Science.gov

Sample records for detailed abundance analysis

  1. Detailed abundance analysis of five field blue horizontal-branch stars

    NASA Astrophysics Data System (ADS)

    Kafando, I.; LeBlanc, F.; Robert, C.

    2016-06-01

    Previous studies have shown that hot blue horizontal-branch (BHB) stars in globular clusters present abundance anomalies of certain chemical elements in their atmosphere; some metals are overabundant while helium is underabundant. Vertical stratification of chemical species, including iron, is also found in the atmosphere of a number of these objects. The aim of our work is to do a detailed abundance analysis of BHB stars found in the field. We studied the stars HD 128801, HD 143459, HD 213781, and HZ 27, using our high-resolution spectra in the visible region obtained with ESPaDOnS at the Canada-France-Hawaii Telescope, and also Feige 86, using existing Ultraviolet and Visual Echelle Spectrograph visible spectra from the ESO archives. We searched for vertical stratification of the elements identified in our five stars, with the ZEEMAN2 code and stellar model atmospheres of PHOENIX. We confirm here the star rotational and radial velocities previously found, along with their average abundances. For the three cooler stars in our sample (HD 128801, HD 143459, and HZ 27), most elements detected are underabundant. For the two hotter stars (Feige 86 and HD 213781), the abundances of most elements are near or above their solar value. Of all the elements studied, only phosphorus is clearly found to be vertically stratified in the atmosphere of HD 213781. Marginal indications of vertical stratification of iron is observed for Feige 86. The chemical properties of the five field BHB stars are consistent with those of their globular-cluster counterparts.

  2. Detailed abundance analysis of the brightest star in Segue 2, the least massive galaxy

    NASA Astrophysics Data System (ADS)

    Roederer, Ian U.; Kirby, Evan N.

    2014-05-01

    We present the first high-resolution spectroscopic observations of one red giant star in the ultra-faint dwarf galaxy Segue 2, which has the lowest total mass (including dark matter) estimated for any known galaxy. These observations were made using the Magellan Inamori Kyocera Echelle (MIKE) spectrograph on the Magellan II Telescope at Las Campanas Observatory. We perform a standard abundance analysis of this star, SDSS J021933.13+200830.2, and present abundances of 21 species of 18 elements as well as upper limits for 25 additional species. We derive [Fe/H] = -2.9, in excellent agreement with previous estimates from medium-resolution spectroscopy. Our main result is that this star bears the chemical signatures commonly found in field stars of similar metallicity. The heavy elements produced by neutron-capture reactions are present, but they are deficient at levels characteristic of stars in other ultra-faint dwarf galaxies and a few luminous dwarf galaxies. The otherwise normal abundance patterns suggest that the gas from which this star formed was enriched by metals from multiple Type II supernovae reflecting a relatively well-sampled IMF. This adds to the growing body of evidence indicating that Segue 2 may have been substantially more massive in the past.

  3. MyGIsFOS: an automated code for parameter determination and detailed abundance analysis in cool stars

    NASA Astrophysics Data System (ADS)

    Sbordone, L.; Caffau, E.; Bonifacio, P.; Duffau, S.

    2014-04-01

    Context. The current and planned high-resolution, high-multiplexity stellar spectroscopic surveys, as well as the swelling amount of underutilized data present in public archives, have led to an increasing number of efforts to automate the crucial but slow process of retrieving stellar parameters and chemical abundances from spectra. Aims: We present MyGIsFOS1, a code designed to derive atmospheric parameters and detailed stellar abundances from medium- to high-resolution spectra of cool (FGK) stars. We describe the general structure and workings of the code, present analyses of a number of well-studied stars representative of the parameter space MyGIsFOS is designed to cover, and give examples of the exploitation of MyGIsFOS very fast analysis to assess uncertainties through Monte Carlo tests. Methods: MyGIsFOS aims to reproduce a "traditional" manual analysis by fitting spectral features for different elements against a precomputed grid of synthetic spectra. The lines of Fe i and Fe ii can be employed to determine temperature, gravity, microturbulence, and metallicity by iteratively minimizing the dependence of Fe i abundance from line lower energy and equivalent width, and imposing Fe i-Fe ii ionization equilibrium. Once parameters are retrieved, detailed chemical abundances are measured from lines of other elements. Results: MyGIsFOS replicates closely the results obtained in similar analyses on a set of well-known stars. It is also quite fast, performing a full parameter determination and detailed abundance analysis in about two minutes per star on a mainstream desktop computer. Currently, its preferred field of application are high-resolution and/or large spectral coverage data (e.g., UVES, X-shooter, HARPS, Sophie). My God It's Full Of Stars, http://mygisfos.obspm.fr

  4. Preliminary Results of Detailed Chemical Abundance Analysis of Milky Way Satellite Galaxy Reticulum II Discovered in the Dark Energy Survey

    NASA Astrophysics Data System (ADS)

    Nagasawa, Daniel; Marshall, Jennifer L.; Li, Ting; Dark Energy Survey Milky Way Science Group

    2016-01-01

    We present preliminary results from abundance analysis of stars in Milky Way satellite galaxies found in the Dark Energy Survey (DES). DES has discovered 16 candidate satellite galaxies of the Milky Way in its first two years of operation. Since January 2015, three candidates have subsequently been revealed to be dark matter-dominated by spectroscopic follow-up studies of their kinematics, confirming their status as satellite galaxies. Spectroscopic follow-up of the remaining 13 candidates is underway. We have analyzed high resolution VLT/GIRAFFE spectra of member stars in one of these satellite galaxies, Reticulum II. Using equivalent width measurement and spectral synthesis methods, we measure the abundances of Iron and other species in order to begin to understand the chemical content of these Milky Way satellites.

  5. Detailed Chemical Abundances of Planet-Hosting Wide Binary Systems

    NASA Astrophysics Data System (ADS)

    Mack, Claude E.; Schuler, Simon C.; Stassun, Keivan; Pepper, Joshua

    2015-01-01

    We present a detailed chemical abundance analysis of planet-hosting wide binary systems. Each of these binary systems consists of two stars with similar spectral types (ranging from G2V - K2V), and in each system, at least one star hosts a giant planet with an orbital pericenter ~< 0.5 AU. We investigate if giant planets on such orbits could have scattered inner rocky planets into the atmospheres of their host stars, and thereby imprint a detectable chemical signature in the stellar photospheric abundances. Using high-resolution, high signal-to-noise echelle spectra, we derive the chemical abundances ([X/H]) of 15 elements covering a range of condensation temperatures (Tc). For stars in our sample with approximately solar metallicity, the refractory elements (Tc > 900 K) show a positive correlation between [X/H] and Tc. However, for stars with super-solar metallicities, the refractory elements show a negative correlation between [X/H] and Tc. We interpret these results in the context of numerical simulations of giant planet migration that predict the accretion of hydrogen-depleted rocky material by the host star. We demonstrate that a simple model for a solar-metallicity star accreting material with Earth-like composition predicts a positive correlation between [X/H] and Tc, while for a supersolar-metallicity star the model predicts a negative correlation. The stark contrast between the predicted correlations for solar-metallicity and supersolar-metallicity stars may indicate that extracting any chemical signature of rocky planetary accretion is particularly challenging for very metal-rich stars.

  6. Detailed Chemical Abundances of Planet-Hosting Wide Binary Systems

    NASA Astrophysics Data System (ADS)

    Mack, Claude Ernest; Schuler, Simon; Stassun, Keivan

    2015-08-01

    We present a detailed chemical abundance analysis of planet-hosting wide binary systems. Each of these binary systems consists of two stars with similar spectral types (ranging from G2V - K2V), and in each system, at least one star hosts a giant planet with an orbital pericenter ~< 0.5 AU. We examine the photospheric abundances of the host stars to determine if they have ingested rocky planetary material as a result of the close-in giant planets scattering inner rocky planets into the star as they migrated to their present-day locations. Using high-resolution, high signal-to-noise echelle spectra, for both stars in each system we derive the chemical abundances ([X/H]) of 15 elements covering a range of condensation temperatures (Tc). For stars in our sample with approximately solar metallicity, the refractory elements (Tc > 900 K) show a positive correlation between [X/H] and Tc. However, for stars with super-solar metallicities, the refractory elements show a negative correlation between [X/H] and Tc. We interpret these results in the context of numerical simulations of giant planet migration that predict the accretion of hydrogen-depleted rocky material by the host star. We demonstrate that a simple model for a solar-metallicity star accreting material with Earth-like composition predicts a positive correlation between [X/H] and Tc, while for a supersolar-metallicity star the model predicts a negative correlation. The stark contrast between the predicted correlations for solar-metallicity and supersolar-metallicity stars may indicate that extracting any chemical signature of rocky planetary accretion is particularly challenging for very metal-rich stars.

  7. Detailed Abundances of Stars with Small Planets Discovered by Kepler

    NASA Astrophysics Data System (ADS)

    Schuler, Simon C.; Vaz, Zachary A.; Katime Santrich, Orlando J.; Cunha, Katia M. L.; Smith, Verne V.; King, Jeremy R.; Ghezzi, Luan; Howell, Steve B.; Teske, Johanna

    2016-01-01

    We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star save one has at least one planet with a radius less than 2 REarth, suggesting a primarily rocky composition. The stellar parameters and abundances are derived from high signal-to-noise ratio, high-resolution echelle spectroscopy obtained with the 10-m Keck I telescope and HIRES spectrometer using standard spectroscopic techniques. We compare the abundances to those of a general Galactic disk population and investigate possible abundance trends with condensation temperature of the elements.S.C.S. acknowledges support provided by grant NNX12AD19G to S.C.S. from the National Aeronautics and Space Administration as part of the Kepler Participating Scientist Program.

  8. Investigating Detailed Abundance Patterns in the Hyades Cluster

    NASA Astrophysics Data System (ADS)

    Williams, Drake; Schuler, Simon C.

    2016-01-01

    We have derived the paramters and abundances of up to 17 elements for seven stars within the Hyades open star cluster, through an analysis of high-resolution, high signal-to-noise ratio spectra obtained via the Harlan J. Smith 2.7 m telescope and the 2dcoude cross-dispersed echelle spectrometer at the McDonald Observatory. Four of the stars are solar-type dwarves while three giants were also analyzed to better calculate an overall metallicity of the entire cluster. In addition, we investigated whether there are differences in various stellar abundance trends across the open cluster. Here we present the results of our abundance analysis and stellar parameter derivations of the seven stars and discuss the implications of stellar abundance patterns across star clusters. We acknowledge support provided by grant NNX12AD19G to S.C.S. from the National Aeronautics and Space Administration as part of the Kepler Participating Scientist Program.

  9. A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars

    SciTech Connect

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Burley, Gregory S.; Kelson, Daniel D.; Sneden, Christopher

    2014-06-01

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ≈0.25 dex for red giants and ≈0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] ≤–3.5, 84 stars with [Fe/H] ≤–3.0, and 210 stars with [Fe/H] ≤–2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] ≤–2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.

  10. The Hamburg/ESO R-process enhanced star survey (HERES). IV. Detailed abundance analysis and age dating of the strongly r-process enhanced stars CS 29491-069 and HE 1219-0312

    NASA Astrophysics Data System (ADS)

    Hayek, W.; Wiesendahl, U.; Christlieb, N.; Eriksson, K.; Korn, A. J.; Barklem, P. S.; Hill, V.; Beers, T. C.; Farouqi, K.; Pfeiffer, B.; Kratz, K.-L.

    2009-09-01

    We report on a detailed abundance analysis of two strongly r-process enhanced, very metal-poor stars newly discovered in the HERES project, CS 29491-069 ([Fe/H]=-2.51, [r/Fe]=+1.1) and HE 1219-0312 ([Fe/H]=-2.96, [r/Fe]=+1.5). The analysis is based on high-quality VLT/UVES spectra and MARCS model atmospheres. We detect lines of 15 heavy elements in the spectrum of CS 29491-069, and 18 in HE 1219-0312; in both cases including the Th II 4019 Å line. The heavy-element abundance patterns of these two stars are mostly well-matched to scaled solar residual abundances not formed by the s-process. We also compare the observed pattern with recent high-entropy wind (HEW) calculations, which assume core-collapse supernovae of massive stars as the astrophysical environment for the r-process, and find good agreement for most lanthanides. The abundance ratios of the lighter elements strontium, yttrium, and zirconium, which are presumably not formed by the main r-process, are reproduced well by the model. Radioactive dating for CS 29491-069 with the observed thorium and rare-earth element abundance pairs results in an average age of 9.5 Gyr, when based on solar r-process residuals, and 17.6 Gyr, when using HEW model predictions. Chronometry seems to fail in the case of HE 1219-0312, resulting in a negative age due to its high thorium abundance. HE 1219-0312 could therefore exhibit an overabundance of the heaviest elements, which is sometimes called an “actinide boost”. Based on observations collected at the European Southern Observatory, Paranal, Chile (Proposal Number 170.D-0010). Table 8 is only available in electronic form at http://www.aanda.org

  11. A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-poor Stars

    NASA Astrophysics Data System (ADS)

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Sneden, Christopher; Burley, Gregory S.; Kelson, Daniel D.

    2014-06-01

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ≈0.25 dex for red giants and ≈0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] <=-3.5, 84 stars with [Fe/H] <=-3.0, and 210 stars with [Fe/H] <=-2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] <=-2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile, and The McDonald Observatory of The University of Texas at Austin. The Hobby-Eberly Telescope is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University

  12. Detailed chemical abundances of extragalactic globular clusters using high resolution, integrated light spectra

    NASA Astrophysics Data System (ADS)

    Colucci, Janet E.

    Globular clusters (GCs) are luminous, observationally accessible objects that are good tracers of the total star formation and evolutionary history of galaxies. We present the first detailed chemical abundances for GCs in M31 using a new abundance analysis technique designed for high resolution, integrated light (IL) spectra of GCs. This technique has recently been developed using a training set of old GCS in the Milky Way (MW), and makes possible detailed chemical evolution studies of distant galaxies, where high resolution abundance analysis of individual stars are not obtainable. For the 5 M31 GCs presented here, we measure abundances of 14 elements: Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Y, and Ba. We find the M31 GCs have ages (>10 Gyr) and chemical properties similar to MW GCs, including an enhancement in the alpha-elements Ca, Ti and Si of [alpha/Fe]˜ +0.4. In this thesis, we also further develop this IL abundance analysis method to include GCs of ages 10 Myr--12 Gyrs using GCs in the Large Magellanic Cloud (LMC), which contains the necessary sample of clusters over this wide age range. This work demonstrates for the first time that this IL abundance analysis method can be used on clusters of all ages, and that ages can be constrained to within 1--2 Gyr for clusters with ages of ˜2 Gyr and within a few 100 Myr for clusters with ages <1 Gyr. We find that we can measure [Fe/H] in clusters with ages <12 Gyrs with similar or only slightly larger uncertainties (0.1--0.25 dex) than those obtained for old GCs; the slightly larger uncertainties are due to the rapid evolution in stellar populations at these ages. Using the LMC clusters, we also investigate the effects of statistical fluctuations in the theoretical cluster stellar populations used in our analysis. We also develop strategies to allow for statistical variations in these stellar populations, and find that the stability of the Fe line abundance solution can provide tight constraints on the

  13. Detailed Abundances of Planet-hosting Wide Binaries. II. HD80606+HD80607

    NASA Astrophysics Data System (ADS)

    Mack, Claude E., III; Stassun, Keivan G.; Schuler, Simon C.; Hebb, Leslie; Pepper, Joshua A.

    2016-02-01

    We present a detailed chemical abundance analysis of 15 elements in the planet-hosting wide binary (PHWB) system HD 80606+HD 80607 using Keck/HIRES spectra. As in our previous analysis of the PHWB HD 20782+HD 20781, we presume that these two G5 dwarf stars formed together and therefore had identical primordial abundances. In this binary, HD 80606 hosts an eccentric (e≈ 0.93) giant planet at ∼0.5 AU, but HD 80607 has no detected planets. If close-in giant planets on eccentric orbits are efficient at scattering rocky planetary material into their host stars, then HD 80606 should show evidence of having accreted rocky material while HD 80607 should not. Here we show that the trends of abundance versus element condensation temperature for HD 80606 and HD 80607 are statistically indistinguishable, corroborating the recent result of Saffe et al. This could suggest that both stars accreted similar amounts of rocky material; indeed, our model for the chemical signature of rocky planet accretion indicates that HD 80606 could have accreted up to 2.5 {M}\\oplus of rocky material—about half that contained in the Solar System and primordial asteroid belt—relative to HD 80607 and still be consistent with the data. Since HD 80607 has no known giant planets that might have pushed rocky planet material via migration onto that star, we consider it more likely that HD 80606/07 experienced essentially no rocky planet accretion. This in turn suggests that the migration history of the HD 80606 giant planet must have been such that it ejected any close-in planetary material that might have otherwise been shepherded onto the star.

  14. Constraining Planet Formation Theories with the Detailed Chemical Abundances of Planet-Hosting Wide Binary Stars

    NASA Astrophysics Data System (ADS)

    Mack, Claude Ernest; Schuler, Simon; Stassun, Keivan

    2015-12-01

    We present a detailed chemical abundance analysis of planet-hosting wide binary systems. Each of these binary systems consists of two stars with similar spectral types (ranging from G2V - K2V), and in each system, at least one star hosts a giant planet with an orbital pericenter ~< 0.5 AU. We examine the photospheric abundances of the host stars to determine if they have ingested rocky planetary material as a result of the close-in giant planets scattering inner rocky planets into the star as they migrated to their present-day locations. Using high-resolution, high signal-to-noise echelle spectra, for both stars in each system we derive the chemical abundances ([X/H]) of 15 elements covering a range of condensation temperatures (Tc). For stars in our sample with approximately solar metallicity, the refractory elements (Tc > 900 K) show a positive correlation between [X/H] and Tc. However, for stars with super-solar metallicities, the refractory elements show a slightly negative correlation between [X/H] and Tc. We interpret these results in the context of numerical simulations of giant planet migration that predict the accretion of hydrogen-depleted rocky material by the host star. We demonstrate that a simple model for a solar-metallicity star accreting material with Earth-like composition predicts a positive correlation between [X/H] and Tc, while for a supersolar-metallicity star the model predicts a negative correlation. The stark contrast between the predicted correlations for solar-metallicity and supersolar-metallicity stars may indicate that extracting any chemical signature of rocky planetary accretion is particularly challenging for very metal-rich stars.

  15. Detailed fuel spray analysis techniques

    NASA Technical Reports Server (NTRS)

    Mularz, E. J.; Bosque, M. A.; Humenik, F. M.

    1983-01-01

    Detailed fuel spray analyses are a necessary input to the analytical modeling of the complex mixing and combustion processes which occur in advanced combustor systems. It is anticipated that by controlling fuel-air reaction conditions, combustor temperatures can be better controlled, leading to improved combustion system durability. Thus, a research program is underway to demonstrate the capability to measure liquid droplet size, velocity, and number density throughout a fuel spray and to utilize this measurement technique in laboratory benchmark experiments. The research activities from two contracts and one grant are described with results to data. The experiment to characterize fuel sprays is also described. These experiments and data should be useful for application to and validation of turbulent flow modeling to improve the design systems of future advanced technology engines.

  16. Detailed chemical abundances of distant RR Lyrae stars in the Virgo Stellar Stream

    NASA Astrophysics Data System (ADS)

    Duffau, S.; Sbordone, L.; Vivas, A. K.; Hansen, C. J.; Zoccali, M.; Catelan, M.; Minniti, D.; Grebel, E. K.

    2016-05-01

    We present the first detailed chemical abundances for distant RR Lyrae stars members of the Virgo Stellar Stream (VSS), derived from X- Shooter medium-resolution spectra. Sixteen elements from carbon to barium have been measured in six VSS RR Lyrae stars, sampling all main nucleosynthetic channels. For the first time we will be able to compare in detail the chemical evolution of the VSS progenitor with those of Local Group dwarf spheroidal galaxies (LG dSph) as well as the one of the smooth halo.

  17. A Comparison of the Detailed Chemical Abundances of Globular Clusters in the Milky Way, Andromeda, and Centaurus A Galaxies

    NASA Astrophysics Data System (ADS)

    Colucci, Janet E.; Bernstein, Rebecca

    2016-01-01

    We present a homogeneous analysis of high resolution spectra of globular clusters in three massive galaxies: the Milky Way, M31, and NGC 5128. We measure detailed abundance ratios for alpha, light, Fe-peak, and neutron capture elements using our technique for analyzing the integrated light spectra of globular clusters. For many of the heavy elements we provide a first look at the detailed chemistry of old populations in an early type galaxy. We discuss similarities and differences between the galaxies and the potential implications for their star formation histories.

  18. A Detailed Study of the Elemental Abundances of Metal-Weak Thick Disk Stars

    NASA Astrophysics Data System (ADS)

    Simmerer, J.

    2004-12-01

    Studies of the existing stellar components of the Galaxy offer a fossil record of its formation history. Of the various populations (bulge, halo, thin disk,and thick disk), the thick disk in particular is still difficult to characterize. Although the metallicity distributions of the two Galactic populations overlap, thick disk stars appear to be much older than thin disk stars, as they are enhanced in alpha-capture and rapid process neutron-capture elements relative to thin disk stars. Recent studies have also indicated that the thick disk includes stars as metal-poor as [Fe/H]=-2.2, well into the ``pure halo'' metallicity regime. Explanations for the origin of this metal-weak thick disk (MWTD) invoke either a long formation time scale (essentially coeval with the halo) or suggest the capture of dwarf galaxies, from which low-metallicity stars have been subsumed. In order to help distinguish between formation scenarios, high-resolution, high-S/N spectra of a large sample of MWTD stars identified by Chiba & Beers (2000) and Beers et al. (2002) have been gathered and analyzed. These objects are kinematically associated with the thick disk, but are far more iron-poor than previously studied thick-disk stars. A detailed abundance analysis will confirm whether these stars are truly metal-poor, and whether they are chemically related to the halo, the canonical thick disk, the thin disk, or none of these. This work has been supported in part by NSF grant AST 03-07495.

  19. Detailed chemical abundances in NGC 5824: another metal-poor globular cluster with internal heavy element abundance variations

    NASA Astrophysics Data System (ADS)

    Roederer, Ian U.; Mateo, Mario; Bailey, John I.; Spencer, Meghin; Crane, Jeffrey D.; Shectman, Stephen A.

    2016-01-01

    We present radial velocities, stellar parameters, and detailed abundances of 39 elements derived from high-resolution spectroscopic observations of red giant stars in the luminous, metal-poor globular cluster NGC 5824. We observe 26 stars in NGC 5824 using the Michigan/Magellan Fiber System (M2FS) and two stars using the Magellan Inamori Kyocera Echelle spectrograph. We derive a mean metallicity of [Fe/H] = -1.94 ± 0.02 (statistical) ±0.10 (systematic). The metallicity dispersion of this sample of stars, 0.08 dex, is in agreement with previous work and does not exceed the expected observational errors. Previous work suggested an internal metallicity spread only when fainter samples of stars were considered, so we cannot exclude the possibility of an intrinsic metallicity dispersion in NGC 5824. The M2FS spectra reveal a large internal dispersion in [Mg/Fe], 0.28 dex, which is found in a few other luminous, metal-poor clusters. [Mg/Fe] is correlated with [O/Fe] and anticorrelated with [Na/Fe] and [Al/Fe]. There is no evidence for internal dispersion among the other α- or Fe-group abundance ratios. 25 of the 26 stars exhibit a n-capture enrichment pattern dominated by r-process nucleosynthesis (<[Eu/Fe]> = +0.11 ± 0.12; <[Ba/Eu]> = -0.66 ± 0.05). Only one star shows evidence of substantial s-process enhancement ([Ba/Fe] = +0.56 ± 0.12; [Ba/Eu] = +0.38 ± 0.14), but this star does not exhibit other characteristics associated with s-process enhancement via mass transfer from a binary companion. The Pb and other heavy elements produced by the s-process suggest a time-scale of no more than a few hundred Myr for star formation and chemical enrichment, like the complex globular clusters M2, M22, and NGC 5286.

  20. Detailed Abundances of Stars with Small Planets Discovered by Kepler. I. The First Sample

    NASA Astrophysics Data System (ADS)

    Schuler, Simon C.; Vaz, Zachary A.; Katime Santrich, Orlando J.; Cunha, Katia; Smith, Verne V.; King, Jeremy R.; Teske, Johanna K.; Ghezzi, Luan; Howell, Steve B.; Isaacson, Howard

    2015-12-01

    We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star, save one, has at least one planet with a radius ≤1.6 R⊕, suggesting a primarily rocky composition. The stellar parameters and abundances are derived from high signal-to-noise ratio, high-resolution echelle spectroscopy obtained with the 10 m Keck I telescope and High Resolution Echelle Spectrometer using standard spectroscopic techniques. The metallicities of the seven stars range from -0.32 to +0.13 dex, with an average metallicity that is subsolar, supporting previous suggestions that, unlike Jupiter-type giant planets, small planets do not form preferentially around metal-rich stars. The abundances of elements other than iron are in line with a population of Galactic disk stars, and despite our modest sample size, we find hints that the compositions of stars with small planets are similar to stars without known planets and with Neptune-size planets, but not to those of stars with giant planets. This suggests that the formation of small planets does not require exceptional host-star compositions and that small planets may be ubiquitous in the Galaxy. We compare our derived abundances (which have typical uncertainties of ≲0.04 dex) to the condensation temperature of the elements; a correlation between the two has been suggested as a possible signature of rocky planet formation. None of the stars demonstrate the putative rocky planet signature, despite at least three of the stars having rocky planets estimated to contain enough refractory material to produce the signature, if real. More detailed abundance analyses of stars known to host small planets are needed to verify our results and place ever more stringent constraints on planet formation models. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California

  1. Detailed Abundances of Two Very Metal-poor Stars in Dwarf Galaxies

    NASA Astrophysics Data System (ADS)

    Kirby, Evan N.; Cohen, Judith G.

    2012-12-01

    The most metal-poor stars in dwarf spheroidal galaxies (dSphs) can show the nucleosynthetic patterns of one or a few supernovae (SNe). These SNe could have zero metallicity, making metal-poor dSph stars the closest surviving links to Population III stars. Metal-poor dSph stars also help to reveal the formation mechanism of the Milky Way (MW) halo. We present the detailed abundances from Keck/HIRES spectroscopy for two very metal-poor stars in two MW dSphs. One star, in the Sculptor dSph, has [Fe I/H] = -2.40. The other star, in the Ursa Minor dSph, has [Fe I/H] = -3.16. Both stars fall in the previously discovered low-metallicity, high-[α/Fe] plateau. Most abundance ratios of very metal-poor stars in these two dSphs are largely consistent with very metal-poor halo stars. However, the abundances of Na and some r-process elements lie at the lower end of the envelope defined by inner halo stars of similar metallicity. We propose that the metallicity dependence of SN yields is the cause. The earliest SNe in low-mass dSphs have less gas to pollute than the earliest SNe in massive halo progenitors. As a result, dSph stars at -3 < [Fe/H] < -2 sample SNe with [Fe/H] Lt -3, whereas halo stars in the same metallicity range sample SNe with [Fe/H] ~ -3. Consequently, enhancements in [Na/Fe] and [r/Fe] were deferred to higher metallicity in dSphs than in the progenitors of the inner halo. Data herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  2. DETAILED ABUNDANCES OF TWO VERY METAL-POOR STARS IN DWARF GALAXIES

    SciTech Connect

    Kirby, Evan N.; Cohen, Judith G.

    2012-12-01

    The most metal-poor stars in dwarf spheroidal galaxies (dSphs) can show the nucleosynthetic patterns of one or a few supernovae (SNe). These SNe could have zero metallicity, making metal-poor dSph stars the closest surviving links to Population III stars. Metal-poor dSph stars also help to reveal the formation mechanism of the Milky Way (MW) halo. We present the detailed abundances from Keck/HIRES spectroscopy for two very metal-poor stars in two MW dSphs. One star, in the Sculptor dSph, has [Fe I/H] = -2.40. The other star, in the Ursa Minor dSph, has [Fe I/H] = -3.16. Both stars fall in the previously discovered low-metallicity, high-[{alpha}/Fe] plateau. Most abundance ratios of very metal-poor stars in these two dSphs are largely consistent with very metal-poor halo stars. However, the abundances of Na and some r-process elements lie at the lower end of the envelope defined by inner halo stars of similar metallicity. We propose that the metallicity dependence of SN yields is the cause. The earliest SNe in low-mass dSphs have less gas to pollute than the earliest SNe in massive halo progenitors. As a result, dSph stars at -3 < [Fe/H] < -2 sample SNe with [Fe/H] << -3, whereas halo stars in the same metallicity range sample SNe with [Fe/H] {approx} -3. Consequently, enhancements in [Na/Fe] and [r/Fe] were deferred to higher metallicity in dSphs than in the progenitors of the inner halo.

  3. Detailed Chemical Abundances in the r-process-rich Ultra-faint Dwarf Galaxy Reticulum 2

    NASA Astrophysics Data System (ADS)

    Roederer, Ian U.; Mateo, Mario; Bailey, John I., III; Song, Yingyi; Bell, Eric F.; Crane, Jeffrey D.; Loebman, Sarah; Nidever, David L.; Olszewski, Edward W.; Shectman, Stephen A.; Thompson, Ian B.; Valluri, Monica; Walker, Matthew G.

    2016-03-01

    The ultra-faint dwarf (UFD) galaxy Reticulum 2 (Ret 2) was recently discovered in images obtained by the Dark Energy Survey. We have observed the four brightest red giants in Ret 2 at high spectral resolution using the Michigan/Magellan Fiber System. We present detailed abundances for as many as 20 elements per star, including 12 elements heavier than the Fe group. We confirm previous detection of high levels of r-process material in Ret 2 (mean [Eu/Fe] = +1.69 ± 0.05) found in three of these stars (mean [Fe/H] = -2.88 ± 0.10). The abundances closely match the r-process pattern found in the well-studied metal-poor halo star CS 22892-052. Such r-process-enhanced stars have not been found in any other UFD galaxy, though their existence has been predicted by at least one model. The fourth star in Ret 2 ([Fe/H] = -3.42 ± 0.20) contains only trace amounts of Sr ([Sr/Fe] = -1.73 ± 0.43) and no detectable heavier elements. One r-process enhanced star is also enhanced in C (natal [C/Fe] ≈ +1.1). This is only the third such star known, which suggests that the nucleosynthesis sites leading to C and r-process enhancements are decoupled. The r-process-deficient star is enhanced in Mg ([Mg/Fe] = +0.81 ± 0.14), and the other three stars show normal levels of α-enhancement (mean [Mg/Fe] = +0.34 ± 0.03). The abundances of other α and Fe-group elements closely resemble those in UFD galaxies and metal-poor halo stars, suggesting that the nucleosynthesis that led to the large r-process enhancements either produced no light elements or produced light-element abundance signatures indistinguishable from normal supernovae. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  4. Chemical abundance analysis of 19 barium stars

    NASA Astrophysics Data System (ADS)

    Yang, Guo-Chao; Liang, Yan-Chun; Spite, Monique; Chen, Yu-Qin; Zhao, Gang; Zhang, Bo; Liu, Guo-Qing; Liu, Yu-Juan; Liu, Nian; Deng, Li-Cai; Spite, Francois; Hill, Vanessa; Zhang, Cai-Xia

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures Teff, surface gravities log g, metallicity [Fe/H] and microturbulence velocity ξt) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants as indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their Na, Al, α- and iron-peak elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-capture) process elements relative to the Sun. Their median abundances of [Ba/Fe], [La/Fe] and [Eu/Fe] are 0.54, 0.65 and 0.40, respectively. The Y I and Zr I abundances are lower than Ba, La and Eu, but higher than the α- and iron-peak elements for the strong Ba stars and similar to the iron-peak elements for the mild stars. There exists a positive correlation between Ba intensity and [Ba/Fe]. For the n-capture elements (Y, Zr, Ba, La), there is an anti-correlation between their [X/Fe] and [Fe/H]. We identify nine of our sample stars as strong Ba stars with [Ba/Fe] >0.6 where seven of them have Ba intensity Ba=2-5, one has Ba=1.5 and another one has Ba=1.0. The remaining ten stars are classified as mild Ba stars with 0.17<[Ba/Fe] <0.54.

  5. Global detailed geoid computation and model analysis

    NASA Technical Reports Server (NTRS)

    Marsh, J. G.; Vincent, S.

    1974-01-01

    Comparisons and analyses were carried out through the use of detailed gravimetric geoids which we have computed by combining models with a set of 26,000 1 deg x 1 deg mean free air gravity anomalies. The accuracy of the detailed gravimetric geoid computed using the most recent Goddard earth model (GEM-6) in conjunction with the set of 1 deg x 1 deg mean free air gravity anomalies is assessed at + or - 2 meters on the continents of North America, Europe, and Australia, 2 to 5 meters in the Northeast Pacific and North Atlantic areas, and 5 to 10 meters in other areas where surface gravity data are sparse. The R.M.S. differences between this detailed geoid and the detailed geoids computed using the other satellite gravity fields in conjuction with same set of surface data range from 3 to 7 meters.

  6. Abundance analysis of s-process enhanced barium stars

    NASA Astrophysics Data System (ADS)

    Mahanta, Upakul; Karinkuzhi, Drisya; Goswami, Aruna; Duorah, Kalpana

    2016-08-01

    Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the Galactic chemical enrichment. We present abundance results from high-resolution spectral analyses of a sample of four chemically peculiar stars characterized by s-process enhancement. High-Resolution spectra (R ˜42000) of these objects spanning a wavelength range from 4000 to 6800 Å, are taken from the ELODIE archive. We have estimated the stellar atmospheric parameters, the effective temperature Teff, the surface gravity log g, and metallicity [Fe/H] from local thermodynamic equilibrium analysis using model atmospheres. We report estimates of elemental abundances for several neutron-capture elements, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu and Dy. While HD 49641 and HD 58368 show [Ba/Fe] ≥ 1.16 the other two objects HD 119650 and HD 191010 are found to be mild barium stars with [Ba/Fe] ˜ 0.4. The derived abundances of the elements are interpreted on the basis of existing theories for understanding their origin and evolution.

  7. On the nature of sn stars. I. A detailed abundance study

    NASA Astrophysics Data System (ADS)

    Saffe, C.; Levato, H.

    2014-02-01

    The sn stars were first discoved by Abt & Levato when studying the spectral types in different open clusters. These stars present sharp Balmer lines, sharp metallic lines (C II, Si II, Ca II, Ti II, Fe II), and broad coreless He I lines. Some of the sn stars seem to be related to CP stars. Initially Abt & Levato proposed a shell-like nature to explain the sn stars, although this scenario was subsequently questioned. There is no general agreement about their origin. We aim to derive abundances for a sample of 9 stars, including sn and non-sn stars, to determine the possible relation between sn and CP stars and compare their chemical abundances. That most sn stars belong to open clusters allows us to search for a possible relation with fundamental parameters, including the age and rotation. We also study the possible contribution of different effects to the broad He I lines observed in these stars, such as Stark broadening and the possible He-stratification. Effective temperature and gravity were estimated by Strömgren photometry and then refined by requiring ionization and excitation equilibrium of Fe lines. We derived the abundances by fitting the observed spectra with synthetic spectra using an iterative procedure with the SYNTHE and ATLAS9 codes. We derived metallic abundances of 23 different chemical elements for 9 stars and obtained low projected rotational velocities for the sn stars in our sample (vsini up to 69 km s-1). We also compared 5 stars that belong to the same cluster (NGC 6475) and show that the sn characteristics appear in the 3 stars with the lower rotational velocity. However, the apparent preference of sn stars for objects with the lower vsini values should be taken with caution due to the small number of objects studied here. We analysed the photospheric chemical composition of sn stars and show that approximately ~40% of them display chemical peculiarities (such as He-weak and HgMn stars) within a range of temperature of 10 300 K-14 500 K

  8. THE STELLAR HALOS OF MASSIVE ELLIPTICAL GALAXIES. II. DETAILED ABUNDANCE RATIOS AT LARGE RADIUS

    SciTech Connect

    Greene, Jenny E.; Murphy, Jeremy D.; Graves, Genevieve J.; Gunn, James E.; Raskutti, Sudhir; Comerford, Julia M.; Gebhardt, Karl

    2013-10-20

    We study the radial dependence in stellar populations of 33 nearby early-type galaxies with central stellar velocity dispersions σ{sub *} ∼> 150 km s{sup –1}. We measure stellar population properties in composite spectra, and use ratios of these composites to highlight the largest spectral changes as a function of radius. Based on stellar population modeling, the typical star at 2R{sub e} is old (∼10 Gyr), relatively metal-poor ([Fe/H] ≈ –0.5), and α-enhanced ([Mg/Fe] ≈ 0.3). The stars were made rapidly at z ≈ 1.5-2 in shallow potential wells. Declining radial gradients in [C/Fe], which follow [Fe/H], also arise from rapid star formation timescales due to declining carbon yields from low-metallicity massive stars. In contrast, [N/Fe] remains high at large radius. Stars at large radius have different abundance ratio patterns from stars in the center of any present-day galaxy, but are similar to average Milky Way thick disk stars. Our observations are thus consistent with a picture in which the stellar outskirts are built up through minor mergers with disky galaxies whose star formation is truncated early (z ≈ 1.5-2)

  9. CD -24°17504: A New Comprehensive Element Abundance Analysis

    NASA Astrophysics Data System (ADS)

    Jacobson, Heather R.; Frebel, Anna

    2015-07-01

    With [Fe/H] ˜ -3.3, CD -24°17504 is a canonical metal-poor main-sequence turn-off star. Though it has appeared in numerous literature studies, the most comprehensive abundance analysis for the star based on high-resolution, high signal-to-noise ratio (S/N) spectra is nearly 15 years old. We present a new detailed abundance analysis for 21 elements based on combined archival Keck-HIRES and Very Large Telescope-UVES spectra of the star that is higher in both spectral resolution and S/N than previous data. Our results are very similar to those of an earlier comprehensive study of the star, but we present for the first time a carbon abundance from the CH G-band feature as well as improved upper limits for neutron-capture species such as Y, Ba, and Eu. In particular, we find that CD -24°17504 has [Fe/H] = -3.41, [C/Fe] = +1.10, [Sr/H] = -4.68, and [Ba/H] ≤ -4.46, making it a carbon-enhanced metal-poor star with neutron-capture element abundances among the lowest measured in Milky Way halo stars. This work is based on data obtained from the ESO Science Archive Facility and associated with Programs 68.D-0094(A) and 073.D-0024(A). This work is also based on data obtained from the Keck Observatory Archive (KOA), which is operated by the W.M. Keck Obsevatory and the NASA Exoplanet Science Institute (NExScI), under contract with the National Aeronautics and Space Administration. These data are associated with Program C01H (P.I. Mélendez).

  10. Detailed homogeneous abundance studies of 14 Galactic s-process enriched post-AGB stars: In search of lead (Pb)

    NASA Astrophysics Data System (ADS)

    De Smedt, K.; Van Winckel, H.; Kamath, D.; Siess, L.; Goriely, S.; Karakas, A. I.; Manick, R.

    2016-03-01

    Context. This paper is part of a larger project in which we systematically study the chemical abundances of Galactic and extragalactic post-asymptotic giant branch (post-AGB) stars. The goal at large is to provide improved observational constraints to the models of the complex interplay between the AGB s-process nucleosynthesis and the associated mixing processes. Aims: Lead (Pb) is the final product of the s-process nucleosynthesis and is predicted to have large overabundances with respect to other s-process elements in AGB stars of low metallicities. However, Pb abundance studies of s-process enriched post-AGB stars in the Magellanic Clouds show a discrepancy between observed and predicted Pb abundances. The determined upper limits based on spectral studies are much lower than what is predicted. In this paper, we focus specifically on the Pb abundance of 14 Galactic s-process enhanced post-AGB stars to check whether the same discrepancy is present in the Galaxy as well. Among these 14 objects, two were not yet subject to a detailed abundance study in the literature. We apply the same method to obtain accurate abundances for the 12 others. Our homogeneous abundance results provide the input of detailed spectral synthesis computations in the spectral regions where Pb lines are located. Methods: We used high-resolution UVES and HERMES spectra for detailed spectral abundance studies of our sample of Galactic post-AGB stars. None of the sample stars display clear Pb lines, and we only deduced upper limits of the Pb abundance by using spectrum synthesis in the spectral ranges of the strongest Pb lines. Results: We do not find any clear evidence of Pb overabundances in our sample. The derived upper limits are strongly correlated with the effective temperature of the stars with increasing upper limits for increasing effective temperatures. We obtain stronger Pb constraints on the cooler objects. Moreover, we confirm the s-process enrichment and carbon enhancement of two

  11. Detailed homogeneous abundance studies of 14 Galactic s-process enriched post-AGB stars: In search of lead (Pb)

    NASA Astrophysics Data System (ADS)

    De Smedt, K.; Van Winckel, H.; Kamath, D.; Siess, L.; Goriely, S.; Karakas, A. I.; Manick, R.

    2016-03-01

    Context. This paper is part of a larger project in which we systematically study the chemical abundances of Galactic and extragalactic post-asymptotic giant branch (post-AGB) stars. The goal at large is to provide improved observational constraints to the models of the complex interplay between the AGB s-process nucleosynthesis and the associated mixing processes. Aims: Lead (Pb) is the final product of the s-process nucleosynthesis and is predicted to have large overabundances with respect to other s-process elements in AGB stars of low metallicities. However, Pb abundance studies of s-process enriched post-AGB stars in the Magellanic Clouds show a discrepancy between observed and predicted Pb abundances. The determined upper limits based on spectral studies are much lower than what is predicted. In this paper, we focus specifically on the Pb abundance of 14 Galactic s-process enhanced post-AGB stars to check whether the same discrepancy is present in the Galaxy as well. Among these 14 objects, two were not yet subject to a detailed abundance study in the literature. We apply the same method to obtain accurate abundances for the 12 others. Our homogeneous abundance results provide the input of detailed spectral synthesis computations in the spectral regions where Pb lines are located. Methods: We used high-resolution UVES and HERMES spectra for detailed spectral abundance studies of our sample of Galactic post-AGB stars. None of the sample stars display clear Pb lines, and we only deduced upper limits of the Pb abundance by using spectrum synthesis in the spectral ranges of the strongest Pb lines. Results: We do not find any clear evidence of Pb overabundances in our sample. The derived upper limits are strongly correlated with the effective temperature of the stars with increasing upper limits for increasing effective temperatures. We obtain stronger Pb constraints on the cooler objects. Moreover, we confirm the s-process enrichment and carbon enhancement of two

  12. Detailed Abundances of a Planet-Hosting Wide Binary System: DidPlanet Formation Imprint Chemical Signatures in the Atmospheres ofHD20782/81?

    NASA Astrophysics Data System (ADS)

    Mack, Claude E.; Stassun, Keivan; Schuler, Simon C.; Norris, John E.

    2014-06-01

    We present a detailed chemical abundance analysis of a planet-hosting wide binary system (HD20782 + HD20781), where both stars are G-dwarfs, and each of them hosts giant planets on eccentric orbits with pericenters ~< 0.2 AU. We investigate if giant planets on such orbits could scatter inner rocky planets into the atmospheres of their host stars, and thereby imprint a detectable chemical signature in the stellar photospheric abundances. Using high-resolution, high signal-to-noise echelle spectra, we derive the abundances of 15 elements. In addition, the refractory elements (Tc > 900 K) in both stars show a positive correlation between the elemental abundances and condensation temperatures (Tc), with similar slopes of ~1×10-4 dex K-1. In each star, the measured positive correlations are imperfect, with a scatter of ~5×10-5 dex K-1 about the mean trend; also, certain elements (Na, Al, Sc) are similarly deviant in both stars. We interpret these results in the context of simulations of giant planet migration that predict the accretion of H-depleted rocky material by the host star. We demonstrate that a simple model for a solar-type star accreting material with Earth-like composition predicts a positive -- but imperfect -- correlation between [X/H] and Tc. According to this model, our measured slopes are consistent with the ingestion of 10-20 Earths by both HD20782 and HD20781.

  13. Detailed Abundances of a Planet-Hosting Wide Binary System: Did Planet Formation Imprint Chemical Signatures in the Atmospheres of HD20782/81?

    NASA Astrophysics Data System (ADS)

    Mack, C.

    2014-04-01

    We present a detailed chemical abundance analysis of a planet-hosting wide binary system (HD20782 + HD20781), where both stars are G-dwarfs, and each of them hosts giant planets on eccentric orbits with pericenters ~< 0.2 AU. We investigate if giant planets on such orbits could scatter inner rocky planets into the atmospheres of their host stars, and thereby imprint a detectable chemical signature in the stellar photospheric abundances. Using high-resolution, high signal-to-noise echelle spectra, we derive the abundances of 15 elements. In addition, the refractory elements (Tc > 900 K) in both stars show a positive correlation between the elemental abundances and condensation temperatures (Tc), with similar slopes of ~1x10^(-4) dex K^(-1). In each star, the measured positive correlations are imperfect, with a scatter of ~5x10^(-5) dex K^(-1) about the mean trend; also, certain elements (Na, Al, Sc) are similarly deviant in both stars. We interpret these results in the context of simulations of giant planet migration that predict the accretion of H-depleted rocky material by the host star. We demonstrate that a simple model for a solar-type star accreting material with Earth-like composition predicts a positive -- but imperfect -- correlation between [X/H] and Tc. According to this model, our measured slopes are consistent with the ingestion of 10-20 Earths by both HD20782 and HD20781.

  14. High-resolution abundance analysis of HD 140283

    NASA Astrophysics Data System (ADS)

    Siqueira-Mello, C.; Andrievsky, S. M.; Barbuy, B.; Spite, M.; Spite, F.; Korotin, S. A.

    2015-12-01

    Context. HD 140283 is a reference subgiant that is metal poor and confirmed to be a very old star. The element abundances of this type of old star can constrain the nature and nucleosynthesis processes that occurred in its (even older) progenitors. The present study may shed light on nucleosynthesis processes yielding heavy elements early in the Galaxy. Aims: A detailed analysis of a high-quality spectrum is carried out, with the intent of providing a reference on stellar lines and abundances of a very old, metal-poor subgiant. We aim to derive abundances from most available and measurable spectral lines. Methods: The analysis is carried out using high-resolution (R = 81 000) and high signal-to-noise ratio (800 analysis in non-LTE (NLTE) is based on the MULTI code. We present LTE abundances for 26 elements, and NLTE calculations for the species C i, O i, Na i, Mg i, Al i, K i, Ca i, Sr ii, and Ba ii lines. Results: The abundance analysis provided an extensive line list suitable for metal-poor subgiant stars. The results for Li, CNO, α-, and iron peak elements are in good agreement with literature. The newly NLTE Ba abundance, along with a NLTE Eu correction and a 3D Ba correction from literature, leads to [Eu/Ba] = + 0.59 ± 0.18. This result confirms a dominant r-process contribution, possibly together with a very small contribution from the main s-process, to the neutron-capture elements in HD 140283. Overabundances of the lighter heavy elements and the high abundances derived for Ba, La, and Ce favour the operation of the weak r-process in HD 140283

  15. Abundance analysis of extremely metal-poor stars

    NASA Astrophysics Data System (ADS)

    Hansen, T.; Hansen, C. J.; Christlieb, N.; Andersen, J.

    2016-01-01

    The outer atmosphere of the first generations of low-mass (M < 0.8 M⊙) stars retain to a great extent the original chemical composition of the interstellar medium (ISM) at the time and place of their birth. The composition of this pristine gas represents the nucleosynthesis of the very first massive stars, that produced and ejected the first heavy elements into the early ISM. Thus a detailed abundance analysis of low-mass, metal-poor stars can help us track these gasses and provide insight into the formation processes that took place in the very early stages of our Galaxy. Preliminary result of a 25-star homogeneously analysed sample of metal- poor candidates from the Hamburg/ESO survey is presented. The main focus is on the most metal-poor stars of the sample; stars with [Fe/H] < -4. The abundance pattern of these ultra metal-poor (UMP) stars is used to extract key information of the earliest ongoing formation processes (ranging from hydrostatic burning to neutron-capture processes).

  16. Detailed analysis of the promoter activity of an attenuated lentivirus.

    PubMed

    Blatti-Cardinaux, Laure; Sanjosé, Leticia; Zahno, Marie-Luise; Zanoni, Reto; Reina, Ramses; Bertoni, Giuseppe

    2016-07-01

    In spite of an eradication campaign that eliminated clinical cases of caprine arthritis encephalitis virus-induced arthritis in the Swiss goat population, seroconversions are still observed. In the affected flocks, viruses belonging mainly to the small ruminant lentivirus A4 subtype are regularly isolated. These viruses are considered attenuated, except in the mammary gland, where high viral loads and histopathological lesions have been observed. We previously characterized and sequenced such field isolates, detecting several potentially attenuating mutations in their LTR. Here we present a detailed analysis of the promoter activity of these genetic elements, which was comparable to those of virulent isolates. An AP-1 binding site was shown to be crucial for promoter activity in reporter gene assays and also in the context of a replicating molecular clone. Other sites, such as AML(vis) and a conserved E-box, appeared to be less crucial. Analysis of a unique AP-4 site showed a clear discrepancy between results obtained with reporter gene assays and those with mutated viruses. Within the limits of this in vitro study, we did not find evidence pointing to the LTR as the genetic correlate of attenuation for these viruses. Finally, the limited replication of SRLV A4 in mammary cell culture could not explain the suggested mammary tropism. In contrast, and in view of the abundance of macrophages in the mammary gland, it is the striking replication capacity of SRLV A4 in these cells, unaffected by all LTR mutations tested, which may explain the apparent mammary tropism of these viruses. PMID:27114068

  17. Abundance recovery error analysis using simulated AVIRIS data

    NASA Technical Reports Server (NTRS)

    Stoner, William W.; Harsanyi, Joseph C.; Farrand, William H.; Wong, Jennifer A.

    1992-01-01

    Measurement noise and imperfect atmospheric correction translate directly into errors in the determination of the surficial abundance of materials from imaging spectrometer data. The effects of errors on abundance recovery were investigated previously using Monte Carlo simulation methods by Sabol et. al. The drawback of the Monte Carlo approach is that thousands of trials are needed to develop good statistics on the probable error in abundance recovery. This computational burden invariably limits the number of scenarios of interest that can practically be investigated. A more efficient approach is based on covariance analysis. The covariance analysis approach expresses errors in abundance as a function of noise in the spectral measurements and provides a closed form result eliminating the need for multiple trials. Monte Carlo simulation and covariance analysis are used to predict confidence limits for abundance recovery for a scenario which is modeled as being derived from Airborne Visible/Infrared Imaging Spectrometer (AVIRIS).

  18. Detailed abundances of planet-hosting wide binaries. I. Did planet formation imprint chemical signatures in the atmospheres of HD 20782/81?

    SciTech Connect

    Mack III, Claude E.; Stassun, Keivan G.; Schuler, Simon C.; Norris, John

    2014-06-01

    Using high-resolution, high signal-to-noise echelle spectra obtained with Magellan/MIKE, we present a detailed chemical abundance analysis of both stars in the planet-hosting wide binary system HD 20782 + HD 20781. Both stars are G dwarfs, and presumably coeval, forming in the same molecular cloud. Therefore we expect that they should possess the same bulk metallicities. Furthermore, both stars also host giant planets on eccentric orbits with pericenters ≲0.2 AU. Here, we investigate if planets with such orbits could lead to the host stars ingesting material, which in turn may leave similar chemical imprints in their atmospheric abundances. We derived abundances of 15 elements spanning a range of condensation temperature, T {sub C} ≈ 40-1660 K. The two stars are found to have a mean element-to-element abundance difference of 0.04 ± 0.07 dex, which is consistent with both stars having identical bulk metallicities. In addition, for both stars, the refractory elements (T {sub C} >900 K) exhibit a positive correlation between abundance (relative to solar) and T {sub C}, with similar slopes of ≈1×10{sup –4} dex K{sup –1}. The measured positive correlations are not perfect; both stars exhibit a scatter of ≈5×10{sup –5} dex K{sup –1} about the mean trend, and certain elements (Na, Al, Sc) are similarly deviant in both stars. These findings are discussed in the context of models for giant planet migration that predict the accretion of H-depleted rocky material by the host star. We show that a simple simulation of a solar-type star accreting material with Earth-like composition predicts a positive—but imperfect—correlation between refractory elemental abundances and T {sub C}. Our measured slopes are consistent with what is predicted for the ingestion of 10-20 Earths by each star in the system. In addition, the specific element-by-element scatter might be used to distinguish between planetary accretion and Galactic chemical evolution scenarios.

  19. Detailed Abundances of Planet-hosting Wide Binaries. I. Did Planet Formation Imprint Chemical Signatures in the Atmospheres of HD 20782/81?

    NASA Astrophysics Data System (ADS)

    Mack, Claude E., III; Schuler, Simon C.; Stassun, Keivan G.; Norris, John

    2014-06-01

    Using high-resolution, high signal-to-noise echelle spectra obtained with Magellan/MIKE, we present a detailed chemical abundance analysis of both stars in the planet-hosting wide binary system HD 20782 + HD 20781. Both stars are G dwarfs, and presumably coeval, forming in the same molecular cloud. Therefore we expect that they should possess the same bulk metallicities. Furthermore, both stars also host giant planets on eccentric orbits with pericenters lsim0.2 AU. Here, we investigate if planets with such orbits could lead to the host stars ingesting material, which in turn may leave similar chemical imprints in their atmospheric abundances. We derived abundances of 15 elements spanning a range of condensation temperature, T C ≈ 40-1660 K. The two stars are found to have a mean element-to-element abundance difference of 0.04 ± 0.07 dex, which is consistent with both stars having identical bulk metallicities. In addition, for both stars, the refractory elements (T C >900 K) exhibit a positive correlation between abundance (relative to solar) and T C, with similar slopes of ≈1×10-4 dex K-1. The measured positive correlations are not perfect; both stars exhibit a scatter of ≈5×10-5 dex K-1 about the mean trend, and certain elements (Na, Al, Sc) are similarly deviant in both stars. These findings are discussed in the context of models for giant planet migration that predict the accretion of H-depleted rocky material by the host star. We show that a simple simulation of a solar-type star accreting material with Earth-like composition predicts a positive—but imperfect—correlation between refractory elemental abundances and T C. Our measured slopes are consistent with what is predicted for the ingestion of 10-20 Earths by each star in the system. In addition, the specific element-by-element scatter might be used to distinguish between planetary accretion and Galactic chemical evolution scenarios. The data presented herein were obtained at the Las Campanas

  20. Chemical abundance analysis of symbiotic giants - III. Metallicity and CNO abundance patterns in 24 southern systems

    NASA Astrophysics Data System (ADS)

    Gałan, Cezary; Mikołajewska, Joanna; Hinkle, Kenneth H.; Joyce, Richard R.

    2016-01-01

    The elemental abundances of symbiotic giants are essential to address the role of chemical composition in the evolution of symbiotic binaries, to map their parent population, and to trace their mass transfer history. However, the number of symbiotic giants with fairly well determined photospheric composition is still insufficient for statistical analyses. This is the third in a series of papers on the chemical composition of symbiotic giants determined from high-resolution (R ˜ 50 000), near-infrared spectra. Here we present results for 24 S-type systems. Spectrum synthesis methods employing standard local thermal equilibrium analysis and atmosphere models were used to obtain photospheric abundances of CNO and elements around the iron peak (Fe, Ti, Ni, and Sc). Our analysis reveals metallicities distributed in a wide range from slightly supersolar ([Fe/H] ˜ +0.35 dex) to significantly subsolar ([Fe/H] ˜ -0.8 dex) but principally with near-solar and slightly subsolar metallicity ([Fe/H] ˜ -0.4 to -0.3 dex). The enrichment in 14N isotope, found in all these objects, indicates that the giants have experienced the first dredge-up. This was confirmed in a number of objects by the low 12C/13C ratio (5-23). We found that the relative abundance of [Ti/Fe] is generally large in red symbiotic systems.

  1. Abundance of Hepatic Transporters in Caucasians: A Meta-Analysis.

    PubMed

    Burt, Howard J; Riedmaier, Arian Emami; Harwood, Matthew D; Crewe, H Kim; Gill, Katherine L; Neuhoff, Sibylle

    2016-10-01

    This study aimed to derive quantitative abundance values for key hepatic transporters suitable for in vitro-in vivo extrapolation within a physiologically based pharmacokinetic modeling framework. A meta-analysis was performed whereby data on abundance measurements, sample preparation methods, and donor demography were collated from the literature. To define values for a healthy Caucasian population, a subdatabase was created whereby exclusion criteria were applied to remove samples from non-Caucasian individuals, those with underlying disease, or those with subcellular fractions other than crude membrane. Where a clinically relevant active genotype was known, only samples from individuals with an extensive transporter phenotype were included. Authors were contacted directly when additional information was required. After removing duplicated samples, the weighted mean, geometric mean, standard deviation, coefficient of variation, and between-study homogeneity of transporter abundances were determined. From the complete database containing 24 transporters, suitable abundance data were available for 11 hepatic transporters from nine studies after exclusion criteria were applied. Organic anion transporting polypeptides OATP1B1 and OATP1B3 showed the highest population abundance in healthy adult Caucasians. For several transporters, the variability in abundance was reduced significantly once the exclusion criteria were applied. The highest variability was observed for OATP1B3 > OATP1B1 > multidrug resistance protein 2 > multidrug resistance gene 1. No relationship was found between transporter expression and donor age. To our knowledge, this study provides the first in-depth analysis of current quantitative abundance data for a wide range of hepatic transporters, with the aim of using these data for in vitro-in vivo extrapolation, and highlights the significance of investigating the background of tissue(s) used in quantitative transporter proteomic studies. Similar

  2. Analysis of Abundant sRNAs from Potato Leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study of sRNAs (sRNAs) is a rapidly evolving field seeking to understand their role in gene regulation, function and development. Combining next generation sequencing with the analysis of sRNAs allows the generation of large data sets to explore abundant sRNAs resulting from transcript degradat...

  3. Detailed analysis of methane hydrate concentrated zone of lobe type

    NASA Astrophysics Data System (ADS)

    Kobayashi, T.; Saeki, T.; Inamori, T.; Fujii, T.; Shimoda, N.

    2007-12-01

    Japan Oil, Gas and Metals National Corporation (hereinafter called JOGMEC), as a member of MH21 Research Consortium, takes charge of a study of the Research for Resources Assessment, and is pursuing a possibility that methane hydrate, which is presumed to be distributed around ocean area of Japan, will be energy resources. JOGMEC is currently conducting analysis of seismic data which was acquired by 3D seismic survey conducted from Tokai-Oki to Kumano-nada in the eastern Nankai Trough by METI (Ministry of Economy, Trade and Industry) in 2002 under the national program of assessment for methane hydrates as energy resources. It was understood that methane hydrate was correlated to high resistivity and high velocity based on the results of drilling surveys and velocity analysis, and that methane hydrate concentrated zones can be roughly classified into the channels and lobes in seismic geomorphology because they were characterized with reserves consisting turbidite sand bodies. In this study, the detailed analysis of the inner structure of the methane hydrate concentrated zone of lobe type was conducted to understand the occurrence configurations of methane hydrates. The reflected waves that construct the methane hydrate concentrated zones in the seismic data were extracted and those reflected waves were classified into some groups every one reflector. As the result, some reflectors that construct the methane hydrate concentrated zones were revealed. Those reflectors show the layers including methane hydrates, and the detailed distribution of the methane hydrates in those layers was revealed by the intensity distribution of the amplitude. This time, we introduce the example of the detailed analysis of the methane hydrate concentrated zone in the lobe of submarine fan.

  4. A detailed analysis of Mariner nine TV navigation data.

    NASA Technical Reports Server (NTRS)

    Breckenridge, W. G.; Acton, C. H., Jr.

    1972-01-01

    Mariner 9 data analysis showed a good performance of the Mars probe planetary approach navigation systems and a good agreement between measured and predicted probe-approach characteristics. It was found that all operations were completed on time and that the calibration of the instruments and the observation of a greater-than-planned number of stars resulted in a higher-than-expected measurement accuracy. The key instruments of the Mariner were TV cameras taking pictures of Phobos and Deimos against a background of stars, calibrated sun and star sensors, and a scan platform. The error models used for optical navigation system elements, the calibration of the scan platform and of the TV cameras, and the image detection and location techniques are discussed in detail.

  5. A Detailed Spectroscopic Analysis of The EQ Pegasi System

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua E.; Murphy, Simon; Riedel, Adric R.

    2015-01-01

    EQ Pegasi (GJ 896, HIP 116132 ) is a resolved binary system comprised of mid-M dwarfs at a distance of only 6.2 pc. The system has been studied extensively over a broad range of wavelengths from the X-ray to the radio. These observations reveal both components are variable, flare, and exhibit high levels of magnetic activity. The pair were recently proposed as members of a nearby young kinematic association on the basis of consistent Galactic kinematics, strong X-ray emission, and color-magnitude diagram position. Thus, they may be the closest pre-main-sequence system to the Sun. Here we present a detailed analysis of EQ Peg A and B using medium resolution spectra covering ~0.5-2.5 microns. We investigate spectral types, chromospheric activity indicators, lithium depletion, and gravity sensitive alkali lines and molecular bands to characterize the system and place constraints on its age.

  6. Detailed Modeling and Analysis of the CPFM Dataset

    NASA Technical Reports Server (NTRS)

    Swartz, William H.; Lloyd, Steven A.; DeMajistre, Robert

    2004-01-01

    A quantitative understanding of photolysis rate coefficients (or "j-values") is essential to determining the photochemical reaction rates that define ozone loss and other crucial processes in the atmosphere. j-Values can be calculated with radiative transfer models, derived from actinic flux observations, or inferred from trace gas measurements. The principal objective of this study is to cross-validate j-values from the Composition and Photodissociative Flux Measurement (CPFM) instrument during the Photochemistry of Ozone Loss in the Arctic Region In Summer (POLARIS) and SAGE I11 Ozone Loss and Validation Experiment (SOLVE) field campaigns with model calculations and other measurements and to use this detailed analysis to improve our ability to determine j-values. Another objective is to analyze the spectral flux from the CPFM (not just the j-values) and, using a multi-wavelength/multi-species spectral fitting technique, determine atmospheric composition.

  7. Detailed Uncertainty Analysis of the ZEM-3 Measurement System

    NASA Technical Reports Server (NTRS)

    Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

    2014-01-01

    The measurement of Seebeck coefficient and electrical resistivity are critical to the investigation of all thermoelectric systems. Therefore, it stands that the measurement uncertainty must be well understood to report ZT values which are accurate and trustworthy. A detailed uncertainty analysis of the ZEM-3 measurement system has been performed. The uncertainty analysis calculates error in the electrical resistivity measurement as a result of sample geometry tolerance, probe geometry tolerance, statistical error, and multi-meter uncertainty. The uncertainty on Seebeck coefficient includes probe wire correction factors, statistical error, multi-meter uncertainty, and most importantly the cold-finger effect. The cold-finger effect plagues all potentiometric (four-probe) Seebeck measurement systems, as heat parasitically transfers through thermocouple probes. The effect leads to an asymmetric over-estimation of the Seebeck coefficient. A thermal finite element analysis allows for quantification of the phenomenon, and provides an estimate on the uncertainty of the Seebeck coefficient. The thermoelectric power factor has been found to have an uncertainty of +9-14 at high temperature and 9 near room temperature.

  8. Detailed abundances for a large sample of giant stars in the globular cluster 47 Tucanae (NGC 104)

    SciTech Connect

    Cordero, M. J.; Pilachowski, C. A.; Johnson, C. I.; McDonald, I.; Zijlstra, A. A.; Simmerer, J. E-mail: catyp@astro.indiana.edu E-mail: mcdonald@jb.man.ac.uk E-mail: jennifer@physics.utah.edu

    2014-01-01

    47 Tuc is an ideal target to study chemical evolution and globular cluster (GC) formation in massive more metal-rich GCs, as it is the closest massive GC. We present chemical abundances for O, Na, Al, Si, Ca, Ti, Fe, Ni, La, and Eu in 164 red giant branch stars in the massive GC 47 Tuc using spectra obtained with both the Hydra multifiber spectrograph at the Blanco 4 m telescope and the FLAMES multiobject spectrograph at the Very Large Telescope. We find an average [Fe/H] = –0.79 ± 0.09 dex, consistent with literature values, as well as overabundances of alpha-elements ([α/Fe] ∼ 0.3 dex). The n-capture process elements indicate that 47 Tuc is r process-dominated ([Eu/La] = +0.24), and the light elements O, Na, and Al exhibit star-to-star variations. The Na-O anticorrelation, a signature typically seen in Galactic GCs, is present in 47 Tuc, and extends to include a small number of stars with [O/Fe] ∼ –0.5. Additionally, the [O/Na] ratios of our sample reveal that the cluster stars can be separated into three distinct populations. A Kolmogorov-Smirnov test demonstrates that the O-poor/Na-rich stars are more centrally concentrated than the O-rich/Na-poor stars. The observed number and radial distribution of 47 Tuc's stellar populations, as distinguished by their light element composition, agrees closely with the results obtained from photometric data. We do not find evidence supporting a strong Na-Al correlation in 47 Tuc, which is consistent with current models of asymptotic giant branch nucleosynthesis yields.

  9. Abundance analysis of roAp stars. II. HD 203932

    NASA Astrophysics Data System (ADS)

    Gelbmann, M.; Kupka, F.; Weiss, W. W.; Mathys, G.

    1997-03-01

    A new tool to simplify abundance analyses which is based on stand-alone programs has been applied to the rapidly oscillating Ap star HD 203932 (BI Mic, CD -30 18600, SAO 212996; Ap(SrEu), V=8.82mag). The spectroscopically determined T_eff_=7450+/-100K and logg=4.3+/-0.15 put this star close to the ZAMS. Other fundamental atmospheric parameters are v_micro_<0.6km/s and the total abundance of all iron peak elements [M/H]=0.0+/-0.1. The fundamental parameters put HD 203932 in a region of the HR-diagram where convection starts becoming efficient and the standard mixing length theory models lead to severe problems in the determination of the atmospheric parameters. The difference between the upper limit for logg obtained from several variants of the mixing length theory and the Canuto-Mazzitelli model indicates that the choice of a particular convection model can influence the determination of basic stellar parameters. For the first time abundances were determined for HD 203932 showing a pattern for the 35 investigated elements which is similar to α Cir (Kupka et al. 1996A&A...308..886K, Paper I). Fe and Ni have about solar abundance, Cr and especially Co are clearly overabundant as well as rare earth elements. The most underabundant element is Sc, followed by C, N, and O, which is a common property of CP2 stars. The lack of a correlation in our data between individual line abundances and their effective Lande factors implies a mean magnetic field modulus not exceeding few kG. Compared to the last homogeneous spectroscopic investigation of a large sample of chemically peculiar stars (21 cool Ap stars, Adelman 1973ApJ...183...95A), our analysis is based on data with higher spectral resolution and signal-to-noise ratio. Even more important, we are using a much larger atomic line data base with more precise atomic parameters than available more than twenty years ago.

  10. Impregnating unconsolidated pyroclastic sequences: A tool for detailed facies analysis

    NASA Astrophysics Data System (ADS)

    Klapper, Daniel; Kueppers, Ulrich; Castro, Jon M.; Pacheco, Jose M. R.; Dingwell, Donald B.

    2010-05-01

    The interpretation of volcanic eruptions is usually derived from direct observation and the thorough analysis of the deposits. Processes in vent-proximal areas are usually not directly accessible or likely to be obscured. Hence, our understanding of proximal deposits is often limited as they were produced by the simultaneous events stemming from primary eruptive, transportative, and meteorological conditions. Here we present a method that permits for a direct and detailed quasi in-situ investigation of loose pyroclastic units that are usually analysed in the laboratory for their 1) grain-size distribution, 2) componentry, and 3) grain morphology. As the clast assembly is altered during sampling, the genesis of a stratigraphic unit and the relative importance of the above mentioned deposit characteristics is hard to achieve. In an attempt to overcome the possible loss of information during conventional sampling techniques, we impregnated the cleaned surfaces of proximal, unconsolidated units of the 1957-58 Capelinhos eruption on Faial, Azores. During this basaltic, emergent eruption, fluxes in magma rise rate led to a repeated build-up and collapse of tuff cones and consequently to a shift between phreatomagmatic and magmatic eruptive style. The deposits are a succession of generally parallel bedded, cm- to dm-thick layers with a predominantly ashy matrix. The lapilli content is varying gradually; the content of bombs is enriched in discrete layers without clear bomb sags. The sample areas have been cleaned and impregnated with two-component glue (EPOTEK 301). For approx. 10 * 10 cm, a volume of mixed glue of 20 ml was required. Using a syringe, this low-viscosity, transparent glue could be easily applied on the target area. We found that the glue permeated the deposit as deep as 5 mm. After > 24 h, the glue was sufficiently dry to enable the sample to be laid open. This impregnation method renders it possible to cut and polish the sample and investigate grain

  11. Impregnating unconsolidated pyroclastic sequences: A tool for detailed facies analysis

    NASA Astrophysics Data System (ADS)

    Klapper, D.; Kueppers, U.; Castro, J. M.

    2009-12-01

    The interpretation of volcanic eruptions is usually derived from direct observation and the thorough analysis of the deposits. Processes in vent-proximal areas are usually not directly accessible or likely to be obscured. Hence, our understanding of proximal deposits is often limited as they were produced by the simultaneous events stemming from primary eruptive, transportative, and meteorological conditions. Here we present a method that permits for a direct and detailed quasi in-situ investigation of loose pyroclastic units that are usually analysed in the laboratory for their 1) grain-size distribution, 2) componentry, and 3) grain morphology. As the clast assembly is altered during sampling, the genesis of a stratigraphic unit and the relative importance of the above mentioned deposit characteristics is hard to achieve. In an attempt to overcome the possible loss of information during conventional sampling techniques, we impregnated the cleaned surfaces of proximal, unconsolidated units of the 1957-58 Capelinhos eruption on Faial, Azores. During this basaltic, emergent eruption, fluxes in magma rise rate led to a repeated build-up and collapse of tuff cones and consequently to a shift between phreatomagmatic and magmatic eruptive style. The deposits are a succession of generally parallel bedded, cm- to dm-thick layers with a predominantly ashy matrix. The lapilli content is varying gradually; the content of bombs is enriched in discrete layers without clear bomb sags. The sample areas have been cleaned and impregnated with a two-component glue (EPOTEK 301). For approx. 10 * 10 cm, a volume of mixed glue of 20 ml was required. This low-viscosity, transparent glue allowed for an easy application on the target area by means of a syringe and permeated the deposit as deep as 5 mm. After > 24 h, the glue was sufficiently dry to enable the sample to be laid open. This impregnation method renders it possible to cut and polish the sample and investigate grain

  12. Exploring the Milky Way stellar disk. A detailed elemental abundance study of 714 F and G dwarf stars in the solar neighbourhood

    NASA Astrophysics Data System (ADS)

    Bensby, T.; Feltzing, S.; Oey, M. S.

    2014-02-01

    Aims: The aim of this paper is to explore and map the age and abundance structure of the stars in the nearby Galactic disk. Methods: We have conducted a high-resolution spectroscopic study of 714 F and G dwarf and subgiant stars in the Solar neighbourhood. The star sample has been kinematically selected to trace the Galactic thin and thick disks to their extremes, the metal-rich stellar halo, sub-structures in velocity space such as the Hercules stream and the Arcturus moving group, as well as stars that cannot (kinematically) be associated with either the thin disk or the thick disk. The determination of stellar parameters and elemental abundances is based on a standard analysis using equivalent widths and one-dimensional, plane-parallel model atmospheres calculated under the assumption of local thermodynamical equilibrium (LTE). The spectra have high resolution (R = 40 000-110 000) and high signal-to-noise (S/N = 150-300) and were obtained with the FEROS spectrograph on the ESO 1.5 m and 2.2 m telescopes, the SOFIN and FIES spectrographs on the Nordic Optical Telescope, the UVES spectrograph on the ESO Very Large Telescope, the HARPS spectrograph on the ESO 3.6 m telescope, and the MIKE spectrograph on the Magellan Clay telescope. The abundances from individual Fe i lines were were corrected for non-LTE effects in every step of the analysis. Results: We present stellar parameters, stellar ages, kinematical parameters, orbital parameters, and detailed elemental abundances for O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, Y, and Ba for 714 nearby F and G dwarf stars. Our data show that there is an old and α-enhanced disk population, and a younger and less α-enhanced disk population. While they overlap greatly in metallicity between -0.7 < [Fe/H] ≲ +0.1, they show a bimodal distribution in [α/Fe]. This bimodality becomes even clearer if stars where stellar parameters and abundances show larger uncertainties (Teff ≲ 5400 K) are discarded, showing that it is

  13. Measuring Detailed Chemical Abundances from Co-added Medium-resolution Spectra. I. Tests Using Milky Way Dwarf Spheroidal Galaxies and Globular Clusters

    NASA Astrophysics Data System (ADS)

    Yang, Lei; Kirby, Evan N.; Guhathakurta, Puragra; Peng, Eric W.; Cheng, Lucy

    2013-05-01

    The ability to measure metallicities and α-element abundances in individual red giant branch (RGB) stars using medium-resolution spectra (R ≈ 6000) is a valuable tool for deciphering the nature of Milky Way dwarf satellites and the history of the Galactic halo. Extending such studies to more distant systems like Andromeda is beyond the ability of the current generation of telescopes, but by co-adding the spectra of similar stars, we can attain the necessary signal-to-noise ratio (S/N) to make detailed abundance measurements. In this paper, we present a method to determine metallicities and α-element abundances using the co-addition of medium-resolution spectra. We test the method of spectral co-addition using high-S/N spectra of more than 1300 RGB stars from Milky Way globular clusters and dwarf spheroidal galaxies obtained with the Keck II telescope/DEIMOS spectrograph. We group similar stars using photometric criteria and compare the weighted ensemble average abundances ([Fe/H], [Mg/Fe], [Si/Fe], [Ca/Fe], and [Ti/Fe]) of individual stars in each group with the measurements made on the corresponding co-added spectrum. We find a high level of agreement between the two methods, which permits us to apply this co-added spectra technique to more distant RGB stars, like stars in the M31 satellite galaxies. This paper outlines our spectral co-addition and abundance measurement methodology and describes the potential biases in making these measurements. Data herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  14. MEASURING DETAILED CHEMICAL ABUNDANCES FROM CO-ADDED MEDIUM-RESOLUTION SPECTRA. I. TESTS USING MILKY WAY DWARF SPHEROIDAL GALAXIES AND GLOBULAR CLUSTERS

    SciTech Connect

    Yang Lei; Peng, Eric W.; Kirby, Evan N.; Guhathakurta, Puragra

    2013-05-01

    The ability to measure metallicities and {alpha}-element abundances in individual red giant branch (RGB) stars using medium-resolution spectra (R Almost-Equal-To 6000) is a valuable tool for deciphering the nature of Milky Way dwarf satellites and the history of the Galactic halo. Extending such studies to more distant systems like Andromeda is beyond the ability of the current generation of telescopes, but by co-adding the spectra of similar stars, we can attain the necessary signal-to-noise ratio (S/N) to make detailed abundance measurements. In this paper, we present a method to determine metallicities and {alpha}-element abundances using the co-addition of medium-resolution spectra. We test the method of spectral co-addition using high-S/N spectra of more than 1300 RGB stars from Milky Way globular clusters and dwarf spheroidal galaxies obtained with the Keck II telescope/DEIMOS spectrograph. We group similar stars using photometric criteria and compare the weighted ensemble average abundances ([Fe/H], [Mg/Fe], [Si/Fe], [Ca/Fe], and [Ti/Fe]) of individual stars in each group with the measurements made on the corresponding co-added spectrum. We find a high level of agreement between the two methods, which permits us to apply this co-added spectra technique to more distant RGB stars, like stars in the M31 satellite galaxies. This paper outlines our spectral co-addition and abundance measurement methodology and describes the potential biases in making these measurements.

  15. Damped Mechanical Oscillator: Experiment and Detailed Energy Analysis

    NASA Astrophysics Data System (ADS)

    Corridoni, Tommaso; D'Anna, Michele; Fuchs, Hans

    2014-02-01

    The damped oscillator is discussed in every high school textbook or introductory physics course, and a large number of papers are devoted to it in physics didactics journals. Papers typically focus on kinematic and dynamic aspects and less often on energy. Among the latter, some are devoted to the peculiar decreasing behavior of energy characterized by ripples, which can easily be demonstrated by using a dynamic modeling approach.8 In this note we consider an oscillator consisting of a cart running on a horizontal track, two springs, and a damping device created with magnets and a metal plate attached to the cart (Fig. 1). Using sensors and data-acquisition software,9 we measure kinematic quantities and three forces: those of the springs on the cart and, separately, the force between magnets and the plate. A detailed analysis of the energy exchanges between the cart and the interacting parts is obtained. In particular, we show that only the energy exchanges with the magnets are affected by dissipative processes while over a suitable time interval the net energy exchanged between cart and springs equals zero.

  16. Patterns of Communication through Interpreters: A Detailed Sociolinguistic Analysis

    PubMed Central

    Aranguri, Cesar; Davidson, Brad; Ramirez, Robert

    2006-01-01

    BACKGROUND Numerous articles have detailed how the presence of an interpreter leads to less satisfactory communication with physicians; few have studied how actual communication takes place through an interpreter in a clinical setting. OBJECTIVE Record and analyze physician-interpreter-patient interactions. DESIGN Primary care physicians with high-volume Hispanic practices were recruited for a communication study. Dyslipidemic Hispanic patients, either monolingual Spanish or bilingual Spanish-English, were recruited on the day of a normally scheduled appointment and, once consented, recorded without a researcher present in the room. Separate postvisit interviews were conducted with the patient and the physician. All interactions were fully transcribed and analyzed. PARTICIPANTS Sixteen patients were recorded interacting with 9 physicians. Thirteen patients used an interpreter with 8 physicians, and 3 patients spoke Spanish with the 1 bilingual physician. APPROACH Transcript analysis based on sociolinguistic and discourse analytic techniques, including but not limited to time speaking, analysis of questions asked and answered, and the loss of semantic information. RESULTS Speech was significantly reduced and revised by the interpreter, resulting in an alteration of linguistic features such as content, meaning, reinforcement/validation, repetition, and affect. In addition, visits that included an interpreter had virtually no rapport-building “small talk,” which typically enables the physician to gain comprehensive patient history, learn clinically relevant information, and increase emotional engagement in treatment. CONCLUSIONS The presence of an interpreter increases the difficulty of achieving good physician-patient communication. Physicians and interpreters should be trained in the process of communication and interpretation, to minimize conversational loss and maximize the information and relational exchange with interpreted patients. PMID:16808747

  17. Chemical abundance analysis of symbiotic giants - I. RW Hya and SY Mus

    NASA Astrophysics Data System (ADS)

    Mikołajewska, Joanna; Gałan, Cezary; Hinkle, Kenneth H.; Gromadzki, Mariusz; Schmidt, Mirosław R.

    2014-06-01

    The study of symbiotic systems is of considerable importance in our understanding of binary system stellar evolution in systems where mass-loss or transfer takes place. Elemental abundances are of special significance since they can be used to track mass exchange. However, there are few symbiotic giants for which the abundances are fairly well determined. Here, we present for the first time a detailed analysis of the chemical composition for the giants in the RW Hya and SY Mus systems. The analysis is based on high-resolution (R ˜ 50 000), high signal-to-noise (S/N), near-IR spectra. Spectrum synthesis employing standard local thermal equilibrium (LTE) analysis and atmosphere models was used to obtain photospheric abundances of CNO and elements around the iron peak (Sc, Ti, Fe, and Ni). Our analysis reveals a significantly sub-solar metallicity, [Fe/H] ˜ -0.75, for the RW Hya giant confirming its membership in the Galactic halo population and a near-solar metallicity for the SY Mus giant. The very low 12C/13C isotopic ratios, ˜6-10, derived for both objects indicate that the giants have experienced the first dredge-up.

  18. Human Factors Considerations in New Nuclear Power Plants: Detailed Analysis.

    SciTech Connect

    OHara,J.; Higgins, J.; Brown, W.; Fink, R.

    2008-02-14

    This Nuclear Regulatory Commission (NRC) sponsored study has identified human-performance issues in new and advanced nuclear power plants. To identify the issues, current industry developments and trends were evaluated in the areas of reactor technology, instrumentation and control technology, human-system integration technology, and human factors engineering (HFE) methods and tools. The issues were organized into seven high-level HFE topic areas: Role of Personnel and Automation, Staffing and Training, Normal Operations Management, Disturbance and Emergency Management, Maintenance and Change Management, Plant Design and Construction, and HFE Methods and Tools. The issues where then prioritized into four categories using a 'Phenomena Identification and Ranking Table' methodology based on evaluations provided by 14 independent subject matter experts. The subject matter experts were knowledgeable in a variety of disciplines. Vendors, utilities, research organizations and regulators all participated. Twenty issues were categorized into the top priority category. This Brookhaven National Laboratory (BNL) technical report provides the detailed methodology, issue analysis, and results. A summary of the results of this study can be found in NUREG/CR-6947. The research performed for this project has identified a large number of human-performance issues for new control stations and new nuclear power plant designs. The information gathered in this project can serve as input to the development of a long-term strategy and plan for addressing human performance in these areas through regulatory research. Addressing human-performance issues will provide the technical basis from which regulatory review guidance can be developed to meet these challenges. The availability of this review guidance will help set clear expectations for how the NRC staff will evaluate new designs, reduce regulatory uncertainty, and provide a well-defined path to new nuclear power plant licensing.

  19. A detailed petrological analysis of hydrated, low-nickel, nonchondritic stratospheric dust particles

    NASA Technical Reports Server (NTRS)

    Rietmeijer, Frans J. M.

    1992-01-01

    A detailed petrological analysis of three low-Ni, K-bearing, nonchondritic stratospheric dust particles is performed, and these particles are compared to products of high-energy, explosive (Plinian-type) volcanic events. The analytical electron microscope (AEM) analyses show pervasive layer silicates, carbonate and goethite, and chemical fractionation in the matrix of these particles similar to hydrothermal alteration in volcanic ejecta. Along with low Ni content and the presence of potassium, the texture and mineralogy of particles L2001-18, L2001-20, and L2002 C2 are similar to at least two nonchondritic stratospheric dust particles of the igneous subgroup for which an extraterrestrial origin has been suggested based on their minor- and trace-element abundances. The petrological characteristics of some low-Ni, K-bearing nonchondritic stratospheric dust particles supports a probable terrestrial volcanic origin, but the AEM data alone cannot exclude an extraterrestrial origin for these particles.

  20. Lattice QCD at the physical point: simulation and analysis details

    NASA Astrophysics Data System (ADS)

    Dürr, S.; Fodor, Z.; Hoelbling, C.; Katz, S. D.; Krieg, S.; Kurth, T.; Lellouch, L.; Lippert, T.; Szabó, K. K.; Vulvert, G.

    2011-08-01

    We give details of our precise determination of the light quark masses m ud = ( m u + m d )/2 and m s in 2 + 1 flavor QCD, with simulated pion masses down to 120 MeV, at five lattice spacings, and in large volumes. The details concern the action and algorithm employed, the HMC force with HEX smeared clover fermions, the choice of the scale setting procedure and of the input masses. After an overview of the simulation parameters, extensive checks of algorithmic stability, autocorrelation and (practical) ergodicity are reported. To corroborate the good scaling properties of our action, explicit tests of the scaling of hadron masses in N f = 3 QCD are carried out. Details of how we control finite volume effects through dedicated finite volume scaling runs are reported. To check consistency with SU(2) Chiral Perturbation Theory the behavior of M π 2 /m ud and F π as a function of m ud is investigated. Details of how we use the RI/MOM procedure with a separate continuum limit of the running of the scalar density R S ( μ, μ') are given. This procedure is shown to reproduce the known value of r 0 m s in quenched QCD. Input from dispersion theory is used to split our value of m ud into separate values of m u and m d . Finally, our procedure to quantify both systematic and statistical uncertainties is discussed.

  1. Task analysis: a detailed example of stepping up from JSA

    SciTech Connect

    Banks, W.W.; Paramore, B.A.; Buys, J.R.

    1984-10-01

    This paper discusses a pilot task analysis of operations in a proposed facility for the cutting and packaging of radioactively contaminated gloveboxes, for long-term storage or burial. The objective was to demonstrate how task analysis may be used as a tool for planning and risk management. Two specific products were generated - preliminary operating procedures and training requirements. The task data base, procedures list and training requirements developed were intended as first order categorizations. The analysis was limited to tasks that will be performed within the boundaries of the operational facility and the associated load-out area. The analysis documents tasks to be performed by D and D (Decontamination and Decommissioning) Workers. However, the analysis included all tasks identified as an integral part of glovebox processing within the facility. Thus tasks involving Radiation Protection Technicians (RPTs) are included. Based on hazard assessments, it is planned that at least two RPTs will be assigned full-time to the facility, so they may be considered part of its crew. Similarly, supervisory/administrative tasks are included where they were determined to be directly part of process sequences, such as obtaining appropriate certification. 11 tables.

  2. An analysis of commitment strategies in planning: The details

    NASA Technical Reports Server (NTRS)

    Minton, Steven; Bresina, John; Drummond, Mark; Philips, Andrew B.

    1991-01-01

    We compare the utility of different commitment strategies in planning. Under a 'least commitment strategy', plans are represented as partial orders and operators are ordered only when interactions are detected. We investigate claims of the inherent advantages of planning with partial orders, as compared to planning with total orders. By focusing our analysis on the issue of operator ordering commitment, we are able to carry out a rigorous comparative analysis of two planners. We show that partial-order planning can be more efficient than total-order planning, but we also show that this is not necessarily so.

  3. Lightning climatology in the Congo Basin: detailed analysis

    NASA Astrophysics Data System (ADS)

    Soula, Serge; Kigotsi, Jean; Georgis, Jean-François; Barthe, Christelle

    2016-04-01

    The lightning climatology of the Congo Basin including several countries of Central Africa is analyzed in detail for the first time. It is based on World Wide Lightning Location Network (WWLLN) data for the period from 2005 to 2013. A comparison of these data with the Lightning Imaging Sensor (LIS) data for the same period shows the WWLLN detection efficiency (DE) in the region increases from about 1.70 % in the beginning of the period to 5.90 % in 2013, relative to LIS data, but not uniformly over the whole 2750 km × 2750 km area. Both the annual flash density and the number of stormy days show sharp maximum values localized in eastern of Democratic Republic of Congo (DRC) and west of Kivu Lake, regardless of the reference year and the period of the year. These maxima reach 12.86 fl km-2 and 189 days, respectively, in 2013, and correspond with a very active region located at the rear of the Virunga mountain range characterised with summits that can reach 3000 m. The presence of this range plays a role in the thunderstorm development along the year. The estimation of this local maximum of the lightning density by taking into account the DE, leads to a value consistent with that of the global climatology by Christian et al. (2003) and other authors. Thus, a mean maximum value of about 157 fl km-2 y-1 is found for the annual lightning density. The zonal distribution of the lightning flashes exhibits a maximum between 1°S and 2°S and about 56 % of the flashes located below the equator in the 10°S - 10°N interval. The diurnal evolution of the flash rate has a maximum between 1400 and 1700 UTC, according to the reference year, in agreement with previous works in other regions of the world.

  4. Hydrogen-fueled scramjets: Potential for detailed combustor analysis

    NASA Technical Reports Server (NTRS)

    Beach, H. L., Jr.

    1976-01-01

    Combustion research related to hypersonic scramjet (supersonic combustion ramjet) propulsion is discussed from the analytical point of view. Because the fuel is gaseous hydrogen, mixing is single phase and the chemical kinetics are well known; therefore, the potential for analysis is good relative to hydro-carbon fueled engines. Recent progress in applying two and three dimensional analytical techniques to mixing and reacting flows indicates cause for optimism, and identifies several areas for continuing effort.

  5. A Detailed Analysis of Stellar Populations in Galaxies During Reionization

    NASA Astrophysics Data System (ADS)

    Finkelstein, Steven

    2010-09-01

    We request archival funds to complete a robust study of galaxies in the z > 7 Universe using a new set of unprecedentedly deep data from HST WFC3/IR. These data probe an epoch when the Universe was only 500 - 800 Myr old, placing constraints on the earliest phases of galaxy formation. We recently completed a thorough study of the HUDF with WFC3. Using robust analysis techniques to study the stellar populations in these galaxies, we improved upon early release papers to provide a valuable analysis to the community. We will continue this work, combining the HUDF, HUDF-01 and HUDF-02 datasets to compile a sample ~ 3X larger. We will search for galaxies at z = 7 - 9 within this dataset by computing photometric redshifts, which offers a smaller redshift uncertainty than typical Lyman break color-criteria selection, as well as allowing a more complete census of the galaxy population at z > 7. We will run bootstrap Monte Carlo simulations on our sample, which place strong constraints on the presence of primordial stellar populations in these galaxies - this is more physically accurate than other studies, which have only reported the standard error on the mean, which does not give information on how well one can rule out certain scenarios. Lastly, we will fit the full spectral energy distributions of these objects to a suite of stellar population models, computing confidence ranges on each property. As we found in our previous work, although the age and dust are difficult to constrain, the stellar mass is well constrained with only rest-UV detections due to the old age of the Universe. A 3X increase in sample size nearly doubles the accuracy with which we can pin down the stellar populations in these galaxies.At such high redshifts, large samples of galaxies are expensive and extremely hard to come by. The opportunity to examine a sample of ~ 100 z > 7 galaxies is a unique one, and by applying our robust techniques, we will present the most complete analysis of the galaxy

  6. Detailed analysis of POD method applied on turbulent flow

    NASA Astrophysics Data System (ADS)

    Kellnerova, Radka; Kukacka, Libor; Uruba, Vaclav; Jurcakova, Klara; Janour, Zbynek

    2012-04-01

    Proper orthogonal decomposition (POD) of a very turbulent flow inside a street canyon is performed. The energy contribution of each mode is obtained. Also, physical meaning of the POD result is clarified. Particular modes of POD are assigned to the particular flow events like a sweep event, a vortex behind a roof or a vortex at the bottom of a street. Test of POD sensitivity to the acquisition time of data records is done. Test with decreasing sample frequency is also executed. Further, interpolation of POD expansion coefficient is performed in order to test possible increase in sample frequency and get new information about the flow from the POD analysis. We tested a linear and a spline type of the interpolation and the linear one carried out a slightly better result.

  7. The Kirki episode: Detailed biomarker analysis provides some surprises

    SciTech Connect

    Currie, T.J.; Alexander, R.; Kagi, R.I.

    1996-12-31

    On Sunday 21st July 1991 the oil tanker Kirki caught fire when its bow broke off in heavy seas just 40 km off the Western Australian coastline near Jurien, approximately 200 km north of Perth. The tanker was carrying 80,000 tonnes of Murban light crude oil from the Middle East. Over the next three days approximately 10,000 tonnes of this oil was released into the marine environment, the heavy seas rapidly spreading the oil slick to a thin sheen. There was extensive media coverage of this event and it was widely considered that the spill posed a serious environmental threat to reef systems, recreational beaches and the local rock lobster fishery. This report describes results of analysis performed on several of the samples.

  8. A Detailed Phylogenetic Analysis of FIV in the United States

    PubMed Central

    Weaver, Eric A.

    2010-01-01

    Background Feline immunodeficiency virus (FIV) is a lentivirus associated with AIDS-like illnesses in cats and has been used as a model for the study of human immunodeficiency virus (HIV). A feature of HIV and FIV infection is the continually increasing divergence among viral isolates between different individuals, as well as within the same individuals. Methodology/Principal Findings The goal of this study was to determine the phylogenetic patterns of viral isolates obtained within the United States (U.S.) by focusing on the variable, V3-V4, region of the FIV envelope gene. Conclusions/Significance Data indicate that FIV, from within the U.S., localize to four viral clades, A, B, C, and F. Also shown is the geographic isolation of strains where clade A and clade B are found predominately on the west coast; however, clade B is also found throughout the U.S. and represents the predominant clade. This study presents a complete and conclusive analysis of FIV isolates from within the U.S. and may be used as the essential basis for the development of an effective multi-clade vaccine. PMID:20711253

  9. Detailed analysis of the structural consequences of railgun augumentation

    SciTech Connect

    Wellman, G.W.; Schuler, K.W.

    1988-06-01

    The advantage of augmenting a plasma railgun is to provide the same driving force on the projectile as in an unaugmented railgun at a lower plasma arc current, thus producing less erosion and barrel damage. However, there are structural consequences to railgun augmentation which must be overcome before the advantages of lower plasma arc currents can be realized. To investigate these consequences, a bolted V-block supporting structure is considered with two cores; unaugmented (a single pair of conducting rails), and augmented (conducting rails augmented by a second tandem set of conductors). For each core, a two-dimensional dynamic finite element structural analysis is performed. The loadings, applied sequentially, consist of the static bolt preload, the plasma pressure behind the projectile, and the magnetic pressure induced by currents flowing in the rails or augmenting conductors. The magnetic pressure induced by currents flowing in the rails or augmenting conductors. A maximum rail current is found for which the unaugmented railgun can be fired without permanent deformation of the gun bore, thus allowing repeated firings. For the augmented railgun, at the same projectile acceleration, large permanent deformations are shown. 7 refs., 41 figs., 2 tabs.

  10. Project VeSElkA: results of abundance analysis I - HD 71030, HD 95608, HD 116235 and HD 186568

    NASA Astrophysics Data System (ADS)

    LeBlanc, F.; Khalack, V.; Yameogo, B.; Thibeault, C.; Gallant, I.

    2015-11-01

    A portion of main-sequence stars, called chemically peculiar (CP) stars, show important abundance anomalies mainly due to atomic diffusion of the species within these stars. Certain CP stars have hydrodynamically stable atmospheres where atomic diffusion may dominate and lead to vertical abundance stratification there. Recently, Project VeSElkA (a word meaning rainbow in Ukrainian and standing for `Vertical Stratification of Element Abundances') was initiated with the goal to detect vertical stratification of chemical abundances in selected CP stars using high-resolution spectra with large signal-to-noise ratios. The first extensive and detailed series of results from atomic-line analysis is presented here for four stars of Project VeSElkA: HD 71030, HD 95608, HD 116235 and HD 186568. These stars were recently observed with ESPaDOnS at Canada-France-Hawaii Telescope. Strong evidence of iron stratification in the atmospheres of HD 95608 and HD 116235 was found. Chromium also shows a steep abundance gradient in the upper atmospheres of these two stars. No evidence of stratification is found for HD 71030 and HD 186568.

  11. Chemical abundance analysis of symbiotic giants. RW Hya, SY Mus, BX Mon, and AE Ara

    NASA Astrophysics Data System (ADS)

    Galan, C.; Mikolajewska, J.; Hinkle, K. H.; Schmidt, M. R.; Gromadzki, M.

    2014-04-01

    Symbiotic stars are the long period, binary systems of strongly interacting stars at the final stages of evolution which can be useful tool to understand the chemical evolution of the Galaxy and the formation of stellar populations. Knowledge of the chemical composition of the symbiotic giants is essential to advancing our understanding of these issues but unfortunately reliably determinations exist only in a few cases. We perform a program for detailed chemical composition analysis in over 30 symbiotic giants, based on the high resolution, near-IR spectra, obtained with Phoenix/Gemini South spectrometer. The methods of the standard LTE analysis is used to obtain photospheric abundances of CNO and elements around iron peak. Here we present results obtained for four objects: RW Hya, SY Mus, BX Mon, and AE Ara. Our analysis revealed a significantly sub-solar metallicity (Me/H ~ -0.75) for RW Hya, a slightly sub-solar metallicities (Me/H ~ 0.2-0.3) in BX Mon and AE Ara, and a near-solar metallicity in SY Mus. 12C/13C isotopic ratios are low in all cases, ranging from ~6 to ~10.

  12. High-resolution elemental abundance analysis of the open cluster IC 4756

    NASA Astrophysics Data System (ADS)

    Ting, Yuan-Sen; De Silva, Gayandhi M.; Freeman, Kenneth C.; Parker, Stacey Jo

    2012-11-01

    We present detailed elemental abundances of 12 subgiants in the open cluster IC 4756 including Na, Al, Mg, Si, Ca, Ti, Cr, Ni, Fe, Zn and Ba. We measure the cluster to have [Fe/H] = -0.01 ± 0.10. Most of the measured star-to-star [X/H] abundance variation is below σ < 0.03, as expected from a coeval stellar population preserving natal abundance patterns, supporting the use of elemental abundances as a probe to reconstruct dispersed clusters. We find discrepancies between Cr I and Cr II abundances as well as between Ti I and Ti II abundances, where the ionized abundances are larger by about 0.2 dex. This follows other such studies which demonstrate the effects of overionization in cool stars. IC 4756 are supersolar in Mg, Si, Na and Al, but are solar in the other elements. The fact that IC 4756 is supersolar in some α-elements (Mg, Si) but solar in the others (Ca, Ti) suggests that the production of α-elements is not simply one dimensional and could be exploited for chemical tagging.

  13. High-resolution abundance analysis of very metal-poor r-I stars

    NASA Astrophysics Data System (ADS)

    Siqueira Mello, C.; Hill, V.; Barbuy, B.; Spite, M.; Spite, F.; Beers, T. C.; Caffau, E.; Bonifacio, P.; Cayrel, R.; François, P.; Schatz, H.; Wanajo, S.

    2014-05-01

    Context. Moderately r-process-enriched stars (r-I; +0.3 ≤ [Eu/Fe] ≤ +1.0) are at least four times as common as those that are greatly enriched in r-process elements (r-II; [Eu/Fe] > +1.0), and the abundances in their atmospheres are important tools for obtaining a better understanding of the nucleosynthesis processes responsible for the origin of the elements beyond the iron peak. Aims: The main aim of this work is to derive abundances for a sample of seven metal-poor stars with -3.4 ≤ [Fe/H] ≤ -2.4 classified as r-I stars, to understand the role of these stars for constraining the astrophysical nucleosynthesis event(s) that is (are) responsible for the production of the r-process, and to investigate whether they differ, in any significant way, from the r-II stars. Methods: We carried out a detailed abundance analysis based on high-resolution spectra obtained with the VLT/UVES spectrograph, using spectra in the wavelength ranges 3400-4500 Å, 6800-8200 Å, and 8700-10 000 Å, with resolving power R ~ 40 000 (blue arm) and R ~ 55 000 (red arm). The OSMARCS LTE 1D model atmosphere grid was employed, along with the spectrum synthesis code Turbospectrum. Results: We have derived abundances of the light elements Li, C, and N, the α-elements Mg, Si, S, Ca, and Ti, the odd-Z elements Al, K, and Sc, the iron-peak elements V, Cr, Mn, Fe, Co, and Ni, and the trans-iron elements from the first peak (Sr, Y, Zr, Mo, Ru, and Pd), the second peak (Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb), the third peak (Os and Ir, as upper limits), and the actinides (Th) regions. The results are compared with values for these elements for r-II and "normal" very and extremely metal-poor stars reported in the literature, ages based on radioactive chronometry are explored using different models, and a number of conclusions about the r-process and the r-I stars are presented. Hydrodynamical models were used for some elements, and general behaviors for the 3D corrections

  14. Statistical analysis from recent abundance determinations in HgMn stars

    NASA Astrophysics Data System (ADS)

    Ghazaryan, S.; Alecian, G.

    2016-04-01

    To better understand the hot chemically peculiar group of HgMn stars, we have considered a compilation of a large number of recently published data obtained for these stars from spectroscopy. We compare these data to the previous compilation by Smith (1996). We confirm the main trends of the abundance peculiarities, namely the increasing overabundances with increasing atomic number of heavy elements, and their large spread from star to star. For all the measured elements, we have looked for a correlations between abundances and effective temperature (Teff). In addition to the known correlation for Mn, some other elements are found to show some connection between their abundances and Teff. We have also checked if multiplicity is a determinant parameter for abundance peculiarities determined for these stars. A statistical analysis using a Kolmogorov-Smirnov test shows that the abundances' anomalies in the atmosphere of HgMn stars do not present significant dependence on the multiplicity.

  15. Statistical analysis from recent abundance determinations in HgMn stars

    NASA Astrophysics Data System (ADS)

    Ghazaryan, S.; Alecian, G.

    2016-08-01

    To better understand the hot chemically peculiar group of HgMn stars, we have considered a compilation of a large number of recently published data obtained for these stars from spectroscopy. We compare these data to the previous compilation by Smith. We confirm the main trends of the abundance peculiarities, namely the increasing overabundances with increasing atomic number of heavy elements, and their large spread from star to star. For all the measured elements, we have looked for correlations between abundances and effective temperature (Teff). In addition to the known correlation for Mn, some other elements are found to show some connection between their abundances and Teff. We have also checked if multiplicity is a determinant parameter for abundance peculiarities determined for these stars. A statistical analysis using a Kolmogorov-Smirnov test shows that the abundances anomalies in the atmosphere of HgMn stars do not present significant dependence on the multiplicity.

  16. An efficient extraction method to enhance analysis of low abundant proteins from soybean seed.

    PubMed

    Natarajan, Savithiry S; Krishnan, Hari B; Lakshman, Sukla; Garrett, Wesley M

    2009-11-15

    Large amounts of the major storage proteins, beta-conglycinin and glycinin, in soybean (Glycine max) seeds hinder the isolation and characterization of less abundant seed proteins. We investigated whether isopropanol extraction could facilitate resolution of the low abundant proteins, different from the main storage protein fractions, in one-dimensional polyacrylamide gel electrophoresis (1D-PAGE) and two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). 1D-PAGE of proteins extracted by different concentrations (10%, 20%, 30%, 40%, 50%, 60%, 70% and 80%) of isopropanol showed that greater than 30% isopropanol was suitable for preferential enrichment of low abundant proteins. Analysis of 2D-PAGE showed that proteins which were less abundant or absent by the conventional extraction procedure were clearly seen in the 40% isopropanol extracts. Increasing isopropanol concentration above 40% resulted in a decrease in the number of less abundant protein spots. We have identified a total of 107 protein spots using matrix-assisted laser desorption/ionization time of flight mass spectrophotometry (MALDI-TOF-MS) and liquid chromatography-mass spectrometry (LC-MS/MS). Our results suggest that extraction of soybean seed powder with 40% isopropanol enriches lower abundance proteins and is a suitable method for 2D-PAGE separation and identification. This methodology could potentially allow the extraction and characterization of low abundant proteins of other legume seeds containing highly abundant storage proteins. PMID:19651100

  17. Genomic analysis of membrane protein families: abundance and conserved motifs

    PubMed Central

    Liu, Yang; Engelman, Donald M; Gerstein, Mark

    2002-01-01

    Background Polytopic membrane proteins can be related to each other on the basis of the number of transmembrane helices and sequence similarities. Building on the Pfam classification of protein domain families, and using transmembrane-helix prediction and sequence-similarity searching, we identified a total of 526 well-characterized membrane protein families in 26 recently sequenced genomes. To this we added a clustering of a number of predicted but unclassified membrane proteins, resulting in a total of 637 membrane protein families. Results Analysis of the occurrence and composition of these families revealed several interesting trends. The number of assigned membrane protein domains has an approximately linear relationship to the total number of open reading frames (ORFs) in 26 genomes studied. Caenorhabditis elegans is an apparent outlier, because of its high representation of seven-span transmembrane (7-TM) chemoreceptor families. In all genomes, including that of C. elegans, the number of distinct membrane protein families has a logarithmic relation to the number of ORFs. Glycine, proline, and tyrosine locations tend to be conserved in transmembrane regions within families, whereas isoleucine, valine, and methionine locations are relatively mutable. Analysis of motifs in putative transmembrane helices reveals that GxxxG and GxxxxxxG (which can be written GG4 and GG7, respectively; see Materials and methods) are among the most prevalent. This was noted in earlier studies; we now find these motifs are particularly well conserved in families, however, especially those corresponding to transporters, symporters, and channels. Conclusions We carried out a genome-wide analysis on patterns of the classified polytopic membrane protein families and analyzed the distribution of conserved amino acids and motifs in the transmembrane helix regions in these families. PMID:12372142

  18. A landscape analysis of cougar distribution and abundance in Montana, USA.

    PubMed

    Riley, S J; Malecki, R A

    2001-09-01

    Recent growth in the distribution and abundance of cougars (Puma concolor) throughout western North America has created opportunities, challenges, and problems for wildlife managers and raises questions about what factors affect cougar populations. We present an analysis of factors thought to affect cougar distribution and abundance across the broad geographical scales on which most population management decisions are made. Our objectives were to: (1) identify and evaluate landscape parameters that can be used to predict the capability of habitats to support cougars, and (2) evaluate factors that may account for the recent expansion in cougar numbers. Habitat values based on terrain ruggedness and forested cover explained 73% of the variation in a cougar abundance index. Indices of cougar abundance also were spatially and temporally correlated with ungulate abundance. An increase in the number and total biomass of ungulate prey species is hypothesized to account for recent increases in cougars. Cougar populations in Montana are coping with land development by humans when other components of habitat and prey populations are sufficient. Our analysis provides a better understanding of what may have influenced recent growth in cougar distribution and abundance in Montana and, when combined with insights about stakeholder acceptance capacity, offers a basis for cougar management at broad scales. Long-term conservation of cougars necessitates a better understanding of ecosystem functions that affect prey distribution and abundance, more accurate estimates of cougar populations, and management abilities to integrate these components with human values. PMID:11531235

  19. Ion Mobility Mass Spectrometry Direct Isotope Abundance Analysis

    SciTech Connect

    Manuel J. Manard, Stephan Weeks, Kevin Kyle

    2010-05-27

    The nuclear forensics community is currently engaged in the analysis of illicit nuclear or radioactive material for the purposes of non-proliferations and attribution. One technique commonly employed for gathering nuclear forensics information is isotope analysis. At present, the state-of-the-art methodology for obtaining isotopic distributions is thermal ionization mass spectrometry (TIMS). Although TIMS is highly accurate at determining isotope distributions, the technique requires an elementally pure sample to perform the measurement. The required radiochemical separations give rise to sample preparation times that can be in excess of one to two weeks. Clearly, the nuclear forensics community is in need of instrumentation and methods that can expedite their decision making process in the event of a radiological release or nuclear detonation. Accordingly, we are developing instrumentation that couples a high resolution IM drift cell to the front end of a MS. The IM cell provides a means of separating ions based upon their collision cross-section and mass-to-charge ratio (m/z). Two analytes with the same m/z, but with different collision cross-sections (shapes) would exit the cell at different times, essentially enabling the cell to function in a similar manner to a gas chromatography (GC) column. Thus, molecular and atomic isobaric interferences can be effectively removed from the ion beam. The mobility selected chemical species could then be introduced to a MS for high-resolution mass analysis to generate isotopic distributions of the target analytes. The outcome would be an IM/MS system capable of accurately measuring isotopic distributions while concurrently eliminating isobaric interferences and laboratory radiochemical sample preparation. The overall objective of this project is developing instrumentation and methods to produce near real-time isotope distributions with a modular mass spectrometric system that performs the required gas-phase chemistry and

  20. Spectral analysis and abundances of the post-HB star HD 76431

    NASA Astrophysics Data System (ADS)

    Khalack, V.; Yameogo, B.; LeBlanc, F.; Fontaine, G.; Green, E.; Van Grootel, V.; Petit, P.

    2014-12-01

    HD 76431 is a slow rotating post-HB star that shows an underabundance of helium by 0.5 dex relative to the solar value. These observational facts suggest that atomic diffusion could be active in its atmosphere. We have used the MMT and Bok spectra to estimate the atmospheric parameters of the target star using the model atmospheres and synthetic spectra calculated with TLUSTY and SYNSPEC. The derived values of the effective temperature, surface gravity, and helium abundance are consistent with those obtained by Ramspeck et al. It appears that non-local thermodynamic equilibrium (NLTE) effects are not important for HD 76431. We have used Stokes I spectra from ESPaDOnS at CFHT to perform an abundance analysis and a search for observational evidence of vertical stratification of the abundance of certain elements. The results of our abundance analysis are in good agreement with previously published data with respect to average abundances. Our numerical simulations show that carbon and nitrogen reveal signatures of vertical abundance stratification in the atmosphere of HD 76431. It appears that the carbon abundance increases towards the deeper atmospheric layers. Nitrogen also shows a similar behaviour, but in deeper atmospheric layers we obtain a significant dispersion for the estimates of its abundance. To our knowledge, this is the first demonstration of vertical abundance stratification of metals in a post-HB star and up to now it is the hottest star to show such stratification features. We also report the detection of two Si III and one Ti III emission lines in the spectra of HD 76431 that were not detected in previous studies.

  1. Primordial black holes as a novel probe of primordial gravitational waves. II. Detailed analysis

    NASA Astrophysics Data System (ADS)

    Nakama, Tomohiro; Suyama, Teruaki

    2016-08-01

    Recently we have proposed a novel method to probe primordial gravitational waves from upper bounds on the abundance of primordial black holes (PBHs). When the amplitude of primordial tensor perturbations generated in the early Universe is fairly large, they induce substantial scalar perturbations due to their second-order effects. If these induced scalar perturbations are too large when they reenter the horizon, then PBHs are overproduced, their abundance exceeding observational upper limits. That is, primordial tensor perturbations on superhorizon scales can be constrained from the absence of PBHs. In our recent paper we have only shown simple estimations of these new constraints, and hence in this paper, we present detailed derivations, solving the Einstein equations for scalar perturbations induced at second order in tensor perturbations. We also derive an approximate formula for the probability density function of induced density perturbations, necessary to relate the abundance of PBHs to the primordial tensor power spectrum, assuming primordial tensor perturbations follow Gaussian distributions. Our new upper bounds from PBHs are compared with other existing bounds obtained from big bang nucleosynthesis, cosmic microwave background, LIGO/Virgo and pulsar timing arrays.

  2. Detailed analysis of low energy plasma data under the Voyager Uranus data analysis program

    NASA Technical Reports Server (NTRS)

    Mcnutt, Ralph L., Jr.; Belcher, John W.; Bagenal, Frances; Richardson, John D.

    1992-01-01

    Research effort included the PLS data analysis program where modifications to the data fitting procedure and elimination of possible noise and electron contamination were made. The analysis code corrections were used in checking the Neptune data gathered during the Voyager 2 encounter and for analyzing selected plasma spectra from the warm Io torus. A major task accomplished was the summary of Uranus-related research in the U.S. National Report to the International Union of Geodesy and Geophysics for the 1987 - 1990 quadrennium. A limited amount of work was accomplished on assessing the Pedersen conductivity of the ionosphere and comparing it with inferred values from shielding by the Uranian ring current. Under this grant there has been a great deal of effort expended on identifying and classifying plasma waves and oscillations in the magnetosheath and solar wind downstream from Uranus. Large amplitude oscillations in plasma parameters are found in the magnetosheath, with density changes of up to a factor of ten occurring on times scales of minutes. New algorithms developed for analyzing the inbound bow shock crossing of Neptune will probably be applied to a more detailed analysis of the Uranus shock in the near future.

  3. The Advanced Spectral Library (ASTRAL): Abundance Analysis of the CP Star HR 465

    NASA Astrophysics Data System (ADS)

    Carpenter, Kenneth G.; Nielsen, Krister E.; Kober, Gladys V.

    2016-01-01

    We present the results of a spectrum analysis of the prototypical A-type magnetic CP star HR465. Synthetic spectra, using an non-LTE atmosphere model, were generated to fit high-resolution ultraviolet spectra (1200-3100 A) obtained as a part of the "Advanced Spectral Library (ASTRAL) Project: Hot Stars" program (GO-13346: Ayres PI). The ultraviolet data were supplemented by high resolution optical data recorded at the Nordic Optical Telescope with the SOFIN spectrograph. The optical data was used as a complement to the high line density ultraviolet spectrum and primarily used to derive accurate iron-group element abundances.HR 465 has previously been analyzed using IUE spectra. We revisit the object with this high quality data. Large parts of the spectrum have been synthesized with an ATLAS model (Teff=10750K, logg=4.0) and we present abundance results for more than 50 elements. We can confirm some of the abundance characteristics previously derived from IUE data, where elements heavier than Z=30 show significant abundance enhancements compared to solar values, while some of the lighter elements show abundance deficiencies. We will place these results in context of other AP stars, and the large number of element abundances will also help us to put some constraint on stellar abundance and evolution theories.

  4. Metabolome analysis and pathway abundance profiling of Yarrowia lipolytica cultivated on different carbon sources.

    PubMed

    Zhao, Chen; Gu, Deqing; Nambou, Komi; Wei, Liujing; Chen, Jun; Imanaka, Tadayuki; Hua, Qiang

    2015-07-20

    Yarrowia lipolytica, a model microorganism of oleaginous yeasts with developed sophisticated genetic tools, is able to metabolize a wide range of substrates and accumulate large amounts of lipids. However, there is a lack of literature reporting the metabolic characteristics of Y. lipolytica metabolizing these substrates in a systematic view. In this study, Y. lipolytica was cultivated on a variety of carbon sources, among which cell growth and production characteristics on two representative substrates (glucose and oleic acid) were investigated in detail at metabolomic level. Metabolic pathway abundance was computed to interpret the metabolome data in a straightforward way. The results showed that most pathway abundances decreased in the shift from growth to production phase. Specifically, when cultivated on glucose, abundances of twelve pathways decreased markedly between the growth and lipid production phases, while thirteen pathways reduced and only three pathways increased significantly in abundances on oleic acid. In comparison, for the same cultivation phase only a few pathways exhibited significant changes between glucose-grown and oleic acid-grown cells. This study revealed that the pathway abundance could be used to effectively show the activity changes of pathways, providing a new perspective to employ metabolomics data for understanding cell metabolism and enhancing the production of target metabolites. PMID:25912211

  5. Exoproteome analysis reveals higher abundance of proteins linked to alkaline stress in persistent Listeria monocytogenes strains.

    PubMed

    Rychli, Kathrin; Grunert, Tom; Ciolacu, Luminita; Zaiser, Andreas; Razzazi-Fazeli, Ebrahim; Schmitz-Esser, Stephan; Ehling-Schulz, Monika; Wagner, Martin

    2016-02-01

    surface virulence associated protein SvpA. Furthermore proteins involved in cell wall modification, such as the lipoteichonic acid primase LtaP and the N-acetylmuramoyl-l-alanine amidase (Lmo2591) are more abundant in EGDe than in the persistent strains and could indirectly contribute to virulence. In conclusion this study provides information about a set of proteins that could potentially support survival of L. monocytogenes in abiotic niches in food processing environments. Based on these data, a more detailed analysis of the role of the identified proteins under stresses mimicking conditions in food producing environment is essential for further elucidate the mechanism of the phenomenon of persistence of L. monocytogenes. PMID:26594790

  6. Visualized numerical assessment for near infrared diffuse optical tomography with contrast-and-size detail analysis

    NASA Astrophysics Data System (ADS)

    Chen, Liang-Yu; Pan, Min-Cheng; Pan, Min-Chun

    2013-01-01

    The purpose of this study is to propose an objective contrast-and-size detail (CSD) analysis for near infrared diffuse optical tomography (NIR DOT), of which the concept is derived from the subjective contrast detail (CD) analysis. We define a measure for numerical CSD analysis based on the resolution estimation of contrast and size. Following that, the contrast-and-size map of resolution can be calculated and displayed for each corresponding image in the map; furthermore, a CSD resolution curve can be plotted by calculating the average value of the projection corresponding to the physical quantity/axis (size or contrast). To provide some worked examples about the proposed CSD analysis evaluating the imaging performance of different reconstruction methods, Tikhonov regularization and edge-preserving regularization with different weighting functions were employed. Results suggested that using edge-preserving regularization with the generalized Lorentzian weighting function is the most attractive for the estimation of absorption-coefficient images.

  7. 78 FR 47317 - Intent To Conduct a Detailed Economic Impact Analysis

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-05

    ... From the Federal Register Online via the Government Publishing Office EXPORT-IMPORT BANK OF THE UNITED STATES Intent To Conduct a Detailed Economic Impact Analysis This notice is to inform the public that the Export-Import Bank of the United States has received an application for a loan guarantee...

  8. 78 FR 69669 - Intent To Conduct a Detailed Economic Impact Analysis

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... From the Federal Register Online via the Government Publishing Office EXPORT-IMPORT BANK Intent To Conduct a Detailed Economic Impact Analysis This notice is to inform the public that the Export-Import... comments on this transaction by email to economic.impact@exim.gov or by mail to 811 Vermont Avenue...

  9. NEON AND CNO ABUNDANCES FOR EXTREME HELIUM STARS-A NON-LTE ANALYSIS

    SciTech Connect

    Pandey, Gajendra; Lambert, David L. E-mail: dll@astro.as.utexas.edu

    2011-02-01

    A non-LTE (NLTE) abundance analysis was carried out for three extreme helium stars (EHes): BD+10{sup 0} 2179, BD-9{sup 0} 4395, and LS IV+6{sup 0} 002, from their optical spectra with NLTE model atmospheres. NLTE TLUSTY model atmospheres were computed with H, He, C, N, O, and Ne treated in NLTE. Model atmosphere parameters were chosen from consideration of fits to observed He I line profiles and ionization equilibria of C and N ions. The program SYNSPEC was then used to determine the NLTE abundances for Ne as well as H, He, C, N, and O. LTE neon abundances from Ne I lines in the EHes: LSE 78, V1920 Cyg, HD 124448, and PV Tel, are derived from published models and an estimate of the NLTE correction applied to obtain the NLTE Ne abundance. We show that the derived abundances of these key elements, including Ne, are well matched with semi-quantitative predictions for the EHe resulting from a cold merger (i.e., no nucleosynthesis during the merger) of an He white dwarf with a C-O white dwarf.

  10. Detailed requirements document for the integrated structural analysis system, phase B

    NASA Technical Reports Server (NTRS)

    Rainey, J. A.

    1976-01-01

    The requirements are defined for a software system entitled integrated Structural Analysis System (ISAS) Phase B which is being developed to provide the user with a tool by which a complete and detailed analysis of a complex structural system can be performed. This software system will allow for automated interface with numerous structural analysis batch programs and for user interaction in the creation, selection, and validation of data. This system will include modifications to the 4 functions developed for ISAS, and the development of 25 new functions. The new functions are described.

  11. Maturation trend in oils and asphalts of the Jordan Rift: Utilization of detailed vanadylporphyrin analysis

    NASA Astrophysics Data System (ADS)

    Aizenshtat, Zeev; Sundararaman, Padmanabhan

    1989-12-01

    A comparison of analytical methods for porphyrin analysis shows that high-performance liquid chromatography (HPLC) of intact vanadylporphyrins is more advantageous than, or superior to, mass spectral methods and is suited for routine analysis. HPLC has a higher resolving power compared with probe mass spectrometry. Detailed HPLC analysis of the vanadylporphyrins isolated from asphalts and oils from the Dead Sea area shows that the asphalts are products of early generation from an immature source rock. The light oils, Massada oil and Zuk Tamror, are more mature than the asphalts.

  12. Abundance analysis of an extended sample of open clusters: A search for chemical inhomogeneities

    NASA Astrophysics Data System (ADS)

    Reddy, Arumalla B. S.; Giridhar, Sunetra; Lambert, David L.

    We have initiated a program to explore the presence of chemical inhomogeneities in the Galactic disk using the open clusters as ideal probes. We have analyzed high-dispersion echelle spectra (R ≥ 55,000) of red giant members for eleven open clusters to derive abundances for many elements. The membership to the cluster has been confirmed through their radial velocities and proper motions. The spread in temperatures and gravities being very small among the red giants, nearly the same stellar lines were employed thereby reducing the random errors. The errors of average abundance for the cluster were generally in 0.02 to 0.07 dex range. Our present sample covers galactocentric distances of 8.3 to 11.3 kpc and an age range of 0.2 to 4.3 Gyrs. Our earlier analysis of four open clusters (Reddy A.B.S. et al., 2012, MNRAS, 419,1350) indicate that abundances relative to Fe for elements from Na to Eu are equal within measurement uncertainties to published abundances for thin disk giants in the field. This supports the view that field stars come from disrupted open clusters. In the enlarged sample of eleven open clusters we find cluster to cluster abundance variations for some s- and r- process elements, with certain elements such as Zr and Ba showing large variation. These differences mark the signatures that these clusters had formed under different environmental conditions (Type II SN, Type Ia SN, AGB stars or a mixture of any of these) unique to the time and site of formation. These eleven clusters support the widely held impression that there is an abundance gradient such that the metallicity [Fe/H] at the solar galactocentric distance decreases outwards at about -0.1 dex per kpc.

  13. Detailed interpretation and analysis of selected corn blight watch data sets

    NASA Technical Reports Server (NTRS)

    Nalepka, R. F.; Morgenstern, J. P.; Brown, W. L.

    1972-01-01

    A detailed interpretation and analysis of selected corn blight data set was undertaken in order to better define the present capabilities and limitations of agricultural remote multispectral sensing and automatic processing techniques and to establish the areas of investigation needing futher attention in the development of operational survey systems. While the emphasis of this effort was directed toward the detection of various corn blight levels, problems related to the more general task of crop identification were also investigated. Since the analog recognition computer (SPARC) was fully committed to the more routine aspects of processing and since the detailed interpretation and analysis required more in the way of quantitative information, the CDC 1604 digital computer was employed.

  14. Meta-Analysis of the Effects of Predation on Animal Prey Abundance: Evidence from UK Vertebrates

    PubMed Central

    Holt, Alison R.; Davies, Zoe G.; Tyler, Claire; Staddon, Samantha

    2008-01-01

    Background Controlling vertebrate predators is one of the most widespread forms of wildlife management and it continues to cause conflict between stakeholders worldwide. It is important for managers and policy-makers to make decisions on this issue that are based on the best available scientific evidence. Therefore, it is first important to understand if there is indeed an impact of vertebrate predators on prey, and then to quantify this impact. Methodology/Principal Findings Using the UK as a case study, we use a meta-analytical approach to review the available evidence to assess the effect of vertebrate predation on animal prey abundance. We find a significant effect of predators on prey abundance across our studies. On average, there is a 1.6 fold increase in prey abundance in the absence of predation. However, we show significant heterogeneity in effect sizes, and discuss how the method of predator control, whether the predator is native or non-native, and aspects of study design, may be potential causes. Conclusions/Significance Our results allow some cautious policy recommendations to be made regarding the management of predator and prey populations. Meta-analysis is an important tool for understanding general patterns in the effect of predators on prey abundance across studies. Such an approach is especially valuable where management decisions need to be made in the absence of site-specific information. PMID:18545690

  15. Detailed Uncertainty Analysis for Ares I Ascent Aerodynamics Wind Tunnel Database

    NASA Technical Reports Server (NTRS)

    Hemsch, Michael J.; Hanke, Jeremy L.; Walker, Eric L.; Houlden, Heather P.

    2008-01-01

    A detailed uncertainty analysis for the Ares I ascent aero 6-DOF wind tunnel database is described. While the database itself is determined using only the test results for the latest configuration, the data used for the uncertainty analysis comes from four tests on two different configurations at the Boeing Polysonic Wind Tunnel in St. Louis and the Unitary Plan Wind Tunnel at NASA Langley Research Center. Four major error sources are considered: (1) systematic errors from the balance calibration curve fits and model + balance installation, (2) run-to-run repeatability, (3) boundary-layer transition fixing, and (4) tunnel-to-tunnel reproducibility.

  16. Trelliscope: A System for Detailed Visualization in Analysis of Large Complex Data

    SciTech Connect

    Hafen, Ryan P.; Gosink, Luke J.; McDermott, Jason E.; Rodland, Karin D.; Kleese-Van Dam, Kerstin; Cleveland, William S.

    2013-12-01

    Visualization plays a critical role in the statistical model building and data analysis process. Data analysts, well-versed in statistical and machine learning methods, visualize data to hypothesize and validate models. These analysts need flexible, scalable visualization tools that are not decoupled from their analysis environment. In this paper we introduce Trelliscope, a visualization framework for statistical analysis of large complex data. Trelliscope extends Trellis, an effective visualization framework that divides data into subsets and applies a plotting method to each subset, arranging the results in rows and columns of panels. Trelliscope provides a way to create, arrange and interactively view panels for very large datasets, enabling flexible detailed visualization for data of any size. Scalability is achieved using distributed computing technologies coupled with . We discuss the underlying principles, design, and scalable architecture of Trelliscope, and illustrate its use on three analysis projects in the domains of proteomics, high energy physics, and power systems engineering.

  17. Proteomic analysis of an unculturable bacterial endosymbiont (Blochmannia) reveals high abundance of chaperonins and biosynthetic enzymes

    PubMed Central

    Fan, Yongliang; Thompson, J. Will; Dubois, Laura G.; Moseley, M. Arthur; Wernegreen, Jennifer J.

    2013-01-01

    Many insect groups have coevolved with bacterial endosymbionts that live within specialized host cells. As a salient example, ants in the tribe Camponotini rely on Blochmannia, an intracellular bacterial mutualist that synthesizes amino acids and recycles nitrogen for the host. We performed a shotgun, label-free, LC/MS/MS quantitative proteomic analysis to investigate the proteome of Blochmannia associated with Camponotus chromaiodes. We identified more than 330 Blochmannia proteins, or 54% coverage of the predicted proteome, as well as 244 Camponotus proteins. Using the average intensity of the top 3 “best flier” peptides along with spiking of a surrogate standard at a known concentration, we estimated the concentration (fmol/μg) of those proteins with confident identification. The estimated dynamic range of Blochmannia protein abundance spanned three orders of magnitude and covered diverse functional categories, with particularly high representation of metabolism, information transfer, and chaperones. GroEL, the most abundant protein, totaled 6% of Blochmannia protein abundance. Biosynthesis of essential amino acids, fatty acids, and nucleotides, and sulfate assimilation had disproportionately high coverage in the proteome, further supporting a nutritional role of the symbiosis. This first quantitative proteomic analysis of an ant endosymbiont illustrates a promising approach to study the functional basis of intimate symbioses. PMID:23205679

  18. A detailed analysis of the erythropoietic control system in the human, squirrel, monkey, rat and mouse

    NASA Technical Reports Server (NTRS)

    Nordheim, A. W.

    1985-01-01

    The erythropoiesis modeling performed in support of the Body Fluid and Blood Volume Regulation tasks is described. The mathematical formulation of the species independent model, the solutions to the steady state and dynamic versions of the model, and the individual species specific models for the human, squirrel monkey, rat and mouse are outlined. A detailed sensitivity analysis of the species independent model response to parameter changes and how those responses change from species to species is presented. The species to species response to a series of simulated stresses directly related to blood volume regulation during space flight is analyzed.

  19. Detailed analysis and test correlation of a stiffened composite wing panel

    NASA Technical Reports Server (NTRS)

    Davis, D. Dale, Jr.

    1991-01-01

    Nonlinear finite element analysis techniques are evaluated by applying them to a realistic aircraft structural component. A wing panel from the V-22 tiltrotor aircraft is chosen because it is a typical modern aircraft structural component for which there is experimental data for comparison of results. From blueprints and drawings supplied by the Bell Helicopter Textron Corporation, a very detailed finite element model containing 2284 9-node Assumed Natural-Coordinate Strain (ANS) elements was generated. A novel solution strategy which accounts for geometric nonlinearity through the use of corotating element reference frames and nonlinear strain displacements relations is used to analyze this detailed model. Results from linear analyses using the same finite element model are presented in order to illustrate the advantages and costs of the nonlinear analysis as compared with the more traditional linear analysis. Strain predictions from both the linear and nonlinear stress analyses are shown to compare well with experimental data up through the Design Ultimate Load (DUL) of the panel. However, due to the extreme nonlinear response of the panel, the linear analysis was not accurate at loads above the DUL. The nonlinear analysis more accurately predicted the strain at high values of applied load, and even predicted complicated nonlinear response characteristics, such as load reversals, at the observed failure load of the test panel. In order to understand the failure mechanism of the panel, buckling and first ply failure analyses were performed. The buckling load was 17 percent above the observed failure load while first ply failure analyses indicated significant material damage at and below the observed failure load.

  20. Spectral Properties of Cool Stars: Extended Abundance Analysis of 1,617 Planet-search Stars

    NASA Astrophysics Data System (ADS)

    Brewer, John M.; Fischer, Debra A.; Valenti, Jeff A.; Piskunov, Nikolai

    2016-08-01

    We present a catalog of uniformly determined stellar properties and abundances for 1,617 F, G, and K stars using an automated spectral synthesis modeling procedure. All stars were observed using the HIRES spectrograph at Keck Observatory. Our procedure used a single line list to fit model spectra to observations of all stars to determine effective temperature, surface gravity, metallicity, projected rotational velocity, and the abundances of 15 elements (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, and Y). Sixty percent of the sample had Hipparcos parallaxes and V-band photometry, which we combined with the spectroscopic results to obtain mass, radius, and luminosity. Additionally, we used the luminosity, effective temperature, metallicity and α-element enhancement to interpolate in the Yonsei–Yale isochrones to derive mass, radius, gravity, and age ranges for those stars. Finally, we determined new relations between effective temperature and macroturbulence for dwarfs and subgiants. Our analysis achieved precisions of 25 K in {T}{eff}, 0.01 dex in [M/H], 0.028 dex for {log}g, and 0.5 km s‑1 in v\\sin i based on multiple observations of the same stars. The abundance results were similarly precise, between ∼0.01 and ∼0.04 dex, though trends with respect to {T}{eff} remained for which we derived empirical corrections. The trends, though small, were much larger than our uncertainties and are shared with published abundances. We show that changing our model atmosphere grid accounts for most of the trend in [M/H] between 5000 and 5500 K, indicating a possible problem with the atmosphere models or opacities.

  1. Spectral Properties of Cool Stars: Extended Abundance Analysis of 1,617 Planet-search Stars

    NASA Astrophysics Data System (ADS)

    Brewer, John M.; Fischer, Debra A.; Valenti, Jeff A.; Piskunov, Nikolai

    2016-08-01

    We present a catalog of uniformly determined stellar properties and abundances for 1,617 F, G, and K stars using an automated spectral synthesis modeling procedure. All stars were observed using the HIRES spectrograph at Keck Observatory. Our procedure used a single line list to fit model spectra to observations of all stars to determine effective temperature, surface gravity, metallicity, projected rotational velocity, and the abundances of 15 elements (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, and Y). Sixty percent of the sample had Hipparcos parallaxes and V-band photometry, which we combined with the spectroscopic results to obtain mass, radius, and luminosity. Additionally, we used the luminosity, effective temperature, metallicity and α-element enhancement to interpolate in the Yonsei–Yale isochrones to derive mass, radius, gravity, and age ranges for those stars. Finally, we determined new relations between effective temperature and macroturbulence for dwarfs and subgiants. Our analysis achieved precisions of 25 K in {T}{eff}, 0.01 dex in [M/H], 0.028 dex for {log}g, and 0.5 km s‑1 in v\\sin i based on multiple observations of the same stars. The abundance results were similarly precise, between ˜0.01 and ˜0.04 dex, though trends with respect to {T}{eff} remained for which we derived empirical corrections. The trends, though small, were much larger than our uncertainties and are shared with published abundances. We show that changing our model atmosphere grid accounts for most of the trend in [M/H] between 5000 and 5500 K, indicating a possible problem with the atmosphere models or opacities.

  2. KNOW YOUR NEIGHBORHOOD: A DETAILED MODEL ATMOSPHERE ANALYSIS OF NEARBY WHITE DWARFS

    SciTech Connect

    Giammichele, N.; Bergeron, P.; Dufour, P. E-mail: pierre.bergeron@astro.umontreal.ca

    2012-04-01

    We present improved atmospheric parameters of nearby white dwarfs lying within 20 pc of the Sun. The aim of the current study is to obtain the best statistical model of the least-biased sample of the white dwarf population. A homogeneous analysis of the local population is performed combining detailed spectroscopic and photometric analyses based on improved model atmosphere calculations for various spectral types including DA, DB, DC, DQ, and DZ stars. The spectroscopic technique is applied to all stars in our sample for which optical spectra are available. Photometric energy distributions, when available, are also combined to trigonometric parallax measurements to derive effective temperatures, stellar radii, as well as atmospheric compositions. A revised catalog of white dwarfs in the solar neighborhood is presented. We provide, for the first time, a comprehensive analysis of the mass distribution and the chemical distribution of white dwarf stars in a volume-limited sample.

  3. Know Your Neighborhood: A Detailed Model Atmosphere Analysis of Nearby White Dwarfs

    NASA Astrophysics Data System (ADS)

    Giammichele, N.; Bergeron, P.; Dufour, P.

    2012-04-01

    We present improved atmospheric parameters of nearby white dwarfs lying within 20 pc of the Sun. The aim of the current study is to obtain the best statistical model of the least-biased sample of the white dwarf population. A homogeneous analysis of the local population is performed combining detailed spectroscopic and photometric analyses based on improved model atmosphere calculations for various spectral types including DA, DB, DC, DQ, and DZ stars. The spectroscopic technique is applied to all stars in our sample for which optical spectra are available. Photometric energy distributions, when available, are also combined to trigonometric parallax measurements to derive effective temperatures, stellar radii, as well as atmospheric compositions. A revised catalog of white dwarfs in the solar neighborhood is presented. We provide, for the first time, a comprehensive analysis of the mass distribution and the chemical distribution of white dwarf stars in a volume-limited sample.

  4. Exergy analysis of an industrial-scale ultrafiltrated (UF) cheese production plant: a detailed survey

    NASA Astrophysics Data System (ADS)

    Nasiri, Farshid; Aghbashlo, Mortaza; Rafiee, Shahin

    2016-05-01

    In this study, a detailed exergy analysis of an industrial-scale ultrafiltrated (UF) cheese production plant was conducted based on actual operational data in order to provide more comprehensive insights into the performance of the whole plant and its main subcomponents. The plant included four main subsystems, i.e., steam generator (I), above-zero refrigeration system (II), Bactocatch-assisted pasteurization line (III), and UF cheese production line (IV). In addition, this analysis was aimed at quantifying the exergy destroyed in processing a known quantity of the UF cheese using the mass allocation method. The specific exergy destruction of the UF cheese production was determined at 2330.42 kJ/kg. The contributions of the subsystems I, II, III, and IV to the specific exergy destruction of the UF cheese production were computed as 1337.67, 386.18, 283.05, and 323.51 kJ/kg, respectively. Additionally, it was observed through the analysis that the steam generation system had the largest contribution to the thermodynamic inefficiency of the UF cheese production, accounting for 57.40 % of the specific exergy destruction. Generally, the outcomes of this survey further manifested the benefits of applying exergy analysis for design, analysis, and optimization of industrial-scale dairy processing plants to achieve the most cost-effective and environmentally-benign production strategies.

  5. VizieR Online Data Catalog: Elemental abundance analysis of HR 8216 (Caliskan, 2005)

    NASA Astrophysics Data System (ADS)

    Caliskan, H.

    2003-09-01

    We have performed the abundance analysis of the cool magnetic CP star HR 8216 (=HD 204411) using 2.4{AA}/mm Dominion Astrophysical Observatory Reticon exposures covering ll 3830-4770{AA} with a typical signal-to-noise ratio of 200. The spectrograms were measured interactively with the graphics computer program REDUCE. We performed a fine analysis with an ATLAS9 metal-rich model atmosphere whose predictions best matched the optical region fluxes and the Hg profile. HR 8216's anomalies are primarily an enhancement of many iron peak elements with the rare earths elements much less enhanced than for many similar cool magnetic CP stars .Using the results of the fine analysis we synthetized the spectrum. Comparison with the observed spectrum showed that agreement is better. (1 data file).

  6. Comparison of different computed radiography systems: Physical characterization and contrast detail analysis

    SciTech Connect

    Rivetti, Stefano; Lanconelli, Nico; Bertolini, Marco; Nitrosi, Andrea; Burani, Aldo; Acchiappati, Domenico

    2010-02-15

    Purpose: In this study, five different units based on three different technologies--traditional computed radiography (CR) units with granular phosphor and single-side reading, granular phosphor and dual-side reading, and columnar phosphor and line-scanning reading--are compared in terms of physical characterization and contrast detail analysis. Methods: The physical characterization of the five systems was obtained with the standard beam condition RQA5. Three of the units have been developed by FUJIFILM (FCR ST-VI, FCR ST-BD, and FCR Velocity U), one by Kodak (Direct View CR 975), and one by Agfa (DX-S). The quantitative comparison is based on the calculation of the modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE). Noise investigation was also achieved by using a relative standard deviation analysis. Psychophysical characterization is assessed by performing a contrast detail analysis with an automatic reading of CDRAD images. Results: The most advanced units based on columnar phosphors provide MTF values in line or better than those from conventional CR systems. The greater thickness of the columnar phosphor improves the efficiency, allowing for enhanced noise properties. In fact, NPS values for standard CR systems are remarkably higher for all the investigated exposures and especially for frequencies up to 3.5 lp/mm. As a consequence, DQE values for the three units based on columnar phosphors and line-scanning reading, or granular phosphor and dual-side reading, are neatly better than those from conventional CR systems. Actually, DQE values of about 40% are easily achievable for all the investigated exposures. Conclusions: This study suggests that systems based on the dual-side reading or line-scanning reading with columnar phosphors provide a remarkable improvement when compared to conventional CR units and yield results in line with those obtained from most digital detectors for radiography.

  7. ARCRAIDER. I. Detailed optical and X-ray analysis of the cooling flow cluster Z3146

    NASA Astrophysics Data System (ADS)

    Kausch, W.; Gitti, M.; Erben, T.; Schindler, S.

    2007-08-01

    We present a detailed analysis of the medium redshift (z = 0.2906) galaxy cluster Z3146 which is part of the ongoing ARCRAIDER project, a systematic search for gravitational arcs in massive clusters of galaxies. The analysis of Z3146 is based on deep optical wide field observations in the B, V and R bands obtained with the WFI@ESO2.2m, and shallow archival WFPC2@HST taken with the F606W filter, which are used for strong as well as weak lensing analyses. Additionally we have used publicly available XMM/Newton observations for a detailed X-ray analysis of Z3146. Both methods, lensing and X-ray, were used to determine the dynamical state and to estimate the total mass. We also identified four gravitational arc candidates. We find this cluster to be in a relaxed state, which is confirmed by a large cooling flow with nominal ~1600 M_⊙ per year, regular galaxy density and light distributions and a regular shape of the weak lensing mass reconstruction. The mass content derived with the different methods agrees well within 25% at r200=1661 h70-1 kpc indicating a velocity dispersion of σ_v=869+124-153 km s-1. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Institute (PID-number 8301). STScI is operated by the association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555. Also based on observations made with ESO Telescopes at the La Silla or Paranal Observatories under programme ID 68.A-02555 and 073.A-0050 and on observations with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member states and the USA (NASA).

  8. Developments in remote sensing technology enable more detailed urban flood risk analysis.

    NASA Astrophysics Data System (ADS)

    Denniss, A.; Tewkesbury, A.

    2009-04-01

    digital airborne sensors, both optical and lidar, to produce the input layer for surface water flood modelling. A national flood map product has been created. The new product utilises sophisticated modelling techniques, perfected over many years, which harness graphical processing power. This product will prove particularly valuable for risk assessment decision support within insurance/reinsurance, property/environmental, utilities, risk management and government agencies. However, it is not just the ground elevation that determines the behaviour of surface water. By combining height information (surface and terrain) with high resolution aerial photography and colour infrared imagery, a high definition land cover mapping dataset (LandBase) is being produced, which provides a precise measure of sealed versus non sealed surface. This will allows even more sophisticated modelling of flood scenarios. Thus, the value of airborne survey data can be demonstrated by flood risk analysis down to individual addresses in urban areas. However for some risks, an even more detailed survey may be justified. In order to achieve this, Infoterra is testing new 360˚ mobile lidar technology. Collecting lidar data from a moving vehicle allows each street to be mapped in very high detail, allowing precise information about the location, size and shape of features such as kerbstones, gullies, road camber and building threshold level to be captured quickly and accurately. These data can then be used to model the problem of overland flood risk at the scale of individual properties. Whilst at present it might be impractical to undertake such detailed modelling for all properties, these techniques can certainly be used to improve the flood risk analysis of key locations. This paper will demonstrate how these new high resolution remote sensing techniques can be combined to provide a new resolution of detail to aid urban flood modelling.

  9. The 2006 lava dome eruption of Merapi Volcano (Indonesia): Detailed analysis using MODIS TIR

    NASA Astrophysics Data System (ADS)

    Carr, Brett B.; Clarke, Amanda B.; Vanderkluysen, Loÿc

    2016-02-01

    Merapi is one of Indonesia's most active and dangerous volcanoes. Prior to the 2010 VEI 4 eruption, activity at Merapi during the 20th century was characterized by the growth and collapse of a series of lava domes. Periods of very slow growth were punctuated by short episodes of increased eruption rates characterized by dome collapse-generated pyroclastic density currents (PDCs). An eruptive event of this type occurred in May-June, 2006. For effusive eruptions such as this, detailed extrusion rate records are important for understanding the processes driving the eruption and the hazards presented by the eruption. We use thermal infrared (TIR) images from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on NASA's Aqua and Terra satellites to estimate extrusion rates at Merapi Volcano during the 2006 eruption using the method of Harris and Ripepe (2007). We compile a set of 75 nighttime MODIS images of the eruptive period to produce a detailed time series of thermal radiance and extrusion rate that reveal multiple phases of the 2006 eruption. These data closely correspond to the published ground-based observational record and improve observation density and detail during the eruption sequence. Furthermore, additional analysis of radiance values for thermal anomalies in Band 21 (λ = 3.959 μm) of MODIS images results in a new framework for detecting different styles of activity. We successfully discriminate among slow dome growth, rapid dome growth, and PDC-producing dome collapse. We also demonstrate a positive correlation between PDC frequency and extrusion rate, and provide evidence that extrusion rate can increase in response to external events such as dome collapses or tectonic earthquakes. This study represents a new method of documenting volcanic activity that can be applied to other similar volcanic systems.

  10. Detailed molecular analysis of the induction of the L-PK gene by glucose

    PubMed Central

    Eckert, David T.; Zhang, Pili; Collier, J. Jason; O’Doherty, Robert M.; Scott, Donald K.

    2008-01-01

    Glucose has powerful effects on gene expression and participates in the fasted to fed transition of the liver. However, the molecular mechanism of glucose-regulated gene expression has not been completely described. In the present study, we performed a detailed analysis of the molecular events of the insulin-independent glucose response of the liver-type pyruvate kinase (L-PK) gene. L-PK mRNA was increased by glucose at the transcriptional level as determined by real-time RT-PCR, mRNA stability measurements, and nuclear run-on assays. LY294002 and LY303511 inhibited the glucose response of the L-PK gene at the transcriptional level. Histones H3 and H4 associated with the L-PK gene promoter were hyperacetylated and HNF4α was constitutively bound in low and high glucose. Treatment with 20 mM glucose increased recruitment of ChREBP, additional HNF4α, and RNA polymerase II. Glucose stimulated the phosphorylation of the C terminal domain of RNA polymerase II, with increased Ser5 phosphorylation near the transcription start site and increased Ser2 phosphorylation near the termination signal. LY294002 and LY303511 blocked the recruitment of RNA polymerase II to the L-PK gene, reducing the rate of transcription. The results of these studies demonstrate fundamental details of the molecular mechanism of glucose activated gene expression. PMID:18468514

  11. Detailed analysis of surface asperity deformation mechanism in diffusion bonding of steel hollow structural components

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Li, H.; Li, M. Q.

    2016-05-01

    This study focused on the detailed analysis of surface asperity deformation mechanism in similar diffusion bonding as well as on the fabrication of high quality martensitic stainless steel hollow structural components. A special surface with regular patterns was processed to be joined so as to observe the extent of surface asperity deformation under different bonding pressures. Results showed that an undamaged hollow structural component has been obtained with full interfacial contact and the same shear strength to that of base material. Fracture surface characteristic combined with surface roughness profiles distinctly revealed the enhanced surface asperity deformation as the applied pressure increases. The influence of surface asperity deformation mechanism on joint formation was analyzed: (a) surface asperity deformation not only directly expanded the interfacial contact areas, but also released deformation heat and caused defects, indirectly accelerating atomic diffusion, then benefits to void shrinkage; (b) surface asperity deformation readily introduced stored energy difference between two opposite sides of interface grain boundary, resulting in strain induced interface grain boundary migration. In addition, the influence of void on interface grain boundary migration was analyzed in detail.

  12. Contrast-detail analysis of three flat panel detectors for digital radiography

    SciTech Connect

    Borasi, Giovanni; Samei, Ehsan; Bertolini, Marco; Nitrosi, Andrea; Tassoni, Davide

    2006-06-15

    In this paper we performed a contrast detail analysis of three commercially available flat panel detectors, two based on the indirect detection mechanism (GE Revolution XQ/i, system A, and Trixell/Philips Pixium 4600, system B) and one based on the direct detection mechanism (Hologic DirectRay DR 1000, system C). The experiment was conducted using standard x-ray radiation quality and a widely used contrast-detail phantom. Images were evaluated using a four alternative forced choice paradigm on a diagnostic-quality softcopy monitor. At the low and intermediate exposures, systems A and B gave equivalent performances. At the high dose levels, system A performed better than system B in the entire range of target sizes, even though the pixel size of system A was about 40% larger than that of system B. At all the dose levels, the performances of the system C (direct system) were lower than those of system A and B (indirect systems). Theoretical analyses based on the Perception Statistical Model gave similar predicted SNR{sub T} values corresponding to an observer efficiency of about 0.08 for systems A and B and 0.05 for system C.

  13. Mapping of replication initiation sites in human ribosomal DNA by nascent-strand abundance analysis.

    PubMed Central

    Yoon, Y; Sanchez, J A; Brun, C; Huberman, J A

    1995-01-01

    New techniques for mapping mammalian DNA replication origins are needed. We have modified the existing nascent-strand size analysis technique (L. Vassilev and E.M. Johnson, Nucleic Acids Res. 17:7693-7705, 1989) to provide an independent means of studying replication initiation sites. We call the new method nascent-strand abundance analysis. We confirmed the validity of this method with replicating simian virus 40 DNA as a model. We then applied nascent-strand abundance and nascent-strand size analyses to mapping of initiation sites in human (HeLa) ribosomal DNA (rDNA), a region previously examined exclusively by two-dimensional gel electrophoresis methods (R.D. Little, T.H.K. Platt, and C.L. Schildkraut, Mol. Cell. Biol. 13:6600-6613, 1993). Our results partly confirm those obtained by two-dimensional gel electrophoresis techniques. Both studies suggest that replication initiates at relatively high frequency a few kilobase pairs upstream of the transcribed region and that many additional low-frequency initiation sites are distributed through most of the remainder of the ribosomal DNA repeat unit. PMID:7739533

  14. Contrast to Noise Ratio and Contrast Detail Analysis in Mammography:A Monte Carlo Study

    NASA Astrophysics Data System (ADS)

    Metaxas, V.; Delis, H.; Kalogeropoulou, C.; Zampakis, P.; Panayiotakis, G.

    2015-09-01

    The mammographic spectrum is one of the major factors affecting image quality in mammography. In this study, a Monte Carlo (MC) simulation model was used to evaluate image quality characteristics of various mammographic spectra. The anode/filter combinations evaluated, were those traditionally used in mammography, for tube voltages between 26 and 30 kVp. The imaging performance was investigated in terms of Contrast to Noise Ratio (CNR) and Contrast Detail (CD) analysis, by involving human observers, utilizing a mathematical CD phantom. Soft spectra provided the best characteristics in terms of both CNR and CD scores, while tube voltage had a limited effect. W-anode spectra filtered with k-edge filters demonstrated an improved performance, that sometimes was better compared to softer x-ray spectra, produced by Mo or Rh anode. Regarding the filter material, k-edge filters showed superior performance compared to Al filters.

  15. A detailed error analysis of 13 kernel methods for protein–protein interaction extraction

    PubMed Central

    2013-01-01

    Background Kernel-based classification is the current state-of-the-art for extracting pairs of interacting proteins (PPIs) from free text. Various proposals have been put forward, which diverge especially in the specific kernel function, the type of input representation, and the feature sets. These proposals are regularly compared to each other regarding their overall performance on different gold standard corpora, but little is known about their respective performance on the instance level. Results We report on a detailed analysis of the shared characteristics and the differences between 13 current methods using five PPI corpora. We identified a large number of rather difficult (misclassified by most methods) and easy (correctly classified by most methods) PPIs. We show that kernels using the same input representation perform similarly on these pairs and that building ensembles using dissimilar kernels leads to significant performance gain. However, our analysis also reveals that characteristics shared between difficult pairs are few, which lowers the hope that new methods, if built along the same line as current ones, will deliver breakthroughs in extraction performance. Conclusions Our experiments show that current methods do not seem to do very well in capturing the shared characteristics of positive PPI pairs, which must also be attributed to the heterogeneity of the (still very few) available corpora. Our analysis suggests that performance improvements shall be sought after rather in novel feature sets than in novel kernel functions. PMID:23323857

  16. Detailed Transthoracic and Transesophageal Echocardiographic Analysis of Mitral Leaflets in Patients Undergoing Mitral Valve Repair.

    PubMed

    Ghulam Ali, Sarah; Fusini, Laura; Tamborini, Gloria; Muratori, Manuela; Gripari, Paola; Mapelli, Massimo; Zanobini, Marco; Alamanni, Francesco; Pepi, Mauro

    2016-07-01

    A recent histological study of resected scallop-P2 in mitral valve (MV) prolapse, showed that chordae tendinae may be missing or hidden in superimposed fibrous tissue of the leaflets, contributing to their thickening. This may have relevant clinical implication because detailed analysis of MV leaflets has a central role in the evaluation of patients undergoing repair. The aim of this study was to analyze MV leaflets focusing on thickness of prolapsing segments and the presence of chordal rupture (CR). We enrolled 246 patients (age 63 ± 13 years, 72 men) with isolated P2 prolapse and also 50 age-matched patients with normal MV anatomy as control group. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) were retrospectively analyzed to quantify the length and the proximal and distal thickness of both anterior (A2) and posterior (P2) MV scallops. Measurements were performed at end diastole in the standard TTE and TEE views. TTE and TEE measurements were feasible in all cases. Echocardiographically 176 patients had CR (group A), 45 had no rupture (group B), and 25 had an uncertain diagnosis (group C). All pathological groups showed thickening and elongation of involved leaflets versus normal, whereas no differences in leaflets characteristics were found among MV groups. Most patients undergoing MV repair had CR with thickening of the prolapsed segment. These findings are in agreement with recent histological studies showing superimposed fibrous tissue on MV leaflets partially including ruptured chordae. This may also explain that in cases without ruptured chordae, thickness of the leaflets is markedly increased (hidden chordae?). In conclusion, detailed analysis of MV apparatus may further improve knowledge of these patients and may influence surgical timing. PMID:27184171

  17. Patterns of Failure After MammoSite Brachytherapy Partial Breast Irradiation: A Detailed Analysis

    SciTech Connect

    Chen, Sea Dickler, Adam; Kirk, Michael; Shah, Anand; Jokich, Peter; Solmos, Gene; Strauss, Jonathan; Dowlatshahi, Kambiz; Nguyen, Cam; Griem, Katherine

    2007-09-01

    Purpose: To report the results of a detailed analysis of treatment failures after MammoSite breast brachytherapy for partial breast irradiation from our single-institution experience. Methods and Materials: Between October 14, 2002 and October 23, 2006, 78 patients with early-stage breast cancer were treated with breast-conserving surgery and accelerated partial breast irradiation using the MammoSite brachytherapy applicator. We identified five treatment failures in the 70 patients with >6 months' follow-up. Pathologic data, breast imaging, and radiation treatment plans were reviewed. For in-breast failures more than 2 cm away from the original surgical bed, the doses delivered to the areas of recurrence by partial breast irradiation were calculated. Results: At a median follow-up time of 26.1 months, five treatment failures were identified. There were three in-breast failures more than 2 cm away from the original surgical bed, one failure directly adjacent to the original surgical bed, and one failure in the axilla with synchronous distant metastases. The crude failure rate was 7.1% (5 of 70), and the crude local failure rate was 5.7% (4 of 70). Estimated progression-free survival at 48 months was 89.8% (standard error 4.5%). Conclusions: Our case series of 70 patients with >6 months' follow-up and a median follow-up of 26 months is the largest single-institution report to date with detailed failure analysis associated with MammoSite brachytherapy. Our failure data emphasize the importance of patient selection when offering partial breast irradiation.

  18. VizieR Online Data Catalog: Abundance analysis of HD 140283 (Siqueira-Mello+, 2015)

    NASA Astrophysics Data System (ADS)

    Siqueira-Mello, C.; Andrievsky, S. M.; Barbuy, B.; Spite, M.; Spite, F.; Korotin, S. A.

    2015-09-01

    The analysis is carried out using high-resolution (R=81000) and high signal-to-noise ratio (800analysis in NLTE is based on the MULTI code. We present LTE abundances for 26 elements, and NLTE calculations for the species CI, OI, NaI, MgI, AlI, KI, CaI, SrII, and BaII lines. (3 data files).

  19. Accurate abundance analysis of late-type stars: advances in atomic physics

    NASA Astrophysics Data System (ADS)

    Barklem, Paul S.

    2016-05-01

    The measurement of stellar properties such as chemical compositions, masses and ages, through stellar spectra, is a fundamental problem in astrophysics. Progress in the understanding, calculation and measurement of atomic properties and processes relevant to the high-accuracy analysis of F-, G-, and K-type stellar spectra is reviewed, with particular emphasis on abundance analysis. This includes fundamental atomic data such as energy levels, wavelengths, and transition probabilities, as well as processes of photoionisation, collisional broadening and inelastic collisions. A recurring theme throughout the review is the interplay between theoretical atomic physics, laboratory measurements, and astrophysical modelling, all of which contribute to our understanding of atoms and atomic processes, as well as to modelling stellar spectra.

  20. Meta-analysis: abundance, behavior, and hydraulic energy shape biotic effects on sediment transport in streams.

    PubMed

    Albertson, L K; Allen, D C

    2015-05-01

    An increasing number of studies have emphasized the need to bridge the disciplines of ecology and geomorphology. A large number of case studies show that organisms can affect erosion, but a comprehensive understanding of biological impacts on sediment transport conditions is still lacking. We use meta-analysis to synthesize published data to quantify the effects of the abundance, body size, and behavior of organisms on erosion in streams. We also explore the influence of current velocity, discharge, and sediment grain size on the strength of biotic effects on erosion. We found that species that both increase erosion (destabilizers) and decrease erosion (stabilizers) can alter incipient sediment motion, sediment suspension, and sediment deposition above control conditions in which the organisms were not present. When abundance was directly manipulated, these biotic effects were consistently stronger in the higher abundance treatment, increasing effect sizes by 66%. Per capita effect size and per capita biomass were also consistently positively correlated. Fish and crustaceans were the most studied organisms, but aquatic insects increased the effect size by 550 x compared to other types of organisms after accounting for biomass. In streams with lower discharge and smaller grain sizes, we consistently found stronger biotic effects. Taken collectively, these findings provide synthetic evidence that biology can affect physical processes in streams, and these effects can be mediated by hydraulic energy. We suggest that future studies focus on understudied organisms, such as biofilms, conducting experiments under realistic field conditions, and developing hypotheses for the effect of biology on erosion and velocity currents in the context of restoration to better understand the forces that mediate physical disturbances in stream ecosystems. PMID:26236846

  1. A Review of Research and a Meta-Analysis of the Seductive Detail Effect

    ERIC Educational Resources Information Center

    Rey, Gunter Daniel

    2012-01-01

    Seductive details constitute interesting but irrelevant information that are not necessary to achieve the instructional objective. The seductive detail effect occurs when people learn more deeply from instructional messages that exclude rather than include these details. This effect is mainly explained by assuming an overloading of the working…

  2. Detailed Analysis of Solar Data Related to Historical Extreme Geomagnetic Storms: 1868 - 2010

    NASA Astrophysics Data System (ADS)

    Lefèvre, Laure; Vennerstrøm, Susanne; Dumbović, Mateja; Vršnak, Bojan; Sudar, Davor; Arlt, Rainer; Clette, Frédéric; Crosby, Norma

    2016-04-01

    An analysis of historical Sun-Earth connection events in the context of the most extreme space weather events of the last ˜150 years is presented. To identify the key factors leading to these extreme events, a sample of the most important geomagnetic storms was selected based mainly on the well-known aa index and on geomagnetic parameters described in the accompanying paper (Vennerstrøm et al., Solar Phys. in this issue, 2016, hereafter Paper I). This part of the analysis focuses on associating and characterizing the active regions (sunspot groups) that are most likely linked to these major geomagnetic storms. For this purpose, we used detailed sunspot catalogs as well as solar images and drawings from 1868 to 2010. We have systematically collected the most pertinent sunspot parameters back to 1868, gathering and digitizing solar drawings from different sources such as the Greenwich archives, and extracting the missing sunspot parameters. We present a detailed statistical analysis of the active region parameters (sunspots, flares) relative to the geomagnetic parameters developed in Paper I. In accordance with previous studies, but focusing on a much larger statistical sample, we find that the level of the geomagnetic storm is highly correlated to the size of the active regions at the time of the flare and correlated with the size of the flare itself. We also show that the origin at the Sun is most often a complex active region that is also most of the time close to the central meridian when the event is identified at the Sun. Because we are dealing with extremely severe storms, and not the usual severe storm sample, there is also a strong correlation between the size of the linked active region, the estimated transit speed, and the level of the geomagnetic event. In addition, we confirm that the geomagnetic events studied here and the associated events at the Sun present a low probability of occurring at low sunspot number value

  3. CN and CH Abundance Analysis in a Sample of Eight Galactic Globular Clusters

    NASA Astrophysics Data System (ADS)

    Smolinski, Jason P.; Lee, Y.; Beers, T. C.; Martell, S. L.; An, D.; Sivarani, T.

    2011-01-01

    Galactic globular clusters exhibit star-to-star variations in their light element abundances that are not predicted by formation and evolution models involving single stellar generations. Recently it has been suggested that internal pollution from early supernovae and AGB winds may have played important roles in forming a second generation of enriched stars. We present updated results of a CN and CH abundance analysis of stars from the base to the tip of the red giant branch, and in some cases down onto the main sequence, for eight globular clusters with available photometric and spectroscopic data from SDSS-I and SDSS-II/SEGUE. These results include a discussion of the radial distribution of CN enrichment and how this may impact the current paradigm. Funding for SDSS-I and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS Web Site is http://www.sdss.org/. This work was supported in part by grants PHY 02-16783 and PHY 08-22648: Physics Frontiers Center/Joint Institute for Nuclear Astrophysics (JINA), awarded by the U.S. National Science Foundation.

  4. Analysis of Carbohydrate and Fatty Acid Marker Abundance in Ricin Toxin Preparations for Forensic Information

    SciTech Connect

    Colburn, Heather A.; Wunschel, David S.; Kreuzer-Martin, Helen W.; Moran, James J.; Antolick, Kathryn C.; Melville, Angela M.

    2010-07-15

    One challenge in the forensic analysis of ricin samples is determining the method and extent of sample preparation. Ricin purification from the source castor seeds is essentially a protein purification through removal of the non-protein fractions of the seed. Two major, non-protein constituents in the seed are the castor oil and carbohydrates. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil, which comprises roughly half the seed weight. The carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. We used derivatization of carbohydrate and fatty acid markers followed by identification and quantification using gas chromatography/mass spectrometry (GC/MS) to assess compositional changes in ricin samples purified by different methods. The loss of ricinoleic acid indicated steps for oil removal had occurred. Changes to the carbohydrate content of the sample were also observed following protein precipitation. The differential loss of arabinose relative to mannose indicated removal of the major carbohydrate fraction of the seed and enrichment of the protein content. Taken together, these changes in fatty acid and carbohydrate abundance are indicative of the preparation method used for each sample.

  5. Measurement of angle and axis of rotation in a carousel interferometer: a detailed analysis

    SciTech Connect

    Hussain, Ghazanfar; Ikram, Masroor

    2010-02-20

    A detailed analysis of a carousel interferometer is presented for the measurement of an unknown angle and axis of rotation. The technique exploits a set of compensator glass plates and a right-angle prism that is placed in each of the two arms of the interferometer. The two sets are placed at the same rotational stage, while the end mirrors of the interferometer are static. When rotation takes place, individual and relative optical path differences are generated in the two beams of the interferometer. The generated phase differences contribute toward finding the angle and axis of rotation. The analysis is presented for any initial position of the interferometer, i.e., the radial vector from the axis of rotation to the apex of one of the prisms used. The results show the slight variations in the error and nonlinearity when different parameters are manipulated. Moreover, the trade-off between the maximum size of the prisms and the radial distances are also presented.

  6. Detailed product analysis during the low temperature oxidation of n-butane

    PubMed Central

    Herbinet, Olivier; Battin-Leclerc, Frédérique; Bax, Sarah; Le Gall, Hervé; Glaude, Pierre-Alexandre; Fournet, René; Zhou, Zhongyue; Deng, Liulin; Guo, Huijun; Xie, Mingfeng; Qi, Fei

    2013-01-01

    The products obtained from the low-temperature oxidation of n-butane in a jet-stirred reactor (JSR) have been analysed using two methods: gas chromatography analysis of the outlet gas and reflectron time-of-flight mass spectrometry. The mass spectrometer was combined with tunable synchrotron vacuum ultraviolet photoionization and coupled with a JSR via a molecular-beam sampling system. Experiments were performed under quasi-atmospheric pressure, for temperatures between 550 and 800 K, at a mean residence time of 6s and with a stoichiometric n-butane/oxygen/argon mixture (composition = 4/26/70 in mol %). 36 reaction products have been quantified, including addition to the usual oxidation products, acetic acid, hydrogen peroxide, C1, C2 and C4 alkylhydroperoxides and C4 ketohydroperoxides. Evidence of the possible formation of products (dihydrofuranes, furanones) derived from cyclic ethers has also been found. The performance of a detailed kinetic model of the literature has been assessed with the simulation of the formation of this extended range of species. These simulations have also allowed the analysis of possible pathways for the formation of some obtained products. PMID:21031192

  7. Detailed Vibration Analysis of Pinion Gear with Time-Frequency Methods

    NASA Technical Reports Server (NTRS)

    Mosher, Marianne; Pryor, Anna H.; Lewicki, David G.

    2003-01-01

    In this paper, the authors show a detailed analysis of the vibration signal from the destructive testing of a spiral bevel gear and pinion pair containing seeded faults. The vibration signal is analyzed in the time domain, frequency domain and with four time-frequency transforms: the Short Time Frequency Transform (STFT), the Wigner-Ville Distribution with the Choi-Williams kernel (WV-CW), the Continuous Wavelet' Transform (CWT) and the Discrete Wavelet Transform (DWT). Vibration data of bevel gear tooth fatigue cracks, under a variety of operating load levels and damage conditions, are analyzed using these methods. A new metric for automatic anomaly detection is developed and can be produced from any systematic numerical representation of the vibration signals. This new metric reveals indications of gear damage with all of the time-frequency transforms, as well as time and frequency representations, on this data set. Analysis with the CWT detects changes in the signal at low torque levels not found with the other transforms. The WV-CW and CWT use considerably more resources than the STFT and the DWT. More testing of the new metric is needed to determine its value for automatic anomaly detection and to develop fault detection methods for the metric.

  8. Detection and Characterization of Low Abundance Glycopeptides Via Higher-Energy C-Trap Dissociation and Orbitrap Mass Analysis

    NASA Astrophysics Data System (ADS)

    Hart-Smith, Gene; Raftery, Mark J.

    2012-01-01

    Broad-scale mass spectrometric analyses of glycopeptides are constrained by the considerable complexity inherent to glycoproteomics, and techniques are still being actively developed to address the associated analytical difficulties. Here we apply Orbitrap mass analysis and higher-energy C-trap dissociation (HCD) to facilitate detailed insights into the compositions and heterogeneity of complex mixtures of low abundance glycopeptides. By generating diagnostic oxonium product ions at mass measurement errors of <5 ppm, highly selective glycopeptide precursor ion detections are made at sub-fmol limits of detection: analyses of proteolytic digests of a hen egg glycoprotein mixture detect 88 previously uncharacterized glycopeptides from 666 precursor ions selected for MS/MS, with only one false positive due to co-fragmentation of a non-glycosylated peptide with a glycopeptide. We also demonstrate that by (1) identifying multiple series of glycoforms using high mass accuracy single stage MS spectra, and (2) performing product ion scans at optimized HCD collision energies, the identification of peptide + N-acetylhexosamine (HexNAc) ions (Y1 ions) can be readily achieved at <5 ppm mass measurement errors. These data allow base peptide sequences and glycan compositional information to be attained with high confidence, even for glycopeptides that produce weak precursor ion signals and/or low quality MS/MS spectra. The glycopeptides characterized from low fmol abundances using these methods allow two previously unreported glycosylation sites on the Gallus gallus protein ovoglycoprotein (amino acids 82 and 90) to be confirmed; considerable glycan heterogeneities at amino acid 90 of ovoglycoprotein, and amino acids 34 and 77 of Gallus gallus ovomucoid are also revealed.

  9. An Abundance Analysis of R-Coronae Stars in the Galaxy and the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Pollard, K. R.; Cottrell, P. L.; Lawson, W. A.

    1994-05-01

    High-resolution echelle spectra have been obtained of one galactic and two Large Magellanic Cloud (LMC) R Coronae Borealis (RCB) stars with the Anglo-Australian Telescope. An analysis of these data using He- and C- rich models and the WIDTH6 model atmosphere code of Kurucz indicates that the galactic RCB star SU Tau and the two LMC stars, HV 12842 and W Men (HV 966), have similar atmospheric parameters to the warmer galactic RCB and hydrogen-deficient carbon (HdC) stars such as R CrB and XX Cam. The newly analysed RCB stars have T_eff_ ~ 7000 K, log g = 0.5 to 1.0, microturbulent velocities between 7 and 8 km s^-1^ and C/He ratios ranging from 0.0034 to 0.011. An abundance analysis has been performed on these stars for a wide range of species. Special emphasis has been placed on H, He, Li, C, N, O, Fe and the s-process elements. Specific values for [H/He], [Li/Fe] and [Fe/total] (expressed relative to the total abundance of all species) in SU Tau, HV 12842 and W Men are -5,4, -6.2 and -6.5; +2.6, +2.4 and +2.1; and -0.4, -0.7 and -0.7 respectively. The analysis of RCB stars in the LMC provides us with the opportunity to study the metallicity dependence of RCB star evolution.

  10. Direct mutation analysis by high-throughput sequencing: from germline to low-abundant, somatic variants

    PubMed Central

    Gundry, Michael; Vijg, Jan

    2011-01-01

    DNA mutations are the source of genetic variation within populations. The majority of mutations with observable effects are deleterious. In humans mutations in the germ line can cause genetic disease. In somatic cells multiple rounds of mutations and selection lead to cancer. The study of genetic variation has progressed rapidly since the completion of the draft sequence of the human genome. Recent advances in sequencing technology, most importantly the introduction of massively parallel sequencing (MPS), have resulted in more than a hundred-fold reduction in the time and cost required for sequencing nucleic acids. These improvements have greatly expanded the use of sequencing as a practical tool for mutation analysis. While in the past the high cost of sequencing limited mutation analysis to selectable markers or small forward mutation targets assumed to be representative for the genome overall, current platforms allow whole genome sequencing for less than $5,000. This has already given rise to direct estimates of germline mutation rates in multiple organisms including humans by comparing whole genome sequences between parents and offspring. Here we present a brief history of the field of mutation research, with a focus on classical tools for the measurement of mutation rates. We then review MPS, how it is currently applied and the new insight into human and animal mutation frequencies and spectra that has been obtained from whole genome sequencing. While great progress has been made, we note that the single most important limitation of current MPS approaches for mutation analysis is the inability to address low-abundance mutations that turn somatic tissues into mosaics of cells. Such mutations are at the basis of intra-tumor heterogeneity, with important implications for clinical diagnosis, and could also contribute to somatic diseases other than cancer, including aging. Some possible approaches to gain access to low-abundance mutations are discussed, with a

  11. Descriptive statistics tables from a detailed analysis of the National Human Activity Pattern Survey (NHAPS) data

    SciTech Connect

    Tsang, A.M.; Klepeis, N.E.

    1996-07-01

    Detailed results tables are presented from an unweighted statistical analysis of selected portions of the 1992--1994 National Human Activity Pattern Survey (NHAPS) data base. This survey collected data on the potential exposure of Americans to important household pollutants. Randomly selected individuals (9,386) supplied minute-by-minute diaries spanning a 24-hour day as well as follow-up questions on specific exposure types. Selected 24-hour diary locations and activities, selected regroupings of the 24-hour diary locations, activities, and smoker-present categories, and most of the follow-up question variables in the NHAPS data base were statistically analyzed across 12 subgroups (gender, age, Hispanic, education, employment, census region, day-of-week, season, asthma, angina and bronchitis/emphysema). Overall statistics were also generated for the 9,386 total respondents. Tables show descriptive statistics (including frequency distributions) of time spent and frequency of occurrence in each of 39 locations and for 22 activities (that were experienced by more than 50 respondents), along with equivalent tables for 10 regrouped locations (Residence-Indoors, Residence-Outdoors, Inside Vehicle, Near Vehicle, Other Outdoor, Office/Factory, Mall/Store, Public Building, Bar/Restaurant, Other Indoor), seven regrouped activities and smoker present. Tables of frequency distributions of time spent in exposure activities, or the frequency of occurrence of exposure activities, as determined from the follow up questions that were analyzed are also presented. Detailed indices provide page numbers for each table. An Appendix contains a condensed listing of the questionnaires (Versions A and B for adults, child-direct and child-proxy interview types), including the question number, the NHAPS data base variable name, and the verbatim question text.

  12. Detailed spectroscopic analysis of chloride salt deposits in Terra Sirenum, Mars

    NASA Astrophysics Data System (ADS)

    Osterloo, M. M.; Glotch, T. D.; Bandfield, J. L.

    2015-12-01

    Chloride salt-bearing deposits have been identified throughout the southern highlands of Mars [1] based on the lack of diagnostic spectral features of anhydrous chlorides in both the visible near infrared (VNIR) and middle infrared (MIR) wavelength ranges [1,2]. A puzzling aspect of martian chloride deposits is the apparent lack of other weathering or evaporite phases associated with most of the deposits. A global analysis over the chloride salt sites conducted by [3] found that only ~9% of the deposits they analyzed were associated with minerals such as phyllosilicates. Most of these occurrences are in Terra Sirenum where [4] noted that salt-bearing deposits lie stratigraphically above Noachian phyllosilicates. Although a variety of formation mechanisms have been proposed for these intriguing deposits, detailed geologic mapping by [5] suggests that surface water and evaporation played a dominant role. On Earth, evaporative settings are often characterized by a multitude of evaporite and phyllosilicate phases including carbonates, sulfates, and nitrates. [6] evaluated chemical divides and brine evolution for martian systems and their results indicate three pathways wherein late-stage brines favor chloride precipitation. In each case the pathway to chloride formation includes precipitation of carbonates (calcite, siderite, and/or magnesite) and sulfates (gypsum, melanterite, and/or epsomite). Here, we present the results of our detailed and systematic spectroscopic study to identify additional evaporite phases associated with salt/silicate mixtures in Terra Sirenum. [1] Osterloo et al. (2008) Science, 319, [2] Glotch, T. D. et al. (2013) Lunar and Planet. Sci. XLIV, abstract #1549 [3] Ruesch, O. et al. (2012), J. Geophys. Res., 117, E00J13 [4] Glotch, T. D. et al. (2010) Geophys. Res. Lett. 37, L16202, [5] Osterloo, M. M. and B. M Hynek (2015) Lunar and Planet. Sci XLVI. Abstract #1054 [6] Tosca, N. J. and S. M. McLennan (2006), Earth and Planet. Sci. Lett., 241.

  13. ANALYSIS OF RICIN TOXIN PREPARATIONS FOR CARBOHYDRATE AND FATTY ACID ABUNDANCE AND ISOTOPE RATIO INFORMATION

    SciTech Connect

    Wunschel, David S.; Kreuzer-Martin, Helen W.; Antolick, Kathryn C.; Colburn, Heather A.; Moran, James J.; Melville, Angela M.

    2009-12-01

    This report describes method development and preliminary evaluation for analyzing castor samples for signatures of purifying ricin. Ricin purification from the source castor seeds is essentially a problem of protein purification using common biochemical methods. Indications of protein purification will likely manifest themselves as removal of the non-protein fractions of the seed. Two major, non-protein, types of biochemical constituents in the seed are the castor oil and various carbohydrates. The oil comprises roughly half the seed weight while the carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. Different castor oil and carbohydrate components can serve as indicators of specific toxin processing steps. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil. The loss of ricinoleic acid indicates a step to remove oil from the seeds. The relative amounts of carbohydrates and carbohydrate-like compounds, including arabinose, xylose, myo-inositol fucose, rhamnose, glucosamine and mannose detected in the sample can also indicate specific processing steps. For instance, the differential loss of arabinose relative to mannose and N-acetyl glucosamine indicates enrichment for the protein fraction of the seed using protein precipitation. The methods developed in this project center on fatty acid and carbohydrate extraction from castor samples followed by derivatization to permit analysis by gas chromatography-mass spectrometry (GC-MS). Method descriptions herein include: the source and preparation of castor materials used for method evaluation, the equipment and description of procedure required for chemical derivatization, and the instrument parameters used in the analysis. Two types of derivatization methods describe analysis of carbohydrates and one procedure for analysis of fatty acids. Two types of GC-MS analysis is included in the method development, one

  14. A global/local analysis method for treating details in structural design

    NASA Technical Reports Server (NTRS)

    Aminpour, Mohammad A.; Mccleary, Susan L.; Ransom, Jonathan B.

    1993-01-01

    A method for analyzing global/local behavior of plate and shell structures is described. In this approach, a detailed finite element model of the local region is incorporated within a coarser global finite element model. The local model need not be nodally compatible (i.e., need not have a one-to-one nodal correspondence) with the global model at their common boundary; therefore, the two models may be constructed independently. The nodal incompatibility of the models is accounted for by introducing appropriate constraint conditions into the potential energy in a hybrid variational formulation. The primary advantage of this method is that the need for transition modeling between global and local models is eliminated. Eliminating transition modeling has two benefits. First, modeling efforts are reduced since tedious and complex transitioning need not be performed. Second, errors due to the mesh distortion, often unavoidable in mesh transitioning, are minimized by avoiding distorted elements beyond what is needed to represent the geometry of the component. The method is applied reduced to a plate loaded in tension and transverse bending. The plate has a central hole, and various hole sixes and shapes are studied. The method is also applied to a composite laminated fuselage panel with a crack emanating from a window in the panel. While this method is applied herein to global/local problems, it is also applicable to the coupled analysis of independently modeled components as well as adaptive refinement.

  15. IP Network Failure Identification Based on the Detailed Analysis of OSPF LSA Flooding

    NASA Astrophysics Data System (ADS)

    Hei, Yuichiro; Ogishi, Tomohiko; Ano, Shigehiro; Hasegawa, Toru

    It is important to monitor routing protocols to ensure IP networks and their operations can maintain sufficient level of stability and reliability because IP routing is an essential part of such networks. In this paper, we focus on Open Shortest Path First (OSPF), a widely deployed intra-domain routing protocol. Routers running OSPF advertise their link states on Link State Advertisements (LSAs) as soon as they detect changes in their link states. In IP network operations, it is important for operators to ascertain the location and type of a failure in order to deal with failures adequately. We therefore studied IP network failure identification based on the monitoring of OSPF LSAs. There are three issues to consider in regard to identifying network failures by monitoring LSAs. The first is that multiple LSAs are flooded by a single failure. The second is the LSA delay, and the third is that multiple failures may occur simultaneously. In this paper, we propose a method of network failure identification based on a detailed analysis of OSPF LSA flooding that takes into account the above three issues.

  16. A DETAILED MODEL ATMOSPHERE ANALYSIS OF COOL WHITE DWARFS IN THE SLOAN DIGITAL SKY SURVEY

    SciTech Connect

    Kilic, Mukremin; Leggett, S. K.; Tremblay, P.-E.; Bergeron, P.; Von Hippel, Ted; Harris, Hugh C.; Munn, Jeffrey A.; Williams, Kurtis A.; Gates, Evalyn; Farihi, J.

    2010-09-15

    We present optical spectroscopy and near-infrared photometry of 126 cool white dwarfs (WDs) in the Sloan Digital Sky Survey (SDSS). Our sample includes high proper motion targets selected using the SDSS and USNO-B astrometry and a dozen previously known ultracool WD candidates. Our optical spectroscopic observations demonstrate that a clean selection of large samples of cool WDs in the SDSS (and the SkyMapper, Pan-STARRS, and the Large Synoptic Survey Telescope data sets) is possible using a reduced proper motion diagram and a tangential velocity cut-off (depending on the proper motion accuracy) of 30 km s{sup -1}. Our near-infrared observations reveal eight new stars with significant absorption. We use the optical and near-infrared photometry to perform a detailed model atmosphere analysis. More than 80% of the stars in our sample are consistent with either pure hydrogen or pure helium atmospheres. However, the eight stars with significant infrared absorption and the majority of the previously known ultracool WD candidates are best explained with mixed hydrogen and helium atmosphere models. The age distribution of our sample is consistent with a Galactic disk age of 8 Gyr. A few ultracool WDs may be as old as 12-13 Gyr, but our models have problems matching the spectral energy distributions of these objects. There are only two halo WD candidates in our sample. However, trigonometric parallax observations are required for accurate mass and age determinations and to confirm their membership in the halo.

  17. External assistance to the health sector in developing countries: a detailed analysis, 1972-90.

    PubMed Central

    Michaud, C.; Murray, C. J.

    1994-01-01

    This study, which was conducted for the World Bank's World development report 1993: investing in health, provides an objective analysis of the external assistance to the health sector by quantifying in detail the sources and recipients of such assistance in 1990, by analysing time trends for external assistance to the health sector over the last two decades, and, to the extent possible, by describing the allocation of resources to specific activities in the health sector. The main findings of the study are that total external assistance to the health sector in 1990 was US$ 4800 million, or only 2.9% of total health expenditures in developing countries. After stagnation in real terms during the first half of the 1980s, health sector assistance has been increasing since 1986. Despite their small volume, external assistance at the margins may play a critical role in capital investment, research and strategic planning. The study confirms prior findings that health status variables per se are not related to the amount of aid received. Comparing investments to the burden of disease shows tremendous differences in the funding for different health problems. A number of conditions are comparatively under-financed, particularly noncommunicable diseases and injuries. PMID:7923543

  18. Detailed analysis of the first MOAO results obtained by CANARY at the WHT.

    NASA Astrophysics Data System (ADS)

    Vidal, F.; Gendron, E.; Brangier, M.; Morris, T.; Basden, A.; Myers, R.; Rousset, G.; Hubert, Z.; Chemla, F.; Longmore, A.; Butterley, T.; Dipper, N.; Dunlop, C.; Geng, D.; Gratadour, D.; Henry, D.; Laporte, P.; Looker, N.; Perret, D.; Sevin, A.; Talbot, G.; Younger, E.

    2011-09-01

    CANARY is the multi-object adaptive optics (MOAO) pathfinder for the multi object IR spectrometer EAGLE currently proposed on the European Extremely Large Telescope (E-ELT). CANARY was installed in September 2010 on the William Herschel Telescope (WHT) Canary Islands, Spain. For the first time, MOAO correction has been demonstrated using 3 widely separated off-axis natural guide stars and one deformable mirror in open loop in a target direction. A fourth on-axis wavefront sensor (WFS), called truth sensor (TS) was used to characterise the residual error of the MOAO correction. As the TS is placed after the deformable mirror it also permits CANARY to operate as a classical on-axis closed-loop AO system for performance comparison purposes. We present the detailed analysis of the fourth night of the September observation run (2010 Sep. 27th). Strehls ratios of 0.20 in H band were measured in MOAO mode while achieving 0.25 in close loop configuration (r0 = 15 cm at 0.5 microns). We also acquired synchronised slopes from the 3 off-axis WFS and the TS and from these data we derive the full error budget of CANARY. We pay particular attention to the performance of the tomographic reconstruction and the open loop error. We also discuss the turbulence profile retrieved during the night that was directly measured from the instrument data in order to compute an optimized tomographic reconstruction of the on-axis wavefront.

  19. Designing the optimal semi-warm NIR spectrograph for SALT via detailed thermal analysis

    NASA Astrophysics Data System (ADS)

    Wolf, Marsha J.; Sheinis, Andrew I.; Mulligan, Mark P.; Wong, Jeffrey P.; Rogers, Allen

    2008-07-01

    The near infrared (NIR) upgrade to the Robert Stobie Spectrograph (RSS) on the Southern African Large Telescope (SALT), RSS/NIR, extends the spectral coverage of all modes of the optical spectrograph. The RSS/NIR is a low to medium resolution spectrograph with broadband, spectropolarimetric, and Fabry-Perot imaging capabilities. The optical and NIR arms can be used simultaneously to extend spectral coverage from 3200 Å to approximately 1.6 μm. Both arms utilize high efficiency volume phase holographic gratings via articulating gratings and cameras. The NIR camera incorporates a HAWAII-2RG detector with an Epps optical design consisting of 6 spherical elements and providing subpixel rms image sizes of 7.5 +/- 1.0 μm over all wavelengths and field angles. The NIR spectrograph is semi-warm, sharing a common slit plane and partial collimator with the optical arm. A pre-dewar, cooled to below ambient temperature, houses the final NIR collimator optic, the grating/Fabry-Perot etalon, the polarizing beam splitter, and the first three camera optics. The last three camera elements, blocking filters, and detector are housed in a cryogenically cooled dewar. The semi-warm design concept has long been proposed as an economical way to extend optical instruments into the NIR, however, success has been very limited. A major portion of our design effort entails a detailed thermal analysis using non-sequential ray tracing to interactively guide the mechanical design and determine a truly realizable long wavelength cutoff over which astronomical observations will be sky-limited. In this paper we describe our thermal analysis, design concepts for the staged cooling scheme, and results to be incorporated into the overall mechanical design and baffling.

  20. Detailed Analysis of Starburst and AGN Activity in Blue E/S0 Galaxies in RESOLVE

    NASA Astrophysics Data System (ADS)

    Bittner, Ashley; Snyder, Elaine M.; Kannappan, Sheila; Norman, Dara J.; Norris, Mark A.; Moffett, Amanda J.; Hoversten, Erik A.; Stark, David; RESOLVE Team

    2016-01-01

    We identify a population of ~120 blue E/S0 galaxies among the ~1350 galaxies that are targeted for spectroscopy and have measured morphologies in the highly complete REsolved Spectroscopy Of a Local Volume (RESOLVE) survey. Blue E/S0s are identified as being early type objects morphologically classified between E and S0/a that fall on the blue sequence. Most (~85%) of our blue E/S0s have stellar masses <10^10 M_sun. Using pPXF, we have measured the stellar velocity dispersions (sigma values) from high resolution 485 - 550 nm spectroscopy for ~15% of the blue E/S0 sample. Using three variations of the M_BH -- sigma relation, this kinematic subsample is estimated to typically host central black holes within the range log M_BH = 4-6 M_sun. Following up on previous suggestions of nuclear activity in the blue E/S0 population, we investigate nuclear starburst and/or AGN activity occurring within the full sample. Preliminary results from cross-checking known AGN catalogs with the blue E/S0 sample have revealed nuclear activity in ~20 of these galaxies based on heterogeneous criteria (BPT line ratio analysis, spectral line broadening, etc.), some of which may not entirely distinguish starburst from AGN activity. In an attempt to break the degeneracy between AGN and starburst activity, we perform detailed spectral analysis for a few of the galaxies with kinematic data. We also consider the viability of alternate AGN detection methods based on L_Edd estimates calculated from the M_BH estimates. This research has been supported by the National Science Foundation through the CAP REU Program (ACI-1156614) and the RESOLVE Survey (AST-0955368) as well as the National Space Grant College and Fellowship Program and the NC Space Grant Consortium.

  1. High-resolution abundance analysis of two stars near the globular cluster NGC 6522 projected in Baade's Window.

    NASA Astrophysics Data System (ADS)

    Castro, S.; Barbuy, B.; Bica, E.; Ortolani, S.; Renzini, A.

    1995-05-01

    The CASPEC ,echelle spectrograph at the ESO 3.6 m telescope was used to obtain high resolution spectra of Arp 1145 and Arp 2240, two stars of the Baade Window, near the globular cluster NGC 6522. The stars were selected from the list of Pickles & van der Kruit (1990), as one being metal-poor and the other one metal-rich. From a detailed analysis using equivalent widths and spectrum synthesis we derive the stellar parameters (T_eff_, log g and [M/H])=(4750,1.2,-0.9) and (5000,2.15,+0.2), respectively for Arp 1145 and Arp 2240. For the metal-poor star Arp 1145, excesses of oxygen, calcium and titanium relative to iron are found; it may be a member of NGC 6522 or a halo star now traversing the bulge. Arp 2240, showing nearly solar metallicity and solar abundance ratios seems to belong to the inner disk population. The metallicity for the metal-rich star Arp 2240 indicates that previous work based on mid-resolution spectra tended to overestimate metallicities of metal-rich stars by =~0.2-0.3dex, in agreement with the recent results by McWilliam & Rich (1994).

  2. Detailed analysis of an Eigen quasispecies model in a periodically moving sharp-peak landscape

    NASA Astrophysics Data System (ADS)

    Neves, Armando G. M.

    2010-09-01

    The Eigen quasispecies model in a periodically moving sharp-peak landscape considered in previous seminal works [M. Nilsson and N. Snoad, Phys. Rev. Lett. 84, 191 (2000)10.1103/PhysRevLett.84.191] and [C. Ronnewinkel , in Theoretical Aspects of Evolutionary Computing, edited by L. Kallel, B. Naudts, and A. Rogers (Springer-Verlag, Heidelberg, 2001)] is analyzed in greater detail. We show here, through a more rigorous analysis, that results in those papers are qualitatively correct. In particular, we obtain a phase diagram for the existence of a quasispecies with the same shape as in the above cited paper by C. Ronnewinkel , with upper and lower thresholds for the mutation rate between which a quasispecies may survive. A difference is that the upper value is larger and the lower value is smaller than the previously reported ones, so that the range for quasispecies existence is always larger than thought before. The quantitative information provided might also be important in understanding genetic variability in virus populations and has possible applications in antiviral therapies. The results in the quoted papers were obtained by studying the populations only at some few genomes. As we will show, this amounts to diagonalizing a 3×3 matrix. Our work is based instead in a different division of the population allowing a finer control of the populations at various relevant genetic sequences. The existence of a quasispecies will be related to Perron-Frobenius eigenvalues. Although huge matrices of sizes 2ℓ , where ℓ is the genome length, may seem necessary at a first look, we show that such large sizes are not necessary and easily obtain numerical and analytical results for their eigenvalues.

  3. Propagating Disturbances in Coronal Loops: A Detailed Analysis of Propagation Speeds

    NASA Astrophysics Data System (ADS)

    Kiddie, G.; De Moortel, I.; Del Zanna, G.; McIntosh, S. W.; Whittaker, I.

    2012-08-01

    Quasi-periodic disturbances have been observed in the outer solar atmosphere for many years. Although first interpreted as upflows (Schrijver et al., Solar Phys. 187, 261, 1999), they have been widely regarded as slow magneto-acoustic waves, due to their observed velocities and periods. However, recent observations have questioned this interpretation, as periodic disturbances in Doppler velocity, line width, and profile asymmetry were found to be in phase with the intensity oscillations (De Pontieu and McIntosh, Astrophys. J. 722, 1013, 2010; Tian, McIntosh, and De Pontieu, Astrophys. J. Lett. 727, L37, 2011), suggesting that the disturbances could be quasi-periodic upflows. Here we conduct a detailed analysis of the velocities of these disturbances across several wavelengths using the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). We analysed 41 examples, including both sunspot and non-sunspot regions of the Sun. We found that the velocities of propagating disturbances (PDs) located at sunspots are more likely to be temperature dependent, whereas the velocities of PDs at non-sunspot locations do not show a clear temperature dependence. This suggests an interpretation in terms of slow magneto-acoustic waves in sunspots but the nature of PDs in non-sunspot (plage) regions remains unclear. We also considered on what scale the underlying driver is affecting the properties of the PDs. Finally, we found that removing the contribution due to the cooler ions in the 193 Å wavelength suggests that a substantial part of the 193 Å emission of sunspot PDs can be attributed to the cool component of 193 Å.

  4. Investigating microbial carbon cycling using natural abundance isotope analysis of PLFA

    NASA Astrophysics Data System (ADS)

    Slater, G. G.; Brady, A.; Cowie, B.

    2008-12-01

    Understanding microbial carbon sources and cycling is fundamental to our conceptualization of microbial ecosystems and their role in biogeochemical cycling in natural systems. Achieving this understanding requires application of a wide range of approaches. Natural abundance isotope analysis of individual compounds, particularly cellular components such as Phospholipids Fatty Acids (PLFA) can provide insights into the carbon sources and metabolic activities of the in situ microbial community from environmental samples. This is primarily because specific PLFA can be well resolved by gas chromatography even from complex matrices where confounding biological/organic compound abound. These PLFA can then be attributed to the viable microbial community, in some cases to specific components of this community and due to characteristic biosynthetic fractionations of stable isotope ratios, δ13C analysis of PLFA can: differentiate isotopically distinct primary carbon sources of heterotrophic communities; identify isotopic patterns characteristic of autotrophic versus heterotrophic processes; and elucidate microbial biosynthetic pathways. In cases where there δ13C cannot provide resolution of carbon sources, new approaches in Δ14C of PLFA can be applied. The vast range in Δ14C of ancient and modern carbon provides an easily traceable signal that can differentiate uptake and utilization of these carbon sources. This is particularly useful in cases such as contaminated sites where petroleum based contamination has occurred, or in natural systems where microbial communities may be utilizing geologic versus recently photosynthetically fixed carbon. This talk will present several examples demonstrating the utility of this approach.

  5. Comprehensive Analysis of Stop Codon Usage in Bacteria and Its Correlation with Release Factor Abundance*

    PubMed Central

    Korkmaz, Gürkan; Holm, Mikael; Wiens, Tobias; Sanyal, Suparna

    2014-01-01

    We present a comprehensive analysis of stop codon usage in bacteria by analyzing over eight million coding sequences of 4684 bacterial sequences. Using a newly developed program called “stop codon counter,” the frequencies of the three classical stop codons TAA, TAG, and TGA were analyzed, and a publicly available stop codon database was built. Our analysis shows that with increasing genomic GC content the frequency of the TAA codon decreases and that of the TGA codon increases in a reciprocal manner. Interestingly, the release factor 1-specific codon TAG maintains a more or less uniform frequency (∼20%) irrespective of the GC content. The low abundance of TAG is also valid with respect to expression level of the genes ending with different stop codons. In contrast, the highly expressed genes predominantly end with TAA, ensuring termination with either of the two release factors. Using three model bacteria with different stop codon usage (Escherichia coli, Mycobacterium smegmatis, and Bacillus subtilis), we show that the frequency of TAG and TGA codons correlates well with the relative steady state amount of mRNA and protein for release factors RF1 and RF2 during exponential growth. Furthermore, using available microarray data for gene expression, we show that in both fast growing and contrasting biofilm formation conditions, the relative level of RF1 is nicely correlated with the expression level of the genes ending with TAG. PMID:25217634

  6. Landscape evolution reconstructions on Mars: a detailed analysis of lacustrine and fluvial terraces

    NASA Astrophysics Data System (ADS)

    Rossato, Sandro; Pajola, Maurizio; Baratti, Emanuele; Mangili, Clara; Coradini, Marcello

    2015-04-01

    Liquid water was flowing on the surface of Mars in the past, leaving behind a wide range of geomorphic features. The ancient major Martian water fluxes vanished about 3.5 Ga. Meteoritic impacts, wind-erosion, gravity-related phenomena, tectonic deformations and volcanic activities deeply altered the landforms during the ages. Hence, the reconstruction of water-shaped landscapes is often complicated. Fluvial and lacustrine terraces analysis and correlation is a useful approach to understand and reconstruct the past changes in Martian landscape evolution. These features are commonly used as reference for the top of water bodies on Earth, since they are void of the uncertainties or errors deriving from erosional or slumping processes that could have acted on the valley flanks or in the plateau, where the hydrological network was carved in. The study area is located in the western hemisphere of Mars, in the Memnonia quadrangle, between latitude 9° 10'-9° 50'South and longitude 167° 0'-167° 30' West and it constitutes a transition region between the southern highlands of Terra Sirenum and the northern lowlands of Lucus Planum. Many water-shaped features have already been described near the study area, the most prominent of them being the Ma'adim Vallis and the Mangala Valles system. Our results derive from the observations and the analysis of HRSC images (12.5 m spatial resolution) and Digital Elevation Models (DEMs) derived from the MEX-HRSC (75 m resolution), that allow the identification of elevation differences up to the tens of meter scale. We were able to reconstruct six main evolutionary stages of a complex hydrologic systems consisting of two main palaeorivers (up to 5 km wide) connected one another by a palaeolake that formed within a meteor crater (~20 km diameter). On the basis of Earth analogs, these stages/terraces should have evolved during a long period of time, at least thousands years long. Furthermore, crater counting date back the deactivation of

  7. DETAILED COMPOSITIONAL ANALYSIS OF THE HEAVILY POLLUTED DBZ WHITE DWARF SDSS J073842.56+183509.06: A WINDOW ON PLANET FORMATION?

    SciTech Connect

    Dufour, P.; Fontaine, G.; Bergeron, P.; Kilic, M.; Melis, C.; Bochanski, J.

    2012-04-10

    We present a new model atmosphere analysis of the most metal-contaminated white dwarf known, the DBZ SDSS J073842.56+183509.06. Using new high-resolution spectroscopic observations taken with Keck and Magellan, we determine precise atmospheric parameters and measure abundances of 14 elements heavier than helium. We also report new Spitzer mid-infrared photometric data that are used to better constrain the properties of the debris disk orbiting this star. Our detailed analysis, which combines data taken from seven different observational facilities (Galaxy Evolution Explorer, Gemini, Keck, Magellan, MMT, Sloan Digital Sky Survey, and Spitzer), clearly demonstrates that J0738+1835 is accreting large amounts of rocky terrestrial-like material that has been tidally disrupted into a debris disk. We estimate that the body responsible for the photospheric metal contamination was at least as large as Ceres, but was much drier, with less than 1% of the mass contained in the form of water ice, indicating that it formed interior to the snow line around its parent star. We also find a correlation between the abundances (relative to Mg and bulk Earth) and the condensation temperature; refractory species are clearly depleted, while the more volatile elements are possibly enhanced. This could be the signature of a body that formed in a lower temperature environment than where Earth formed. Alternatively, we could be witnessing the remains of a differentiated body that lost a large part of its outer layers.

  8. An efficient extraction method to enhance analysis of low abundant proteins from soybean seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large amounts of the major seed storage proteins, such as ß-conglycinin and glycinin, in soybean (Glycine max) seeds hinder the isolation and characterization of less abundant seed proteins. We investigated whether isopropanol extraction could facilitate resolution of the less abundant proteins fro...

  9. VARIATION IN JUVENILE COHO SALMON SUMMER ABUNDANCE: HIERARCHICAL ANALYSIS OF HABITAT EFFECTS

    EPA Science Inventory

    Varying habitat conditions found across a stream network during the summer months may limit the abundance of salmonids such as coho (Oncorhynchus kisutch). We examined the abundance of juvenile coho salmon across a stream network in an Oregon coast range basin from 2002 through ...

  10. A Detailed Immunohistochemical Analysis of a Large Series of Cervical and Vaginal Gastric-type Adenocarcinomas.

    PubMed

    Carleton, Claire; Hoang, Lien; Sah, Shatrughan; Kiyokawa, Takako; Karamurzin, Yevgeniy S; Talia, Karen L; Park, Kay J; McCluggage, W Glenn

    2016-05-01

    Adenocarcinomas exhibiting gastric differentiation represent a recently described and uncommon subtype of non-human papillomavirus (HPV)-related cervical adenocarcinoma. They comprise a spectrum from a well-differentiated variant (adenoma malignum/mucinous variant of minimal deviation adenocarcinoma) to a more poorly differentiated overtly malignant form, generally referred to as gastric-type adenocarcinoma. Rarely, such tumors have also been described as primary vaginal neoplasms. Gastric-type adenocarcinomas exhibit considerable morphologic overlap with adenocarcinomas originating outside the female genital tract, especially mucinous adenocarcinomas arising in the pancreas and biliary tract. Moreover, they often metastasize to unusual sites, such as the ovary and peritoneum/omentum, where they can be mistaken for metastatic adenocarcinomas from other, nongynecologic sites. There is little information regarding the immunophenotype of gastric-type adenocarcinomas, and knowledge of this is important to aid in the distinction from other adenocarcinomas. In this study, we undertook a detailed immunohistochemical analysis of a large series of cervical (n=45) and vaginal (n=2) gastric-type adenocarcinomas. Markers included were cytokeratin (CK)7, CK20, CDX2, carcinoembryonic antigen, CA125, CA19.9, p16, estrogen receptor, progesterone receptor, MUC6, PAX8, PAX2, p53, hepatocyte nuclear factor 1 beta, carbonic anhydrase IX, human epidermal receptor 2 (HER2), and mismatch repair (MMR) proteins. All markers were classified as negative, focal (<50% of tumor cells positive), or diffuse (≥50% tumor cells positive) except for p53 (classified as "wild-type" or "mutation-type"), HER2 (scored using the College of American Pathologists guidelines for gastric carcinomas), and MMR proteins (categorized as retained or lost). There was positive staining with CK7 (47/47-45 diffuse, 2 focal), MUC6 (17/21-6 diffuse, 11 focal), carcinoembryonic antigen (25/31-12 diffuse, 13 focal

  11. Chemical abundances and kinematics of 257 G-, K-type field giants. Setting a base for further analysis of giant-planet properties orbiting evolved stars

    NASA Astrophysics Data System (ADS)

    Adibekyan, V. Zh.; Benamati, L.; Santos, N. C.; Alves, S.; Lovis, C.; Udry, S.; Israelian, G.; Sousa, S. G.; Tsantaki, M.; Mortier, A.; Sozzetti, A.; De Medeiros, J. R.

    2015-06-01

    We performed a uniform and detailed abundance analysis of 12 refractory elements (Na, Mg, Al, Si, Ca, Ti, Cr, Ni, Co, Sc, Mn, and V) for a sample of 257 G- and K-type evolved stars from the CORALIE planet search programme. To date, only one of these stars is known to harbour a planetary companion. We aimed to characterize this large sample of evolved stars in terms of chemical abundances and kinematics, thus setting a solid base for further analysis of planetary properties around giant stars. This sample, being homogeneously analysed, can be used as a comparison sample for other planet-related studies, as well as for different type of studies related to stellar and Galaxy astrophysics. The abundances of the chemical elements were determined using an local thermodynamic equilibrium (LTE) abundance analysis relative to the Sun, with the spectral synthesis code MOOG and a grid of Kurucz ATLAS9 atmospheres. To separate the Galactic stellar populations, both a purely kinematical approach and a chemical method were applied. We confirm the overabundance of Na in giant stars compared to the field FGK dwarfs. This enhancement might have a stellar evolutionary character, but departures from LTE may also produce a similar enhancement. Our chemical separation of stellar populations also suggests a `gap' in metallicity between the thick-disc and high-α metal-rich stars, as previously observed in dwarfs sample from HARPS. The present sample, as most of the giant star samples, also suffers from the B - V colour cut-off, which excludes low-log g stars with high metallicities, and high-log g star with low [Fe/H]. For future studies of planet occurrence dependence on stellar metallicity around these evolved stars, we suggest to use a subsample of stars in a `cut-rectangle' in the log g-[Fe/H] diagram to overcome the aforementioned issue.

  12. Chemical method for nitrogen isotopic analysis of ammonium at natural abundance.

    PubMed

    Liu, Dongwei; Fang, Yunting; Tu, Ying; Pan, Yuepeng

    2014-04-15

    We report a new chemical method to determine the (15)N natural abundance (δ(15)N) for ammonium (NH4(+)) in freshwater (e.g., precipitation) and soil KCl extract. This method is based on the isotopic analysis of nitrous oxide (N2O). Ammonium is initially oxidized to nitrite (NO2(-)) by hypobromite (BrO(-)) using previously established procedures. NO2(-) is then quantitatively converted into N2O by hydroxylamine (NH2OH) under strongly acid conditions. The produced N2O is analyzed by a commercially available purge and cryogenic trap system coupled to an isotope ratio mass spectrometer (PT-IRMS). On the basis of a typical analysis size of 4 mL, the standard deviation of δ(15)N measurements is less than 0.3‰ and often better than 0.1‰ (3 to 5 replicates). Compared to previous methods, the technique here has several advantages and the potential to be used as a routine method for (15)N/(14)N analysis of NH4(+): (1) substantially simplified preparation procedures and reduced preparation time particularly compared to the methods in which diffusion or distillation is involved since all reactions occur in the same vial and separation of NH4(+) from solution is not required; (2) more suitability for low volume samples including those with low N concentration, having a blank size of 0.6 to 2 nmol; (3) elimination of the use of extremely toxic reagents (e.g., HN3) and/or the use of specialized denitrifying bacterial cultures which may be impractical for many laboratories. PMID:24654992

  13. New mapping of Radlandi basin and detailed analysis of its inner plains

    NASA Astrophysics Data System (ADS)

    Minelli, Francesco; Giorgetti, Carolina; Mondini, Alessandro; Pauselli, Cristina; Mancinelli, Paolo

    2013-04-01

    NEW MAPPING OF RADITLADI BASIN AND DETAILED ANALYSIS OF ITS INNER PLAINS. Francesco Minelli 1, Carolina Giorgetti 1, Alessandro C. Mondini 2, Cristina Pauselli 1, Paolo Mancinelli1. 1 Gruppo di Geologia Strutturale e Geofisica (GSG), Dipartimento di Scienze della Terra, Università degli Studi di Perugia, 06123, Perugia, Italy . Email: minelli91@yahoo.it. 2 CNR IRPI Perugia, 06123, Perugia. Introduction: The Raditladi basin is a large peak-ring impact crater discovered during the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) first flyby of Mercury in January 2008 [1]. The Raditladi basin is relatively young [2], and the study of the internal structures give an indication of the processes that acted recently in Mercury's geological history. Geological mapping: We first present the geological mapping of Raditladi crater. In the map we defined different sub-units on the base of previous studies [4][5] and surface morphology and reflectance. Through a GIS software we associated a polygonal layer to each sub-unit, this allowed to distinguish nine different layers. Due to the similarities with the Rachmaninoff basin, to define sub-units mapped on Raditladi, we adopted Rachmaninoff crater's units definitions made by Marchi et al. (2011) [4]. Structures analysis : We also mapped secondary structures consisting in concentric troughs arranged in a circular pattern. We defined two different kinds of troughs: (i) structures characterized by a distinct flat floor and interpretable as grabens, and (ii) structures with linear and curvilinear segments [5]. Inner plain deposit: The analysis of the topography made possible the estimation of the deposit's thickness. The measurement of the thickness is possible thanks to the presence of two small craters, crater A and crater, located in Raditladi's Inner plain. Observing the morphology of the two small craters' rim and hummocky central floor, we distinguished two different units: the shallower consists in

  14. VizieR Online Data Catalog: HE 2252-4225 abundance analysis (Mashonkina+, 2014)

    NASA Astrophysics Data System (ADS)

    Mashonkina, L.; Christlieb, N.; Eriksson, K.

    2014-07-01

    HE 2252-4225 was identified as a candidate metal-poor star in the Hamburg/ESO Survey (HES), and it was included in the target list of the Hamburg/ESO R-process-Enhanced Star survey (HERES, Christlieb et al., Paper I, 2004A&A...428.1027C). Stellar parameters, Teff=4708+-100K, logg=1.53+/-0.24, and [Fe/H]=-2.83+/-0.12, were first determined by Barklem et al. (Paper II. Cat. J/A+A/439/129) based on automated abundance analysis of high-resolution "snapshot" spectra. The photometry was taken from Beers et al. (2007, Cat. J/ApJS/168/128). High-quality spectra of this star was acquired during May-September 2005 with the VLT and UVES in dichroic mode. The BLUE390+RED580 (9h total integration time) and BLUE437+RED860 (10h) standard settings were employed to ensure a wide wavelength coverage. (2 data files).

  15. Bayesian change point analysis of abundance trends for pelagic fishes in the upper San Francisco Estuary

    USGS Publications Warehouse

    Thompson, James R.; Kimmerer, Wim J.; Brown, Larry R.; Newman, Ken B.; Mac Nally, Ralph; Bennett, William A.; Feyrer, Frederick; Fleishman, Erica

    2010-01-01

    We examined trends in abundance of four pelagic fish species (delta smelt, longfin smelt, striped bass, and threadfin shad) in the upper San Francisco Estuary, California, USA, over 40 years using Bayesian change point models. Change point models identify times of abrupt or unusual changes in absolute abundance (step changes) or in rates of change in abundance (trend changes). We coupled Bayesian model selection with linear regression splines to identify biotic or abiotic covariates with the strongest associations with abundances of each species. We then refitted change point models conditional on the selected covariates to explore whether those covariates could explain statistical trends or change points in species abundances. We also fitted a multispecies change point model that identified change points common to all species. All models included hierarchical structures to model data uncertainties, including observation errors and missing covariate values. There were step declines in abundances of all four species in the early 2000s, with a likely common decline in 2002. Abiotic variables, including water clarity, position of the 2‰ isohaline (X2), and the volume of freshwater exported from the estuary, explained some variation in species' abundances over the time series, but no selected covariates could explain statistically the post-2000 change points for any species.

  16. Eigenvalue analysis of an irreversible random walk with skew detailed balance conditions.

    PubMed

    Sakai, Yuji; Hukushima, Koji

    2016-04-01

    An irreversible Markov-chain Monte Carlo (MCMC) algorithm with skew detailed balance conditions originally proposed by Turitsyn et al. is extended to general discrete systems on the basis of the Metropolis-Hastings scheme. To evaluate the efficiency of our proposed method, the relaxation dynamics of the slowest mode and the asymptotic variance are studied analytically in a random walk on one dimension. It is found that the performance in irreversible MCMC methods violating the detailed balance condition is improved by appropriately choosing parameters in the algorithm. PMID:27176439

  17. Eigenvalue analysis of an irreversible random walk with skew detailed balance conditions

    NASA Astrophysics Data System (ADS)

    Sakai, Yuji; Hukushima, Koji

    2016-04-01

    An irreversible Markov-chain Monte Carlo (MCMC) algorithm with skew detailed balance conditions originally proposed by Turitsyn et al. is extended to general discrete systems on the basis of the Metropolis-Hastings scheme. To evaluate the efficiency of our proposed method, the relaxation dynamics of the slowest mode and the asymptotic variance are studied analytically in a random walk on one dimension. It is found that the performance in irreversible MCMC methods violating the detailed balance condition is improved by appropriately choosing parameters in the algorithm.

  18. Secondary ion mass spectrometry combined with alpha track detection for isotope abundance ratio analysis of individual uranium-bearing particles.

    PubMed

    Esaka, Fumitaka; Magara, Masaaki

    2014-03-01

    Secondary ion mass spectrometry (SIMS) was used in combination with alpha track detection for the efficient analysis of uranium-bearing particles with higher (235)U abundances in environmental samples. A polycarbonate film containing particles was prepared and placed in contact with a CR-39 plastic detector. After exposure for 28 days, the detector was etched in a NaOH solution and each uranium-bearing particle was identified through observation of the alpha tracks recorded in the detector. A portion of the film containing each uranium-bearing particle was cut out and put onto a glassy carbon planchet. The films on the planchet were decomposed through plasma ashing for subsequent uranium abundance ratio analysis with SIMS. The alpha track-SIMS analysis of 10 uranium-bearing particles in a sample taken from a nuclear facility enabled n((235)U)/n((238)U) abundance ratios in the range 0.0072-0.25 to be detected, which were significantly higher than those obtained by SIMS without alpha track detection. The duration of the whole analytical process for analysis of 10 particles was about 32 days. The detection efficiency was calculated to be 27.1±6.5%, based on the analysis of the particles in uranium reference materials. The detection limits, defined as the diameter of the particle which produces alpha tracks more than one for a 28-days exposure, were estimated to be 0.8, 0.9, 1.1, 2.1 and 3.0 μm for the particles having the same uranium abundance ratios with NBL CRM U850, U500, U350, U050 and U010 reference materials, respectively. The use of alpha track detection for subsequent SIMS analysis is an inexpensive and an efficient way to measure uranium-bearing particles with higher (235)U abundances. PMID:24468381

  19. Detailed budget analysis of HONO in central London reveals a missing daytime source

    NASA Astrophysics Data System (ADS)

    Lee, J. D.; Whalley, L. K.; Heard, D. E.; Stone, D.; Dunmore, R. E.; Hamilton, J. F.; Young, D. E.; Allan, J. D.; Laufs, S.; Kleffmann, J.

    2016-03-01

    Measurements of HONO were carried out at an urban background site near central London as part of the Clean air for London (ClearfLo) project in summer 2012. Data were collected from 22 July to 18 August 2014, with peak values of up to 1.8 ppbV at night and non-zero values of between 0.2 and 0.6 ppbV seen during the day. A wide range of other gas phase, aerosol, radiation, and meteorological measurements were made concurrently at the same site, allowing a detailed analysis of the chemistry to be carried out. The peak HONO/NOx ratio of 0.04 is seen at ˜ 02:00 UTC, with the presence of a second, daytime, peak in HONO/NOx of similar magnitude to the night-time peak, suggesting a significant secondary daytime HONO source. A photostationary state calculation of HONO involving formation from the reaction of OH and NO and loss from photolysis, reaction with OH, and dry deposition shows a significant underestimation during the day, with calculated values being close to 0, compared to the measurement average of 0.4 ppbV at midday. The addition of further HONO sources from the literature, including dark conversion of NO2 on surfaces, direct emission, photolysis of ortho-substituted nitrophenols, the postulated formation from the reaction of HO2 × H2O with NO2, photolysis of adsorbed HNO3 on ground and aerosols, and HONO produced by photosensitized conversion of NO2 on the surface increases the daytime modelled HONO to 0.1 ppbV, still leaving a significant missing daytime source. The missing HONO is plotted against a series of parameters including NO2 and OH reactivity (used as a proxy for organic material), with little correlation seen. Much better correlation is observed with the product of these species with j(NO2), in particular NO2 and the product of NO2 with OH reactivity. This suggests the missing HONO source is in some way related to NO2 and also requires sunlight. Increasing the photosensitized surface conversion rate of NO2 by a factor of 10 to a mean daytime first

  20. An optical region elemental abundance analysis of the chemically peculiar HgMn star chi Lupi

    NASA Technical Reports Server (NTRS)

    Wahlgren, Glenn M.; Adelman, Saul J.; Robinson, Richard D.

    1994-01-01

    The optical spectrum of the chemically peculiar HgMn type binary star chi Lupi has been analyzed to determine atmospheric parameters and elemental abundances. Echelle spectra were obtained with the 3.9 m Anglo-Australian telescope to exploit the extreme shape-lined nature of the spectrum. This study was undertaken in support of ultraviolet analyses currently underway that utilize echell spectra obtained with the Hubble Space Telescope. For the B9.5 V primary star we obtain T(sub eff) = 10650 K, log g = 3.9, and xi = 0 km/s, while for the A2 V secondary, T(sub eff) = 9200 K, log g = 4.0, and xi = 2 km/s. Most of the elemental abundances are typical of HgMn stars with similar T(sub eff) showing an overall iron-peak elemental abundance distribution that is basically solar in nature with enhancement of the light elements Si, P, and S, as well as all detected elements heavier than the iron group. Abundances for several elements have been determined for the first time in this star, including several of the rare-earths. The secondary star spectrum shows Am star characteristics. We also discuss the relative merits of the equivalent width and synthetic spectrum techniques in determining the elemental abundences, concluding that the synthetic spectrum technique is necessary for obtaining abundances with the utmost accuracy.

  1. DETAILED LOOP MODEL (DLM) ANALYSIS OF LIQUID SOLAR THERMOSIPHONS WITH HEAT EXCHANGERS

    SciTech Connect

    Mertol, A.; Place, W.; Webster, T.; Greif, R.

    1981-06-01

    An analytical Detailed Loop Model (DLM) has been developed to analyze the performance of solar thermosiphon water heaters with heat exchangers in storage tanks. The model has been used to study the performance of thermosiphons as a function of heat exchanger characteristics, heat transfer fluids, flow resistances, tank stratification, and tank elevation relative to the collector. The results indicate that good performance can be attained with these systems compared to thermosiphons without heat exchangers.

  2. Abundant Topological Outliers in Social Media Data and Their Effect on Spatial Analysis.

    PubMed

    Westerholt, Rene; Steiger, Enrico; Resch, Bernd; Zipf, Alexander

    2016-01-01

    Twitter and related social media feeds have become valuable data sources to many fields of research. Numerous researchers have thereby used social media posts for spatial analysis, since many of them contain explicit geographic locations. However, despite its widespread use within applied research, a thorough understanding of the underlying spatial characteristics of these data is still lacking. In this paper, we investigate how topological outliers influence the outcomes of spatial analyses of social media data. These outliers appear when different users contribute heterogeneous information about different phenomena simultaneously from similar locations. As a consequence, various messages representing different spatial phenomena are captured closely to each other, and are at risk to be falsely related in a spatial analysis. Our results reveal indications for corresponding spurious effects when analyzing Twitter data. Further, we show how the outliers distort the range of outcomes of spatial analysis methods. This has significant influence on the power of spatial inferential techniques, and, more generally, on the validity and interpretability of spatial analysis results. We further investigate how the issues caused by topological outliers are composed in detail. We unveil that multiple disturbing effects are acting simultaneously and that these are related to the geographic scales of the involved overlapping patterns. Our results show that at some scale configurations, the disturbances added through overlap are more severe than at others. Further, their behavior turns into a volatile and almost chaotic fluctuation when the scales of the involved patterns become too different. Overall, our results highlight the critical importance of thoroughly considering the specific characteristics of social media data when analyzing them spatially. PMID:27611199

  3. Assessing plantation canopy condition from airborne imagery using spectral mixture analysis and fractional abundances

    NASA Astrophysics Data System (ADS)

    Goodwin, Nicholas; Coops, Nicholas C.; Stone, Christine

    2005-05-01

    Pine plantations in Australia are subject to a range of abiotic and biotic damaging agents that affect tree health and productivity. In order to optimise management decisions, plantation managers require regular intelligence relating to the status and trends in the health and condition of trees within individual compartments. Remote sensing technology offers an alternative to traditional ground-based assessment of these plantations. Automated estimation of foliar crown health, especially in degraded crowns, can be difficult due to mixed pixels when there is low or fragmented vegetation cover. In this study we apply a linear spectral unmixing approach to high spatial resolution (50 cm) multispectral imagery to quantify the fractional abundances of the key image endmembers: sunlit canopy, shadow, and soil. A number of Pinus radiata tree crown attributes were modelled using multiple linear regression and endmember fraction images. We found high levels of significance ( r2 = 0.80) for the overall crown colour and colour of the crown leader ( r2 = 0.79) in tree crowns affected by the fungal pathogen Sphaeropsis sapinea, which produces both needle necrosis and chlorosis. Results for stands associated with defoliation and chlorosis through infestation by the aphid Essigella californica were lower with an r2 = 0.33 for crown transparency and r2 = 0.31 for proportion of crown affected. Similar analysis of data from a nitrogen deficient site produced an outcome somewhat in between the other two damaging agents. Overall the sunlit canopy image fraction has been the most important variable used in the modelling of forest condition for all damaging agents.

  4. RVC-CAL library for endmember and abundance estimation in hyperspectral image analysis

    NASA Astrophysics Data System (ADS)

    Lazcano López, R.; Madroñal Quintín, D.; Juárez Martínez, E.; Sanz Álvaro, C.

    2015-10-01

    Hyperspectral imaging (HI) collects information from across the electromagnetic spectrum, covering a wide range of wavelengths. Although this technology was initially developed for remote sensing and earth observation, its multiple advantages - such as high spectral resolution - led to its application in other fields, as cancer detection. However, this new field has shown specific requirements; for instance, it needs to accomplish strong time specifications, since all the potential applications - like surgical guidance or in vivo tumor detection - imply real-time requisites. Achieving this time requirements is a great challenge, as hyperspectral images generate extremely high volumes of data to process. Thus, some new research lines are studying new processing techniques, and the most relevant ones are related to system parallelization. In that line, this paper describes the construction of a new hyperspectral processing library for RVC-CAL language, which is specifically designed for multimedia applications and allows multithreading compilation and system parallelization. This paper presents the development of the required library functions to implement two of the four stages of the hyperspectral imaging processing chain--endmember and abundances estimation. The results obtained show that the library achieves speedups of 30%, approximately, comparing to an existing software of hyperspectral images analysis; concretely, the endmember estimation step reaches an average speedup of 27.6%, which saves almost 8 seconds in the execution time. It also shows the existence of some bottlenecks, as the communication interfaces among the different actors due to the volume of data to transfer. Finally, it is shown that the library considerably simplifies the implementation process. Thus, experimental results show the potential of a RVC-CAL library for analyzing hyperspectral images in real-time, as it provides enough resources to study the system performance.

  5. Evaluating abundance and trends in a Hawaiian avian community using state-space analysis

    USGS Publications Warehouse

    Camp, Richard J.; Brinck, Kevin W.; Gorresen, P.M.; Paxton, Eben

    2015-01-01

    Estimating population abundances and patterns of change over time are important in both ecology and conservation. Trend assessment typically entails fitting a regression to a time series of abundances to estimate population trajectory. However, changes in abundance estimates from year-to-year across time are due to both true variation in population size (process variation) and variation due to imperfect sampling and model fit. State-space models are a relatively new method that can be used to partition the error components and quantify trends based only on process variation. We compare a state-space modelling approach with a more traditional linear regression approach to assess trends in uncorrected raw counts and detection-corrected abundance estimates of forest birds at Hakalau Forest National Wildlife Refuge, Hawai‘i. Most species demonstrated similar trends using either method. In general, evidence for trends using state-space models was less strong than for linear regression, as measured by estimates of precision. However, while the state-space models may sacrifice precision, the expectation is that these estimates provide a better representation of the real world biological processes of interest because they are partitioning process variation (environmental and demographic variation) and observation variation (sampling and model variation). The state-space approach also provides annual estimates of abundance which can be used by managers to set conservation strategies, and can be linked to factors that vary by year, such as climate, to better understand processes that drive population trends.

  6. Detailed analysis of a quench bomb for the study of aluminum agglomeration in solid propellants

    NASA Astrophysics Data System (ADS)

    Gallier, S.; Kratz, J.-G.; Quaglia, N.; Fouin, G.

    2016-07-01

    A standard quench bomb (QB) - widely used to characterize condensed phase from metalized solid propellant combustion - is studied in detail. Experimental and numerical investigations proved that collected particles are mostly unburned aluminum (Al) agglomerates despite large quenching distances. Particles are actually found to quench early as propellant surface is swept by inert pressurant. Further improvements of the QB are proposed which allow measuring both Al agglomerates and alumina residue with the same setup. Finally, the results obtained on a typical aluminized ammonium perchlorate (AP) / hydroxyl-terminated polybutadiene (HTPB) propellant are briefly discussed.

  7. From detailed analysis of IO pattern of the HEP applications to benchmark of new storage solutions

    NASA Astrophysics Data System (ADS)

    Horký, Jiří; Santinelli, Roberto

    2011-12-01

    The problem of file access on the site level has been one of the main issues since the start of the WLCG project. A lot of studies have already been performed using both industry standard benchmarks and actual physicist jobs. However, such studies are typically bound to one particular LHC experiment supported on a given site and/or one type of job. In this paper, we present an application suitable for detailed study of applications' file access behavior. We have also developed an application for exact replaying of IO requests of the previously run applications. This enables to benchmark performance of solutions without a need of installing the whole working environment.

  8. Detailed spectroscopic analysis of SN 1987A: The distance to the LMC using the SEAM method

    SciTech Connect

    Mitchell, Robert C.; Baron, E.; Branch, David; Hauschildt, Peter H.; Nugent, Peter E.; Lundqvist, Peter; Blinnikov, Sergei; Pun, Chun S.J.

    2002-05-21

    Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model the observed spectra from Day 1 to Day 81 using a hydrodynamical model. We show that good agreement can be obtained at times up to about 60 days, if we allow for extended nickel mixing. Later than about 60 days the observed Balmer lines become stronger than our models can reproduce. We show that this is likely due to a more complicated distribution of gamma-rays than we allow for in our spherically symmetric calculations. We present synthetic light curves in UBVRIJHK and a synthetic bolometric light curve. Using this broad baseline of detailed spectroscopic models we find a distance modulus mu = 18.5 +/- 0.2 using the SEAM method of determining distances to supernovae. We find that the explosion time agrees with that of the neutrino burst and is constrained at 68 percent confidence to within +/- 0.9 days. We argue that the weak Balmer lines of our detailed model calculations casts doubt on the accuracy of the purely photometric EPM method. We also suggest that Type IIP supernovae will be most useful as distance indicators at early times due to a variety of effects.

  9. Human projected area factors for detailed direct and diffuse solar radiation analysis.

    PubMed

    Kubaha, K; Fiala, D; Toftum, J; Taki, A H

    2004-11-01

    Projected area factors for individual segments of the standing and sedentary human body were modelled for both direct and diffuse solar radiation using detailed 3D geometry and radiation models. The local projected area factors with respect to direct short-wave radiation are a function of the solar azimuth angle (alpha) between 0 degrees < alpha<360 degrees and the solar altitude (beta) angles between -90 degrees < beta<+90 degrees . In case of diffuse solar radiation from the isotropic sky the local human projected area factors were modelled as a function of the ground albedo (rho) ranging between 0< rho<1. The model was validated against available experimental data and showed good general agreement with projected area factors measured for both the human body as a whole and for local quantities. Scientists can use the equations to predict the inhomogeneous irradiation and absorption of direct and diffuse solar radiation and UV-radiation at surfaces of the human body. In conjunction with detailed multi-node models of human thermoregulation the equations can be used to predict the physiological implications of solar radiation and outdoor weather conditions on humans. PMID:15278684

  10. CHEMICAL ABUNDANCE ANALYSIS OF A NEUTRON-CAPTURE ENHANCED RED GIANT IN THE BULGE PLAUT FIELD

    SciTech Connect

    Johnson, Christian I.; Rich, R. Michael; McWilliam, Andrew E-mail: rmr@astro.ucla.edu E-mail: andy@obs.carnegiescience.edu

    2013-09-20

    We present chemical abundances for 27 elements ranging from oxygen to erbium in the metal-poor ([Fe/H] = –1.67) bulge red giant branch star 2MASS 18174532-3353235. The results are based on equivalent width and spectrum synthesis analyses of a high-resolution (R ∼ 30, 000) spectrum obtained with the Magellan-MIKE spectrograph. While the light (Z ∼< 30) element abundance patterns match those of similar metallicity bulge and halo stars, the strongly enhanced heavy element abundances are more similar to 'r-II' halo stars (e.g., CS 22892-052) typically found at [Fe/H] ∼< – 2.5. We find that the heaviest elements (Z ≥ 56) closely follow the scaled-solar r-process abundance pattern. We do not find evidence supporting significant s-process contributions; however, the intermediate mass elements (e.g., Y and Zr) appear to have been produced through a different process than the heaviest elements. The light and heavy element abundance patterns of 2MASS 18174532-3353235 are in good agreement with the more metal-poor r-process enhanced stars CS 22892-052 and BD +17{sup o}3248. 2MASS 18174532-3353235 also shares many chemical characteristics with the similar metallicity but comparatively α-poor Ursa Minor dwarf galaxy giant COS 82. Interestingly, the Mo and Ru abundances of 2MASS 18174532-3353235 are also strongly enhanced and follow a similar trend recently found to be common in moderately metal-poor main-sequence turn-off halo stars.

  11. The Impact of Land Abandonment on Species Richness and Abundance in the Mediterranean Basin: A Meta-Analysis

    PubMed Central

    Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam; Huntsinger, Lynn

    2014-01-01

    Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001) plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no “one-size-fits-all” conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity. PMID:24865979

  12. The impact of land abandonment on species richness and abundance in the Mediterranean Basin: a meta-analysis.

    PubMed

    Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam; Huntsinger, Lynn

    2014-01-01

    Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001) plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no "one-size-fits-all" conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity. PMID:24865979

  13. A detailed study of mean-flow solutions for stability analysis of transitional flows

    NASA Technical Reports Server (NTRS)

    Ramakrishnan, R.; Vatsa, V.; Otto, J.; Kumar, A.

    1993-01-01

    A finite-volume upwind-difference parabolized Navier-Stokes code is utilized to obtain laminar mean-flow solutions at Mach 3.5 on a half-angle cone of 5 deg at an angle-of-attack of 2 deg. A detailed study is conducted on this configuration; the main focus is the velocity profiles in the leeward and windward symmetry planes at various axial locations. Comparisons of the solution profiles are made with both a central-difference code that incorporates scalar and matrix dissipation models and another state-of-the-art upwind-difference finitevolume code. The results obtained emphasize the importance of using matrix dissipation models for schemes that require explicit artificial dissipation. These results also illustrate the accuracy and efficiency of the planeby-plane marching procedure for computing mean-flow solutions for predicting the onset of transition with linear instability.

  14. Detailed Per-residue Energetic Analysis Explains the Driving Force for Microtubule Disassembly

    PubMed Central

    Ayoub, Ahmed T.; Klobukowski, Mariusz; Tuszynski, Jack A.

    2015-01-01

    Microtubules are long filamentous hollow cylinders whose surfaces form lattice structures of αβ-tubulin heterodimers. They perform multiple physiological roles in eukaryotic cells and are targets for therapeutic interventions. In our study, we carried out all-atom molecular dynamics simulations for arbitrarily long microtubules that have either GDP or GTP molecules in the E-site of β-tubulin. A detailed energy balance of the MM/GBSA inter-dimer interaction energy per residue contributing to the overall lateral and longitudinal structural stability was performed. The obtained results identified the key residues and tubulin domains according to their energetic contributions. They also identified the molecular forces that drive microtubule disassembly. At the tip of the plus end of the microtubule, the uneven distribution of longitudinal interaction energies within a protofilament generates a torque that bends tubulin outwardly with respect to the cylinder's axis causing disassembly. In the presence of GTP, this torque is opposed by lateral interactions that prevent outward curling, thus stabilizing the whole microtubule. Once GTP hydrolysis reaches the tip of the microtubule (lateral cap), lateral interactions become much weaker, allowing tubulin dimers to bend outwards, causing disassembly. The role of magnesium in the process of outward curling has also been demonstrated. This study also showed that the microtubule seam is the most energetically labile inter-dimer interface and could serve as a trigger point for disassembly. Based on a detailed balance of the energetic contributions per amino acid residue in the microtubule, numerous other analyses could be performed to give additional insights into the properties of microtubule dynamic instability. PMID:26030285

  15. 78 FR 66929 - Intent To Conduct a Detailed Economic Impact Analysis

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... impact analysis. DATES: The Federal Register notice published on August 5, 2013 at 78 FR 47317 is...-Import Bank has recently learned that the Chinese airline will not likely operate on routes in...

  16. Abundance analysis of the supergiant stars HD 80057 and HD 80404 based on their UVES Spectra

    NASA Astrophysics Data System (ADS)

    Tanrıverdi, T.; Baştürk, Ö.

    2016-08-01

    This study presents elemental abundances of the early A-type supergiant HD 80057 and the late A-type supergiant HD 80404. High resolution and high signal-to-noise ratio spectra published by the UVES Paranal Observatory Project (Bagnulo et al., 2003)1

  17. GALA: An Automatic Tool for the Abundance Analysis of Stellar Spectra

    NASA Astrophysics Data System (ADS)

    Mucciarelli, Alessio; Pancino, Elena; Lovisi, Loredana; Ferraro, Francesco R.; Lapenna, Emilio

    2013-04-01

    GALA is a freely distributed Fortran code for automatically deriving the atmospheric parameters (temperature, gravity, microturbulent velocity, and overall metallicity) and abundances for individual species of stellar spectra using the classical method based on the equivalent widths of metallic lines. The abundances of individual spectral lines are derived by using the WIDTH9 code developed by R. L. Kurucz. GALA is designed to obtain the best model atmosphere by optimizing temperature, surface gravity, microturbulent velocity, and metallicity after rejecting the discrepant lines. Finally, it computes accurate internal errors for each atmospheric parameter and abundance. GALA is suitable for analyzing both early- and late-type stars, under the assumption of local thermodynamical equilibrium. The code permits us to obtain chemical abundances and atmospheric parameters for large stellar samples in a very short time, thus making GALA a useful tool in the epoch of multi-object spectrographs and large surveys. An extensive set of tests with both synthetic and observed spectra is performed and discussed to explore the capabilities and robustness of the code. Based on observations collected at the ESO-VLT under programs 65.L-0165, 165.L-0263, 073.D-0211, 080.D-0368, 083.D-0208, and 266.D-5655 and on data available in the ELODIE archive. This research has also made use of the SIMBAD database, operated at CDS, Strasbourg, France.

  18. GALA: AN AUTOMATIC TOOL FOR THE ABUNDANCE ANALYSIS OF STELLAR SPECTRA

    SciTech Connect

    Mucciarelli, Alessio; Lovisi, Loredana; Ferraro, Francesco R.; Lapenna, Emilio

    2013-04-01

    GALA is a freely distributed Fortran code for automatically deriving the atmospheric parameters (temperature, gravity, microturbulent velocity, and overall metallicity) and abundances for individual species of stellar spectra using the classical method based on the equivalent widths of metallic lines. The abundances of individual spectral lines are derived by using the WIDTH9 code developed by R. L. Kurucz. GALA is designed to obtain the best model atmosphere by optimizing temperature, surface gravity, microturbulent velocity, and metallicity after rejecting the discrepant lines. Finally, it computes accurate internal errors for each atmospheric parameter and abundance. GALA is suitable for analyzing both early- and late-type stars, under the assumption of local thermodynamical equilibrium. The code permits us to obtain chemical abundances and atmospheric parameters for large stellar samples in a very short time, thus making GALA a useful tool in the epoch of multi-object spectrographs and large surveys. An extensive set of tests with both synthetic and observed spectra is performed and discussed to explore the capabilities and robustness of the code.

  19. Performance evaluation of a direct computed radiography system by means of physical characterization and contrast detail analysis

    NASA Astrophysics Data System (ADS)

    Rivetti, Stefano; Lanconelli, Nico; Bertolini, Marco; Borasi, Giovanni; Acchiappati, Domenico; Burani, Aldo

    2007-03-01

    The aim of this study is to determine the performance of a direct CR reader, named "FCR Velocity U Focused Phosphor (FP)". The system is based on a CsBr columnar structured crystal, and the system's read out is based on the "linescan technology" that employs a wide-view CCD. The system's physical performance was tested by means of a quantitative analysis, with calculation of the modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE). Image quality was assessed by performing a contrast-detail analysis. The results are compared with those obtained with the well known CR system Fuji FCR XG5000, and the new one Kodak DirectView CR 975. For all the measurements the standard radiation quality RQA-5 was used. The relationship between signal amplitude and entrance air kerma is logarithmic for all the systems and the response functions were used to linearize the images before the MTF (edge method) and NPS calculations. The contrast detail analysis has been achieved by using the well known CDRAD phantom and a customized software designed for automatic computation of the contrast-detail curves. The three systems present similar MTFs, whereas the Fuji Velocity U FP system, thanks to its greater efficiency, has a better behavior in terms of NNPS, especially at low frequencies. That allows the system based on columnar phosphor to provide a better DQE. CDRAD analysis basically confirms that the structured phosphor used in the Velocity system improves the visibility of some details. This is especially true for medium and large details.

  20. Geostatistical Analysis of Spatial Variability of Mineral Abundance and Kd in Frenchman Flat, NTS, Alluvium

    SciTech Connect

    Carle, S F; Zavarin, M; Pawloski, G A

    2002-11-01

    LLNL hydrologic source term modeling at the Cambric site (Pawloski et al., 2000) showed that retardation of radionuclide transport is sensitive to the distribution and amount of radionuclide sorbing minerals. While all mineralogic information available near the Cambric site was used in these early simulations (11 mineral abundance analyses from UE-5n and 9 from RNM-l), these older data sets were qualitative in nature, with detection limits too high to accurately measure many of the important radionuclide sorbing minerals (e.g. iron oxide). Also, the sparse nature of the mineral abundance data permitted only a hypothetical description of the spatial distribution of radionuclide sorbing minerals. Yet, the modeling results predicted that the spatial distribution of sorbing minerals would strongly affect radionuclide transport. Clearly, additional data are needed to improve understanding of mineral abundances and their spatial distributions if model predictions in Frenchman Flat are to be defensible. This report evaluates new high-resolution quantitative X-Ray Diffraction (XRD) data on mineral distributions and their abundances from core samples recently collected from drill hole ER-5-4. The total of 94 samples from ER-5-4 were collected at various spacings to enable evaluation of spatial variability at a variety of spatial scales as small as 0.3 meters and up to hundreds of meters. Additional XRD analyses obtained from drillholes UE-Sn, ER-5-3, and U-11g-1 are used to augment evaluation of vertical spatial variability and permit some evaluation of lateral spatial variability. A total of 163 samples are evaluated. The overall goal of this study is to understand and characterize the spatial variation of sorbing minerals in Frenchman Flat alluvium using geostatistical techniques, with consideration for the potential impact on reactive transport of radionuclides. To achieve this goal requires an effort to ensure that plausible geostatistical models are used to

  1. First high-precision differential abundance analysis of extremely metal-poor stars

    NASA Astrophysics Data System (ADS)

    Reggiani, Henrique; Meléndez, Jorge; Yong, David; Ramírez, Ivan; Asplund, Martin

    2016-02-01

    Context. Studies of extremely metal-poor stars indicate that chemical abundance ratios [X/Fe] have a root mean square scatter as low as 0.05 dex (12%). It remains unclear whether this reflects observational uncertainties or intrinsic astrophysical scatter arising from physical conditions in the interstellar medium at early times. Aims: We measure differential chemical abundance ratios in extremely metal-poor stars to investigate the limits of precision and to understand whether cosmic scatter or observational errors are dominant. Methods: We used high-resolution (R ~ 95 000) and high signal-to-noise (S/N = 700 at 5000 Å) HIRES/Keck spectra to determine high-precision differential abundances between two extremely metal-poor stars through a line-by-line differential approach. We determined stellar parameters for the star G64-37 with respect to the standard star G64-12. We performed EW measurements for the two stars for the lines recognized in both stars and performed spectral synthesis to study the carbon abundances. Results: The differential approach allowed us to obtain errors of σ(Teff) = 27 K, σ(log g) = 0.06 dex, σ( [Fe/H] ) = 0.02 dex and σ(vt) = 0.06 km s-1. We estimated relative chemical abundances with a precision as low as σ([X/Fe]) ≈ 0.01 dex. The small uncertainties demonstrate that there are genuine abundance differences larger than the measurement errors. The observed Li difference cannot be explained by the difference in mass because the less massive star has more Li. Conclusions: It is possible to achieve an abundance precision around ≈ 0.01-0.05 dex for extremely metal-poor stars, which opens new windows on the study of the early chemical evolution of the Galaxy. Table A.1 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/586/A67

  2. Detailed Analysis of Solar Data Related to Historical Extreme Geomagnetic Storms: 1868 - 2010

    NASA Astrophysics Data System (ADS)

    Lefèvre, Laure; Vennerstrøm, Susanne; Dumbović, Mateja; Vršnak, Bojan; Sudar, Davor; Arlt, Rainer; Clette, Frédéric; Crosby, Norma

    2016-05-01

    An analysis of historical Sun-Earth connection events in the context of the most extreme space weather events of the last ˜150 years is presented. To identify the key factors leading to these extreme events, a sample of the most important geomagnetic storms was selected based mainly on the well-known aa index and on geomagnetic parameters described in the accompanying paper (Vennerstrøm et al., Solar Phys. in this issue, 2016, hereafter Paper I). This part of the analysis focuses on associating and characterizing the active regions (sunspot groups) that are most likely linked to these major geomagnetic storms.

  3. Grazing-incidence XRF analysis of layered samples: Detailed study of amplitude calculation

    NASA Astrophysics Data System (ADS)

    Miqueles, Eduardo X.; Pérez, Carlos A.; Suárez, Vanessa I.; Vescovi, Rafael F. C.

    2015-09-01

    In this article, we propose a new mathematical approach for the computation of electromagnetic wave amplitudes in grazing incidence X-ray fluorescence (GIXRF)-an analytical method for surface and near-surface layer analysis. The new contribution comes from an applied point of view, in order to have stable and fast algorithms to simulate the fluorescence intensity from a stacking of thin layer films. The calculation of transmitted/reflected amplitudes is an important part of the direct and/or inverse problem. An analysis of the amplitude versus layer thickness is also given.

  4. Mortality in vegetarians and nonvegetarians: detailed findings from a collaborative analysis of 5 prospective studies.

    PubMed

    Key, T J; Fraser, G E; Thorogood, M; Appleby, P N; Beral, V; Reeves, G; Burr, M L; Chang-Claude, J; Frentzel-Beyme, R; Kuzma, J W; Mann, J; McPherson, K

    1999-09-01

    We combined data from 5 prospective studies to compare the death rates from common diseases of vegetarians with those of nonvegetarians with similar lifestyles. A summary of these results was reported previously; we report here more details of the findings. Data for 76172 men and women were available. Vegetarians were those who did not eat any meat or fish (n = 27808). Death rate ratios at ages 16-89 y were calculated by Poisson regression and all results were adjusted for age, sex, and smoking status. A random-effects model was used to calculate pooled estimates of effect for all studies combined. There were 8330 deaths after a mean of 10.6 y of follow-up. Mortality from ischemic heart disease was 24% lower in vegetarians than in nonvegetarians (death rate ratio: 0.76; 95% CI: 0.62, 0.94; P<0.01). The lower mortality from ischemic heart disease among vegetarians was greater at younger ages and was restricted to those who had followed their current diet for >5 y. Further categorization of diets showed that, in comparison with regular meat eaters, mortality from ischemic heart disease was 20% lower in occasional meat eaters, 34% lower in people who ate fish but not meat, 34% lower in lactoovovegetarians, and 26% lower in vegans. There were no significant differences between vegetarians and nonvegetarians in mortality from cerebrovascular disease, stomach cancer, colorectal cancer, lung cancer, breast cancer, prostate cancer, or all other causes combined. PMID:10479225

  5. Detailed analysis of shake structures in the KLL Auger spectrum of H2S

    NASA Astrophysics Data System (ADS)

    Püttner, R.; Céolin, D.; Guillemin, R.; Kushawaha, R. K.; Marchenko, T.; Journel, L.; Piancastelli, M. N.; Simon, M.

    2016-04-01

    Shake processes of different origin are identified in the KLL Auger spectrum of H2S with unprecedented detail. The KLL Auger spectrum is presented together with the S 1 s-1 photoelectron spectrum including the S 1 s-1V-1n λ and S 1 s-12 p-1n λ shake-up satellites with V-1 and n λ indicating a hole in the valence shell and an unoccupied molecular orbital, respectively. By using different photon energies between 2476 and 4150 eV to record the KLL Auger spectra two different shake-up processes responsible for the satellite lines are identified. The first process is a shake-up during the Auger decay of the S 1 s-1 core hole and can be described by S 1 s-1→2 p-2V-1n λ . The second process is the Auger decay of the shake-up satellite in the ionization process leading to S 1 s-1V-1n λ →2 p-2V-1n λ transitions. By combining the results of photoelectron and Auger spectra the involved V-1n λ levels are assigned.

  6. Detailed Analysis of the Genetic and Epigenetic Signatures of iPSC-Derived Mesodiencephalic Dopaminergic Neurons

    PubMed Central

    Roessler, Reinhard; Smallwood, Sebastien A.; Veenvliet, Jesse V.; Pechlivanoglou, Petros; Peng, Su-Ping; Chakrabarty, Koushik; Groot-Koerkamp, Marian J.A.; Pasterkamp, R. Jeroen; Wesseling, Evelyn; Kelsey, Gavin; Boddeke, Erik; Smidt, Marten P.; Copray, Sjef

    2014-01-01

    Summary Induced pluripotent stem cells (iPSCs) hold great promise for in vitro generation of disease-relevant cell types, such as mesodiencephalic dopaminergic (mdDA) neurons involved in Parkinson’s disease. Although iPSC-derived midbrain DA neurons have been generated, detailed genetic and epigenetic characterizations of such neurons are lacking. The goal of this study was to examine the authenticity of iPSC-derived DA neurons obtained by established protocols. We FACS purified mdDA (Pitx3Gfp/+) neurons derived from mouse iPSCs and primary mdDA (Pitx3Gfp/+) neurons to analyze and compare their genetic and epigenetic features. Although iPSC-derived DA neurons largely adopted characteristics of their in vivo counterparts, relevant deviations in global gene expression and DNA methylation were found. Hypermethylated genes, mainly involved in neurodevelopment and basic neuronal functions, consequently showed reduced expression levels. Such abnormalities should be addressed because they might affect unambiguous long-term functionality and hamper the potential of iPSC-derived DA neurons for in vitro disease modeling or cell-based therapy. PMID:24749075

  7. Detailed analysis of the cell-inactivation mechanism by accelerated protons and light ions

    NASA Astrophysics Data System (ADS)

    Kundrát, Pavel

    2006-03-01

    A detailed study of the biological effects of diverse quality radiations, addressing their biophysical interpretation, is presented. Published survival data for V79 cells irradiated by monoenergetic protons, helium-3, carbon and oxygen ions and for CHO cells irradiated by carbon ions have been analysed using the probabilistic two-stage model of cell inactivation. Three different classes of DNA damage formed by traversing particles have been distinguished, namely severe single-track lesions which might lead to cell inactivation directly, less severe lesions where cell inactivation is caused by their combinations and lesions of negligible severity that can be repaired easily. Probabilities of single ions forming these lesions have been assessed in dependence on their linear energy transfer (LET) values. Damage induction probabilities increase with atomic number and LET. While combined lesions play a crucial role at lower LET values, single-track damage dominates in high-LET regions. The yields of single-track lethal lesions for protons have been compared with Monte Carlo estimates of complex DNA lesions, indicating that lethal events correlate well with complex DNA double-strand breaks. The decrease in the single-track damage probability for protons of LET above approximately 30 keV µm-1, suggested by limited experimental evidence, is discussed, together with the consequent differences in the mechanisms of biological effects between protons and heavier ions. Applications of the results in hadrontherapy treatment planning are outlined.

  8. A detailed analysis of theatre training activity in a UK teaching hospital.

    PubMed

    McIndoe, A K; Underwood, S M

    2000-05-01

    We examined the placement of anaesthetists in our department over a 2 yr period. Data were collected from an in-theatre system to provide details of caseload and supervision for 34,856 operations. There was wide variation between anaesthetic sub-specialties with overall supervision levels of 35% of cases for senior house officers (SHOs) and 32% for specialist registrars (SpRs). The consultant data showed the size and areas of teaching reserve in the department. We then examined individual logbooks in order to validate our data, and departmental rotas to put these data into perspective with previous attempts to quantify trainee supervision. Supervision data derived from the rota allocations showed that 86% of SHO lists and 62% of SpR lists were scheduled to be supervised. This study has described our training activity and facilitated departmental changes, as well as highlighting the need for great care in interpreting trainee supervision data acquired from different sources, particularly when comparisons are being made. PMID:10844835

  9. A detailed molecular analysis of complete bovine leukemia virus genomes isolated from B-cell lymphosarcomas.

    PubMed

    Moratorio, Gonzalo; Fischer, Sabrina; Bianchi, Sergio; Tomé, Lorena; Rama, Gonzalo; Obal, Gonzalo; Carrión, Federico; Pritsch, Otto; Cristina, Juan

    2013-01-01

    It is widely accepted that the majority of cancers result from multiple cellular events leading to malignancy after a prolonged period of clinical latency, and that the immune system plays a critical role in the control of cancer progression. Bovine leukemia virus (BLV) is an oncogenic member of the Retroviridae family. Complete genomic sequences of BLV strains isolated from peripheral blood mononuclear cells (PBMC) from cattle have been previously reported. However, a detailed characterization of the complete genome of BLV strains directly isolated from bovine tumors is much needed in order to contribute to the understanding of the mechanisms of leukemogenesis induced by BLV in cattle. In this study, we performed a molecular characterization of BLV complete genomes from bovine B-cell lymphosarcoma isolates. A nucleotide substitution was found in the glucocorticoid response element (GRE) site of the 5' long terminal repeat (5'LTR) of the BLV isolates. All amino acid substitutions in Tax previously found to be related to stimulate high transcriptional activity of 5'LTR were not found in these studies. Amino acid substitutions were found in the nucleocapsid, gp51 and G4 proteins. Premature stop-codons in R3 were observed. Few mutations or amino acid substitutions may be needed to allow BLV provirus to achieve silencing. Substitutions that favor suppression of viral expression in malignant B cells might be a strategy to circumvent effective immune attack. PMID:23506507

  10. A detailed analysis of the recombination landscape of the button mushroom Agaricus bisporus var. bisporus.

    PubMed

    Sonnenberg, Anton S M; Gao, Wei; Lavrijssen, Brian; Hendrickx, Patrick; Sedaghat-Tellgerd, Narges; Foulongne-Oriol, Marie; Kong, Won-Sik; Schijlen, Elio G W M; Baars, Johan J P; Visser, Richard G F

    2016-08-01

    The button mushroom (Agaricus bisporus) is one of the world's most cultivated mushroom species, but in spite of its economic importance generation of new cultivars by outbreeding is exceptional. Previous genetic analyses of the white bisporus variety, including all cultivars and most wild isolates revealed that crossing over frequencies are low, which might explain the lack of introducing novel traits into existing cultivars. By generating two high quality whole genome sequence assemblies (one de novo and the other by improving the existing reference genome) of the first commercial white hybrid Horst U1, a detailed study of the crossover (CO) landscape was initiated. Using a set of 626 SNPs in a haploid offspring of 139 single spore isolates and whole genome sequencing on a limited number of homo- and heterokaryotic single spore isolates, we precisely mapped all COs showing that they are almost exclusively restricted to regions of about 100kb at the chromosome ends. Most basidia of A. bisporus var. bisporus produce two spores and pair preferentially via non-sister nuclei. Combined with the COs restricted to the chromosome ends, these spores retain most of the heterozygosity of the parent thus explaining how present-day white cultivars are genetically so close to the first hybrid marketed in 1980. To our knowledge this is the first example of an organism which displays such specific CO landscape. PMID:27288752

  11. Detailed Uncertainty Analysis of the Ares I A106 Liftoff/Transition Database

    NASA Technical Reports Server (NTRS)

    Hanke, Jeremy L.

    2011-01-01

    The Ares I A106 Liftoff/Transition Force and Moment Aerodynamics Database describes the aerodynamics of the Ares I Crew Launch Vehicle (CLV) from the moment of liftoff through the transition from high to low total angles of attack at low subsonic Mach numbers. The database includes uncertainty estimates that were developed using a detailed uncertainty quantification procedure. The Ares I Aerodynamics Panel developed both the database and the uncertainties from wind tunnel test data acquired in the NASA Langley Research Center s 14- by 22-Foot Subsonic Wind Tunnel Test 591 using a 1.75 percent scale model of the Ares I and the tower assembly. The uncertainty modeling contains three primary uncertainty sources: experimental uncertainty, database modeling uncertainty, and database query interpolation uncertainty. The final database and uncertainty model represent a significant improvement in the quality of the aerodynamic predictions for this regime of flight over the estimates previously used by the Ares Project. The maximum possible aerodynamic force pushing the vehicle towards the launch tower assembly in a dispersed case using this database saw a 40 percent reduction from the worst-case scenario in previously released data for Ares I.

  12. Detailed hydrogeological analysis of a deep-seated rockslide at the Gepatsch reservoir (Klasgarten, Austria)

    NASA Astrophysics Data System (ADS)

    Strauhal, Thomas; Loew, Simon; Holzmann, Michael; Zangerl, Christian

    2016-03-01

    The hydrogeology of the deep-seated, slowly creeping Klasgarten rockslide in Austria is investigated in this study based on detailed surface and subsurface field data, laboratory analyses, and analytical and numerical simulations. Field data are derived from several deep exploration and monitoring boreholes, an exploration drift located within the rockslide, and geological and geomorphological mapping. Particular attention is given to the pore pressure measurements and their temporal and spatial variability. These pore pressure variations are controlled by a thin layer of clayey fault gouge (representing the basal shear zone of the rockslide), a high-permeability rockslide mass, and moderately fractured paragneissic bedrock. Variably saturated equivalent-continuum hydraulic conductivities and storage properties are derived from packer tests, laboratory tests and optical televiewer images. These data sets are used for two-dimensional numerical groundwater models to study the flow-field and pore-pressure variations caused by the reservoir water-level fluctuations, the transient groundwater infiltration from snowmelt and precipitation along the slope, and the exploration drift. The strongest pressure transients in the rockslide are caused by reservoir level fluctuations and not the natural groundwater recharge, even at substantial distances from the reservoir. The response times are very short and only a minor distance-dependent attenuation is observed. The results of this study are essential to analyse the hydromechanical control of the deformation behaviour of rockslides adjacent to hydropower reservoirs. Further, it helps to understand how the formation of a rockslide can change the original bedrock aquifer.

  13. CFD analysis of municipal solid waste combustion using detailed chemical kinetic modelling.

    PubMed

    Frank, Alex; Castaldi, Marco J

    2014-08-01

    Nitrogen oxides (NO x ) emissions from the combustion of municipal solid waste (MSW) in waste-to-energy (WtE) facilities are receiving renewed attention to reduce their output further. While NO x emissions are currently 60% below allowed limits, further reductions will decrease the air pollution control (APC) system burden and reduce consumption of NH3. This work combines the incorporation of the GRI 3.0 mechanism as a detailed chemical kinetic model (DCKM) into a custom three-dimensional (3D) computational fluid dynamics (CFD) model fully to understand the NO x chemistry in the above-bed burnout zones. Specifically, thermal, prompt and fuel NO formation mechanisms were evaluated for the system and a parametric study was utilized to determine the effect of varying fuel nitrogen conversion intermediates between HCN, NH3 and NO directly. Simulation results indicate that the fuel nitrogen mechanism accounts for 92% of the total NO produced in the system with thermal and prompt mechanisms accounting for the remaining 8%. Results also show a 5% variation in final NO concentration between HCN and NH3 inlet conditions, demonstrating that the fuel nitrogen intermediate assumed is not significant. Furthermore, the conversion ratio of fuel nitrogen to NO was 0.33, revealing that the majority of fuel nitrogen forms N2. PMID:25005043

  14. Preliminary evaluation of crisis-relocation fallout-shelter options. Volume 2. Detailed analysis

    SciTech Connect

    Santini, D.J.; Clinch, J.M.; Davis, F.H.; Hill, L.G.; Lynch, E.P.; Tanzman, E.A.; Wernette, D.R.

    1982-12-01

    This report presents a preliminary, detailed evaluation of various shelter options for use if the President orders crisis relocation of the US urban population because of strong expectation of a nuclear war. The availability of livable shelter space at 40 ft/sup 2/ per person (congregate-care space) by state is evaluated. Options are evaluated for construction of fallout shelters allowing 10 ft/sup 2/ per person - such shelters are designed to provide 100% survival at projected levels of radioactive fallout. The FEMA concept of upgrading existing buildings to act as fallout shelters can, in principle, provide adequate shelter throughout most of the US. Exceptions are noted and remedies proposed. In terms of upgrading existing buildings to fallout shelter status, great benefits are possible by turning away from a standard national approach and adopting a more site-specific approach. Existing FEMA research provides a solid foundation for successful crisis relocation planning, but the program can be refined by making suitable modifications in its locational, engineering, and institutionally specific elements.

  15. Detailed Analysis of Device Parameters by Means of Different Techniques in Schottky Devices

    NASA Astrophysics Data System (ADS)

    Tuğluoğlu, Nihat; Koralay, Haluk; Akgül, Kübra Bengin; Çavdar, Şükrü

    2016-08-01

    In the present work, the detailed device parameters of Au/ n-Si (100)/Al Schottky devices are calculated by means of the conductance-voltage-frequency ( G- V- f), capacitance-voltage-frequency ( C- V- f) and current-voltage ( I- V) measurements at 300 K. The structure of the device shows a good rectifying behavior. The barrier height ( {Φ_{{B}} } ) value of 0.822 eV from the C- V is determined to be higher than the 0.774 eV from the I- V. The barrier height ( {Φ_{{B}} } ) and series resistance ( {R_{{s}} } ) values of the sample determined from the Cheung and Cheung technique are 0.755 eV and 220.5 Ω, respectively. The values of the carrier donor concentration (N_{{D}}), the level of Fermi ( E_{{F}}), the lowering of image force (Δ Φ_{{b}}), the space charge layer width ( W_{{D}}) and the maximum electric field (E_{{max}}) are determined as 1.305 × 1015 cm-3, 0.258 eV, 0.0136 eV, 7.6 × 10-5 cm and 1.52 × 104 V/cm, respectively. The density of the interface state (N_{{ss}}) determined from the I- V characteristic ranges from 8.80 × 1012 eV-1 cm-2 to 5.44 × 1011 eV-1 cm-2.

  16. Detailed Compositional Analysis of the Heavily Polluted DBZ White Dwarf SDSS J073842.56+183509.06: A Window on Planet Formation?

    NASA Astrophysics Data System (ADS)

    Dufour, P.; Kilic, M.; Fontaine, G.; Bergeron, P.; Melis, C.; Bochanski, J.

    2012-04-01

    We present a new model atmosphere analysis of the most metal-contaminated white dwarf known, the DBZ SDSS J073842.56+183509.06. Using new high-resolution spectroscopic observations taken with Keck and Magellan, we determine precise atmospheric parameters and measure abundances of 14 elements heavier than helium. We also report new Spitzer mid-infrared photometric data that are used to better constrain the properties of the debris disk orbiting this star. Our detailed analysis, which combines data taken from seven different observational facilities (Galaxy Evolution Explorer, Gemini, Keck, Magellan, MMT, Sloan Digital Sky Survey, and Spitzer), clearly demonstrates that J0738+1835 is accreting large amounts of rocky terrestrial-like material that has been tidally disrupted into a debris disk. We estimate that the body responsible for the photospheric metal contamination was at least as large as Ceres, but was much drier, with less than 1% of the mass contained in the form of water ice, indicating that it formed interior to the snow line around its parent star. We also find a correlation between the abundances (relative to Mg and bulk Earth) and the condensation temperature; refractory species are clearly depleted, while the more volatile elements are possibly enhanced. This could be the signature of a body that formed in a lower temperature environment than where Earth formed. Alternatively, we could be witnessing the remains of a differentiated body that lost a large part of its outer layers. Some of the data presented herein were obtained at the W. M. Keck Observatory and the MMT Observatory. Keck is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The MMT is a joint facility of the Smithsonian Institution and the University of Arizona.

  17. Non-LTE analysis of copper abundances for the two distinct halo populations in the solar neighborhood

    NASA Astrophysics Data System (ADS)

    Yan, H. L.; Shi, J. R.; Nissen, P. E.; Zhao, G.

    2016-01-01

    Context. Two distinct halo populations were found in the solar neighborhood by a series of works. They can be clearly separated by [α/Fe] and several other elemental abundance ratios including [Cu/Fe]. Very recently, a non-local thermodynamic equilibrium (non-LTE) study revealed that relatively large departures exist between LTE and non-LTE results in copper abundance analysis. The study also showed that non-LTE effects of neutral copper vary with stellar parameters and thus affect the [Cu/Fe] trend. Aims: We aim to derive the copper abundances for the stars from the sample of Nissen & Schuster (2010) with both LTE and non-LTE calculations. Based on our results, we study the non-LTE effects of copper and investigate whether the high-α population can still be distinguished from the low-α population in the non-LTE [Cu/Fe] results. Methods: Our differential abundance ratios are derived from the high-resolution spectra collected from VLT/UVES and NOT/FIES spectrographs. Applying the MAFAGS opacity sampling atmospheric models and spectrum synthesis method, we derive the non-LTE copper abundances based on the new atomic model with current atomic data obtained from both laboratory and theoretical calculations. Results: The copper abundances determined from non-LTE calculations are increased by 0.01 to 0.2 dex depending on the stellar parameters compared with the LTE results. The non-LTE [Cu/Fe] trend is much flatter than the LTE one in the metallicity range -1.6 < [ Fe / H ] < -0.8. Taking non-LTE effects into consideration, the high- and low-α stars still show distinguishable copper abundances, which appear even more clear in a diagram of non-LTE [Cu/Fe] versus [Fe/H]. Conclusions: The non-LTE effects are strong for copper, especially in metal-poor stars. Our results confirmed that there are two distinct halo populations in the solar neighborhood. The dichotomy in copper abundance is a peculiar feature of each population, suggesting that they formed in different

  18. Detailed Analysis and Control Issues of Homogeneous Charge Compression Ignition (HCCI)

    SciTech Connect

    Aceves, Salvador M.; Flowers, Daniel L.; Martinez-Frias, Joel; Espinosa-Loza, Francisco; Dibble, Robert

    2002-08-25

    Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work.

  19. Crucial role of detailed function, task, timeline, link and human vulnerability analyses in HRA. [Human Reliability Analysis (HRA)

    SciTech Connect

    Ryan, T.G.; Haney, L.N.; Ostrom, L.T.

    1992-01-01

    This paper addresses one major cause for large uncertainties in human reliability analysis (HRA) results, that is, an absence of detailed function, task, timeline, link and human vulnerability analyses. All too often this crucial step in the HRA process is done in a cursory fashion using word of mouth or written procedures which themselves may incompletely or inaccurately represent the human action sequences and human error vulnerabilities being analyzed. The paper examines the potential contributions these detailed analyses can make in achieving quantitative and qualitative HRA results which are: (1) creditable, that is, minimize uncertainty, (2) auditable, that is, systematically linking quantitative results and qualitative information from which the results are derived, (3) capable of supporting root cause analyses on human reliability factors determined to be major contributors to risk, and (4) capable of repeated measures and being combined with similar results from other analyses to examine HRA issues transcending individual systems and facilities. Based on experience analyzing test and commercial nuclear reactors, and medical applications of nuclear technology, an iterative process is suggested for doing detailed function, task, timeline, link and human vulnerability analyses using documentation reviews, open-ended and structured interviews, direct observations, and group techniques. Finally, the paper concludes that detailed analyses done in this manner by knowledgeable human factors practitioners, can contribute significantly to the credibility, auditability, causal factor analysis, and combining goals of the HRA.

  20. THE SOLAR FLARE IRON ABUNDANCE

    SciTech Connect

    Phillips, K. J. H.; Dennis, B. R. E-mail: Brian.R.Dennis@nasa.gov

    2012-03-20

    The abundance of iron is measured from emission line complexes at 6.65 keV (Fe line) and 8 keV (Fe/Ni line) in RHESSI X-ray spectra during solar flares. Spectra during long-duration flares with steady declines were selected, with an isothermal assumption and improved data analysis methods over previous work. Two spectral fitting models give comparable results, viz., an iron abundance that is lower than previous coronal values but higher than photospheric values. In the preferred method, the estimated Fe abundance is A(Fe) = 7.91 {+-} 0.10 (on a logarithmic scale, with A(H) = 12) or 2.6 {+-} 0.6 times the photospheric Fe abundance. Our estimate is based on a detailed analysis of 1898 spectra taken during 20 flares. No variation from flare to flare is indicated. This argues for a fractionation mechanism similar to quiet-Sun plasma. The new value of A(Fe) has important implications for radiation loss curves, which are estimated.

  1. Dynamism & Detail

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    2004-01-01

    New material discovered in the study of cell research is presented for the benefit of biology teachers. Huge amounts of data are being generated in fields like cellular dynamics, and it is felt that people's understanding of the cell is becoming much more complex and detailed.

  2. Detailed analysis of the energy yield of systems with covered sheet-and-tube PVT collectors

    SciTech Connect

    Santbergen, R.; Rindt, C.C.M.; van Zolingen, R.J.Ch.; Zondag, H.A.

    2010-05-15

    Solar cells have a typical efficiency in the range of 5-20%, implying that 80% or more of the incident solar energy can be harvested in the form of heat and applied for low-temperature heating. In a PVT collector one tries to collect this heat. In this work, the electrical and thermal yield of solar domestic hot water systems with one-cover sheet-and-tube PVT collectors were considered. Objectives of the work were to understand the mechanisms determining these yields, to investigate measures to improve these yields and to investigate the yield consequences if various solar cell technologies are being used. The work was carried out using numerical simulations. A detailed quantitative understanding of all loss mechanisms was obtained, especially of those being inherent to the use of PVT collectors instead of PV modules and conventional thermal collectors. The annual electrical efficiencies of the PVT systems investigated were up to 14% (relative) lower compared to pure PV systems and the annual thermal efficiencies up to 19% (relative) lower compared to pure thermal collector systems. The loss of electrical efficiency is mainly caused by the relatively high fluid temperature. The loss of thermal efficiency is caused both by the high emissivity of the absorber and the withdrawal of electrical energy. However, both the loss of electrical and thermal efficiency can be reduced further by the application of anti-reflective coatings. The thermal efficiency can be improved by the application of a low-emissivity coating on the absorber, however at the cost of a reduced electrical efficiency. (author)

  3. Analysis and optimization of chlorocarbon incineration through use of a detailed reaction mechanism

    SciTech Connect

    Ho, W.; Booty, M.R.; Magee, R.S.; Bozzelli, J.W.

    1995-12-01

    Chemical species profiles are calculated by using a detailed reaction mechanism and a reactor code that simulates a well-mixed, three-zone incineration process. The chemical systems include CH{sub 3}Cl/CH{sub 4} and CH{sub 2}Cl{sub 2}/CH{sub 4} oxidation in air at fuel equivalence ratios {phi} from 0.8 to 1.1, with additives injected at downstream positions. Combustion is characterized for temperature, principal organic hazardous constituent (POHC), and product of incomplete combustion (PIC) levels. Major PICs comprise Cl, CL{sub 2}, CO, HOCl, and COCl{sub 2} and are calculated versus time, temperature, fuel equivalence ratio, and feed conditions. Steam, H{sub 2}O{sub 2}, O{sub 2}, air, and other species are injected as additives in the burnout region to discern changes i the combustion chemistry. Steam addition improves or decreases the CO/CO{sub 2} ratio at an additive mole fraction of 0.1. Atomic Cl is the active radical species of highest concentration in the initial high-temperature reaction zone when CH{sub 3}Cl is the POHC at a feed concentration above 1,200 ppm and {phi} {le} 1. Cl{sub 2} is found to be a major PIC under fuel-lean and stoichiometric conditions, while CO is a major PIC under fuel-rich conditions. Reduction of combined CO and Cl{sub 2} levels in the incinerator stack effluent is achieved by operation at stoichiometric conditions or slightly fuel-lean with the controlled addition of high-temperature steam.

  4. Numerical simulation and sensitivity analysis of detailed soot particle size distribution in laminar premixed ethylene flames

    SciTech Connect

    Singh, Jasdeep; Patterson, Robert I.A.; Kraft, Markus; Wang, Hai

    2006-04-15

    In this paper, the prediction of a soot model [J. Appel, H. Bockhorn, M. Frenklach, Combust. Flame 121 (2000) 122-136] is compared to a recently published set of highly detailed soot particle size distributions [B. Zhao, Z. Yang, Z. Li, M.V. Johnston, H. Wang, Proc. Combust. Inst. 30 (2005)]. A stochastic approach is used to obtain soot particle size distributions (PSDs). The key features of the measured and simulated particle size distributions are identified and used as a simple way of comparing PSDs. The sensitivity of the soot PSDs to the parameters defining parts of the soot model, such as soot inception, particle and PAH collision efficiency and enhancement, and surface activity is investigated. Incepting soot particle size is found to have a very significant effect on the small-size end of the PSDs, especially the position of the trough for a bimodal soot PSDs. A new model for the decay in the surface activity is proposed in which the activity of the soot particle depends only on the history of that particle and the local temperature in the flame. This is a first attempt to use local flame variables to define the surface aging which has major impact on the prediction of the large-size end of the PSDs. Using these modifications to the soot model it is possible to improve the agreement between some of the points of interest in the simulated and measured PSDs. The paper achieves the task to help advance the soot models to predict soot PSD in addition to soot volume fraction and number density, which has been the focus of the literature. (author)

  5. Detailed Skylab ECS consumables analysis for the interim revision flight plan (November, 1972, SL-1 launch)

    NASA Technical Reports Server (NTRS)

    Wells, C.; Kolkhorst, H. E.

    1971-01-01

    The consumables analysis was performed for the Skylab 2, 3, and 4 Preliminary Reference Interim Revision Flight Plan. The analysis and the results are based on the mission requirements as specified in the flight plan and on other available data. The results indicate that the consumables requirements for the Skylab missions allow for remaining margins (percent) of oxygen, nitrogen, and water nominal as follows: 83.5, 90.8, and 88.7 for mission SL-2; 57.1, 64.1, and 67.3 for SL-3; and 30.8, 44.3, and 46.5 for SL-4. Performance of experiment M509 as scheduled in the flight plan results in venting overboard the cluster atmosphere. This is due to the addition of nitrogen for propulsion and to the additional oxygen introduced into the cabin when the experiment is performed with the crewman suited.

  6. Detailed Analysis of Japanese Population Substructure with a Focus on the Southwest Islands of Japan

    PubMed Central

    Nishiyama, Takeshi; Kishino, Hirohisa; Suzuki, Sadao; Ando, Ryosuke; Niimura, Hideshi; Uemura, Hirokazu; Horita, Mikako; Ohnaka, Keizo; Kuriyama, Nagato; Mikami, Haruo; Takashima, Naoyuki; Mastuo, Keitaro; Guang, Yin; Wakai, Kenji; Hamajima, Nobuyuki; Tanaka, Hideo

    2012-01-01

    Uncovering population structure is important for properly conducting association studies and for examining the demographic history of a population. Here, we examined the Japanese population substructure using data from the Japan Multi-Institutional Collaborative Cohort (J-MICC), which covers all but the northern region of Japan. Using 222 autosomal loci from 4502 subjects, we investigated population substructure by estimating FST among populations, testing population differentiation, and performing principal component analysis (PCA) and correspondence analysis (CA). All analyses revealed a low but significant differentiation between the Amami Islanders and the mainland Japanese population. Furthermore, we examined the genetic differentiation between the mainland population, Amami Islanders and Okinawa Islanders using six loci included in both the Pan-Asian SNP (PASNP) consortium data and the J-MICC data. This analysis revealed that the Amami and Okinawa Islanders were differentiated from the mainland population. In conclusion, we revealed a low but significant level of genetic differentiation between the mainland population and populations in or to the south of the Amami Islands, although genetic variation between both populations might be clinal. Therefore, the possibility of population stratification must be considered when enrolling the islander population of this area, such as in the J-MICC study. PMID:22509376

  7. A National Study Assessing the Teaching & Learning of Introductory Astronomy: A Detailed Analysis of the Demographics, Gender, & Topic Domains

    NASA Astrophysics Data System (ADS)

    Schlingman, Wayne M.; Rudolph, A. L.; Prather, E. E.; Brissenden, G.; CATS

    2009-01-01

    We conducted a national study on the teaching and learning of astronomy taught in general education, non-science major, introductory astronomy courses (Astro 101). Nearly 4000 students enrolled in 69 sections of Astro 101 taught at 30 institutions around the United States completed (pre- and post-instruction) the Light and Spectroscopy Concept Inventory (LSCI) from Fall 2006 to Fall 2007 (see Rudolph et al., this meeting). This poster will provide detailed information on the demographics of the student population who participated in this study. In addition we provide details on our analysis of the relationship between participants’ gender and their normalized gains for each class section. Our analysis will also examine the normalized gains of the individual classrooms for the specific subject domains of the LSCI. We would like to thank the NSF for funding under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program.

  8. Culicoides monitoring in Belgium in 2011: analysis of spatiotemporal abundance, species diversity and Schmallenberg virus detection.

    PubMed

    DE Regge, N; DE Deken, R; Fassotte, C; Losson, B; Deblauwe, I; Madder, M; Vantieghem, P; Tomme, M; Smeets, F; Cay, A B

    2015-09-01

    In 2011, Culicoides (Diptera: Ceratopogonidae) were collected at 16 locations covering four regions of Belgium with Onderstepoort Veterinary Institute (OVI) traps and at two locations with Rothamsted suction traps (RSTs). Quantification of the collections and morphological identification showed important variations in abundance and species diversity between individual collection sites, even for sites located in the same region. However, consistently higher numbers of Culicoides midges were collected at some sites compared with others. When species abundance and diversity were analysed at regional level, between-site variation disappeared. Overall, species belonging to the subgenus Avaritia together with Culicoides pulicaris (subgenus Culicoides) were the most abundant, accounting for 80% and 96% of all midges collected with RSTs and OVI traps, respectively. Culicoides were present during most of the year, with Culicoides obsoletus complex midges found from 9 February until 27 December. Real-time reverse-transcription polymerase chain reaction screening for Schmallenberg virus in the heads of collected midges resulted in the first detection of the virus in August 2011 and identified C. obsoletus complex, Culicoides chiopterus and Culicoides dewulfi midges as putative vector species. At Libramont in the south of Belgium, no positive pools were identified. PMID:25761054

  9. Analysis of Gravity and Topographic/Bathymetric Data Over the Chicxulub Impact Structure: A Look at Details

    NASA Astrophysics Data System (ADS)

    Kinsland, G. L.; Hurtado, M.; Ceron, A.; Pope, K.; Ocampo, A.; Smythe, W.; Bedard, P.

    1996-03-01

    The Chicxulub impact feature, has been characterized as being relatively circular with a diameter of 180 Km, 240 Km, or 300 Km. To arrive at these characterizations the authors have relied for the most part upon gravity data, sparse well control, a few seismic lines and a ring of cenotes (sinkholes). We are better defining the feature by analysis of the details of the gravity and topographic/bathymetric data.

  10. Detailed Analysis of Indian Summer Monsoon Rainfall Processes with Modern/High-Quality Satellite Observations

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Kuo, Kwo-Sen; Mehta, Amita V.; Yang, Song

    2007-01-01

    We examine, in detail, Indian Summer Monsoon rainfall processes using modernhigh quality satellite precipitation measurements. The focus here is on measurements derived from three NASA cloud and precipitation satellite missionslinstruments (TRMM/PR&TMI, AQUNAMSRE, and CLOUDSATICPR), and a fourth TRMM Project-generated multi-satellite precipitation measurement dataset (viz., TRMM standard algorithm 3b42) -- all from a period beginning in 1998 up to the present. It is emphasized that the 3b42 algorithm blends passive microwave (PMW) radiometer-based precipitation estimates from LEO satellites with infi-ared (IR) precipitation estimates from a world network of CEO satellites (representing -15% of the complete space-time coverage) All of these observations are first cross-calibrated to precipitation estimates taken from standard TRMM combined PR-TMI algorithm 2b31, and second adjusted at the large scale based on monthly-averaged rain-gage measurements. The blended approach takes advantage of direct estimates of precipitation from the PMW radiometerequipped LEO satellites -- but which suffer fi-om sampling limitations -- in combination with less accurate IR estimates from the optical-infrared imaging cameras on GEO satellites -- but which provide continuous diurnal sampling. The advantages of the current technologies are evident in the continuity and coverage properties inherent to the resultant precipitation datasets that have been an outgrowth of these stable measuring and retrieval technologies. There is a wealth of information contained in the current satellite measurements of precipitation regarding the salient precipitation properties of the Indian Summer Monsoon. Using different datasets obtained from the measuring systems noted above, we have analyzed the observations cast in the form of: (1) spatially distributed means and variances over the hierarchy of relevant time scales (hourly I diurnally, daily, monthly, seasonally I intra-seasonally, and inter

  11. Detailed investigation of Long-Period activity at Campi Flegrei by Convolutive Independent Component Analysis

    NASA Astrophysics Data System (ADS)

    Capuano, P.; De Lauro, E.; De Martino, S.; Falanga, M.

    2016-04-01

    This work is devoted to the analysis of seismic signals continuously recorded at Campi Flegrei Caldera (Italy) during the entire year 2006. The radiation pattern associated with the Long-Period energy release is investigated. We adopt an innovative Independent Component Analysis algorithm for convolutive seismic series adapted and improved to give automatic procedures for detecting seismic events often buried in the high-level ambient noise. The extracted waveforms characterized by an improved signal-to-noise ratio allows the recognition of Long-Period precursors, evidencing that the seismic activity accompanying the mini-uplift crisis (in 2006), which climaxed in the three days from 26-28 October, had already started at the beginning of the month of October and lasted until mid of November. Hence, a more complete seismic catalog is then provided which can be used to properly quantify the seismic energy release. To better ground our results, we first check the robustness of the method by comparing it with other blind source separation methods based on higher order statistics; secondly, we reconstruct the radiation patterns of the extracted Long-Period events in order to link the individuated signals directly to the sources. We take advantage from Convolutive Independent Component Analysis that provides basic signals along the three directions of motion so that a direct polarization analysis can be performed with no other filtering procedures. We show that the extracted signals are mainly composed of P waves with radial polarization pointing to the seismic source of the main LP swarm, i.e. a small area in the Solfatara, also in the case of the small-events, that both precede and follow the main activity. From a dynamical point of view, they can be described by two degrees of freedom, indicating a low-level of complexity associated with the vibrations from a superficial hydrothermal system. Our results allow us to move towards a full description of the complexity of

  12. Ar-39-Ar-40 Ages of Two Nakhlites, MIL03346 and Y000593: A Detailed Analysis

    NASA Technical Reports Server (NTRS)

    Park, Jisun; Garrison, Daniel; Bogard, Donald

    2007-01-01

    Radiometric dating of martian nakhlites by several techniques have given similar ages of approx.1.2-1.4 Ga [e.g. 1, 2]. Unlike the case with shergottites, where the presence of martian atmosphere and inherited radiogenic Ar-40 produce apparent Ar-39-Ar-40 ages older than other radiometric ages, Ar-Ar ages of nakhlites are similar to ages derived by other techniques. However, even in some nakhlites the presence of trapped martian Ar produces some uncertainty in the Ar-Ar age. We present here an analysis of such Ar-Ar ages from the MIL03346 and Y000593 nakhlites.

  13. Detailed analysis of complex single molecule FRET data with the software MASH

    NASA Astrophysics Data System (ADS)

    Hadzic, Mélodie C. A. S.; Kowerko, Danny; Börner, Richard; Zelger-Paulus, Susann; Sigel, Roland K. O.

    2016-04-01

    The processing and analysis of surface-immobilized single molecule FRET (Förster resonance energy transfer) data follows systematic steps (e.g. single molecule localization, clearance of different sources of noise, selection of the conformational and kinetic model, etc.) that require a solid knowledge in optics, photophysics, signal processing and statistics. The present proceeding aims at standardizing and facilitating procedures for single molecule detection by guiding the reader through an optimization protocol for a particular experimental data set. Relevant features were determined from single molecule movies (SMM) imaging Cy3- and Cy5-labeled Sc.ai5γ group II intron molecules synthetically recreated, to test the performances of four different detection algorithms. Up to 120 different parameterizations per method were routinely evaluated to finally establish an optimum detection procedure. The present protocol is adaptable to any movie displaying surface-immobilized molecules, and can be easily reproduced with our home-written software MASH (multifunctional analysis software for heterogeneous data) and script routines (both available in the download section of www.chem.uzh.ch/rna).

  14. Detailed bifurcation analysis with a simplified model for advance heavy water reactor system

    NASA Astrophysics Data System (ADS)

    Pandey, Vikas; Singh, Suneet

    2015-01-01

    The bifurcation analysis of fixed points and limit cycles with a simplified mathematical model representing system dynamics of a boiling water reactor has been carried out, specifically parameter values for AHWR is used. The lumped parameter model that includes point reactor kinetics equation for neutron balance in the reactor core and one node model for fuel and coolant thermal hydraulics is used in the analysis. The nonlinearity due to reactivity is considered in the present model; while other nonlinearities due to heat transfer process between fuel-clad and fuel-coolant has been neglected. The system loses its stability via Hopf bifurcation as the system parameters are varied. The continuations of subcritical and supercritical Hopf points show the existence of limit point bifurcations of limit cycles (LPC). The codimension one and codimension two bifurcations of fixed points for the system have been analyzed. The stability of observed limit cycles has been analyzed by Floquet multiplier as well as by Lyapunov coefficient. The pattern of limit cycles and envelopes of limit cycles over the fixed points have been studied by numerical integrations and depicted by time history graphs.

  15. The analysis of human health risk with a detailed procedure operating in a GIS environment.

    PubMed

    Morra, P; Bagli, S; Spadoni, G

    2006-05-01

    An approach for quantifying the human health risk caused by industrial sources, which, daily or accidentally, emit dangerous pollutants able to impact on different environmental media, is introduced. The approach is performed by the HHRA-GIS tool which employs an integrated, multimedia, multi-exposure pathways and multi-receptors risk assessment model able to manage all the steps of the analysis in a georeferenced structure. Upper-bound excess lifetime cancer risk and noncarcinogenic hazards are the risk measures, the spatial distribution of which is calculated and mapped on the involved territory, once all the pathways and receptors of the study area are identified. A sensitivity analysis completes the calculations allowing to understand how risk estimates are dependent on variability in the factors contributing to risk. The last part of the paper makes use of a case study concerning a working industrial site to put in evidence in which way the designed tool can help local authorities and policy makers in managing risks and planning remedial and reduction actions. The considered geographical area is a hypothetical territory characterized by residential, agricultural and industrial zones. The presence of two sources of contamination, a municipal waste incinerator (MWI) and a contaminated site, are evaluated by the tool application. Various typologies of receptors have been taken into account, each of them characterized by different anatomical and dietary properties. The achieved results are analyzed, compared with acceptable and background values and alternatives of minor environmental impact calculated. PMID:16356549

  16. Detailed analysis of the Valdes slide: a landward facing slope failure off Chile

    NASA Astrophysics Data System (ADS)

    Anasetti, Andrea; Krastel, Sebastian; Weinrebe, Willy; Klaucke, Ingo; Bialas, Jorge

    2010-05-01

    The Chilean continental margin is a very active area interested by important tectonic movements and characterized by a fast morphological evolution. Geophysical data acquired during cruise JC 23, aboard RV JAMES COOK in March/April 2008 and previous cruises cover most of the active Chilean continental margin between 33° and 37° S. Integrated interpretation of multi-beam bathymetric, sub-bottom profiles, side-scan sonar and seismic data allowed the identification of a number of slope failures. The main topic of this project is the morphological and sedimentological analysis of the Valdes slide, a medium-sized submarine landslide offshore the city of Talcahuano (300 km south of Santiago). In contrast to most other slides along continental margins, the Valdes slide is located on the landward facing eastern slope of a submarine ridge. This setting has important implications for the associated tsunami wave field (first arrival of positive amplitude). We measured geometrical parameters of the failure and adjacent slope. The slide affected an area of 19 km2 between ~1060 m and >1700 m water depths. Its is ~ 6 km long, up to 3 km wide and involved a total sedimentary volume of about 0,8 km3. The failure process was characterized by a multiple-event and we assume its tsunami potential to be high. Using the high resolution bathymetric data and the seismic profiles along the slide deposit it was possible to reconstruct the original morphology of the area in order to understand the relation between the slide event and the structural evolution of the ridge. Through the analysis of the data and bibliographic information about the Chilean margin, we analyzed potential trigger mechanisms for the landslide. The Valdes slide is situated on a steep ridge flank. The ridge follows an elongated fault zone running app. parallel to the margin. This fault zone has a dextral component which in combination with the faults elongation results in a compressional regime that is superimposed on

  17. Detailed analysis of bathocuproine layer for organic solar cells based on copper phthalocyanine and C60

    NASA Astrophysics Data System (ADS)

    Huang, Jiang; Yu, Junsheng; Lin, Hui; Jiang, Yadong

    2009-04-01

    The electrical characteristics of double heterojunction organic solar cells with various thicknesses of bathocuproine (BCP) as an exciton-blocking layer (EBL) were studied. A theoretical analysis using optical transfer matrix theory was carried out to obtain insight into how the EBL influences light-absorbing and exciton-transporting properties in the organic layers. The results showed that by employing an 8-10 nm BCP layer exciton density was increased by 46%. By using an improved equivalent circuit model, photovoltaic characteristics were parametrized and modeled, which revealed that the thin BCP layer <10 nm did not affect the charge collection process. The mechanism of metallic cathode influence on solar cells was also discussed.

  18. Detailed behavioral analysis as a window into cross-situational word learning.

    PubMed

    Suanda, Sumarga H; Namy, Laura L

    2012-04-01

    Recent research has demonstrated that word learners can determine word-referent mappings by tracking co-occurrences across multiple ambiguous naming events. The current study addresses the mechanisms underlying this capacity to learn words cross-situationally. This replication and extension of Yu and Smith (2007) investigates the factors influencing both successful cross-situational word learning and mis-mappings. Item analysis and error patterns revealed that the co-occurrence structure of the learning environment as well as the context of the testing environment jointly affected learning across observations. Learners also adopted an exclusion strategy, which contributed conjointly with statistical tracking to performance. Implications for our understanding of the processes underlying cross-situational word learning are discussed. PMID:22257004

  19. Detailed Surface Analysis Of Incremental Centrifugal Barrel Polishing (CBP) Of Single-Crystal Niobium Samples

    SciTech Connect

    Palczewski, Ari D.; Tian, Hui; Trofimova, Olga; Reece, Charles E.

    2011-07-01

    We performed Centrifugal Barrel Polishing (CBP) on single crystal niobium samples/coupons housed in a stainless steel sample holder following the polishing recipe developed at Fermi Lab (FNAL) in 2011 \\cite{C. A. Cooper 2011}. Post CBP, the sample coupons were analyzed for surface roughness, crystal composition and structure, and particle contamination. Following the initial analysis each coupon was high pressure rinsed (HRP) and analyzed for the effectiveness of contamination removal. We were able to obtain the mirror like surface finish after the final stage of tumbling, although some defects and embedded particles remained. In addition, standard HPR appears to have little effect on removing embedded particles which remain after each tumbling step, although final polishing media removal was partially affected by standard/extended HPR.

  20. Spatio-temporal analysis techniques for detailed investigations of space storm dynamics

    NASA Astrophysics Data System (ADS)

    Vassiliadis, D.; Daglis, I. A.; Klimas, A. J.; Clauer, C. R.

    2001-09-01

    We present several spatio-temporal analysis techniques, which integrate mid-latitude ground magnetogram data and are useful in identifying key features in the ring current response. In this way we can quantify a) the intensity and spatial extent of inner magnetosphere convection, b) the intensity of the geomagnetic response to interplanetary pressure pulses, c) the penetration of the substorm current wedge to lower latitudes and d) the effect of particle injections on the ring current. The first technique creates a spatio-temporal storm "portrait" based on the axial component of the ground magnetic field H(UT;LT) [Clauer and McPherron, 1974]. Displaying the field data in UT-LT coordinates allows comparison of the activity in the inner magnetosphere. In addition to visual identification of the above features, we introduce a second technique that uses principal component analysis (PCA) of the storm portrait. PCA peaks correspond, in order of decreasing eigenvalue, to symmetric ring current, asymmetric ring current and substorm current wedge, and injections into the ring current, typically during substorms. Identification of the major PCA peaks with large-scale current systems is confirmed by correlation with and timing relative to geomagnetic indices (Dst, AL, etc). The intensity and direction of ring current injections is estimated by a bandpass filter technique for individual magnetograms. Examples using the storms of June 4, 1991, and September 26, 1998, are given. In these cases the asymmetric ring current can have a geomagnetic effect as strong as the azimuthally symmetric part meaning the majority of plasma sheet particles convecting deep into the inner magnetosphere are quickly (~2-3 hours) lost at the dayside magnetopause. On the other hand, the estimate for particle injections compared to slow convection reaches up to 30% in terms of the average geomagnetic field amplitude. Thus, individual substorms can have a significant influence on the storm-time ring

  1. A detailed analysis of film-cooling physics: Part 1 -- Streamwise injection with cylindrical holes

    SciTech Connect

    Walters, D.K.; Leylek, J.H.

    2000-01-01

    A previously documented systematic computational methodology is implemented and applied to a jet-in-crossflow problem in order to document all of the pertinent flow physics associated with a film-cooling flowfield. Numerical results are compared to experimental data for the case of a row of three-dimensional, inclined jets with length-to-diameter ratios similar to a realistic film-cooling application. A novel vorticity-based approach is included in the analysis of the flow physics. Particular attention has been paid to the downstream coolant structures and to the source and influence of counterrotating vortices in the crossflow region. It is shown that the vorticity in the boundary layers within the film hole is primarily responsible for this secondary motion. Important aspects of the study include: (1) a systematic treatment of the key numerical issues, including accurate computational modeling of the physical problem, exact geometry and high-quality grid generation techniques, higher-order numerical discretization, and accurate evaluation of turbulence model performance; (2) vorticity-based analysis and documentation of the physical mechanisms of jet-crossflow interaction and their influence on film-cooling performance; (3) a comparison of computational results to experimental data; and (4) comparison of results using a two-layer model near-wall treatment versus generalized wall functions. Solution of the steady, time-averaged Navier-Stokes equations were obtained for all cases using an unstructured/adaptive grid, fully explicit, time-marching code with multigrid, local time stepping, and residual smoothing acceleration techniques.

  2. A detailed analysis of film-cooling physics: Part I -- Streamwise injection with cylindrical holes

    SciTech Connect

    Walters, D.K.; Leylek, J.H.

    2000-01-01

    A previously documented systematic computational methodology is implemented and applied to a jet-in-crossflow problem in order to document all of the pertinent flow physics associated with a film-cooling flowfield. Numerical results are compared to experimental data for the case of a row of three-dimensional, inclined jets with length-to-diameter ratios similar to a realistic film-cooling application. A novel vorticity-based approach is included in the analysis of the flow physics. Particular attention has been paid to the downstream coolant structures and to the source and influence of counterrotating vortices in the crossflow region. It is shown that the vorticity in the boundary layers within the film hole is primarily responsible for this secondary motion. Important aspects of the study include: (1) a systematic treatment of the key numerical issues, including accurate computational modeling of the physical problem, exact geometry and the high-quality grid generation techniques, higher-order numerical discretization and accurate evaluation of turbulence model performance; (2) vorticity-based analysis and documentation of the physical mechanisms of jet-crossflow interaction and their influence on film-cooling performance; (3) a comparison of computational results to experimental data; and (4) comparison of results using a two-layer model near-wall treatment versus generalized wall functions. Solution of the steady, time-averaged Navier-Stokes equations were obtained for all cases using an unstructured/adaptive grid, fully explicit, time-marching code with multigrid, local time stepping, and residual smoothing acceleration techniques. For the case using the two-layer model, the solution was obtained with an implicit, pressure-correction solver with multigrid. The three-dimensional test case was examined for two different film-hole length-to-diameter ratios of 1.75 and 3.5, and three different blowing ratios, from 0.5 to 2.0. All of the simulations had a density

  3. Opening research sites in multicentre clinical trials within the UK: a detailed analysis of delays

    PubMed Central

    Kearney, Anna; McKay, Andrew; Hickey, Helen; Balabanova, Silviya; Marson, Anthony G; Gamble, Carrol; Williamson, Paula

    2014-01-01

    Objective To investigate the length of time taken to open UK research sites in multicentre clinical trials and to identify reasons for any delays. Design A case study, recording key milestone dates from the time a site receives ethical approval through to opening to recruitment. Delay reasons were prospectively logged by trial staff at a minimum of fortnightly periods using a coding system. Setting SANADII, a phase IV pragmatic trial, managed by the Clinical Trials Research Centre, Liverpool. The trial seeks to work with over 100 National Health Service (NHS) sites to meet its recruitment target of 1510 patients. Outcomes and analysis The primary outcome was time from Multicentre Regional Ethics Committee (MREC) approval to site opening using survival analysis. Where sites took over a specified time to reach milestones (>3 months from MREC to Site Specific Information (SSI) submission, >30 days from SSI validation to local R&D approval, or >30 days from local Research and Development (R&D) approval to opening to recruitment), the longest continuous delay during that milestone was identified. Results The median opening time for participating sites was 9.7 months (IQR 6.2 to Not Reached). SSI submission took 7 months (IQR 4.1–12.3) from ethics approval, R&D approval took 16 days (IQR 5.0–32.0) from SSI validation and site opening took 15 days (IQR 8.5–40.0) following R&D approval. The longest delays before SSI submission resulted from negotiating excess treatment costs, finalising logistics, collecting CVs and ongoing participation discussions. Conclusions While recently imposed targets are reducing the time taken for R&D departments to approve valid applications, the time taken to open UK research sites remains excessive and must be reduced. At present significant public funds are being used inefficiently in order to navigate NHS systems, challenging the resolve of trial teams and the competitiveness of the UK. PMID:25227630

  4. {sup 39}Ar Detection at the 10{sup -16} Isotopic Abundance Level with Atom Trap Trace Analysis

    SciTech Connect

    Jiang, W.; Williams, W.; Bailey, K.; O'Connor, T. P.; Mueller, P.; Davis, A. M.; Hu, S.-M.; Sun, Y. R.; Lu, Z.-T.; Purtschert, R.; Sturchio, N. C.

    2011-03-11

    Atom trap trace analysis, a laser-based atom counting method, has been applied to analyze atmospheric {sup 39}Ar (half-life=269 yr), a cosmogenic isotope with an isotopic abundance of 8x10{sup -16}. In addition to the superior selectivity demonstrated in this work, the counting rate and efficiency of atom trap trace analysis have been improved by 2 orders of magnitude over prior results. The significant applications of this new analytical capability lie in radioisotope dating of ice and water samples and in the development of dark matter detectors.

  5. Enhanced Ethanol and Biogas Production from Pinewood by NMMO Pretreatment and Detailed Biomass Analysis

    PubMed Central

    Zilouei, Hamid; Taherzadeh, Mohammad J.

    2014-01-01

    N-Methyl morpholine-N-oxide (NMMO) is an environmentally friendly and commercially applied cellulose solvent that is suggested for pretreatment of lignocelluloses to improve biofuel productions. However, the underlying mechanisms of the improvements have been poorly understood yet. In an attempt to investigate the mechanisms, pinewood powder and chips were pretreated with 85% (w/w) NMMO at 120°C for 1–15 h. The pretreatment improved ethanol production yield from 7.2% (g/g) for the untreated wood powder to 68.1–86.1% (g/g) and from 1.7% (g/g) for the untreated wood chips to 12.6–51.2% (g/g) of theoretical yield. Similarly, the biogas yields of untreated wood chips and powder were improved from 21 and 66 (mL/g volatile solids) by 3.5–6.8- and 2.6–3.4-folds, respectively. SEM micrographs indicated major increase in the wood porosity by the pretreatment, which would confirm increase in the water swelling capacity as well as enzyme adsorption. The analysis of X-ray diffraction showed considerable reduction in the cellulose crystallinity by the pretreatment, while FTIR spectroscopy results indicated reduction of lignin on the wood surface by the pretreatment. PMID:25162014

  6. Detailed river stage mapping and head gradient analysis during meander cutoff in a laboratory river

    NASA Astrophysics Data System (ADS)

    Han, Bangshuai; Endreny, Theodore A.

    2014-02-01

    Analytical models of river evolution predict meander narrowing and elongation which creates sinuosity-driven hyporheic exchange across the meander neck, by decreasing flow distance and increasing head loss. We used a laboratory river table and close range photogrammetry to map and analyze sinuosity as a driver of head gradients and hyporheic exchange during cutoff. The river valley had relatively high slopes (1.8%) and moderately cohesive sediment (10% talc, 90% sand) to facilitate cutoff, and ratios of horizontal to vertical scaling were distorted to achieve dynamic similitude (Re = 3200). Incipient to cutoff, the head gradient across the neck increased due to a narrowing neck, upstream aggradation, and downstream degradation. Longitudinal and transverse river surface slopes around the meander bend increased as the meander approached cutoff. The steep head gradient across the moderately cohesive meander neck generated seepage erosion and scour that formed a low-sinuosity avulsion. Sediment-rich flow in the avulsed channel aggraded the downstream bed and separated the active channel and oxbow lake. The limitation in geometric and dynamic similitude in the river table limits extrapolation to natural rivers, yet river evolution may involve aggradation and degradation induced channel head loss and turnover hyporheic exchange as well as seepage-induced meander neck erosion. Our submillimeter maps of meander morphology and water stage provide data to parameterize river evolution and hyporheic exchange models, and may inform analysis and mapping of field sites.

  7. Internal bores: An improved model via a detailed analysis of the energy budget

    NASA Astrophysics Data System (ADS)

    Borden, Zachary; Koblitz, Tilman; Meiburg, Eckart

    2010-11-01

    Internal bores, or hydraulic jumps, arise in many atmospheric and oceanographic phenomena. The classic single-layer hydraulic jump model accurately predicts a bore's behavior when the density difference between the expanding and contracting layer is large (i.e. water and air), but fails in the Boussinesq limit. A two-layer model, where mass is conserved separately in each layer and momentum is conserved globally, does a much better job but requires for closure an assumption about the loss of energy across a bore. Through the use of 2D direct numerical simulations, we show that there is a transfer of energy from the contracting to the expanding layer due to viscous stresses at the interface. Based on the simulation results, we propose a two-layer model that provides an accurate bore velocity as function of all geometrical parameters, as well as the Reynolds and Schmidt numbers. We also extend our analysis to non-Boussinesq internal bores to bridge the gap between the single and two-layer models.

  8. A detailed comparative analysis of codon usage bias in Zika virus.

    PubMed

    Cristina, Juan; Fajardo, Alvaro; Soñora, Martín; Moratorio, Gonzalo; Musto, Héctor

    2016-09-01

    Zika virus (ZIKV) is a member of the family Flaviviridae and its genome consists of a single-stranded positive sense RNA molecule with 10,794 nucleotides. Clinical manifestations of disease caused by ZIKV infection range from asymptomatic cases to an influenza-like syndrome. There is an increasing concern about the possible relation among microcephaly and ZIKV infection. To get insight into the relation of codon usage among viruses and their hosts is extremely important to understand virus survival, fitness, evasion from host's immune system and evolution. In this study, we performed a comprehensive analysis of codon usage and composition of ZIKV. The overall codon usage among ZIKV strains is similar and slightly biased. Different codon preferences in ZIKV genes in relation to codon usage of human, Aedes aegypti and Aedes albopictus genes were found. Most of the highly frequent codons are A-ending, which strongly suggests that mutational bias is the main force shaping codon usage in this virus. G+C compositional constraint as well as dinucleotide composition also influence the codon usage of ZIKV. The results of these studies suggest that the emergence of ZIKV outside Africa, in the Pacific and the Americas may also be reflected in ZIKV codon usage. No significant differences were found in codon usage among strains isolated from microcephaly cases and the rest of strains from the Asian cluster enrolled in these studies. PMID:27449601

  9. Detailed chronological analysis of microevolution events in herds infected persistently by Mycobacterium bovis.

    PubMed

    Navarro, Yurena; Romero, Beatriz; Bouza, Emilio; Domínguez, Lucas; de Juan, Lucía; García-de-Viedma, Darío

    2016-02-01

    Various studies have analyzed microevolution events leading to the emergence of clonal variants in human infections by Mycobacterium tuberculosis. However, microevolution events in animal tuberculosis remain unknown. We performed a systematic analysis of microevolution events in eight herds that were chronically infected by Mycobacterium bovis for more than 12 months. We analyzed 88 animals using a systematic screening procedure based on discriminatory MIRU-VNTR genotyping at sequential time points during the infection. Microevolution was detected in half of the herds studied. Emergence of clonal variants did not require long infection periods or a high number of infected animals in the herd. Microevolution was not restricted to strains from specific spoligotypes, and the subtle variations detected involved different MIRU loci. The genetic locations of the subtle genotypic variations recorded in the clonal variants indicated potential functional significance. This finding was consistent with the dynamics of some clonal variants, which outcompeted the original strains, suggesting an advantageous phenotype. Our data constitute a first step in defining the thresholds of variability to be tolerated in molecular epidemiology studies of M. bovis. We could therefore ensure that related clonal variants emerging as a result of microevolution events are not going to be misinterpreted as unrelated isolates. PMID:26790941

  10. Impact of influenza vaccine formulation with a detailed analysis of the cytokine response.

    PubMed

    Szyszko, E; Brokstad, K; Cox, R J; Hovden, A-O; Madhun, A; Haaheim, L R

    2006-11-01

    Vaccination provides the most effective method of limiting the impact of influenza. Inactivated influenza vaccines are available in three formulations and more information needs to be generated on how antigen presented in different vaccine formulations influences the subsequent immune response. In the present study, we have investigated the effect of two different influenza vaccine formulations on the resulting antibody and cytokine responses and compared these responses with influenza infection. Mice were vaccinated intramuscularly with one or two doses of whole or split virus vaccine or alternatively intranasally infected with influenza virus. Lymphocytes were isolated from spleen cells and stimulated in vitro for 24 or 72 h for analysis of cytokine profile at the gene expression and at the protein level. Additionally, whole blood was collected and the serum antibody response investigated by haemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA). We found that one dose of whole virus vaccine induced higher antibody and cytokine responses and thus was more immunogenic in unprimed mice than split virus vaccine. Whole virus vaccine induced a strong IFN-gamma (type 1) immune response after one dose of vaccine and a more mixed cytokine response after the second dose. Split virus vaccine induced a type 2 response, particularly after two vaccine doses. Our results show that two doses of vaccine (both vaccine formulation) were more effective in induction of Th2 type of cytokines and thus indicate that both the formulation and also the number of vaccine doses substantially influences the magnitude and quality of the immune response. PMID:17032238

  11. Detailed Analysis of Peri-Procedural Strokes in Patients Undergoing Intracranial Stenting in SAMMPRIS

    PubMed Central

    Fiorella, David; Derdeyn, Colin P; Lynn, Michael J; Barnwell, Stanley L; Hoh, Brian L.; Levy, Elad I.; Harrigan, Mark R.; Klucznik, Richard P.; McDougall, Cameron G.; Pride, G. Lee; Zaidat, Osama O.; Lutsep, Helmi L.; Waters, Michael F.; Hourihane, J. Maurice; Alexandrov, Andrei V.; Chiu, David; Clark, Joni M.; Johnson, Mark D.; Torbey, Michel T.; Rumboldt, Zoran; Cloft, Harry J.; Turan, Tanya N.; Lane, Bethany F.; Janis, L. Scott; Chimowitz, Marc I.

    2012-01-01

    Background and Purpose Enrollment in the SAMMPRIS trial was halted due to the high risk of stroke or death within 30 days of enrollment in the percutaneous transluminal angioplasty and stenting (PTAS) arm relative to the medical arm. This analysis focuses on the patient and procedural factors that may have been associated with peri-procedural cerebrovascular events in the trial. Methods Bivariate and multivariate analyses were performed to evaluate whether patient and procedural variables were associated with cerebral ischemic or hemorrhagic events occurring within 30 days of enrollment (termed peri-procedural) in the PTAS arm. Results Of 224 patients randomized to PTAS, 213 underwent angioplasty alone (n=5) or with stenting (n=208). Of these, 13 had hemorrhagic strokes (7 parenchymal, 6 subarachnoid), 19 had ischemic stroke, and 2 had cerebral infarcts with temporary signs (CITS) within the peri-procedural period. Ischemic events were categorized as perforator occlusions (13), embolic (4), mixed perforator and embolic (2), and delayed stent occlusion (2). Multivariate analyses showed that higher percent stenosis, lower modified Rankin score, and clopidogrel load associated with an activated clotting time above the target range were associated (p ≤ 0.05) with hemorrhagic stroke. Non-smoking, basilar artery stenosis, diabetes, and older age were associated (p ≤ 0.05) with ischemic events. Conclusions Peri-procedural strokes in SAMMPRIS had multiple causes with the most common being perforator occlusion. Although risk factors for peri-procedural strokes could be identified, excluding patients with these features from undergoing PTAS to lower the procedural risk would limit PTAS to a small subset of patients. Moreover, given the small number of events, the present data should be used for hypothesis generation rather than to guide patient selection in clinical practice. PMID:22984008

  12. Detailed microstructure analysis of as-deposited and etched porous ZnO films

    NASA Astrophysics Data System (ADS)

    Shang, Congcong; Thimont, Yohann; Barnabé, Antoine; Presmanes, Lionel; Pasquet, Isabelle; Tailhades, Philippe

    2015-07-01

    ZnO nanostructured materials in thin film forms are of particular interest for photovoltaic or photocatalysis processes but they suffer from a lack of simple methods for optimizing their microstructure. We have demonstrated that microporous ZnO thin films with optimized inter grain accessibility can be produce by radio frequency magnetron sputtering process and chemical etching with 2.75 mM HCl solution for different duration. The as-deposited ZnO thin films were first characterized in terms of structure, grain size, inter grain space, open cavity depth and total thickness of the film by XRD, AFM, SEM, profilometry and optical measurements. A specific attention was dedicated to the determination of the surface enhancement factor (SEF) by using basic geometrical considerations and images treatments. In addition, the porous fraction and its distribution in the thickness have been estimated thanks to the optical simulation of the experimental UV-Visible-IR spectrums using the Bruggeman dielectric model and cross section SEM images analysis respectively. This study showed that the microstructure of the as-deposited films consists of a dense layer covered by a porous upper layer developing a SEF of 12-13 m2 m-2. This two layers architecture is not modified by the etching process. The etching process only affects the upper porous layer in which the overall porosity and the inter-grain space increase with the etching duration. Column diameter and total film thickness decrease at the same time when the films are soaked in the HCl bath. The microporous structure obtained after the etching process could generate a great interest for the interfaces electronic exchanges for solar cells, photocatalysis and gas sensors applications.

  13. Academic detailing.

    PubMed

    Shankar, P R; Jha, N; Piryani, R M; Bajracharya, O; Shrestha, R; Thapa, H S

    2010-01-01

    There are a number of sources available to prescribers to stay up to date about medicines. Prescribers in rural areas in developing countries however, may not able to access some of them. Interventions to improve prescribing can be educational, managerial, and regulatory or use a mix of strategies. Detailing by the pharmaceutical industry is widespread. Academic detailing (AD) has been classically seen as a form of continuing medical education in which a trained health professional such as a physician or pharmacist visits physicians in their offices to provide evidence-based information. Face-to-face sessions, preferably on an individual basis, clear educational and behavioural objectives, establishing credibility with respect to objectivity, stimulating physician interaction, use of concise graphic educational materials, highlighting key messages, and when possible, providing positive reinforcement of improved practices in follow-up visits can increase success of AD initiatives. AD is common in developed countries and certain examples have been cited in this review. In developing countries the authors have come across reports of AD in Pakistan, Sudan, Argentina and Uruguay, Bihar state in India, Zambia, Cuba, Indonesia and Mexico. AD had a consistent, small but potentially significant impact on prescribing practices. AD has much less resources at its command compared to the efforts by the industry. Steps have to be taken to formally start AD in Nepal and there may be specific hindering factors similar to those in other developing nations. PMID:21209521

  14. A detailed description of the uncertainty analysis for High Area Ratio Rocket Nozzle tests at the NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth J.; Dieck, Ronald H.; Chuang, Isaac

    1987-01-01

    A preliminary uncertainty analysis has been performed for the High Area Ratio Rocket Nozzle test program which took place at the altitude test capsule of the Rocket Engine Test Facility at the NASA Lewis Research Center. Results from the study establish the uncertainty of measured and calculated parameters required for the calculation of rocket engine specific impulse. A generalized description of the uncertainty methodology used is provided. Specific equations and a detailed description of the analysis are presented. Verification of the uncertainty analysis model was performed by comparison with results from the experimental program's data reduction code. Final results include an uncertainty for specific impulse of 1.30 percent. The largest contributors to this uncertainty were calibration errors from the test capsule pressure and thrust measurement devices.

  15. A detailed description of the uncertainty analysis for high area ratio rocket nozzle tests at the NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth J.; Dieck, Ronald H.; Chuang, Isaac

    1987-01-01

    A preliminary uncertainty analysis was performed for the High Area Ratio Rocket Nozzle test program which took place at the altitude test capsule of the Rocket Engine Test Facility at the NASA Lewis Research Center. Results from the study establish the uncertainty of measured and calculated parameters required for the calculation of rocket engine specific impulse. A generalized description of the uncertainty methodology used is provided. Specific equations and a detailed description of the analysis is presented. Verification of the uncertainty analysis model was performed by comparison with results from the experimental program's data reduction code. Final results include an uncertainty for specific impulse of 1.30 percent. The largest contributors to this uncertainty were calibration errors from the test capsule pressure and thrust measurement devices.

  16. Elemental abundance analysis of the early-type members of the open cluster M6: Preliminary results

    NASA Astrophysics Data System (ADS)

    Kııçoǧlu, T.; Monier, R.; Fossati, L.

    2014-11-01

    Differences in chemical composition among main sequence stars within a given cluster are probably due to differences in their masses and other effects such as radiative diffusion, magnetic field, rotation, mixing mechanisms, mass loss, accretion and multiplicity. The early type main-sequence members of open clusters of different ages support studies of the competition between radiative diffusion and mixing mechanisms. We have analysed low- and high-resolution spectra covering the spectral range λ 4500-5840 Å of late B-, A- and F-type members of the open cluster M6 (age ˜100 Myr). The spectra were obtained with the FLAMES/GIRAFFE spectrograph mounted at UT2, the 8-m VLT telescope. The effective temperatures, surface gravities and microturbulent velocities of the stars were derived from both photometric and spectral methods. We have also performed a chemical abundance analysis using synthetic spectra. Abundances were determined for the elements C, O, Mg, Si, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Y and Ba. The star-to-star variations in element abundances among the members of M6 are discussed.

  17. A rapid method for depletion of Rubisco from soybean (Glycine max) leaf for proteomic analysis of lower abundance proteins.

    PubMed

    Krishnan, Hari B; Natarajan, Savithiry S

    2009-12-01

    2-DE analysis of complex plant proteomes has limited dynamic resolution because only abundant proteins can be detected. Proteomic assessment of the low abundance proteins within leaf tissue is difficult when it is comprised of 30-50% of the CO(2) fixation enzyme Rubisco. Resolution can be improved through depletion of Rubisco using fractionation techniques based upon different physiological or biochemical principles. We have developed a fast and simple fractionation technique using 10 mM Ca(2+) and 10 mM phytate to precipitate Rubisco from soybean leaf soluble protein extract. This method is not only rapid, but also inexpensive, and capable of removing 85% of the extremely abundant Rubisco enzyme from soybean leaf soluble protein extract. This method allowed for roughly 230 previously inconspicuous protein spots in soybean leaf to be more easily detectable (3-fold increase in vol%) using fluorescent detection and allowed 28 phosphorylated proteins previously undetected, to be isolated and identified by MALDI-TOF-MS. PMID:19766275

  18. Volcano Hazard Tracking and Disaster Risk Mitigation: A Detailed Gap Analysis from Data-Collection to User Implementation

    NASA Astrophysics Data System (ADS)

    Faied, D.; Sanchez, A.

    2009-04-01

    Volcano Hazard Tracking and Disaster Risk Mitigation: A Detailed Gap Analysis from Data-Collection to User Implementation Dohy Faied, Aurora Sanchez (on behalf of SSP08 VAPOR Project Team) Dohy.Faied@masters.isunet.edu While numerous global initiatives exist to address the potential hazards posed by volcanic eruption events and assess impacts from a civil security viewpoint, there does not yet exist a single, unified, international system of early warning and hazard tracking for eruptions. Numerous gaps exist in the risk reduction cycle, from data collection, to data processing, and finally dissemination of salient information to relevant parties. As part of the 2008 International Space University's Space Studies Program, a detailed gap analysis of the state of volcano disaster risk reduction was undertaken, and this paper presents the principal results. This gap analysis considered current sensor technologies, data processing algorithms, and utilization of data products by various international organizations. Recommendations for strategies to minimize or eliminate certain gaps are also provided. In the effort to address the gaps, a framework evolved at system level. This framework, known as VIDA, is a tool to develop user requirements for civil security in hazardous contexts, and a candidate system concept for a detailed design phase. VIDA also offers substantial educational potential: the framework includes a centralized clearinghouse for volcanology data which could support education at a variety of levels. Basic geophysical data, satellite maps, and raw sensor data are combined and accessible in a way that allows the relationships between these data types to be explored and used in a training environment. Such a resource naturally lends itself to research efforts in the subject but also research in operational tools, system architecture, and human/machine interaction in civil protection or emergency scenarios.

  19. Organization and Detailed Parcellation of Human Hippocampal Head and Body Regions Based on a Combined Analysis of Cyto- and Chemoarchitecture.

    PubMed

    Ding, Song-Lin; Van Hoesen, Gary W

    2015-10-15

    The hippocampal formation (HF) is one of the hottest regions in neuroscience because it is critical to learning, memory, and cognition, while being vulnerable to many neurological and mental disorders. With increasing high-resolution imaging techniques, many scientists have started to use distinct landmarks along the anterior-posterior axis of HF to allow segmentation into individual subfields in order to identify specific functions in both normal and diseased conditions. These studies urgently call for more reliable and accurate segmentation of the HF subfields DG, CA3, CA2, CA1, prosubiculum, subiculum, presubiculum, and parasubiculum. Unfortunately, very limited data are available on detailed parcellation of the HF subfields, especially in the complex, curved hippocampal head region. In this study we revealed detailed organization and parcellation of all subfields of the hippocampal head and body regions on the base of a combined analysis of multiple cyto- and chemoarchitectural stains and dense sequential section sampling. We also correlated these subfields to macro-anatomical landmarks, which are visible on magnetic resonance imaging (MRI) scans. Furthermore, we created three versions of the detailed anatomic atlas for the hippocampal head region to account for brains with four, three, or two hippocampal digitations. These results will provide a fundamental basis for understanding the organization, parcellation, and anterior-posterior difference of human HF, facilitating accurate segmentation and measurement of HF subfields in the human brain on MRI scans. PMID:25872498

  20. NSTX Disruption Simulations of Detailed Divertor and Passive Plate Models by Vector Potential Transfer from OPERA Global Analysis Results

    SciTech Connect

    P. H. Titus, S. Avasaralla, A.Brooks, R. Hatcher

    2010-09-22

    The National Spherical Torus Experiment (NSTX) project is planning upgrades to the toroidal field, plasma current and pulse length. This involves the replacement of the center-stack, including the inner legs of the TF, OH, and inner PF coils. A second neutral beam will also be added. The increased performance of the upgrade requires qualification of the remaining components including the vessel, passive plates, and divertor for higher disruption loads. The hardware needing qualification is more complex than is typically accessible by large scale electromagnetic (EM) simulations of the plasma disruptions. The usual method is to include simplified representations of components in the large EM models and attempt to extract forces to apply to more detailed models. This paper describes a more efficient approach of combining comprehensive modeling of the plasma and tokamak conducting structures, using the 2D OPERA code, with much more detailed treatment of individual components using ANSYS electromagnetic (EM) and mechanical analysis. This capture local eddy currents and resulting loads in complex details, and allows efficient non-linear, and dynamic structural analyses.

  1. Numerical modeling and analysis of static and ballistic behavior of multilayered/multiphase composite materials using detailed microstructural discretization

    NASA Astrophysics Data System (ADS)

    Jovicic, Jovan M.

    The goal of this work is to analyze the static and ballistic performance of multi material systems using a detailed finite element analysis. As more complex materials systems are introduced in engineering practice, the design engineer faces the dilemma of utilizing homogenization techniques or detailed numerical models. The latter offers a number of advantages, such as the ability to introduce separate constitutive laws and failure criteria for each phase, at the expense of computation cost. This is particularly important in ballistic performance of armor where the sequence of failure of each phase plays a major role in the energy absorption. Here, we present an automatic geometry generation algorithm for composite materials that can generate complex composite geometries spanning several unit cells. This capability is utilized to study the following phenomena: (1) Static behavior of textile composites: A comparative study of textile composites with different reinforcement architecture that shows the origins of non-linearity and the dependence of elastic parameters on the geometry of the unit cell; (2) Impact behavior of textile composites: The role of textile architecture in impact energy absorption; (3) Ballistic properties of ceramic sphere composites with textile composite backings. A detailed study of a new gradient design concept is presented using a full finite element discretization method that shows that although ceramic spheres embedded in epoxy exhibit a slightly lower energy absorption than the monolithic ceramic at the same areal density, they provide the advantage of ease of complex shape conformable manufacturing. A comparison with ballistic experiments on such material demonstrates that the analysis captures several aspects of this phenomenon.

  2. Accurate and homogeneous abundance patterns in solar-type stars of the solar neighbourhood: a chemo-chronological analysis

    NASA Astrophysics Data System (ADS)

    da Silva, R.; Porto de Mello, G. F.; Milone, A. C.; da Silva, L.; Ribeiro, L. S.; Rocha-Pinto, H. J.

    2012-06-01

    Aims: We report the derivation of abundances of C, Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, Ce, Nd, and Sm in a sample of 25 solar-type stars of the solar neighbourhood, correlating the abundances with the stellar ages, kinematics, and orbital parameters. Methods: The spectroscopic analysis, based on data of high resolution and high signal-to-noise ratio, was differential to the Sun and applied to atomic line equivalent widths supplemented by the spectral synthesis of C and C2 features. We also performed a statistical study by using the method of tree clustering analysis, searching for groups of stars sharing similar elemental abundance patterns. We derived the stellar parameters from various criteria, with average errors of 30 K, 0.13 dex, and 0.05 dex, respectively, for Teff, log g, and [Fe/H]. The average error of the [X/Fe] abundance ratios is 0.06 dex. Ages were derived from theoretical HR diagrams and membership of the stars in known kinematical moving groups. Results: We identified four stellar groups: one having, on average, over-solar abundances (⟨[X/H]⟩ = +0.26 dex), another with under-solar abundances (⟨ [X/H] ⟩ = -0.24 dex), and two with intermediate values (⟨ [X/H] ⟩ = -0.06 and +0.06 dex) but with distinct chemical patterns. Stars sharing solar metallicity, age, and Galactic orbit possibly have non-solar abundance ratios, a possible effect either of chemical heterogeneity in their natal clouds or migration. A trend of [Cu/Fe] with [Ba/Fe] seems to exist, in agreement with previous claims in the literature, and maybe also of [Sm/Fe] with [Ba/Fe]. No such correlation involving C, Na, Mn, and Zn is observed. The [X/Fe] ratios of various elements show significant correlations with age. [Mg/Fe], [Sc/Fe], and [Ti/Fe] increase with age. [Mn/Fe] and [Cu/Fe] display a more complex behaviour, first increasing towards younger stars up to the solar age, and then decreasing, a result we interpret as possibly related to time

  3. Assessment of Invasive Breast Cancer Heterogeneity Using Whole-Tumor Magnetic Resonance Imaging Texture Analysis: Correlations With Detailed Pathological Findings.

    PubMed

    Ko, Eun Sook; Kim, Jae-Hun; Lim, Yaeji; Han, Boo-Kyung; Cho, Eun Yoon; Nam, Seok Jin

    2016-01-01

    There is no study that investigates the potential correlation between the heterogeneity obtained from texture analysis of medical images and the heterogeneity observed from histopathological findings. We investigated whether texture analysis of magnetic resonance images correlates with histopathological findings.Seventy-five patients with estrogen receptor positive invasive ductal carcinoma who underwent preoperative breast magnetic resonance imaging (MRI) were included. Tumor entropy and uniformity were determined on T2- and contrast-enhanced T1-weighted subtraction images under different filter levels. Two pathologists evaluated the detailed histopathological findings of the tumors including tumor cellularity, dominant stroma type, central scar, histologic grade, extensive intraductal component (EIC), and lymphovascular invasion. Entropy and uniformity values on both T2- and contrast-enhanced T1-weighted subtraction images were compared with detailed pathological findings.In a multivariate analysis, entropy significantly increased only on unfiltered T2-weighted images (P = 0.013). Tumor cellularity and predominant stroma did not affect the uniformity or entropy on both T2- and contrast-enhanced T1-weighted subtraction images. High histologic grades showed increased uniformity and decreased entropy on contrast-enhanced T1-weighted subtraction images, whereas the opposite tendency was observed on T2-weighted images. Invasive ductal carcinoma with an EIC or lymphovascular invasion only affected the contrast-enhanced T1-weighted subtraction images, through increased uniformity and decreased entropy. The best uniformity results were recorded on T2- and contrast-enhanced T1-weighted subtraction images at a filter level of 0.5. Entropy showed the best results at a filter level of 0.5 on contrast-enhanced T1-weighted subtraction images. However, on T2-weighted images, an ideal model was achieved on unfiltered images.MRI texture analysis correlated with pathological

  4. DERIVING PLASMA DENSITIES AND ELEMENTAL ABUNDANCES FROM SERTS DIFFERENTIAL EMISSION MEASURE ANALYSIS

    SciTech Connect

    Schmelz, J. T.; Kimble, J. A.; Saba, J. L. R.

    2012-09-20

    We use high-resolution spectral emission line data obtained by the SERTS instrument during three rocket flights to demonstrate a new approach for constraining electron densities of solar active region plasma. We apply differential emission measure (DEM) forward-fitting techniques to characterize the multithermal solar plasma producing the observed EUV spectra, with constraints on the high-temperature plasma from the Yohkoh Soft X-ray Telescope. In this iterative process, we compare line intensities predicted by an input source distribution to observed line intensities for multiple iron ion species, and search a broad range of densities to optimize {chi}{sup 2} simultaneously for the many available density-sensitive lines. This produces a density weighted by the DEM, which appears to be useful for characterizing the bulk of the emitting plasma over a significant range of temperature. This 'DEM-weighted density' technique is complementary to the use of density-sensitive line ratios and less affected by uncertainties in atomic data and ionization fraction for any specific line. Once the DEM shape and the DEM-weighted density have been established from the iron lines, the relative elemental abundances can be determined for other lines in the spectrum. We have also identified spectral lines in the SERTS wavelength range that may be problematic.

  5. Copy Number Analysis of the Murine Platelet Proteome Spanning the Complete Abundance Range*

    PubMed Central

    Zeiler, Marlis; Moser, Markus; Mann, Matthias

    2014-01-01

    Knowledge of the identity and quantity of expressed proteins of a cell type is a prerequisite for a complete understanding of its molecular functions. Mass-spectrometry-based proteomics has allowed the identification of the entire protein complement of yeast and the close-to-complete set of proteins expressed in mammalian cell lines. Using recent technological advances, we here characterized the proteome of murine platelets, key actors in mediating hemostasis and thrombosis. We accurately measured the absolute protein concentrations of 13 platelet proteins using SILAC-protein epitope signature tags and used them as reference points to estimate the copy numbers of all proteins of the platelet proteome. To distinguish contaminants such as plasma or erythrocyte proteins from true platelet proteins, we monitored protein abundance profiles across multiple purification steps. In total, we absolutely quantified 4,400 platelet proteins, with estimated copy numbers ranging from less than 10 to about a million per cell. Stoichiometries derived from our data correspond well with previous studies. Our study provides a close-to-complete reference map of platelet proteins that will be useful to the community, for instance, for interpreting mouse models of human platelet diseases. PMID:25205226

  6. Proteome analysis of abundant proteins extracted from the leaf of Gynura procumbens (Lour.) Merr.

    PubMed

    Hew, Chaw-Sen; Gam, Lay-Harn

    2011-12-01

    Gynura procumbens (Lour.) Merr. is a traditionally used medicinal plant to decrease cholesterol level, reduce high blood pressure, control diabetics, and for treatment of cancer. In our present study, a proteomic approach was applied to study the proteome of the plant that had never analyzed before. We have identified 92 abundantly expressed proteins from the leaves of G. procumbens (Lour.) Merr. Amongst the identified proteins was miraculin, a taste-masking agent with high commercial value. Miraculin made up ∼0.1% of the total protein extracted; the finding of miraculin gave a great commercial value to G. procumbens (Lour.) Merr. as miraculin's natural source is limited while the production of recombinant miraculin faced challenges of not being able to exhibit the taste-masking effect as in the natural miraculin. We believe the discovery of miraculin in G. procumbens (Lour.) Merr., provides commercial feasibility of miraculin in view of the availability of G. procumbens (Lour.) Merr. that grow wildly and easily in tropical climate. PMID:21938418

  7. Phylogenetic analysis of microalgae based on highly abundant proteins using mass spectrometry.

    PubMed

    Lee, Hae-Won; Roh, Seong Woon; Cho, Kichul; Kim, Kil-Nam; Cha, In-Tae; Yim, Kyung June; Song, Hye Seon; Nam, Young-Do; Oda, Tatsuya; Chung, Young-Ho; Kim, Soo Jung; Choi, Jong-Soon; Kim, Daekyung

    2015-01-01

    The blooms of toxic phototrophic microorganisms, such as microalgae and cyanobacteria, which are typically found in freshwater and marine environments, are becoming more frequent and problematic in aquatic systems. Due to accumulation of toxic algae, harmful algal blooms (HABs) exert negative effects on aquatic systems. Therefore, rapid detection of harmful microalgae is important for monitoring the occurrence of HABs. Mass spectrometry-based methods have become sensitive, specific techniques for the identification and characterization of microorganisms. Matrix-assisted laser desorption/ionization (MALDI) with time-of-flight (TOF) mass spectrometry (MS) allows us to measure a unique molecular fingerprint of highly abundant proteins in a microorganism and has been used for the rapid, accurate identification of bacteria and fungi in clinical microbiology. Here, we tested the specificity of MALDI-TOF MS using microalgal strains (Heterocapsa, Alexandrium, Nannochloropsis, Chaetoceros, Chlorella, and Dunaliella spp.). Our research suggested that this method was comparable in terms of the rapid identification of microalgea to conventional methods based on genetic information and morphology. Thus, this efficient mass spectrometry-based technique may have applications in the rapid identification of harmful microorganisms from aquatic environmental samples. PMID:25476355

  8. Deriving Plasma Densities and Elemental Abundances from SERTS Differential Emission Measure Analysis

    NASA Technical Reports Server (NTRS)

    Schmelz, J. T.; Kimble, J. A.; Saba, J. L. R.

    2012-01-01

    We use high-resolution spectral emission line data obtained by the SERTS instrument during three rocket flights to demonstrate a new approach for constraining electron densities of solar active region plasma.We apply differential emission measure (DEM) forward-fitting techniques to characterize the multithermal solar plasma producing the observed EUV spectra, with constraints on the high-temperature plasma from the Yohkoh Soft X-ray Telescope. In this iterative process, we compare line intensities predicted by an input source distribution to observed line intensities for multiple iron ion species, and search a broad range of densities to optimize chi-square simultaneously for the many available density-sensitive lines. This produces a density weighted by the DEM, which appears to be useful for characterizing the bulk of the emitting plasma over a significant range of temperature. This "DEM-weighted density" technique is complementary to the use of density-sensitive line ratios and less affected by uncertainties in atomic data and ionization fraction for any specific line. Once the DEM shape and the DEM-weighted density have been established from the iron lines, the relative elemental abundances can be determined for other lines in the spectrum. We have also identified spectral lines in the SERTS wavelength range that may be problematic

  9. Space shuttle/food system study. Volume 2, Appendix G: Ground support system analysis. Appendix H: Galley functional details analysis

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The capabilities for preflight feeding of flight personnel and the supply and control of the space shuttle flight food system were investigated to determine ground support requirements; and the functional details of an onboard food system galley are shown in photographic mockups. The elements which were identified as necessary to the efficient accomplishment of ground support functions include the following: (1) administration; (2) dietetics; (3) analytical laboratories; (4) flight food warehouse; (5) stowage module assembly area; (6) launch site module storage area; (7) alert crew restaurant and disperse crew galleys; (8) ground food warehouse; (9) manufacturing facilities; (10) transport; and (11) computer support. Each element is discussed according to the design criteria of minimum cost, maximum flexibility, reliability, and efficiency consistent with space shuttle requirements. The galley mockup overview illustrates the initial operation configuration, food stowage locations, meal assembly and serving trays, meal preparation configuration, serving, trash management, and the logistics of handling and cleanup equipment.

  10. Spectroscopic survey of γ Doradus stars - I. Comprehensive atmospheric parameters and abundance analysis of γ Doradus stars

    NASA Astrophysics Data System (ADS)

    Kahraman Aliçavuş, F.; Niemczura, E.; De Cat, P.; Soydugan, E.; Kołaczkowski, Z.; Ostrowski, J.; Telting, J. H.; Uytterhoeven, K.; Poretti, E.; Rainer, M.; Suárez, J. C.; Mantegazza, L.; Kilmartin, P.; Pollard, K. R.

    2016-05-01

    We present a spectroscopic survey of known and candidate γ Doradus stars. The high-resolution, high signal-to-noise spectra of 52 objects were collected by five different spectrographs. The spectral classification, atmospheric parameters (Teff, log g, ξ), vsin i and chemical composition of the stars were derived. The stellar spectral and luminosity classes were found between G0-A7 and IV-V, respectively. The initial values for Teff and log g were determined from the photometric indices and spectral energy distribution. Those parameters were improved by the analysis of hydrogen lines. The final values of Teff, log g and ξ were derived from the iron lines analysis. The Teff values were found between 6000 K and 7900 K, while log g values range from 3.8 to 4.5 dex. Chemical abundances and vsin i values were derived by the spectrum synthesis method. The vsin i values were found between 5 and 240 km s-1. The chemical abundance pattern of γ Doradus stars were compared with the pattern of non-pulsating stars. It turned out that there is no significant difference in abundance patterns between these two groups. Additionally, the relations between the atmospheric parameters and the pulsation quantities were checked. A strong correlation between the vsin i and the pulsation periods of γ Doradus variables was obtained. The accurate positions of the analysed stars in the Hertzsprung-Russell diagram have been shown. Most of our objects are located inside or close to the blue edge of the theoretical instability strip of γ Doradus.

  11. Zinc Abundances in Galactic Bulge Stars

    NASA Astrophysics Data System (ADS)

    Silveira, C. R.; Barbuy, B.

    2014-10-01

    Zinc is overabundant in metal-poor stars (Cayrel et al. 2004), being partially produced by neutron addition. It decreases with increasing metallicity, similarly to alpha-elements. In order to trace its abundance, the derivation of Zn abundance in different stellar populations, and varying metallicities, helps understanding its nucleosynthesis processes. Zn is also the main element of reference to derive the metallicity from absorption lines in quasars (QSOs), which allows to compare their evolution as a function of redshift and metallicity in metal-poor stars. In the present work, we derive Zn abundances for a sample of 56 bulge field stars, observed at high resolution with the FLAMES-UVES spectrograph. The mean wavelength coverage is 4800-6800 Å, at a resolution R ˜ 45000. The atmospheric parameters effective temperature, gravity and metallicity were derived in Zoccali et al. (2008) and Hill et al. (2011). Recently we have analysed the manganese abundances of this sample (Barbuy et al. 2013). To compute the Zn abundances we use spectrum synthesis, for the lines ZnI 4810.53 and 6362.34 Å. The analysis of our data shows that the abundance of [Zn/Fe] decreases with increasing metallicity, in agreement with the data obtained from the literature. The details of Zn behaviour for the metal-rich bulge stars of the present work are under analysis.

  12. Abundances and implications of volatile-bearing species from evolved gas analysis of the Rocknest aeolian deposit, Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Archer, Paul Douglas; Franz, Heather B.; Sutter, Brad; Arevalo, Ricardo D.; Coll, Patrice; Eigenbrode, Jennifer L.; Glavin, Daniel P.; Jones, John J.; Leshin, Laurie A.; Mahaffy, Paul R.; McAdam, Amy C.; McKay, Christopher P.; Ming, Douglas W.; Morris, Richard V.; Navarro-González, Rafael; Niles, Paul B.; Pavlov, Alex; Squyres, Steven W.; Stern, Jennifer C.; Steele, Andrew; Wray, James J.

    2014-01-01

    The Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory (MSL) rover Curiosity detected evolved gases during thermal analysis of soil samples from the Rocknest aeolian deposit in Gale Crater. Major species detected (in order of decreasing molar abundance) were H2O, SO2, CO2, and O2, all at the µmol level, with HCl, H2S, NH3, NO, and HCN present at the tens to hundreds of nmol level. We compute weight % numbers for the major gases evolved by assuming a likely source and calculate abundances between 0.5 and 3 wt.%. The evolution of these gases implies the presence of both oxidized (perchlorates) and reduced (sulfides or H-bearing) species as well as minerals formed under alkaline (carbonates) and possibly acidic (sulfates) conditions. Possible source phases in the Rocknest material are hydrated amorphous material, minor clay minerals, and hydrated perchlorate salts (all potential H2O sources), carbonates (CO2), perchlorates (O2 and HCl), and potential N-bearing materials (e.g., Martian nitrates, terrestrial or Martian nitrogenated organics, ammonium salts) that evolve NH3, NO, and/or HCN. We conclude that Rocknest materials are a physical mixture in chemical disequilibrium, consistent with aeolian mixing, and that although weathering is not extensive, it may be ongoing even under current Martian surface conditions.

  13. A robust method for ammonium nitrogen isotopic analysis in freshwater and seawater at natural abundance levels

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Altabet, M. A.; Wu, T.; Hadas, O.

    2006-12-01

    Natural ammonium N isotopic abundance has been increasingly used in studies of marine and freshwater biogeochemistry. However, current methods are time-consuming, subject to interference from DON, and not reliable at low concentrations. Our new method for determining the δ15N of ammonium overcomes these difficulties by employing the oxidation of ammonium to nitrite followed by conversion of nitrite to nitrous oxide. In the first step, ammonium is quantitatively oxidized by hypobromite at pH~12. After the addition of sodium arsenite to consume excess hypobromite, yield is verified by colorimetric NO2-measurement using sulfanilamide and naphthyl ethylenediamine (NED). Nitrite is further reduced to N2O by a 1:1 sodium azide and acetic acid buffer solution using previously established procedures. Buffer concentration can be varied according to sample matrix to ensure that a reaction pH between 2 and 4 is reached. The product nitrous oxide is then isotopically analyzed using a continuous flow purge and cryogenic trap system coupled to an isotope ratio mass spectrometer. Reliable δ15N values (±0.31‰) are obtained over a concentration range of 0.5 μM to 20 μM using 20 ml volumes of either fresh or seawater samples. Reagent blanks are very low, about 0.05 μM. There is no interference from any of the nitrogen containing compounds tested except short chain aliphatic amino acid (i.e. glycine) which typically are not present at sufficiently high environmental concentrations to pose a problem.

  14. Sims Analysis of Water Abundance and Hydrogen Isotope in Lunar Highland Plagioclase

    NASA Technical Reports Server (NTRS)

    Hui, Hejiu; Guan, Yunbin; Chen, Yang; Peslier, Anne H.; Zhang, Youxue; Liu, Yang; Rossman, George R.; Eiler, John M.; Neal, Clive R.

    2015-01-01

    The detection of indigenous water in mare basaltic glass beads has challenged the view established since the Apollo era of a "dry" Moon. Since this discovery, measurements of water in lunar apatite, olivine-hosted melt inclusions, agglutinates, and nominally anhydrous minerals have confirmed that lunar igneous materials contain water, implying that some parts of lunar mantle may have as much water as Earth's upper mantle. The interpretation of hydrogen (H) isotopes in lunar samples, however, is controversial. The large variation of H isotope ratios in lunar apatite (delta Deuterium = -202 to +1010 per mille) has been taken as evidence that water in the lunar interior comes from the lunar mantle, solar wind protons, and/or comets. The very low deuterium/H ratios in lunar agglutinates indicate that solar wind protons have contributed to their hydrogen content. Conversely, H isotopes in lunar volcanic glass beads and olivine-hosted melt inclusions being similar to those of common terrestrial igneous rocks, suggest a common origin for water in both Earth and Moon. Lunar water could be inherited from carbonaceous chondrites, consistent with the model of late accretion of chondrite-type materials to the Moon as proposed by. One complication about the sources of lunar water, is that geologic processes (e.g., late accretion and magmatic degassing) may have modified the H isotope signatures of lunar materials. Recent FTIR analyses have shown that plagioclases in lunar ferroan anorthosite contain approximately 6 ppm H2O. So far, ferroan anorthosite is the only available lithology that is believed to be a primary product of the lunar magma ocean (LMO). A possible consequence is that the LMO could have contained up to approximately 320 ppm H2O. Here we examine the possible sources of water in the LMO through measurements of water abundances and H isotopes in plagioclase of two ferroan anorthosites and one troctolite from lunar highlands.

  15. Detailed Analysis of Temporal Features on Contrast Enhanced Ultrasound May Help Differentiate Intrahepatic Cholangiocarcinoma from Hepatocellular Carcinoma in Cirrhosis

    PubMed Central

    Li, Rui; Yuan, Meng-Xia; Ma, Kuan-sheng; Li, Xiao-Wu; Tang, Chun-Lin; Zhang, Xiao-Hang; Guo, De-Yu; Yan, Xiao-Chu

    2014-01-01

    Aim To verify if detailed analysis of temporal enhancement patterns on contrast enhanced ultrasound (CEUS) may help differentiate intrahepatic cholangiocarcinoma (ICC) from hepatocellular carcinoma (HCC) in cirrhosis. Methods Thirty three ICC and fifty HCC in cirrhosis were enrolled in this study. The contrast kinetics of ICC and HCC was analyzed and compared. Results Statistical analysis did not reveal significant difference between ICC and HCC in the time of contrast first appearance and arterial peak maximum time. ICC displayed much earlier washout than that of HCC (47.93±26.45 seconds vs 90.86±31.26 seconds) in the portal phase, and most ICC (87.9%) showed washout before 60 seconds than HCC (16.0%). Much more ICC (78.8%) revealed marked washout than HCC (12.0%) while most HCC (88.0%) showed mild washout or no washout in late part of the portal phase (90–120 seconds). Twenty six out of thirty three ICC (78.8%) demonstrated both early washout(<60seconds) and marked washout in late part of the portal phase, whereas, only six of fifty HCC (12.0%)showed these temporal enhancement features (p = 0.000).When both early washout and marked washout in the portal phase are taken as diagnostic criterion for ICC, the diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 78.8%,88.0%,81.3%,86.3%,and 84.3% respectively by CEUS. Conclusions Analysis of detailed temporal enhancement features on CEUS is helpful differentiate ICC from HCC in cirrhosis.If a nodule in cirrhotic liver displays hyper-enhancement in the arterial phase followed by early and marked washout in the portal phase, the nodule is highly suspicious of ICC rather than HCC. PMID:24874413

  16. Detailed Hydrodynamic and X-Ray Spectroscopic Analysis of a Laser-Produced Rapidly-Expanding Aluminum Plasma

    SciTech Connect

    Chambers, D M; Glenzer, S H; Hawreliak, J; Wolfrum, E; Gouveia, A; Lee, R W; Marjoribanks, R S; Renner, O; Sondhauss, P; Topping, S; Young, P E; Pinto, P A; Wark, J S

    2001-04-03

    We present a detailed analysis of K-shell emission from laser-produced rapidly-expanding aluminum plasmas. This work forms part of a series of experiments performed at the Vulcan laser facility of the Rutherford Appleton Laboratory, UK. 1-D planar expansion was obtained by over-illuminating Al-microdot targets supported on CH plastic foils. The small size of the Al-plasma ensured high spatial and frequency resolution of the spectra, obtained with a single crystal spectrometer, two vertical dispersion variant double crystal spectrometers, and a vertical dispersion variant Johann Spectrometer. The hydrodynamic properties of the plasma were measured independently by spatially and temporally resolved Thomson scattering, utilizing a 4{omega} probe beam. This enabled sub- and super- critical densities to be probed relative to the 1{omega} heater beams. The deduced plasma hydrodynamic conditions are compared with those generated from the 1-D hydro-code Medusa, and the significant differences found in the electron temperature discussed. Synthetic spectra generated from the detailed term collisional radiative non-LTE atomic physics code Fly are compared with the experimental spectra for the measured hydrodynamic parameters, and for those taken from Medusa. Excellent agreement is only found for both the H- and He-like Al series when careful account is taken of the temporal evolution of the electron temperature.

  17. A method for detailed analysis of the structure of mast cell secretory granules by negative contrast imaging

    PubMed Central

    Tanaka, Shotaro; Takakuwa, Yuichi

    2016-01-01

    Secretory granules (SGs) in mast cells contain various molecules that elicit allergy symptoms and are generally considered therapeutic targets. However, the biogenesis, maintenance, regulation, and recycling of these granules remain controversial, mainly due to the lack of suitable live-cell imaging methods. In this study, we applied negative contrast imaging with soluble green fluorescent protein (GFP) expressed in the cytoplasm as a method to validate structural information of mast cell SGs. We evaluated the accuracy of the method in detail, and we demonstrated that it can be used for quantitative analysis. Using this technique, secretory granules, the nucleus, mitochondria, and the cell body were visualized in individual RBL-2H3 mast cells without any influence. When combined with conventional multicolor fluorescence imaging, visualization of SG-associated proteins and SG–SG fusion was achieved. Moreover, 3D images were constructed based on this method, and detailed information on the number, size, and shape of individual SGs was obtained. We found that cell volume was correlated with SG number. In summary, the technique provides valuable and unique data, and will therefore advance SG research. PMID:26997316

  18. Abundance analysis, spectral variability, and search for the presence of a magnetic field in the typical PGa star HD 19400

    NASA Astrophysics Data System (ADS)

    Hubrig, S.; Castelli, F.; González, J. F.; Carroll, T. A.; Ilyin, I.; Schöller, M.; Drake, N. A.; Korhonen, H.; Briquet, M.

    2014-08-01

    The aim of this study is to carry out an abundance determination, to search for spectral variability and for the presence of a weak magnetic field in the typical PGa star HD 19400. High-resolution, high signal-to-noise High Accuracy Radial-velocity Planet Searcher (HARPS) spectropolarimetric observations of HD 19400 were obtained at three different epochs in 2011 and 2013. For the first time, we present abundances of various elements determined using an ATLAS12 model, including the abundances of a number of elements not analysed by previous studies, such as Ne I, Ga II, and Xe II. Several lines of As II are also present in the spectra of HD 19400. To study the variability, we compared the behaviour of the line profiles of various elements. We report on the first detection of anomalous shapes of line profiles belonging to Mn and Hg, and the variability of the line profiles belonging to the elements Hg, P, Mn, Fe, and Ga. We suggest that the variability of the line profiles of these elements is caused by their non-uniform surface distribution, similar to the presence of chemical spots detected in HgMn stars. The search for the presence of a magnetic field was carried out using the moment technique and the Singular Value Decomposition (SVD) method. Our measurements of the magnetic field with the moment technique using 22 Mn II lines indicate the potential existence of a weak variable longitudinal magnetic field on the first epoch. The SVD method applied to the Mn II lines indicates = -76 ± 25 G on the first epoch, and at the same epoch the SVD analysis of the observations using the Fe II lines shows = -91 ± 35 G. The calculated false alarm probability values, 0.008 and 0.003, respectively, are above the value 10-3, indicating no detection.

  19. Food webs in Mongolian grasslands: the analysis of 13C and 15N natural abundances.

    PubMed

    Kohzu, Ayato; Iwata, T; Kato, M; Nishikawa, J; Wada, Eitaro; Amartuvshin, N; Namkhaidorj, B; Fujita, N

    2009-09-01

    Overgrazing often lowers species richness and productivity of grassland communities. For Mongolian grassland ecosystems, a lack of detailed information about food-web structures makes it difficult to predict the effects of overgrazing on species diversity and community composition. We analysed the delta13C and delta15N signatures of herbaceous plants, arthropods (grouped by feeding habit), wild and domestic mammals, and humans in central Mongolia to understand the predominant food-web pathways in this grassland ecosystem. The delta13C and delta15N values of mammals showed little variation within species, but varied considerably with slope position for arthropods. The apparent isotopic discrimination between body tissue and hair of mammals was estimated as 2.0 per thousand for delta13C and 2.1 per thousand for delta15N, which was large enough to cause overestimation of the trophic level of mammals if not taken into account when using hair samples to measure isotopic enrichment. PMID:19507080

  20. Measurement of elastic 12C+alpha scattering: details of the experiment, analysis, and discussion of phase shifts

    SciTech Connect

    Couture, Aaron Joseph; Detwiler, Rebecca; Gorres, Joachim; Stech, Edward J; Ugalde, Claudio; Wiescher, Michael C F; Heil, Michael; Kappeler, Franz; Azuma, Richard E; Buchmann, Lothar

    2009-01-01

    Recent global analyses of {sup 12}C({alpha},{gamma}){sup 16}O have incorporated both elastic-scallering and {beta}-decay data in addition to direct measurements. In that context, it has been shown that an improvement in the available elastic-scallering data could help determine the contribution of the two subthreshold states, 6.92(2{sup +}) and 7.12(1{sup -}) MeV, and with excellent statistics could restrict resonance parameters above the threshold. To this end angular distributions of {sup 12}C({alpha}, {alpha}){sup 12}C in the {alpha}-energy range of 2.6-8.2 MeV, at angles from 24 to 166 have been measured at the University of Notre Dame using an array of 32 silicon detectors. Details of the experiment are reported. In the present analysis, the phase shifts have been determined from our previously reported R-matrix fit to these data. The uncertainties in the R-matrix phase shifts ({ell} = 0...6) are derived by a new Monte Carlo analysis technique as described in the article. We provide these phase shifts here for general use, in particular for the improved analysis and extrapolation of the {alpha} radiative capture to low energies.

  1. Understanding the structure of skill through a detailed analysis of Individuals' performance on the Space Fortress game.

    PubMed

    Towne, Tyler J; Boot, Walter R; Ericsson, K Anders

    2016-09-01

    In this paper we describe a novel approach to the study of individual differences in acquired skilled performance in complex laboratory tasks based on an extension of the methodology of the expert-performance approach (Ericsson & Smith, 1991) to shorter periods of training and practice. In contrast to more traditional approaches that study the average performance of groups of participants, we explored detailed behavioral changes for individual participants across their development on the Space Fortress game. We focused on dramatic individual differences in learning and skill acquisition at the individual level by analyzing the archival game data of several interesting players to uncover the specific structure of their acquired skill. Our analysis revealed that even after maximal values for game-generated subscores were reached, the most skilled participant's behaviors such as his flight path, missile firing, and mine handling continued to be refined and improved (Participant 17 from Boot et al., 2010). We contrasted this participant's behavior with the behavior of several other participants and found striking differences in the structure of their performance, which calls into question the appropriateness of averaging their data. For example, some participants engaged in different control strategies such as "world wrapping" or maintaining a finely-tuned circular flight path around the fortress (in contrast to Participant 17's angular flight path). In light of these differences, we raise fundamental questions about how skill acquisition for individual participants should be studied and described. Our data suggest that a detailed analysis of individuals' data is an essential step for generating a general theory of skill acquisition that explains improvement at the group and individual levels. PMID:27214790

  2. Distribution and Abundance of Phlebotominae, Vectors of Leishmaniasis, in Argentina: Spatial and Temporal Analysis at Different Scales

    PubMed Central

    Quintana, María Gabriela; Fernández, María Soledad; Salomón, Oscar Daniel

    2012-01-01

    The spatial-temporal analysis of the abundance of insects, vectors of tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL), was performed in Argentina using spatial-temporal increasing scales. In the microscale (microfocal), the effect of the primary vegetation-crop interface in vector abundance was observed, and also how the shelters, food sources, and other environmental characteristics contribute to habitat microheterogeneity and so to a microheterogeneous vector distribution. In the mesoscale (locality or epidemic focus), the results from different foci of TL (rural and periurban) and VL (urban) suggested a metapopulation structure determined partially by quantifiable habitat variables that could explain the increase of risk associated to an increase of vector-human contact due to climatic or anthropogenic changes. In the macroscale (regional), captures of vectors and records of human cases allowed the construction of risk maps and predictive models of vector distribution. In conclusion, in order to obtain valid results transferrable to control programs from spatial studies, special attention should be paid in order to assure the consistency between the spatial scales of the hypotheses, data, and analytical tools of each experimental or descriptive design. PMID:22315620

  3. Dynamic Nuclear Polarization NMR Enables the Analysis of Sn-Beta Zeolite Prepared with Natural Abundance 119Sn Precursors

    PubMed Central

    2015-01-01

    The catalytic activity of tin-containing zeolites, such as Sn-Beta, is critically dependent on the successful incorporation of the tin metal center into the zeolite framework. However, synchrotron-based techniques or solid-state nuclear magnetic resonance (ssNMR) of samples enriched with 119Sn isotopes are the only reliable methods to verify framework incorporation. This work demonstrates, for the first time, the use of dynamic nuclear polarization (DNP) NMR for characterizing zeolites containing ∼2 wt % of natural abundance Sn without the need for 119Sn isotopic enrichment. The biradicals TOTAPOL, bTbK, bCTbK, and SPIROPOL functioned effectively as polarizing sources, and the solvent enabled proper transfer of spin polarization from the radical’s unpaired electrons to the target nuclei. Using bCTbK led to an enhancement (ε) of 75, allowing the characterization of natural-abundance 119Sn-Beta with excellent signal-to-noise ratios in <24 h. Without DNP, no 119Sn resonances were detected after 10 days of continuous analysis. PMID:24697321

  4. OXYGEN ABUNDANCES IN CEPHEIDS

    SciTech Connect

    Luck, R. E.; Andrievsky, S. M.; Korotin, S. N.; Kovtyukh, V. V. E-mail: serkor@skyline.od.ua E-mail: scan@deneb1.odessa.ua

    2013-07-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  5. Estimating wetland vegetation abundance from Landsat-8 operational land imager imagery: a comparison between linear spectral mixture analysis and multinomial logit modeling methods

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Gong, Zhaoning; Zhao, Wenji; Pu, Ruiliang; Liu, Ke

    2016-01-01

    Mapping vegetation abundance by using remote sensing data is an efficient means for detecting changes of an eco-environment. With Landsat-8 operational land imager (OLI) imagery acquired on July 31, 2013, both linear spectral mixture analysis (LSMA) and multinomial logit model (MNLM) methods were applied to estimate and assess the vegetation abundance in the Wild Duck Lake Wetland in Beijing, China. To improve mapping vegetation abundance and increase the number of endmembers in spectral mixture analysis, normalized difference vegetation index was extracted from OLI imagery along with the seven reflective bands of OLI data for estimating the vegetation abundance. Five endmembers were selected, which include terrestrial plants, aquatic plants, bare soil, high albedo, and low albedo. The vegetation abundance mapping results from Landsat OLI data were finally evaluated by utilizing a WorldView-2 multispectral imagery. Similar spatial patterns of vegetation abundance produced by both fully constrained LSMA algorithm and MNLM methods were observed: higher vegetation abundance levels were distributed in agricultural and riparian areas while lower levels in urban/built-up areas. The experimental results also indicate that the MNLM model outperformed the LSMA algorithm with smaller root mean square error (0.0152 versus 0.0252) and higher coefficient of determination (0.7856 versus 0.7214) as the MNLM model could handle the nonlinear reflection phenomenon better than the LSMA with mixed pixels.

  6. Man-machine Integration Design and Analysis System (MIDAS) Task Loading Model (TLM) experimental and software detailed design report

    NASA Technical Reports Server (NTRS)

    Staveland, Lowell

    1994-01-01

    This is the experimental and software detailed design report for the prototype task loading model (TLM) developed as part of the man-machine integration design and analysis system (MIDAS), as implemented and tested in phase 6 of the Army-NASA Aircrew/Aircraft Integration (A3I) Program. The A3I program is an exploratory development effort to advance the capabilities and use of computational representations of human performance and behavior in the design, synthesis, and analysis of manned systems. The MIDAS TLM computationally models the demands designs impose on operators to aide engineers in the conceptual design of aircraft crewstations. This report describes TLM and the results of a series of experiments which were run this phase to test its capabilities as a predictive task demand modeling tool. Specifically, it includes discussions of: the inputs and outputs of TLM, the theories underlying it, the results of the test experiments, the use of the TLM as both stand alone tool and part of a complete human operator simulation, and a brief introduction to the TLM software design.

  7. Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations Reveals a Core and Variable Microbiota

    PubMed Central

    Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J.

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a “core” and a “variable” part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations (“core” yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations (“variable” yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency. PMID:24358116

  8. Quantitative assessment of hyperspectral imaging in detection of plasmonic nanoparticles: a modified contrast-detail analysis approach

    NASA Astrophysics Data System (ADS)

    Wang, Jianting; Chen, Yu; Pfefer, T. Joshua

    2016-03-01

    Hyperspectral reflectance imaging (HRI) is an emerging imaging modality being applied for clinical indications such as tissue oximetry, and cancer detection based on endogenous biological constituents including plasmonic nanoparticles. However, there is currently a lack of standardized test methods for objective, quantitative evaluation of HRI system performance. Contrast-detail analysis (CDA) is a phantom-based test method commonly used to evaluate medical imaging devices (e.g., mammography systems) in terms of their lower detection limit. We investigated a modified CDA (mCDA) method to quantify the detectability of gold nanoparticles by HRI systems. Silicone-based turbid phantoms containing micro-fluidic channels were developed for the mCDA tests. Polydimethylsiloxane (PDMS) phantom materials were doped with chromophores and scatterers to achieve biologically relevant optical properties (OPs). Molds were used to produce cylindrical channels of diameters 0.3 to 1.65 mm and depths of 0.2 mm inside the phantoms. Channels were filled with a mixture of hemoglobin and concentrations of gold nanorods (GNR) and measured with our HRI system. The contrast of GNRs was solved with a spectral unmixing algorithm from the reflectance spectra. The lowest detectable concentration was determined as a function of inclusion size and depth and plotted as modified contrast detail curve (mCDC). mCDCs were used to compare the detectabilities of the HRI system with different data processing algorithms. It is demonstrated that our mCDA test method involving turbid microchannel phantoms can help to elucidate the combined performance of imaging devices and plasmonic nanoparticle contrast agents. This approach may be useful for performing clinical trial standardization and device re-calibration, thus ensuring quality control and clinical performance.

  9. Evaluating Best Practices in Raman Spectral Analysis for Uranium Speciation and Relative Abundance in Aqueous Solutions.

    PubMed

    Lu, Grace; Forbes, Tori Z; Haes, Amanda J

    2016-01-01

    Raman spectroscopy is emerging as a powerful tool for identifying hexavalent uranium speciation in situ; however, there is no straightforward protocol for identifying uranyl species in solution. Herein, uranyl samples are evaluated using Raman spectroscopy, and speciation is monitored at various solution pH values and anion compositions. Spectral quality is evaluated using two Raman excitation wavelengths (532 and 785 nm) as these are critical for maximizing signal-to-noise and minimizing background from fluorescent uranyl species. The Raman vibrational frequency of uranyl shifts according to the identity of the coordinating ions within the equatorial plane and/or solution pH; therefore, spectral barcode analysis and rigorous peak fitting methods are developed that allow accurate and routine uranium species identification. All in all, this user's guide is expected to provide a user-friendly, straightforward approach for uranium species identification using Raman spectroscopy. PMID:26607279

  10. Anarchy in the UK: Detailed genetic analysis of worker reproduction in a naturally occurring British anarchistic honeybee, Apis mellifera, colony using DNA microsatellites.

    PubMed

    Châline, N; Ratnieks, F L W; Burke, T

    2002-09-01

    Anarchistic behaviour is a very rare phenotype of honeybee colonies. In an anarchistic colony, many workers' sons are reared in the presence of the queen. Anarchy has previously been described in only two Australian colonies. Here we report on a first detailed genetic analysis of a British anarchistic colony. Male pupae were present in great abundance above the queen excluder, which was clearly indicative of extensive worker reproduction and is the hallmark of anarchy. Seventeen microsatellite loci were used to analyse these male pupae, allowing us to address whether all the males were indeed workers' sons, and how many worker patrilines and individual workers produced them. In the sample, 95 of 96 of the males were definitely workers' sons. Given that approximately 1% of workers' sons were genetically indistinguishable from queen's sons, this suggests that workers do not move any queen-laid eggs between the part of the colony where the queen is present to the area above the queen excluder which the queen cannot enter. The colony had 16 patrilines, with an effective number of patrilines of 9.85. The 75 males that could be assigned with certainty to a patriline came from 7 patrilines, with an effective number of 4.21. They were the offspring of at least 19 workers. This is in contrast to the two previously studied Australian naturally occurring anarchist colonies, in which most of the workers' sons were offspring of one patriline. The high number of patrilines producing males leads to a low mean relatedness between laying workers and males of the colony. We discuss the importance of studying such colonies in the understanding of worker policing and its evolution. PMID:12207729

  11. Adsorption and interaction energy of π ethene on Pt(1 1 1) and Pt alloys: A detailed analysis of vibrational, energetic and electronic properties

    NASA Astrophysics Data System (ADS)

    Haubrich, J.; Becker, C.; Wandelt, K.

    2009-06-01

    We present a detailed analysis of the electronic and geometric bonding properties of the model alkene ethene on different mono- and bimetallic surfaces to establish the difference between adsorption energy and interaction energy and to elucidate the chemical character of a single platinum atom in different chemical environments. The adsorption of ethene on Pt(1 1 1) at 100 K leads to two adsorption states, which are commonly described as being of di- σ-type (bidentate, μ 2η 2) and π-type (monodentate, μ 1η 2). While the later is the minority species on Pt(1 1 1) it is of larger abundance on the platinum alloys. We have chosen π-bonded ethene for our study since it can be found on Pt(1 1 1), the Pt 3Sn and Pt 2Sn surface alloys, and Cu 3Pt(1 1 1). Density functional theory calculations of the adsorption structures, site and decomposed densities of states, as well as partial charge densities in conjunction with vibrational spectroscopy show that the bonding, i.e. the interaction energy, of the π ethene is only weakly influenced by alloying. Even in a copper matrix - as in the case of Cu 3Pt(1 1 1) - the bonding platinum atom essentially keeps its chemical identity and the interaction energy is reduced by only 14% compared to Pt(1 1 1). This observation suggests that bonding on surfaces is a strongly localized phenomenon. However, the adsorption energy decreases significantly due to alloying, which is attributed to the varying local relaxation of the different metal surfaces.

  12. A model for determining when an analysis contains sufficient detail to provide adequate NEPA coverage for a proposed action

    SciTech Connect

    Eccleston, C.H.

    1994-11-01

    Neither the National Environmental Policy Act (NEPA) nor its subsequent regulations provide substantive guidance for determining the Level of detail, discussion, and analysis that is sufficient to adequately cover a proposed action. Yet, decisionmakers are routinely confronted with the problem of making such determinations. Experience has shown that no two decisionmakers are Likely to completely agree on the amount of discussion that is sufficient to adequately cover a proposed action. one decisionmaker may determine that a certain Level of analysis is adequate, while another may conclude the exact opposite. Achieving a consensus within the agency and among the public can be problematic. Lacking definitive guidance, decisionmakers and critics alike may point to a universe of potential factors as the basis for defending their claim that an action is or is not adequately covered. Experience indicates that assertions are often based on ambiguous opinions that can be neither proved nor disproved. Lack of definitive guidance slows the decisionmaking process and can result in project delays. Furthermore, it can also Lead to inconsistencies in decisionmaking, inappropriate Levels of NEPA documentation, and increased risk of a project being challenged for inadequate coverage. A more systematic and less subjective approach for making such determinations is obviously needed. A paradigm for reducing the degree of subjectivity inherent in such decisions is presented in the following paper. The model is specifically designed to expedite the decisionmaking process by providing a systematic approach for making these determination. In many cases, agencies may find that using this model can reduce the analysis and size of NEPA documents.

  13. Source apportionment of atmospheric PAHs in the Western Balkans by natural abundance radiocarbon analysis

    SciTech Connect

    Zdenek Zencak; Jana Klanova; Ivan Holoubek; Oerjan Gustafsson

    2007-06-01

    Progress in source apportionment of priority combustion-derived atmospheric pollutants can be made by an inverse approach to inventory emissions, namely, receptor-based compound class-specific radiocarbon analysis (CCSRA) of target pollutants. In the present study, CCSRA of the combustion-derived polycyclic aromatic hydrocarbons (PAHs) present in the atmosphere of the countries of the former republic of Yugoslavia was performed. The carbon stable isotope composition ({delta}{sup 13}C) of PAHs varied between -27.68 and -27.19{per_thousand}, whereas {Delta}{sup 14}C values ranged from -568{per_thousand} for PAHs sampled in Kosovo to -288{per_thousand} for PAHs sampled in the Sarajevo area. The application of an isotopic mass balance model to these {Delta}{sup 14}C data revealed a significant contribution (35-65%) from the combustion of non-fossil material to the atmospheric PAH pollution, even in urban and industrialized areas. Furthermore, consistency was observed between the isotopic composition of PAHs obtained by high-volume sampling and those collected by passive sampling. This encourages the use of passive samplers for CCSRA applications. This marks the first time that a CCSRA investigation could be executed on a geographically wide scale, providing a quantitative field-based source apportionment, which points out that also non-fossil combustion processes should be targeted for remedial action. 36 refs., 1 fig., 3 tabs.

  14. Improved statistical analysis of low abundance phenomena in bimodal bacterial populations.

    PubMed

    Reinhard, Friedrich; van der Meer, Jan Roelof

    2013-01-01

    Accurate detection of subpopulation size determinations in bimodal populations remains problematic yet it represents a powerful way by which cellular heterogeneity under different environmental conditions can be compared. So far, most studies have relied on qualitative descriptions of population distribution patterns, on population-independent descriptors, or on arbitrary placement of thresholds distinguishing biological ON from OFF states. We found that all these methods fall short of accurately describing small population sizes in bimodal populations. Here we propose a simple, statistics-based method for the analysis of small subpopulation sizes for use in the free software environment R and test this method on real as well as simulated data. Four so-called population splitting methods were designed with different algorithms that can estimate subpopulation sizes from bimodal populations. All four methods proved more precise than previously used methods when analyzing subpopulation sizes of transfer competent cells arising in populations of the bacterium Pseudomonas knackmussii B13. The methods' resolving powers were further explored by bootstrapping and simulations. Two of the methods were not severely limited by the proportions of subpopulations they could estimate correctly, but the two others only allowed accurate subpopulation quantification when this amounted to less than 25% of the total population. In contrast, only one method was still sufficiently accurate with subpopulations smaller than 1% of the total population. This study proposes a number of rational approximations to quantifying small subpopulations and offers an easy-to-use protocol for their implementation in the open source statistical software environment R. PMID:24205184

  15. The influence of photochemical fractionation on the evolution of the nitrogen isotope ratios - detailed analysis of current photochemical loss rates

    NASA Astrophysics Data System (ADS)

    Mandt, K. E.; Waite, J. H., Jr.; Westlake, J.; Magee, B.; Liang, M. C.; Bell, J.

    2012-04-01

    Tracking the evolution of molecular nitrogen over geologic time scales requires an understanding of the loss rates of both isotopologues (14N2 and 14N15N) as a function of time (e.g. Mandt et al., 2009). The relative loss rates, if different, “fractionate” the isotopes so that the ratios change as a function of time, and rate at which the ratio changes due to a loss process is determined by the “fractionation factor.” Photochemistry is known to fractionate the nitrogen isotopes in Titan’s atmosphere by preferentially removing the heavy isotope from the molecular nitrogen inventory and increasing the ratio (heavy/light) in one of the primary photochemical products, HCN. This fractionation occurs due to a selective shielding during photodissociation where the photons that dissociate 14N15N penetrate deeper into the atmosphere (Liang et al., 2007) than the photons that dissociate 14N14N. Two methods can be used to determine the photochemical fractionation factor, f. The first approach for calculating f is based on the isotopic ratios of the photochemical source and product, as measured by the Huygens Gas Chromatograph Mass Spectrometer (GCMS) (Niemann et al., 2010) and the Cassini Infrared Spectrometer (CIRS) (Vinatier et al., 2007), respectively. The second method uses the loss rates and the ratio of the source and requires detailed photochemical modeling to ensure that the loss rates are calculated accurately. We compare these two methods for calculating the photochemical fractionation factor for N2 by using measurements of the isotopic ratios of N2 and HCN combined with an updated coupled ion-neutral-thermal model (De la Haye et al., 2008). We find that accurate magnetospheric electron fluxes and a rotating model that accounts for diurnal variations are essential for accurate calculations of the HCN densities and for determination of the fractionation factor through photochemical modeling. References: De La Haye, V., J. H. Waite, Jr., T. E. Cravens, I. P

  16. Capella: Structure and Abundances

    NASA Technical Reports Server (NTRS)

    Brickhouse, Nancy S.

    1999-01-01

    This grant covers the analysis of ASCA spectra of the cool star binary system Capella. This project has also required the analysis of simultaneous EUVE data. The ASCA spectrum of Capella could not be fit with standard models; by imposing models based on strong lines observed with EUVE, a problem wavelength region was identified. Correcting the problem required calculations of atomic collision strengths of higher principal quantum number than had ever been calculated, resulting in a paper in process by Liedahl and Brickhouse. With these new models applied to the ASCA spectrum, better fits were obtained. While solar abundance ratios are generally consistent with the ASCA data, the ratio of Ne/Fe is three to four times lower than solar photospheric values. Whether there is a general First Ionization Potential (FIP) effect or a specific neon anomaly cannot be determined from these data. Detailed discussion has been provided to NASA in the most recent annual report (1997). Two poster presentations have been made regarding modeling requirements. A substantial paper is in the final revision form, following review by six co-authors. The results of this work have wide implications, since the newly calculated emission lines almost certainly contribute to other problems in fitting not only other stellar spectra, but also composite supernova remnants, galaxies, and cooling flow clusters of galaxies. Furthermore, Liedahl and Brickhouse have identified other species for which lines of a similar nature (high principal quantum number) will contribute significant flux. For moderate resolution X-ray spectra, lines left out of the models in relatively isolated bands, will be attributed to continuum flux by spectral fitting engines, causing errors in line-to-continuum ratios. Thus addressing the general theoretical problem is of crucial importance.

  17. Synthesis and detailed kinetic analysis of Sr4Al14O25:Eu2+ phosphor under black light irradiation

    NASA Astrophysics Data System (ADS)

    Sharma, Suchinder K.; Pitale, Shreyas S.; Malik, M. M.; Dubey, R. N.; Qureshi, M. S.

    Black light source (360 nm) is used to undertake detailed kinetic analysis of strontium aluminate (Sr4Al14O25:Eu2+) with a long-lasting afterglow. Thermally stimulated luminescence studies were carried out to obtain different trapping parameters such as order of kinetics, frequency factor(s) and activation energy (E). The non-shifting Tm property in the measured glow curves is used to describe the order of kinetics. Decay studies are also used to verify the order of kinetics. Double peak structure is obtained with peaks at 487 and 423 K. Glow curve deconvolution function using a computerized package is applied to find the associated trapping parameters. McKeever's Tm-Tstop method is applied to determine the trap distribution and to approximate energies. The depth of the traps is found to be varying within 0.50 and 1.36 eV. Photoluminescence studies reveal the emission characteristics and mechanism. The emission peak is obtained at 487 nm.

  18. Characterization of a bio-oil from pyrolysis of rice husk by detailed compositional analysis and structural investigation of lignin.

    PubMed

    Lu, Yao; Wei, Xian-Yong; Cao, Jing-Pei; Li, Peng; Liu, Fang-Jing; Zhao, Yun-Peng; Fan, Xing; Zhao, Wei; Rong, Liang-Ce; Wei, Yan-Bin; Wang, Shou-Ze; Zhou, Jun; Zong, Zhi-Min

    2012-07-01

    Detailed compositional analysis of a bio-oil (BO) from pyrolysis of rice husk was carried out. The BO was extracted sequentially with n-hexane, CCl(4), CS(2), benzene and CH(2)Cl(2). In total, 167 organic species were identified with GC/MS in the extracts and classified into alkanes, alcohols, hydroxybenzenes, alkoxybenzenes, dioxolanes, aldehydes, ketones, carboxylic acids, esters, nitrogen-containing organic compounds and other species. The benzene ring-containing species (BRCCs) were attributed to the degradation of lignin while most of the rests were derived from the degradation of cellulose and hemicellulose. Along with guaiacyl and p-hydroxyphenyl units as the main components, a new type of linkage was suggested, i.e., C(ar)-CH(2)-C(ar) in 4,4'-methylenebis(2,6-dimethoxyphenol). Based on the species identified, a possible macromolecular structure of the lignin and the mechanism for its pyrolysis are proposed. The BO was also extracted with petroleum ether in ca. 17.8% of the extract yield and about 82.1% of the extracted components are BRCCs. PMID:22609664

  19. Detailed Analysis of (−)-Palmyrolide A and Some Synthetic Derivatives as Voltage-Gated Sodium Channel Antagonists

    PubMed Central

    2015-01-01

    A small library of synthetic (−)-palmyrolide A diastereomers, analogues, and acyclic precursors have been examined with respect to their interaction with voltage-gated sodium channels (VGSCs). Toward this goal, the ability of (−)-palmyrolide A and analogues to antagonize veratridine-stimulated Na+ influx in primary cultures of mouse cerebrocortical neurons was assessed. We found that synthetic (−)-palmyrolide A and its enantiomer functioned as VGSC antagonists to block veratridine-induced sodium influx. A detailed NMR and computational analysis of four diastereomers revealed that none had the same combination of shape and electrostatic potential as exhibited by natural (−)-palmyrolide A. These data indicate that the relative configuration about the tert-butyl and methyl substituents appears to be a prerequisite for biological function. Additional testing revealed that the enamide double bond was not necessary for blocking veratridine-induced sodium influx, whereas the acyclic analogues and other macrolide diastereomers tested were inactive as inhibitors of VGSCs, suggesting that the intact macrolide was required. PMID:25343669

  20. Use of a Hierarchical Oligonucleotide Primer Extension Approach for Multiplexed Relative Abundance Analysis of Methanogens in Anaerobic Digestion Systems

    PubMed Central

    Chuang, Hui-Ping; Hsu, Mao-Hsuan; Chen, Wei-Yu

    2013-01-01

    In this study, we established a rapid multiplex method to detect the relative abundances of amplified 16S rRNA genes from known cultivatable methanogens at hierarchical specificities in anaerobic digestion systems treating industrial wastewater and sewage sludge. The method was based on the hierarchical oligonucleotide primer extension (HOPE) technique and combined with a set of 27 primers designed to target the total archaeal populations and methanogens from 22 genera within 4 taxonomic orders. After optimization for their specificities and detection sensitivity under the conditions of multiple single-nucleotide primer extension reactions, the HOPE approach was applied to analyze the methanogens in 19 consortium samples from 7 anaerobic treatment systems (i.e., 513 reactions). Among the samples, the methanogen populations detected with order-level primers accounted for >77.2% of the PCR-amplified 16S rRNA genes detected using an Archaea-specific primer. The archaeal communities typically consisted of 2 to 7 known methanogen genera within the Methanobacteriales, Methanomicrobiales, and Methanosarcinales and displayed population dynamic and spatial distributions in anaerobic reactor operations. Principal component analysis of the HOPE data further showed that the methanogen communities could be clustered into 3 distinctive groups, in accordance with the distribution of the Methanosaeta, Methanolinea, and Methanomethylovorans, respectively. This finding suggested that in addition to acetotrophic and hydrogenotrophic methanogens, the methylotrophic methanogens might play a key role in the anaerobic treatment of industrial wastewater. Overall, the results demonstrated that the HOPE approach is a specific, rapid, and multiplexing platform to determine the relative abundances of targeted methanogens in PCR-amplified 16S rRNA gene products. PMID:24077716

  1. Identification of Biodegradation Pathways in a Multi-Process Phytoremediation System (MPPS) Using Natural Abundance 14C Analysis of PLFA

    NASA Astrophysics Data System (ADS)

    Cowie, B. R.; Greenberg, B. M.; Slater, G. F.

    2008-12-01

    Optimizing remediation of petroleum-contaminated soils requires thorough understanding of the mechanisms and pathways involved in a proposed remediation system. In many engineered and natural attenuation systems, multiple degradation pathways may contribute to observed contaminant mass losses. In this study, biodegradation in the soil microbial community was identified as a major pathway for petroleum hydrocarbon removal in a Multi-Process Phytoremediation System (MPPS) using natural abundance 14C analysis of Phospholipid Fatty Acids (PLFA). In contaminated soils, PLFA were depleted in Δ14C to less than -800‰, directly demonstrating microbial uptake and utilization of petroleum derived carbon (Δ14C = -992‰) during bioremediation. Mass balance indicated that more than 80% of microbial carbon was derived from petroleum hydrocarbons and a maximum of 20% was produced from metabolism of modern carbon sources. In contrast, in a nearby uncontaminated control soil, the microbial community maintained a nearly modern 14C signature, suggesting preferential degradation of more labile, recent carbon. Mass balance using δ13C and Δ14C of soil CO2 demonstrated that mineralization of petroleum carbon contributed 60-65% of soil CO2 at the contaminated site. The remainder was derived from atmospheric (27-30%) and decomposition of non- petroleum natural organic carbon (5-10%). The clean control exhibited substantially lower CO2 concentrations that were derived from atmospheric (55%) and natural organic carbon (45%) sources. This study highlights the value of using multiple carbon isotopes to identify degradation pathways in petroleum- contaminated soils undergoing phytoremediation and the power of natural abundance 14C to detect petroleum metabolism in natural microbial communities.

  2. Genome-wide survey and analysis of microsatellites in the Pacific oyster genome: abundance, distribution, and potential for marker development

    NASA Astrophysics Data System (ADS)

    Wang, Jiafeng; Qi, Haigang; Li, Li; Zhang, Guofan

    2014-01-01

    Microsatellites are a ubiquitous component of the eukaryote genome and constitute one of the most popular sources of molecular markers for genetic studies. However, no data are currently available regarding microsatellites across the entire genome in oysters, despite their importance to the aquaculture industry. We present the first genome-wide investigation of microsatellites in the Pacific oyster Crassostrea gigas by analysis of the complete genome, resequencing, and expression data. The Pacific oyster genome is rich in microsatellites. A total of 604 653 repeats were identified, in average of one locus per 815 base pairs (bp). A total of 12 836 genes had coding repeats, and 7 332 were expressed normally, including genes with a wide range of molecular functions. Compared with 20 different species of animals, microsatellites in the oyster genome typically exhibited 1) an intermediate overall frequency; 2) relatively uniform contents of (A)n and (C)n repeats and abundant long (C)n repeats (≥24 bp); 3) large average length of (AG)n repeats; and 4) scarcity of trinucleotide repeats. The microsatellite-flanking regions exhibited a high degree of polymorphism with a heterozygosity rate of around 2.0%, but there was no correlation between heterozygosity and microsatellite abundance. A total of 19 462 polymorphic microsatellites were discovered, and dinucleotide repeats were the most active, with over 26% of loci found to harbor allelic variations. In all, 7 451 loci with high potential for marker development were identified. Better knowledge of the microsatellites in the oyster genome will provide information for the future design of a wide range of molecular markers and contribute to further advancements in the field of oyster genetics, particularly for molecular-based selection and breeding.

  3. Biodegradation of cis-1,4-Polyisoprene Rubbers by Distinct Actinomycetes: Microbial Strategies and Detailed Surface Analysis

    PubMed Central

    Linos, Alexandros; Berekaa, Mahmoud M.; Reichelt, Rudolf; Keller, Ulrike; Schmitt, Jürgen; Flemming, Hans-Curt; Kroppenstedt, Reiner M.; Steinbüchel, Alexander

    2000-01-01

    Several actinomycetes isolated from nature were able to use both natural rubber (NR) and synthetic cis-1,4-polyisoprene rubber (IR) as a sole source of carbon. According to their degradation behavior, they were divided into two groups. Representatives of the first group grew only in direct contact to the rubber substrate and led to considerable disintegration of the material during cultivation. The second group consisted of weaker rubber decomposers that did not grow adhesively, as indicated by the formation of clear zones (translucent halos) around bacterial colonies after cultivation on NR dispersed in mineral agar. Taxonomic analysis of four selected strains based on 16S rRNA similarity examinations revealed two Gordonia sp. strains, VH2 and Kb2, and one Mycobacterium fortuitum strain, NF4, belonging to the first group as well as one Micromonospora aurantiaca strain, W2b, belonging to the second group. Schiff's reagent staining tests performed for each of the strains indicated colonization of the rubber surface, formation of a bacterial biofilm, and occurrence of compounds containing aldehyde groups during cultivation with NR latex gloves. Detailed analysis by means of scanning electron microscopy yielded further evidence for the two different microbial strategies and clarified the colonization efficiency. Thereby, strains VH2, Kb2, and NF4 directly adhered to and merged into the rubber material, while strain W2b produced mycelial corridors, especially on the surface of IR. Fourier transform infrared spectroscopy comprising the attenuated total reflectance technique was applied on NR latex gloves overgrown by cells of the Gordonia strains, which were the strongest rubber decomposers. Spectra demonstrated the decrease in number of cis-1,4 double bonds, the formation of carbonyl groups, and the change of the overall chemical environment, indicating that an oxidative attack at the double bond is the first metabolic step of the biodegradation process. PMID:10742254

  4. Detailed analysis of the Canary on-sky results at the WHT using Rayleigh laser guide stars

    NASA Astrophysics Data System (ADS)

    Martin, O.; Gendron, É.; Morris, T.; Basden, A.; Hubert, Z.; Gratadour, D.; Osborn, J.; Vidal, F.; Chemla, F.; Rousset, G.; Myers, R.

    2014-07-01

    CANARY is the multi-object adaptive optics (MOAO) on-sky demonstrator developed by Durham University and LESIA Observatoire de Paris, in the perspective of the E-ELT. Since 2013, CANARY has been operating with 3 off-axis NGS and 4 off-axis Rayleigh LGS and compensating for one on-axis NGS observed with a near IR camera and the Truth Sensor (TS) for diagnostic purpose. In this paper, we present the tomographic performance of CANARY during the runs in 2013. We propose a detailed analysis of the tomographic error leading to the establishment of the CANARY wave-front error budget. In particular we are able to evaluate the tomographic error for each altitude in the atmosphere for a given reconstructor by modelling a set of one-layer covariance matrices. This tool allows us to understand the tradeoffs to be made in the building of the tomographic reconstructor. We present two methods for the wavefront error budget computation. The DTI one uses input system parameters and open loop WFS slopes to estimate the error in a number of independent terms. The DMTS method directly uses the Truth Sensor measurements to estimate the error. We show a good agreement between the two approaches making us confident in our modelling of the instrument. We derive estimations of the Strehl ratio from the error variance and compare them to the recorded IR image Strehl ratio. We find a good agreement between the two, hence validating our wavefront error analysis. Finally we present an on-sky validation of the tomographic reconstruction using LGS based on GLAO and MOAO data. We also quantify the gain brought by the LGS, comparing results obtained in MOAO with 3 NGS and with or without LGS in the wavefront measurements.

  5. Genome analysis of Excretory/Secretory proteins in Taenia solium reveals their Abundance of Antigenic Regions (AAR).

    PubMed

    Gomez, Sandra; Adalid-Peralta, Laura; Palafox-Fonseca, Hector; Cantu-Robles, Vito Adrian; Soberón, Xavier; Sciutto, Edda; Fragoso, Gladis; Bobes, Raúl J; Laclette, Juan P; Yauner, Luis del Pozo; Ochoa-Leyva, Adrián

    2015-01-01

    Excretory/Secretory (ES) proteins play an important role in the host-parasite interactions. Experimental identification of ES proteins is time-consuming and expensive. Alternative bioinformatics approaches are cost-effective and can be used to prioritize the experimental analysis of therapeutic targets for parasitic diseases. Here we predicted and functionally annotated the ES proteins in T. solium genome using an integration of bioinformatics tools. Additionally, we developed a novel measurement to evaluate the potential antigenicity of T. solium secretome using sequence length and number of antigenic regions of ES proteins. This measurement was formalized as the Abundance of Antigenic Regions (AAR) value. AAR value for secretome showed a similar value to that obtained for a set of experimentally determined antigenic proteins and was different to the calculated value for the non-ES proteins of T. solium genome. Furthermore, we calculated the AAR values for known helminth secretomes and they were similar to that obtained for T. solium. The results reveal the utility of AAR value as a novel genomic measurement to evaluate the potential antigenicity of secretomes. This comprehensive analysis of T. solium secretome provides functional information for future experimental studies, including the identification of novel ES proteins of therapeutic, diagnosis and immunological interest. PMID:25989346

  6. Genome analysis of Excretory/Secretory proteins in Taenia solium reveals their Abundance of Antigenic Regions (AAR)

    PubMed Central

    Gomez, Sandra; Adalid-Peralta, Laura; Palafox-Fonseca, Hector; Cantu-Robles, Vito Adrian; Soberón, Xavier; Sciutto, Edda; Fragoso, Gladis; Bobes, Raúl J.; Laclette, Juan P.; Yauner, Luis del Pozo; Ochoa-Leyva, Adrián

    2015-01-01

    Excretory/Secretory (ES) proteins play an important role in the host-parasite interactions. Experimental identification of ES proteins is time-consuming and expensive. Alternative bioinformatics approaches are cost-effective and can be used to prioritize the experimental analysis of therapeutic targets for parasitic diseases. Here we predicted and functionally annotated the ES proteins in T. solium genome using an integration of bioinformatics tools. Additionally, we developed a novel measurement to evaluate the potential antigenicity of T. solium secretome using sequence length and number of antigenic regions of ES proteins. This measurement was formalized as the Abundance of Antigenic Regions (AAR) value. AAR value for secretome showed a similar value to that obtained for a set of experimentally determined antigenic proteins and was different to the calculated value for the non-ES proteins of T. solium genome. Furthermore, we calculated the AAR values for known helminth secretomes and they were similar to that obtained for T. solium. The results reveal the utility of AAR value as a novel genomic measurement to evaluate the potential antigenicity of secretomes. This comprehensive analysis of T. solium secretome provides functional information for future experimental studies, including the identification of novel ES proteins of therapeutic, diagnosis and immunological interest. PMID:25989346

  7. Abundance analysis of B, A and F dwarfs in the M6 open cluster: Spectrum synthesis method

    NASA Astrophysics Data System (ADS)

    Kiliçoğlu, T.; Monier, R.; Fossati, L.

    2012-12-01

    The chemical abundances of 10 stars in the M6 open cluster (˜100 Myr) were derived using spectrum synthesis. The stars were observed using the FLAMES/GIRAFFE spectrograph. We found star-to-star variations in abundances for A type stars. General enrichment of Si, Cr, and Y were obtained for the cluster.

  8. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients

    SciTech Connect

    Butler, Wayne M.; Stewart, Renee R.; Merrick, Gregory S.

    2009-03-15

    the harmonic mean and expressions of the generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  9. Low abundance materials at the mars pathfinder landing site: An investigation using spectral mixture analysis and related techniques

    USGS Publications Warehouse

    Bell, J.F., III; Farrand, W. H.; Johnson, J. R.; Morris, R.V.

    2002-01-01

    Recalibrated and geometrically registered multispectral images from the Imager for Mars Pathfinder (IMP) were analyzed using Spectral Mixture Analysis (SMA) and related techniques. SMA models a multispectral image scene as a linear combination of end-member spectra, and anomalous materials which do not fit the model are detected as model residuals. While most of the IMP data studied here are modeled generally well using "Bright Dust," "Gray Rock," and "Shade" image endmembers, additional anomalous materials were detected through careful analysis of root mean square (RMS) error images resulting from SMA. For example, analysis of SMA fraction and RMS images indicates spectral differences within a previously monolithologic Dark Soil class. A type of Dark Soil that has high fractional abundances in rock fraction images (Gray Rock Soil) was identified. Other anomalous materials identified included a previously noted "Black Rock" lithology, a class of possibly indurated, compacted, or partially cemented soils ("Intermediate Soil"), and a unit referred to as "Anomalous Patches" on at least one rock. The Black Rock lithology has a strong 900-1000-nm absorption, and modeling of the derived image endmembers using a laboratory reference endmember modeling (REM) approach produced best-fit model spectra that are most consistent with the presence of high-Ca pyroxenes and/or olivine, crystalline ferric oxide minerals, or mixtures of these materials as important components of the Black Rock endmember. More unique mineralogic identifications could not be obtained using our initial REM analyses. Both Intermediate Soil and Anomalous Patches units exhibit a relatively narrow 860-950-nm absorption that is consistent with the presence of either low-Ca pyroxenes or a cementing crystalline ferric oxide mineral. ?? 2002 Elsevier Science (USA).

  10. Abundances of Volatile - Bearing Species from Evolved Gas Analysis of Samples from the Rocknest Aeolian Bedform in Gale Crater

    NASA Technical Reports Server (NTRS)

    Archer, P. D., Jr.; Franc, H. B.; Sutter, B.; McAdam, A.; Ming, D. W.; Morris, R. V.; Mahaffy, P. R.

    2013-01-01

    The Sample Analysis at Mars (SAM) instrument suite on board the Mars Science Laboratory (MSL) recently ran four samples from an aeolian bedform named Rocknest. SAM detected the evolution of H2O, CO2, O2, and SO2, indicative of the presence of multiple volatile bearing species (Fig 1). The Rocknest bedform is a windblown deposit selected as representative of both the windblown material in Gale crater as well as the globally-distributed martian dust. Four samples of Rocknest material were analyzed by SAM, all from the fifth scoop taken at this location. The material delivered to SAM passed through a 150 m sieve and is assumed to have been well mixed during the sample acquisition/preparation/handoff process. SAM heated the Rocknest samples to approx.835 C at a ramp rate of 35 C/min with a He carrier gas flow rate of apprx.1.5 standard cubic centimeters per minute and at an oven pressure of 30 mbar [1]. Evolved gases were detected by a quadrupole mass spectrometer (QMS). This abstract presents the molar abundances of H2O, CO2, O2, and SO2 as well as their concentration in rocknest samples using an estimated sample mass.

  11. Glycan Degradation (GlyDeR) Analysis Predicts Mammalian Gut Microbiota Abundance and Host Diet-Specific Adaptations

    PubMed Central

    Zarecki, Raphy; Oberhardt, Matthew; Ursell, Luke K.; Kupiec, Martin; Knight, Rob; Gophna, Uri; Ruppin, Eytan

    2014-01-01

    ABSTRACT Glycans form the primary nutritional source for microbes in the human gut, and understanding their metabolism is a critical yet understudied aspect of microbiome research. Here, we present a novel computational pipeline for modeling glycan degradation (GlyDeR) which predicts the glycan degradation potency of 10,000 reference glycans based on either genomic or metagenomic data. We first validated GlyDeR by comparing degradation profiles for genomes in the Human Microbiome Project against KEGG reaction annotations. Next, we applied GlyDeR to the analysis of human and mammalian gut microbial communities, which revealed that the glycan degradation potential of a community is strongly linked to host diet and can be used to predict diet with higher accuracy than sequence data alone. Finally, we show that a microbe’s glycan degradation potential is significantly correlated (R = 0.46) with its abundance, with even higher correlations for potential pathogens such as the class Clostridia (R = 0.76). GlyDeR therefore represents an important tool for advancing our understanding of bacterial metabolism in the gut and for the future development of more effective prebiotics for microbial community manipulation. PMID:25118239

  12. Combined analysis of C-18 unsaturated fatty acids using natural abundance deuterium 2D NMR spectroscopy in chiral oriented solvents.

    PubMed

    Lesot, Philippe; Baillif, Vincent; Billault, Isabelle

    2008-04-15

    The quantitative determination of isotopic (2H/1H)i ratios at natural abundance using the SNIF-NMR protocol is a well-known method for understanding the enzymatic biosynthesis of metabolites. However, this approach is not always successful for analyzing large solutes and, specifically, is inadequate for prochiral molecules such as complete essential unsaturated fatty acids. To overcome these analytical limitations, we use the natural abundance deuterium 2D NMR (NAD 2D NMR) spectroscopy on solutes embedded in polypeptide chiral liquid crystals. This approach, recently explored for measuring (2H/1H)i ratios of small analytes (Lesot, P.; Aroulanda, C.; Billault, I. Anal. Chem. 2004, 76, 2827-2835), is a powerful way to separate the 2H signals of all nonequivalent enantioisotopomers on the basis both of the 2H quadrupolar interactions and of the 2H chemical shift. Two significant advances over our previous work are presented here and allow the complete isotopic analysis of four mono- and polyunsaturated fatty acid methyl esters: methyl oleate (1), methyl linoleate (2), methyl linolenate (3), and methyl vernoleate (4). The first consists of using NMR spectrometers operating at higher magnetic field strength (14.1 T) and equipped with a selective cryoprobe optimized for deuterium nuclei. The second is the development of Q-COSY Fz 2D NMR experiments able to produce phased 2H 2D maps after a double Fourier transformation. This combination of modern hardware and efficient NMR sequences provides a unique tool to analyze the (2H/1H)i ratios of large prochiral molecules (C-18) dissolved in organic solutions of poly(gamma-benzyl-L-glutamate) and requires smaller amounts of solute than previous study on fatty acids. For each compound (1-4), all 2H quadrupolar doublets visible in the 2D spectra have been assigned on the basis of 2H chemical shifts, isotopic data obtained from isotropic quantitative NAD NMR, and by an interspectral comparison of the anisotropic NAD spectra of four

  13. A novel method to prioritize RNAseq data for post-hoc analysis based on absolute changes in transcript abundance.

    PubMed

    McNutt, Patrick; Gut, Ian; Hubbard, Kyle; Beske, Phil

    2015-06-01

    The use of fold-change (FC) to prioritize differentially expressed genes (DEGs) for post-hoc characterization is a common technique in the analysis of RNA sequencing datasets. However, the use of FC can overlook certain population of DEGs, such as high copy number transcripts which undergo metabolically expensive changes in expression yet fail to exceed the ratiometric FC cut-off, thereby missing potential important biological information. Here we evaluate an alternative approach to prioritizing RNAseq data based on absolute changes in normalized transcript counts (ΔT) between control and treatment conditions. In five pairwise comparisons with a wide range of effect sizes, rank-ordering of DEGs based on the magnitude of ΔT produced a power curve-like distribution, in which 4.7-5.0% of transcripts were responsible for 36-50% of the cumulative change. Thus, differential gene expression is characterized by the high production-cost expression of a small number of genes (large ΔT genes), while the differential expression of the majority of genes involves a much smaller metabolic investment by the cell. To determine whether the large ΔT datasets are representative of coordinated changes in the transcriptional program, we evaluated large ΔT genes for enrichment of gene ontologies (GOs) and predicted protein interactions. In comparison to randomly selected DEGs, the large ΔT transcripts were significantly enriched for both GOs and predicted protein interactions. Furthermore, enrichments were were consistent with the biological context of each comparison yet distinct from those produced using equal-sized populations of large FC genes, indicating that the large ΔT genes represent an orthagonal transcriptional response. Finally, the composition of the large ΔT gene sets were unique to each pairwise comparison, indicating that they represent coherent and context-specific responses to biological conditions rather than the non-specific upregulation of a family of genes

  14. A comparative evaluation of rare-earth screen-film systems. System speed, contrast, sensitometry, RMS noise, square-wave response function, and contrast-dose-detail analysis.

    PubMed

    Fearon, T; Vucich, J; Hoe, J; McSweeney, W J; Potter, B M

    1986-08-01

    We evaluated the physical characteristics and contrast-dose-detail performance of 11 rare-earth and three calcium tungstate screen-film systems. Measurements included system speed, contrast, sensitometry, RMS noise, square-wave response function, and contrast-dose-detail analysis. The major differences in physical characteristics among systems were system speed and RMS noise. Square-wave response differences were more subtle. For contrast-dose-detail analysis, the rare-earth screen-film systems and the calcium tungstate system responses were significant over a limited subject contrast range as a function of detail diameter. Relative dose efficiency in the noise-limited region is a function of the properties of the screen only and is independent of the film. PMID:3744739

  15. NASA TLA workload analysis support. Volume 1: Detailed task scenarios for general aviation and metering and spacing studies

    NASA Technical Reports Server (NTRS)

    Sundstrom, J. L.

    1980-01-01

    The techniques required to produce and validate six detailed task timeline scenarios for crew workload studies are described. Specific emphasis is given to: general aviation single pilot instrument flight rules operations in a high density traffic area; fixed path metering and spacing operations; and comparative workload operation between the forward and aft-flight decks of the NASA terminal control vehicle. The validation efforts also provide a cursory examination of the resultant demand workload based on the operating procedures depicted in the detailed task scenarios.

  16. Carbon abundances of reference late-type stars from 1D analysis of atomic C I and molecular CH lines

    NASA Astrophysics Data System (ADS)

    Alexeeva, S. A.; Mashonkina, L. I.

    2015-10-01

    A comprehensive model atom was constructed for C I using the most up-to-date atomic data. We evaluated non-local thermodynamical equilibrium (NLTE) line formation for neutral carbon in classical one-dimensional (1D) models representing atmospheres of late-type stars, where carbon abundance varies from the solar value down to [C/H] = -3. NLTE leads to stronger C I lines compared with their local thermodynamical equilibrium (LTE) strength and negative NLTE abundance corrections, ΔNLTE. The deviations from LTE are large for the strong lines in the infrared (IR), with ΔNLTE = -0.10 to -0.45 dex, depending on stellar parameters, and minor for the weak lines in the visible spectral range, with |ΔNLTE| ≤ 0.03 dex. The NLTE abundance corrections were found to be dependent on the carbon abundance in the model. As the first application of the treated model atom, carbon NLTE abundances were determined for the Sun and eight late-type stars with well-determined stellar parameters that cover the -2.56 ≤ [Fe/H] ≤ -1.02 metallicity range. Consistent abundances from the visible and IR lines were found for the Sun and the most metal-rich star of our sample, when applying a scaling factor of SH = 0.3 to the Drawinian rates of C+H collisions. Carbon abundances were also derived from the molecular CH lines and agree with those from the atomic C I lines for each star. We present the NLTE abundance corrections for lines of C I in the grid of model atmospheres applicable to carbon-enhanced (CEMP) stars.

  17. MGA: A gamma-ray spectrum analysis code for determining plutonium isotopic abundances. Volume 3, FORTRAN listing of the GA code

    SciTech Connect

    Gunnink, R

    1991-09-01

    Nondestructive measurements of x-ray and gamma-ray emissions can be used to determine the abundances of various actinides in a sample. Volume 1 of this report describes the methods and algorithms we have developed to determine the relative isotopic abundances of actinides in a sample, by analyzing gamma-ray spectra obtained using germanium detector systems. Volume 2 is a guide to using the MGA (Multiple Group Analysis) computer program we have written to perform plutonium isotopic analyses. This report contains a listing of the FORTRAN instructions of the code.

  18. Proteomic Analysis of the Excretory-Secretory Products from Larval Stages of Ascaris suum Reveals High Abundance of Glycosyl Hydrolases

    PubMed Central

    Wang, Tao; Van Steendam, Katleen; Dhaenens, Maarten; Vlaminck, Johnny; Deforce, Dieter; Jex, Aaron R.; Gasser, Robin B.; Geldhof, Peter

    2013-01-01

    Background Ascaris lumbricoides and Ascaris suum are socioeconomically important and widespread parasites of humans and pigs, respectively. The excretory-secretory (ES) molecules produced and presented at the parasite-host interface during the different phases of tissue invasion and migration are likely to play critical roles in the induction and development of protective immune and other host responses. Methodology/Principal Findings The aim of this study was to identify the ES proteins of the different larval stages (L3-egg, L3-lung and L4) by LC-MS/MS. In total, 106 different proteins were identified, 20 in L3-egg, 45 in L3-lung stage and 58 in L4. Although most of the proteins identified were stage-specific, 15 were identified in the ES products of at least two stages. Two proteins, i.e. a 14-3-3-like protein and a serpin-like protein, were present in the ES products from the three different larval stages investigated. Interestingly, a comparison of ES products from L4 with those of L3-egg and L3-lung showed an abundance of metabolic enzymes, particularly glycosyl hydrolases. Further study indicated that most of these glycolytic enzymes were transcriptionally upregulated from L4 onwards, with a peak in the adult stage, particularly in intestinal tissue. This was also confirmed by enzymatic assays, showing the highest glycosidase activity in protein extracts from adult worms gut. Conclusions/Significance The present proteomic analysis provides important information on the host-parasite interaction and the biology of the migratory stages of A. suum. In particular, the high transcriptional upregulation of glycosyl hydrolases from the L4 stage onwards reveals that the degradation of complex carbohydrates forms an essential part of the energy metabolism of this parasite once it establishes in the small intestine. PMID:24098821

  19. SO and CS observations of molecular clouds. II. Analysis and modelling of the abundance ratios - probing O_2/CO with SO/CS?

    NASA Astrophysics Data System (ADS)

    Nilsson, A.; Hjalmarson, Å.; Bergman, P.; Millar, T. J.

    2000-06-01

    We here analyse the observational SO and CS data presented in Nilsson et al. (\\cite{2000A&A...XXX..XXXN}). The SO/CS integrated intensity ratio maps are presented for 19 molecular clouds, together with tables of relevant ratios at strategic positions, where we have also observed 34SO and/or C34S. The SO/CS abundance ratio as calculated from an LTE analysis is highly varying within and between the sources. Our isotopomer observations and Monte Carlo simulations verify that this is not an artifact due to optical depth problems. The variation of the maximum SO/CS abundance ratio between the clouds is 0.2-7. The largest variations within a cloud are found for the most nearby objects, possibly indicating resolution effects. We have also performed time dependent chemical simulations. We compare the simulations with our observed SO/CS abundance ratios and suggest a varying oxygen to carbon initial abundance, differing temporal evolution, density differences and X-ray sources associated with young stellar objects as possible explanations to the variations. In particular, the observed variation of the maximum SO/CS abundance ratio between the clouds can be explained by using initial O/C+ abundance ratios in the range 1.3-2.5. We finally derive a relationship between the SO/CS and O_2/CO abundance ratios, which may be used as a guide to find the most promising interstellar O_2 search targets. Table 1 and Figs. 4 to 21 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html)

  20. Analysis of High-Penetration Levels of Photovoltaics into the Distribution Grid on Oahu, Hawaii: Detailed Analysis of HECO Feeder WF1

    SciTech Connect

    Stewart, E.; MacPherson, J.; Vasilic, S.; Nakafuji, D.; Aukai, T.

    2013-05-01

    Renewable generation is growing at a rapid rate due to the incentives available and the aggressive renewable portfolio standard targets implemented by state governments. Distributed generation in particular is seeing the fastest growth among renewable energy projects, and is directly related to the incentives. Hawaii has the highest electricity costs in the country due to the high percentage of oil burning steam generation, and therefore has some of the highest penetration of distributed PV in the nation. The High Penetration PV project on Oahu aims to understand the effects of high penetration PV on the distribution level, to identify penetration levels creating disturbances on the circuit, and to offer mitigating solutions based on model results. Power flow models are validated using data collected from solar resources and load monitors deployed throughout the circuit. Existing interconnection methods and standards are evaluated in these emerging high penetration scenarios. A key finding is a shift in the level of detail to be considered and moving away from steady-state peak time analysis towards dynamic and time varying simulations. Each level of normal interconnection study is evaluated and enhanced to a new level of detail, allowing full understanding of each issue.

  1. An Abundance Analysis of Red Giant Stars in the Retrograde Galactic Globular Cluster NGC 3201: Implications for Cluster Formation Scenarios

    NASA Astrophysics Data System (ADS)

    Simmerer, Jennifer A.; Ivans, I. I.

    2011-01-01

    Globular clusters have long been central to the study of Galactic Chemical Evolution. They serve as laboratories for stellar physics, evolution, and nucleosynthesis as well as representing fossil remnants of Galactic assembly processes. Our work addresses two recent areas of interest: globular clusters as accreted objects and globular clusters as hosts for multiple stellar populations. The globular cluster NGC 3201 is a curious object on a retrograde orbit. Some studies suggest that it contains stars of more than one metallicity, a property seen only in the peculiar globular cluster Omega Centauri. Both properties hint at an extra-Galactic origin. We present an elemental abundance pattern for NGC 3201 based on high resolution, high signal-to-noise spectra of red giant stars. We present abundance patterns of similar stars from the globular cluster M5 for comparison. Interpretation of our results is complicated by the discovery that at least two of our giants are variable stars. Though we can derive adequate stellar parameter solutions for both stars in every stage of variability and heavy element abundances do not change with the stellar phase, the abundances of the light elements O, Na, Mg, and Al are extremely unstable and vary greatly. Our inability to correctly model light element line formation in the atmosphere of variable red giant stars has significant implications for studies of star to star abundance variations in exactly these elements in globular clusters, which rely on stars at the same evolutionary stage as the variables in NGC 3201.

  2. Prognosis of Ti abundance in Sinus Iridum using a nonlinear analysis of Chang' E-1 Interference Imaging Spectrometer imagery

    NASA Astrophysics Data System (ADS)

    Tingyan, Xing; Fujiang, Liu; Li, Liu; Chan, Li; Ying, Zhang; Le, Qiao; Rong, Yang; Xiaopo, Zheng; Meng, Zhu; Qi, Zhang

    2015-05-01

    We report here on the relationship between titanium abundance and its spectral features on the Moon, using 36 craters exposed in Sinus Iridum, a landing site for China's Lunar Exploration Program. Six absorption parameters (full width at half maximum, absorption depth (D), absorption position (λ), absorption area (A), absorption asymmetry (S), and (Rmin)) at the wavelength of 500-550 nm were computed, and the lowest reflectance values (Rmin) to characterize the properties of titanium abundance and its spectral features were calculated. The correlation between Rmin and TiO2 abundance calculated by Clementine multispectral images is 0.812, and a second-order polynomial fits the data better with a correlation of 0.837. The TiO2 abundance inversed by the Chang' E-1 Interference Imaging Spectrometers (IIM) data is thus relatively higher than that revealed by the Clementine data. This good correlation between Rmin and TiO2 abundance may thus be used very effectively to estimate the Ti distribution on the surface of the Moon by IIM hyperspectral data.

  3. Macroscale intraspecific variation and environmental heterogeneity: analysis of cold and warm zone abundance, mortality, and regeneration distributions of four eastern US tree species.

    PubMed

    Prasad, Anantha M

    2015-11-01

    I test for macroscale intraspecific variation of abundance, mortality, and regeneration of four eastern US tree species (Tsuga canadensis,Betula lenta,Liriodendron tulipifera, and Quercus prinus) by splitting them into three climatic zones based on plant hardiness zones (PHZs). The primary goals of the analysis are to assess the differences in environmental heterogeneity and demographic responses among climatic zones, map regional species groups based on decision tree rules, and evaluate univariate and multivariate patterns of species demography with respect to environmental variables. I use the Forest Inventory Analysis (FIA) data to derive abundance, mortality, and regeneration indices and split the range into three climatic zones based on USDA PHZs: (1) cold adapted, leading region; (2) middle, well-adapted region; and (3) warm adapted, trailing region. I employ decision tree ensemble methods to assess the importance of environmental predictors on the abundance of the species between the cold and warm zones and map zonal variations in species groups. Multivariate regression trees are used to simultaneously explore abundance, mortality, and regeneration in tandem to assess species vulnerability. Analyses point to the relative importance of climate in the warm adapted, trailing zone (especially moisture) compared to the cold adapted, leading zone. Higher mortality and lower regeneration patterns in the warm trailing zone point to its vulnerability to growing season temperature and precipitation changes that could figure more prominently in the future. This study highlights the need to account for intraspecific variation of demography in order to understand environmental heterogeneity and differential adaptation. It provides a methodology for assessing the vulnerability of tree species by delineating climatic zones based on easily available PHZ data, and FIA derived abundance, mortality, and regeneration indices as a proxy for overall growth and fitness. Based on

  4. Statistical analysis of polychaete population density: dynamics of dominant species and scaling properties in relative abundance fluctuations

    NASA Astrophysics Data System (ADS)

    Quiroz-Martinez, B.; Schmitt, F. G.; Dauvin, J.-C.

    2012-01-01

    We consider here the dynamics of two polychaete populations based on a 20 yr temporal benthic survey of two muddy fine sand communities in the Bay of Morlaix, Western English Channel. These populations display high temporal variability, which is analyzed here using scaling approaches. We find that population densities have heavy tailed probability density functions. We analyze the dynamics of relative species abundance in two different communities of polychaetes by estimating in a novel way a "mean square drift" coefficient which characterizes their fluctuations in relative abundance over time. We show the usefulness of using new tools to approach and model such highly variable population dynamics in marine ecosystems.

  5. Spatio-temporal analysis of abundances of three malaria vector species in southern Benin using zero-truncated models

    PubMed Central

    2014-01-01

    Background A better understanding of the ecology and spatial-temporal distribution of malaria vectors is essential to design more effective and sustainable strategies for malaria control and elimination. In a previous study, we analyzed presence-absence data of An. funestus, An. coluzzii, and An. gambiae s.s. in an area of southern Benin with high coverage of vector control measures. Here, we further extend the work by analysing the positive values of the dataset to assess the determinants of the abundance of these three vectors and to produce predictive maps of vector abundance. Methods Positive counts of the three vectors were assessed using negative-binomial zero-truncated (NBZT) mixed-effect models according to vector control measures and environmental covariates derived from field and remote sensing data. After 8-fold cross-validation of the models, predictive maps of abundance of the sympatric An. funestus, An. coluzzii, and An. gambiae s.s. were produced. Results Cross-validation of the NBZT models showed a satisfactory predictive accuracy. Almost all changes in abundance between two surveys in the same village were well predicted by the models but abundances for An. gambiae s.s. were slightly underestimated. During the dry season, predictive maps showed that abundance greater than 1 bite per person per night were observed only for An. funestus and An. coluzzii. During the rainy season, we observed both increase and decrease in abundance of An. funestus, which are dependent on the ecological setting. Abundances of both An. coluzzii and An. gambiae s.s. increased during the rainy season but not in the same areas. Conclusions Our models helped characterize the ecological preferences of three major African malaria vectors. This works highlighted the importance to study independently the binomial and the zero-truncated count processes when evaluating vector control strategies. The study of the bio-ecology of malaria vector species in time and space is critical

  6. The Economic Contribution of Canada's Colleges and Institutes. An Analysis of Investment Effectiveness and Economic Growth. Volume 2: Detailed Results by Gender and Entry Level of Education

    ERIC Educational Resources Information Center

    Robison, M. Henry; Christophersen, Kjell A.

    2008-01-01

    The purpose of this volume is to present the results of the economic impact analysis in detail by gender and entry level of education. On the data entry side, gender and entry level of education are important variables that help characterize the student body profile. This profile data links to national statistical databases which are already…

  7. Long-term Records of Pacific Salmon Abundance From Sediment Core Analysis: Relationships to Past Climatic Change, and Implications for the Future

    NASA Astrophysics Data System (ADS)

    Finney, B.

    2002-12-01

    The response of Pacific salmon to future climatic change is uncertain, but will have large impacts on the economy, culture and ecology of the North Pacific Rim. Relationships between sockeye salmon populations and climatic change can be determined by analyzing sediment cores from lakes where sockeye return to spawn. Sockeye salmon return to their natal lake system to spawn and subsequently die following 2 - 3 years of feeding in the North Pacific Ocean. Sockeye salmon abundance can be reconstructed from stable nitrogen isotope analysis of lake sediment cores as returning sockeye transport significant quantities of N, relatively enriched in N-15, from the ocean to freshwater systems. Temporal changes in the input of salmon-derived N, and hence salmon abundance, can be quantified through downcore analysis of N isotopes. Reconstructions of sockeye salmon abundance from lakes in several regions of Alaska show similar temporal patterns, with variability occurring on decadal to millennial timescales. Over the past 2000 years, shifts in sockeye salmon abundance far exceed the historical decadal-scale variability. A decline occurred from about 100 BC - 800 AD, but salmon were consistently more abundant 1200 - 1900 AD. Declines since 1900 AD coincide with the period of extensive commercial fishing. Correspondence between these records and paleoclimatic data suggest that changes in salmon abundance are related to large scale climatic changes over the North Pacific. For example, the increase in salmon abundance c.a. 1200 AD corresponds to a period of glacial advance in southern Alaska, and a shift to drier conditions in western North America. Although the regionally coherent patterns in reconstructed salmon abundance are consistent with the hypothesis that climate is an important driver, the relationships do not always follow patterns observed in the 20th century. A main feature of recorded climate variability in this region is the alternation between multi-decade periods of

  8. ANALYSIS OF TWO SMALL MAGELLANIC CLOUD H II REGIONS CONSIDERING THERMAL INHOMOGENEITIES: IMPLICATIONS FOR THE DETERMINATIONS OF EXTRAGALACTIC CHEMICAL ABUNDANCES

    SciTech Connect

    Pena-Guerrero, Maria A.; Peimbert, Antonio; Peimbert, Manuel; Ruiz, Maria Teresa E-mail: antonio@astroscu.unam.mx E-mail: mtruiz@das.uchile.cl

    2012-02-20

    We present long-slit spectrophotometry considering the presence of thermal inhomogeneities (t{sup 2}) of two H II regions in the Small Magellanic Cloud (SMC): NGC 456 and NGC 460. Physical conditions and chemical abundances were determined for three positions in NGC 456 and one position in NGC 460, first under the assumption of uniform temperature and then allowing for the possibility of thermal inhomogeneities. We determined t{sup 2} values based on three different methods: (1) by comparing the temperature derived using oxygen forbidden lines with the temperature derived using helium recombination lines (RLs), (2) by comparing the abundances derived from oxygen forbidden lines with those derived from oxygen RLs, and (3) by comparing the abundances derived from ultraviolet carbon forbidden lines with those derived from optical carbon RLs. The first two methods averaged t{sup 2} = 0.067 {+-} 0.013 for NGC 456 and t{sup 2} = 0.036 {+-} 0.027 for NGC 460. These values of t{sup 2} imply that when gaseous abundances are determined with collisionally excited lines they are underestimated by a factor of nearly two. From these objects and others in the literature, we find that in order to account for thermal inhomogeneities and dust depletion, the O/H ratio in low-metallicity H II regions should be corrected by 0.25-0.45 dex depending on the thermal structure of the nebula or by 0.35 dex if such information is not available.

  9. Elemental Abundances as a New Source of Uncertainty of the Hinode/XRT Filter-ratio T and EM Analysis

    NASA Astrophysics Data System (ADS)

    Takeda, A.; Kobelski, A.; McKenzie, D. E.; Yoshimura, K.

    2012-05-01

    We calculated the Hinode/XRT temperature response functions with different assumptions of elemental abundances. The enhancement of the low FIP elements significantly affects the amplitude of the XRT response curves. This yields a significant difference in the emission measures calculated from the filter ratio method, while the effect on derived temperatures is relatively small.

  10. Application of functional data analysis to investigate seasonal progression with interannual variability in plankton abundance in the Bay of Fundy, Canada

    NASA Astrophysics Data System (ADS)

    Ikeda, Takayoshi; Dowd, Michael; Martin, Jennifer L.

    2008-06-01

    The statistical technique of functional data analysis (FDA) is applied to a time series analysis of plankton monitoring data. The analysis is focused on revealing patterns in the seasonal cycle to assess interannual variability of several different taxonomic groups of plankton. Cell concentrations of diatom, dinoflagellate and zooplankton abundances from the Bay of Fundy, Canada provide the observations for analysis. FDA was performed on the log-transformed abundance data as a new approach for treating such types of sparse and noisy data. Differences in the seasonal progression were seen, with peak numbers, timings and abundance levels varying for the three groups as determined by curve registration and higher order derivatives using the objectively fit FDA curves. Nonmetric multidimensional scaling was used to capture seasonal variation among years. These results were further assessed in terms of dominant species and the relationships between groups for different seasons and years. It is anticipated that the easy to use, general and flexible technique of FDA could be applied to a wide variety of marine ecological data that are characterized by missing values and non-Gaussian distributions.

  11. Stellar Oxygen Abundances

    NASA Astrophysics Data System (ADS)

    King, Jeremy

    1994-04-01

    This dissertation addresses several issues concerning stellar oxygen abundances. The 7774 {\\AA} O I triplet equivalent widths of Abia & Rebolo [1989, AJ, 347, 186] for metal-poor dwarfs are found to be systematically too high. I also argue that current effective temperatures used in halo star abundance studies may be ~150 K too low. New color-Teff relations are derived for metal-poor stars. Using the revised Teff values and improved equivalent widths for the 7774A O I triplet, the mean [O/Fe] ratio for a handful of halo stars is found to be +0.52 with no dependence on Teff or [Fe/H]. Possible cosmological implications of the hotter Teff scale are discussed along with additional evidence supporting the need for a higher temperature scale for metal-poor stars. Our Teff scale leads to a Spite Li plateau value of N(Li)=2.28 +/- 0.09. A conservative minimal primordial value of N(Li)=2.35 is inferred. If errors in the observations and models are considered, consistency with standard models of Big Bang nucleosynthesis is still achieved with this larger Li abundance. The revised Teff scale raises the observed B/Be ratio of HD 140283 from 10 to 12, making its value more comfortably consistent with the production of the observed B and Be by ordinary spallation. Our Teff values are found to be in good agreement with values predicted from both the Victoria and Yale isochrone color-Teff relations. Thus, it appears likely that no changes in globular cluster ages would result. Next, we examine the location of the break in the [O/Fe] versus [Fe/H] plane in a quantitative fashion. Analysis of a relatively homogeneous data set does not favor any unique break point in the range -1.7 analysis also indicates that [O/Fe] is constant in the halo (at least for [Fe/H] >/= -3), in agreement with the new results for halo dwarfs. We find that the gap in the observed [O/H] distribution, noted by Wheeler et al

  12. Detailed Analysis of Temperature Characteristics of an InGaP/InGaAs/Ge Triple-Junction Solar Cell

    NASA Astrophysics Data System (ADS)

    Nishioka, Kensuke; Sueto, Tsuyoshi; Uchida, Masaki; Ota, Yasuyuki

    2010-06-01

    Temperature characteristics of an InGaP/InGaAs/Ge triple-junction solar cell were analyzed in detail using an equivalent circuit calculation. The current-voltage ( I- V) characteristics of single-junction solar cells (InGaP, InGaAs, Ge solar cells) were measured at various temperatures. Fitting of I- V curves between measured and calculated data was carried out, and the diode parameters and temperature exponents of the single-junction solar cells were extracted. The parameters for each single-junction solar cell were used in the equivalent circuit model for the triple-junction solar cell, and calculations of solar cell performance were carried out. Measured and calculated results of the I- V characteristics at various temperatures agreed well.

  13. Aortic Dissection Caused by Percutaneous Coronary Intervention: 2 New Case Reports and Detailed Analysis of 86 Previous Cases

    PubMed Central

    Bajaj, Sharad; Shamoon, Fayez

    2016-01-01

    Aortic dissection, a rare sequela of percutaneous coronary intervention, can be fatal when it is not recognized and treated promptly. Treatment varies from conservative management to invasive aortic repair and revascularization. We report the cases of 2 patients whose aortic dissection was caused by percutaneous coronary intervention. In addition, we present detailed analyses of 86 previously reported cases. Aortic dissection was most often seen during intervention to the right coronary artery (in 76.7% of instances). The 2 most frequently reported causes were catheter trauma (in 54% of cases) and balloon inflation (in 23.8%). The overall mortality rate was 7.1%. We conclude that most patients can be treated conservatively or by means of stenting alone, with no need for surgical intervention. PMID:27047287

  14. Analysis of a Detailed Genetic Linkage Map of Lactuca Sativa (Lettuce) Constructed from RFLP and Rapd Markers

    PubMed Central

    Kesseli, R. V.; Paran, I.; Michelmore, R. W.

    1994-01-01

    A detailed genetic map has been constructed from the F(2) population of a single intraspecific cross of Lactuca sativa (n = 9). It comprises 319 loci, including 152 restriction fragment length polymorphism (RFLP), 130 random amplified polymorphic DNA (RAPD), 7 isozyme, 19 disease resistance, and 11 morphological markers. Thirteen major, four minor linkage groups and several unlinked markers are identified for this genome which is estimated to be approximately 1950 cM. RFLP and RAPD markers show similar distributions throughout the genome and identified similar levels of polymorphism. RAPD loci were much quicker to identify but more difficult to order. Procedures for generating accurate genetic maps and their limitations are described. PMID:7912217

  15. Energy losing rate and open-circuit voltage analysis of organic solar cells based on detailed photocurrent simulation

    SciTech Connect

    Yu Junsheng; Huang Jiang; Zhang Lei; Jiang Yadong

    2009-09-15

    The J-V characteristics and photovoltaic response of indium tin oxide/pentacene (d nm)/C{sub 60} (40 nm)/BCP (10 nm)/Ag (100 nm) devices have been systematically analyzed. By fitting the J-V characteristics of the fabricated devices, photocurrent densities J{sub ph} were obtained. Meanwhile, we proposed a modified optical transfer matrix theory to satisfy the reasonable trend between P{sub 0}R{sub 0} and film thickness of pentacene layers. Then, we revealed that an accurate rate of energy loss can be defined as E{sub loss}=1-betaJ{sub e}/P{sub 0}R{sub 0}. Also, the relationship between open-circuit voltage V{sub OC}, compensation voltage V{sub 0} and initial polaron-pair bounding energy E{sub B} was determined based on the detailed study and simulation of device photocurrent.

  16. A new model for the aerobic metabolism of yeast allows the detailed analysis of the metabolic regulation during glucose pulse.

    PubMed

    Kesten, Duygu; Kummer, Ursula; Sahle, Sven; Hübner, Katrin

    2015-11-01

    The onset of aerobic fermentation (the so-called Crabtree effect) in yeast has long been of interest. However, the underlying mechanisms at the metabolic level are not yet fully understood. We developed a detailed kinetic model of the aerobic central metabolism of Saccharomyces cerevisiae comprising glycolysis, TCA cycle and major transport reactions across the mitochondrial membrane to investigate this phenomenon. It is the first one of this extent in the literature. The model is able to reproduce experimental steady state fluxes and time-course behavior after a glucose pulse. Due to the lack of parameter identifiability in the model, we analyze a model ensemble consisting of a set of differently parameterized models for robust findings. The model predicts that the cooperativity of pyruvate decarboxylase with respect to pyruvate and the capacity difference between alcohol dehydrogenase and the pyruvate dehydrogenase bypass play a major role for the onset of the Crabtree effect. PMID:26176974

  17. Quantifying mineral abundances of complex mixtures by coupling spectral deconvolution of SWIR spectra (2.1-2.4 μm) and regression tree analysis

    USGS Publications Warehouse

    Mulder, V.L.; Plotze, Michael; de Bruin, Sytze; Schaepman, Michael E.; Mavris, C.; Kokaly, Raymond F.; Egli, Markus

    2013-01-01

    This paper presents a methodology for assessing mineral abundances of mixtures having more than two constituents using absorption features in the 2.1-2.4 μm wavelength region. In the first step, the absorption behaviour of mineral mixtures is parameterised by exponential Gaussian optimisation. Next, mineral abundances are predicted by regression tree analysis using these parameters as inputs. The approach is demonstrated on a range of prepared samples with known abundances of kaolinite, dioctahedral mica, smectite, calcite and quartz and on a set of field samples from Morocco. The latter contained varying quantities of other minerals, some of which did not have diagnostic absorption features in the 2.1-2.4 μm region. Cross validation showed that the prepared samples of kaolinite, dioctahedral mica, smectite and calcite were predicted with a root mean square error (RMSE) less than 9 wt.%. For the field samples, the RMSE was less than 8 wt.% for calcite, dioctahedral mica and kaolinite abundances. Smectite could not be well predicted, which was attributed to spectral variation of the cations within the dioctahedral layered smectites. Substitution of part of the quartz by chlorite at the prediction phase hardly affected the accuracy of the predicted mineral content; this suggests that the method is robust in handling the omission of minerals during the training phase. The degree of expression of absorption components was different between the field sample and the laboratory mixtures. This demonstrates that the method should be calibrated and trained on local samples. Our method allows the simultaneous quantification of more than two minerals within a complex mixture and thereby enhances the perspectives of spectral analysis for mineral abundances.

  18. Aftershock mechanisms from the 2010 Mw 8.8 Maule, Chile earthquake: detailed analysis using full waveform inversion

    NASA Astrophysics Data System (ADS)

    Rietbrock, A.; Hicks, S. P.; Chagas, B.; Detzel, H. A.

    2014-12-01

    Since the earthquake rupture process is extremely heterogeneous, it is vital to understand how structural variations in the overriding plate and downgoing slab may control slip style along the subduction megathrust. The large-scale 3-D geometry of subduction plate boundaries is rapidly becoming well understood; however, the nature of any finer-scale structure along the plate interface remains elusive. A detailed study of earthquake source mechanisms along a megathrust region can shed light on the nature of fine-scale structures along the megathrust. The Mw 8.8 Maule earthquake that struck central Chile in 2010 is the sixth largest earthquake ever recorded. Following the earthquake, there was an international deployment of seismic stations in the rupture area, making this one of the best datasets of an aftershock sequence following a large earthquake. This dataset provides a unique opportunity to perform a detailed study of megathrust earthquake source mechanisms. Based on a high-resolution 3-D velocity model and robust earthquake locations [Hicks et al., 2014], we calculate regional moment tensors using the ISOLA software package [Sokos & Zahradnik, 2008]. We incorporate accelerometer recordings, important for constraining solutions of large earthquakes in the overriding plate. We also validate the robustness of our solutions by assessing the consistency of mechanisms with P-wave polarities observed at both onshore and offshore seismic stations, and compare them to already published solutions. We find that accurate earthquake locations are vital for the fine-scale interpretation of focal mechanisms, particularly for offshore events. Our results show that most moment tensor solutions with thrusting mechanisms have a nodal plane dipping parallel to the subducting plate interface. Interestingly, we also find earthquakes with normal faulting mechanisms lying along to the megathrust plate interface in the south of the rupture area. This finding suggests that megathrust

  19. Detailed Fracture System of the Soultz-sous-Forêts HDR Field Evaluated Using Microseismic Multiplet Analysis

    NASA Astrophysics Data System (ADS)

    Moriya, H.; Nakazato, K.; Niitsuma, H.; Baria, R.

    - The reservoir structure of the Soultz HDR field has been investigated by examining induced microearthquake multiplets. Microseismic events with similar waveforms have been selected from microseismic data obtained during a 1993 hydraulic fracturing experiment. Precise relative arrival times and source locations have been determined by cross-spectrum analysis. The cross-spectrum analysis decreased the residual from 0.75ms to 0.1ms. The estimated orientations of the multiplet planes are consistent with fracture orientations detected in Soultz boreholes. A comparison between the stress field and the orientation of structural planes suggests that the structural planes were under a critical condition of frictional slip.

  20. ABUNDANCES OF GALACTIC ANTICENTER PLANETARY NEBULAE AND THE OXYGEN ABUNDANCE GRADIENT IN THE GALACTIC DISK

    SciTech Connect

    Henry, R. B. C.; Morrison, Michael A.; Kwitter, Karen B.; Jaskot, Anne E.; Balick, Bruce; Milingo, Jacquelynne B. E-mail: morrison@nhn.ou.ed E-mail: ajaskot@umich.ed E-mail: jmilingo@gettysburg.ed

    2010-11-20

    We have obtained spectrophotometric observations of 41 anticenter planetary nebulae (PNe) located in the disk of the Milky Way. Electron temperatures and densities, as well as chemical abundances for He, N, O, Ne, S, Cl, and Ar were determined. Incorporating these results into our existing database of PN abundances yielded a sample of 124 well-observed objects with homogeneously determined abundances extending from 0.9 to 21 kpc in galactocentric distance. We performed a detailed regression analysis which accounted for uncertainties in both oxygen abundances and radial distances in order to establish the metallicity gradient across the disk to be 12 + log(O/H) = (9.09 {+-} 0.05) - (0.058 {+-} 0.006) x R{sub g} , with R{sub g} in kpc. While we see some evidence that the gradient steepens at large galactocentric distances, more objects toward the anticenter need to be observed in order to confidently establish the true form of the metallicity gradient. We find no compelling evidence that the gradient differs between Peimbert Types I and II, nor is oxygen abundance related to the vertical distance from the galactic plane. Our gradient agrees well with analogous results for H II regions but is steeper than the one recently published by Stanghellini and Haywood over a similar range in galactocentric distance. A second analysis using PN distances from a different source implied a flatter gradient, and we suggest that we have reached a confusion limit which can only be resolved with greatly improved distance measurements and an understanding of the natural scatter in oxygen abundances.

  1. CYCLoPs: A Comprehensive Database Constructed from Automated Analysis of Protein Abundance and Subcellular Localization Patterns in Saccharomyces cerevisiae

    PubMed Central

    Koh, Judice L. Y.; Chong, Yolanda T.; Friesen, Helena; Moses, Alan; Boone, Charles; Andrews, Brenda J.; Moffat, Jason

    2015-01-01

    Changes in protein subcellular localization and abundance are central to biological regulation in eukaryotic cells. Quantitative measures of protein dynamics in vivo are therefore highly useful for elucidating specific regulatory pathways. Using a combinatorial approach of yeast synthetic genetic array technology, high-content screening, and machine learning classifiers, we developed an automated platform to characterize protein localization and abundance patterns from images of log phase cells from the open-reading frame−green fluorescent protein collection in the budding yeast, Saccharomyces cerevisiae. For each protein, we produced quantitative profiles of localization scores for 16 subcellular compartments at single-cell resolution to trace proteome-wide relocalization in conditions over time. We generated a collection of ∼300,000 micrographs, comprising more than 20 million cells and ∼9 billion quantitative measurements. The images depict the localization and abundance dynamics of more than 4000 proteins under two chemical treatments and in a selected mutant background. Here, we describe CYCLoPs (Collection of Yeast Cells Localization Patterns), a web database resource that provides a central platform for housing and analyzing our yeast proteome dynamics datasets at the single cell level. CYCLoPs version 1.0 is available at http://cyclops.ccbr.utoronto.ca. CYCLoPs will provide a valuable resource for the yeast and eukaryotic cell biology communities and will be updated as new experiments become available. PMID:26048563

  2. Mobile Phones in a Traffic Flow: A Geographical Perspective to Evening Rush Hour Traffic Analysis Using Call Detail Records

    PubMed Central

    Järv, Olle; Ahas, Rein; Saluveer, Erki; Derudder, Ben; Witlox, Frank

    2012-01-01

    Excessive land use and suburbanisation around densely populated urban areas has gone hand in hand with a growth in overall transportation and discussions about causality of traffic congestions. The objective of this paper is to gain new insight regarding the composition of traffic flows, and to reveal how and to what extent suburbanites’ travelling affects rush hour traffic. We put forward an alternative methodological approach using call detail records of mobile phones to assess the composition of traffic flows during the evening rush hour in Tallinn, Estonia. We found that daily commuting and suburbanites influence transportation demand by amplifying the evening rush hour traffic, although daily commuting trips comprises only 31% of all movement at that time. The geography of the Friday evening rush hour is distinctive from other working days, presumably in connection with domestic tourism and leisure time activities. This suggests that the rise of the overall mobility of individuals due to societal changes may play a greater role in evening rush hour traffic conditions than does the impact of suburbanisation. PMID:23155461

  3. Details of Side Load Test Data and Analysis for a Truncated Ideal Contour Nozzle and a Parabolic Contour Nozzle

    NASA Technical Reports Server (NTRS)

    Ruf, Joseph H.; McDaniels, David M.; Brown, Andrew M.

    2010-01-01

    Two cold flow subscale nozzles were tested for side load characteristics during simulated nozzle start transients. The two test article contours were a truncated ideal and a parabolic. The current paper is an extension of a 2009 AIAA JPC paper on the test results for the same two nozzle test articles. The side load moments were measured with the strain tube approach in MSFC s Nozzle Test Facility. The processing techniques implemented to convert the strain gage signals into side load moment data are explained. Nozzle wall pressure profiles for separated nozzle flow at many NPRs are presented and discussed in detail. The effect of the test cell diffuser inlet on the parabolic nozzle s wall pressure profiles for separated flow is shown. The maximum measured side load moments for the two contours are compared. The truncated ideal contour s peak side load moment was 45% of that of the parabolic contour. The calculated side load moments, via mean-plus-three-standard-deviations at each nozzle pressure ratio, reproduced the characteristics and absolute values of measured maximums for both contours. The effect of facility vibration on the measured side load moments is quantified and the effect on uncertainty is calculated. The nozzle contour designs are discussed and the impact of a minor fabrication flaw in the nozzle contours is explained.

  4. Seismic evidence for an ancient rift beneath the cumberland plateau, Tennessee: A detailed analysis of broadband teleseismic P waveforms

    SciTech Connect

    Owens, T.J.; Zandt, G.; Taylor, S.R.

    1984-09-10

    Broadband receiver functions developed from teleseismic P waveforms recorded on the midperiod passband of Regional Seismic Test Network station RSCP are inverted for vertical velocity structure beneath the Cumberland Plateau, Tennessee. The detailed broadband receiver functions are obtained by stacking source-equalizd horizontal components of teleseismic P waveforms. The resulting receiver functions are most sensitive to the shear velocity structure near the station. A time domain inversion routine utilizes the radial receiver function to determine this structure assuming a crustal model parameterized by many thin, flat-lying, homogeneous layers. Lateral changes in structure are identified by examining azimuthal variations in the vertical structure. The results reveal significant rapid lateral changes in the midcrustal structure beneath the station that are interpreted in relation to the origin of the East Continent Gravity High located northeast of RSCP. The results from events arriving from the northeast show a high-velocity midcrustal layer not present in results from the southeast azimuth. This velocity structure can be shown to support the idea that this feature is part of a Keweenawan rift system. Another interesting feature of the derived velocity models is the indication that the crust-mantle boundary beneath the Cumberland Plateau is a thick, probably laminated transition zone between the depths of 40 and 55 km, a result consistent with interpretations of early refraction work in the area.

  5. A detailed analysis of cyclin A accumulation at the G(1)/S border in normal and transformed cells.

    PubMed

    Erlandsson, F; Linnman, C; Ekholm, S; Bengtsson, E; Zetterberg, A

    2000-08-25

    The temporal relationship between cyclin A accumulation and the onset of DNA replication was analyzed in detail. Five untransformed and nine transformed asynchronously growing cell cultures were investigated using a triple immunofluorescence staining protocol combined with computerized evaluation of staining intensities in individual cells. The simultaneous staining of BrdU, cyclin A, and cyclin E made it possible to determine the cell cycle position of each cell investigated. Cells at the G(1)/S border were identified on the basis of cyclin E content and were further analyzed with respect to cyclin A and BrdU content. A method was developed to calculate objective thresholds defining the highest staining intensity found in the negative cells in the population. Using the thresholds we could distinguish cells with minute amounts of cyclin A and BrdU from truly negative cells. We show that the onset of cyclin A accumulation and the start of DNA replication occurs at the same time, or deviating by a few minutes at the most. We also show that cyclin A accumulates continuously during S. This study clearly demonstrates that nuclear cyclin A can be used as a reliable marker for the S and G(2) phases in both normal and transformed interphase cells. PMID:10942581

  6. An Introductory Classroom Exercise on Protein Molecular Model Visualization and Detailed Analysis of Protein-Ligand Binding

    ERIC Educational Resources Information Center

    Poeylaut-Palena, Andres, A.; de los Angeles Laborde, Maria

    2013-01-01

    A learning module for molecular level analysis of protein structure and ligand/drug interaction through the visualization of X-ray diffraction is presented. Using DeepView as molecular model visualization software, students learn about the general concepts of protein structure. This Biochemistry classroom exercise is designed to be carried out by…

  7. Detailed Debunking of Denial

    NASA Astrophysics Data System (ADS)

    Enting, I. G.; Abraham, J. P.

    2012-12-01

    The disinformation campaign against climate science has been compared to a guerilla war whose tactics undermine the traditional checks and balances of science. One comprehensive approach has to been produce archives of generic responses such as the websites of RealClimate and SkepticalScience. We review our experiences with an alternative approach of detailed responses to a small number of high profile cases. Our particular examples were Professor Ian Plimer and Christopher Monckton, the Third Viscount Monckton of Brenchley, each of whom has been taken seriously by political leaders in our respective countries. We relate our experiences to comparable examples such as John Mashey's analysis of the Wegman report and the formal complaints about Lomborg's "Skeptical Environmentalist" and Durkin's "Great Global Warming Swindle". Our two approaches used contrasting approaches: an on-line video of a lecture vs an evolving compendium of misrepresentations. Additionally our approaches differed in the emphasis. The analysis of Monckton concentrated on the misrepresentation of the science, while the analysis of Plimer concentrated on departures from accepted scientific practice: fabrication of data, misrepresentation of cited sources and unattributed use of the work of others. Benefits of an evolving compendium were the ability to incorporate contributions from members of the public who had identified additional errors and the scope for addressing new aspects as they came to public attention. `Detailed debunking' gives non-specialists a reference point for distinguishing non-science when engaging in public debate.

  8. Elemental abundances of solar sibling candidates

    SciTech Connect

    Ramírez, I.; Lambert, D. L.; Endl, M.; Cochran, W. D.; MacQueen, P. J.; Bajkova, A. T.; Bobylev, V. V.; Wittenmyer, R. A.

    2014-06-01

    Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired high-resolution, high signal-to-noise ratio spectra for 30 of these objects to determine, using detailed elemental abundance analysis, if they could be true solar siblings. Only two of the candidates are found to have solar chemical composition. Updated modeling of the stars' past orbits in a realistic Galactic potential reveals that one of them, HD 162826, satisfies both chemical and dynamical conditions for being a sibling of the Sun. Measurements of rare-element abundances for this star further confirm its solar composition, with the only possible exception of Sm. Analysis of long-term high-precision radial velocity data rules out the presence of hot Jupiters and confirms that this star is not in a binary system. We find that chemical tagging does not necessarily benefit from studying as many elements as possible but instead from identifying and carefully measuring the abundances of those elements that show large star-to-star scatter at a given metallicity. Future searches employing data products from ongoing massive astrometric and spectroscopic surveys can be optimized by acknowledging this fact.

  9. Analysis of chemical abundances in planetary nebulae with [WC] central stars. I. Line intensities and physical conditions

    NASA Astrophysics Data System (ADS)

    García-Rojas, J.; Peña, M.; Morisset, C.; Mesa-Delgado, A.; Ruiz, M. T.

    2012-02-01

    Context. Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. Aims: We analyse deep high-resolution spectrophotometric data of 12 [WR] PNe. This sample of [WR]PNe represents the most extensive analysed so far, at such high spectral resolution. We aim to select the optimal physical conditions in the nebulae to be used in ionic abundance calculations that will be presented in a forthcoming paper. Methods: We acquired spectra at Las Campanas Observatory with the 6.5-m telescope and the Magellan Inamori Kyocera (MIKE) spectrograph, covering a wavelength range from 3350 Å to 9400 Å. The spectra were exposed deep enough to detect, with signal-to-noise ratio higher than three, the weak optical recombination lines (ORLs) of O ii, C ii, and other species. We detect and identify about 2980 emission lines, which, to date, is the most complete set of spectrophotometric data published for this type of objects. From our deep data, numerous diagnostic line ratios for Te and ne are determined from collisionally excited lines (CELs), ORLs, and continuum measurements (H i Paschen continuum in particular). Results: Densities are closely described by the average of all determined values for objects with ne < 104 cm-3, and by ne([Cl iii]) for the densest objects. For some objects, ne([Ar iv]) is adopted as the characteristic density of the high ionization zone. For Te, we adopt a three-zone ionization scheme, where the low ionization zone is characterised by Te([N ii]), the medium ionization zone by Te([O iii]), and the highest ionization one by Te([Ar iv]) when available. We compute Te from the H i Paschen discontinuity and from He i lines. For each object, Te(H i) is, in general, consistent with Te derived from CELs, although it has a very large error. Values of Te(He i) are systematically lower than the Te derived from CELs. When comparing Te(H i

  10. Using a detailed uncertainty analysis to adjust mapped rates of forest disturbance derived from Landsat time series data (Invited)

    NASA Astrophysics Data System (ADS)

    Cohen, W. B.; Yang, Z.; Stehman, S.; Huang, C.; Healey, S. P.

    2013-12-01

    Forest ecosystem process models require spatially and temporally detailed disturbance data to accurately predict fluxes of carbon or changes in biodiversity over time. A variety of new mapping algorithms using dense Landsat time series show great promise for providing disturbance characterizations at an annual time step. These algorithms provide unprecedented detail with respect to timing, magnitude, and duration of individual disturbance events, and causal agent. But all maps have error and disturbance maps in particular can have significant omission error because many disturbances are relatively subtle. Because disturbance, although ubiquitous, can be a relatively rare event spatially in any given year, omission errors can have a great impact on mapped rates. Using a high quality reference disturbance dataset, it is possible to not only characterize map errors but also to adjust mapped disturbance rates to provide unbiased rate estimates with confidence intervals. We present results from a national-level disturbance mapping project (the North American Forest Dynamics project) based on the Vegetation Change Tracker (VCT) with annual Landsat time series and uncertainty analyses that consist of three basic components: response design, statistical design, and analyses. The response design describes the reference data collection, in terms of the tool used (TimeSync), a formal description of interpretations, and the approach for data collection. The statistical design defines the selection of plot samples to be interpreted, whether stratification is used, and the sample size. Analyses involve derivation of standard agreement matrices between the map and the reference data, and use of inclusion probabilities and post-stratification to adjust mapped disturbance rates. Because for NAFD we use annual time series, both mapped and adjusted rates are provided at an annual time step from ~1985-present. Preliminary evaluations indicate that VCT captures most of the higher

  11. Detailed analysis of the effects of stencil spatial variations with arbitrary high-order finite-difference Maxwell solver

    NASA Astrophysics Data System (ADS)

    Vincenti, H.; Vay, J.-L.

    2016-03-01

    Very high order or pseudo-spectral Maxwell solvers are the method of choice to reduce discretization effects (e.g. numerical dispersion) that are inherent to low order Finite-Difference Time-Domain (FDTD) schemes. However, due to their large stencils, these solvers are often subject to truncation errors in many electromagnetic simulations. These truncation errors come from non-physical modifications of Maxwell's equations in space that may generate spurious signals affecting the overall accuracy of the simulation results. Such modifications for instance occur when Perfectly Matched Layers (PMLs) are used at simulation domain boundaries to simulate open media. Another example is the use of arbitrary order Maxwell solver with domain decomposition technique that may under some condition involve stencil truncations at subdomain boundaries, resulting in small spurious errors that do eventually build up. In each case, a careful evaluation of the characteristics and magnitude of the errors resulting from these approximations, and their impact at any frequency and angle, requires detailed analytical and numerical studies. To this end, we present a general analytical approach that enables the evaluation of numerical errors of fully three-dimensional arbitrary order finite-difference Maxwell solver, with arbitrary modification of the local stencil in the simulation domain. The analytical model is validated against simulations of domain decomposition technique and PMLs, when these are used with very high-order Maxwell solver, as well as in the infinite order limit of pseudo-spectral solvers. Results confirm that the new analytical approach enables exact predictions in each case. It also confirms that the domain decomposition technique can be used with very high-order Maxwell solvers and a reasonably low number of guard cells with negligible effects on the whole accuracy of the simulation.

  12. Detailed Anatomical Analysis of the Sphenoid Sinus and Sphenoid Sinus Ostium by Cone-Beam Computed Tomography.

    PubMed

    Yilmaz, Nesibe; Kose, Evren; Dedeoglu, Numan; Colak, Cemil; Ozbag, Davut; Durak, Mehmet Akif

    2016-09-01

    The aim of this study is the evaluation of the anatomical structures of sphenoid sinus ostium used as a reference point for transsphenoidal surgery by cone beam computed tomography. The authors' study was performed using the cone-beam computed tomography images of 16 to 82-year old 200 (112 female, 88 male) patients (Newton 5G, Verona, Italy). Septum deviation of sphenoid sinus and the distance between 2 ostia were evaluated by coronal and axial sections, respectively. Pneumatization degree of sphenoid sinus, diameter of sphenoid sinus ostium, and distance lower edge of superior turbinate to sphenoid sinus ostium were measured by using sagittal sections. The sellar type was the most common pneumatization type of sphenoid sinus in authors' study. While the C-type septum deviation was observed as the most common, T-type deviation was the least type. Sphenoid sinus ostium was bilaterally in 71.5% of individuals, and it was not found in 10% of individuals included in the study. A significant decrease was determined in diameter of the left sphenoid sinus ostium with aging. The distances between 2 sphenoid sinus ostia were 7.30 ± 2.77 mm for women and 6.09 ± 2.58 mm for men, respectively. No statistical differences were found in women and men in terms of distances between the lower edge of the right and left superior turbinate and sphenoid sinus ostium on their sides. Consequently, making detailed preoperative radiological evaluation of anatomic variations of sphenoid sinus and sphenoid sinus ostium is important in terms of guiding the surgeon in the process of a successful transsphenoidal surgery. PMID:27428910

  13. The Details of Glycolipid Glycan Hydrolysis by the Structural Analysis of a Family 123 Glycoside Hydrolase from Clostridium perfringens.

    PubMed

    Noach, Ilit; Pluvinage, Benjamin; Laurie, Cassandra; Abe, Kento T; Alteen, Matthew G; Vocadlo, David J; Boraston, Alisdair B

    2016-08-14

    Clostridium perfringens is an opportunistic pathogen of humans and animals whose genome encodes a wide variety of putative carbohydrate-hydrolyzing enzymes that are increasingly being shown to be directed toward the cleavage of host glycans. Among these putative enzymes is a member of glycoside hydrolase family 123. Here we show that the recombinant enzyme (referred to as CpNga123) encoded by the gene cloned from C. perfringens strain ATCC 13124 (locus tag CPF_1473) is a β-N-acetylgalactosaminidase, similar to NgaP from Paenibacillus sp. TS12. Like NgaP, CpNga123 was able to cleave the terminal β-D-GalNAc-(1→4)-D-Gal and β-D-GalNAc-(1→3)-D-Gal motifs that would be found in glycosphigolipids. The X-ray crystal structure of CpNga123 revealed it to have an N-terminal β-sandwich domain and a (β/α)8-barrel catalytic domain with a C-terminal α-helical elaboration. The structures determined in complex with reaction products provide details of the -1 subsite architecture, catalytic residues, and a structural change in the active site that is likely required to enable hydrolysis of the glycosidic bond by promoting engagement of the substrate by the catalytic residues. The features of the active site support the likelihood of a substrate-assisted catalytic mechanism for this enzyme. The structures of an inactive mutant of CpNga123 in complex with intact GA2 and Gb4 glycosphingolipid motifs reveal insight into aglycon recognition and suggest that the kinked or pleated conformation of GA2 caused by the β-1,4-linkage between N-acetylgalactosamine and galactose, and the accommodation of this conformation by the enzyme active site, may be responsible for greater activity on GA2. PMID:27038508

  14. Tectonic evolution of the eastern margin of the Thaumasia Plateau (Mars) as inferred from detailed structural mapping and analysis

    NASA Astrophysics Data System (ADS)

    Borraccini, F.; Di Achille, G.; Ori, G. G.; Wezel, F. C.

    2007-05-01

    The eastern margin of the Thaumasia Plateau (EMTP) is characterized by a diversity of tectonic features, which recorded its complex, and still controversial, tectonic history. A detailed structural survey and analyses have been carried out in order to assess the kinematics and relative age of the main deformational events. Combining results from statistics of lineament orientations and density of fault length for each geologic unit and taking into account crosscutting relationships among tectonic structures, three main deformational events have been recognized. The early stage of the tectonic evolution of EMTP is recorded by Noachian units at the southern edge of Melas Dorsa and is represented by N-S oriented grabens sutured by Early Hesperian formations. Starting from Late Noachian, the extensional stress field became NE-SW oriented and resulted in the formation of NW-SE striking sets of grabens. At the boundary between Noachian and Hesperian, the most important change in tectonic regime occurred. The Hesperian tectonics are characterized by an E-W shortening possibly related to an eastward motion of the Thaumasia Plateau. This tectonic phase likely produced a N-S-oriented wrinkle ridges as well as regional folds and thrust faults. E-W-oriented preexisting tectonic lineaments could have been reactivated forming regional transfer zones. In this scenario, Coprates Rise, Melas Dorsa, and Thaumasia Ridge could be interpreted as mountain belts resulting from buckling and thrust faulting of the eastern and southern margins of the Thaumasia plateau. The proto-Valles Marineris could have experienced a left-lateral component of displacement and played a role of a transfer shear zone.

  15. Detailed gene copy number and RNA expression analysis of the 17q12-23 region in primary breast cancers.

    PubMed

    Willis, Simon; Hutchins, Anne-Marie; Hammet, Fleur; Ciciulla, John; Soo, Wee-Kheng; White, David; van der Spek, Peter; Henderson, Michael A; Gish, Kurt; Venter, Deon J; Armes, Jane E

    2003-04-01

    Chromosome region 17q12-23 commonly shows an increase in DNA copy number in breast cancers, suggesting that several oncogenes are located at this site. We performed a high-resolution expression array and comparative genomic hybridization analysis of genes mapped to the entire 17q12-23 region, to identify novel candidate oncogenes. We identified 24 genes that showed significant overexpression in breast cancers with gain of 17q12-23, compared to cancers without gain. These genes included previously identified oncogenes, together with several novel candidate oncogenes. FISH analysis using specific gene probes hybridized to tissue arrays confirmed the underlying amplification of overexpressed genes. This high-resolution analysis of the 17q12-23 region indicates that several established and novel candidate oncogenes, including a Wnt-signaling pathway member, are amplified and overexpressed within individual primary breast cancer samples. We were also able to confirm the presence of two apparently separate and reciprocally amplified groups of genes within this region. Investigation of these genes and their functional interactions will facilitate our understanding of breast oncogenesis and optimal management of this disease. PMID:12619162

  16. Evaluation of lunar rocks and soils for resource utilization: Detailed image analysis of raw materials and beneficiated products

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence A.; Chambers, John G.; Patchen, Allan; Jerde, Eric A.; Mckay, David S.; Graf, John; Oder, Robin R.

    1993-01-01

    The rocks and soils of the Moon will be the raw materials for fuels and construction needs at a lunar base. This includes sources of materials for the generation of hydrogen, oxygen, metals, and other potential construction materials. For most of the bulk material needs, the regolith, and its less than 1 cm fraction, the soil, will suffice. But for specific mineral resources, it may be necessary to concentrate minerals from rocks or soils, and it is not always obvious which is the more appropriate feedstock. Besides an appreciation of site geology, the mineralogy and petrography of local rocks and soils is important for consideration of the resources which can provide feedstocks of ilmenite, glass, agglutinates, anorthite, etc. In such studies, it is very time-consuming and practically impossible to correlate particle counts (the traditional method of characterizing lunar soil petrography) with accurate modal analyses and with mineral associations in multi-mineralic grains. But x ray digital imaging, using x rays characteristic of each element, makes all this possible and much more (e.g., size and shape analysis). An application of beneficiation image analysis, in use in our lab (Oxford Instr. EDS and Cameca SX-50 EMP), was demonstrated to study mineral liberation from lunar rocks and soils. Results of x ray image analysis are presented.

  17. Integrated analysis of transcriptomic and proteomic data of Desulfovibrio vulgaris: Zero-Inflated Poisson regression models to predict abundance of undetected proteins

    SciTech Connect

    Nie, Lei; Wu, Gang; Brockman, Fred J.; Zhang, Weiwen

    2006-05-04

    Abstract Advances in DNA microarray and proteomics technologies have enabled high-throughput measurement of mRNA expression and protein abundance. Parallel profiling of mRNA and protein on a global scale and integrative analysis of these two data types could provide additional insight into the metabolic mechanisms underlying complex biological systems. However, because protein abundance and mRNA expression are affected by many cellular and physical processes, there have been conflicting results on the correlation of these two measurements. In addition, as current proteomic methods can detect only a small fraction of proteins present in cells, no correlation study of these two data types has been done thus far at the whole-genome level. In this study, we describe a novel data-driven statistical model to integrate whole-genome microarray and proteomic data collected from Desulfovibrio vulgaris grown under three different conditions. Based on the Poisson distribution pattern of proteomic data and the fact that a large number of proteins were undetected (excess zeros), Zero-inflated Poisson models were used to define the correlation pattern of mRNA and protein abundance. The models assumed that there is a probability mass at zero representing some of the undetected proteins because of technical limitations. The models thus use abundance measurements of transcripts and proteins experimentally detected as input to generate predictions of protein abundances as output for all genes in the genome. We demonstrated the statistical models by comparatively analyzing D. vulgaris grown on lactate-based versus formate-based media. The increased expressions of Ech hydrogenase and alcohol dehydrogenase (Adh)-periplasmic Fe-only hydrogenase (Hyd) pathway for ATP synthesis were predicted for D. vulgaris grown on formate.

  18. Abundance analysis of SDSS J134338.67+484426.6; an extremely metal-poor star from the MARVELS pre-survey

    NASA Astrophysics Data System (ADS)

    Susmitha Rani, A.; Sivarani, T.; Beers, T. C.; Fleming, S.; Mahadevan, S.; Ge, J.

    2016-05-01

    We present an elemental-abundance analysis of an extremely metal-poor (EMP; [Fe/H] <-3.0) star, SDSS J134338.67+484426.6, identified during the course of the Multi-object Apache Point Observatory Radial Velocity Exoplanet Large-area Survey spectroscopic pre-survey of some 20 000 stars to identify suitable candidates for exoplanet searches. This star, with an apparent magnitude V = 12.14, is the lowest metallicity star found in the pre-survey, and is one of only ˜20 known EMP stars that are this bright or brighter. Our high-resolution spectroscopic analysis shows that this star is a subgiant with [Fe/H] = -3.42, having `normal' carbon and no enhancement of neutron-capture abundances. Strontium is underabundant, [Sr/Fe] = -0.47, but the derived lower limit on [Sr/Ba] indicates that Sr is likely enhanced relative to Ba. This star belongs to the sparsely populated class of α-poor EMP stars that exhibit low ratios of [Mg/Fe], [Si/Fe], and [Ca/Fe] compared to typical halo stars at similar metallicity. The observed variations in radial velocity from several epochs of (low- and high-resolution) spectroscopic follow-up indicate that SDSS J134338.67+484426.6 is a possible long-period binary. We also discuss the abundance trends in EMP stars for r-process elements, and compare with other magnesium-poor stars.

  19. Detailed angular correlation analysis with 4{pi} spectrometers: Spin determinations and multipolarity mixing measurements in {sup 128}Ba

    SciTech Connect

    Wiedenhoever, I.; Vogel, O.; Klein, H.; Dewald, A.; von Brentano, P.; Gableske, J.; Nicolay, N.; Gelberg, A.; Wiedenhoever, I.; Janssens, R.V.; Carpenter, M.P.; Kruecken, R.; Petkov, P.; Gizon, A.; Gizon, J.; Bazzacco, D.; Rossi Alvarez, C.; Pavan, P.; de Angelis, G.; Lunardi, S.; Napoli, D.R.; Frauendorf, S.; Doenau, F.

    1998-08-01

    We analyze for the first time the full {gamma}{gamma} directional correlations from oriented states (DCO) in an experiment performed with the GASP detector array. Our analysis is based on a transformation of the directional information into expansion coefficients of an orthogonal basis. With this method, which we call SpeeDCO (spectral expansion of DCO), the complete DCO information is concentrated in 12 {gamma}{gamma} coincidence spectra. The analysis is applicable to all detector arrays which uniformly cover the solid angle. We show that the complete DCO information can be used for a reliable and unique determination of spins and multipolarity mixing ratios in weakly populated bands. We were able to establish the spins and the positive parity of the {Delta}I=1 {open_quotes}M1 band{close_quotes} in {sup 128}Ba and multipolarity mixing ratios of nine M1/E2 in-band transitions were derived as well. The measured values are in good agreement with those expected for a high-K rotational band. thinsp thinsp thinsp {copyright} {ital 1998} {ital The American Physical Society}

  20. Analyzing PACS Usage Patterns by Means of Process Mining: Steps Toward a More Detailed Workflow Analysis in Radiology.

    PubMed

    Forsberg, Daniel; Rosipko, Beverly; Sunshine, Jeffrey L

    2016-02-01

    In this paper, statistical analysis and techniques from process mining are employed to analyze interaction patterns originating from radiologists reading medical images in a picture archiving and communication system (PACS). Event logs from 1 week of data, corresponding to 567 cases of single-view chest radiographs read by 14 radiologists, were analyzed. Statistical analysis showed that the numbers of commands and command types used by the radiologists per case only have a slightly positive correlation with the time to read a case (0.31 and 0.55, respectively). Further, one way ANOVA showed that the factors time of day, radiologist and specialty were significant for the number of commands per case, whereas radiologist was also significant for the number of command types, but with no significance of any of the factors on time to read. Applying process mining to the event logs of all users showed that a seemingly "simple" examination (single-view chest radiographs) can be associated with a highly complex interaction process. However, repeating the process discovery on each individual radiologist revealed that the initially discovered complex interaction process consists of one group of radiologists with individually well-structured interaction processes and a second smaller group of users with progressively more complex usage patterns. Future research will focus on metrics to describe derived interaction processes in order to investigate if one set of interaction patterns can be considered as more efficient than another set when reading radiological images in a PACS. PMID:26353749

  1. The abundances of H-3 and C-14 in the solar wind. [measured by lunar soil analysis

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.; Defelice, J.; Damico, J.

    1976-01-01

    Tritium is measured as a function of depth in a Surveyor 3 sample. The upper limit for solar-wind-implanted tritium gives a H-3/H-1 limit for the solar wind of 1 part in one hundred billion. The temperature release patterns of C-14 from lunar soils are measured. The C-14 release patterns from surface soils differ from a trench-bottom soil and give evidence for the presence of C-14 in the solar wind with a C-14/H-1 ratio of approximately 4 parts in one hundred billion. The implications of these radionuclide abundances in the solar wind are discussed.

  2. Single-step analysis of low abundance phosphoamino acids via on-line sample preconcentration with chemical derivatization by capillary electrophoresis.

    PubMed

    Ptolemy, Adam S; Britz-McKibbin, Philip

    2005-09-01

    New strategies for rapid, sensitive and high-throughput analysis of low abundance metabolites in biological samples are required for future metabolomic research. In this report, a direct method for sub-micromolar analyses of phosphoamino acids was developed using on-line sample preconcentration with 9-fluorenylmethyloxycarbonyl chloride (FMOC) derivatization by capillary electrophoresis (CE) and UV detection. Analyte focusing by dynamic pH junction and FMOC labeling efficiency were influenced by several experimental factors including buffer pH, ionic strength, sample injection length and FMOC concentration. About a 200-fold enhancement in concentration sensitivity was achieved under optimal conditions relative to conventional off-line derivatization, as reflected by a detection limit (S/N approximately 3) of 0.1 microM. In-capillary sample preconcentration with chemical labeling by CE offers a unique single-step analytical platform for high-throughput screening of low abundance metabolites without intrinsic chromophores. PMID:16096672

  3. PSIDD (2): A Prototype Post-Scan Interactive Data Display System for Detailed Analysis of Ultrasonic Scans

    NASA Technical Reports Server (NTRS)

    Cao, Wei; Roth, Don J.

    1997-01-01

    This article presents the description of PSIDD(2), a post-scan interactive data display system for ultrasonic contact scan and single measurement analysis. PSIDD(2) was developed in conjunction with ASTM standards for ultrasonic velocity and attenuation coefficient contact measurements. This system has been upgraded from its original version PSIDD(1) and improvements are described in this article. PSIDD(2) implements a comparison mode where the display of time domain waveforms and ultrasonic properties versus frequency can be shown for up to five scan points on one plot. This allows the rapid contrasting of sample areas exhibiting different ultrasonic properties as initially indicated by the ultrasonic contact scan image. This improvement plus additional features to be described in the article greatly facilitate material microstructural appraisal.

  4. Detailed analysis of Honeywell In-Space Accelerometer data - STS-32. [crystal microstructure response to different types of residual acceleration

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.; Alexander, J. I. D.; Schoess, Jeff

    1993-01-01

    The Honeywell In-Space Accelerometer (HISA) system collected data in the mid-deck area of the Shuttle Columbia during the flight of STS-32, January 1990. The resulting data were to be used to investigate the response of crystal microstructure to different types of residual acceleration. The HISA is designed to detect and record transient and oscillatory accelerations. The sampling and electronics package stored averaged accelerations over two sampling periods; two sampling rates were available: 1 Hz and 50 Hz. Analysis of the HISA data followed the CMMR Acceleration Data Processing Guide, considering in-house computer modelling of a float-zone indium crystal growth experiment. Characteristic examples of HISA data showing the response to the primary reaction control system, Orbiter Maneuvering System operations, and crew treadmill activity are presented. Various orbiter structural modes are excited by these and other activities.

  5. Detailed numerical analysis of photon emission from a single light emitter coupled with a nanofiber Bragg cavity.

    PubMed

    Takashima, Hideaki; Fujiwara, Masazumi; Schell, Andreas W; Takeuchi, Shigeki

    2016-06-27

    Coupling of a single dipole with a nanofiber Bragg cavity (NFBC) approximating an actually fabricated structure was numerically analyzed using three dimensional finite-difference time-domain simulations for different dipole positions. For the given model structure, the Purcell factor and coupling efficiency reached to 19.1 and 82%, respectively, when the dipole is placed outside the surface of the fiber. Interestingly, these values are very close to the highest values of 20.2 and 84% obtained for the case when the dipole was located inside the fiber at the center. The analysis performed in this study will be useful in improving the performance of single-photon emitter-related quantum devices using NFBCs. PMID:27410656

  6. Detailed analysis of isotopic ratio of radioactive iodine in surface soil around Fukushima Daiichi Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    Miyake, Yasuto; Matsuzaki, Hiroyuki; Fujiwara, Takeshi; Saito, Takumi; Yamagata, Takeyasu; Honda, Maki

    2013-04-01

    In March 2011, there was an accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) and a lot of radionuclides were discharged into the environment, resulting from a powerful earthquake and tsunami. Considering the impact on human health, the radiation dosimetry is the most important for Iodine-131 among radionuclides in the initial stage immediately following the release of radionuclides. However, Iodine-131 cannot be detected after several months owing to its short half-life (8 days). Cesium-137 was also leaked out from the FDNPP and this can be detected now. But this did not identically act with Iodine-131 and be suitable for the reconstruction of Iodine-131 distribution at the initial stage. Since Iodine-129 (half-life: 1.57E7 yrs) can be detected in the future and it act chemically identically with Iodine-131, the reconstruction by Iodine-129 analysis is important. For this reconstruction, it is necessary to know the isotopic ratio of radioactive iodine (129I/131I) released from the FDNPP. In this study, the Iodine-129 concentration was measured by accelerator mass spectrometry (AMS) in several surface soil samples collected around the FDNPP for which the Iodine-131level had already been determined. Soil samples were put into a U8 standard vessel after being roughly homogenized and dried. Then, samples were homogenized again more completely and several grams were taken for Iodine-129 measurement. Each sample was combusted in a quartz tube and outgas was trapped in alkali solution. An aliquot was taken from the trap solution for the determination of the Iodine-127 concentration by inductively coupled plasma mass spectrometry (ICP-MS). The iodine carrier was added to the trap solution, from which the iodine fraction was purified by solvent extraction and back extraction. Finally, silver iodide precipitation was obtained by adding silver nitrate solution. After dried, the precipitation was mixed with niobium powder and pressed into a cathode for the target

  7. Deep sequencing analysis of viral infection and evolution allows rapid and detailed characterization of viral mutant spectrum

    PubMed Central

    Isakov, Ofer; Bordería, Antonio V.; Golan, David; Hamenahem, Amir; Celniker, Gershon; Yoffe, Liron; Blanc, Hervé; Vignuzzi, Marco; Shomron, Noam

    2015-01-01

    Motivation: The study of RNA virus populations is a challenging task. Each population of RNA virus is composed of a collection of different, yet related genomes often referred to as mutant spectra or quasispecies. Virologists using deep sequencing technologies face major obstacles when studying virus population dynamics, both experimentally and in natural settings due to the relatively high error rates of these technologies and the lack of high performance pipelines. In order to overcome these hurdles we developed a computational pipeline, termed ViVan (Viral Variance Analysis). ViVan is a complete pipeline facilitating the identification, characterization and comparison of sequence variance in deep sequenced virus populations. Results: Applying ViVan on deep sequenced data obtained from samples that were previously characterized by more classical approaches, we uncovered novel and potentially crucial aspects of virus populations. With our experimental work, we illustrate how ViVan can be used for studies ranging from the more practical, detection of resistant mutations and effects of antiviral treatments, to the more theoretical temporal characterization of the population in evolutionary studies. Availability and implementation: Freely available on the web at http://www.vivanbioinfo.org Contact: nshomron@post.tau.ac.il Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25701575

  8. Detailed analysis of association between common single nucleotide polymorphisms and subclinical atherosclerosis: The Multi-ethnic Study of Atherosclerosis.

    PubMed

    Vargas, Jose D; Manichaikul, Ani; Wang, Xin-Qun; Rich, Stephen S; Rotter, Jerome I; Post, Wendy S; Polak, Joseph F; Budoff, Matthew J; Bluemke, David A

    2016-06-01

    Previously identified single nucleotide polymorphisms (SNPs) in genome wide association studies (GWAS) of cardiovascular disease (CVD) in participants of mostly European descent were tested for association with subclinical cardiovascular disease (sCVD), coronary artery calcium score (CAC) and carotid intima media thickness (CIMT) in the Multi-Ethnic Study of Atherosclerosis (MESA). The data in this data in brief article correspond to the article Common Genetic Variants and Subclinical Atherosclerosis: The Multi-Ethnic Study of Atherosclerosis [1]. This article includes the demographic information of the participants analyzed in the article as well as graphical displays and data tables of the association of the selected SNPs with CAC and of the meta-analysis across ethnicities of the association of CIMT-c (common carotid), CIMT-I (internal carotid), CAC-d (CAC as dichotomous variable with CAC>0) and CAC-c (CAC as continuous variable, the log of the raw CAC score plus one) and CVD. The data tables corresponding to the 9p21 fine mapping experiment as well as the power calculations referenced in the article are also included. PMID:26958643

  9. On the air cleansing efficiency of an extended green wall: a CFD analysis of mechanistic details of transport processes.

    PubMed

    Joshi, Saumitra V; Ghosh, Sat

    2014-11-21

    The detrimental impact of rising air pollution levels in urban landscapes has become conspicuous over the last decade, particularly in developing countries. This novel numerical study quantifies the cleansing efficiency of green façades draped with a copiously growing tropical creeper Vernonia elaeagnifolia. Turbulent transport of SO2 to the leaf boundary layer and subsequent diffusion across stomatal pores into the mesophyllic cells is modeled at the micro level, including its ionic dissociation in the leaf׳s interior. A SEM analysis indicates stomatal dimensions and density. Whilst previous studies have used either spatially averaged equations or resistance models, a spatially discretized computational approach is adopted in this study. The resulting concentration distribution is used to calculate the deposition velocity on stomatal pores, which is then extrapolated over the entire façade to yield bulk pollutant removal rates. A deposition velocity of 1.53mms(-1) and 0.72mms(-1) is obtained for open and closed pores respectively, with removal rates equal to 1.11×10(-6)s(-1) and 1.05×10(-6)s(-1) for dry and humid weather respectively. Sensitivity studies on the removal rate are carried out based on humidity, stomatal aperture and leaf temperature. The removal rate dependence on the Leaf Area Index (LAI) is also investigated. It is inferred from simulations that vegetated façades are efficient at mitigation of residual pollution. PMID:25084039

  10. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    SciTech Connect

    Vikram, V.

    2015-07-29

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These “mass maps” provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey (DES) science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclusters and voids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N-body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8σ level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. In this study, we analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.

  11. Detailed analysis of association between common single nucleotide polymorphisms and subclinical atherosclerosis: The Multi-ethnic Study of Atherosclerosis

    PubMed Central

    Vargas, Jose D.; Manichaikul, Ani; Wang, Xin-Qun; Rich, Stephen S.; Rotter, Jerome I.; Post, Wendy S.; Polak, Joseph F.; Budoff, Matthew J.; Bluemke, David A.

    2016-01-01

    Previously identified single nucleotide polymorphisms (SNPs) in genome wide association studies (GWAS) of cardiovascular disease (CVD) in participants of mostly European descent were tested for association with subclinical cardiovascular disease (sCVD), coronary artery calcium score (CAC) and carotid intima media thickness (CIMT) in the Multi-Ethnic Study of Atherosclerosis (MESA). The data in this data in brief article correspond to the article Common Genetic Variants and Subclinical Atherosclerosis: The Multi-Ethnic Study of Atherosclerosis [1]. This article includes the demographic information of the participants analyzed in the article as well as graphical displays and data tables of the association of the selected SNPs with CAC and of the meta-analysis across ethnicities of the association of CIMT-c (common carotid), CIMT-I (internal carotid), CAC-d (CAC as dichotomous variable with CAC>0) and CAC-c (CAC as continuous variable, the log of the raw CAC score plus one) and CVD. The data tables corresponding to the 9p21 fine mapping experiment as well as the power calculations referenced in the article are also included. PMID:26958643

  12. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    NASA Astrophysics Data System (ADS)

    Vikram, V.; Chang, C.; Jain, B.; Bacon, D.; Amara, A.; Becker, M. R.; Bernstein, G.; Bonnett, C.; Bridle, S.; Brout, D.; Busha, M.; Frieman, J.; Gaztanaga, E.; Hartley, W.; Jarvis, M.; Kacprzak, T.; Kovács, A.; Lahav, O.; Leistedt, B.; Lin, H.; Melchior, P.; Peiris, H.; Rozo, E.; Rykoff, E.; Sánchez, C.; Sheldon, E.; Troxel, M. A.; Wechsler, R.; Zuntz, J.; Abbott, T.; Abdalla, F. B.; Armstrong, R.; Banerji, M.; Bauer, A. H.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Castander, F. J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Estrada, J.; Evrard, A. E.; Fausti Neto, A.; Fernandez, E.; Flaugher, B.; Fosalba, P.; Gerdes, D.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Li, T. S.; Maia, M. A. G.; Makler, M.; March, M.; Marshall, J.; Martini, P.; Merritt, K. W.; Miller, C. J.; Miquel, R.; Neilsen, E.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Sevilla, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Weller, J.

    2015-07-01

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These "mass maps" provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey (DES) science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclusters and voids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N -body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8 σ level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. In this work, we analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.

  13. "The goal is to be more flexible"--detailed analysis of goal setting in physiotherapy using a conversation analytic approach.

    PubMed

    Schoeb, Veronika

    2009-12-01

    Standards of practice in physiotherapy require professionals to set goals in collaboration with patients. Some evidence exists regarding outcome, but no studies have investigated the process of goal setting in orthopaedic physiotherapy. The objective of this pilot study is to describe the interaction between professionals and patients in the activity of goal setting. Three physiotherapists in an orthopaedic outpatient department audio-recorded initial patient consultations. Conversation analysis (hereafter CA), a qualitative research method, is used to illustrate participants' interaction in regards to turn taking, how talk is organised, what vocabulary they use and how they respond to each other's utterances. Four distinct phases are found: eliciting patients' preferences; introduction of goal setting activity; formulating goals; and closing the activity of goal setting. Formulating questions to elicit patients' preferences requires considerable effort. Constant adjustment is needed in order to achieve goals acceptable to both participants. Goal setting is time-consuming if the patient is actively involved. Closing of goal setting activity in physiotherapy is comparable to this activity in doctor-patient interaction. In conclusion it is not straightforward to formulate and negotiate treatment goals collaboratively with patients. A balance has to be found between the input of physiotherapists and patients during the process. PMID:19427808

  14. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    DOE PAGESBeta

    Vikram, V.

    2015-07-29

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These “mass maps” provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey (DES) science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclustersmore » and voids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N-body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8σ level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. In this study, we analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.« less

  15. Effects of neural progenitor cells on post-stroke neurological impairment—a detailed and comprehensive analysis of behavioral tests

    PubMed Central

    Doeppner, Thorsten R.; Kaltwasser, Britta; Bähr, Mathias; Hermann, Dirk M.

    2014-01-01

    Systemic transplantation of neural progenitor cells (NPCs) in rodents reduces functional impairment after cerebral ischemia. In light of upcoming stroke trials regarding safety and feasibility of NPC transplantation, experimental studies have to successfully analyze the extent of NPC-induced neurorestoration on the functional level. However, appropriate behavioral tests for analysis of post-stroke motor coordination deficits and cognitive impairment after NPC grafting are not fully established. We therefore exposed male C57BL6 mice to either 45 min (mild) or 90 min (severe) of cerebral ischemia, using the thread occlusion model followed by intravenous injection of PBS or NPCs 6 h post-stroke with an observation period of three months. Post-stroke motor coordination was assessed by means of the rota rod, tight rope, corner turn, inclined plane, grip strength, foot fault, adhesive removal, pole test and balance beam test, whereas cognitive impairment was analyzed using the water maze, the open field and the passive avoidance test. Significant motor coordination differences after both mild and severe cerebral ischemia in favor of NPC-treated mice were observed for each motor coordination test except for the inclined plane and the grip strength test, which only showed significant differences after severe cerebral ischemia. Cognitive impairment after mild cerebral ischemia was successfully assessed using the water maze test, the open field and the passive avoidance test. On the contrary, the water maze test was not suitable in the severe cerebral ischemia paradigm, as it too much depends on motor coordination capabilities of test mice. In terms of both reliability and cost-effectiveness considerations, we thus recommend the corner turn, foot fault, balance beam, and open field test, which do not depend on durations of cerebral ischemia. PMID:25374509

  16. Effects of neural progenitor cells on post-stroke neurological impairment-a detailed and comprehensive analysis of behavioral tests.

    PubMed

    Doeppner, Thorsten R; Kaltwasser, Britta; Bähr, Mathias; Hermann, Dirk M

    2014-01-01

    Systemic transplantation of neural progenitor cells (NPCs) in rodents reduces functional impairment after cerebral ischemia. In light of upcoming stroke trials regarding safety and feasibility of NPC transplantation, experimental studies have to successfully analyze the extent of NPC-induced neurorestoration on the functional level. However, appropriate behavioral tests for analysis of post-stroke motor coordination deficits and cognitive impairment after NPC grafting are not fully established. We therefore exposed male C57BL6 mice to either 45 min (mild) or 90 min (severe) of cerebral ischemia, using the thread occlusion model followed by intravenous injection of PBS or NPCs 6 h post-stroke with an observation period of three months. Post-stroke motor coordination was assessed by means of the rota rod, tight rope, corner turn, inclined plane, grip strength, foot fault, adhesive removal, pole test and balance beam test, whereas cognitive impairment was analyzed using the water maze, the open field and the passive avoidance test. Significant motor coordination differences after both mild and severe cerebral ischemia in favor of NPC-treated mice were observed for each motor coordination test except for the inclined plane and the grip strength test, which only showed significant differences after severe cerebral ischemia. Cognitive impairment after mild cerebral ischemia was successfully assessed using the water maze test, the open field and the passive avoidance test. On the contrary, the water maze test was not suitable in the severe cerebral ischemia paradigm, as it too much depends on motor coordination capabilities of test mice. In terms of both reliability and cost-effectiveness considerations, we thus recommend the corner turn, foot fault, balance beam, and open field test, which do not depend on durations of cerebral ischemia. PMID:25374509

  17. Sodium abundances of AGB and RGB stars in Galactic globular clusters. I. Analysis and results of NGC 2808

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Primas, F.; Charbonnel, C.; Van der Swaelmen, M.; Bono, G.; Chantereau, W.; Zhao, G.

    2016-07-01

    Context. Galactic globular clusters (GC) are known to have multiple stellar populations and be characterised by similar chemical features, e.g. O-Na anti-correlation. While second-population stars, identified by their Na overabundance, have been found from the main sequence turn-off up to the tip of the red giant branch (RGB) in various Galactic GCs, asymptotic giant branch (AGB) stars have rarely been targeted. The recent finding that NGC 6752 lacks an Na-rich AGB star has thus triggered new studies on AGB stars in GCs, since this result questions our basic understanding of GC formation and stellar evolution theory. Aims: We aim to compare the Na abundance distributions of AGB and RGB stars in Galactic GCs and investigate whether the presence of Na-rich stars on the AGB is metallicity-dependent. Methods: With high-resolution spectra obtained with the multi-object high-resolution spectrograph FLAMES on ESO/VLT, we derived accurate Na abundances for 31 AGB and 40 RGB stars in the Galactic GC NGC 2808. Results: We find that NGC 2808 has a mean metallicity of -1.11 ± 0.08 dex, in good agreement with earlier analyses. Comparable Na abundance dispersions are derived for our AGB and RGB samples, with the AGB stars being slightly more concentrated than the RGB stars. The ratios of Na-poor first-population to Na-rich second-population stars are 45:55 in the AGB sample and 48:52 in the RGB sample. Conclusions: NGC 2808 has Na-rich second-population AGB stars, which turn out to be even more numerous - in relative terms - than their Na-poor AGB counterparts and the Na-rich stars on the RGB. Our findings are well reproduced by the fast rotating massive stars scenario and they do not contradict the recent results that there is not an Na-rich AGB star in NGC 6752. NGC 2808 thus joins the larger group of Galactic GCs for which Na-rich second-population stars on the AGB have recently been found. Based on observations made with ESO telescopes at the La Silla Paranal Observatory

  18. High-resolution abundance analysis of red giants in the metal-poor bulge globular cluster HP 1

    NASA Astrophysics Data System (ADS)

    Barbuy, B.; Cantelli, E.; Vemado, A.; Ernandes, H.; Ortolani, S.; Saviane, I.; Bica, E.; Minniti, D.; Dias, B.; Momany, Y.; Hill, V.; Zoccali, M.; Siqueira-Mello, C.

    2016-06-01

    Context. The globular cluster HP 1 is projected at only 3.̊33 from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch (BHB) and a metallicity of [Fe/H] ≈ -1.0. This means that it probably is one of the oldest objects in the Galaxy. Abundance ratios can reveal the nucleosynthesis pattern of the first stars as well as the early chemical enrichment and early formation of stellar populations. Aims: High-resolution spectra obtained for six stars were analyzed to derive the abundances of the light elements C, N, O, Na, and Al, the alpha-elements Mg, Si, Ca, and Ti, and the heavy elements Sr, Y, Zr, Ba, La, and Eu. Methods: High-resolution spectra of six red giants that are confirmed members of the bulge globular cluster HP 1 were obtained with the 8 m VLT UT2-Kueyen telescope with the UVES spectrograph in FLAMES-UVES configuration. The spectroscopic parameter derivation was based on the excitation and ionization equilibrium of Fe i and Fe ii. Results: We confirm a mean metallicity of [Fe/H] = -1.06 ± 0.10, by adding the two stars that were previously analyzed in HP 1. The alpha-elements O and Mg are enhanced by about +0.3 ≲ [O,Mg/Fe] ≲ +0.5 dex, Si is moderately enhanced with +0.15 ≲ [Si/Fe] ≲ +0.35 dex, while Ca and Ti show lower values of -0.04 ≲ [Ca,Ti/Fe] ≲ +0.28 dex. The r-element Eu is also enhanced with [Eu/Fe] ≈ +0.4, which together with O and Mg is indicative of early enrichment by type II supernovae. Na and Al are low, but it is unclear if Na-O are anticorrelated. The heavy elements are moderately enhanced, with -0.20 < [La/Fe] < +0.43 dex and 0.0 < [Ba/Fe] < +0.75 dex, which is compatible with r-process formation. The spread in Y, Zr, Ba, and La abundances, on the other hand, appears to be compatible with the spinstar scenario or other additional mechanisms such as the weak r-process. Observations collected at the European Southern

  19. Detailed Analysis of Sequence Changes Occurring during vlsE Antigenic Variation in the Mouse Model of Borrelia burgdorferi Infection

    PubMed Central

    Coutte, Loïc; Botkin, Douglas J.; Gao, Lihui; Norris, Steven J.

    2009-01-01

    Lyme disease Borrelia can infect humans and animals for months to years, despite the presence of an active host immune response. The vls antigenic variation system, which expresses the surface-exposed lipoprotein VlsE, plays a major role in B. burgdorferi immune evasion. Gene conversion between vls silent cassettes and the vlsE expression site occurs at high frequency during mammalian infection, resulting in sequence variation in the VlsE product. In this study, we examined vlsE sequence variation in B. burgdorferi B31 during mouse infection by analyzing 1,399 clones isolated from bladder, heart, joint, ear, and skin tissues of mice infected for 4 to 365 days. The median number of codon changes increased progressively in C3H/HeN mice from 4 to 28 days post infection, and no clones retained the parental vlsE sequence at 28 days. In contrast, the decrease in the number of clones with the parental vlsE sequence and the increase in the number of sequence changes occurred more gradually in severe combined immunodeficiency (SCID) mice. Clones containing a stop codon were isolated, indicating that continuous expression of full-length VlsE is not required for survival in vivo; also, these clones continued to undergo vlsE recombination. Analysis of clones with apparent single recombination events indicated that recombinations into vlsE are nonselective with regard to the silent cassette utilized, as well as the length and location of the recombination event. Sequence changes as small as one base pair were common. Fifteen percent of recovered vlsE variants contained “template-independent” sequence changes, which clustered in the variable regions of vlsE. We hypothesize that the increased frequency and complexity of vlsE sequence changes observed in clones recovered from immunocompetent mice (as compared with SCID mice) is due to rapid clearance of relatively invariant clones by variable region-specific anti-VlsE antibody responses. PMID:19214205

  20. Sequence-Based Analysis Uncovers an Abundance of Non-Coding RNA in the Total Transcriptome of Mycobacterium tuberculosis

    PubMed Central

    Arnvig, Kristine B.; Comas, Iñaki; Thomson, Nicholas R.; Houghton, Joanna; Boshoff, Helena I.; Croucher, Nicholas J.; Rose, Graham; Perkins, Timothy T.; Parkhill, Julian; Dougan, Gordon; Young, Douglas B.

    2011-01-01

    RNA sequencing provides a new perspective on the genome of Mycobacterium tuberculosis by revealing an extensive presence of non-coding RNA, including long 5’ and 3’ untranslated regions, antisense transcripts, and intergenic small RNA (sRNA) molecules. More than a quarter of all sequence reads mapping outside of ribosomal RNA genes represent non-coding RNA, and the density of reads mapping to intergenic regions was more than two-fold higher than that mapping to annotated coding sequences. Selected sRNAs were found at increased abundance in stationary phase cultures and accumulated to remarkably high levels in the lungs of chronically infected mice, indicating a potential contribution to pathogenesis. The ability of tubercle bacilli to adapt to changing environments within the host is critical to their ability to cause disease and to persist during drug treatment; it is likely that novel post-transcriptional regulatory networks will play an important role in these adaptive responses. PMID:22072964

  1. Abundance and Temperature Dependency of Protein-Protein Interaction Revealed by Interface Structure Analysis and Stability Evolution

    NASA Astrophysics Data System (ADS)

    He, Yi-Ming; Ma, Bin-Guang

    2016-05-01

    Protein complexes are major forms of protein-protein interactions and implement essential biological functions. The subunit interface in a protein complex is related to its thermostability. Though the roles of interface properties in thermal adaptation have been investigated for protein complexes, the relationship between the interface size and the expression level of the subunits remains unknown. In the present work, we studied this relationship and found a positive correlation in thermophiles rather than mesophiles. Moreover, we found that the protein interaction strength in complexes is not only temperature-dependent but also abundance-dependent. The underlying mechanism for the observed correlation was explored by simulating the evolution of protein interface stability, which highlights the avoidance of misinteraction. Our findings make more complete the picture of the mechanisms for protein complex thermal adaptation and provide new insights into the principles of protein-protein interactions.

  2. Functional analysis of a highly conserved abundant larval transcript-2 (alt-2) intron 2 repeat region of lymphatic filarial parasites.

    PubMed

    Sakthidevi, Moorthy; Hoti, Sugeerappa Laxmanappa; Kaliraj, Perumal

    2014-06-01

    The filarial-specific protein abundant larval transcript-2 (ALT-2) is expressed exclusively in the infective larval stage (L3) and is a crucial protein for establishing immunopathogenesis in human hosts. The alt-2 gene has a conserved minisatellite repeat (29 or 27bp) in intron 2 (IR2) whose significance within lymphatic filarial species is unknown. Here, we report the role of IR2 in the regulation of alt-2 gene expression using an in vitro model. Using electrophoretic mobility shift assays, we identified the presence of a putative nuclear protein binding region within IR2. Subsequent transient expression experiments in eukaryotic cell lines demonstrated that the IR2 downregulated the expression of a downstream luciferase reporter gene, which was further validated with RT-PCR. We therefore identify IR2 as a suppressor element that regulates L3 stage-specific expression of alt-2. PMID:24681262

  3. Abundance and Temperature Dependency of Protein-Protein Interaction Revealed by Interface Structure Analysis and Stability Evolution

    PubMed Central

    He, Yi-Ming; Ma, Bin-Guang

    2016-01-01

    Protein complexes are major forms of protein-protein interactions and implement essential biological functions. The subunit interface in a protein complex is related to its thermostability. Though the roles of interface properties in thermal adaptation have been investigated for protein complexes, the relationship between the interface size and the expression level of the subunits remains unknown. In the present work, we studied this relationship and found a positive correlation in thermophiles rather than mesophiles. Moreover, we found that the protein interaction strength in complexes is not only temperature-dependent but also abundance-dependent. The underlying mechanism for the observed correlation was explored by simulating the evolution of protein interface stability, which highlights the avoidance of misinteraction. Our findings make more complete the picture of the mechanisms for protein complex thermal adaptation and provide new insights into the principles of protein-protein interactions. PMID:27220911

  4. The Penn State - Toruń Centre for Astronomy Planet Search stars. II. Lithium abundance analysis of the red giant clump sample

    NASA Astrophysics Data System (ADS)

    Adamów, M.; Niedzielski, A.; Villaver, E.; Wolszczan, A.; Nowak, G.

    2014-09-01

    Context. Standard stellar evolution theory does not predict existence of Li-rich giant stars. Several mechanisms for Li-enrichment have been proposed to operate at certain locations inside some stars. The actual mechanism operating in real stars is still unknown. Aims: Using the sample of 348 stars from the Penn State - Toruń Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we investigate various channels of Li enrichment in giants. We also study Li-overabundant giants in more detail in search for origin of their peculiarities. Methods: Our work is based on the Hobby-Eberly Telescope spectra obtained with the High Resolution Spectrograph, which we use for determination of abundances and rotational velocities. The Li abundance was determined from the 7Li λ670.8 nm line, while we use a more extended set of lines for α-elements abundances. In a series of Kolmogorov-Smirnov tests, we compare Li-overabundant giants with other stars in the sample. We also use available IR photometric and kinematical data in search for evidence of mass-loss. We investigate properties of the most Li-abundant giants in more detail by using multi-epoch precise radial velocities. Results: We present Li and α-elements abundances, as well as rotational velocities for 348 stars. We detected Li in 92 stars, of which 82 are giants. Eleven of them show significant Li abundance A(Li)NLTE> 1.4 and seven of them are Li-overabundant objects, according to common criterion of A(Li) > 1.5 and their location on HR diagram, including TYC 0684-00553-1 and TYC 3105-00152-1, which are two giants with Li abundances close to meteoritic level. For another 271 stars, upper limits of Li abundance are presented. We confirmed three objects with increased stellar rotation. We show that Li-overabundant giants are among the most massive stars from our sample and show larger than average

  5. The solar abundance of thulium

    NASA Technical Reports Server (NTRS)

    Ross, J. E.; Aller, L. H.

    1974-01-01

    Consideration of one relatively unblended line of the solar spectrum, namely, the 3131.258-A line of Tm II, which yields a thulium abundance of 0.80 plus or minus 0.10 with the Corliss and Bozman (1962) f-value. The uncertainty of this figure is discussed in conjunction with the contradictory findings of some other investigators. The need for further detailed study of the lanthanides by the method of spectrum synthesis is pointed out.

  6. A Chemical Abundance Analysis of Stars Believed to be Metal Poor Members of the Galactic Stellar Thick Disk

    NASA Astrophysics Data System (ADS)

    Simmerer, Jennifer Ann

    Galactic formation models have long sought to reproduce the observed chemical and kinematical properties of the Milky Way's stellar halo and disk. Recently it is the so-called ``intermediate population'', the stellarthick disk, that is driving advances in our understanding of the formation of spiral galaxies. The thick disk is kinematically more like the thin disk than the halo, for all the thick disk has a velocity dispersion twice that of the thin diskand rotates ~40 km/s more slowly. It is generally accepted that the thick disk's metallicity distribution function peaks at a lower metallicity than the thin disk but at higher metallicity than the halo. The lower bound of the thick disk is still uncertain, as many observational studies have found only a few thick disk candidate. stars or clusters that are more metal poor than [Fe/H]=--1. Beers et al. (2002) have so far proposed the largest sample of metal poor thick disk. candidates, presenting 9 stars at [Fe/H]=-1.2 or lower and 46 more stars at [Fe/H]=-1 or lower, all of which are believed to belong to the thick disk. Beers et al. (2002) present possible thick disk stars as metal poor as [Fe/H]~ -2.5, roughly 1 dex lower than is suggested by current Galactic formation models (Brook et al., 2005). This study is a high-resolution spectroscopic follow-up of 29 of the stars Beers et al. (2002) and Chiba & Beers (2000) identify as potiential metal poor members of the thick disk and an additional 40 stars from the cannonical thick disk, halo, and thin disk. None of the very metal-poor stars identified by Beers et al. (2002) can be confirmed as members of the thick disk and many are not metal poor at all. Only two stars more metal poor than [Fe/H]=--1.2 retain their thick disk membership. These two stars exhibit some of the. chemical characteristics of the cannonical thick disk: high alpha-element abundances and a relatively low s-/r- process element ratio. Also of interest are. six stars with thin disk kinematic

  7. VizieR Online Data Catalog: B6-B9.5 stars abundance analysis (Niemczura+, 2009)

    NASA Astrophysics Data System (ADS)

    Niemczura, E.; Morel, T.; Aerts, C.

    2009-10-01

    The observational material consists of the high-resolution (R~40000-50000) spectroscopic observations of B-type stars obtained with the ELODIE and FEROS spectrographs. The ELODIE spectrograph was attached to the 1.93m telescope at the Observatoire de Haute-Provence, France. The FEROS spectrograph was installed on the 1.52m and 2.2m telescopes at La Silla, Chile. Both instruments are cross-dispersed, fibre-fed echelle spectrographs. Typical signal-to-noise ratios of the spectra range from 100 to 150 at 550nm. The wavelength intervals covered are 390-680nm and 380-910nm for ELODIE and FEROS, respectively. In our initial sample, we have 160 FEROS spectra and 62 ELODIE spectra of B-type stars. Only the spectroscopic observations of the B6-B9.5 stars available in the GAUDI archive are analysed in this paper. We also excluded Be stars, supergiants and spectroscopic binaries for which the lines of two stars were visible in the spectra. Basic information about the analysed stars, including spectral type, name of the spectrograph, observation date in UT, V magnitude, interstellar reddening, indications of binarity, and abundance determinations in the literature are given in Table 1. (4 data files).

  8. Two-dimensional gel electrophoresis analysis of the abundance of virulent exoproteins of group A streptococcus caused by environmental changes.

    PubMed

    Nakamura, Tadahiro; Hasegawa, Tadao; Torii, Keizo; Hasegawa, Yoshinori; Shimokata, Kaoru; Ohta, Michio

    2004-01-01

    Group A streptococci regulate the expression of virulence factors in response to environmental change. In order to investigate this mechanism, the growth of group A streptococci and the abundance of virulent exoprotein production in culture supernatant were analyzed by two-dimensional gel electrophoresis (2-D electrophoresis) under several culture conditions. Judging from alterations in their growth, group A streptococci were affected by various environmental stresses. Under high O(2) and low CO(2 )concentrations, streptococcal pyrogenic exotoxin B (SpeB) and streptococcal pyrogenic exotoxin F (SpeF) significantly decreased, and the streptococcal inhibitor of complement (Sic) increased. At 30 degrees C, increases in endo-beta- N-acetylglucosaminidase (EndoS) and alpha-amylase were also detected, while at 41 degrees C EndoS became undetectable and SpeB and SpeF decreased. Sic, SpeF and mitogenic factor 3 (Mf3) decreased when cells were cultured in higher NaCl concentrations, and EndoS disappeared following culture of the cells in high glucose concentration. An increase in acid phosphatase and a decrease in several other proteins were detected when the cells were cultivated in high iron concentrations. These results suggest that group A streptococci have a versatile adaptation system that responds to several environmental stresses by altering the level of exoprotein production. PMID:14673516

  9. VizieR Online Data Catalog: Chemical abundances of solar neighbourhood dwarfs (Bensby+, 2014)

    NASA Astrophysics Data System (ADS)

    Bensby, T.; Feltzing, S.; Oey, M. S.

    2014-01-01

    In the following tables we give stellar parameters, stellar ages, kinematical parameters, orbital parameters, and detailed elemental abundances for O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, Y, and Ba for 714 nearby F and G dwarf stars. We also list the atomic data used (oscillator strengths), as well as equivalent widths and abundances for individual lines in the Sun. Finally we list stars that were observed but not analysed as they turned out to be either spectroscopic binaries or rotated too fast to allow a proper abundance analysis. (3 data files).

  10. Coronal abundances and their variation

    NASA Technical Reports Server (NTRS)

    Saba, Julia L. R.

    1995-01-01

    This contract supports the investigation of elemental abundances in the solar corona, principally through analysis of high-resolution soft X-ray spectra from the Flat Crystal Spectrometer on the Solar Maximum Mission. The goals of the study are a characterization of the mean values of relative abundances of elements accessible in the FCS data, and information on the extent and circumstances of their variability. This report is a summation of the data analysis and reporting activities which occurred during the period of 15 April 1994 to 15 April 1995.

  11. Coronal Abundances and Their Variation

    NASA Technical Reports Server (NTRS)

    Saba, Julia L. R.

    1996-01-01

    This contract supported the investigation of elemental abundances in the solar corona, principally through analysis of high-resolution soft X-ray spectra from the Flat Crystal Spectrometer on NASA's Solar Maximum Mission. The goals of the study were a characterization of the mean values of relative abundances of elements accessible in the FCS data, and information on the extent and circumstances of their variability. This is the Final Report, summarizing the data analysis and reporting activities which occurred during the period of performance, June 1993 - December 1996.

  12. Genome-wide identification, structural analysis and new insights into late embryogenesis abundant (LEA) gene family formation pattern in Brassica napus

    PubMed Central

    Liang, Yu; Xiong, Ziyi; Zheng, Jianxiao; Xu, Dongyang; Zhu, Zeyang; Xiang, Jun; Gan, Jianping; Raboanatahiry, Nadia; Yin, Yongtai; Li, Maoteng

    2016-01-01

    Late embryogenesis abundant (LEA) proteins are a diverse and large group of polypeptides that play important roles in desiccation and freezing tolerance in plants. The LEA family has been systematically characterized in some plants but not Brassica napus. In this study, 108 BnLEA genes were identified in the B. napus genome and classified into eight families based on their conserved domains. Protein sequence alignments revealed an abundance of alanine, lysine and glutamic acid residues in BnLEA proteins. The BnLEA gene structure has few introns (<3), and they are distributed unevenly across all 19 chromosomes in B. napus, occurring as gene clusters in chromosomes A9, C2, C4 and C5. More than two-thirds of the BnLEA genes are associated with segmental duplication. Synteny analysis revealed that most LEA genes are conserved, although gene losses or gains were also identified. These results suggest that segmental duplication and whole-genome duplication played a major role in the expansion of the BnLEA gene family. Expression profiles analysis indicated that expression of most BnLEAs was increased in leaves and late stage seeds. This study presents a comprehensive overview of the LEA gene family in B. napus and provides new insights into the formation of this family. PMID:27072743

  13. Genome-wide identification, structural analysis and new insights into late embryogenesis abundant (LEA) gene family formation pattern in Brassica napus.

    PubMed

    Liang, Yu; Xiong, Ziyi; Zheng, Jianxiao; Xu, Dongyang; Zhu, Zeyang; Xiang, Jun; Gan, Jianping; Raboanatahiry, Nadia; Yin, Yongtai; Li, Maoteng

    2016-01-01

    Late embryogenesis abundant (LEA) proteins are a diverse and large group of polypeptides that play important roles in desiccation and freezing tolerance in plants. The LEA family has been systematically characterized in some plants but not Brassica napus. In this study, 108 BnLEA genes were identified in the B. napus genome and classified into eight families based on their conserved domains. Protein sequence alignments revealed an abundance of alanine, lysine and glutamic acid residues in BnLEA proteins. The BnLEA gene structure has few introns (<3), and they are distributed unevenly across all 19 chromosomes in B. napus, occurring as gene clusters in chromosomes A9, C2, C4 and C5. More than two-thirds of the BnLEA genes are associated with segmental duplication. Synteny analysis revealed that most LEA genes are conserved, although gene losses or gains were also identified. These results suggest that segmental duplication and whole-genome duplication played a major role in the expansion of the BnLEA gene family. Expression profiles analysis indicated that expression of most BnLEAs was increased in leaves and late stage seeds. This study presents a comprehensive overview of the LEA gene family in B. napus and provides new insights into the formation of this family. PMID:27072743

  14. Detailed structural analysis of epitaxial MBE-grown Fe/Cr superlattices by x-ray diffraction and transmission-electron spectroscopy

    SciTech Connect

    Gomez, M.E.; Santamaria, J.; Kim, S.; Schuller, Ivan K.; Krishnan, Kannan M.

    2005-03-15

    We have performed a detailed quantitative structural analysis of epitaxial [Fe(3 nm)/Cr(1.2 nm)]{sub 20} superlattices by low- and high-angle x-ray diffraction, and energy-filtered transmission electron microscopy on cross-section samples. The interface roughness was changed systematically by varying the substrate temperature (150-250 deg. C) maintaining all other growth parameters fixed. Direct imaging of the interfaces allows examining the roughness of the individual interfaces and its evolution with thickness. A statistical analysis of the local interface width for the individual layers supplies the roughness static and dynamic exponents. High-temperature samples (250 deg. C) show roughness decreasing with thickness as a result of surface-diffusion-dominated growth. Low-temperature samples (150 deg. C) show anomalous non-self-affine roughness characterized by a time-dependent local interface width.

  15. Detailed Analysis of the Binding Mode of Vanilloids to Transient Receptor Potential Vanilloid Type I (TRPV1) by a Mutational and Computational Study.

    PubMed

    Ohbuchi, Katsuya; Mori, Yoshikazu; Ogawa, Kazuo; Warabi, Eiji; Yamamoto, Masahiro; Hirokawa, Takatsugu

    2016-01-01

    Transient receptor potential vanilloid type 1 (TRPV1) is a non-selective cation channel and a multimodal sensor protein. Since the precise structure of TRPV1 was obtained by electron cryo-microscopy, the binding mode of representative agonists such as capsaicin and resiniferatoxin (RTX) has been extensively characterized; however, detailed information on the binding mode of other vanilloids remains lacking. In this study, mutational analysis of human TRPV1 was performed, and four agonists (capsaicin, RTX, [6]-shogaol and [6]-gingerol) were used to identify amino acid residues involved in ligand binding and/or modulation of proton sensitivity. The detailed binding mode of each ligand was then simulated by computational analysis. As a result, three amino acids (L518, F591 and L670) were newly identified as being involved in ligand binding and/or modulation of proton sensitivity. In addition, in silico docking simulation and a subsequent mutational study suggested that [6]-gingerol might bind to and activate TRPV1 in a unique manner. These results provide novel insights into the binding mode of various vanilloids to the channel and will be helpful in developing a TRPV1 modulator. PMID:27606946

  16. s-Process Element Abundance Results for 47 Tuc Stars Using SALT

    NASA Astrophysics Data System (ADS)

    Worley, C. C.; Cottrell, P. L.; Wylie de Boer, E. C.

    2008-04-01

    Eleven giant branch stars in 47 Tucanæ were observed using the Robert Stobie Spectro-graph (RSS) on the Southern African Large Telescope during the performance verification phase of this instrument. These stars were analysed as part of a quest to investigate s-process element abundances throughout the colour-magnitude diagram of 47 Tucanæ. No abundance variations of Zr, Ba, Nd and Eu were found in these eleven stars, such that [X/Fe] = 0.0+/-0.5 3dex. Further, theoretical analysis indicates that the maximum resolution on RSS and AAOmega on the Anglo-Australian Telescope is sufficient to detect s-process element abundance variations. More detailed discussion on the abundance analysis of these stars and the theoretical analysis of spectrograph resolution can be found in [l].

  17. VizieR Online Data Catalog: Fe-group elemental abundance analysis in HD84937 (Sneden+, 2016)

    NASA Astrophysics Data System (ADS)

    Sneden, C.; Cowan, J. J.; Kobayashi, C.; Pignatari, M.; Lawler, J. E.; den Hartog, E. A.; Wood, M. P.

    2016-04-01

    Solar and HD 84937 data sets are the same as in previous papers of this series. The spectra have been discussed in detail by Lawler et al. (2013ApJS..205...11L). For the Sun we used the photospheric center-of-disk spectrum of Delbouille et al. (1973apds.book.....D). The ground-based spectrum of HD 84937 was obtained from the ESO Very Large Telescope UVES archive. It extends over 3100<~λ<~10000Å, with resolving power R~60000 and signal-to-noise ratio S/N~100 at 3500Å. The vacuum-UV spectrum of HD 84937 comes from the Hubble Space Telescope Imaging Spectrograph (HST/STIS) public archive, having been part of proposal #7402 (PI: R. C. Peterson) with a wavelength range 2280<~λ<~3120Å and R~25000. (2 data files).

  18. An Abundance Analysis of Two Carbon-Rich Proto-Planetary Nebulae: IRAS Z02229+6208 And IRAS 07430+1115

    NASA Technical Reports Server (NTRS)

    Reddy, Bacham E.; Bakker, Eric J.; Hrivnak, Bruce J.

    1999-01-01

    In this paper, we present an LTE abundance analysis of two new proto-planetary nebulae, IRAS Z02229 + 6208 and IRAS 07430 + 1115, based on high-resolution (R approximately equal 55,000) optical echelle spectra. Results show that both stars are metal-poor ([Fe/H] = -0.5) and overabundant in C, N, and s-process elements. The average elemental abundances are [C/Fe] = +0.8, [N/Fe] = +1.2, and [s-process/Fe] = +1.4 for IRAS Z02229 + 6208, and [C/Fe] = +0.6, [N/Fe] = +0.4, and [s-process/Fe] = +1.6 for IRAS 07430+ 1115. These abundances suggest that the stars have experienced nucleo-synthesis on the asymptotic giant branch (AGB), and the resultant products of CNO, 3alpha, and s-process reactions were brought to the photosphere during shell flashes and deep mixing episodes during the AGB phase of their evolution. Of major significance is the measurement of a high Li abundance in both stars, log epsilon(Li) approximately equal 2.3 and 2.4 for IRAS Z02229 + 6208 and IRAS 07430 + 1115, respectively. This may be the result of hot bottom burning, below the deep convective zone. We also present an analysis of the circumstellar molecular (C2 and CN) and atomic (Na I and K I) absorption spectra of both stars. We derive rotational temperatures, column densities, and envelope expansion velocities using molecular C2 Phillips and CN Red system bands. The values derived for expansion velocities, 8-14 km/s, are typical of the values found for post-AGB stars. IRAS 07430+ 1115 is unusual in that it shows P Cygni-shaped C2 emission profiles in the spectra of the circumstellar envelope. A minimum distance for IRAS Z02229+6208, determined from interstellar Na I lines, suggests that it is evolved from an intermediate-mass star. Including these two stars, the number of post-AGB stars for which clear C, N, and s-process elemental overabundances are found rises to eight. IRAS Z02229 + 6208 is known to possess the 21 micron emission feature in its mid-infrared spectrum; these results support the

  19. Solar and stellar photospheric abundances

    NASA Astrophysics Data System (ADS)

    Allende Prieto, Carlos

    2016-07-01

    The determination of photospheric abundances in late-type stars from spectroscopic observations is a well-established field, built on solid theoretical foundations. Improving those foundations to refine the accuracy of the inferred abundances has proven challenging, but progress has been made. In parallel, developments on instrumentation, chiefly regarding multi-object spectroscopy, have been spectacular, and a number of projects are collecting large numbers of observations for stars across the Milky Way and nearby galaxies, promising important advances in our understanding of galaxy formation and evolution. After providing a brief description of the basic physics and input data involved in the analysis of stellar spectra, a review is made of the analysis steps, and the available tools to cope with large observational efforts. The paper closes with a quick overview of relevant ongoing and planned spectroscopic surveys, and highlights of recent research on photospheric abundances.

  20. Analysis of the factors that affect the distribution and abundance of three Neobuxbaumia species (Cactaceae) that differ in their degree of rarity

    NASA Astrophysics Data System (ADS)

    Ruedas, Marcela; Valverde, Teresa; Zavala-Hurtado, José Alejandro

    2006-03-01

    We studied three species of columnar cacti in the genus Neobuxbaumia which differ in their degree of rarity: Neobuxbaumia macrocephala (the rarest), Neobuxbaumia tetetzo (intermediate), and Neobuxbaumia mezcalaensis (the most common). To investigate the ecological factors that limit their distribution and abundance, we surveyed 80 localities within the region of Tehuacan-Cuicatlán, in Central Mexico. At each locality we measured several environmental variables, and the density of the Neobuxbaumia populations present. We used a principal component analysis (PCA) to identify the factors that are associated to the presence/absence of each species. Additionally, we carried out multiple regressions between environmental variables and population density to test whether the variation in these variables was related to changes in abundance. The results show that factors significantly affecting the distribution of these species are mean annual temperature, altitude, rainfall, and soil properties such as texture and organic matter content. N. mezcalaensis reaches maximum population densities of 14,740 plants per ha (average density = 3943 plants per ha) and is associated with localities with relatively abundant rainfall. N. tetetzo shows maximum population densities of 14,060 plants per ha (average = 3070 plants per ha), and is associated with sites located at high latitudes and with high phosphorous content in the soil. The rarest species, N. macrocephala, shows maximum densities of 1180 plants per ha (average = 607 plants per ha) and is associated with localities with high soil calcium content. The distribution of this species is limited to sites with specific values of the environmental variables recorded, conferring it a high habitat specificity which accounts for its rarity.

  1. A geostatistical analysis of small-scale spatial variability in bacterial abundance and community structure in salt marsh creek bank sediments

    NASA Technical Reports Server (NTRS)

    Franklin, Rima B.; Blum, Linda K.; McComb, Alison C.; Mills, Aaron L.

    2002-01-01

    Small-scale variations in bacterial abundance and community structure were examined in salt marsh sediments from Virginia's eastern shore. Samples were collected at 5 cm intervals (horizontally) along a 50 cm elevation gradient, over a 215 cm horizontal transect. For each sample, bacterial abundance was determined using acridine orange direct counts and community structure was analyzed using randomly amplified polymorphic DNA fingerprinting of whole-community DNA extracts. A geostatistical analysis was used to determine the degree of spatial autocorrelation among the samples, for each variable and each direction (horizontal and vertical). The proportion of variance in bacterial abundance that could be accounted for by the spatial model was quite high (vertical: 60%, horizontal: 73%); significant autocorrelation was found among samples separated by 25 cm in the vertical direction and up to 115 cm horizontally. In contrast, most of the variability in community structure was not accounted for by simply considering the spatial separation of samples (vertical: 11%, horizontal: 22%), and must reflect variability from other parameters (e.g., variation at other spatial scales, experimental error, or environmental heterogeneity). Microbial community patch size based upon overall similarity in community structure varied between 17 cm (vertical) and 35 cm (horizontal). Overall, variability due to horizontal position (distance from the creek bank) was much smaller than that due to vertical position (elevation) for both community properties assayed. This suggests that processes more correlated with elevation (e.g., drainage and redox potential) vary at a smaller scale (therefore producing smaller patch sizes) than processes controlled by distance from the creek bank. c2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

  2. Detailed structure of the Philippine Sea plate subducting along the Nankai Trough, western Japan, inferred from high-frequency seismic wave analysis

    NASA Astrophysics Data System (ADS)

    Furumura, T.; Padhy, S.; Maeda, T.

    2012-12-01

    A detailed structure of the subducting Philippine Sea plate (PHP) along the Nankai trough in western Japan was studied by analyzing waveforms recorded at dense Hi-net stations in Japan. It is well recognized that the waveforms from intraplate earthquakes dominate in high-frequency (f >1 Hz) signals due to the waveguide effect of the subducting slab (Furumura and Kennett, 2005; 2008). This results in distorted pattern of intensity and peak ground acceleration (PGA) above the hypocenter with a substantial elongation of isoseismic contours correlated with the configuration of the isodepth contours of the subducting PHP beneath western Japan. A detailed analysis of the dense Hi-net waveform data from the intermediate-depth PHP event shows that the high-frequency S-wave signals suddenly disappear as the waves propagate the zone away from the Kii Channel to the boundary of Hyogo and Okayama prefectures and large S-to-P conversion occurs before the arrival of S-wave. Such anomalies do not occur for shallow and deep earthquakes occurring outside the PHP. These observations support the recent debate on the complexities of the configuration of the PHP subducting beneath western Japan such as that shown by Shiomi et al. (2008) based on receiver function images and the PHP-split model beneath the Kii channel shown by Ide et al.(2010) based on the analysis of comprehensive geophysical data. In order to explain the observations associated with sudden lateral change in the PHP structure, we conducted finite difference method (FDM) simulations of seismic wave propagation taking the detailed PHP model into account. It is confirmed that high-frequency guided wave energy decouple from waveguide where the shape of the PHP is suddenly deformed, which results in dramatic attenuation of high-frequency signals associating with large S-to-P conversions developed at sharp plate boundary. The present results also support the recently proposed complicated PHP-split model, however, further

  3. Dynamic nuclear polarization NMR enables the analysis of Sn-Beta zeolite prepared with natural abundance ¹¹⁹Sn precursors.

    PubMed

    Gunther, William R; Michaelis, Vladimir K; Caporini, Marc A; Griffin, Robert G; Román-Leshkov, Yuriy

    2014-04-30

    The catalytic activity of tin-containing zeolites, such as Sn-Beta, is critically dependent on the successful incorporation of the tin metal center into the zeolite framework. However, synchrotron-based techniques or solid-state nuclear magnetic resonance (ssNMR) of samples enriched with (119)Sn isotopes are the only reliable methods to verify framework incorporation. This work demonstrates, for the first time, the use of dynamic nuclear polarization (DNP) NMR for characterizing zeolites containing ~2 wt % of natural abundance Sn without the need for (119)Sn isotopic enrichment. The biradicals TOTAPOL, bTbK, bCTbK, and SPIROPOL functioned effectively as polarizing sources, and the solvent enabled proper transfer of spin polarization from the radical's unpaired electrons to the target nuclei. Using bCTbK led to an enhancement (ε) of 75, allowing the characterization of natural-abundance (119)Sn-Beta with excellent signal-to-noise ratios in <24 h. Without DNP, no (119)Sn resonances were detected after 10 days of continuous analysis. PMID:24697321

  4. Army-NASA aircrew/aircraft integration program: Phase 4 A(3)I Man-Machine Integration Design and Analysis System (MIDAS) software detailed design document

    NASA Technical Reports Server (NTRS)

    Banda, Carolyn; Bushnell, David; Chen, Scott; Chiu, Alex; Constantine, Betsy; Murray, Jerry; Neukom, Christian; Prevost, Michael; Shankar, Renuka; Staveland, Lowell

    1991-01-01

    The Man-Machine Integration Design and Analysis System (MIDAS) is an integrated suite of software components that constitutes a prototype workstation to aid designers in applying human factors principles to the design of complex human-machine systems. MIDAS is intended to be used at the very early stages of conceptual design to provide an environment wherein designers can use computational representations of the crew station and operator, instead of hardware simulators and man-in-the-loop studies, to discover problems and ask 'what if' questions regarding the projected mission, equipment, and environment. This document is the Software Product Specification for MIDAS. Introductory descriptions of the processing requirements, hardware/software environment, structure, I/O, and control are given in the main body of the document for the overall MIDAS system, with detailed discussion of the individual modules included in Annexes A-J.

  5. Assessment of phytoplankton class abundance using fluorescence excitation-emission matrix by parallel factor analysis and nonnegative least squares

    NASA Astrophysics Data System (ADS)

    Su, Rongguo; Chen, Xiaona; Wu, Zhenzhen; Yao, Peng; Shi, Xiaoyong

    2015-07-01

    The feasibility of using fluorescence excitation-emission matrix (EEM) along with parallel factor analysis (PARAFAC) and nonnegative least squares (NNLS) method for the differentiation of phytoplankton taxonomic groups was investigated. Forty-one phytoplankton species belonging to 28 genera of five divisions were studied. First, the PARAFAC model was applied to EEMs, and 15 fluorescence components were generated. Second, 15 fluorescence components were found to have a strong discriminating capability based on Bayesian discriminant analysis (BDA). Third, all spectra of the fluorescence component compositions for the 41 phytoplankton species were spectrographically sorted into 61 reference spectra using hierarchical cluster analysis (HCA), and then, the reference spectra were used to establish a database. Finally, the phytoplankton taxonomic groups was differentiated by the reference spectra database using the NNLS method. The five phytoplankton groups were differentiated with the correct discrimination ratios (CDRs) of 100% for single-species samples at the division level. The CDRs for the mixtures were above 91% for the dominant phytoplankton species and above 73% for the subdominant phytoplankton species. Sixteen of the 85 field samples collected from the Changjiang River estuary were analyzed by both HPLC-CHEMTAX and the fluorometric technique developed. The results of both methods reveal that Bacillariophyta was the dominant algal group in these 16 samples and that the subdominant algal groups comprised Dinophyta, Chlorophyta and Cryptophyta. The differentiation results by the fluorometric technique were in good agreement with those from HPLC-CHEMTAX. The results indicate that the fluorometric technique could differentiate algal taxonomic groups accurately at the division level.

  6. Lithium Abundance in Planet Search Stars

    NASA Astrophysics Data System (ADS)

    Myles, Justin; Yale Exoplanets

    2016-01-01

    Since most lithium in the universe is primordial and is destroyed in stars, lithium abundance can be used as a stellar age indicator. Some research seems to show that planet formation may also affect lithium abundance in exoplanet host stars (EHS). However, small and heterogenous samples have made both of these phenomena unclear. Further study of lithium abundance in EHS is needed to better understand possible physical roles of lithium in planet formation theory. We use a large homogenous sample with accurate stellar parameters on which we will use equivalent width analysis to determine precise lithium abundances. From these abundance values we determine an age vs. abundance relation. Additionally, we aim to explore correlation between lithium abundance and planet formation.

  7. Solar abundance of osmium

    PubMed Central

    Jacoby, George; Aller, Lawrence H.

    1976-01-01

    The abundance parameter, log gfA, where g is the statistical weight of the lower level, f is the oscillator strength, and A is the abundance (by numbers of atoms with respect to hydrogen), has been derived for three lines of osmium by a method of spectrum synthesis. An apparent discordance of the derived abundance with that found from the carbonaceous chondrites is probably to be attributed primarily to errors in the f-values, and blending with unknown contributors. PMID:16592314

  8. Identity and abundance of active sulfate-reducing bacteria in deep tidal flat sediments determined by directed cultivation and CARD-FISH analysis.

    PubMed

    Gittel, Antje; Mussmann, Marc; Sass, Henrik; Cypionka, Heribert; Könneke, Martin

    2008-10-01

    The identity and abundance of potentially active sulfate-reducing bacteria (SRB) in several metre deep sediments of a tidal sand flat in the German Wadden Sea were assessed by directed cultivation and cultivation-independent CARD-FISH analysis (catalysed reporter deposition fluorescence in situ hybridization). Presumably abundant SRB from different sediment layers between 0.5 and 4 m depth were selectively enriched in up to million-fold diluted cultures supplemented with lactate, acetate or hydrogen. Partial 16S rRNA gene sequences obtained from highest dilution steps showing sulfide formation indicated growth of deltaproteobacterial SRB belonging to the Desulfobulbaceae and the Desulfobacteraceae as well as of members of the Firmicutes. Subsequent isolation resulted in 10 novel phylotypes of both litho- and organotrophic sulfate-reducing Deltaproteobacteria. Molecular pre-screening identified six isolates as members of the Desulfobulbaceae, sharing highest identities with either candidatus 'Desulfobacterium corrodens' (95-97%) or Desulfobacterium catecholicum (98%), and four isolates as members of Desulfobacteraceae, being related to either Desulfobacter psychrotolerans (98%) or Desulfobacula phenolica (95-97%). Relatives of D. phenolica were exlusively isolated from 50 and 100 cm deep sediments with 10 and 2 mM of pore water sulfate respectively. In contrast, relatives of D. corrodens, D. psychrotolerans and D. catecholicum were also obtained from layers deeper than 100 cm and with less than 2 mM sulfate. The high in situ abundance of members of both families in sediment layers beneath 50 cm could be confirmed via CARD-FISH analysis performed with a set of six SRB-specific oligonucleotide probes. Moreover, SRB represented a numerically significant fraction of the microbial community throughout the sediment (up to 7%) and reached even higher cell numbers in deep, sulfate-poor layers than in the sulfate-rich surface sediment. This relatively large community size of

  9. Correlation of mRNA expression and protein abundance affected by multiple sequence features related to translational efficiency in Desulfovibrio vulgaris: A quantitative analysis

    SciTech Connect

    Nie, Lei; Wu, Gang; Zhang, Weiwen

    2006-12-01

    The modest correlation between mRNA expression and protein abundance in large scale datasets is explained in part by experimental challenges, such as technological limitations, and in part by fundamental biological factors in the transcription and translation processes. Among various factors affecting the mRNA-protein correlation, the roles of biological factors related to translation are poorly understood. In this study, using experimental mRNA expression and protein abundance data collected from Desulfovibrio vulgaris by DNA microarray and LC-MS/MS proteomic analysis, we quantitatively examined the effects of several translational-efficiency-related sequence features on mRNA-protein correlation. Three classes of sequence features were investigated according to different translational stages: (1) initiation: Shine-Dalgarno sequences, start codon identity and start codon context; (2) elongation: codon usage and amino acid usage; and (3) termination: stop codon identity and stop codon context. Surprisingly, although it is widely accepted that translation initiation is a rate-limiting step for translation, our results showed that the mRNA-protein correlation was affected the most by the features at elongation stages, codon usage and amino acid composition (7.4-12.6% and 5.3-9.3% of the total variation of mRNA-protein correlation, respectively), followed by stop codon context and the Shine-Dalgarno sequence (2.5-4.2% and 2.3%, respectively). Taken together, all sequence features contributed to 18.4-21.8% of the total variation of mRNA-protein correlation. As the first comprehensive quantitative analysis of the mRNA-protein correlation in bacterial D. vulgaris, our results suggest that the traditional view of the relative importance of various sequence features in prokaryotic protein translation might be questionable.

  10. What's on the menu? Assessing microbial carbon sources and cycling in soils using natural abundance radiocarbon analysis

    NASA Astrophysics Data System (ADS)

    Mahmoudi, N.; Burns, L.; Mancini, S.; Fulthorpe, R.; Slater, G. F.

    2011-12-01

    Organic matter in soils is composed of diverse materials in various stages of decomposition. Soil organic matter is not in a single pool but rather in multiple carbon pools with different intrinsic turnover times that can be on annual to decadal and even millennial timescales. Microorganisms can influence the total amount of carbon stored in soils and the turnover rates of these different pools. However, the links between microbes and their ability to utilize these various carbon pools are not well understood. Moreover, microbes have been shown to co-utilize a number of available carbon sources rather than a single carbon source under soil conditions which creates difficulties in identifying microbial carbon sources in the natural environment. Compound-specific radiocarbon analysis of microbial phospholipid fatty acids (PLFA) has become a useful tool in elucidating microbial carbon sources in complex environments with multiple carbon sources. We investigated microbial carbon cycling at an industrial site in Ontario which included a variety of carbon sources including vegetation, PAHs and natural organic matter (NOM). Using this approach, the 14C content of microbial membrane lipids (which reflects their carbon source) can be compared to surrounding carbon sources in order to assess which carbon source they are metabolizing and incorporating into their lipids. In addition, we assessed microbial community structure and diversity by analyzing amplified bacterial, eukaryotic and archaeal rDNA fragments with denaturing gel gradient electrophoresis (DGGE). The Δ14C value for PLFAs ranged from +54 to -697% which indicates that microbial carbon sources across soils differ. The Δ14CPLFA for some soils is consistent with modern carbon sources while Δ14CPLFA for other soils is consistent with natural organic matter including older pools of carbon. The microbial communities at this site are not metabolizing PAHs but rather they are utilizing various pools of natural organic

  11. Transitioning from conventional radiotherapy to intensity-modulated radiotherapy for localized prostate cancer: changing focus from rectal bleeding to detailed quality of life analysis.

    PubMed

    Yamazaki, Hideya; Nakamura, Satoaki; Nishimura, Takuya; Yoshida, Ken; Yoshioka, Yasuo; Koizumi, Masahiko; Ogawa, Kazuhiko

    2014-11-01

    With the advent of modern radiation techniques, we have been able to deliver a higher prescribed radiotherapy dose for localized prostate cancer without severe adverse reactions. We reviewed and analyzed the change of toxicity profiles of external beam radiation therapy (EBRT) from the literature. Late rectal bleeding is the main adverse effect, and an incidence of >20% of Grade ≥2 adverse events was reported for 2D conventional radiotherapy of up to 70 Gy. 3D conformal radiation therapy (3D-CRT) was found to reduce the incidence to ∼10%. Furthermore, intensity-modulated radiation therapy (IMRT) reduced it further to a few percentage points. However, simultaneously, urological toxicities were enhanced by dose escalation using highly precise external radiotherapy. We should pay more attention to detailed quality of life (QOL) analysis, not only with respect to rectal bleeding but also other specific symptoms (such as urinary incontinence and impotence), for two reasons: (i) because of the increasing number of patients aged >80 years, and (ii) because of improved survival with elevated doses of radiotherapy and/or hormonal therapy; age is an important prognostic factor not only for prostate-specific antigen (PSA) control but also for adverse reactions. Those factors shift the main focus of treatment purpose from survival and avoidance of PSA failure to maintaining good QOL, particularly in older patients. In conclusion, the focus of toxicity analysis after radiotherapy for prostate cancer patients is changing from rectal bleeding to total elaborate quality of life assessment. PMID:25204643

  12. Differential Single Nucleotide Polymorphism-Based Analysis of an Outbreak Caused by Salmonella enterica Serovar Manhattan Reveals Epidemiological Details Missed by Standard Pulsed-Field Gel Electrophoresis

    PubMed Central

    Scaltriti, Erika; Sassera, Davide; Comandatore, Francesco; Morganti, Marina; Mandalari, Carmen; Gaiarsa, Stefano; Bandi, Claudio; Zehender, Gianguglielmo; Bolzoni, Luca; Casadei, Gabriele

    2015-01-01

    We retrospectively analyzed a rare Salmonella enterica serovar Manhattan outbreak that occurred in Italy in 2009 to evaluate the potential of new genomic tools based on differential single nucleotide polymorphism (SNP) analysis in comparison with the gold standard genotyping method, pulsed-field gel electrophoresis. A total of 39 isolates were analyzed from patients (n = 15) and food, feed, animal, and environmental sources (n = 24), resulting in five different pulsed-field gel electrophoresis (PFGE) profiles. Isolates epidemiologically related to the outbreak clustered within the same pulsotype, SXB_BS.0003, without any further differentiation. Thirty-three isolates were considered for genomic analysis based on different sets of SNPs, core, synonymous, nonsynonymous, as well as SNPs in different codon positions, by Bayesian and maximum likelihood algorithms. Trees generated from core and nonsynonymous SNPs, as well as SNPs at the second and first plus second codon positions detailed four distinct groups of isolates within the outbreak pulsotype, discriminating outbreak-related isolates of human and food origins. Conversely, the trees derived from synonymous and third-codon-position SNPs clustered food and human isolates together, indicating that all outbreak-related isolates constituted a single clone, which was in line with the epidemiological evidence. Further experiments are in place to extend this approach within our regional enteropathogen surveillance system. PMID:25653407

  13. Temporal Patterns of Abundance of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) and Mitochondrial DNA Analysis of Ae. albopictus in the Central African Republic

    PubMed Central

    Kamgang, Basile; Ngoagouni, Carine; Manirakiza, Alexandre; Nakouné, Emmanuel; Paupy, Christophe; Kazanji, Mirdad

    2013-01-01

    The invasive Asian tiger mosquito Aedes albopictus (Diptera: Culicidae) was first reported in central Africa in 2000, in Cameroon, with the indigenous mosquito species Ae. aegypti (Diptera: Culicidae). Today, this invasive species is present in almost all countries of the region, including the Central African Republic (CAR), where it was first recorded in 2009. As invasive species of mosquitoes can affect the distribution of native species, resulting in new patterns of vectors and concomitant risk for disease, we undertook a comparative study early and late in the wet season in the capital and the main cities of CAR to document infestation and the ecological preferences of the two species. In addition, we determined the probable geographical origin of invasive populations of Ae. albopictus with two mitochondrial DNA genes, COI and ND5. Analysis revealed that Ae. aegypti was more abundant earlier in the wet season and Ae. albopictus in the late wet season. Used tyres were the most heavily colonized productive larval habitats for both species in both seasons. The invasive species Ae. albopictus predominated over the resident species at all sites in which the two species were sympatric. Mitochondrial DNA analysis revealed broad low genetic diversity, confirming recent introduction of Ae. albopictus in CAR. Phylogeographical analysis based on COI polymorphism indicated that the Ae. albopictus haplotype in the CAR population segregated into two lineages, suggesting multiple sources of Ae. albopictus. These data may have important implications for vector control strategies in central Africa. PMID:24349596

  14. Prognostic Importance of Gleason 7 Disease Among Patients Treated With External Beam Radiation Therapy for Prostate Cancer: Results of a Detailed Biopsy Core Analysis

    SciTech Connect

    Spratt, Daniel E.; Zumsteg, Zach; Ghadjar, Pirus; Pangasa, Misha; Pei, Xin; Fine, Samson W.; Yamada, Yoshiya; Kollmeier, Marisa; Zelefsky, Michael J.

    2013-04-01

    Purpose: To analyze the effect of primary Gleason (pG) grade among a large cohort of Gleason 7 prostate cancer patients treated with external beam radiation therapy (EBRT). Methods and Materials: From May 1989 to January 2011, 1190 Gleason 7 patients with localized prostate cancer were treated with EBRT at a single institution. Of these patients, 613 had a Gleason 7 with a minimum of a sextant biopsy with nonfragmented cores and full biopsy core details available, including number of cores of cancer involved, percentage individual core involvement, location of disease, bilaterality, and presence of perineural invasion. Median follow-up was 6 years (range, 1-16 years). The prognostic implication for the following outcomes was analyzed: biochemical recurrence-free survival (bRFS), distant metastasis-free survival (DMFS), and prostate cancer-specific mortality (PCSM). Results: The 8-year bRFS rate for pG3 versus pG4 was 77.6% versus 61.3% (P<.0001), DMFS was 96.8% versus 84.3% (P<.0001), and PCSM was 3.7% versus 8.1% (P=.002). On multivariate analysis, pG4 predicted for significantly worse outcome in all parameters. Location of disease (apex, base, mid-gland), perineural involvement, maximum individual core involvement, and the number of Gleason 3+3, 3+4, or 4+3 cores did not predict for distant metastases. Conclusions: Primary Gleason grade 4 independently predicts for worse bRFS, DMFS, and PCSM among Gleason 7 patients. Using complete core information can allow clinicians to utilize pG grade as a prognostic factor, despite not having the full pathologic details from a prostatectomy specimen. Future staging and risk grouping should investigate the incorporation of primary Gleason grade when complete biopsy core information is used.

  15. The solar abundance of Oxygen

    NASA Astrophysics Data System (ADS)

    Grevesse, N.

    2009-07-01

    With Martin Asplund (Max Planck Institute of Astrophysics, Garching) and Jacques Sauval (Observatoire Royal de Belgique, Brussels) I recently published detailed reviews on the solar chemical composition ({Asplund et al. 2005}, {Grevesse et al. 2007}). A new one, with Pat Scott (Stockholm University) as additional co-author, will appear in Annual Review of Astronomy and Astrophysics ({Asplund et al. 2009}). Here we briefly analyze recent works on the solar abundance of Oxygen and recommend a value of 8.70 in the usual astronomical scale.

  16. Capella: Structure and Abundances

    NASA Technical Reports Server (NTRS)

    Brickhouse, Nancy S.

    1999-01-01

    This grant covers the analysis of EUVE spectra of the cool star binary system Capella. This project has also required the analysis of simultaneous Advanced Satellite for Cosmology and Astrophysics (ASCA) data. The ASCA spectrum of Capella could not be fit with standard models; by imposing models based on strong lines observed with EUVE, a problem wavelength region was identified. Correcting the problem required calculations of atomic collision strengths of higher principal quantum number than had ever been calculated. With these new models applied to the ASCA spectrum, better fits were obtained. Findings are that: (1) ASCA and EUVE spectra are both dominated by a region at 6 x 10(exp 6) K. (2) The high energy cut-off of the ASCA spectrum is consistent with emission from the highest ionization stages of EUVE, namely Fe XXIV. (3) EUVE requires a continuous emission measure distribution with more than two temperatures. (4) The ASCA spectra are of such high statistical significance that systematic uncertainties dominate, including atomic physics issues and calibration issues. (5) While the ASCA spectral fits achieve lower Chi(exp 2 with two-temperature fits, the EUVE-derived emission measure distribution models are also consistent with the spectra. (6) The Fe/H ratio obtained from the ASCA fit is within 20 % of the Fe/H abundance obtained from the summed spectra of Capella over 5 EUVE pointings, as well as the 1996 EUVE data. This result confirms our claims that quasi-continua composed of weak emission lines in the short wavelength spectrometer of EUVE are not major contributors to the measured Capella continuum. Other abundance ratios are also determined from the ASCA data, using models derived with EUVE. Si, Si, and Mg appear to be close to solar photospheric values, while the ratio of Ne/Fe is three to four times lower than solar photospheric values. Whether there is a general First Ionization Potential (FIP) effect or a specific neon anomaly cannot be determined

  17. Comparing large scale CCS deployment potential in the USA and China: a detailed analysis based on country-specific CO2 transport & storage cost curves

    SciTech Connect

    Dahowski, Robert T.; Davidson, Casie L.; Dooley, James J.

    2011-04-18

    The United States and China are the two largest emitters of greenhouse gases in the world and their projected continued growth and reliance on fossil fuels, especially coal, make them strong candidates for CCS. Previous work has revealed that both nations have over 1600 large electric utility and other industrial point CO2 sources as well as very large CO2 storage resources on the order of 2,000 billion metric tons (Gt) of onshore storage capacity. In each case, the vast majority of this capacity is found in deep saline formations. In both the USA and China, candidate storage reservoirs are likely to be accessible by most sources with over 80% of these large industrial CO2 sources having a CO2 storage option within just 80 km. This suggests a strong potential for CCS deployment as a meaningful option to efforts to reduce CO2 emissions from these large, vibrant economies. However, while the USA and China possess many similarities with regards to the potential value that CCS might provide, including the range of costs at which CCS may be available to most large CO2 sources in each nation, there are a number of more subtle differences that may help us to understand the ways in which CCS deployment may differ between these two countries in order for the USA and China to work together - and in step with the rest of the world - to most efficiently reduce greenhouse gas emissions. This paper details the first ever analysis of CCS deployment costs in these two countries based on methodologically comparable CO2 source and sink inventories, economic analysis, geospatial source-sink matching and cost curve modeling. This type of analysis provides a valuable insight into the degree to which early and sustained opportunities for climate change mitigation via commercial-scale CCS are available to the two countries, and could facilitate greater collaboration in areas where those opportunities overlap.

  18. Investigating nearby star-forming galaxies in the ultraviolet with HST/COS spectroscopy. I. Spectral analysis and interstellar abundance determinations

    SciTech Connect

    James, B. L.; Aloisi, A.; Sohn, S. T.; Wolfe, M. A.; Heckman, T.

    2014-11-10

    This is the first in a series of three papers describing a project with the Cosmic Origins Spectrograph on the Hubble Space Telescope to measure abundances of the neutral interstellar medium (ISM) in a sample of nine nearby star-forming galaxies. The goal is to assess the (in)homogeneities of the multiphase ISM in galaxies where the bulk of metals can be hidden in the neutral phase, yet the metallicity is inferred from the ionized gas in the H II regions. The sample, spanning a wide range in physical properties, is to date the best suited to investigate the metallicity behavior of the neutral gas at redshift z = 0. ISM absorption lines were detected against the far-ultraviolet spectra of the brightest star-forming region(s) within each galaxy. Here we report on the observations, data reduction, and analysis of these spectra. Column densities were measured by a multicomponent line-profile fitting technique, and neutral-gas abundances were obtained for a wide range of elements. Several caveats were considered, including line saturation, ionization corrections, and dust depletion. Ionization effects were quantified with ad hoc CLOUDY models reproducing the complex photoionization structure of the ionized and neutral gas surrounding the UV-bright sources. An 'average spectrum of a redshift z = 0 star-forming galaxy' was obtained from the average column densities of unsaturated profiles of neutral-gas species. This template can be used as a powerful tool for studies of the neutral ISM at both low and high redshift.

  19. Detailed seal analysis, Lower Cretaceous rocks of the North Sinai basin, Egypt: Effects on hydrocarbon migration and accumulation in overpressured regimes

    SciTech Connect

    Nashaat, M. )

    1991-03-01

    The filling mechanism of petroleum traps in the North Sinai basin has been studied, taking into account the area's maturation history, the hydrodynamic parameters, and the seal efficiencies. The purpose of this study was to ascertain whether or not sizeable accumulations of hydrocarbons could be expected and to investigate the origin of the oil discovered to date. Formation pressure regimes in the North Sinai basin include highly overpressured reservoirs with undercompacted shale, starting at relatively shallow depths. In particular, the deeper closed hydraulic systems usually exhibit abnormally pressured regimes in individual fluid compartments. The pressure regimes are separated from each other by seals that are of particular interest to explorationists, as they frequently support oil and gas pools. The fracture pressures as well as the formation pore pressures were used together in some wells to evaluate seal quality. This detailed seal analysis has identified many regional seals and pressure compartments and their lateral and areal extent. These seals seem to control the hydrodynamic regime in the underlying permeable Lower Cretaceous reservoirs, and along with source maturation strongly affect the migration of hydrocarbons from source rocks and their accumulation in reservoirs. The water chemistry of the undercompacted sediments and overpressured reservoirs agrees with the different hydrodynamic systems mapped. Water chemistry zones clearly define different hydraulic systems. Originally, they are the freshwater aquifer of Lower Cretaceous overlain by higher salinity formations.

  20. Definition of the locus responsible for systemic carnitine deficiency within a 1.6-cM region of mouse chromosome 11 by detailed linkage analysis

    SciTech Connect

    Okita, Kohei; Tokino, Takashi; Nishimori, Hiroyuki

    1996-04-15

    Carnitine is an essential cofactor for oxidation of mitochondrial fatty acids. Carnitine deficiency results in failure of energy production by mitochondria and leads to metabolic encephalopathy, lipid-storage myopathy, and cardiomyopathy. The juvenile visceral steatosis (JVS) mouse, an animal model of systemic carnitine deficiency, inherits the JVS phenotype in autosomal recessive fashion, through a mutant allele mapped to mouse chromosome 11. As a step toward identifying the gene responsible for JVS by positional cloning, we attempted to refine the jvs locus in the mouse by detailed linkage analysis with 13 microsatellite markers, using 190 backcross progeny. Among the 13 loci tested, 5 (defined by markers D11Mit24, D11Mit111,D11Nds9, D11Mit86, and D11Mit23) showed no recombination, with a maximum lod score of 52.38. Our results implied that the jvs gene can be sought on mouse chromosome 11 within a genetic distance no greater than about 1.6 cM. 21 refs., 2 figs.

  1. Facing Challenges for Monte Carlo Analysis of Full PWR Cores : Towards Optimal Detail Level for Coupled Neutronics and Proper Diffusion Data for Nodal Kinetics

    NASA Astrophysics Data System (ADS)

    Nuttin, A.; Capellan, N.; David, S.; Doligez, X.; El Mhari, C.; Méplan, O.

    2014-06-01

    Safety analysis of innovative reactor designs requires three dimensional modeling to ensure a sufficiently realistic description, starting from steady state. Actual Monte Carlo (MC) neutron transport codes are suitable candidates to simulate large complex geometries, with eventual innovative fuel. But if local values such as power densities over small regions are needed, reliable results get more difficult to obtain within an acceptable computation time. In this scope, NEA has proposed a performance test of full PWR core calculations based on Monte Carlo neutron transport, which we have used to define an optimal detail level for convergence of steady state coupled neutronics. Coupling between MCNP for neutronics and the subchannel code COBRA for thermal-hydraulics has been performed using the C++ tool MURE, developed for about ten years at LPSC and IPNO. In parallel with this study and within the same MURE framework, a simplified code of nodal kinetics based on two-group and few-point diffusion equations has been developed and validated on a typical CANDU LOCA. Methods for the computation of necessary diffusion data have been defined and applied to NU (Nat. U) and Th fuel CANDU after assembly evolutions by MURE. Simplicity of CANDU LOCA model has made possible a comparison of these two fuel behaviours during such a transient.

  2. Revealing Structural Details of SiCO Ceramics with GIPAW Calculations of Model Structures and Analysis of Experimental 29Si Nuclear Magnetic Resonance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Nimmo, John; Kroll, Peter

    2015-03-01

    The occurrence of the various SiCxO4-x (1 <=x <=4) mixed tetrahedra in silicon oxycarbide (SiCO) is often quantified by means of experimental 29Si nuclear magnetic resonance. The structural centers are assigned to individual peaks in the spectrum, which can be integrated to give the relative populations. Using a recently-developed method, we show that is is also possible to recover information on the connectivity of these tetrahedra. By combining a huge library of model structures an GIPAW calculations, we show that simple relations exist between the Si-O-Si linking angles and the 29Si NMR chemical shift. In this work, we perform detailed analyses of SiCO 29Si NMR spectra available in literature. We extract angular distributions in agreement with the experimental X-ray and neutron diffraction data. Furthermore, in glasses with large amounts of so-called ``free'' carbon, we observe a significant portion of the {Si}O4 tetrahedra which have disproportionately large angles. These angles indicate the presence of internal SiO2 surfaces or cages-like voids, similar to those found in zeolites or clathrates. This analysis suggests that in SiCO, the ``free'' carbon is incorporated into these voids, which produces strain on the bonding angles of the surrounding host glass.

  3. Characterizing accuracy of total hemoglobin recovery using contrast-detail analysis in 3D image-guided near infrared spectroscopy with the boundary element method

    PubMed Central

    Ghadyani, Hamid R.; Srinivasan, Subhadra; Pogue, Brian W.; Paulsen, Keith D.

    2010-01-01

    The quantification of total hemoglobin concentration (HbT) obtained from multi-modality image-guided near infrared spectroscopy (IG-NIRS) was characterized using the boundary element method (BEM) for 3D image reconstruction. Multi-modality IG-NIRS systems use a priori information to guide the reconstruction process. While this has been shown to improve resolution, the effect on quantitative accuracy is unclear. Here, through systematic contrast-detail analysis, the fidelity of IG-NIRS in quantifying HbT was examined using 3D simulations. These simulations show that HbT could be recovered for medium sized (20mm in 100mm total diameter) spherical inclusions with an average error of 15%, for the physiologically relevant situation of 2:1 or higher contrast between background and inclusion. Using partial 3D volume meshes to reduce the ill-posed nature of the image reconstruction, inclusions as small as 14mm could be accurately quantified with less than 15% error, for contrasts of 1.5 or higher. This suggests that 3D IG-NIRS provides quantitatively accurate results for sizes seen early in treatment cycle of patients undergoing neoadjuvant chemotherapy when the tumors are larger than 30mm. PMID:20720975

  4. Surface abundances of light elements for a large sample of early B-type stars - III. An analysis of helium lines in spectra of 102 stars

    NASA Astrophysics Data System (ADS)

    Lyubimkov, L. S.; Rostopchin, S. I.; Lambert, D. L.

    2004-06-01

    Non-local thermodynamic equilibrium analysis of He I lines in spectra of 102 B stars is implemented in order to derive the helium abundance He/H, the microturbulent parameter Vt and the projected rotation velocity v sini. A simultaneous determination of He/H and Vt for the stars is effected by analysing equivalent widths of the 4471- and 4922-Å lines primarily as indicators of He/H and the 4713-, 5016-, 5876- and 6678-Å lines primarily as indicators of Vt. The rotation velocities v sini are found from profiles of the same lines. It is shown that, when Vt > 7 km s-1, the Vt(He I) values determined from He I lines are systematically overestimated as compared with the Vt(OII, NII) values derived from OII and NII lines. This discrepancy is especially appreciable for hot evolved B giants with Vt(He I) = 16-23 km s-1 and may indicate a failure of classical model atmospheres to represent the strong He I lines for these stars. Two programme stars, HR 1512 and 7651, are found to be helium-weak stars. The remaining 100 stars are divided into three groups according to their masses M. The microturbulent parameter Vt(He I) is low for all stars of group A (M= 4.1-6.9 Msolar) and for all stars with the relative ages t/tMS < 0.8 of group B (M= 7.0-11.2 Msolar). Their Vt(He I) values are within the 0 to 5 km s-1 range, as a rule; the mean value is Vt= 1.7 km s-1. Only evolved giants of group B, which are close to the termination of the main-sequence (MS) evolutionary phase (t/tMS > 0.8), show Vt(He I) up to 11 km s-1. The helium abundance He/H is correlated with the relative age t/tMS in both groups; the averaged He/H enhancement during the MS phase is 26 per cent. For group C, containing the most massive stars (M= 12.4-18.8 Msolar), the Vt(He I) values display a correlation with t/tMS, varying from 4 to 23 km s-1. The He/H determination for hot evolved B giants of the group with Vt(He I) > 15 km s-1 depends on a choice between the Vt(He I) and Vt(OII, NII) scales. The mean He

  5. Detailed Analysis of the Solution Heat Treatment of a Third-Generation Single-Crystal Nickel-Based Superalloy CMSX-10K®

    NASA Astrophysics Data System (ADS)

    Pang, Hon Tong; D'Souza, Neil; Dong, Hongbiao; Stone, Howard J.; Rae, Catherine M. F.

    2016-02-01

    A detailed analysis of the response of as-cast third-generation single-crystal nickel-based superalloy CMSX-10K® to solution heat treatment (SHT) has been carried out, alongside an SHT optimization exercise. The analysis was conducted through microstructural characterization, differential scanning calorimetry, and compositional homogeneity measurements, quantifying (i) the dissolution and microstructural evolution of the inter-dendritic constituents, (ii) the shift in thermo-physical characteristics of the material, and (iii) the change in compositional homogeneity across the microstructure, in order to gain further understanding of these phenomena during the progression of the SHT. During the early stages of SHT, the coarse cellular γ'/narrow γ channel inter-dendritic constituents which were the last areas to solidify during casting, progressively dissolve; homogenization between these inter-dendritic areas and adjacent dendritic areas leads to a rapid increase in the incipient melting temperature T IM. The fine γ/γ' morphology which were the first inter-dendritic constituents to solidify after primary γ dendrite solidification were found to progressively coarsen; however, subsequent dissolution of these coarsened γ/γ' inter-dendritic areas did not result in significant increases in the T IM until the near-complete dissolution of these inter-dendritic areas. After the final SHT step, residual compositional micro-segregation could still be detected across the microstructure despite the near-complete dissolution of these remnant inter-dendritic areas; even so the T IM of the material approached the solidus temperature of the alloy.

  6. Coronal abundances and their variation

    NASA Technical Reports Server (NTRS)

    Saba, Julia L. R.

    1994-01-01

    This contract supports the investigation of elemental abundances in the solar corona, principally through analysis of high-resolution software X-ray spectra from the Flat Crystal Spectrometer on NASA's Solar Maximum Mission. The goals of the study are a characterization of the mean values of relative abundances of elements accessible in the FCS data, and information on the extent and circumstances of their variability. This report is a summation of the data analysis and reporting activities which occurred since the last report, submitted two months early, in April 1994, to facilitate evaluation of the first year's progress for contract renewal. Hence this report covers the period 15 April 1994 - 15 December 1994. A list of publications resulting from this research is included.

  7. First Stellar Abundances in the Dwarf Irregular Galaxy IC 1613

    NASA Astrophysics Data System (ADS)

    Tautvaišienė, Gražina; Geisler, Doug; Wallerstein, George; Borissova, Jura; Bizyaev, Dmitry; Pagel, Bernard E. J.; Charbonnel, Corinne; Smith, Verne

    2007-12-01

    Chemical abundances in three M supergiants in the Local Group dwarf irregular galaxy IC 1613 have been determined using high-resolution spectra obtained with the UVES spectrograph on the ESO 8.2 m Kueyen telescope. A detailed synthetic-spectrum analysis has been used to determine the atmospheric parameters and abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, Cr, Fe, Co, Ni, La, and Eu. We find the overall metallicity of the stars to be [Fe/H] = -0.67 ± 0.09 and the age 9-13 Myr, which is in excellent agreement with the present-day values in the age-metallicity relationship model of IC 1613 by Skillman et al. We have found that the three supergiants investigated have a mean [α/Fe] equal to about -0.1, which is lower than seen in Galactic stars at the same metallicity and is in agreement with the results obtained in other dwarf irregular galaxies. The oxygen abundances are in agreement with the upper values of the nebular oxygen determinations in IC 1613. The abundance ratios of s- and r-process elements to iron are enhanced relative to solar by about 0.3 dex. The abundance pattern of the elements studied is similar to that of the Small Magellanic Cloud, except for Co and Ni, which are underabundant in the SMC. The observed elemental abundances are generally in very good agreement with the recent chemical evolution model of Yuk and Lee. Based on observations collected with the Very Large Telescope and the 2.2 m Telescope of the European Southern Observatory within the Observing Programs 70.B-0361(A) and 072.D-0113(D).

  8. Chemical Compositions and Abundance Anomalies in Stellar Coronae ADP 99

    NASA Technical Reports Server (NTRS)

    Drake, Jeremy; Oliversen, Ronald J. (Technical Monitor)

    2003-01-01

    Progress has been made using both EUVE (Extreme Ultraviolet Explorer) and ASCA (Advanced Satellite for Cosmology and Astrophysics) data and a new postdoctoral scientist has now been hired. Stars studied to date include YY Gem (dMe binary), xi Boo A (intermediate activity G8 V), xi UMa (more active G quadruple system) HR1099 (K1 IV + G5 V) RS CVn-like, AU Mic (dMe). In addition to a paper that concentrated on abundancies in HR1099, a paper was recently submitted on the coronal abundances of AR(tilde)Lac that revealed an interesting pattern of overabundances of very low FIP elements (Al and Ca) compared to the low FIP elements Si, Mg and Fe. Two papers are nearing completion on methods of analysis and on the abundances in the corona of AU(tilde)Mic. Additionally, two invited conference proceedings papers are being published on this work. The main conclusion of the study to date is that our existing ideas of coronal abundance anomalies need complete revision. The solar-like FIP effect is replaced by a pattern than appears to enhance high FIP elements rather than low FIP elements in very active stars. The archival studies we are undertaking now are revealing some key details of these patterns, and are beginning to map out the anomalies as a function of spectral type, a key goal of this study.

  9. Detail One Half of Wood Truss, Detail One Quarter Plan ...

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

    Detail One Half of Wood Truss, Detail One Quarter Plan of Floor Beams & Bottom Truss Cord, Detail at A Plan, Detail at B Plan - Covered Bridge, Spanning Darby Creek, North Lewisburg, Champaign County, OH

  10. Chord Splicing & Joining Detail; Chord & CrossBracing Joint Details; ...

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

    Chord Splicing & Joining Detail; Chord & Cross-Bracing Joint Details; Cross Bracing Center Joint Detail; Chord & Diagonal Joint Detail - Vermont Covered Bridge, Highland Park, spanning Kokomo Creek at West end of Deffenbaugh Street (moved to), Kokomo, Howard County, IN

  11. Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, ...

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

    Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, Panel Post, Tie & Diagonal Brace Joint Detail; Chord, Panel Post, Tie & Crossbracing Joint Detail - Dunlapsville Covered Bridge, Spanning East Fork Whitewater River, Dunlapsville, Union County, IN

  12. Gaia FGK benchmark stars: abundances of α and iron-peak elements

    NASA Astrophysics Data System (ADS)

    Jofré, P.; Heiter, U.; Soubiran, C.; Blanco-Cuaresma, S.; Masseron, T.; Nordlander, T.; Chemin, L.; Worley, C. C.; Van Eck, S.; Hourihane, A.; Gilmore, G.; Adibekyan, V.; Bergemann, M.; Cantat-Gaudin, T.; Delgado-Mena, E.; González Hernández, J. I.; Guiglion, G.; Lardo, C.; de Laverny, P.; Lind, K.; Magrini, L.; Mikolaitis, S.; Montes, D.; Pancino, E.; Recio-Blanco, A.; Sordo, R.; Sousa, S.; Tabernero, H. M.; Vallenari, A.

    2015-10-01

    Context. In the current era of large spectroscopic surveys of the Milky Way, reference stars for calibrating astrophysical parameters and chemical abundances are of paramount importance. Aims: We determine elemental abundances of Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni for our predefined set of Gaia FGK benchmark stars. Methods: By analysing high-resolution spectra with a high signal-to-noise ratio taken from several archive datasets, we combined results of eight different methods to determine abundances on a line-by-line basis. We performed a detailed homogeneous analysis of the systematic uncertainties, such as differential versus absolute abundance analysis. We also assessed errors that are due to non-local thermal equilibrium and the stellar parameters in our final abundances. Results: Our results are provided by listing final abundances and the different sources of uncertainties, as well as line-by-line and method-by-method abundances. Conclusions: The atmospheric parameters of the Gaia FGK benchmark stars are already being widely used for calibration of several pipelines that are applied to different surveys. With the added reference abundances of ten elements, this set is very suitable for calibrating the chemical abundances obtained by these pipelines. Based on NARVAL and HARPS data obtained within the Gaia DPAC (Data Processing and Analysis Consortium) and coordinated by the GBOG (Ground-Based Observations for Gaia) working group and on data retrieved from the ESO-ADP database.Tables C.1-C.35 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/582/A81

  13. Position-Specific Isotope Analysis of Xanthines: A (13)C Nuclear Magnetic Resonance Method to Determine the (13)C Intramolecular Composition at Natural Abundance.

    PubMed

    Diomande, Didier G; Martineau, Estelle; Gilbert, Alexis; Nun, Pierrick; Murata, Ariaki; Yamada, Keita; Watanabe, Naoharu; Tea, Illa; Robins, Richard J; Yoshida, Naohiro; Remaud, Gérald S

    2015-07-01

    The natural xanthines caffeine, theobromine, and theophylline are of major commercial importance as flavor constituents in coffee, cocoa, tea, and a number of other beverages. However, their exploitation for authenticity, a requirement in these commodities that have a large origin-based price-range, by the standard method of isotope ratio monitoring by mass spectrometry (irm-MS) is limited. We have now developed a methodology that overcomes this deficit that exploits the power of isotopic quantitative (13)C nuclear magnetic resonance (NMR) spectrometry combined with chemical modification of the xanthines to enable the determination of positional intramolecular (13)C/(12)C ratios (δ(13)Ci) with high precision. However, only caffeine is amenable to analysis: theobromine and theophylline present substantial difficulties due to their poor solubility. However, their N-methylation to caffeine makes spectral acquisition feasible. The method is confirmed as robust, with good repeatability of the δ(13)Ci values in caffeine appropriate for isotope fractionation measurements at natural abundance. It is shown that there is negligible isotope fractionation during the chemical N-methylation procedure. Thus, the method preserves the original positional δ(13)Ci values. The method has been applied to measure the position-specific variation of the (13)C/(12)C distribution in caffeine. Not only is a clear difference between caffeine isolated from different sources observed, but theobromine from cocoa is found to show a (13)C pattern distinct from that of caffeine. PMID:26067163

  14. Identification of Putative Genes Involved in Bisphenol A Degradation Using Differential Protein Abundance Analysis of Sphingobium sp. BiD32.

    PubMed

    Zhou, Nicolette A; Kjeldal, Henrik; Gough, Heidi L; Nielsen, Jeppe L

    2015-10-20

    Discharge of the endocrine disrupting compound bisphenol A (BPA) with wastewater treatment plant (WWTP) effluents into surface waters results in deleterious effects on aquatic life. Sphingobium sp. BiD32 was previously isolated from activated sludge based on its ability to degrade BPA. This study investigated BPA metabolism by Sphingobium sp. BiD32 using label-free quantitative proteomics. The genome of Sphingobium sp. BiD32 was sequenced to provide a species-specific platform for optimal protein identification. The bacterial proteomes of Sphingobium sp. BiD32 in the presence and absence of BPA were identified and quantified. A total of 2155 proteins were identified; 1174 of these proteins were quantified, and 184 of these proteins had a statistically significant change in abundance in response to the presence/absence of BPA (p ≤ 0.05). Proteins encoded by genes previously identified to be responsible for protocatechuate degradation were upregulated in the presence of BPA. The analysis of the metabolites from BPA degradation by Sphingobium sp. BiD32 detected a hydroxylated metabolite. A novel p-hydroxybenzoate hydroxylase enzyme detected by proteomics was implicated in the metabolic pathway associated with the detected metabolite. This enzyme is hypothesized to be involved in BPA degradation by Sphingobium sp. BiD32, and may serve as a future genetic marker for BPA degradation. PMID:26390302

  15. Uses of Phage Display in Agriculture: Sequence Analysis and Comparative Modeling of Late Embryogenesis Abundant Client Proteins Suggest Protein-Nucleic Acid Binding Functionality

    PubMed Central

    Kushwaha, Rekha; Downie, A. Bruce; Payne, Christina M.

    2013-01-01

    A group of intrinsically disordered, hydrophilic proteins—Late Embryogenesis Abundant (LEA) proteins—has been linked to survival in plants and animals in periods of stress, putatively through safeguarding enzymatic function and prevention of aggregation in times of dehydration/heat. Yet despite decades of effort, the molecular-level mechanisms defining this protective function remain unknown. A recent effort to understand LEA functionality began with the unique application of phage display, wherein phage display and biopanning over recombinant Seed Maturation Protein homologs from Arabidopsis thaliana and Glycine max were used to retrieve client proteins at two different temperatures, with one intended to represent heat stress. From this previous study, we identified 21 client proteins for which clones were recovered, sometimes repeatedly. Here, we use sequence analysis and homology modeling of the client proteins to ascertain common sequence and structural properties that may contribute to binding affinity with the protective LEA protein. Our methods uncover what appears to be a predilection for protein-nucleic acid interactions among LEA client proteins, which is suggestive of subcellular residence. The results from this initial computational study will guide future efforts to uncover the protein protective mechanisms during heat stress, potentially leading to phage-display-directed evolution of synthetic LEA molecules. PMID:23956788

  16. Semi-quantitative analysis of solid waste flows from nano-enabled consumer products in Europe, Denmark and the United Kingdom - Abundance, distribution and management.

    PubMed

    Heggelund, Laura; Hansen, Steffen Foss; Astrup, Thomas Fruergaard; Boldrin, Alessio

    2016-10-01

    Many nano-enabled consumer products are known to be in the global market. At the same, little is known about the quantity, type, location etc. of the engineered nanomaterials (ENMs) inside the products. This limits the scientific investigations of potential environmental effects of these materials, and especially the knowledge of ENM behaviour and potential effects at the end-of-life stage of the products is scarce. To gain a better understanding of the end-of-life waste treatment of nano-enabled consumer product, we provide an overview of the ENMs flowing into and throughout waste systems in Europe, Denmark and the United Kingdom. Using a nanoproduct inventory (nanodb.dk), we performed a four-step analysis to estimate the most abundant ENMs and in which waste fractions they are present. We found that in terms of number of products: (i) nano silver is the most used ENM in consumer products, and (ii) plastic from used product containers is the largest waste fraction also comprising a large variety of ENMs, though possibly in very small masses. Also, we showed that the local waste management system can influence the distribution of ENMs. It is recommended that future research focus on recycling and landfilling of nano-enabled products since these compartments represent hot spots for end-of-life nanoproducts. PMID:27311351

  17. Abundance Gradients in Clusters of Galaxies

    NASA Astrophysics Data System (ADS)

    Dupke, Renato De Alencar

    This dissertation presents the analysis of spatially resolved ASCA satellite X-ray spectra for four clusters of galaxies (Abell 496, Abell 2199, Abell 3571 and Abell 1060). The abundance distributions of Abell 496, Abell 2199 and Abell 3571 are shown to be centrally enhanced. The distribution of elemental abundance ratios, combined with calculations of supernovae rates, shows that the central abundance enhancement in these galaxy clusters is dominated by supernova, Type 1a iron, while the outer parts are dominated by supernovae Type II iron and the most likely mechanism proposed to produce this central iron is ram-pressure stripping, rather than accumulated stellar mass loss from the central dominant galaxy. At least 50% (by mass) of the iron in the central regions is from supernovae Type Ia, varying slightly from cluster to cluster. Although the analysis of Abell 1060 reveals no significant central abundance enhancement, supernovae Type Ia are shown to contribute significantly to the iron content of the central regions. However, accumulated stellar mass loss from the two central dominant galaxies in this cluster can account for all of the supernovae Type la iron in the central regions. The nickel to iron abundance ratio shows that delayed detonation explosion models for supernovae Type la are inconsistent with the observed abundance ratios in the inner regions of Abell 496, Abell 2199 and Abell 3571. A comparison of the distributions of iron mass and the luminosity of early type galaxies in four clusters, three of them having central abundance enhancements (Virgo, Abell 496 and Centaurus) and one having a flat abundance distribution (Coma), indicates that the iron mass traces the luminosity of early type galaxies in abundance gradient clusters better than in flat abundance clusters. This suggests that abundance gradients can be washed out by cluster mergers.

  18. LF460 detail design

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This is the final technical report documenting the detail design of the LF460, and advanced turbotip lift fan intended for application with the YJ97-GE-100 turbojet jet generator to a V/STOL transport research aircraft. Primary objective of the design was to achieve a low noise level while maintaining the high thrust/weight ratio capability of a high pressure ratio lift fan. Report covers design requirements and summarizes activities and final results in the areas of aerodynamic and mechanical design, component and system performance, acoustic features and final noise predictions.

  19. Details of meiosis

    SciTech Connect

    1993-12-31

    Chapter 18, discusses the details of meiosis, beginning with the structure and number of chiasmata, i.e., the cytological term for two homologous chromosomes forming a bivalent which begin to repel each other until they are held together only at the point of crossing-over. The synaptonemal complex which consists of two lateral elements which contain protein and RNA is also discussed. The chapter concludes with a description of meiosis in polyploids, human meiosis, and the behavior of X and Y chromosomes. 28 refs., 8 figs.

  20. Success! Detailed Pre-event Analysis Identified the Slip Area and Magnitude of the Sept. 2012 MW 7.6 Nicoya Earthquake

    NASA Astrophysics Data System (ADS)

    Newman, A. V.; Protti, M.; Gonzalez, V. M.; Dixon, T. H.; Schwartz, S. Y.; Feng, L.; Peng, Z.; Marshall, J.; Malservisi, R.; Owen, S. E.

    2013-05-01

    On September 5th, 2012 a moment magnitude (MW) 7.6 earthquake struck the seismogenic megathrust of Nicoya Costa Rica. Though, we knew not precisely when, this event was not unexpected, and occurred after the development of substantial pre-event scientific discovery and earthquake infrastructural development. Beginning in the late- 1990's Nicoya Costa Rica was recognized by the U.S. National Science Foundation -MARGINS program as a focus area for seismogenic zone studies in part because of the unique proximity of land to the active subduction megathrust. The region also has very fast convergence (~9 cm/a) and has suffered from regular M7+ earthquakes in 1853, 1900 and 1950. Another similar event was expected by many. Pre-event analysis identified the structure of the subduction interface [Newman et al., GRL, 2002; DeShon et al., GJI, 2006], the location and rate changes of ongoing microseismicity [Newman et al., GRL, 2002, Ghosh et al.,GRL, 2008], the location and degree of locking that developed during the late interseismic [Norabuena et al., JGR, 2006; Feng et al., JGR, 2012], and its relation to ongoing low-frequency earthquakes, subduction tremor, and episodic slip events [Walter et al., GRL, 2011; Outerbridge et al., JGR, 2010, Jiang et al., G3, 2012]. Feng et al., [2012] using campaign and continuous GPS data through 2012, identified complex locked 50x50 km patch along the central coast of Nicoya, the locale that failed in Sept 2012, and concluded that the region had the potential to fail in an MW 7.8 event should the most recent locking be representative of behavior since the last major event in 1950. In operation at the time of the event was a substantial NSF-funded continuous GPS (17 station) and seismic (18 station) network maintained by USF, UCSC, and GIT, in cooperation with OVSICORI. The seismic network captured the initial motions of the mainshock before clipping, as well as pre-shock and aftershock activity [Walter et al., (this meeting), 2013]. The

  1. Solar abundance of platinum

    PubMed Central

    Burger, Harry; Aller, Lawrence H.

    1975-01-01

    Three lines of neutral platinum, located at λ 2997.98 Å, λ 3064.71 Å, and λ 3301.86 Å have been used to determine the solar platinum abundance by the method of spectral synthesis. On the scale, log A(H) = 12.00, the thus-derived solar platinum abundance is 1.75 ± 0.10, in fair accord with Cameron's value of log A(Pt) = 1.69 derived by Mason from carbonaceous chondrites and calculated on the assumption that log A(Si) = 7.55 in the sun. PMID:16592278

  2. Uterine smooth muscle tumors with features suggesting fumarate hydratase aberration: detailed morphologic analysis and correlation with S-(2-succino)-cysteine immunohistochemistry

    PubMed Central

    Reyes, Carolina; Karamurzin, Yevgeniy; Frizzell, Norma; Garg, Karuna; Nonaka, Daisuke; Chen, Ying-Bei; Soslow, Robert A.

    2013-01-01

    Rare, sporadic uterine leiomyomas arise in the setting of severe metabolic aberration due to somatic fumarate hydratase mutation. Germline mutations account for the Hereditary Leiomyomatosis and Renal Cell Carcinoma syndrome, which predisposes for cutaneous and uterine leiomyomas and aggressive renal cell carcinomas. Altered fumarate hydratase leads to fumarate accumulates in affected cells with formation of S-(2-succino)-cysteine, which can be detected with polyclonal antibody. High levels of these modified cysteine residues are found characteristically in fumarate hydratase-deficient cells, but not in normal tissues or tumors unassociated with Hereditary Leiomyomatosis and Renal Cell Carcinoma syndrome. We hypothesized that S-(2-succino)-cysteine-positive leiomyomas, indicating fumarate hydratase aberration, have morphologic features that differ from those without S-(2-succino)-cysteine positivity. Hematoxylin and eosin-stained slides of uterine smooth muscle tumors were prospectively analyzed for features suggesting Hereditary Leiomyomatosis and Renal Cell Carcinoma Syndrome, such as prominent eosinophilic macronucleoli with perinucleolar halos, yielding 9 cases. Germline genetic testing for fumarate hydratase mutations was performed in 3 cases. A detailed morphological analysis was undertaken, and S-(2-succino)-cysteine immunohistochemistry was performed with controls from a tissue microarray [leiomyomas (19), leiomyosarcomas (29), and endometrial stromal tumors (15)]. Of the 9 study cases, 4 had multiple uterine smooth muscle tumors. All cases had increased cellularity, staghorn vasculature, and fibrillary cytoplasm with pink globules. All cases had inclusion-like nucleoli with perinuclear halos (7 diffuse, 1 focal). All showed diffuse granular cytoplasmic labeling with the S-(2-succino)-cysteine antibody. Two of 3 tested patients had germline fumarate hydratase mutations. Only 1 leiomyoma from the tissue microarray controls was immunohistochemically positive

  3. Numerical resolution limits on subhalo abundance matching

    NASA Astrophysics Data System (ADS)

    Guo, Qi; White, Simon

    2014-02-01

    Subhalo abundance matching (SHAM) inserts galaxies into dark matter only simulations of the growth of cosmic structure in a way that requires minimal assumptions about galaxy formation. A galaxy is placed at the potential minimum of each distinct self-bound subhalo with a luminosity which is a monotonically increasing function of the maximum mass (or circular velocity) attained over the subhalo's earlier history. Galaxy and subhalo properties are linked by matching model and observed luminosity functions. Simulated structures can then be compared in detail with observation, for example, through galaxy correlation statistics, group catalogues or galaxy-galaxy lensing. Robust astrophysical conclusions can be drawn from such a comparison only on scales which are unaffected by the numerical limitations of the simulation. Here, we compare results for the Millennium Simulation (MS) with subhaloes defined using the SUBFIND to those obtained applying identical analysis to the much higher resolution Millennium-II. Correlation statistics on scales between 200 and 2 Mpc converge to within 20 per cent only for subhaloes with masses at infall corresponding to at least 1000 simulation particles in the MS. Numerically converged results can be obtained to much lower infall particle number, if galaxies are followed even after their associated subhaloes have been tidally disrupted, as in most recent semi-analytic galaxy formation simulations. This allows robust comparison between simulation and observation over a wider dynamic range in mass than for a SHAM analysis which ignores such `orphan' galaxies.

  4. Detail of Triton

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This color photo of Neptune's large satellite Triton was obtained on Aug. 24 1989 at a range of 530,000 kilometers (330,000 miles). The resolution is about 10 kilometers (6.2 miles), sufficient to begin to show topographic detail. The image was made from pictures taken through the green, violet and ultraviolet filters. In this technique, regions that are highly reflective in the ultraviolet appear blue in color. In reality, there is no part of Triton that would appear blue to the eye. The bright southern hemisphere of Triton, which fills most of this frame, is generally pink in tone as is the even brighter equatorial band. The darker regions north of the equator also tend to be pink or reddish in color. JPL manages the Voyager project for NASA's Office of Space Science, Washington, DC.

  5. Cydonia Region - detail

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Detail cut out of PIA01235, Mars Orbiter Camera (MOC) image of a 4.42 by 82.94 km area of the Cydonia Region. The left image is raw, the right has been filtered and contrast enhanced.

    Orbit: 220

    Range: 444.21 km

    Resolution: 4.32 m/pixel

    Emission angle: 44.66 degrees

    Incidence angle: 64.96 degrees

    Phase angle: 61.97 degrees

    Scan rate: 0.1 degree/sec

    Start time: periapsis + 375 sec

    Sequence submitted to JPL: Sat 04/04/98 15:15 PST

    Image acquired by MOC: Sun 04/05/98 00:39:37 PST

    Data retrieved from JPL: Mon 04/06/98 09:05 PDT

  6. South Polar Details

    NASA Technical Reports Server (NTRS)

    2005-01-01

    22 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows details among some of the eroded layer outcrops of the martian south polar region. Much of the south polar region of Mars is covered by a thick unit of layered material. For decades, the layers have been assumed to consist of a mixture of dust and ice, but it is equally possible that the materials are sedimentary rocks. This image was captured during southern spring, at a time when some of the surface was still covered by seasonal carbon dioxide (CO2) frost.

    Location near: 86.5oS, 116.6oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  7. 16S rDNA analysis of archaea indicates dominance of Methanobacterium and high abundance of Methanomassiliicoccaceae in rumen of Nili-Ravi buffalo.

    PubMed

    Paul, S S; Deb, S M; Dey, A; Somvanshi, S P S; Singh, D; Rathore, R; Stiverson, J

    2015-10-01

    The molecular diversity of rumen methanogens was investigated using 16S rDNA gene library prepared from the rumen contents of Nili-Ravi buffaloes. Microbial genomic DNA was isolated from four adult male fistulated buffaloes and PCR conditions were set up using specific primers. Amplified product was cloned into a suitable vector, and the inserts of positive clones were sequenced. A total of 142 clones were examined, and the analysis revealed 46 species level (0.01 distance) operational taxonomic units (OTUs). Twenty six OTUs comprising 89 clones (63% of the total clones) were taxonomically assigned to Methanobacterium genus and the majority of them had highest percent identity with Methanobacterium flexile among cultured methanogens. Five OTUs comprising 27 clones (19% of total clones) were taxonomically assigned to Methanomicrobium genus and these clones showed highest sequence identity with Methanomicrobium mobile. Only two OTUs comprising 6 clones (4% of total clones) were assigned to Methanobrevibacter genus. A total of 17 clones belonging to 10 species level OTUs showed highest percent identity (ranging from 85 to 95%) with Methanomassilicoccus luminyensis and were taxonomically classified as Methanomassiliicocaceae. Out of the 142 rDNA clones, 112 clones, which constitute 79% of the total clones representing 42 OTUs, had less than 98.5% sequence identity with any of the cultured strains of methanogens and represent novel species of methanogens. This study has revealed the largest assortment of hydrogenotrophic methanogen phylotypes ever identified from the rumen of Nili-Ravi buffaloes. The study indicates that Methanobacterium is the most dominant methanogen in the rumen of Nili-Ravi buffalo. This is also the first report on the presence of methanogens phylogenetically close to M. luminyensis, an H2 dependent methylotrophic methanogen, in the rumen of buffaloes at such a high level of abundance. PMID:26103451

  8. Abundances of light elements.

    PubMed Central

    Pagel, B E

    1993-01-01

    Recent developments in the study of abundances of light elements and their relevance to cosmological nucleosynthesis are briefly reviewed. The simplest model, based on standard cosmology and particle physics and assuming homogeneous baryon density at the relevant times, continues to stand up well. PMID:11607388

  9. Elemental Abundances in NGC 3516

    NASA Technical Reports Server (NTRS)

    Turner, T. J.; Kraemer, S. B.; Mushotzky, R. F.; George, I. M.; Gabel, J. R.

    2003-01-01

    We present Reflection Grating Spectrometer data from an XMM-Newton observation of the Seyfert 1 galaxy NGC 3516, taken while the continuum source was in an extremely low flux state. This observation offers a rare opportunity for a detailed study of emission from a Seyfert 1 galaxy as these are usually dominated by high nuclear continuum levels and heavy absorption. The spectrum shows numerous narrow emission lines (FWHM approximately less than 1300 kilometers per second) in the 0.3 - 2 keV range, including the H-like lines of C, N, and O and the He-like lines of N, O and Ne. The emission-line ratios and the narrow width of the radiative recombination continuum of CVI indicate that the gas is photoionized and of fairly low temperature (kT approximately less than 0.01 keV). The availability of emission lines from different elements for two iso-electronic sequences allows us to constrain the element abundances. These data show that the N lines are far stronger than would be expected from gas of solar abundances. Based on our photoionization models we find that nitrogen is overabundant in the central regions of the galaxy, compared to carbon, oxygen and neon by at least a factor of 2.5. We suggest that this is the result of secondary production of nitrogen in intermediate mass stars, and indicative of the history of star formation in NGC 3516.

  10. Electrophoretic separation of in vitro translation products on giant two-dimensional gels allows detailed analysis of cellular mRNAs

    SciTech Connect

    Colbert, R.A.; Young, D.A.

    1986-11-05

    The in vitro translation products of mRNA pretreated with methylmercuric hydroxide were examined by giant two-dimensional gel electrophoresis. In addition to increasing overall translational efficiency approximately 2.5-fold, methylmercuric hydroxide selectively increases the translation of mRNAs coding for higher molecular mass (greater than 45 kDa) proteins, allowing the routine resolution of 1500 (35S)methionine-labeled proteins. This yields 3 to 4-fold the number of translation products seen with smaller size two-dimensional gels. With this method we compare thymus cell proteins synthesized in vivo with the products of in vitro translation of mRNA recovered from thymus cells. Fifty-eight percent of the translation products are qualitatively the same as proteins synthesized in vivo (similar Mr, pI, and neighboring proteins), with 64% of these also being quantitatively similar (less than 5-fold difference). A comparison of thymus mRNA in vitro translation products with those coded for by mRNA from liver reveals only 32% qualitative similarity, with 63% of these also being quantitatively similar. These results are discussed in relation to predictions of mRNA abundance and complexity based on DNA:RNA hybridization data. Giant two-dimensional gel separations of in vitro translation products appear to be useful for detecting less abundant cellular mRNAs, including those that may be regulated by hormones or other physiological mediators.

  11. Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

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

    Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Joint, Vertical Cross Bracing End Detail - Ceylon Covered Bridge, Limberlost Park, spanning Wabash River at County Road 900 South, Geneva, Adams County, IN

  12. Surface abundances of OC supergiants

    NASA Astrophysics Data System (ADS)

    Martins, F.; Foschino, S.; Bouret, J.-C.; Barbá, R.; Howarth, I.

    2016-04-01

    Context. Some O and B stars show unusually strong or weak lines of carbon and/or nitrogen. These objects are classified as OBN or OBC stars. It has recently been shown that nitrogen enrichment and carbon depletion are the most likely explanations for the existence of the ON class. Aims: We investigate OC stars (all being supergiants) to check that surface abundances are responsible for the observed anomalous line strengths. Methods: We perform a spectroscopic analysis of three OC supergiants using atmosphere models. A fourth star was previously studied by us. Our sample thus comprises all OC stars known to date in the Galaxy. We determine the stellar parameters and He, C, N, and O surface abundances. Results: We show that all stars have effective temperatures and surface gravities fully consistent with morphologically normal O supergiants. However, OC stars show little, if any, nitrogen enrichment and carbon surface abundances consistent with the initial composition. OC supergiants are thus barely chemically evolved, unlike morphologically normal O supergiants. Based on observations obtained at the ESO/La Silla Observatory under programs 081.D-2008, 083.D-0589, 089.D-0975.

  13. Crowdsourcing detailed flood data

    NASA Astrophysics Data System (ADS)

    Walliman, Nicholas; Ogden, Ray; Amouzad*, Shahrzhad

    2015-04-01

    Over the last decade the average annual loss across the European Union due to flooding has been 4.5bn Euros, but increasingly intense rainfall, as well as population growth, urbanisation and the rising costs of asset replacements, may see this rise to 23bn Euros a year by 2050. Equally disturbing are the profound social costs to individuals, families and communities which in addition to loss of lives include: loss of livelihoods, decreased purchasing and production power, relocation and migration, adverse psychosocial effects, and hindrance of economic growth and development. Flood prediction, management and defence strategies rely on the availability of accurate information and flood modelling. Whilst automated data gathering (by measurement and satellite) of the extent of flooding is already advanced it is least reliable in urban and physically complex geographies where often the need for precise estimation is most acute. Crowdsourced data of actual flood events is a potentially critical component of this allowing improved accuracy in situations and identifying the effects of local landscape and topography where the height of a simple kerb, or discontinuity in a boundary wall can have profound importance. Mobile 'App' based data acquisition using crowdsourcing in critical areas can combine camera records with GPS positional data and time, as well as descriptive data relating to the event. This will automatically produce a dataset, managed in ArcView GIS, with the potential for follow up calls to get more information through structured scripts for each strand. Through this local residents can provide highly detailed information that can be reflected in sophisticated flood protection models and be core to framing urban resilience strategies and optimising the effectiveness of investment. This paper will describe this pioneering approach that will develop flood event data in support of systems that will advance existing approaches such as developed in the in the UK

  14. roof truss detail, historic strap hinge detail Chopawamsic Recreational ...

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

    roof truss detail, historic strap hinge detail - Chopawamsic Recreational Demonstration Area - Cabin Camp 1, Main Arts and Crafts Lodge, Prince William Forest Park, Triangle, Prince William County, VA

  15. double hung window details, hall window details, entrance door profiles ...

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

    double hung window details, hall window details, entrance door profiles - Chopawamsic Recreational Demonstration Area - Cabin Camp 1, Help's Quarters, Prince William Forest Park, Triangle, Prince William County, VA

  16. Detailed mechanism of benzene oxidation

    NASA Technical Reports Server (NTRS)

    Bittker, David A.

    1987-01-01

    A detailed quantitative mechanism for the oxidation of benzene in both argon and nitrogen diluted systems is presented. Computed ignition delay time for argon diluted mixtures are in satisfactory agreement with experimental results for a wide range of initial conditions. An experimental temperature versus time profile for a nitrogen diluted oxidation was accurately matched and several concentration profiles were matched qualitatively. Application of sensitivity analysis has given approximate rate constant expressions for the two dominant heat release reactions, the oxidation of C6H5 and C5H5 radicals by molecular oxygen.

  17. "Influence Method". Detailed mathematical description

    NASA Astrophysics Data System (ADS)

    Rios, I. J.; Mayer, R. E.

    2015-07-01

    A new method for the absolute determination of nuclear particle flux in the absence of known detector efficiency, the "Influence Method", was recently published (I.J. Rios and R.E. Mayer, Nuclear Instruments & Methods in Physics Research A 775 (2015) 99-104). The method defines an estimator for the population and another estimator for the efficiency. In this article we present a detailed mathematical description which yields the conditions for its application, the probability distributions of the estimators and their characteristic parameters. An analysis of the different cases leads to expressions of the estimators and their uncertainties.

  18. The Abundance of Interstellar Fluorine

    NASA Technical Reports Server (NTRS)

    Lauroesch, James T.

    2005-01-01

    The primary objective of this program was to obtain FUSE observations of the interstellar absorption lines of F I at 951 and 954 Angstroms to derive the abundance of fluorine toward the star HD 164816. The nucleosynthetic source(s) of fluorine are still a matter of debate - the present day abundance of fluorine can potentially constrain models for pulsationally driven dredge-up in asymptotic giant branch stars. An accurate measure for the depletion behavior of fluorine will determine whether it may be detectable in QSO absorption line systems - an unambiguous detection of fluorine at suitably high redshifts would provide the best evidence to date for the neutrino process in massive stars. Furthermore, due to its extreme reactivity, measurement of the gas-phase interstellar fluorine abundance is important for models of grain chemistry. Despite the importance of measuring the interstellar fluorine abundance, at the time of our proposal only one previous detection has been made due to the low relative abundance of fluorine, the lack of lines outside the far-UV, and the blending of the available F I transitions with lines of Hz. The star HD 164816 is associated with the Lagoon nebula (M8), and at a distance of approximately 1.5 kpc probes both distant and local gas. Beginning April 8th, 2004 FUSE FP-Split observations of the star HD 164816 were obtained for this program. This data became available in the FUSE data archive May 21, 2004, and these observations were then downloaded and we began our analysis. Our analysis procedure has involved (1) fitting stellar models to the FUSE spectra, (2) using the multiple lines of Hz and N I at other wavelengths in the FUSE bandpass to derive column densities for the lines of H2 and N I which are blended with the F I features at 951 and 954 angstroms (3) the measurement of the column densities of F I and the species O I and C1 I which are important species for the dis-entangling of dust and nucleosynthetic effects. As discussed in

  19. Element abundances of classical novae

    NASA Astrophysics Data System (ADS)

    Andrea, J.; Drechsel, H.; Starrfield, S.

    1994-11-01

    Physical conditions and element abundances in the optically thin shells of 11 classical novae with outbursts between 1978 and 1989 were determined from an analysis of UV and optical spectra obtained during the nebular stage. Eight novae were studied on the basis of new optical and UV spectra. The accuracy of the element abundances depends on whether or not simultaneous UV spectra were available to determine individual ionization stage dependent gas temperatures. Generally, slightly higher than solar abundances of helium and pronounced overabundances of the heavier elements were found. QU Vul turned out to be an ONeMg nova, while the other objects belong to the class of CO novae. The nature of V2214 Oph could not be completely clarified. The novae V1668 Cyg (1978), V693 CrA (1981), and V1370 Aql (1982), for which published element abundances exist, were reanalyzed to check the consistency of our spectral analysis approach. Satisfactory agreement of the results was found. Photoionization calculations were carried out for PW Vul using the code of Aldrovandi, Pequignot, and Stasinska. A synthetic spectrum was generated for the parameters derived from the analysis of the UV and optical spectra, which is in very good agreement with the observations. The spectral analysis technique was then applied to the model spectrum and reproduced the model parameters well. Electron temperatures for the C(2+) and C(3+) ions between 7 500 and 12,000 K and for N(4+) betwen 12,000 and 16,000 K were derived. For PW Vul these temperatures remained relatively constant over several months. The decline in density of the ejected shells with time could be investigated for V842 Cen, QV Vul, V977 Sco, and V443 Sct, and was found to deviate from the relation Ne proportional to t-2 for free expansion of a shell in a different way for each object. A possible explanation may be the complex density structure of the shells. This suspicion is supported by high resolution spectra (ESO 3.6m telescope

  20. Abundance measurements in stellar environments

    NASA Astrophysics Data System (ADS)

    Leone, F.

    2014-05-01

    Most of what we know about stars, and systems of stars, is derived from the analysis of their electromagnetic radiation. This lesson is an attempt to describe to Physicists, without any Astrophysical background, the framework to understand the present status of abundance determination in stellar environments and its limit. These notes are dedicated to the recently passed, November 21, 2013, Prof. Dimitri Mihalas who spent his life confuting the 19th century positivist philosopher Auguste Comte who stated that we shall not at all be able to determine the chemical composition of stars.

  1. Abundance measurements in stellar environments

    SciTech Connect

    Leone, F.

    2014-05-09

    Most of what we know about stars, and systems of stars, is derived from the analysis of their electromagnetic radiation. This lesson is an attempt to describe to Physicists, without any Astrophysical background, the framework to understand the present status of abundance determination in stellar environments and its limit. These notes are dedicated to the recently passed, November 21, 2013, Prof. Dimitri Mihalas who spent his life confuting the 19th century positivist philosopher Auguste Comte who stated that we shall not at all be able to determine the chemical composition of stars.

  2. Solar abundances and 3D model atmospheres

    NASA Astrophysics Data System (ADS)

    Ludwig, Hans-Günter; Caffau, Elisabetta; Steffen, Matthias; Bonifacio, Piercarlo; Freytag, Bernd; Cayrel, Roger

    2010-03-01

    We present solar photospheric abundances for 12 elements from optical and near-infrared spectroscopy. The abundance analysis was conducted employing 3D hydrodynamical (CO5BOLD) as well as standard 1D hydrostatic model atmospheres. We compare our results to others with emphasis on discrepancies and still lingering problems, in particular exemplified by the pivotal abundance of oxygen. We argue that the thermal structure of the lower solar photosphere is very well represented by our 3D model. We obtain an excellent match of the observed center-to-limb variation of the line-blanketed continuum intensity, also at wavelengths shortward of the Balmer jump.

  3. Survey and Down-Selection of Acid Gas Removal Systems for the Thermochemical Conversion of Biomass to Ethanol with a Detailed Analysis of an MDEA System

    SciTech Connect

    Nexant, Inc., San Francisco, California

    2011-05-01

    The first section (Task 1) of this report by Nexant includes a survey and screening of various acid gas removal processes in order to evaluate their capability to meet the specific design requirements for thermochemical ethanol synthesis in NREL's thermochemical ethanol design report (Phillips et al. 2007, NREL/TP-510-41168). MDEA and selexol were short-listed as the most promising acid-gas removal agents based on work described in Task 1. The second report section (Task 2) describes a detailed design of an MDEA (methyl diethanol amine) based acid gas removal system for removing CO2 and H2S from biomass-derived syngas. Only MDEA was chosen for detailed study because of the available resources.

  4. Solar abundance of iridium

    PubMed Central

    Drake, Stephen; Aller, Lawrence H.

    1976-01-01

    By a method of spectrum synthesis, which yields log gfA, where g is the statistical weight of the lower level, f is the oscillator strength, and A is the abundance, an attempt is made to deduce the solar iridium abundance from one relatively unblended, but fairly weak IrI line, λ 3220.78 Å. If the Corliss-Bozman f-value for this line is adopted, we find log A(Ir) = 0.82 on the scale log A(H) = 12.00. The discordance with the value found from carbonaceous chondrites may arise from faulty f-values or from difficulties arising from line blending in this far ultraviolet domain of the solar spectrum. PMID:16578735

  5. Spectroscopic measurements of element abundances in the solar corona: Variations on the FIP theme

    NASA Technical Reports Server (NTRS)

    Saba, J. L. R.

    1995-01-01

    Solar wind and solar energetic particle (SEP) data yield systematic differences between elemental abundances in the corona and in the photosphere related to the first ionization potential (FIP) of the elements: low-FIP elements are preferentially enhanced relative to high-FIP elements by about a factor of four. Spectroscopic studies of the inner corona show that such a pattern may apply on average but not in detail for coronal loops: substantial abundance differences occur between different types of coronal structures, and variations have been found from flare to flare, from one active region to another, and over time in the same region; further, in some flares, anomalies such as enhanced Ne:O ratios, distinctly at odds with the FIP pattern, show that a competing element selection mechanism sometimes operates. Details of the observed abundance variability -- such as the magnitude of the variations, the relevant temporal and spatial scales, and correlations with other properties of the given coronal structure -- may give important clues to the processes which supply and heat the corona, or they may reflect the changing physical conditions or locations where those processes take place. However, many such details remain to be established definitively. At present, abundance variability is primarily a major complication to data analysis and interpretation. However, once it is better understood, it may provide a new diagnostic tool for probing the lower layers of the solar atmosphere.

  6. PHYTOPLANKTON SPECIES COMPOSITION, ABUNDANCE AND DISTRIBUTION IN SOUTHERN LAKE HURON, 1980, INCLUDING A COMPARATIVE ANALYSIS WITH CONDITIONS IN 1974 PRIOR TO NUTRIENT LOADING REDUCTIONS

    EPA Science Inventory

    This summarizes studies conducted during 1980 to assess the effects of reductions in phosphorus loading to Saginaw Bay on phytoplankton in the bay and the adjacent waters of Lake Huron. Quantitative estimates of phytoplankton abundance were developed from an array of stations sam...

  7. Kinematics and chemical abundances of the B star HD 28248

    NASA Astrophysics Data System (ADS)

    Levenhagen, R. S.; Künzel, R.; Leister, N. V.

    2013-07-01

    We perform a detailed elemental abundance study of the early-type B star HD 28248 and estimate its orbital path in the Galaxy. From the comparison of spectroscopic observations performed at the European Southern Observatory at La Silla in 2001/Oct/07 with non-LTE synthetic spectra using a new wrapper for the simultaneous fitting of several lines of a given atomic species, the abundances of He, C, N, O, Mg, Al, Si, P, S, Ar and Fe were determined for the first time. The radial velocity of HD 28248 has been also estimated from the positions of centroids of nine neutral helium lines and Mg IIλ 4481 Å, allowing to calculate its right-handed Galactic space-velocity components U,V and W and estimate its orbital path in the Galaxy for the first time. Our chemical analysis depicted an outstanding enrichment of several atomic species, particularly [Fe/H] = +0.25 dex and [O/Fe] = +0.32 dex. The kinematic parameters show that its orbit is confined to the galactic disk with a scale height of 400 pc and the star has moved about 4 kpc from its birthplace to the current position. The elemental abundances do not follow the predicted [Fe/H] and [O/Fe] gradients currently established for the Galaxy. A hypothetical scenario for the contamination could be the mass transfer in a binary system during previous evolutionary phases.

  8. ASPCAP: The APOGEE Stellar Parameter and Chemical Abundances Pipeline

    NASA Astrophysics Data System (ADS)

    García Pérez, Ana E.; Allende Prieto, Carlos; Holtzman, Jon A.; Shetrone, Matthew; Mészáros, Szabolcs; Bizyaev, Dmitry; Carrera, Ricardo; Cunha, Katia; García-Hernández, D. A.; Johnson, Jennifer A.; Majewski, Steven R.; Nidever, David L.; Schiavon, Ricardo P.; Shane, Neville; Smith, Verne V.; Sobeck, Jennifer; Troup, Nicholas; Zamora, Olga; Weinberg, David H.; Bovy, Jo; Eisenstein, Daniel J.; Feuillet, Diane; Frinchaboy, Peter M.; Hayden, Michael R.; Hearty, Fred R.; Nguyen, Duy C.; O’Connell, Robert W.; Pinsonneault, Marc H.; Wilson, John C.; Zasowski, Gail

    2016-06-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has built the largest moderately high-resolution (R ≈ 22,500) spectroscopic map of the stars across the Milky Way, and including dust-obscured areas. The APOGEE Stellar Parameter and Chemical Abundances Pipeline (ASPCAP) is the software developed for the automated analysis of these spectra. ASPCAP determines atmospheric parameters and chemical abundances from observed spectra by comparing observed spectra to libraries of theoretical spectra, using χ2 minimization in a multidimensional parameter space. The package consists of a fortran90 code that does the actual minimization and a wrapper IDL code for book-keeping and data handling. This paper explains in detail the ASPCAP components and functionality, and presents results from a number of tests designed to check its performance. ASPCAP provides stellar effective temperatures, surface gravities, and metallicities precise to 2%, 0.1 dex, and 0.05 dex, respectively, for most APOGEE stars, which are predominantly giants. It also provides abundances for up to 15 chemical elements with various levels of precision, typically under 0.1 dex. The final data release (DR12) of the Sloan Digital Sky Survey III contains an APOGEE database of more than 150,000 stars. ASPCAP development continues in the SDSS-IV APOGEE-2 survey.

  9. Abundances of r-PROCESS Elements in the Photosphere of Red Supergiant Star PMMR23 in Small Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Vasil'Eva, S. V.; Gopka, V. F.; Yushchenko, A. V.; Andryevsky, S. M.

    Detailed analysis of chemical abundances determined from high-resolution CCD-spectrogram of supergiant star PMMR23 (K5 I) in SMC is presented. The observation were obtained at 3.6 meter ESO La Silla telescope by Hill (1997). Spectral resolving power is near R=30.000. The wavelength coverage is 5050-7200 A. The abundances of iron and 15 r-, s-processes elements are found. The abundances of Cu, Zr, Mo, Ru, Pr, Sm, Gd, Dy, Er are found for the first time. The abundances of elements with atomic numbers less than 55 are deficient with respect to the Sun. The mean underabundance is near 0.7 dex. The abundances of barium and lanthanides are near solar values. The overabundances of these elements with respect to iron are in the range from 0.4 tp 0.9 dex. The abundances of heavy lanthanides are higher than the abundances of light lanthanides. The abundance pattern of PMMR23 can be fitted by scaled solar r-process distribution. The atmosphere of PMMR23 is enriched by r-process elements.

  10. DETAILED ANALYSIS OF SOA ORIGINATING FROM THE PHOTOOXIDATION OF D-LIMONENE IN THE PRESENCE OF NO X AND UV LIGHT AND ITS IMPLICATION TO AMBIENT PM 2.5

    EPA Science Inventory

    A detailed analysis was carried out of the aerosol phase originated from the photooxidation of d-limonene in the presence of NOx and artificial light with the analytical emphasis on the identification of oxygenated organic compounds. The major components included six ...

  11. DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR

    SciTech Connect

    BYRNES ME, KALMAR JA

    2007-11-26

    This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.

  12. Elemental Abundance Analyses with DAO Spectrograms. XXXIX. The Am Stars 2 UMa and 15 Vul

    NASA Astrophysics Data System (ADS)

    Çay, İpek H.; Teker Yelkenci, Aysegul; Adelman, Saul J.

    2016-05-01

    We derived the elemental abundances of the metallic-line stars 2 UMa (=HR 3354; spectral type A2m) and 15 Vul (=HR 7653; spectral type A4 III), using high-dispersion, high signal-to-noise ratio (≥200) optical region spectrograms obtained with CCD detectors at the long Coudé camera of the 1.22 m telescope of the Dominion Astrophysical Observatory (DAO) and Kurucz's ATLAS9 and WIDTH9 programs. The star 2 UMa has not been the subject of a modern detailed elemental abundances analysis. It is relatively sharp-lined and sufficiently hot (T eff = 8050 K) that the continuum placement is not a major problem in the optical region. Comparison of the results of this new study of 15 Vul with the last complete study shows a 0.15 dex mean increase in the derived abundances and a reduction in the standard deviations of the mean values. The abundance anomalies of 2 UMa are usually larger than those of 15 Vul. The greater spectral coverage of 15 Vul compared with 2 UMa results in a larger number of abundances being derived. The abundances of 2 UMa are typical for those of classical Am stars that have similar effective temperatures and surface gravities. 15 Vul, characterized by a similar effective temperature and smaller surface gravity, is a more evolved star.

  13. The Abundances of Neutron-capture Species in the Very Metal-poor Globular Cluster M15: A Uniform Analysis of Red Giant Branch and Red Horizontal Branch Stars

    NASA Astrophysics Data System (ADS)

    Sobeck, Jennifer S.; Kraft, Robert P.; Sneden, Christopher; Preston, George W.; Cowan, John J.; Smith, Graeme H.; Thompson, Ian B.; Shectman, Stephen A.; Burley, Gregory S.

    2011-06-01

    The globular cluster M15 is unique in its display of star-to-star variations in the neutron-capture elements. Comprehensive abundance surveys have been previously conducted for handfuls of M15 red giant branch (RGB) and red horizontal branch (RHB) stars. No attempt has been made to perform a single, self-consistent analysis of these stars, which exhibit a wide range in atmospheric parameters. In the current effort, a new comparative abundance derivation is presented for three RGB and six RHB members of the cluster. The analysis employs an updated version of the line transfer code MOOG, which now appropriately treats coherent, isotropic scattering. The apparent discrepancy in the previously reported values for the metallicity of M15 RGB and RHB stars is addressed and a resolute disparity of Δ(RHB - RGB) ≈ 0.1 dex in the iron abundance was found. The anti-correlative behavior of the light neutron-capture elements (Sr, Y, Zr) is clearly demonstrated with both Ba and Eu, standard markers of the s- and r-process, respectively. No conclusive detection of Pb was made in the RGB targets. Consequently for the M15 cluster, this suggests that the main component of the s-process has made a negligible contribution to those elements normally dominated by this process in solar system material. Additionally for the M15 sample, a large Eu abundance spread is confirmed, which is comparable to that of the halo field at the same metallicity. These abundance results are considered in the discussion of the chemical inhomogeneity and nucleosynthetic history of M15.

  14. Abundance of field galaxies

    NASA Astrophysics Data System (ADS)

    Klypin, Anatoly; Karachentsev, Igor; Makarov, Dmitry; Nasonova, Olga

    2015-12-01

    We present new measurements of the abundance of galaxies with a given circular velocity in the Local Volume: a region centred on the Milky Way Galaxy and extending to distance ˜10 Mpc. The sample of ˜750 mostly dwarf galaxies provides a unique opportunity to study the abundance and properties of galaxies down to absolute magnitudes MB ≈ -10 and virial masses M_vir= 109{ M_{⊙}}. We find that the standard Λ cold dark matter (ΛCDM) model gives remarkably accurate estimates for the velocity function of galaxies with circular velocities V ≳ 70 kms-1 and corresponding virial masses M_vir≳ 5× 10^{10}{ M_{⊙}}, but it badly fails by overpredicting ˜5 times the abundance of large dwarfs with velocities V = 30-40 kms-1. The warm dark matter (WDM) models cannot explain the data either, regardless of mass of WDM particle. Just as in previous observational studies, we find a shallow asymptotic slope dN/dlog V ∝ Vα, α ≈ -1 of the velocity function, which is inconsistent with the standard ΛCDM model that predicts the slope α = -3. Though reminiscent to the known overabundance of satellite problem, the overabundance of field galaxies is a much more difficult problem. For the standard ΛCDM model to survive, in the 10 Mpc radius of the Milky Way there should be 1000 not yet detected galaxies with virial mass M_vir≈ 10^{10}{ M_{⊙}}, extremely low surface brightness and no detectable H I gas. So far none of this type of galaxies have been discovered.

  15. Late embryogenesis abundant proteins

    PubMed Central

    Olvera-Carrillo, Yadira; Reyes, José Luis

    2011-01-01

    Late Embryogenesis Abundant (LEA) proteins accumulate at the onset of seed desiccation and in response to water deficit in vegetative plant tissues. The typical LEA proteins are highly hydrophilic and intrinsically unstructured. They have been classified in different families, each one showing distinctive conserved motifs. In this manuscript we present and discuss some of the recent findings regarding their role in plant adaptation to water deficit, as well as those concerning to their possible function, and how it can be related to their intrinsic structural flexibility. PMID:21447997

  16. Photospheric abundances of oxygen, neon, and argon derived from the XUV spectrum of an impulsive flare

    SciTech Connect

    Feldman, U.; Widing, K.G. )

    1990-11-01

    Relative elemental abundances of O, Ne, Na, Mg, Ar, and Ca are determined from detailed analysis of XUV spectra emitted by an impulsive flare. The electron density measured from three diagnostic line ratios is 2-3 x 10 to the 12th/cu cm. It was found that the relative abundances in the flare are similar to values obtained from or proposed for photospheric material. The ratios of O/Mg, Ne/Mg, and Ar/Mg are about four times higher in the impulsive flare than the values typically observed in the average corona. It is suggested that electric fields above the photosphere may be responsible for the order of magnitude variations between the abundances of the group of elements with high first ionization potentials (FIP) and the group with low FIP. 18 refs.

  17. Solar abundances from gamma-ray spectroscopy - Comparisons with energetic particle, photospheric, and coronal abundances

    NASA Technical Reports Server (NTRS)

    Murphy, R. J.; Ramaty, R.; Reames, D. V.; Kozlovsky, B.

    1991-01-01

    Accelerated particle and ambient gas abundances have been derived using solar flare gamma-ray spectroscopy. The results with photospheric and coronal abundances, as well as with solar energetic particle abundances. This is the first time that the composition of accelerated particles interacting in an astrophysical source has been compared with the composition of particles escaping from the source. The analysis shows that the derived composition of the accelerated particles is different from the composition of particles observed in large proton flares; rather, it resembles the composition observed in He-3-rich flares. The analysis also suggests an ambient gas composition which differs from the composition of both the photosphere and the corona.

  18. Temporal variations of aerosol, glyoxal, and formaldehyde at urban sites of Japan as observed by MAX-DOAS based on detailed error analysis

    NASA Astrophysics Data System (ADS)

    Irie, H.; Chin, S.; Ni, W.; Nakayama, T.; Shimizu, A.; Yamazaki, A.; Nagai, T.; Takamura, T.; Khatri, P.

    2014-12-01

    The degradation of volatile organic compounds (VOCs) results in the formation of ozone (O3) and secondary organic aerosols (SOA) in the troposphere. This process consists of the oxidation of VOCs by hydroxyl radical (OH), O3, and nitrate radical (NO3). Detailed understanding of the VOC degradation mechanism is challenged by the co-existence of vast variety of VOC species in the atmosphere. However, investigations on ubiquitous oxidation intermediates, e.g., formaldehyde (HCHO) and glyoxal (CHOCHO), can help us improve the current knowledge of the VOC sources and degradation pathways. We installed one ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) system in Meteorological Research Institute (MRI) located at Tsukuba, Japan (36.06N, 130.13E) in June 2010. In addition, two more systems were installed in Chiba University at Chiba, Japan (35.63N, 140.10E) in June and December 2012, respectively. Since then, we have retrieved lower-tropospheric vertical profile information for eight components; aerosol extinction coefficients at two wavelengths, 357 and 476 nm, and NO2, HCHO, CHOCHO, H2O, SO2, and O3 concentrations. For a detailed evaluation for the aerosol retrieval, which is a key step in the MAX-DOAS eight-component retrieval, simultaneous aerosol observations with the Cavity Ring-Down Spectroscopy (CRDS), lidar, and sky radiometer were conducted at Tsukuba on October 5-18, 2010. At Chiba, in addition to the comparison with sky radiometer data, a self-consistency test was performed by comparing results obtained from two MAX-DOAS systems operated at the same place. Through these detailed evaluations, our retrieval method was improved significantly, attaining excellent agreement with CRDS, lidar, and sky radiometer data. On the basis of these efforts, we find clear seasonal and diurnal temporal variations in HCHO and CHOCHO concentrations and their ratios (RGF) retrieved from MAX-DOAS systems. Using NO2 retrieved together with HCHO and

  19. Detailed analysis of metagenome datasets obtained from biogas-producing microbial communities residing in biogas reactors does not indicate the presence of putative pathogenic microorganisms

    PubMed Central

    2013-01-01

    Background In recent years biogas plants in Germany have been supposed to be involved in amplification and dissemination of pathogenic bacteria causing severe infections in humans and animals. In particular, biogas plants are discussed to contribute to the spreading of Escherichia coli infections in humans or chronic botulism in cattle caused by Clostridium botulinum. Metagenome datasets of microbial communities from an agricultural biogas plant as well as from anaerobic lab-scale digesters operating at different temperatures and conditions were analyzed for the presence of putative pathogenic bacteria and virulence determinants by various bioinformatic approaches. Results All datasets featured a low abundance of reads that were taxonomically assigned to the genus Escherichia or further selected genera comprising pathogenic species. Higher numbers of reads were taxonomically assigned to the genus Clostridium. However, only very few sequences were predicted to originate from pathogenic clostridial species. Moreover, mapping of metagenome reads to complete genome sequences of selected pathogenic bacteria revealed that not the pathogenic species itself, but only species that are more or less related to pathogenic ones are present in the fermentation samples analyzed. Likewise, known virulence determinants could hardly be detected. Only a marginal number of reads showed similarity to sequences described in the Microbial Virulence Database MvirDB such as those encoding protein toxins, virulence proteins or antibiotic resistance determinants. Conclusions Findings of this first study of metagenomic sequence reads of biogas producing microbial communities suggest that the risk of dissemination of pathogenic bacteria by application of digestates from biogas fermentations as fertilizers is low, because obtained results do not indicate the presence of putative pathogenic microorganisms in the samples analyzed. PMID:23557021

  20. Predicting the dynamics of protein abundance.

    PubMed

    Mehdi, Ahmed M; Patrick, Ralph; Bailey, Timothy L; Bodén, Mikael

    2014-05-01

    Protein synthesis is finely regulated across all organisms, from bacteria to humans, and its integrity underpins many important processes. Emerging evidence suggests that the dynamic range of protein abundance is greater than that observed at the transcript level. Technological breakthroughs now mean that sequencing-based measurement of mRNA levels is routine, but protocols for measuring protein abundance remain both complex and expensive. This paper introduces a Bayesian network that integrates transcriptomic and proteomic data to predict protein abundance and to model the effects of its determinants. We aim to use this model to follow a molecular response over time, from condition-specific data, in order to understand adaptation during processes such as the cell cycle. With microarray data now available for many conditions, the general utility of a protein abundance predictor is broad. Whereas most quantitative proteomics studies have focused on higher organisms, we developed a predictive model of protein abundance for both Saccharomyces cerevisiae and Schizosaccharomyces pombe to explore the latitude at the protein level. Our predictor primarily relies on mRNA level, mRNA-protein interaction, mRNA folding energy and half-life, and tRNA adaptation. The combination of key features, allowing for the low certainty and uneven coverage of experimental observations, gives comparatively minor but robust prediction accuracy. The model substantially improved the analysis of protein regulation during the cell cycle: predicted protein abundance identified twice as many cell-cycle-associated proteins as experimental mRNA levels. Predicted protein abundance was more dynamic than observed mRNA expression, agreeing with experimental protein abundance from a human cell line. We illustrate how the same model can be used to predict the folding energy of mRNA when protein abundance is available, lending credence to the emerging view that mRNA folding affects translation efficiency

  1. Predicting the Dynamics of Protein Abundance

    PubMed Central

    Mehdi, Ahmed M.; Patrick, Ralph; Bailey, Timothy L.; Bodén, Mikael

    2014-01-01

    Protein synthesis is finely regulated across all organisms, from bacteria to humans, and its integrity underpins many important processes. Emerging evidence suggests that the dynamic range of protein abundance is greater than that observed at the transcript level. Technological breakthroughs now mean that sequencing-based measurement of mRNA levels is routine, but protocols for measuring protein abundance remain both complex and expensive. This paper introduces a Bayesian network that integrates transcriptomic and proteomic data to predict protein abundance and to model the effects of its determinants. We aim to use this model to follow a molecular response over time, from condition-specific data, in order to understand adaptation during processes such as the cell cycle. With microarray data now available for many conditions, the general utility of a protein abundance predictor is broad. Whereas most quantitative proteomics studies have focused on higher organisms, we developed a predictive model of protein abundance for both Saccharomyces cerevisiae and Schizosaccharomyces pombe to explore the latitude at the protein level. Our predictor primarily relies on mRNA level, mRNA–protein interaction, mRNA folding energy and half-life, and tRNA adaptation. The combination of key features, allowing for the low certainty and uneven coverage of experimental observations, gives comparatively minor but robust prediction accuracy. The model substantially improved the analysis of protein regulation during the cell cycle: predicted protein abundance identified twice as many cell-cycle-associated proteins as experimental mRNA levels. Predicted protein abundance was more dynamic than observed mRNA expression, agreeing with experimental protein abundance from a human cell line. We illustrate how the same model can be used to predict the folding energy of mRNA when protein abundance is available, lending credence to the emerging view that mRNA folding affects translation

  2. Detailed analysis of minimum operation voltage of extraordinarily unstable cells in fully depleted silicon-on-buried-oxide six-transistor static random access memory

    NASA Astrophysics Data System (ADS)

    Mizutani, Tomoko; Yamamoto, Yoshiki; Makiyama, Hideki; Yamashita, Tomohiro; Oda, Hidekazu; Kamohara, Shiro; Sugii, Nobuyuki; Hiramoto, Toshiro

    2015-04-01

    The minimum operation voltage (Vmin) of very unstable cells in silicon-on-thin-buried-oxide (SOTB) six-transistor (6T) static random access memory (SRAM) is analyzed in detail. It is found that the worst cell in 16k SRAM is very unstable and the stability characteristics of the worst cell correspond to approximately 6σ from those of the median cell. It is also found that extraordinarily unstable cells are much more sensitive to VTH change than median cells and that the static noise margin (SNM) and Vmin well correlate only in extraordinarily unstable cells. A simple VTH model for evaluating Vmin is developed and validated by Vmin measured in extraordinarily unstable cells.

  3. Flare Plasma Iron Abundance

    NASA Technical Reports Server (NTRS)

    Dennis, Brian R.; Dan, Chau; Jain, Rajmal; Schwartz, Richard A.; Tolbert, Anne K.

    2008-01-01

    The equivalent width of the iron-line complex at 6.7 keV seen in flare X-ray spectra suggests that the iron abundance of the hottest plasma at temperatures >approx.10 MK may sometimes be significantly lower than the nominal coronal abundance of four times the photospheric value that is commonly assumed. This conclusion is based on X-ray spectral observations of several flares seen in common with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Solar X-ray Spectrometer (SOXS) on the second Indian geostationary satellite, GSAT-2. The implications of this will be discussed as it relates to the origin of the hot flare plasma - either plasma already in the corona that is directly heated during the flare energy release process or chromospheric plasma that is heated by flare-accelerated particles and driven up into the corona. Other possible explanations of lower-than-expected equivalent widths of the iron-line complex will also be discussed.

  4. Detail, Scandia Hotel, view to southwest showing details of balloon ...

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

    Detail, Scandia Hotel, view to southwest showing details of balloon framing, including full two-story studs notched to carry girts supporting second story floor joists (210mm lens) - Scandia Hotel, 225 First Street, Eureka, Humboldt County, CA

  5. 56. DETAIL OF SOUTH SIDE OF WINDING SHEAVES: Detail of ...

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

    56. DETAIL OF SOUTH SIDE OF WINDING SHEAVES: Detail of south side of the winding sheaves. These sheaves drive the California Street cable. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  6. Detail view of ornamental lighting detail of southwest corner of ...

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

    Detail view of ornamental lighting detail of southwest corner of Sixth Street Bridge. Looking northeast - Sixth Street Bridge, Spanning 101 Freeway at Sixth Street, Los Angeles, Los Angeles County, CA

  7. Detail of pumps in troughs, detail of truss attachment ...

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

    Detail of pumps in troughs, detail of truss - attachment to the wall - as well as the troughs themselves. Interior of the main hatchery building, view to the east. - Prairie Creek Fish Hatchery, Hwy. 101, Orick, Humboldt County, CA

  8. 22. PIER NO. IV DETAIL, WITH DETAIL OF SOUTHWEST PORTAL ...

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

    22. PIER NO. IV DETAIL, WITH DETAIL OF SOUTHWEST PORTAL AND SOUTHEAST WEB OF THROUGH TRUSS; VIEW TO NORTH - Nebraska City Bridge, Spanning Missouri River near Highway 2 between Nebraska & Iowa, Nebraska City, Otoe County, NE

  9. An investigation of techniques for the measurement and interpretation of cosmic ray isotopic abundances. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, M. E.

    1977-01-01

    An instrument, the Caltech High Energy Isotope Spectrometer Telescope was developed to measure isotopic abundances of cosmic ray nuclei by employing an energy loss - residual energy technique. A detailed analysis was made of the mass resolution capabilities of this instrument. A formalism, based on the leaky box model of cosmic ray propagation, was developed for obtaining isotopic abundance ratios at the cosmic ray sources from abundances measured in local interstellar space for elements having three or more stable isotopes, one of which is believed to be absent at the cosmic ray sources. It was shown that the dominant sources of uncertainty in the derived source ratios are uncorrelated errors in the fragmentation cross sections and statistical uncertainties in measuring local interstellar abundances. These results were applied to estimate the extent to which uncertainties must be reduced in order to distinguish between cosmic ray production in a solar-like environment and in various environments with greater neutron enrichments.

  10. Influences on physicians' adoption of electronic detailing (e-detailing).

    PubMed

    Alkhateeb, Fadi M; Doucette, William R

    2009-01-01

    E-detailing means using digital technology: internet, video conferencing and interactive voice response. There are two types of e-detailing: interactive (virtual) and video. Currently, little is known about what factors influence physicians' adoption of e-detailing. The objectives of this study were to test a model of physicians' adoption of e-detailing and to describe physicians using e-detailing. A mail survey was sent to a random sample of 2000 physicians practicing in Iowa. Binomial logistic regression was used to test the model of influences on physician adoption of e-detailing. On the basis of Rogers' model of adoption, the independent variables included relative advantage, compatibility, complexity, peer influence, attitudes, years in practice, presence of restrictive access to traditional detailing, type of specialty, academic affiliation, type of practice setting and control variables. A total of 671 responses were received giving a response rate of 34.7%. A total of 141 physicians (21.0%) reported using of e-detailing. The overall adoption model for using either type of e-detailing was found to be significant. Relative advantage, peer influence, attitudes, type of specialty, presence of restrictive access and years of practice had significant influences on physician adoption of e-detailing. The model of adoption of innovation is useful to explain physicians' adoption of e-detailing. PMID:19306198

  11. Oxygen abundance and convection

    NASA Astrophysics Data System (ADS)

    Van't Veer, C.; Cayrel, R.

    The triplet IR lines of O I near 777 nm are computed with the Kurucz's code, modified to accept several convection models. The program has been run with the MLT algorithm, with l/H = 1.25 and 0.5, and with the Canuto-Mazzitelli and Canuto-Goldman-Mazzitelli approaches, on a metal-poor turnoff-star model atmosphere with Teff=6200 K, log g = 4.3, [Fe/H]= -1.5. The results show that the differences in equivalent widths for the 4 cases do not exceed 2 per cent (0.3 mA). The convection treatment is therefore not an issue for the oxygen abundance derived from the permitted lines.

  12. Efficient implementation of the analytic second derivatives of Hartree-Fock and hybrid DFT energies: a detailed analysis of different approximations

    NASA Astrophysics Data System (ADS)

    Bykov, Dmytro; Petrenko, Taras; Izsák, Róbert; Kossmann, Simone; Becker, Ute; Valeev, Edward; Neese, Frank

    2015-07-01

    In this paper, various implementations of the analytic Hartree-Fock and hybrid density functional energy second derivatives are studied. An approximation-free four-centre implementation is presented, and its accuracy is rigorously analysed in terms of self-consistent field (SCF), coupled-perturbed SCF (CP-SCF) convergence and prescreening criteria. The CP-SCF residual norm convergence threshold turns out to be the most important of these. Final choices of convergence thresholds are made such that an accuracy of the vibrational frequencies of better than 5 cm-1 compared to the numerical noise-free results is obtained, even for the highly sensitive low frequencies (<100-200 cm-1). The effects of the choice of numerical grid for density functional exchange-correlation integrations are studied and various weight derivative schemes are analysed in detail. In the second step of the work, approximations are introduced in order to speed up the computation without compromising its accuracy. To this end, the accuracy and efficiency of the resolution of identity approximation for the Coulomb terms and the semi-numerical chain of spheres approximation to the exchange terms are carefully analysed. It is shown that the largest performance improvements are realised if either Hartree-Fock exchange is absent (pure density functionals) and otherwise, if the exchange terms in the CP-SCF step of the calculation are approximated by the COSX method in conjunction with a small integration grid. Default values for all the involved truncation parameters are suggested. For vancomycine (176 atoms and 3593 basis functions), the RIJCOSX Hessian calculation with the B3LYP functional and the def2-TZVP basis set takes ∼3 days using 16 Intel® Xeon® 2.60GHz processors with the COSX algorithm having a net parallelisation scaling of 11.9 which is at least ∼20 times faster than the calculation without the RIJCOSX approximation.

  13. Quantifying the contribution of long-range Saharan dust transport on particulate matter concentrations in Houston, Texas, using detailed elemental analysis.

    PubMed

    Bozlaker, Ayse; Prospero, Joseph M; Fraser, Matthew P; Chellam, Shankararaman

    2013-09-17

    The trans-Atlantic transport of North African dust by summertime trade winds occasionally increases ambient particulate matter (PM) concentrations in Texas above air quality standards. Exemptions from such exceedences can be sought for episodic events that are beyond regulatory control by providing qualitative supportive information such as satellite images and back-trajectories. Herein we demonstrate that chemical mass balancing can successfully isolate, differentiate, and quantify the relative contributions from local and global mineral dust sources through detailed measurements of a wide suite of elements in ambient PM. We identified a major dust storm originating in Northwest Africa in mid-July 2008 which eventually impacted air quality in Houston during July 25, 26, and 27, 2008. Daily PM2.5 and PM10 samples were collected at two sites in Houston over a 2-week period encompassing the Saharan dust episode to quantify the transported mineral dust concentrations during this peak event. Average PM concentrations more than doubled during the Saharan intrusion compared with non-Saharan. Relative concentrations of several elements often associated with anthropogenic sources were significantly diluted by crustal minerals coincident with the large-scale Saharan dust intrusion. During non-Saharan days, local mineral dust sources including cement manufacturing and soil and road dust contributed in total 26% to PM2.5 mass and 50% to PM10 mass; during the three-day Saharan episode the total dust contribution increased to 64% for PM2.5 and 85% for PM10. Importantly, this approach was also able to determine that local emissions of crustal minerals dominated the period immediately following the Saharan dust episode: simple quantification of bulk crustal materials may have misappropriated this elevated PM to trans-Atlantic transport of Saharan dust. PMID:23957269

  14. Detailed magnetic and structural analysis mapping a robust magnetic C4 dome in Sr1 -xNaxFe2As2

    NASA Astrophysics Data System (ADS)

    Taddei, K. M.; Allred, J. M.; Bugaris, D. E.; Lapidus, S.; Krogstad, M. J.; Stadel, R.; Claus, H.; Chung, D. Y.; Kanatzidis, M. G.; Rosenkranz, S.; Osborn, R.; Chmaissem, O.

    2016-04-01

    The recently discovered C4 tetragonal magnetic phase in hole-doped members of the iron-based superconductors provides insights into the origin of unconventional superconductivity. Previously observed in Ba1-xNaxFe2As2 (with A = K, Na), the C4 magnetic phase exists within the well-studied C2 spin-density-wave dome, arising just before the complete suppression of antiferromagnetic order but after the onset of superconductivity. Here, we present detailed x-ray and neutron diffraction studies of Sr1-xNaxFe2As2 (0.10 ≤x ≤0.60 ) to determine their structural evolution and the extent of the C4 phase. Spanning Δ x ˜0.14 in composition, the C4 phase is found to extend over a larger range of compositions, and to exhibit a significantly higher transition temperature, Tr˜65 K, than in either of the other systems in which it has been observed. The onset of this phase is seen near a composition (x ˜0.30 ) where the bonding angles of the Fe2As2 layers approach the perfect 109 .46∘ tetrahedral angle. We discuss the possible role of this return to a higher symmetry environment for the magnetic iron site in triggering the magnetic reorientation and the coupled reentrance to the tetragonal structure. Finally, we present a phase diagram, complete with the C4 phase, and use its observation in a third hole-doped 122 system to suggest the universality of this phase.

  15. Detailed functional characterization of glycosylated and nonglycosylated variants of malaria vaccine candidate PfAMA1 produced in Nicotiana benthamiana and analysis of growth inhibitory responses in rabbits.

    PubMed

    Boes, Alexander; Spiegel, Holger; Edgue, Gueven; Kapelski, Stephanie; Scheuermayer, Matthias; Fendel, Rolf; Remarque, Edmond; Altmann, Friedrich; Maresch, Daniel; Reimann, Andreas; Pradel, Gabriele; Schillberg, Stefan; Fischer, Rainer

    2015-02-01

    One of the most promising malaria vaccine candidate antigens is the Plasmodium falciparum apical membrane antigen 1 (PfAMA1). Several studies have shown that this blood-stage antigen can induce strong parasite growth inhibitory antibody responses. PfAMA1 contains up to six recognition sites for N-linked glycosylation, a post-translational modification that is absent in P. falciparum. To prevent any potential negative impact of N-glycosylation, the recognition sites have been knocked out in most PfAMA1 variants expressed in eukaryotic hosts. However, N-linked glycosylation may increase efficacy by improving immunogenicity and/or focusing the response towards relevant epitopes by glycan masking. We describe the production of glycosylated and nonglycosylated PfAMA1 in Nicotiana benthamiana and its detailed characterization in terms of yield, integrity and protective efficacy. Both PfAMA1 variants accumulated to high levels (>510 μg/g fresh leaf weight) after transient expression, and high-mannose-type N-glycans were confirmed for the glycosylated variant. No significant differences between the N. benthamiana and Pichia pastoris PfAMA1 variants were detected in conformation-sensitive ligand-binding studies. Specific titres of >2 × 10(6) were induced in rabbits, and strong reactivity with P. falciparum schizonts was observed in immunofluorescence assays, as well as up to 100% parasite growth inhibition for both variants, with IC₅₀ values of ~35 μg/mL. Competition assays indicated that a number of epitopes were shielded from immune recognition by N-glycans, warranting further studies to determine how glycosylation can be used for the directed targeting of immune responses. These results highlight the potential of plant transient expression systems as a production platform for vaccine candidates. PMID:25236489

  16. Magnetocrystalline anisotropy energy of Fe (001) and Fe (110) slabs and nanoclusters: A detailed local analysis within a tight-binding model

    NASA Astrophysics Data System (ADS)

    Li, Dongzhe; Smogunov, Alexander; Barreteau, Cyrille; Ducastelle, François; Spanjaard, Daniel

    2013-12-01

    We report tight-binding (TB) calculations of magnetocrystalline anisotropy energy (MAE) of iron slabs and nanoclusters with a particular focus on local analysis. After clarifying various concepts and formulations for the determination of MAE, we apply our realistic TB model to the analysis of the magnetic anisotropy of Fe (001), Fe (110) slabs and of two large Fe clusters with (001) and (110) facets only: a truncated pyramid and a truncated bipyramid containing 620 and 1096 atoms, respectively. It is shown that the MAE of slabs originates mainly from outer layers; a small contribution from the subsurface gives rise, however, to an oscillatory behavior for large thicknesses. Interestingly, the MAE of the nanoclusters considered is almost solely due to (001) facets and the base perimeter of the pyramid. We believe that this fact could be used to efficiently control the anisotropy of iron nanoparticles and could also have consequences on their spin dynamics.

  17. M31 GLOBULAR CLUSTER ABUNDANCES FROM HIGH-RESOLUTION, INTEGRATED-LIGHT SPECTROSCOPY

    SciTech Connect

    Colucci, Janet E.; McWilliam, Andrew; Cohen, Judith G. E-mail: sacamero@umich.ed E-mail: andy@ociw.ed

    2009-10-10

    We report the first detailed chemical abundances for five globular clusters (GCs) in M31 from high-resolution (R approx 25,000) spectroscopy of their integrated light (IL). These GCs are the first in a larger set of clusters observed as part of an ongoing project to study the formation history of M31 and its GC population. The data presented here were obtained with the HIRES echelle spectrograph on the Keck I telescope and are analyzed using a new IL spectra analysis method that we have developed. In these clusters, we measure abundances for Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Y, and Ba, ages >=10 Gyr, and a range in [Fe/H] of -0.9 to -2.2. As is typical of Milky Way GCs, we find these M31 GCs to be enhanced in the alpha-elements Ca, Si, and Ti relative to Fe. We also find [Mg/Fe] to be low relative to other [alpha/Fe], and [Al/Fe] to be enhanced in the IL abundances. These results imply that abundances of Mg, Al (and likely O, Na) recovered from IL do display the inter- and intra-cluster abundance variations seen in individual Milky Way GC stars, and that special care should be taken in the future in interpreting low- or high-resolution IL abundances of GCs that are based on Mg-dominated absorption features. Fe-peak and the neutron-capture elements Ba and Y also follow Milky Way abundance trends. We also present high-precision velocity dispersion measurements for all five M31 GCs, as well as independent constraints on the reddening toward the clusters from our analysis.

  18. Detailed analysis of Helicobacter pylori Fur-regulated promoters reveals a Fur box core sequence and novel Fur-regulated genes.

    PubMed

    Pich, Oscar Q; Carpenter, Beth M; Gilbreath, Jeremy J; Merrell, D Scott

    2012-06-01

    In Helicobacter pylori, iron balance is controlled by the Ferric uptake regulator (Fur), an iron-sensing repressor protein that typically regulates expression of genes implicated in iron transport and storage. Herein, we carried out extensive analysis of Fur-regulated promoters and identified a 7-1-7 motif with dyad symmetry (5'-TAATAATnATTATTA-3'), which functions as the Fur box core sequence of H. pylori. Addition of this sequence to the promoter region of a typically non-Fur regulated gene was sufficient to impose Fur-dependent regulation in vivo. Moreover, mutation of this sequence within Fur-controlled promoters negated regulation. Analysis of the H. pylori chromosome for the occurrence of the Fur box established the existence of well-conserved Fur boxes in the promoters of numerous known Fur-regulated genes, and revealed novel putative Fur targets. Transcriptional analysis of the new candidate genes demonstrated Fur-dependent repression of HPG27_51, HPG27_52, HPG27_199, HPG27_445, HPG27_825 and HPG27_1063, as well as Fur-mediated activation of the cytotoxin associated gene A, cagA (HPG27_507). Furthermore, electrophoretic mobility shift assays confirmed specific binding of Fur to the promoters of each of these genes. Future experiments will determine whether loss of Fur regulation of any of these particular genes contributes to the defects in colonization exhibited by the H. pylori fur mutant. PMID:22507395

  19. Nanomanipulation-Coupled Matrix-Assisted Laser Desorption/ Ionization-Direct Organelle Mass Spectrometry: A Technique for the Detailed Analysis of Single Organelles

    NASA Astrophysics Data System (ADS)

    Phelps, Mandy S.; Sturtevant, Drew; Chapman, Kent D.; Verbeck, Guido F.

    2016-02-01

    We describe a novel technique combining precise organelle microextraction with deposition and matrix-assisted laser desorption/ionization (MALDI) for a rapid, minimally invasive mass spectrometry (MS) analysis of single organelles from living cells. A dual-positioner nanomanipulator workstation was utilized for both extraction of organelle content and precise co-deposition of analyte and matrix solution for MALDI-direct organelle mass spectrometry (DOMS) analysis. Here, the triacylglycerol (TAG) profiles of single lipid droplets from 3T3-L1 adipocytes were acquired and results validated with nanoelectrospray ionization (NSI) MS. The results demonstrate the utility of the MALDI-DOMS technique as it enabled longer mass analysis time, higher ionization efficiency, MS imaging of the co-deposited spot, and subsequent MS/MS capabilities of localized lipid content in comparison to NSI-DOMS. This method provides selective organellar resolution, which complements current biochemical analyses and prompts for subsequent subcellular studies to be performed where limited samples and analyte volume are of concern.

  20. Actinide abundances in ordinary chondrites

    NASA Technical Reports Server (NTRS)

    Hagee, B.; Bernatowicz, T. J.; Podosek, F. A.; Johnson, M. L.; Burnett, D. S.

    1990-01-01

    Measurements of actinide and light REE (LREE) abundances and of phosphate abundances in equilibrated ordinary chondrites were obtained and were used to define the Pu abundance in the solar system and to determine the degree of variation of actinide and LREE abundances. The results were also used to compare directly the Pu/U ratio with the earlier obtained ratio determined indirectly, as (Pu/Nd)x(Nd/U), assuming that Pu behaves chemically as a LREE. The data, combined with high-accuracy isotope-dilution data from the literature, show that the degree of gram-scale variability of the Th, U, and LREE abundances for equilibrated ordinary chondrites is a factor of 2-3 for absolute abundances and up to 50 percent for relative abundances. The observed variations are interpreted as reflecting the differences in the compositions and/or proportions of solar nebula components accreted to ordinary chondrite parent bodies.

  1. U, Th, Pb and REE abundances and Pb 207/Pb 206 ages of individual minerals in returned lunar material by ion microprobe mass analysis.

    NASA Technical Reports Server (NTRS)

    Andersen, C. A.; Hinthorne, J. R.

    1972-01-01

    Results of ion microprobe analyses of Apollo 11, 12 and 14 material, showing that U, Th, Pb and REE are concentrated in accessory minerals such as apatite, whitlockite, zircon, baddeleyite, zirkelite, and tranquillityite. Th/U ratios are found to vary by over a factor of 40 in these minerals. K, Ba, Rb and Sr have been localized in a K rich, U and Th poor glass phase that is commonly associated with the U and Th bearing accessory minerals. Li is observed to be fairly evenly distributed between the various accessory phases. The phosphates have been found to have REE abundance patterns (normalized to the chondrite abundances) that are fairly flat, while the Zr bearing minerals have patterns that rise steeply, by factors of ten or more, from La to Gd. All the accessory minerals have large negative Eu anomalies. Radiometric age dates (Pb 207/Pb 206) of the individual U and Th bearing minerals compare favorably with the Pb 207/Pb 206 age of the bulk rocks.

  2. A detailed analysis of the energy levels configuration existing in the band gap of supersaturated silicon with titanium for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Pérez, E.; Dueñas, S.; Castán, H.; García, H.; Bailón, L.; Montero, D.; García-Hernansanz, R.; García-Hemme, E.; Olea, J.; González-Díaz, G.

    2015-12-01

    The energy levels created in supersaturated n-type silicon substrates with titanium implantation in the attempt to create an intermediate band in their band-gap are studied in detail. Two titanium ion implantation doses (1013 cm-2 and 1014 cm-2) are studied in this work by conductance transient technique and admittance spectroscopy. Conductance transients have been measured