of the TE and TM components of the original source. Decompositions for a dipole in terms of point, line, and plane sources are studied in detail. The planar decomposition is seen to match to an earlier result given by Clemmow (1963). As an application of the point decomposition method, it is demonstrated that the general exact image expression for the Sommerfeld half-space problem, previously derived through heuristic reasoning, can be more straightforwardly obtained through the present decomposition method.

  1. Multilinear operators for higher-order decompositions.

    SciTech Connect

    Kolda, Tamara Gibson

    2006-04-01

    We propose two new multilinear operators for expressing the matrix compositions that are needed in the Tucker and PARAFAC (CANDECOMP) decompositions. The first operator, which we call the Tucker operator, is shorthand for performing an n-mode matrix multiplication for every mode of a given tensor and can be employed to concisely express the Tucker decomposition. The second operator, which we call the Kruskal operator, is shorthand for the sum of the outer-products of the columns of N matrices and allows a divorce from a matricized representation and a very concise expression of the PARAFAC decomposition. We explore the properties of the Tucker and Kruskal operators independently of the related decompositions. Additionally, we provide a review of the matrix and tensor operations that are frequently used in the context of tensor decompositions.

  2. Management intensity alters decomposition via biological pathways

    USGS Publications Warehouse

    Wickings, Kyle; Grandy, A. Stuart; Reed, Sasha; Cleveland, Cory

    2011-01-01

    Current conceptual models predict that changes in plant litter chemistry during decomposition are primarily regulated by both initial litter chemistry and the stage-or extent-of mass loss. Far less is known about how variations in decomposer community structure (e.g., resulting from different ecosystem management types) could influence litter chemistry during decomposition. Given the recent agricultural intensification occurring globally and the importance of litter chemistry in regulating soil organic matter storage, our objectives were to determine the potential effects of agricultural management on plant litter chemistry and decomposition rates, and to investigate possible links between ecosystem management, litter chemistry and decomposition, and decomposer community composition and activity. We measured decomposition rates, changes in litter chemistry, extracellular enzyme activity, microarthropod communities, and bacterial versus fungal relative abundance in replicated conventional-till, no-till, and old field agricultural sites for both corn and grass litter. After one growing season, litter decomposition under conventional-till was 20% greater than in old field communities. However, decomposition rates in no-till were not significantly different from those in old field or conventional-till sites. After decomposition, grass residue in both conventional- and no-till systems was enriched in total polysaccharides relative to initial litter, while grass litter decomposed in old fields was enriched in nitrogen-bearing compounds and lipids. These differences corresponded with differences in decomposer communities, which also exhibited strong responses to both litter and management type. Overall, our results indicate that agricultural intensification can increase litter decomposition rates, alter decomposer communities, and influence litter chemistry in ways that could have important and long-term effects on soil organic matter dynamics. We suggest that future efforts to more accurately predict soil carbon dynamics under different management regimes may need to explicitly consider how changes in litter chemistry during decomposition are influenced by the specific metabolic capabilities of the extant decomposer communities.

  3. Engaging Practitioners in Program Evaluation: A Preliminary Report of Perceptions and Observations of Practitioner-Caregiver Partnerships in Early Intervention. A Program Evaluation Report

    ERIC Educational Resources Information Center

    Bainter, Sue; Marvin, Chris

    2006-01-01

    Background: Many early intervention teams are shifting their service delivery for children with disabilities from a child-focused model to one that focuses on strengthening the competence and confidence of the child's caregivers (parents, childcare providers, preschool teachers). The use of coaching strategies in a primary coach model of service…

  4. DEVELOPMENT OF A NOVEL CATALYST FOR NO DECOMPOSITION

    SciTech Connect

    Ates Akyurtlu; Jale F. Akyurtlu

    2004-05-01

    Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NO{sub x} emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N{sub 2} will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation leads one to believe that the Pt/SnO{sub 2} catalysts may have a potential as NO decomposition catalysts in the presence of oxygen. This prediction is also supported by some preliminary data obtained for NO decomposition on a Pt/SnO{sub 2} catalyst in the PI's laboratory. The main objective of the proposed research is the evaluation of the Pt/SnO{sub 2} catalysts for the decomposition of NO in simulated power plant stack gases with particular attention to the resistance to deactivation by O{sub 2}, CO{sub 2}, and elevated temperatures. Therefore, it is proposed to perform temperature programmed desorption (TPD) and temperature programmed reaction (TPRx) studies on Pt/SnO{sub 2} catalysts having different noble metal concentrations and pretreated under different conditions. It is also proposed to perform NO decomposition tests in a laboratory-size packed-bed reactor to obtain long-term deactivation data. In the current reporting period first the GC-MS system was calibrated. Then the TPD runs for the 15% Pt/SnO{sub 2} catalyst after treatment with NO and subsequent treatments with NO and O{sub 2} were done. For these runs the catalyst was pretreated with dry helium for 2 hours at 40 C.

  5. Impact of nitrogen and phosphorus on [C]lignocellulose decomposition by stream wood microflora.

    PubMed

    Aumen, N G; Bottomley, P J; Gregory, S V

    1985-05-01

    Nutritional and physical factors affecting the decomposition of [C]lignocellulose prepared from Douglas fir (Pseudotsuga menziesii) were examined by incubating the labeled substrate with homogenized surface wood scrapings obtained from a Douglas fir log in a Pacific Northwest stream. Incubations were conducted in distilled water, in stream water collected from four different sources, or in a defined mineral salts solution with or without supplemental N (KNO(3)). Decomposition rates of [C]lignocellulose, as measured by CO(2) evolution, were greater in each of the four filter-sterilized sources of stream water than in distilled water alone. Decomposition experiments conducted in stream water media with the addition of defined mineral salts demonstrated that [C]cellulose decomposition was stimulated 50% by the addition of either KNO(3) or KH(2)PO(4)/K(2)HPO(4) and further enhanced (167%) by a combination of both. In contrast, [C]lignin decomposition was stimulated (65%) only by the addition of both N and P. Decomposition of [C]lignocellulose was greatest when supplemental KNO(3) was supplied in concentrations of at least 10.0 mg of N liter but not increased further by higher concentrations. The decomposition of [C]lignocellulose increased as the incubation temperature was raised and NO(3)-N supplementation further increased these rates between three-and sevenfold over the range of temperatures examined (5 to 22 degrees C). Accumulation of NH(4) (2 to 4 mg of N liter) was always observed in culture filtrates of incubations which had been supplemented with KNO(3), the quantity being independent of NO(3) concentrations >/= 10 mg of N liter. The role of supplemental NO(3) in the decomposition of [C]lignocellulose is discussed in relation to wood decomposition and the low concentrations of N found in stream ecosystems of the Pacific Northwest. PMID:16346784

  6. Decomposition reactions in RDX at elevated temperatures and pressures

    NASA Astrophysics Data System (ADS)

    Schweigert, Igor

    2015-03-01

    Mechanisms and rates of elementary reactions controlling condensed-phase decomposition of RDX under elevated temperatures (up to 2000 K) and pressures (up to a few GPa) are not known. Global decomposition kinetics in RDX below 700 K has been measured; however, the observed global pathways result from complex manifolds of elementary reactions and are likely to be altered by elevated temperatures. Elevated pressures can further affect the condensed-phase kinetics and compete with elevated temperatures in promoting some elementary reactions and suppressing others. This presentation will describe density functional theory (DFT) based molecular dynamics simulations of crystalline and molten RDX aimed to delineate the effects of elevated temperatures and pressures on the mechanism of initial dissociation and the resulting secondary reactions. This work was supported by the Naval Research Laboratory, by the Office of Naval Research, and by the DOD High Performance Computing Modernization Program Software Application Institute for Multiscale Reactive Modeling of Insensitive Munitions.

  7. Decomposition method for block-tridiagonal matrix systems

    E-print Network

    Belov, P A; Yakovlev, S L

    2015-01-01

    The decomposition method which makes the parallel solution of the block-tridiagonal matrix systems possible is presented. The performance of the method is analytically estimated based on the number of elementary multiplicative operations for its parallel and serial parts. The computational speedup with respect to the conventional sequential Thomas algorithm is assessed for various types of the application of the method. It is observed that the maximum of the analytical speedup for a given number of blocks on the diagonal is achieved at some finite number of parallel processors. The values of the parameters required to reach the maximum computational speedup are obtained. The benchmark calculations show a good agreement of analytical estimations of the computational speedup and practically achieved results. The application of the method is illustrated by employing the decomposition method to the matrix system originated from a boundary value problem for the two-dimensional integro-differential Faddeev equation...

  8. An investigation of the mechanism of the base-induced decomposition of hydrogen peroxide

    SciTech Connect

    Lin, Y.K.; Huang, C.R.

    1995-12-31

    Hydrogen peroxide is a key component in Advanced Oxidation Processes (AOPs). The decomposition of hydrogen peroxide at different pH conditions has been studied and some of interesting results were observed. When the pH value of hydrogen peroxide solution is less than 9, the rate of decomposition is independent of pH. In the pH range of 9-12.6, the decomposition rate increases and goes through a maximum value then suddenly decreases with respect to pH. A reaction kinetic model with three rate constants in the form of beta probability function was used to describe experimental data of the decomposition of hydrogen peroxide at various pH values.

  9. Sequence of Tissue Responses in the Early Stages of Experimental Allergic Encephalomyelitis (EAE): Immunohistochemical, Light Microscopic, and Ultrastructural Observations in the Spinal Cord

    NASA Technical Reports Server (NTRS)

    DAmelio, Fernando E.; Smith, Marion E.; Eng, Lawrence F.

    1990-01-01

    Experimental allergic encephalomyelitis (EAE) was induced in adult Lewis rats with purified guinea pig CNS myelin and Freund's adjuvant. As soon as the very earliest clinical signs appeared the animals were perfused with fixatives and the spinal cord analyzed by electron microscopy, silver methods, and immunocytochemistry. Our findings suggest that in the early stages of EAE a sequence of events can be traced, although these events frequently overlap. The earliest morphological change appears to be astrocytic edema in both the cell body and processes. Increased amounts of glycogen particles and dispersion of glial filaments are prominent. These changes seem to occur just prior to the time when inflammatory cells begin to penetrate the capillary walls. Invasion of the neuropil mainly by macrophages and lymphocytes closely follows. Both macrophages and microglia seem to participate in phagocytosis of oligodendrocytes and myelin. Demyelination, however, is not a prominent feature at this early stage.

  10. Insights from letter position dyslexia on morphological decomposition in reading

    PubMed Central

    Friedmann, Naama; Gvion, Aviah; Nisim, Roni

    2015-01-01

    We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading “cloud” for “could”). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word is re-analyzed as two separate words. In this reanalysis, letter positions in each constituent word are encoded separately, and hence the exterior letters of the root are treated as exterior and do not migrate. PMID:26190985

  11. Insights from letter position dyslexia on morphological decomposition in reading.

    PubMed

    Friedmann, Naama; Gvion, Aviah; Nisim, Roni

    2015-01-01

    We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading "cloud" for "could"). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word is re-analyzed as two separate words. In this reanalysis, letter positions in each constituent word are encoded separately, and hence the exterior letters of the root are treated as exterior and do not migrate. PMID:26190985

  12. Sustaining effect of soil warming on organic matter decomposition

    NASA Astrophysics Data System (ADS)

    Hou, Ruixing; Ouyang, Zhu; Dorodnikov, Maxim; Wilson, Glenn; Kuzyakov, Yakov

    2015-04-01

    Global warming affects various parts of carbon (C) cycle including acceleration of soil organic matter (SOM) decomposition with strong feedback to atmospheric CO2 concentration. Despite many soil warming studies showed changes of microbial community structure, only very few were focused on sustainability of soil warming on microbial activity associated with SOM decomposition. Two alternative hypotheses: 1) acclimation because of substrate exhaustion and 2) sustaining increase of microbial activity with accelerated decomposition of recalcitrant SOM pools were never proven under long term field conditions. This is especially important in the nowadays introduced no-till crop systems leading to redistribution of organic C at the soil surface, which is much susceptible to warming effects than the rest of the profile. We incubated soil samples from a four-year warming experiment with tillage (T) and no-tillage (NT) practices under three temperatures: 15, 21, and 27 °C, and related the evolved total CO2 efflux to changes of organic C pools. Warmed soils released significantly more CO2 than the control treatment (no warming) at each incubation temperature, and the largest differences were observed under 15 °C (26% increase). The difference in CO2 efflux from NT to T increase with temperature showing high vulnerability of C stored in NT to soil warming. The Q10 value reflecting the sensitivity of SOM decomposition to warming was lower for warmed than non-warmed soil indicating better acclimation of microbes or lower C availability during long term warming. The activity of three extracellular enzymes: ?-glucosidase, chitinase, sulphatase, reflecting the response of C, N and S cycles to warming, were significantly higher under warming and especially under NT compared to two other respective treatments. The CO2 released during 2 months of incubation consisted of 85% from recalcitrant SOM and the remaining 15% from microbial biomass and extractable organic C based on the decrease of respective OM pools during incubation. The dominance of CO2 from recalcitrant SOM was especially pronounced in NT. We conclude that the accelerated decomposition of recalcitrant SOM due to stimulation of microorganisms by warming is sustainable. Consequently, predictions of redistribution or even accumulation of C in the topsoil of no-till should be taken with high caution, as global warming could potentially sustain high rates of decomposition.

  13. Early Astronomy

    NASA Astrophysics Data System (ADS)

    Thurston, Hugh

    The earliest investigations that can be called scientific are concerned with the sky: they are the beginnings of astronomy. Many early civilizations produced astronomical texts, and several cultures that left no written records left monuments and artifacts-ranging from rock paintings to Stonehenge-that show a clear interest in astronomy. Civilizations in China, Mesopotamia, India and Greece had highly developed astronomies, and the astronomy of the Mayas was by no means negligible. Greek astronomy, as developed by the medieval Arab philosophers, evolved into the astronomy of Copernicus. This displaced the earth from the central stationary position that almost all earlier astronomies had assumed. Soon thereafter, in the first decades of the seventeenth century, Kepler found the true shape of the planetary orbits and Galileo introduced the telescope for astronomical observations.

  14. Experimental Shock Decomposition of Siderite to Magnetite

    NASA Technical Reports Server (NTRS)

    Bell, M. S.; Golden, D. C.; Zolensky, M. E.

    2005-01-01

    The debate about fossil life on Mars includes the origin of magnetites of specific sizes and habits in the siderite-rich portions of the carbonate spheres in ALH 84001 [1,2]. Specifically [2] were able to demonstrate that inorganic synthesis of these compositionally zoned spheres from aqueous solutions of variable ion-concentrations is possible. They further demonstrated the formation of magnetite from siderite upon heating at 550 C under a Mars-like CO2-rich atmosphere according to 3FeCO3 = Fe3O4 + 2CO2 + CO [3] and they postulated that the carbonates in ALH 84001 were heated to these temperatures by some shock event. The average shock pressure for ALH 84001, substantially based on the refractive index of diaplectic feldspar glasses [3,4,5] is some 35-40 GPa and associated temperatures are some 300-400 C [4]. However, some of the feldspar is melted [5], requiring local deviations from this average as high as 45-50 GPa. Indeed, [5] observes the carbonates in ALH 84001 to be melted locally, requiring pressures in excess of 60 GPa and temperatures > 600 C. Combining these shock studies with the above inorganic synthesis of zoned carbonates it seems possible to produce the ALH 84001 magnetites by the shock-induced decomposition of siderite.

  15. Comparison of the Decomposition VOC Profile during Winter and Summer in a Moist, Mid-Latitude (Cfb) Climate

    PubMed Central

    Forbes, Shari L.; Perrault, Katelynn A.; Stefanuto, Pierre-Hugues; Nizio, Katie D.; Focant, Jean-François

    2014-01-01

    The investigation of volatile organic compounds (VOCs) associated with decomposition is an emerging field in forensic taphonomy due to their importance in locating human remains using biological detectors such as insects and canines. A consistent decomposition VOC profile has not yet been elucidated due to the intrinsic impact of the environment on the decomposition process in different climatic zones. The study of decomposition VOCs has typically occurred during the warmer months to enable chemical profiling of all decomposition stages. The present study investigated the decomposition VOC profile in air during both warmer and cooler months in a moist, mid-latitude (Cfb) climate as decomposition occurs year-round in this environment. Pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their VOC profile was monitored during the winter and summer months. Corresponding control sites were also monitored to determine the natural VOC profile of the surrounding soil and vegetation. VOC samples were collected onto sorbent tubes and analyzed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC-TOFMS). The summer months were characterized by higher temperatures and solar radiation, greater rainfall accumulation, and comparable humidity when compared to the winter months. The rate of decomposition was faster and the number and abundance of VOCs was proportionally higher in summer. However, a similar trend was observed in winter and summer demonstrating a rapid increase in VOC abundance during active decay with a second increase in abundance occurring later in the decomposition process. Sulfur-containing compounds, alcohols and ketones represented the most abundant classes of compounds in both seasons, although almost all 10 compound classes identified contributed to discriminating the stages of decomposition throughout both seasons. The advantages of GC×GC-TOFMS were demonstrated for detecting and identifying trace levels of VOCs, particularly ethers, which are rarely reported as decomposition VOCs. PMID:25412504

  16. Under-saturation of quarks at early stages of relativistic nuclear collisions: The hot glue initial scenario and its observable signatures

    NASA Astrophysics Data System (ADS)

    Stöcker, H.; Beitel, M.; Biró, T. S.; Csernai, L. P.; Gallmeister, K.; Gorenstein, M. I.; Greiner, C.; Mishustin, I. N.; Panero, M.; Raha, S.; Satarov, L. M.; Schramm, S.; Senzel, F.; Sinha, B.; Steinheimer, J.; Struckmeier, J.; Vovchenko, V.; Xu, Z.; Zhou, K.; Zhuang, P.

    2015-11-01

    The early stage of high multiplicity nuclear collisions is represented by a nearly quarkless, hot, deconfined pure gluon plasma. These new scenario should be characterized by a suppression of high p_T photons and dileptons as well as by reduced baryon to meson ratios. We present the numerical results for central Pb+Pb collisions at the LHC energies by using the ideal Bjorken hydrodynamics with time-dependent quark fugacity. It is shown that about 25 % of final total entropy is generated during the hydrodynamic evolution of chemically undersaturated quark-gluon plasma.

  17. Photometric Decomposition of Barred Galaxies

    E-print Network

    A. S. Reese; T. B. Williams; J. A. Sellwood; Eric I. Barnes; Brian A. Powell

    2007-02-27

    We present a non-parametric method for decomposition of the light of disk galaxies into disk, bulge and bar components. We have developed and tested the method on a sample of 68 disk galaxies for which we have acquired I-band photometry. The separation of disk and bar light relies on the single assumption that the bar is a straight feature with a different ellipticity and position angle from that of the projected disk. We here present the basic method, but recognise that it can be significantly refined. We identify bars in only 47% of the more nearly face-on galaxies in our sample. The fraction of light in the bar has a broad range from 1.3% to 40% of the total galaxy light. If low-luminosity galaxies have more dominant halos, and if halos contribute to bar stability, the luminosity functions of barred and unbarred galaxies should differ markedly; while our sample is small, we find only a slight difference of low significance.

  18. Analysis of unknown words through morphological decomposition

    E-print Network

    van de Plassche, J; Black, Alan W

    1991-01-01

    This paper describes a method of analysing words through morphological decomposition when the lexicon is incomplete. The method is used within a text-to-speech system to help generate pronunciations of unknown words. The ...

  19. Prelexical Decomposition of Compound and Pseudocompound Words

    E-print Network

    Diener, Un So Park

    2007-12-12

    recognition, although such effects should disappear quickly, as the decomposition does not help in the identification of the whole word. Experiment 1 assessed priming effects of compound words and pseudocompound words on their constituents at SOAs of 150ms...

  20. Interactive simulation of fire, burn and decomposition 

    E-print Network

    Melek, Zeki

    2009-05-15

    This work presents an approach to effectively integrate into one unified modular fire simulation framework the major processes related to fire, namely: a burning process, chemical combustion, heat distribution, decomposition and deformation...

  1. Polynomial decomposition algorithms in signal processing

    E-print Network

    Su, Guolong, S.M. Massachusetts Institute of Technology

    2013-01-01

    Polynomial decomposition has attracted considerable attention in computational mathematics. In general, the field identifies polynomials f(x) and g(x) such that their composition f(g(x)) equals or approximates a given ...

  2. Unimolecular decomposition of methyltrichlorosilane: RRKM calculations

    SciTech Connect

    Osterheld, T.H.; Allendorf, M.D.; Melius, C.F.

    1993-06-01

    Based on reaction thermochemistry and estimates of Arrhenius A-factors, it is expected that Si-C bond cleavage, C-H bond cleavage, and HCl elimination will be the primary channels for the unimolecular decomposition of methyltrichlorosilane. Using RRKM theory, we calculated rate constants for these three reactions. The calculations support the conclusion that these three reactions are the major decomposition pathways. Rate constants for each reaction were calculated in the high-pressure limit (800--1500 K) and in the falloff regime (1300--1500 K) for bath gases of both helium and hydrogen. These calculations thus provide branching fractions as well as decomposition rates. We also calculated bimolecular rate constants for the overall decomposition in the low-pressure limit. Interesting and surprising kinetic behavior of this system and the individual reactions is discussed. The reactivity of this chlorinated organosilane is compared to that of other organosilanes.

  3. [Litter decomposition of dominant plant species in successional stages in mid-subtropical zone].

    PubMed

    Song, Xin-zhang; Ma, Jiang Hong; Yu, Shu-quan; Ma, Yuan-dan; Zhou, Guo-mo; Dou, Rong-peng; Guo, Pei-pei

    2009-03-01

    The litters of seven tree species representing the dominant plant species in three main successional stages in subtropical China, i.e., Pinus massoniana in early successional forests, Schima superba and Cinnamanun camphora in transitional forests, and Castanopsis eyeri, Cyclobalanopsis gracilis, Cyclobalanopsis glauca, and Michelia chapensis in late successional forests, were collected, and their decomposition rates were measured with litterbags. The results showed that M. chapensls and C. gracilis had the highest litter decomposition rate (k = 1.12 and 0.89, respectively), followed by C. camphora and S. superba (k = 0.61 and 0.55, respectively), and P. massoniana (k = 0.51), indicating that there was a trend of litter decomposition rate being increased with succession stage. Litter decomposition rate had significant correlations with the litter' s initial P, N, and lignin contents, lignin/N ratio (P < 0.01), and C/N ratio (P < 0.05), suggesting that the initial P, N, and lignin contents and lignin/N ratio of leaf litter could be the good indictors of litter decomposition rate. PMID:19637588

  4. Nitrogen addition changes grassland soil organic matter decomposition

    E-print Network

    Minnesota, University of

    Nitrogen addition changes grassland soil organic matter decomposition Charlotte E. Riggs . Sarah E decomposition, as well as the pools that have been stabilized against microbial decomposition via aggregate the decomposi- tion of SOM, as well as stabilizing SOM against microbial decomposition in aggregate

  5. Hydrogen Sulfide Decomposition in Pulsed Corona Discharge Reactors

    NASA Astrophysics Data System (ADS)

    John, S.; Zhao, G. B.; Zhang, J. J.; Hamann, J. C.; Muknahallipatna, S. S.; Legowski, S.; Ackerman, J. F.; Argyle, M. D.

    2008-10-01

    Hydrogen sulfide (H2S) decomposition was carried out in each of four balance gases (Ar, He, N2 and H2) in a wire-in-tube pulsed corona discharge reactor. H2S conversion rates and H2S decomposition energy efficiencies depend on the balance gas and H2S concentrations. H2S conversion in monatomic balance gases, like Ar and He, is more efficient than in diatomic balance gases like N2 and H2. Low pulse forming capacitance, low charge voltage, and high pulse frequency operation produces the highest energy efficiency for H2S conversion at constant power. H2S conversion is more efficient in Ar-N2 gas mixture than in Ar or N2. These results can be explained by corona discharge observations, the electron attachment reactions of H2S and the proposed reaction mechanism of H2S dissociation. The results reveal the potential for energy efficient H2S decomposition in pulsed corona discharge reactors.

  6. Roaming radical kinetics in the decomposition of acetaldehyde.

    SciTech Connect

    Harding, L. B.; Georgievskii, Y.; Klippenstein, S. J.; Chemical Sciences and Engineering Division

    2010-01-01

    A novel theoretical framework for predicting the branching between roaming and bond fission channels in molecular dissociations is described and applied to the decomposition of acetaldehyde. This reduced dimensional trajectory (RDT) approach, which is motivated by the long-range nature of the roaming, bond fission, and abstraction dynamical bottlenecks, involves the propagation of rigid-body trajectories on an analytic potential energy surface. The analytic potential is obtained from fits to large-scale multireference ab initio electronic structure calculations. The final potential includes one-dimensional corrections from higher-level electronic structure calculations and for the effect of conserved mode variations along both the addition and abstraction paths. The corrections along the abstraction path play a significant role in the predicted branching. Master equation simulations are used to transform the microcanonical branching ratios obtained from the RDT simulations to the temperature- and pressure-dependent branching ratios observed in thermal decomposition experiments. For completeness, a transition-state theory treatment of the contributions of the tight transition states for the molecular channels is included in the theoretical analyses. The theoretically predicted branching between molecules and radicals in the thermal decomposition of acetaldehyde is in reasonable agreement with the corresponding shock tube measurement described in the companion paper. The prediction for the ratio of the tight to roaming contributions to the molecular channel also agrees well with results extracted from recent experimental and experimental/theoretical photodissociation studies.

  7. Critical analysis of nitramine decomposition data: Activation energies and frequency factors for HMX and RDX decomposition

    NASA Technical Reports Server (NTRS)

    Schroeder, M. A.

    1980-01-01

    A summary of a literature review on thermal decomposition of HMX and RDX is presented. The decomposition apparently fits first order kinetics. Recommended values for Arrhenius parameters for HMX and RDX decomposition in the gaseous and liquid phases and for decomposition of RDX in solution in TNT are given. The apparent importance of autocatalysis is pointed out, as are some possible complications that may be encountered in interpreting extending or extrapolating kinetic data for these compounds from measurements carried out below their melting points to the higher temperatures and pressure characteristic of combustion.

  8. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2014-05-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Owing to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult. In this study we compared changes in peat decomposition proxies in cores of two peat bogs (Königsmoor, KK; Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier transform infrared spectra absorption (FTIR) intensities, Rock Eva® oxygen and hydrogen indices, ?13C and ?15N isotopic signatures and UV-absorption (UV-ABS) of NaOH peat extracts. In order to explain parallels and discrepancies between these methods, one of the cores was additionally analysed by pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Pyrolysis-GC-MS data provide detailed information on a molecular level, which allows differentiation of both changes attributed to decomposition processes and changes in vegetation. Principal component analysis was used to identify and separate the effects of changes in vegetation pattern and decomposition processes because both may occur simultaneously upon changes in bog hydrology. Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling the process. All decomposition proxies except UV-ABS and ?15N isotopes show similar patterns in their records and reflect to different extents signals of decomposition. The molecular composition of the KK core reveals that these changes are mainly attributed to decomposition processes and to a lesser extent to changes in vegetation. Changes in the molecular composition indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation than polysaccharides or aliphatics, and presumably reflects changes in vegetation associated with changes in hydrology of the bogs. Significant correlations with polysaccharide and aliphatic pyrolysis products were found for C / N ratios, FTIR-band intensities and for hydrogen index values, supporting that these decomposition indices provide reasonable information. Correlations of polysaccharide and aliphatic pyrolysis products with oxygen index values and ?13C was weaker, assumingly indicating carboxylation of the peat during drier periods and enrichment of isotopically lighter peat components during decomposition, respectively. FTIR, C / N ratio, pyrolysis-GC-MS analyses and Rock Eval hydrogen indices appear to reflect mass loss and related changes in the molecular peat composition during mineralization best. Pyrolysis-GC-MS allows disentangling the decomposition processes and vegetation changes. UV-ABS measurements of alkaline peat extracts show only weak correlation with other decomposition proxies and pyrolysis results as they mainly reflect the formation of humic acids through humification and to a lesser extent mass loss during mineralization.

  9. Singular-value decomposition using quantum annealing

    NASA Astrophysics Data System (ADS)

    Hashizume, Yoichiro; Koizumi, Takashi; Akitaya, Kento; Nakajima, Takashi; Okamura, Soichiro; Suzuki, Masuo

    2015-08-01

    In the present study, we demonstrate how to perform, using quantum annealing, the singular value decomposition and the principal component analysis. Quantum annealing gives a way to find a ground state of a system, while the singular value decomposition requires the maximum eigenstate. The key idea is to transform the sign of the final Hamiltonian, and the maximum eigenstate is obtained by quantum annealing. Furthermore, the adiabatic time scale is obtained by the approximation focusing on the maximum eigenvalue.

  10. Domain decomposition for the SPN solver MINOS

    SciTech Connect

    Jamelot, Erell; Baudron, Anne-Marie; Lautard, Jean-Jacques

    2012-07-01

    In this article we present a domain decomposition method for the mixed SPN equations, discretized with Raviart-Thomas-Nedelec finite elements. This domain decomposition is based on the iterative Schwarz algorithm with Robin interface conditions to handle communications. After having described this method, we give details on how to optimize the convergence. Finally, we give some numerical results computed in a realistic 3D domain. The computations are done with the MINOS solver of the APOLLO3 (R) code. (authors)

  11. Moisture drives surface decomposition in thawing tundra

    NASA Astrophysics Data System (ADS)

    Hicks Pries, Caitlin E.; Schuur, E. A. G.; Vogel, Jason G.; Natali, Susan M.

    2013-07-01

    Permafrost thaw can affect decomposition rates by changing environmental conditions and litter quality. As permafrost thaws, soils warm and thermokarst (ground subsidence) features form, causing some areas to become wetter while other areas become drier. We used a common substrate to measure how permafrost thaw affects decomposition rates in the surface soil in a natural permafrost thaw gradient and a warming experiment in Healy, Alaska. Permafrost thaw also changes plant community composition. We decomposed 12 plant litters in a common garden to test how changing plant litter inputs would affect decomposition. We combined species' tissue-specific decomposition rates with species and tissue-level estimates of aboveground net primary productivity to calculate community-weighted decomposition constants at both the thaw gradient and warming experiment. Moisture, specifically growing season precipitation and water table depth, was the most significant driver of decomposition. At the gradient, an increase in growing season precipitation from 200 to 300 mm increased mass loss of the common substrate by 100%. At the warming experiment, a decrease in the depth to the water table from 30 to 15 cm increased mass loss by 100%. At the gradient, community-weighted decomposition was 21% faster in extensive than in minimal thaw, but was similar when moss production was included. Overall, the effect of climate change and permafrost thaw on surface soil decomposition are driven more by precipitation and soil environment than by changes to plant communities. Increasing soil moisture is thereby another mechanism by which permafrost thaw can become a positive feedback to climate change.

  12. High temperature decomposition of hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2005-01-01

    Nitric oxide (NO) is oxidized into nitrogen dioxide (NO2) by the high temperature decomposition of a hydrogen peroxide solution to produce the oxidative free radicals, hydroxyl and hydroperoxyl. The hydrogen peroxide solution is impinged upon a heated surface in a stream of nitric oxide where it decomposes to produce the oxidative free radicals. Because the decomposition of the hydrogen peroxide solution occurs within the stream of the nitric oxide, rapid gas-phase oxidation of nitric oxide into nitrogen dioxide occurs.

  13. A method for exponential operator decomposition

    E-print Network

    Seckin Sefi; Peter van Loock

    2011-10-18

    Exponential operator decompositions are an important tool in many fields of physics, for example, in quantum control, quantum computation, or condensed matter physics. In this work, we present a method for obtaining such decompositions, which is efficient in terms of the required number of operators. Compared to existing schemes, our more direct approach is general, in the sense that it can be applied to various kinds of operators including nested commutation operators, and it is systematic.

  14. High Temperature Decomposition of Hydrogen Peroxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2004-01-01

    Nitric oxide (NO) is oxidized into nitrogen dioxide (NO2) by the high temperature decomposition of a hydrogen peroxide solution to produce the oxidative free radicals, hydroxyl and hydropemxyl. The hydrogen peroxide solution is impinged upon a heated surface in a stream of nitric oxide where it decomposes to produce the oxidative free radicals. Because the decomposition of the hydrogen peroxide solution occurs within the stream of the nitric oxide, rapid gas-phase oxidation of nitric oxide into nitrogen dioxide occurs.

  15. Thermal decomposition and reconstitution of hydroxyapatite in air atmosphere.

    PubMed

    Liao, C J; Lin, F H; Chen, K S; Sun, J S

    1999-10-01

    In this paper, the decomposition and reconstruction behavior of hydroxyapatite (HAP) during heating and cooling in air atmosphere were studied. The commercial HAP were chosen and gradually heated to 1500 degrees C and cooled to room temperature by a program controlled SiC heated furnace. X-ray diffraction (XRD) and Fourier-transformed infrared (FTIR) analysis were used to investigate the change of crystalline phases and functional groups of HAP at different temperatures. Weight change of samples was recorded by thermogravimetric analysis (TGA) during heating and cooling. The results revealed that HAP gradually releases its OH- ions and transforms into OHAP in the temperature of 1000-1360 degrees C. Above 1360 degrees C, the OHAP would decompose into TTCP and alpha TCP phase. The OH- stretching bands of HAP could be traced by FTIR even at the temperature of 1350 degrees C which indicates HAP decomposition. HAP does not dehydrate completely before decomposition. We speculated that some oxyapatite (OAP) might be formed during dehydration with a great amount of OHAP still left in the system even up to the temperature of decomposition. In the temperature range of 1400-1500 degrees C, there was no significant difference in XRD patterns, only TTCP and alpha TCP crystalline phases were observed. When the HAP gradually cools from 1500 degrees C, a part of TTCP and alpha TCP would directly reconstruct into OAP around 1350 degrees C. OAP existed in the temperature range of 1350-1300 degrees C during cooling. When the temperature decreased to 1290 degrees C, a part of TTCP and alpha TCP reconstructed into OHAP by rehydration reaction and OAP were rehydrated into OHAP as well. At 1100 degrees C, the rest of TTCP and alpha TCP reconstitutes into HAP. As the temperature decreases, the OHAP is gradually rehydrated and reconstituted into HAP. PMID:10509191

  16. Temperature sensitivity of black carbon decomposition and oxidation.

    PubMed

    Nguyen, Binh Thanh; Lehmann, Johannes; Hockaday, William C; Joseph, Stephen; Masiello, Caroline A

    2010-05-01

    Global warming accelerates decomposition of soil organic carbon (SOC) pools with varying rates and temperature sensitivities. Black carbon (BC) materials are among the slowest decomposing components of the SOC pool. Although BC is a large component of SOC in many systems, the influence of temperature on decomposition of BC bearing different chemical and physical structures remains poorly understood. Four BC materials, produced by carbonizing corn residue and oak wood at 350 and 600 degrees C (corn-350-BC, corn-600-BC, oak-350-BC, and oak-600-BC), were mixed with pure sand and incubated at 4, 10, 20, 30, 45, and 60 degrees C for 1 year. Corn-BC was more porous than oak-BC as determined by scanning electron microscopy (SEM). Increasing the charring temperature from 350 to 600 degrees C led to greater aromaticity with 5-15% more C in aromatic rings and a 39-57% increase in both nonprotonated aromatic C and aromatic bridgehead C quantified by nuclear magnetic resonance (NMR) spectroscopy and a greater degree of order and development of C layers as observed by transmission electron microscopy (TEM). With a temperature increase from 4 to 60 degrees C, C loss of corn-350-BC increased from 10 to 20%, corn-600-BC, from 4 to 20%, oak-350-BC, from 2.3 to 15%, and oak-600-BC from 1.5 to 14% of initial C content, respectively. Temperature sensitivity (Q(10)) decreased with increasing incubation temperature and was highest in oak-600-BC, followed by oak-350-BC, corn-600-BC, and corn-350-BC, indicating that decomposition of more stable BC was more sensitive to increased temperature than less stable materials. Carbon loss and potential cation exchange capacity (CECp) significantly (p < 0.05) correlated with O/C ratios and change in O/C ratios, suggesting that oxidative processes were the most important mechanism controlling BC decomposition in this study. PMID:20384335

  17. The Early Infrared Temporal Development of Nova Delphini 2013 (V339 DEL) Observed with the Stratospheric Observatory for Infrared Astronomy (SOFIA) and from the Ground

    NASA Astrophysics Data System (ADS)

    Gehrz, R. D.; Evans, A.; Helton, L. A.; Shenoy, D. P.; Banerjee, D. P. K.; Woodward, C. E.; Vacca, W. D.; Dykhoff, D. A.; Ashok, N. M.; Cass, A. C.; Carlon, R. L.; Corgan, D. T.; Eyres, S. P. S.; Joshi, V.; Keller, Luke D.; Krautter, J.; Liimets, T.; Rushton, M.; Starrfield, S.

    2015-10-01

    We present ground-based infrared photometry, JHK spectroscopy, and 5–28 ?m SOFIA FORCAST spectroscopy documenting the early temporal development of Nova Delphini 2013 (V339 Del). We derive a distance of ?4.5 kpc using data available from the early expansion of the fireball. This distance gives an outburst luminosity of ?8.3 × 105 {L}? making V339 Del the most luminous CO nova on record. Our data provide new constraints on the ejected gas mass and the dust yield in fast CO novae. The ejected gas mass as estimated by the cutoff wavelength during the free–free emission phase is ?7.5 × 10?5 {M}? . There is evidence for the formation of ?1.2(±0.4) × 10?7 {M}? of dust about 102 days after outburst. The gas to dust ratio of ?470/1–940/1 implies that dust production was much less efficient in V339 Del than is the case for most CO novae.

  18. Combined MIPAS (airborne/satellite), CALIPSO and in situ study on large potential NAT particles observed in early Arctic winter stratosphere in December 2011

    NASA Astrophysics Data System (ADS)

    Woiwode, Wolfgang; Höpfner, Michael; Pitts, Michael; Poole, Lamont; Oelhaf, Hermann; Molleker, Sergej; Borrmann, Stephan; Ebersoldt, Andreas; Frey, Wiebke; Gulde, Thomas; Maucher, Guido; Piesch, Christof; Sartorius, Christian; Orphal, Johannes

    2015-04-01

    The understanding of the characteristics of large HNO3-containing particles (potential 'NAT-rocks') involved in vertical redistribution of HNO3 in the polar winter stratosphere is limited due to the difficult accessibility of these particles by observations. While robust polar stratospheric cloud (PSC) classification schemes exist for observations by the space-borne lidar aboard CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) as well as for the passive mid-infrared limb observations by MIPAS (Michelson Interferometer for Passive Atmospheric Sounding), these observations are hardly exploited for the detection of large (diameter >10 ?m) NAT particles. This is due to the facts that these particles have low overall number densities, resulting in weak detectable signatures, and that the physical characteristics of these particles (i.e. shape, morphology, HNO3-content and optical characteristics) are uncertain. We investigate collocated and complementary observations of a low-density potential large NAT particle field by the space-borne instruments CALIPSO and MIPAS-ENVISAT as well as the airborne observations by the limb-sounder MIPAS-STR and the in situ particle probe FSSP-100 (Forward Scattering Spectrometer Probe 100) aboard the high-altitude aircraft Geophysica. The observations aboard the Geophysica on 11 December 2011 associated to ESSenCe (ESa Sounder Campaign 2011) provided us the unique opportunity to study in detail the lower boundary region of a PSC where large potential NAT particles (>20 ?m in diameter) were detected in situ. We analyse the ambient temperatures and gas-phase composition (HNO3 and H2O), the signatures of the observed particles in the CALIPSO and MIPAS observations, the HNO3-content of these particles suggested by the FSSP-100 and MIPAS-STR observations, and focus on the spectral fingerprint of these particles in the MIPAS-STR observations. While the spectral characterisation of the observed particles is subject of ongoing work, our results support that these particles consist of NAT and that the particle shape plays a crucial role.

  19. Early Earth

    NASA Astrophysics Data System (ADS)

    Brown, M.

    2015-05-01

    Earth has continents, subduction and mobile lid plate tectonics, but details of the early evolution are poorly understood. Here I summarize the Hadean-Archean record, review evidence for a hotter Earth and consider geodynamic models for early Earth.

  20. Understanding litter decomposition in semiarid ecosystems: linking leaf traits, UV exposure and rainfall variability.

    PubMed

    Gaxiola, Aurora; Armesto, Juan J

    2015-01-01

    Differences in litter quality, microbial activity or abiotic conditions cannot fully account for the variability in decomposition rates observed in semiarid ecosystems. Here we tested the role of variation in litter quality, water supply, and UV radiation as drivers of litter decomposition in arid lands. And show that carry-over effects of litter photodegradation during dry periods can regulate decomposition during subsequent wet periods. We present data from a two-phase experiment, where we first exposed litter from a drought-deciduous and an evergreen shrub to natural UV levels during five, rainless summer months and, subsequently, in the laboratory, we assessed the carry-over effects of photodegradation on biomass loss under different irrigation treatments representing the observed range of local rainfall variation among years (15-240 mm). Photodegradation of litter in the field produced average carbon losses of 12%, but deciduous Proustia pungens lost >25%, while evergreen Porlieria chilensis less than 5%. Natural exposure to UV significantly reduced carbon-to-nitrogen and lignin:N ratios in Proustia litter but not in Porlieria. During the subsequent wet phase, remaining litter biomass was lower in Proustia than in Porlieria. Indeed UV exposure increased litter decomposition of Proustia under low and medium rainfall treatments, whereas no carry-over effects were detected under high rainfall treatment. Consequently, for deciduous Proustia carry-over effects of UV exposure were negligible under high irrigation. Litter decomposition of the evergreen Porlieria depended solely on levels of rainfall that promote microbial decomposers. Our two-phase experiment revealed that both the carry-over effects of photodegradation and litter quality, modulated by inter-annual variability in rainfall, can explain the marked differences in decomposition rates and the frequent decoupling between rainfall and litter decomposition observed in semiarid ecosystems. PMID:25852705

  1. Understanding litter decomposition in semiarid ecosystems: linking leaf traits, UV exposure and rainfall variability

    PubMed Central

    Gaxiola, Aurora; Armesto, Juan J.

    2015-01-01

    Differences in litter quality, microbial activity or abiotic conditions cannot fully account for the variability in decomposition rates observed in semiarid ecosystems. Here we tested the role of variation in litter quality, water supply, and UV radiation as drivers of litter decomposition in arid lands. And show that carry-over effects of litter photodegradation during dry periods can regulate decomposition during subsequent wet periods. We present data from a two-phase experiment, where we first exposed litter from a drought-deciduous and an evergreen shrub to natural UV levels during five, rainless summer months and, subsequently, in the laboratory, we assessed the carry-over effects of photodegradation on biomass loss under different irrigation treatments representing the observed range of local rainfall variation among years (15–240 mm). Photodegradation of litter in the field produced average carbon losses of 12%, but deciduous Proustia pungens lost >25%, while evergreen Porlieria chilensis less than 5%. Natural exposure to UV significantly reduced carbon-to-nitrogen and lignin:N ratios in Proustia litter but not in Porlieria. During the subsequent wet phase, remaining litter biomass was lower in Proustia than in Porlieria. Indeed UV exposure increased litter decomposition of Proustia under low and medium rainfall treatments, whereas no carry-over effects were detected under high rainfall treatment. Consequently, for deciduous Proustia carry-over effects of UV exposure were negligible under high irrigation. Litter decomposition of the evergreen Porlieria depended solely on levels of rainfall that promote microbial decomposers. Our two-phase experiment revealed that both the carry-over effects of photodegradation and litter quality, modulated by inter-annual variability in rainfall, can explain the marked differences in decomposition rates and the frequent decoupling between rainfall and litter decomposition observed in semiarid ecosystems. PMID:25852705

  2. Sensitivity of soil organic matter decomposition to simultaneous changes in temperature and moisture

    NASA Astrophysics Data System (ADS)

    Sierra, Carlos; Trumbore, Susan; Davidson, Eric; Vicca, Sara; Janssens, Ivan

    2014-05-01

    Soil organic matter decomposition depends on multiple factors that are being altered simultaneously as a result of global environmental change. For this reason it is important to study the overall sensitivity of soil organic matter decomposition with respect to multiple and interacting drivers. Here we present an analysis of the potential response of decomposition rates to simultaneous changes in temperature and moisture. To address this problem, we first present a theoretical framework to study the sensitivity of soil organic matter decomposition when multiple driving factors change simultaneously. We then apply this framework to models and data at different levels of abstraction: 1) to a mechanistic model that addresses the limitation of enzyme activity by simultaneous effects of temperature and soil water content, the latter controlling substrate supply and oxygen concentration for microbial activity; 2) to different mathematical functions used to represent temperature and moisture effects on decomposition in biogeochemical models. To contrast model predictions at these two levels of organization, we compiled different datasets of observed responses in field and laboratory studies. Then we applied our conceptual framework to: 3) observations of soil respiration at the ecosystem level; 4) laboratory experiments looking at the response of heterotrophic respiration to independent changes in moisture and temperature; and 5) ecosystem-level experiments manipulating soil temperature and water content simultaneously. The combined theoretical and empirical evidence reviewed suggests: first, large uncertainties still remain regarding the combined controls of temperature and moisture on decomposition rates, particularly at high temperatures and the extremes of the soil moisture range; second, the highest sensitivities of decomposition rates are likely in systems where temperature and moisture are high such as tropical peatlands, and at temperatures near the freezing point of water such as in soils under freeze-thaw cycles. These regions also exhibit the largest differences in projected changes in decomposition rates among different models. Third, the lowest sensitivity of decomposition rates to changes in temperature and moisture is expected in soils with temperatures well below the freezing point. Uncertainty in models can be reduced if some of the functions representing the effects of temperature and moisture on decomposition can be discredited based on empirical observations or experiments.

  3. Phase Diagram and Decomposition of 1,1-Diamino-2,2-Dinitroethene (FOX-7)

    NASA Astrophysics Data System (ADS)

    Tao, Yuchuan; Dreger, Zbigniew; Gupta, Yogendra

    2015-06-01

    To understand the reactive behavior of 1,1-diamino-2,2-dinitroethene (FOX-7) at the thermo-mechanical conditions relevant to shock-wave initiation, Raman and FTIR measurements were performed at high-pressures (HP) and high-temperatures (HT). Experiments were performed on single crystals of FOX-7 in a diamond anvil cell to 10 GPa and 800 K to provide the phase diagram and to gain insight into the HP decomposition mechanisms. Previous studies have demonstrated that the ambient structure of FOX-7 (alpha) transforms to beta and gamma phases at higher temperatures, and phase I (2 GPa) and II (4.5 GPa) at higher pressures. In this work, we determined the boundaries between these phases and the decomposition/melting curve. In particular, we found that: (i) both beta and gamma phases exist in a limited P-T domain (>386 K and <1 GPa), (ii) the transition between phase-I and phase-II takes place along the isobar, (iii) the decomposition temperature increases significantly with pressure (~ 25 K / GPa), and (iv) pressure inhibits the decomposition. Using FTIR spectroscopy, we observed that CO2 is the first dominating decomposition product, followed by N2O, NO2, HCN, and HNCO. Pressure effects on reaction kinetics will be presented along with the possible mechanisms of decomposition. Work supported by DOE/NNSA and ONR.

  4. The Nonexistence ofa (K6-e)-Decomposition

    E-print Network

    Hartke, Stephen

    The Nonexistence ofa (K6-e)-Decomposition ofthe Complete Graph K29 S. G. Hartke,1 P. R. J. ¨Osterg a (K6 -e)- decomposition of K29. This is the first example of a non-complete graph G for which a G-decomposition; complete graph; graph decomposition; isomorph rejection 1. INTRODUCTION Let G and K be graphs. A G-decomposition

  5. Integrated SeismoGeodetic Systsem with High-Resolution, Real-Time GNSS and Accelerometer Observation For Earthquake Early Warning Application.

    NASA Astrophysics Data System (ADS)

    Passmore, P. R.; Jackson, M.; Zimakov, L. G.; Raczka, J.; Davidson, P.

    2014-12-01

    The key requirements for Earthquake Early Warning and other Rapid Event Notification Systems are: Quick delivery of digital data from a field station to the acquisition and processing center; Data integrity for real-time earthquake notification in order to provide warning prior to significant ground shaking in the given target area. These two requirements are met in the recently developed Trimble SG160-09 SeismoGeodetic System, which integrates both GNSS and acceleration measurements using the Kalman filter algorithm to create a new high-rate (200 sps), real-time displacement with sufficient accuracy and very low latency for rapid delivery of the acquired data to a processing center. The data acquisition algorithm in the SG160-09 System provides output of both acceleration and displacement digital data with 0.2 sec delay. This is a significant reduction in the time interval required for real-time transmission compared to data delivery algorithms available in digitizers currently used in other Earthquake Early Warning networks. Both acceleration and displacement data are recorded and transmitted to the processing site in a specially developed Multiplexed Recording Format (MRF) that minimizes the bandwidth required for real-time data transmission. In addition, a built in algorithm calculates the ?c and Pd once the event is declared. The SG160-09 System keeps track of what data has not been acknowledged and re-transmits the data giving priority to current data. Modified REF TEK Protocol Daemon (RTPD) receives the digital data and acknowledges data received without error. It forwards this "good" data to processing clients of various real-time data processing software including Earthworm and SeisComP3. The processing clients cache packets when a data gap occurs due to a dropped packet or network outage. The cache packet time is settable, but should not exceed 0.5 sec in the Earthquake Early Warning network configuration. The rapid data transmission algorithm was tested with different communication media, including Internet, DSL, Wi-Fi, GPRS, etc. The test results show that the data latency via most communication media do not exceed 0.5 sec nominal from a first sample in the data packet. Detailed acquisition algorithm and results of data transmission via different communication media are presented.

  6. Unimolecular thermal decomposition of dimethoxybenzenes

    SciTech Connect

    Robichaud, David J. Mukarakate, Calvin; Nimlos, Mark R.; Scheer, Adam M.; Ormond, Thomas K.; Buckingham, Grant T.; Ellison, G. Barney

    2014-06-21

    The unimolecular thermal decomposition mechanisms of o-, m-, and p-dimethoxybenzene (CH{sub 3}O-C{sub 6}H{sub 4}-OCH{sub 3}) have been studied using a high temperature, microtubular (?tubular) SiC reactor with a residence time of 100 ?s. Product detection was carried out using single photon ionization (SPI, 10.487 eV) and resonance enhanced multiphoton ionization (REMPI) time-of-flight mass spectrometry and matrix infrared absorption spectroscopy from 400 K to 1600 K. The initial pyrolytic step for each isomer is methoxy bond homolysis to eliminate methyl radical. Subsequent thermolysis is unique for each isomer. In the case of o-CH{sub 3}O-C{sub 6}H{sub 4}-OCH{sub 3}, intramolecular H-transfer dominates leading to the formation of o-hydroxybenzaldehyde (o-HO-C{sub 6}H{sub 4}-CHO) and phenol (C{sub 6}H{sub 5}OH). Para-CH{sub 3}O-C{sub 6}H{sub 4}-OCH{sub 3} immediately breaks the second methoxy bond to form p-benzoquinone, which decomposes further to cyclopentadienone (C{sub 5}H{sub 4}=O). Finally, the m-CH{sub 3}O-C{sub 6}H{sub 4}-OCH{sub 3} isomer will predominantly follow a ring-reduction/CO-elimination mechanism to form C{sub 5}H{sub 4}=O. Electronic structure calculations and transition state theory are used to confirm mechanisms and comment on kinetics. Implications for lignin pyrolysis are discussed.

  7. Aridity and decomposition processes in complex landscapes

    NASA Astrophysics Data System (ADS)

    Ossola, Alessandro; Nyman, Petter

    2015-04-01

    Decomposition of organic matter is a key biogeochemical process contributing to nutrient cycles, carbon fluxes and soil development. The activity of decomposers depends on microclimate, with temperature and rainfall being major drivers. In complex terrain the fine-scale variation in microclimate (and hence water availability) as a result of slope orientation is caused by differences in incoming radiation and surface temperature. Aridity, measured as the long-term balance between net radiation and rainfall, is a metric that can be used to represent variations in water availability within the landscape. Since aridity metrics can be obtained at fine spatial scales, they could theoretically be used to investigate how decomposition processes vary across complex landscapes. In this study, four research sites were selected in tall open sclerophyll forest along a aridity gradient (Budyko dryness index ranging from 1.56 -2.22) where microclimate, litter moisture and soil moisture were monitored continuously for one year. Litter bags were packed to estimate decomposition rates (k) using leaves of a tree species not present in the study area (Eucalyptus globulus) in order to avoid home-field advantage effects. Litter mass loss was measured to assess the activity of macro-decomposers (6mm litter bag mesh size), meso-decomposers (1 mm mesh), microbes above-ground (0.2 mm mesh) and microbes below-ground (2 cm depth, 0.2 mm mesh). Four replicates for each set of bags were installed at each site and bags were collected at 1, 2, 4, 7 and 12 months since installation. We first tested whether differences in microclimate due to slope orientation have significant effects on decomposition processes. Then the dryness index was related to decomposition rates to evaluate if small-scale variation in decomposition can be predicted using readily available information on rainfall and radiation. Decomposition rates (k), calculated fitting single pool negative exponential models, generally decreased with increasing aridity with k going from 0.0025 day-1 on equatorial (dry) facing slopes to 0.0040 day-1 on polar (wet) facing slopes. However, differences in temperature as a result of morning vs afternoon sun on east and west aspects, respectively, (not captured in the aridity metric) resulted in poor prediction of decomposition for the sites located in the intermediate aridity range. Overall the results highlight that relatively small differences in microclimate due to slope orientation can have large effects on decomposition. Future research will aim to refine the aridity metric to better resolve small scale variation in surface temperature which is important when up-scaling decomposition processes to landscapes.

  8. Decomposition of diazomeldrum's acid: a threshold photoelectron spectroscopy study.

    PubMed

    Lang, Melanie; Holzmeier, Fabian; Fischer, Ingo; Hemberger, Patrick

    2014-11-26

    Derivatives of meldrum's acid are known precursors for a number of reactive intermediates. Therefore, we investigate diazomeldrum's acid (DMA) and its pyrolysis products by photoionization using vacuum ultraviolet (VUV) synchrotron radiation. The threshold photoelectron spectrum of DMA yields an ionization energy (IE) of 9.68 eV. Several channels for dissociative photoionization are observed. The first one is associated with loss of CH3, leading to a daughter ion with m/z = 155. Its appearance energy AE0K was determined to be 10.65 eV by fitting the experimental data using statistical theory. A second parallel channel leads to m/z = 69, corresponding to N2CHCO, with an AE0K of 10.72 eV. Several other channels open up at higher energy, among them the formation of acetone cation, a channel expected to be the result of a Wolff-rearrangement (WR) in the cation. When diazomeldrum's acid is heated in a pyrolysis reactor, three thermal decomposition pathways are observed. The major one is well-known and yields acetone, N2 and CO as consequence of the WR. However, two further channels were identified: The formation of 2-diazoethenone, NNCCO, together with acetone and CO2 as the second channel and E-formylketene (OCCHCHCO), propyne, N2 and O2 as a third one. 2-Diazoethenone and E-formylketene were identified based on their threshold photoelectron spectra and accurate ionization energies could be determined. Ionization energies for several isomers of both molecules were also computed. One of the key findings of this study is that acetone is observed upon decomposition of DMA in the neutral as well as in the ion and both point to a Wolff rearrangement to occur. However, the ion is subject to other decomposition channels favored at lower internal energies. PMID:25369422

  9. Regarding the Potential Impact of Double Star Observations on Conceptions of the Universe of Stars in the Early 17TH Century

    E-print Network

    Graney, Christopher M

    2008-01-01

    Galileo Galilei believed that stars were distant suns whose sizes measured via his telescope were a direct indication of distance -- fainter stars (appearing smaller in the telescope) being farther away than brighter ones. Galileo argued in his Dialogue that telescopic observation of a chance alignment of a faint (distant) and bright (closer) star would reveal annual parallax, if such double stars were found. This would provide support both for Galileo's ideas concerning the nature of stars and for the motion of the Earth. However, Galileo actually made observations of such double stars, well before publication of the Dialogue. We show that the results of these observations, and the likely results of observations of any double star that was a viable subject for Galileo's telescope, would undermine Galileo's ideas, not support them. We argue that such observations would lead either to the more correct idea that stars were sun-like bodies of varying sizes which could be physically grouped, or to the less correc...

  10. Decomposition of forest products buried in landfills

    SciTech Connect

    Wang, Xiaoming; Padgett, Jennifer M.; Powell, John S.; Barlaz, Morton A.

    2013-11-15

    Highlights: • This study tracked chemical changes of wood and paper in landfills. • A decomposition index was developed to quantify carbohydrate biodegradation. • Newsprint biodegradation as measured here is greater than previous reports. • The field results correlate well with previous laboratory measurements. - Abstract: The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g{sup ?1} dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported.

  11. Deep Coastal Marine Taphonomy: Investigation into Carcass Decomposition in the Saanich Inlet, British Columbia Using a Baited Camera

    PubMed Central

    Anderson, Gail S.; Bell, Lynne S.

    2014-01-01

    Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensic investigations involving submerged bodies, indicating types of water conditions to which the body has been exposed, identifying post-mortem artifacts and providing realistic expectations for recovery divers and families of the deceased. PMID:25329759

  12. Oxidative decomposition of formaldehyde catalyzed by a bituminous coal

    SciTech Connect

    Haim Cohen; Uri Green

    2009-05-15

    It has been observed that molecular hydrogen is formed during long-term storage of bituminous coals via oxidative decomposition of formaldehyde by coal surface peroxides. This study has investigated the effects of coal quantity, temperature, and water content on the molecular hydrogen formation with a typical American coal (Pittsburgh No. 6). The results indicate that the coal's surface serves as a catalyst in the formation processes of molecular hydrogen. Furthermore, the results also indicate that low temperature emission of molecular hydrogen may possibly be the cause of unexplained explosions in confined spaces containing bituminous coals, for example, underground mines or ship holds. 20 refs., 4 figs., 6 tabs.

  13. A self-adjoint decomposition of the radial momentum operator

    NASA Astrophysics Data System (ADS)

    Liu, Q. H.; Xiao, S. F.

    2015-12-01

    With acceptance of the Dirac's observation that the canonical quantization entails using Cartesian coordinates, we examine the operator erPr rather than Pr itself and demonstrate that there is a decomposition of erPr into a difference of two self-adjoint but noncommutative operators, in which one is the total momentum and another is the transverse one. This study renders the operator Pr indirectly measurable and physically meaningful, offering an explanation of why the mean value of Pr over a quantum mechanical state makes sense and supporting Dirac's claim that Pr "is real and is the true momentum conjugate to r".

  14. Fragment Charge Correlations and Spinodal Decomposition in Finite Nuclear Systems

    E-print Network

    G. Tabacaru; B. Borderie; P. Desesquelles; M. Parlog; M. F. Rivet

    2003-07-04

    Enhanced production of events with almost equal-sized fragments is experimentally revealed by charge correlations in the multifragmentation of a finite nuclear system selected in $^{129}$Xe central collisions on $^{nat}$Sn. The evolution of their weight with the incident energy: 32, 39, 45, 50 AMeV, is measured.Dynamical stochastic mean field simulations performed at 32 AMeV, in which spinodal instabilities are responsible for multifragmentation, exhibit a similar enhancement of this kind of events. The above experimental observation evidences the spinodal decomposition of hot finite nuclear matter as the origin of multifragmentation in the Fermi energy regime.

  15. Plant roots alter microbial potential for mediation of soil organic carbon decomposition

    NASA Astrophysics Data System (ADS)

    Firestone, M.; Shi, S.; Herman, D.; He, Z.; Zhou, J.

    2014-12-01

    Plant root regulation of soil organic carbon (SOC) decomposition is a key controller of terrestrial C-cycling. Although many studies have tested possible mechanisms underlying plant "priming" of decomposition, few have investigated the microbial mediators of decomposition, which can be greatly influenced by plant activities. Here we examined effects of Avena fatua roots on decomposition of 13C-labeled root litter in a California grassland soil over two simulated growing-seasons. The presence of plant roots consistently suppressed rates of litter decomposition. Reduction of inorganic nitrogen (N) concentration in soil reduced but did not completely relieve this suppressive effect. The presence of plants significantly altered the abundance, composition and functional potential of microbial communities. Significantly higher signal intensities of genes capable of degrading low molecular weight organic compounds (e.g., glucose, formate and malate) were observed in microbial communities from planted soils, while microorganisms in unplanted soils had higher relative abundances of genes involved in degradation of some macromolecules (e.g., hemicellulose and lignin). Additionally, compared to unplanted soils, microbial communities from planted soils had higher signal intensities of proV and proW, suggesting microbial osmotic stress in planted soils. Possible mechanisms for the observed inhibition of decomposition are 1) microbes preferentially using simple substrates from root exudates and 2) soil drying by plant evapotranspiration impairing microbial activity. We propose a simple data-based model suggesting that the impacts of roots, the soil environment, and microbial community composition on decomposition processes result from impacts of these factors on the soil microbial functional gene potential.

  16. Development of a Novel Catalyst for No Decomposition

    SciTech Connect

    Ates Akyurtlu; Jale Akyurtlu

    2007-06-22

    Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NO{sub x} emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N{sub 2} will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation leads one to believe that the Pt/SnO{sub 2} catalysts may have a potential as NO decomposition catalysts in the presence of oxygen. This prediction is also supported by some preliminary data obtained for NO decomposition on a Pt/SnO{sub 2} catalyst in the PI's laboratory. The main objective of the research that is being undertaken is the evaluation of the Pt/SnO{sub 2} catalysts for the decomposition of NO in simulated power plant stack gases with particular attention to the resistance to deactivation by O{sub 2}, H{sub 2}O, and elevated temperatures. Temperature programmed desorption (TPD) and temperature programmed reaction (TPRx) studies on Pt/SnO{sub 2} catalysts having different noble metal concentrations and pretreated under different conditions were done. It is also planned to perform NO decomposition tests in a laboratory-size packed-bed reactor to obtain long-term deactivation data. Temperature programmed desorption and temperature controlled reaction runs were made with catalysts containing 15% Pt and 10% Pt on SnO{sub 2}. Catalysts containing 10% Pt resulted in significantly lower activities than 15% PT catalysts. Therefore, in the remainder of the tests 15% Pt/SnO{sub 2} catalysts were used. Isothermal reaction studies were made to elucidate the effects of temperature, oxygen, water vapor, pretreatment temperature, and space velocity on NO dissociation. It was found that the presence of oxygen and water vapor did not affect the activation energy of the NO dissociation reaction indicating the presence of the same rate controlling step for all feed compositions. Activation energy was higher for higher gas velocities suggesting the presence of mass transfer limitations at lower velocities. Presence of oxygen in the feed inhibited the NO decomposition. Having water vapor in the feed did not significantly affect the catalyst activity for catalysts pretreated at 373 K, but significantly reduced catalyst activity for catalysts pretreated at 900 K. Long-term deactivation studies indicated that the catalyst deactivated slowly both with and without the presence of added oxygen in the feed, Deactivation started later in the presence of oxygen. The activities of the catalysts investigated were too low below 1000 K for commercial applications. Their selectivity towards N{sub 2} was good at temperatures above 700 K. A different method for catalyst preparation is needed to improve the catalyst performance.

  17. MAGIC gamma-ray and multi-frequency observations of flat spectrum radio quasar PKS 1510-089 in early 2012

    NASA Astrophysics Data System (ADS)

    Aleksi?, J.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Babic, A.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Carmona, E.; Carosi, A.; Carreto Fidalgo, D.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Caneva, G.; De Lotto, B.; Delgado Mendez, C.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher, D.; Elsaesser, D.; Farina, E.; Ferenc, D.; Fonseca, M. V.; Font, L.; Frantzen, K.; Fruck, C.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Godinovi?, N.; González Muñoz, A.; Gozzini, S. R.; Hadasch, D.; Hayashida, M.; Herrera, J.; Herrero, A.; Hildebrand, D.; Hose, J.; Hrupec, D.; Idec, W.; Kadenius, V.; Kellermann, H.; Kodani, K.; Konno, Y.; Krause, J.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lewandowska, N.; Lindfors, E.; Lombardi, S.; López, M.; López-Coto, R.; López-Oramas, A.; Lorenz, E.; Lozano, I.; Makariev, M.; Mallot, K.; Maneva, G.; Mankuzhiyil, N.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Meucci, M.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Munar-Adrover, P.; Nakajima, D.; Niedzwiecki, A.; Nilsson, K.; Nishijima, K.; Noda, K.; Nowak, N.; Orito, R.; Overkemping, A.; Paiano, S.; Palatiello, M.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Partini, S.; Persic, M.; Prada, F.; Prada Moroni, P. G.; Prandini, E.; Preziuso, S.; Puljak, I.; Reinthal, R.; Rhode, W.; Ribó, M.; Rico, J.; Rodriguez Garcia, J.; Rügamer, S.; Saggion, A.; Saito, T.; Saito, K.; Satalecka, K.; Scalzotto, V.; Scapin, V.; Schultz, C.; Schweizer, T.; Shore, S. N.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Spanier, F.; Stamatescu, V.; Stamerra, A.; Steinbring, T.; Storz, J.; Strzys, M.; Sun, S.; Suri?, T.; Takalo, L.; Takami, H.; Tavecchio, F.; Temnikov, P.; Terzi?, T.; Tescaro, D.; Teshima, M.; Thaele, J.; Tibolla, O.; Torres, D. F.; Toyama, T.; Treves, A.; Uellenbeck, M.; Vogler, P.; Wagner, R. M.; Zandanel, F.; Zanin, R.; MAGIC Collaboration; Lucarelli, F.; Pittori, C.; Vercellone, S.; Verrecchia, F.; AGILE Collaboration; Buson, S.; D'Ammando, F.; Stawarz, L.; Giroletti, M.; Orienti, M.; Fermi-LAT Collaboration; Mundell, C.; Steele, I.; Zarpudin, B.; Raiteri, C. M.; Villata, M.; Sandrinelli, A.; Lähteenmäki, A.; Tammi, J.; Tornikoski, M.; Hovatta, T.; Readhead, A. C. S.; Max-Moerbeck, W.; Richards, J. L.; Jorstad, S.; Marscher, A.; Gurwell, M. A.; Larionov, V. M.; Blinov, D. A.; Konstantinova, T. S.; Kopatskaya, E. N.; Larionova, L. V.; Larionova, E. G.; Morozova, D. A.; Troitsky, I. S.; Mokrushina, A. A.; Pavlova, Yu. V.; Chen, W. P.; Lin, H. C.; Panwar, N.; Agudo, I.; Casadio, C.; Gómez, J. L.; Molina, S. N.; Kurtanidze, O. M.; Nikolashvili, M. G.; Kurtanidze, S. O.; Chigladze, R. A.; Acosta-Pulido, J. A.; Carnerero, M. I.; Manilla-Robles, A.; Ovcharov, E.; Bozhilov, V.; Metodieva, I.; Aller, M. F.; Aller, H. D.; Fuhrman, L.; Angelakis, E.; Nestoras, I.; Krichbaum, T. P.; Zensus, J. A.; Ungerechts, H.; Sievers, A.

    2014-09-01

    Aims: Amongst more than fifty blazars detected in very high energy (VHE, E> 100 GeV) ? rays, only three belong to the subclass of flat spectrum radio quasars (FSRQs). The detection of FSRQs in the VHE range is challenging, mainly because of their soft spectra in the GeV-TeV regime. MAGIC observed PKS 1510-089 (z = 0.36) starting 2012 February 3 until April 3 during a high activity state in the high energy (HE, E> 100 MeV) ?-ray band observed by AGILE and Fermi. MAGIC observations result in the detection of a source with significance of 6.0 standard deviations (?). We study the multi-frequency behaviour of the source at the epoch of MAGIC observation, collecting quasi-simultaneous data at radio and optical (GASP-WEBT and F-Gamma collaborations, REM, Steward, Perkins, Liverpool, OVRO, and VLBA telescopes), X-ray (Swift satellite), and HE ?-ray frequencies. Methods: We study the VHE ?-ray emission, together with the multi-frequency light curves, 43 GHz radio maps, and spectral energy distribution (SED) of the source. The quasi-simultaneous multi-frequency SED from the millimetre radio band to VHE ? rays is modelled with a one-zone inverse Compton model. We study two different origins of the seed photons for the inverse Compton scattering, namely the infrared torus and a slow sheath surrounding the jet around the Very Long Baseline Array (VLBA) core. Results: We find that the VHE ?-ray emission detected from PKS 1510-089 in 2012 February-April agrees with the previous VHE observations of the source from 2009 March-April. We find no statistically significant variability during the MAGIC observations on daily, weekly, or monthly time scales, while the other two known VHE FSRQs (3C 279 and PKS 1222+216) have shown daily scale to sub-hour variability. The ?-ray SED combining AGILE, Fermi and MAGIC data joins smoothly and shows no hint of a break. The multi-frequency light curves suggest a common origin for the millimetre radio and HE ?-ray emission, and the HE ?-ray flaring starts when the new component is ejected from the 43 GHz VLBA core and the studied SED models fit the data well. However, the fast HE ?-ray variability requires that within the modelled large emitting region, more compact regions must exist. We suggest that these observed signatures would be most naturally explained by a turbulent plasma flowing at a relativistic speed down the jet and crossing a standing conical shock.

  18. The Schmidt-Kennicutt Law of Matched-Age Star Forming Regions; Pa-alpha Observations of the Early-Phase Interacting Galaxy Taffy I

    E-print Network

    Komugi, S; Motohara, K; Takagi, T; Iono, D; Kaneko, H; Ueda, J; Saitoh, T R; Kato, N; Konishi, M; Koshida, S; Morokuma, T; Takahashi, H; Tanabe, T; Yoshii, Y

    2012-01-01

    In order to test a recent hypothesis that the dispersion in the Schmidt-Kennicutt law arises from variations in the evolutionary stage of star forming molecular clouds, we compared molecular gas and recent star formation in an early-phase merger galaxy pair, Taffy I (UGC\\ 12915/UGC\\ 12914, VV\\ 254) which went through a direct collision 20 Myr ago and whose star forming regions are expected to have similar ages. Narrow-band Pa-alpha image is obtained using the ANIR near-infrared camera on the mini-TAO 1m telescope. The image enables us to derive accurate star formation rates within the galaxy directly. The total star formation rate, 22.2 M_sun/yr, was found to be much higher than previous estimates. Ages of individual star forming blobs estimated from equivalent widths indicate that most star forming regions are ~7 Myr old, except for a giant HII region at the bridge which is much younger. Comparison between star formation rates and molecular gas masses for the regions with the same age exhibits a surprisingly...

  19. Steganography based on pixel intensity value decomposition

    NASA Astrophysics Data System (ADS)

    Abdulla, Alan Anwar; Sellahewa, Harin; Jassim, Sabah A.

    2014-05-01

    This paper focuses on steganography based on pixel intensity value decomposition. A number of existing schemes such as binary, Fibonacci, Prime, Natural, Lucas, and Catalan-Fibonacci (CF) are evaluated in terms of payload capacity and stego quality. A new technique based on a specific representation is proposed to decompose pixel intensity values into 16 (virtual) bit-planes suitable for embedding purposes. The proposed decomposition has a desirable property whereby the sum of all bit-planes does not exceed the maximum pixel intensity value, i.e. 255. Experimental results demonstrate that the proposed technique offers an effective compromise between payload capacity and stego quality of existing embedding techniques based on pixel intensity value decomposition. Its capacity is equal to that of binary and Lucas, while it offers a higher capacity than Fibonacci, Prime, Natural, and CF when the secret bits are embedded in 1st Least Significant Bit (LSB). When the secret bits are embedded in higher bit-planes, i.e., 2nd LSB to 8th Most Significant Bit (MSB), the proposed scheme has more capacity than Natural numbers based embedding. However, from the 6th bit-plane onwards, the proposed scheme offers better stego quality. In general, the proposed decomposition scheme has less effect in terms of quality on pixel value when compared to most existing pixel intensity value decomposition techniques when embedding messages in higher bit-planes.

  20. Thermal decomposition of glycidyl azide polymer studied by synchrotron photoionization mass spectrometry.

    PubMed

    Wang, Tianfang; Li, Shufen; Yang, Bin; Huang, Chaoqun; Li, Yuyang

    2007-03-15

    In this work, the thermal decomposition reactions and products of glycidyl azide polymer (GAP) at low pressure have been investigated by tunable synchrotron vacuum ultraviolet (VUV) photoionization and molecular-beam sampling mass spectrometry. It has been observed that thermal decomposition of GAP began at a lower temperature (about 70 degrees C), compared to about 170 degrees C in the air. Most observed species in the thermal decomposition process have been clearly identified by measurements of the photoionization mass spectrum and photoionization efficiency (PIE) spectra. Many species have been detected at the initiation of the degradation. Compared with previous studies on thermal decomposition of GAP, some free radicals, such as C2H3O, C3H5O, C6H6N, C3H5ON3, and so forth, have been identified in the present work. The formation mechanisms of some important radicals have been discussed, and the most probable reaction routines have also been proposed, which should be of importance in understanding the energy-releasing mechanism of GAP thermal decomposition. PMID:17309290

  1. Early lunar geology and geophysics

    E-print Network

    Garrick-Bethell, Ian, 1980-

    2009-01-01

    Despite a number of human and robotic missions to the Moon, there are still important unanswered questions about its early evolution, and how it came to be the object we observe today. Here we use observational, experimental, ...

  2. The second-generation z (redshift) and early universe spectrometer. I. First-light observation of a highly lensed local-ulirg analog at high-z

    SciTech Connect

    Ferkinhoff, Carl; Brisbin, Drew; Parshley, Stephen; Nikola, Thomas; Stacey, Gordon J.; Schoenwald, Justin; Riechers, Dominik; Higdon, James L.; Higdon, Sarah J. U.; Verma, Aprajita; Hailey-Dunsheath, Steven; Menten, Karl M.; Güsten, Rolf; Weiß, Axel; Irwin, Kent; Cho, Hsiao M.; Niemack, Michael; Halpern, Mark; Amiri, Mandana; Hasselfield, Matthew; and others

    2014-01-10

    We recently commissioned our new spectrometer, the second-generation z(Redshift) and Early Universe Spectrometer (ZEUS-2) on the Atacama Pathfinder Experiment telescope. ZEUS-2 is a submillimeter grating spectrometer optimized for detecting the faint and broad lines from distant galaxies that are redshifted into the telluric windows from 200 to 850 ?m. It uses a focal plane array of transition-edge sensed bolometers, the first use of these arrays for astrophysical spectroscopy. ZEUS-2 promises to be an important tool for studying galaxies in the years to come because of its synergy with Atacama Large Millimeter Array and its capabilities in the short submillimeter windows that are unique in the post-Herschel era. Here, we report on our first detection of the [C II] 158 ?m line with ZEUS-2. We detect the line at z ? 1.8 from H-ATLAS J091043.1–000322 with a line flux of (6.44 ± 0.42) × 10{sup –18} W m{sup –2}. Combined with its far-IR luminosity and a new Herschel-PACS detection of the [O I] 63 ?m line, we model the line emission as coming from a photo-dissociation region with far-ultraviolet radiation field, G ? 2 × 10{sup 4} G {sub 0}, gas density, n ? 1 × 10{sup 3} cm{sup –3} and size between ?0.4 and 1 kpc. On the basis of this model, we conclude that H-ATLAS J091043.1–000322 is a high-redshift analog of a local ultra-luminous IR galaxy; i.e., it is likely the site of a compact starburst caused by a major merger. Further identification of these merging systems is important for constraining galaxy formation and evolution models.

  3. The Schmidt-Kennicutt Law of Matched-age Star-forming Regions; Pa? Observations of the Early-phase Interacting Galaxy Taffy I

    NASA Astrophysics Data System (ADS)

    Komugi, S.; Tateuchi, K.; Motohara, K.; Takagi, T.; Iono, D.; Kaneko, H.; Ueda, J.; Saitoh, T. R.; Kato, N.; Konishi, M.; Koshida, S.; Morokuma, T.; Takahashi, H.; Tanabé, T.; Yoshii, Y.

    2012-10-01

    In order to test a recent hypothesis that the dispersion in the Schmidt-Kennicutt law arises from variations in the evolutionary stage of star-forming molecular clouds, we compared molecular gas and recent star formation in an early-phase merger galaxy pair, Taffy I (UGC 12915/UGC 12914, VV 254) which went through a direct collision 20 Myr ago and whose star-forming regions are expected to have similar ages. Narrowband Pa? image is obtained using the ANIR near-infrared camera on the mini-TAO 1 m telescope. The image enables us to derive accurate star formation rates within the galaxy directly. The total star formation rate, 22.2 M ? yr-1, was found to be much higher than previous estimates. Ages of individual star-forming blobs estimated from equivalent widths indicate that most star-forming regions are ~7 Myr old, except for a giant H II region at the bridge which is much younger. Comparison between star formation rates and molecular gas masses for the regions with the same age exhibits a surprisingly tight correlation, a slope of unity, and star formation efficiencies comparable to those of starburst galaxies. These results suggest that Taffy I has just evolved into a starburst system after the collision, and the star-forming sites are at a similar stage in their evolution from natal molecular clouds except for the bridge region. The tight Schmidt-Kennicutt law supports the scenario that dispersion in the star formation law is in large part due to differences in evolutionary stage of star-forming regions.

  4. THE SCHMIDT-KENNICUTT LAW OF MATCHED-AGE STAR-FORMING REGIONS; Pa{alpha} OBSERVATIONS OF THE EARLY-PHASE INTERACTING GALAXY TAFFY I

    SciTech Connect

    Komugi, S.; Tateuchi, K.; Motohara, K.; Kato, N.; Konishi, M.; Koshida, S.; Morokuma, T.; Takahashi, H.; Tanabe, T.; Yoshii, Y.; Takagi, T.; Iono, D.; Kaneko, H.; Ueda, J.; Saitoh, T. R.

    2012-10-01

    In order to test a recent hypothesis that the dispersion in the Schmidt-Kennicutt law arises from variations in the evolutionary stage of star-forming molecular clouds, we compared molecular gas and recent star formation in an early-phase merger galaxy pair, Taffy I (UGC 12915/UGC 12914, VV 254) which went through a direct collision 20 Myr ago and whose star-forming regions are expected to have similar ages. Narrowband Pa{alpha} image is obtained using the ANIR near-infrared camera on the mini-TAO 1 m telescope. The image enables us to derive accurate star formation rates within the galaxy directly. The total star formation rate, 22.2 M{sub Sun} yr{sup -1}, was found to be much higher than previous estimates. Ages of individual star-forming blobs estimated from equivalent widths indicate that most star-forming regions are {approx}7 Myr old, except for a giant H II region at the bridge which is much younger. Comparison between star formation rates and molecular gas masses for the regions with the same age exhibits a surprisingly tight correlation, a slope of unity, and star formation efficiencies comparable to those of starburst galaxies. These results suggest that Taffy I has just evolved into a starburst system after the collision, and the star-forming sites are at a similar stage in their evolution from natal molecular clouds except for the bridge region. The tight Schmidt-Kennicutt law supports the scenario that dispersion in the star formation law is in large part due to differences in evolutionary stage of star-forming regions.

  5. Relationship between skin barrier function in early neonates and diaper dermatitis during the first month of life: a prospective observational study.

    PubMed

    Yonezawa, Kaori; Haruna, Megumi; Shiraishi, Mie; Matsuzaki, Masayo; Sanada, Hiromi

    2014-01-01

    Diaper dermatitis, a common skin problem in newborn infants, is characterized by poor functioning of the skin barrier. This study aimed to elucidate the relationship between skin barrier function in 4-day-old infants and the occurrence of diaper dermatitis during the first month of life. We recruited healthy Japanese infants born at 35 weeks of gestation or more. We measured indicators of skin barrier function, namely skin pH and transepidermal water loss, in 4-day-old infants on four places on the body. Individual characteristics were recorded from the infants' medical charts. The presence of diaper dermatitis was judged using the diaper rash and erythema scoring scale, which was based on daily recording of the infants' skin condition by their parents. The parents also filled out a questionnaire 1 month after birth regarding stool frequency and certain external factors. The association between diaper dermatitis and skin barrier function was assessed using multiple logistic regression analysis. The analysis included 88 infants. The incidence of diaper dermatitis was 25.0%. After adjusting for stool frequency for 1 month we noted that high pH on the inner arm skin in 4-day-old infants increased the risk of diaper dermatitis during the first month of life (adjusted odds ratio 3.35 [95% confidence interval = 1.12, 10.04]). Early neonatal skin pH may predict the risk of diaper dermatitis during the first month of life. Our results may be useful in devising strategies to prevent diaper dermatitis. PMID:25209731

  6. Observational Studies and a Statistical Early Warning of Surface Ozone Pollution in Tangshan, the Largest Heavy Industry City of North China

    PubMed Central

    Li, Pei; Xin, Jinyuan; Bai, Xiaoping; Wang, Yuesi; Wang, Shigong; Liu, Shixi; Feng, Xiaoxin

    2013-01-01

    Continuous measurements of surface ozone (O3) and nitrogen oxides (NOX) at an urban site (39°37?N, 118°09?E) in Tangshan, the largest heavy industry city of North China during summertime from 2008 to 2011 are presented. The pollution of O3 was serious in the city. The daily maximum 1 h means (O3_1-hr max) reached 157 ± 55, 161 ± 54, 120 ± 50, and 178 ± 75 ?g/m3 corresponding to an excess over the standard rates of 21%, 27%, 10%, and 40% in 2008–2011, respectively. The total oxidant level (OX = O3 + NO2) was high, with seasonal average concentrations up to 100 ?g/m3 in summer. The level of OX at a given location was made up of NOX-independent and NOX-dependent contributions. The independent part can be considered as a regional contribution and was about 100 ?g/m3 in Tangshan. Statistical early warning analysis revealed that the O3 levels would exceed the standard rate by 50% on the day following a day when the daily average ozone concentration (O3_mean) exceeded 87 ?g/m3 and the daily maximum temperature (T_max) exceeded 29 °C. The exceed-standard rate would reach 80% when O3_mean and T_max exceeded 113 ?g/m3 and 31 °C. Similarly, the exceed-standard rate would reach 100% when O3_mean and T_max exceeded 127 ?g/m3 and 33 °C, respectively. PMID:23485953

  7. A preliminary fMRI study of a novel self-paced written fluency task: observation of left-hemispheric activation, and increased frontal activation in late vs. early task phases

    PubMed Central

    Golestanirad, Laleh; Das, Sunit; Schweizer, Tom A.; Graham, Simon J.

    2015-01-01

    Neuropsychological tests of verbal fluency are very widely used to characterize impaired cognitive function. For clinical neuroscience studies and potential medical applications, measuring the brain activity that underlies such tests with functional magnetic resonance imaging (fMRI) is of significant interest—but a challenging proposition because overt speech can cause signal artifacts, which tend to worsen as the duration of speech tasks becomes longer. In a novel approach, we present the group brain activity of 12 subjects who performed a self-paced written version of phonemic fluency using fMRI-compatible tablet technology that recorded responses and provided task-related feedback on a projection screen display, over long-duration task blocks (60 s). As predicted, we observed robust activation in the left anterior inferior and medial frontal gyri, consistent with previously reported results of verbal fluency tasks which established the role of these areas in strategic word retrieval. In addition, the number of words produced in the late phase (last 30 s) of written phonemic fluency was significantly less (p < 0.05) than the number produced in the early phase (first 30 s). Activation during the late phase vs. the early phase was also assessed from the first 20 s and last 20 s of task performance, which eliminated the possibility that the sluggish hemodynamic response from the early phase would affect the activation estimates of the late phase. The last 20 s produced greater activation maps covering extended areas in bilateral precuneus, cuneus, middle temporal gyrus, insula, middle frontal gyrus and cingulate gyrus. Among these areas, greater activation was observed in the bilateral middle frontal gyrus (Brodmann area BA 9) and cingulate gyrus (BA 24, 32) likely as part of the initiation, maintenance, and shifting of attentional resources. Consistent with previous pertinent fMRI literature involving overt and covert verbal responses, these findings highlight the promise and practicality of fMRI of written phonemic fluency. PMID:25805984

  8. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2013-11-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Due to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult if not misleading. In this study we compared changes in peat decomposition in cores of two peat bogs (Königsmoor (KK), Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier Transform Infrared spectra absorption (FTIR) intensities, Rock Eval® oxygen- and hydrogen indices, ?13C and ?15N isotopic signatures and UV-absorption of NaOH peat extracts. In addition, one of the cores was analysed for changes in the peat's molecular composition using pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling process. Moreover, all decomposition proxies except UV-ABS and ?15N isotopes show similar patterns in their records and thus reflect in different extents signals of decomposition. Pyrolysis-GC-MS analyses of the KK core reveal that changes in peat molecular chemistry are mainly attributed to decomposition processes and to a lesser extend to changes in vegetation. Changes in the abundance of molecular compounds indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation, and presumably reflects changes in vegetation associated to changes in hydrology of the bogs. Significant correlations with polysaccharide and aliphatic pyrolysis products were found for C / N ratios, FTIR-band intensities and for hydrogen index values, supporting that these decomposition indices provide reasonable information despite their bulk nature. Correlation with oxygen index values and ?13C was weaker assumingly indicating carboxylation of the peat during drier periods and enrichment of isotopically lighter peat components during decomposition, respectively. FTIR, C / N ratio, Pyrolysis-GC-MS analyses and Rock Eval hydrogen indices appear to reflect mass loss and related changes in the molecular peat composition during mineralization best. Different to the other investigated proxies, Pyrolysis-GC-MS and FTIR analyses allow disentangling decomposition processes and vegetation changes. UV-ABS measurements of alkaline peat extracts show only weak correlation with other decomposition proxiesas they mainly reflect the formation of humic acids through humifcation and to a~lesser extend mass loss during mineralization.

  9. Determining the degree of peat decomposition - A comparison of different methods

    NASA Astrophysics Data System (ADS)

    Biester, Harald; Knorr, Klaus-Holger; Schellekens, Judith; Basler, Anna; Hermanns, Yvonne-Marie

    2014-05-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Due to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult if not misleading. In this study we compared changes in peat decomposition in cores of two peat bogs (Königsmoor (KK), Kleines Rotes Bruch (KRB)) from the Harz Mountains (Germany) using C/N ratios, Fourier Transform Infrared spectra absorption (FTIR) intensities, Rock Eval® oxygen- and hydrogen indices, ?13C and ?15N isotopic signatures and UV-absorption of NaOH peat extracts. In addition, one of the cores was analysed for changes in the peat's molecular composition using pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling process. Moreover, all decomposition proxies except UV-ABS and ?15N isotopes show similar patterns in their records and thus reflect in different extents signals of decomposition. Pyrolysis-GC-MS analyses of the KK core reveal that changes in peat molecular chemistry are mainly attributed to decomposition processes and to a lesser extend to changes in vegetation. Changes in the abundance of molecular compounds indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation, and presumably reflects changes in vegetation associated to changes in hydrology of the bogs. Significant correlations with polysaccharide and aliphatic pyrolysis products were found for C/N ratios, FTIR-band intensities and for hydrogen index values, supporting that these decomposition indices provide reasonable information despite their bulk nature. Correlation with oxygen index values and ?13C was lower assumingly indicating carboxylation of the peat during drier periods and enrichment of isotopically lighter peat components during decomposition, respectively. FTIR, C/N ratio, Pyrolysis-GC-MS analyses and Rock Eval hydrogen indices appear to reflect mass loss and related changes in the molecular peat composition during mineralization best. Different to the other investigated proxies, Pyrolysis-GC-MS and FTIR analyses allow disentangling decomposition processes and vegetation changes. UV-ABS measurements of alkaline peat extracts show only weak correlation with other decomposition proxies as they mainly reflect the formation of humic acids through humifcation and to a lesser extend mass loss during mineralization.

  10. Multilevel domain decomposition for electronic structure calculations

    SciTech Connect

    Barrault, M. . E-mail: maxime.barrault@edf.fr; Cances, E. . E-mail: cances@cermics.enpc.fr; Hager, W.W. . E-mail: hager@math.ufl.edu; Le Bris, C. . E-mail: lebris@cermics.enpc.fr

    2007-03-01

    We introduce a new multilevel domain decomposition method (MDD) for electronic structure calculations within semi-empirical and density functional theory (DFT) frameworks. This method iterates between local fine solvers and global coarse solvers, in the spirit of domain decomposition methods. Using this approach, calculations have been successfully performed on several linear polymer chains containing up to 40,000 atoms and 200,000 atomic orbitals. Both the computational cost and the memory requirement scale linearly with the number of atoms. Additional speed-up can easily be obtained by parallelization. We show that this domain decomposition method outperforms the density matrix minimization (DMM) method for poor initial guesses. Our method provides an efficient preconditioner for DMM and other linear scaling methods, variational in nature, such as the orbital minimization (OM) procedure.

  11. Isothermal Decomposition of Hydrogen Peroxide Dihydrate

    NASA Technical Reports Server (NTRS)

    Loeffler, M. J.; Baragiola, R. A.

    2011-01-01

    We present a new method of growing pure solid hydrogen peroxide in an ultra high vacuum environment and apply it to determine thermal stability of the dihydrate compound that forms when water and hydrogen peroxide are mixed at low temperatures. Using infrared spectroscopy and thermogravimetric analysis, we quantified the isothermal decomposition of the metastable dihydrate at 151.6 K. This decomposition occurs by fractional distillation through the preferential sublimation of water, which leads to the formation of pure hydrogen peroxide. The results imply that in an astronomical environment where condensed mixtures of H2O2 and H2O are shielded from radiolytic decomposition and warmed to temperatures where sublimation is significant, highly concentrated or even pure hydrogen peroxide may form.

  12. Error reduction in EMG signal decomposition

    PubMed Central

    Kline, Joshua C.

    2014-01-01

    Decomposition of the electromyographic (EMG) signal into constituent action potentials and the identification of individual firing instances of each motor unit in the presence of ambient noise are inherently probabilistic processes, whether performed manually or with automated algorithms. Consequently, they are subject to errors. We set out to classify and reduce these errors by analyzing 1,061 motor-unit action-potential trains (MUAPTs), obtained by decomposing surface EMG (sEMG) signals recorded during human voluntary contractions. Decomposition errors were classified into two general categories: location errors representing variability in the temporal localization of each motor-unit firing instance and identification errors consisting of falsely detected or missed firing instances. To mitigate these errors, we developed an error-reduction algorithm that combines multiple decomposition estimates to determine a more probable estimate of motor-unit firing instances with fewer errors. The performance of the algorithm is governed by a trade-off between the yield of MUAPTs obtained above a given accuracy level and the time required to perform the decomposition. When applied to a set of sEMG signals synthesized from real MUAPTs, the identification error was reduced by an average of 1.78%, improving the accuracy to 97.0%, and the location error was reduced by an average of 1.66 ms. The error-reduction algorithm in this study is not limited to any specific decomposition strategy. Rather, we propose it be used for other decomposition methods, especially when analyzing precise motor-unit firing instances, as occurs when measuring synchronization. PMID:25210159

  13. Priming of soil organic matter decomposition in cryoturbated Arctic soils

    NASA Astrophysics Data System (ADS)

    Richter, A.; Wild, B.; Schnecker, J.; Rusalimova, O.

    2012-12-01

    The Arctic is subjected to particularly high rates of warming, with profound consequences for the carbon cycle: on the one hand plant productivity and C storage in plant biomass have been shown to increase strongly in many parts of the Arctic, on the other hand, increasing rates of soil organic matter (SOM) decomposition have been reported. One of the possibilities that could reconcile these observations is, that increased plant growth may lead to increased root exudation rates, which are known to stimulate microbial turnover of organic matter under certain circumstances, in a process termed "priming" of SOM. Two mechanisms have been brought forward that may be responsible for priming: first, easily assimilable material exuded by plant roots may help microbes to overcome their energy limitation and second, this input of labile carbon could lead to a nitrogen limitation of the microbial community and lead to nitrogen mining, i.e. decomposition of N-rich SOM. We here report on an incubation study with arctic soil investigating potential priming of SOM decomposition in organic topsoil horizons, cryoturbated organic matter and subsoil mineral horizons of tundra soil from the Taymyr peninsula in Siberia. We used arctic soils, that are characterized by cryoturbation (mixing of soil layers due to freezing and thawing), for this study. Turbated cryosols store more than 580 Gt C globally, a significant proportion of which is stored in the cryoturbated organic matter. We hypothesized that an increased availability of labile compounds would increase SOM decomposition rates, and that this effect would be strongest in horizons with a low natural availability of labile C, i.e. in the mineral subsoil. We amended soils with 13C labelled glucose, cellulose, amino acids or proteins, and measured the mineralization of SOM C as well as microbial community composition and potential activities of extracellular enzymes. Our results demonstrate that topsoil organic, cryoturbated and subsoil mineral horizons responded differently to additions of labile compounds. In the mineral subsoil, all amended compounds increased the mineralization of SOM strongly (by a factor of 2 to 3), while in the organic topsoil, none of the amended compounds increased SOM mineralization. In cryoturbated horizons, SOM decomposition was increased by a factor of 2, but only when organic nitrogen (amino acids or protein) was added, but did not respond to additions of organic C only (glucose and cellulose). This may point to a severe nitrogen limitation of the microbial community in cryoturbated OM, in that only the addition of N allowed the production of enzymes for decomposition. Taken together, our results suggest that microbial activity in the mineral subsoil, but not in the organic topsoil, was limited in labile carbon. SOM in the mineral subsoil might thus be particularly vulnerable if the availability of labile compounds increases due to increased plant productivity. Microbial communities in cryoturbated horizons, in contrast, showed strong N limitation, suggesting that the decomposition of cryoturbated SOM might be susceptible to changes in soil N availability, especially if higher temperatures may lead to higher N mineralization rates.

  14. DEVELOPMENT OF A NOVEL CATALYST FOR NO DECOMPOSITION

    SciTech Connect

    Ates Akyurtlu; Jale F Akyurtlu

    2005-03-31

    Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NO{sub x} emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N{sub 2} will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation leads one to believe that the Pt/SnO{sub 2} catalysts may have a potential as NO decomposition catalysts in the presence of oxygen. This prediction is also supported by some preliminary data obtained for NO decomposition on a Pt/SnO{sub 2} catalyst in the PI's laboratory. The main objective of the proposed research is the evaluation of the Pt/SnO{sub 2} catalysts for the decomposition of NO in simulated power plant stack gases with particular attention to the resistance to deactivation by O{sub 2}, CO{sub 2}, and elevated temperatures. Therefore, it is proposed to perform temperature programmed desorption (TPD) and temperature programmed reaction (TPRx) studies on Pt/SnO{sub 2} catalysts having different noble metal concentrations and pretreated under different conditions. It is also proposed to perform NO decomposition tests in a laboratory-size packed-bed reactor to obtain long-term deactivation data. In the previous reporting period runs were made with feed gas mixtures containing water vapor. Two reaction regimes, one below and the other above 750 K were observed. Presence of water vapor slightly enhanced the catalyst activity, but decreased the selectivity towards N{sub 2} at low temperatures. For the current reporting period it was decided to Finish the runs with water vapor in the feed, check the effect of higher gas flow rate, and run experiments with catalyst treated at 900 K and 1000 K to drive off the OH groups. Unfortunately, shortly into the current period we had to change the gas feed preparation section. Then two flow controllers failed and we had to switch to rotameters and manual flow control as a stop gap measure. This affected the quality of the results and required repeated runs. Currently the results are satisfactory and the experiments are continuing. To take advantage of the down time the surface areas of the 15% Pt and 10% Pt catalysts were measured. The results indicate that when the catalysts are treated at 900 K for to hours to remove most of the OH groups on the surface, the activity of the 15% Pt catalyst increased.

  15. Predictions and observations of HF radio propagation in the northerly ionosphere: The effect of the solar flares and a weak CME in early January 2014.

    NASA Astrophysics Data System (ADS)

    Hallam, Jonathan; Stocker, Alan J.; Warrington, Mike; Siddle, Dave; Zaalov, Nikolay; Honary, Farideh; Rogers, Neil; Boteler, David; Danskin, Donald

    2014-05-01

    We have previously reported on a significant new multi-national project to provide improved predictions and forecasts of HF radio propagation for commercial aircraft operating on trans-polar routes. In these regions, there are limited or no VHF air-traffic control facilities and geostationary satellites are below the horizon. Therefore HF radio remains important in maintaining communications with the aircraft at all times. Space weather disturbances can have a range of effects on the ionosphere and hence HF radio propagation - particularly in the polar cap. While severe space weather effects can lead to a total loss of communications (i.e. radio blackout), less intense events can still cause significant disruption. In this paper we will present the effect of a series of M and X class solar flares and a relatively weak CME on HF radio performance from 6 to 13 January 2014. This is an interesting interval from the point of view of HF radio propagation because while the solar effects on the ionosphere are significant, except for an interval of approximately 12 hours duration, they are not so intense as to produce a complete radio blackout on all paths. Observations of the signal-to-noise ratio, direction of arrival, and time of flight of HF radio signals on six paths (one entirely within the polar cap, three trans-auroral, and two sub-auroral) will be presented together with riometer measurements of the ionospheric absorption. Global maps of D-region absorption (D-region absorption prediction, DRAP) inferred from satellite measurements of the solar wind parameters will be compared with the HF and riometer observations. In addition, a ray-tracing model using a realistic background ionosphere and including localised features found in the ionospheric polar cap (e.g. polar patches and arcs) will be used to model the expected and observed HF radio propagation characteristics.

  16. High temperature decomposition of hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2011-01-01

    Nitric oxide (NO) is oxidized into nitrogen dioxide (NO.sub.2) by the high temperature decomposition of a hydrogen peroxide solution to produce the oxidative free radicals, hydroxyl and hydroperoxyl. The hydrogen peroxide solution is impinged upon a heated surface in a stream of nitric oxide where it decomposes to produce the oxidative free radicals. Because the decomposition of the hydrogen peroxide solution occurs within the stream of the nitric oxide, rapid gas-phase oxidation of nitric oxide into nitrogen dioxide occurs.

  17. Angular momentum decomposition from a QED example

    E-print Network

    Tianbo Liu; Bo-Qiang Ma

    2014-12-25

    We investigate the angular momentum decomposition with a quantum electrodynamics example to clarify the proton spin decomposition debates. We adopt the light-front formalism where the parton model is well defined. We prove that the sum of fermion and boson angular momenta is equal to half the sum of the two gravitational form factors $A(0)$ and $B(0)$, as is well known. However, the suggestion to make a separation of the above relation into the fermion and boson pieces, as a way to measure the orbital angular momentum of fermions or bosons, respectively, is not justified from our explicit calculation.

  18. The formation and decomposition of firefly dioxetanone

    NASA Astrophysics Data System (ADS)

    Min, Chun-gang; Ren, Ai-min; Li, Xiao-na; Guo, Jing-fu; Zou, Lu-yi; Sun, Ying; Goddard, John D.; Sun, Chia-chung

    2011-04-01

    Firefly bioluminescence has attracted great attention for many years. Some details of the mechanism underlying firefly bioluminescence remain elusive. In this study the formation and decomposition reactions of firefly dioxetanone (DO) have been investigated in the gas phase and in a solvent model with an appropriate dielectric constant. Firefly DO is identified as a key intermediate. The formation of DO involves a stepwise reaction mechanism: first the formation of the four-membered ring on the singlet potential surface but not on the triplet and then the departure of the POCH32- group. For the decomposition of DO, two possible reaction paths are proposed, one of which is reported for the first time.

  19. Decomposition of any quantum measurement into extremals

    E-print Network

    G. Sentís; B. Gendra; S. D. Bartlett; A. C. Doherty

    2013-09-02

    We design an efficient and constructive algorithm to decompose any generalized quantum measurement into a convex combination of extremal measurements. We show that if one allows for a classical post-processing step only extremal rank-1 POVMs are needed. For a measurement with $N$ elements on a $d$-dimensional space, our algorithm will decompose it into at most $(N-1)d+1$ extremals, whereas the best previously known upper bound scaled as $d^2$. Since the decomposition is not unique, we show how to tailor our algorithm to provide particular types of decompositions that exhibit some desired property.

  20. High temperature decomposition of hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2004-01-01

    Nitric oxide (NO) is oxidized into nitrogen dioxide (NO.sub.2) by the high temperature decomposition of a hydrogen peroxide solution to produce the oxidative free radicals, hydroxyl and hydroperoxyl. The hydrogen peroxide solution is impinged upon a heated surface in a stream of nitric oxide where it decomposes to produce the oxidative free radicals. Because the decomposition of the hydrogen peroxide solution occurs within the stream of the nitric oxide, rapid gas-phase oxidation of nitric oxide into nitrogen dioxide occurs.

  1. Nucleon spin decomposition and differential geometry

    E-print Network

    Jordan François; Serge Lazzarini; Thierry Masson

    2015-02-20

    In the last few years, the so-called Chen et al. approach of the nucleon spin decomposition has been widely discussed and elaborated on. In this letter we propose a genuine differential geometric understanding of this approach. We mainly highligth its relation to the "dressing field method" we advocated in [C. Fournel, J. Fran\\c{c}ois, S. Lazzarini, T. Masson, Int. J. Geom. Methods Mod. Phys. 11, 1450016 (2014)]. We are led to the conclusion that the claimed gauge-invariance of the Chen et al. decomposition is actually unreal.

  2. Detritus Quality Controls Macrophyte Decomposition under Different Nutrient Concentrations in a Eutrophic Shallow Lake, North China

    PubMed Central

    Li, Xia; Cui, Baoshan; Yang, Qichun; Tian, Hanqin; Lan, Yan; Wang, Tingting; Han, Zhen

    2012-01-01

    Macrophyte decomposition is important for carbon and nutrient cycling in lake ecosystems. Currently, little is known about how this process responds to detritus quality and water nutrient conditions in eutrophic shallow lakes in which incomplete decomposition of detritus accelerates the lake terrestrialization process. In this study, we investigated the effects of detritus quality and water nutrient concentrations on macrophyte decomposition in Lake Baiyangdian, China, by analyzing the decomposition of three major aquatic plants at three sites with different pollution intensities (low, medium, and high pollution sites). Detritus quality refers to detritus nutrient contents as well as C?N, C?P, and N?P mass ratios in this study. Effects of detritus mixtures were tested by combining pairs of representative macrophytes at ratios of 75?25, 50?50 and 25?75 (mass basis). The results indicate that the influence of species types on decomposition was stronger than that of site conditions. Correlation analysis showed that mass losses at the end of the experimental period were significantly controlled by initial detritus chemistry, especially by the initial phosphorus (P) content, carbon to nitrogen (C?N), and carbon to phosphorus (C?P) mass ratios in the detritus. The decomposition processes were also influenced by water chemistry. The NO3-N and NH4-N concentrations in the lake water retarded detritus mass loss at the low and high pollution sites, respectively. Net P mineralization in detritus was observed at all sites and detritus P release at the high pollution site was slower than at the other two sites. Nonadditive effects of mixtures tended to be species specific due to the different nutrient contents in each species. Results suggest that the nonadditive effects varied significantly among different sites, indicating that interactions between the detritus quality in species mixtures and site water chemistry may be another driver controlling decomposition in eutrophic shallow lakes. PMID:22848699

  3. Canonical information flow decomposition among neural structure subsets

    PubMed Central

    Takahashi, Daniel Y.; Baccalá, Luiz A.; Sameshima, Koichi

    2014-01-01

    Partial directed coherence (PDC) and directed coherence (DC) which describe complementary aspects of the directed information flow between pairs of univariate components that belong to a vector of simultaneously observed time series have recently been generalized as bPDC/bDC, respectively, to portray the relationship between subsets of component vectors (Takahashi, 2009; Faes and Nollo, 2013). This generalization is specially important for neuroscience applications as one often wishes to address the link between the set of time series from an observed ROI (region of interest) with respect to series from some other physiologically relevant ROI. bPDC/bDC are limited, however, in that several time series within a given subset may be irrelevant or may even interact opposingly with respect to one another leading to interpretation difficulties. To address this, we propose an alternative measure, termed cPDC/cDC, employing canonical decomposition to reveal the main frequency domain modes of interaction between the vector subsets. We also show bPDC/bDC and cPDC/cDC are related and possess mutual information rate interpretations. Numerical examples and a real data set illustrate the concepts. The present contribution provides what is seemingly the first canonical decomposition of information flow in the frequency domain. PMID:24910609

  4. Decomposition of purine nucleobases by very low energy electrons

    NASA Astrophysics Data System (ADS)

    Abdoul-Carime, H.; Langer, J.; Huels, M. A.; Illenberger, E.

    2005-08-01

    We show that low energy electrons effectively decompose the gas phase purine nucleobases adenine (A) and guanine (G) via dissociative electron attachment (DEA) involving low lying (<3 eV) shape resonances, but also via core excited resonances (located near 6 eV). In adenine the low energy resonances exclusively lead to dehydrogenation, i.e. ejection of a neutral hydrogen radical with the excess electron remaining on the molecule. This reaction by far dominates DEA in the entire energy range 0 15 eV, similar to the situation recently observed in the pyrimidine bases thymine (T), cytosine (C) and uracil (U). In striking contrast to that, guanine behaves very different in that dehydrogenation is comparatively weak while various further decomposition reactions are observed from the low energy ? * precursor ions. These reactions lead to fragment ions of the form (G O/NH{2})^-, O^-/NH{2}^-, (G HOCN)^-, OCN^-, CN- indicative of single bond cleavages but also more complex unimolecular decompositions associated with the excision of cyano units from the cyclic structure. Since electrons are the predominant secondary species in the interaction of high energy quanta with biological material, electron driven reactions represent initial steps in the molecular description of radiation damage.

  5. Thermal decomposition of energetic materials 29 - The fast thermal decomposition characteristics of a multicomponent material

    SciTech Connect

    Cronin, J.T.; Brill, T.B. )

    1988-10-01

    The high-rate (>100/sup 0/C sec/sup -1/) decomposition characteristics of a multicomponent liquid gun propellant containing hydroxylammonium nitrate (HAN), triethanol ammonium nitrate (TEAN), and water are described with the rapid-scan FTIR thermal profiling technique. The decomposition characteristics of the HAN and TEAN components were examined and then compared to the pyrolysis behavior of the liquid gun propellant 1845 (LGP1854). A four-step process that describes the major events occurring during the fast thermal decomposition and ignition of LGP1845 is presented.

  6. Explaining the reportedly over-massive black holes in early-type galaxies with intermediate-scale discs

    E-print Network

    Savorgnan, Giulia A D

    2015-01-01

    The classification "early-type" galaxy includes both elliptically- and lenticular-shaped galaxies. Theoretically, the spheroid-to-disc flux ratio of an early-type galaxy can assume any positive value, but in practice studies often consider only spheroid/disc decompositions in which the disc neatly dominates over the spheroid at large galaxy radii, creating an inner "bulge" as observed in most spiral galaxies. Here we show that decompositions in which the disc remains embedded within the spheroid, labelled by some as "unphysical", correctly reproduce both the photometric and kinematic properties of early-type galaxies with intermediate-scale discs. Intermediate-scale discs have often been confused with large-scale discs and incorrectly modelled as such; when this happens, the spheroid luminosity is considerably underestimated. This has recently led to some surprising conclusions, such as the claim that a number of galaxies with intermediate-scale discs (Mrk 1216, NGC 1277, NGC 1271, and NGC 1332) host a centra...

  7. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    NASA Astrophysics Data System (ADS)

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-10-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11?litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species.

  8. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    PubMed Central

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-01-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11?litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species. PMID:26515033

  9. Keratin subsidies promote feather decomposition via an increase in keratin-consuming arthropods and microorganisms in bird breeding colonies.

    PubMed

    Sugiura, Shinji; Masuya, Hayato

    2015-06-01

    Resource subsidies are well known to increase population densities of consumers. The decomposition process of these subsidised resources can be influenced by increasing consumer abundance. However, few studies have assessed whether resource subsidies can promote resource decomposition via a population increase in consumers. Here, we examined the effects of keratin subsidies on feather decomposition in egret and heron breeding colonies. Egrets and herons (Ardeidae) frequently breed in inland forests and provide large amounts of keratin materials to the forest floor in the form of feathers of chicks (that die). We compared the decrease in the weights of egret and heron feathers (experimentally placed on the forest floor) over a 12-month period among egret/heron breeding colonies (five sites) and areas outside of colonies (five sites) in central Japan. Of the feathers placed experimentally on forest floors, 92-97 % and 99-100 % in colonies and 47-50 % and 71-90 % in non-colony areas were decomposed after 4 and 12 months, respectively. Then, decomposition rates of feathers were faster in colonies than in areas outside of colonies, suggesting that keratin subsidies can promote feather decomposition in colonies. Field observations and laboratory experiments indicated that keratin-feeding arthropods and keratinophilic fungi played important roles in feather decomposition. Therefore, scavenging arthropods and keratinophilic fungi, which dramatically increased in egret and heron breeding colonies, could accelerate the decomposition of feathers supplied to the forest floor of colonies. PMID:25903424

  10. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition.

    PubMed

    Li, Yongfu; Chen, Na; Harmon, Mark E; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A; Mao, Jingdong

    2015-01-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11?litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced (13)C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species. PMID:26515033

  11. Keratin subsidies promote feather decomposition via an increase in keratin-consuming arthropods and microorganisms in bird breeding colonies

    NASA Astrophysics Data System (ADS)

    Sugiura, Shinji; Masuya, Hayato

    2015-06-01

    Resource subsidies are well known to increase population densities of consumers. The decomposition process of these subsidised resources can be influenced by increasing consumer abundance. However, few studies have assessed whether resource subsidies can promote resource decomposition via a population increase in consumers. Here, we examined the effects of keratin subsidies on feather decomposition in egret and heron breeding colonies. Egrets and herons (Ardeidae) frequently breed in inland forests and provide large amounts of keratin materials to the forest floor in the form of feathers of chicks (that die). We compared the decrease in the weights of egret and heron feathers (experimentally placed on the forest floor) over a 12-month period among egret/heron breeding colonies (five sites) and areas outside of colonies (five sites) in central Japan. Of the feathers placed experimentally on forest floors, 92-97 % and 99-100 % in colonies and 47-50 % and 71-90 % in non-colony areas were decomposed after 4 and 12 months, respectively. Then, decomposition rates of feathers were faster in colonies than in areas outside of colonies, suggesting that keratin subsidies can promote feather decomposition in colonies. Field observations and laboratory experiments indicated that keratin-feeding arthropods and keratinophilic fungi played important roles in feather decomposition. Therefore, scavenging arthropods and keratinophilic fungi, which dramatically increased in egret and heron breeding colonies, could accelerate the decomposition of feathers supplied to the forest floor of colonies.

  12. Natural Decompositions of Perceived Transparency: Reply to Albert (2008) Barton L. Anderson

    E-print Network

    Singh, Manish

    2008-01-01

    Natural Decompositions of Perceived Transparency: Reply to Albert (2008) Barton L. Anderson proposed a model based on ratios of Michelson contrasts to explain how human observers quantitatively scale general model based on ratios of perceived contrasts. M. K. Albert's (2008) main experiment aimed to test

  13. gamma-Irradiation effects on the thermal decomposition behaviour and IR absorption spectra of piperacillin

    NASA Astrophysics Data System (ADS)

    Mahfouz, R. M.; Gaffar, M. A.; Abu El-Fadl, A.; Hamad, Ar. G. K.

    2003-11-01

    The thermal decomposition behaviour of unirradiated and pre-gamma-irradiated piperacillin (pipril) as a semi-synthetic penicillin antibiotic has been studied in the temperature range of (273-1072 K). The decomposition was found to proceed through three major steps both for unirradiated and gamma-irradiated samples. Neither appearance nor disappearance of new bands in the IR spectrum of piperacillin was recorded as a result of gamma-irradiation but only a decrease in the intensity of most bands was observed. A degradation mechanism was suggested to explain the bond rupture and the decrease in the intensities of IR bands of gamma-irradiated piperacillin.

  14. TRIANGLE-SHAPED DC CORONA DISCHARGE DEVICE FOR MOLECULAR DECOMPOSITION

    EPA Science Inventory

    The paper discusses the evaluation of electrostatic DC corona discharge devices for the application of molecular decomposition. A point-to-plane geometry corona device with a rectangular cross section demonstrated low decomposition efficiencies in earlier experimental work. The n...

  15. Simplicial Decomposition with Disaggregated Representation for the Traffic Assignment

    E-print Network

    Patriksson, Michael

    Simplicial Decomposition with Disaggregated Representation for the Traffic Assignment Problem network flows. When applied to the traffic assignment problem, shortest route subproblems are solved decomposition and the closely related column generation methods for the traffic assignment problem; we

  16. Are there infinitely many decompositions of the nucleon spin ?

    E-print Network

    Masashi Wakamatsu

    2013-08-01

    We argue against the rapidly spreading idea of gauge-invariant-extension (GIE) approach in the nucleon spin decomposition problem, which implies the existence of infinitely many gauge-invariant decomposition of the nucleon spin.

  17. DEVELOPMENT OF A NOVEL CATALYST FOR NO DECOMPOSITION

    SciTech Connect

    Ates Akyurtlu; Jale F. Akyurtlu

    2005-06-27

    Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NO{sub x} emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N{sub 2} will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation leads one to believe that the Pt/SnO{sub 2} catalysts may have a potential as NO decomposition catalysts in the presence of oxygen. This prediction is also supported by some preliminary data obtained for NO decomposition on a Pt/SnO{sub 2} catalyst in the PI's laboratory. The main objective of the proposed research is the evaluation of the Pt/SnO{sub 2} catalysts for the decomposition of NO in simulated power plant stack gases with particular attention to the resistance to deactivation by O{sub 2}, CO{sub 2}, and elevated temperatures. Therefore, it is proposed to perform temperature programmed desorption (TPD) and temperature programmed reaction (TPRx) studies on Pt/SnO{sub 2} catalysts having different noble metal concentrations and pretreated under different conditions. It is also proposed to perform NO decomposition tests in a laboratory-size packed-bed reactor to obtain long-term deactivation data. In the previous reporting period the GC-MS system was calibrated and the TPD runs for the 15% Pt/SnO{sub 2} catalyst after treatment with NO and subsequent treatments with NO and O{sub 2} were done. For these runs the catalyst was pretreated with dry helium for 2 hours at 40 C. The Temperature Programmed Reaction (TPRx) of NO and NO+O{sub 2} mixtures on the catalysts containing 15% Pt and 10% Pt were also performed. In this reporting period some TPRx runs with the catalysts containing 15% and 10% Pt were repeated due to the uncertainty of the oxygen content of the feed.

  18. Ascomycota Members Dominate Fungal Communities during Straw Residue Decomposition in Arable Soil

    PubMed Central

    Ma, Anzhou; Zhuang, Xuliang; Wu, Junmei; Cui, Mengmeng; Lv, Di; Liu, Chunzhao; Zhuang, Guoqiang

    2013-01-01

    This study investigated the development of fungal community composition in arable soil during the degradation of straw residue. We explored the short-term responses of the fungal community over 28 days of decomposition in soil using culture-independent polymerase chain reaction in combination with a clone library and denaturing gradient gel electrophoresis (DGGE). Fungal cellobiohydrolase I (cbhI) genes in the soil were also characterized, and their diversity suggested the existence of a different cellulose decomposer. The DGGE profiles based on fungal internal transcribed spacer analysis showed different successions of fungal populations during residue decomposition. Members of Lecythophora and Sordariales were dominant in the early succession, while Hypocrea and Engyodontium were better adapted in the late succession. The succession of fungal communities might be related to changes of residue quality during decomposition. Collectively, sequences assigned to Ascomycota members were dominant at different stages of the fungal succession during decomposition, revealing that they were key drivers responsible for residue degradation in the arable soil tested. PMID:23840414

  19. CaII K interstellar observations towards early-type disc and halo stars - distances to intermediate- and high-velocity clouds

    NASA Astrophysics Data System (ADS)

    Smoker, J. V.; Lynn, B. B.; Rolleston, W. R. J.; Kay, H. R. M.; Bajaja, E.; Poppel, W. G. L.; Keenan, F. P.; Kalberla, P. M. W.; Mooney, C. J.; Dufton, P. L.; Ryans, R. S. I.

    2004-08-01

    We compare existing high spectral resolution (R=?/??~ 40000) CaII K observations (?air= 3933.66 Å) towards 88 mainly B-type stars, and new observations taken using the Intermediate dispersion Spectrograph and Imaging System (ISIS) on the William Herschel Telescope at R~ 10000 towards three stars taken from the Palomar-Green Survey, with 21-cm HI emission-line profiles, in order to search for optical absorption towards known intermediate- and high-velocity cloud complexes. Given certain assumptions, limits to the gas phase abundance of CaII are estimated for the cloud components. We use the data to derive the following distances from the Galactic plane (z). (i) Tentative lower z-height limits of 2800 and 4100 pc towards complex C using lack of absorption in the spectra of HD341617 and PG0855+294, respectively. (ii) A weak lower z-height of 1400 pc towards complex WA-WB using lack of absorption in EC09470-1433 and a weak lower limit of 2470 pc using lack of absorption in EC09452-1403. (iii) An upper z-height of 2470 pc towards a southern intermediate-velocity cloud (IVC) with vLSR=-55 km s-1 using PG2351+198. (iv) Detection of a possible IVC in CaII absorption at vLSR=+52 km s-1 using EC20104-2944. No associated HI in emission is detected. At this position, normal Galactic rotation predicts velocities of up to ~+25 km s-1. The detection puts an upper z-height of 1860 pc to the cloud. (v) Tentative HI and CaII K detections towards an IVC at ~+70 km s-1 in the direction of high-velocity cloud (HVC) complex WE, sightline EC06387-8045, indicating that the IVC may be at a z-height lower than 1770 pc. (vi) Detection of CaII K absorption in the spectrum of PG0855+294 in the direction of IV20, indicating that this IVC has a z-height smaller than 4100 pc. (vii) A weak lower z-height of 4300 pc towards a small HVC with vLSR=+115 km s-1 at l, b= 200°, + 52°, using lack of absorption in the CaII K spectrum of PG0955+291.

  20. Nitrogen Amendment Stimulated Decomposition of Maize Straw-Derived Biochar in a Sandy Loam Soil: A Short-Term Study

    PubMed Central

    Lu, Weiwei; Ding, Weixin; Zhang, Junhua; Zhang, Huanjun; Luo, Jiafa; Bolan, Nanthi

    2015-01-01

    This study examined the effect of nitrogen (N) on biochar stability in relation to soil microbial community as well as biochar labile components using ?13C stable isotope technology. A sandy loam soil under a long-term rotation of C3 crops was amended with biochar produced from maize (a C4 plant) straw in absence (BC0) and presence (BCN) of N and monitored for dynamics of carbon dioxide (CO2) flux, phospholipid fatty acids (PLFAs) profile and dissolved organic carbon (DOC) content. N amendment significantly increased the decomposition of biochar during the first 5 days of incubation (P < 0.05), and the proportions of decomposed biochar carbon (C) were 2.30% and 3.28% in BC0 and BCN treatments, respectively, during 30 days of incubation. The magnitude of decomposed biochar C was significantly (P < 0.05) higher than DOC in biochar (1.75%) and part of relatively recalcitrant biochar C was mineralized in both treatments. N amendment increased soil PLFAs concentration at the beginning of incubation, indicating that microorganisms were N-limited in test soil. Furthermore, N amendment significantly (P < 0.05) increased the proportion of gram-positive (G+) bacteria and decreased that of fungi, while no noticeable changes were observed for gram-negative (G?) bacteria and actinobacteria at the early stage of incubation. Our results indicated that N amendment promoted more efficiently the proliferation of G+ bacteria and accelerated the decomposition of relatively recalcitrant biochar C, which in turn reduced the stability of maize straw-derived biochar in test soil. PMID:26192282