1,141 research outputs found

    Dynamic Compaction Using Select Fill Displacement Methods

    Get PDF
    Since its development as a full-fledged soil compaction technique by Louis Menard in the late 1960s, the Dynamic Compaction method has evolved considerably and has become an increasingly efficient ground improvement system. Among the special techniques borne out of this evolution is the use of Dynamic Compaction to create large-diameter columns using select granular material. This method serves to not only provide increased support and better distribution of imposed loads through the columns themselves, but also augments the capability of the process in improving the host soils to a depth and degree not possible using conventional DC methods. Three case histories are presented to illustrate this technique and its benefits in terms of increased effectiveness and range of application

    Extinction Maps Toward The Milky Way Bulge: Two-Dimensional And Three-Dimensional Tests With APOGEE

    Get PDF
    Galactic interstellar extinction maps are powerful and necessary tools for Milky Way structure and stellar population analyses, particularly toward the heavily reddened bulge and in the midplane. However, due to the difficulty of obtaining reliable extinction measures and distances for a large number of stars that are independent of these maps, tests of their accuracy and systematics have been limited. Our goal is to assess a variety of photometric stellar extinction estimates, including both two-dimensional and three-dimensional extinction maps, using independent extinction measures based on a large spectroscopic sample of stars toward the Milky Way bulge. We employ stellar atmospheric parameters derived from high-resolution H-band Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra, combined with theoretical stellar isochrones, to calculate line-of-sight extinction and distances for a sample of more than 2400 giants toward the Milky Way bulge. We compare these extinction values to those predicted by individual near-IR and near+mid-IR stellar colors, two-dimensional bulge extinction maps, and three-dimensional extinction maps. The long baseline, near+mid-IR stellar colors are, on average, the most accurate predictors of the APOGEE extinction estimates, and the two-dimensional and three-dimensional extinction maps derived from different stellar populations along different sightlines show varying degrees of reliability. We present the results of all of the comparisons and discuss reasons for the observed discrepancies. We also demonstrate how the particular stellar atmospheric models adopted can have a strong impact on this type of analysis, and discuss related caveats.NSF Astronomy & Astrophysics Postdoctoral Fellowship AST-1203017Physics Frontier Center/Joint Institute for Nuclear Astrophysics (JINA) PHY 08-22648U.S. National Science FoundationAlfred P. Sloan FoundationParticipating InstitutionsU.S. Department of Energy Office of Science ANR-12-BS05-0015-01Astronom

    Just in time and future-proofing? Policy, challenges and opportunities in the professional development of part-time teachers

    Get PDF
    Part-time teachers form a growing proportion of the global HE workforce. Their backgrounds can vary from Graduate Teaching Assistants (GTAs) teaching for the first time, to practitioners bringing workplace experience into HE and sessional teachers, all with differing professional development needs. This paper builds on previous research to consider structures and practices promoting sustainable, effective professional development for part-timers, to propose proactive holistic professional development, and raise institutional awareness of the challenges of reaching part-timers. A case study, exploring the lived experiences of part-time staff, illustrates key features of part-timers’ preparation for their current work and future aspirations

    The First Ultra-cool Brown Dwarf Discovered by the Wide-field Infrared Survey Explorer

    Get PDF
    We report the discovery of the first new ultra-cool brown dwarf (BDs) found with the Wide-field Infrared Survey Explorer (WISE). The object’s preliminary designation is WISEPC J045853.90+643451.9. Follow-up spectroscopy with the LUCIFER instrument on the Large Binocular Telescope indicates that it is a very late-type T dwarf with a spectral type approximately equal to T9. Fits to an IRTF/SpeX 0.8–2.5 μm spectrum to the model atmospheres of Marley and Saumon indicate an effective temperature of approximately 600 K as well as the presence of vertical mixing in its atmosphere. The new BD is easily detected by WISE, with a signal-to-noise ratio of ~36 at 4.6 μm. Current estimates place it at a distance of 6–10 pc. This object represents the first in what will likely be hundreds of nearby BDs found by WISE that will be suitable for follow-up observations, including those with the James Webb Space Telescope. One of the two primary scientific goals of the WISE mission is to find the coolest, closest stars to our Sun; the discovery of this new BD proves that WISE is capable of fulfilling this objective

    THE ELEVENTH AND TWELFTH DATA RELEASES OF THE SLOAN DIGITAL SKY SURVEY: FINAL DATA FROM SDSS-III

    Get PDF
    Citation: Alam, S., Albareti, F. D., Prieto, C. A., Anders, F., Anderson, S. F., Anderton, T., . . . Zhu, G. T. (2015). THE ELEVENTH AND TWELFTH DATA RELEASES OF THE SLOAN DIGITAL SKY SURVEY: FINAL DATA FROM SDSS-III. Astrophysical Journal Supplement Series, 219(1), 27. doi:10.1088/0067-0049/219/1/12The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg(2) of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg(2) of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg(2); 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra.Additional Authors: Berlind, A. A.;Beutler, F.;Bhardwaj, V.;Bird, J. C.;Bizyaev, D.;Blake, C. H.;Blanton, M. R.;Blomqvist, M.;Bochanski, J. J.;Bolton, A. S.;Bovy, J.;Bradley, A. S.;Brandt, W. N.;Brauer, D. E.;Brinkmann, J.;Brown, P. J.;Brownstein, J. R.;Burden, A.;Burtin, E.;Busca, N. G.;Cai, Z.;Capozzi, D.;Rosell, A. C.;Carr, M. A.;Carrera, R.;Chambers, K. C.;Chaplin, W. J.;Chen, Y. C.;Chiappini, C.;Chojnowski, S. D.;Chuang, C. H.;Clerc, N.;Comparat, J.;Covey, K.;Croft, R. A. C.;Cuesta, A. J.;Cunha, K.;da Costa, L. N.;Da Rio, N.;Davenport, J. R. A.;Dawson, K. S.;De Lee, N.;Delubac, T.;Deshpande, R.;Dhital, S.;Dutra-Ferreira, L.;Dwelly, T.;Ealet, A.;Ebelke, G. L.;Edmondson, E. M.;Eisenstein, D. J.;Ellsworth, T.;Elsworth, Y.;Epstein, C. R.;Eracleous, M.;Escoffier, S.;Esposito, M.;Evans, M. L.;Fan, X. H.;Fernandez-Alvar, E.;Feuillet, D.;Ak, N. F.;Finley, H.;Finoguenov, A.;Flaherty, K.;Fleming, S. W.;Font-Ribera, A.;Foster, J.;Frinchaboy, P. M.;Galbraith-Frew, J. G.;Garcia, R. A.;Garcia-Hernandez, D. A.;Perez, A. E. G.;Gaulme, P.;Ge, J.;Genova-Santos, R.;Georgakakis, A.;Ghezzi, L.;Gillespie, B. A.;Girardi, L.;Goddard, D.;Gontcho, S. G. A.;Hernandez, J. I. G.;Grebel, E. K.;Green, P. J.;Grieb, J. N.;Grieves, N.;Gunn, J. E.;Guo, H.;Harding, P.;Hasselquist, S.;Hawley, S. L.;Hayden, M.;Hearty, F. R.;Hekker, S.;Ho, S.;Hogg, D. W.;Holley-Bockelmann, K.;Holtzman, J. A.;Honscheid, K.;Huber, D.;Huehnerhoff, J.;Ivans, II;Jiang, L. H.;Johnson, J. A.;Kinemuchi, K.;Kirkby, D.;Kitaura, F.;Klaene, M. A.;Knapp, G. R.;Kneib, J. P.;Koenig, X. P.;Lam, C. R.;Lan, T. W.;Lang, D. T.;Laurent, P.;Le Goff, J. M.;Leauthaud, A.;Lee, K. G.;Lee, Y. S.;Licquia, T. C.;Liu, J.;Long, D. C.;Lopez-Corredoira, M.;Lorenzo-Oliveira, D.;Lucatello, S.;Lundgren, B.;Lupton, R. H.;Mack, C. E.;Mahadevan, S.;Maia, M. A. G.;Majewski, S. R.;Malanushenko, E.;Malanushenko, V.;Manchado, A.;Manera, M.;Mao, Q. Q.;Maraston, C.;Marchwinski, R. C.;Margala, D.;Martell, S. L.;Martig, M.;Masters, K. L.;Mathur, S.;McBride, C. K.;McGehee, P. M.;McGreer, I. D.;McMahon, R. G.;Menard, B.;Menzel, M. L.;Merloni, A.;Meszaros, S.;Miller, A. A.;Miralda-Escude, J.;Miyatake, H.;Montero-Dorta, A. D.;More, S.;Morganson, E.;Morice-Atkinson, X.;Morrison, H. L.;Mosser, B.;Muna, D.;Myers, A. D.;Nandra, K.;Newman, J. A.;Neyrinck, M.;Nguyen, D. C.;Nichol, R. C.;Nidever, D. L.;Noterdaeme, P.;Nuza, S. E.;O'Connell, J. E.;O'Connell, R. W.;O'Connell, R.;Ogando, R. L. C.;Olmstead, M. D.;Oravetz, A. E.;Oravetz, D. J.;Osumi, K.;Owen, R.;Padgett, D. L.;Padmanabhan, N.;Paegert, M.;Palanque-Delabrouille, N.;Pan, K. K.;Parejko, J. K.;Paris, I.;Park, C.;Pattarakijwanich, P.;Pellejero-Ibanez, M.;Pepper, J.;Percival, W. J.;Perez-Fournon, I.;Perez-Rafols, I.;Petitjean, P.;Pieri, M. M.;Pinsonneault, M. H.;de Mello, G. F. P.;Prada, F.;Prakash, A.;Price-Whelan, A. M.;Protopapas, P.;Raddick, M. J.;Rahman, M.;Reid, B. A.;Rich, J.;Rix, H. W.;Robin, A. C.;Rockosi, C. M.;Rodrigues, T. S.;Rodriguez-Torres, S.;Roe, N. A.;Ross, A. J.;Ross, N. P.;Rossi, G.;Ruan, J. J.;Rubino-Martin, J. A.;Rykoff, E. S.;Salazar-Albornoz, S.;Salvato, M.;Samushia, L.;Sanchez, A. G.;Santiago, B.;Sayres, C.;Schiavon, R. P.;Schlegel, D. J.;Schmidt, S. J.;Schneider, D. P.;Schultheis, M.;Schwope, A. D.;Scoccola, C. G.;Scott, C.;Sellgren, K.;Seo, H. J.;Serenelli, A.;Shane, N.;Shen, Y.;Shetrone, M.;Shu, Y. P.;Aguirre, V. S.;Sivarani, T.;Skrutskie, M. F.;Slosar, A.;Smith, V. V.;Sobreira, F.;Souto, D.;Stassun, K. G.;Steinmetz, M.;Stello, D.;Strauss, M. A.;Streblyanska, A.;Suzuki, N.;Swanson, M. E. C.;Tan, J. C.;Tayar, J.;Terrien, R. C.;Thakar, A. R.;Thomas, D.;Thomas, N.;Thompson, B. A.;Tinker, J. L.;Tojeiro, R.;Troup, N. W.;Vargas-Magana, M.;Vazquez, J. A.;Verde, L.;Viel, M.;Vogt, N. P.;Wake, D. A.;Wang, J.;Weaver, B. A.;Weinberg, D. H.;Weiner, B. J.;White, M.;Wilson, J. C.;Wisniewski, J. P.;Wood-Vasey, W. M.;Yeche, C.;York, D. G.;Zakamska, N. L.;Zamora, O.;Zasowski, G.;Zehavi, I.;Zhao, G. B.;Zheng, Z.;Zhou, X.;Zhou, Z. M.;Zou, H.;Zhu, G. T

    Linguistic validation, validity and reliability of the British English versions of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and QuickDASH in people with rheumatoid arthritis

    Get PDF
    Background: Although the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire is widely used in the UK, no British English version is available. The aim of this study was to linguistically validate the DASH into British English and then test the reliability and validity of the British English DASH, (including the Work and Sport/Music DASH) and QuickDASH, in people with rheumatoid arthritis (RA). Methods: The DASH was forward translated, reviewed by an expert panel and cognitive debriefing interviews undertaken with 31 people with RA. Content validity was evaluated using the ICF Core Set for RA. Participants with RA (n=340) then completed the DASH, Health Assessment Questionnaire (HAQ), Short Form Health Survey v2 (SF36v2) and Measure of Activity Performance of the Hand (MAPHAND). We examined internal consistency and concurrent validity for the DASH, Work and Sport/Music DASH modules and QuickDASH. Participants repeated the DASH to assess test-retest reliability. Results: Minor wording changes were made as required. The DASH addresses a quarter of Body Function and half of Activities and Participation codes in the ICF RA Core Set. Internal consistency for DASH scales were consistent with individual use (Cronbach’s alpha = 0.94-0.98). Concurrent validity was strong with the HAQ (rs = 0.69-0.91), SF36v2 Physical Function (rs = -0.71 - -0.85), Bodily Pain (rs = -0.71 - -0.74) scales and MAPHAND (rs =0.71-0.93). Test-retest reliability was good (rs = 0.74-0.95). Conclusions: British English versions of the DASH, QuickDASH and Work and Sport/Music modules are now available to evaluate upper limb disabilities in the UK. The DASH, QuickDASH, Work and Sport/Music modules are reliable and valid to use in clinical practice and research with British people with RA

    Target Selection for the SDSS-IV APOGEE-2 Survey

    Full text link
    APOGEE-2 is a high-resolution, near-infrared spectroscopic survey observing roughly 300,000 stars across the entire sky. It is the successor to APOGEE and is part of the Sloan Digital Sky Survey IV (SDSS-IV). APOGEE-2 is expanding upon APOGEE's goals of addressing critical questions of stellar astrophysics, stellar populations, and Galactic chemodynamical evolution using (1) an enhanced set of target types and (2) a second spectrograph at Las Campanas Observatory in Chile. APOGEE-2 is targeting red giant branch (RGB) and red clump (RC) stars, RR Lyrae, low-mass dwarf stars, young stellar objects, and numerous other Milky Way and Local Group sources across the entire sky from both hemispheres. In this paper, we describe the APOGEE-2 observational design, target selection catalogs and algorithms, and the targeting-related documentation included in the SDSS data releases.Comment: 19 pages, 6 figures. Accepted to A

    The Shoulder Pain and Disability Index demonstrates factor, construct and longitudinal validity

    Get PDF
    BACKGROUND: The Shoulder Pain and Disability Index (SPADI) is a self-report measure developed to evaluate patients with shoulder pathology. While some validation has been conducted, broader analyses are indicated. This study determined aspects of cross-sectional and longitudinal validity of the SPADI. METHODS: Community volunteers (n = 129) who self-identified as having shoulder pain were enrolled. Patients were examined by a physical therapist using a standardized assessment process to insure that their pain was musculoskeletal in nature. This included examination of pain reported during active and passive shoulder motion as reported on a visual analogue pain scale. Patients completed the SPADI, the Coping Strategies Questionnaire (CSQ) and the Sickness Impact Profile (SIP) at a baseline assessment and again 3 and 6 months later. Factor analysis with varimax rotation was used to assess subscale structure. Expectations regarding convergent and divergent subscales of CSQ and SIP were determined a priori and analysed using Pearson correlations. Constructed hypotheses that patients with a specific diagnosis or on pain medication would demonstrate higher SPADI scores were tested. Correlations between the observed changes recorded across different instruments were used to assess longitudinal validity. RESULTS: The internal consistencies of the SPADI subscales were high (α > 0.92). Factor analysis with varimax rotation indicated that the majority of items fell into 2 factors that represent pain and disability. Two difficult functional items tended to align with pain items. Higher pain and disability was correlated to passive or negative coping strategies, i.e., praying/hoping, catastrophizing on the CSQ. The correlations between subscales of the SPADI and SIP were low with divergent subscales and low to moderate with convergent subscales. Correlations, r > 0.60, were observed between the SPADI and pain reported on a VAS pain scale during active and passive movement. The two constructed validity hypotheses (on diagnosis and use of pain medications) were both supported (p < 0.01). The SPADI demonstrated significant changes over time, but these were poorly correlated to the SIP or CSQ suggesting that these scales measure different parameters. CONCLUSION: The SPADI is a valid measure to assess pain and disability in community-based patients reporting shoulder pain due to musculoskeletal pathology

    The SPLASH Survey: Kinematics of Andromeda's Inner Spheroid

    Full text link
    The combination of large size, high stellar density, high metallicity, and Sersic surface brightness profile of the spheroidal component of the Andromeda galaxy (M31) within R_proj ~ 20 kpc suggest that it is unlike any subcomponent of the Milky Way. In this work we capitalize on our proximity to and external view of M31 to probe the kinematical properties of this "inner spheroid." We employ a Markov chain Monte Carlo (MCMC) analysis of resolved stellar kinematics from Keck/DEIMOS spectra of 5651 red giant branch stars to disentangle M31's inner spheroid from its stellar disk. We measure the mean velocity and dispersion of the spheroid in each of five spatial bins after accounting for a locally cold stellar disk as well as the Giant Southern Stream and associated tidal debris. For the first time, we detect significant spheroid rotation (v_rot ~ 50 km/s) beyond R_proj ~ 5 kpc. The velocity dispersion decreases from about 140 km/s at R_proj = 7 kpc to 120 km/s at R_proj = 14 kpc, consistent to 2 sigma with existing measurements and models. We calculate the probability that a given star is a member of the spheroid and find that the spheroid has a significant presence throughout the spatial extent of our sample. Lastly, we show that the flattening of the spheroid is due to velocity anisotropy in addition to rotation. Though this suggests that the inner spheroid of M31 more closely resembles an elliptical galaxy than a typical spiral galaxy bulge, it should be cautioned that our measurements are much farther out (2 - 14 r_eff) than for the comparison samples.Comment: Accepted for publication in Ap

    Target Selection for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)

    Get PDF
    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a high-resolution infrared spectroscopic survey spanning all Galactic environments (i.e., bulge, disk, and halo), with the principal goal of constraining dynamical and chemical evolution models of the Milky Way. APOGEE takes advantage of the reduced effects of extinction at infrared wavelengths to observe the inner Galaxy and bulge at an unprecedented level of detail. The survey's broad spatial and wavelength coverage enables users of APOGEE data to address numerous Galactic structure and stellar populations issues. In this paper we describe the APOGEE targeting scheme and document its various target classes to provide the necessary background and reference information to analyze samples of APOGEE data with awareness of the imposed selection criteria and resulting sample properties. APOGEE's primary sample consists of ~100,000 red giant stars, selected to minimize observational biases in age and metallicity. We present the methodology and considerations that drive the selection of this sample and evaluate the accuracy, efficiency, and caveats of the selection and sampling algorithms. We also describe additional target classes that contribute to the APOGEE sample, including numerous ancillary science programs, and we outline the targeting data that will be included in the public data releases.Comment: Accepted to AJ. 31 pages, 11 figure
    • …
    corecore