29,541 research outputs found

    A systematic review of whole class, subject based, pedagogies with reported outcomes for the academic and social inclusion of pupils with special educational needs in mainstream classrooms

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    Schools across the world have responded to international and national initiatives designed to further the development of inclusive education. In England, there is a statutory requirement for all schools to provide effective learning opportunities for all pupils (QCA, 2000) and children with special educational needs (SEN) are positioned as having a right to be within mainstream classrooms accessing an appropriate curriculum (SENDA, 2001). Previous reviews which have sought to identify classroom practices that support the inclusion of children with SEN have been technically non-systematic and hence a need for a systematic review within this area has been identified (Nind et al., 2004; Rix et al., 2006). This systematic literature review is the last in a series of three

    Pressure-supported ionized gas in S0 galaxies

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    Rotation curves and velocity dispersion profiles are presented for both the stellar and gaseous components of a sample of S0 galaxies. In all galaxies the central velocity dispersion of the ionized gas exceeds 150 km/s. In some galaxies the gas dispersion remains as high as the stellar one over an extended radial range, showing that random motions are crucial for the dynamical support of the gas. Such a pressure support may explain why the observed gas rotation curves in galaxy bulges often fall short of the circular velocity predicted from the stellar kinematic models. It is suggested that, in addition to the acquisition of external material, some of the observed gas in S0 galaxies may have been shed from bulge stars

    The kinematics and the origin of the ionized gas in NGC 4036

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    We present the kinematics and photometry of the stars and of the ionized gas near the centre of the S0 galaxy NGC 4036. Dynamical models based on the Jeans equation have been constructed from the stellar data to determine the gravitational potential in which the ionized gas is expected to orbit. Inside 10 arcsec, the observed gas rotation curve falls well short of the predicted circular velocity. Over a comparable radial region the observed gas velocity dispersion is far higher than that expected from thermal motions or small-scale turbulence, corroborating that the gas cannot be following the streamlines of nearly closed orbits. We explore several avenues to understand the dynamical state of the gas. (1) We treat the gas as a collisionless ensemble of cloudlets and apply the Jeans equation to it; this modelling shows that inside 4 arcsec the gas velocity dispersion is just high enough to explain quantitatively the absence of rotation. (2) Alternatively, we explore whether the gas may arise from the `just shed' mass-loss envelopes of the bulge stars, in which case their kinematics should simply mimic that of the stars; the latter approach matches the data better than (1), but still fails to explain the low velocity dispersion and slow rotation velocity of the gas for 5<r<10 arcsec. (3) Finally, we explore whether drag forces on the ionized gas may aid in explaining its peculiar kinematics. While all these approaches provide a much better description of the data than cold gas on closed orbits, we do not yet have a definitive model to describe the observed gas kinematics at all radii. We outline observational tests to understand the enigmatic nature of the ionized gas

    Chemically Peculiar A and F Stars with Enhanced s-process and Iron-peak Elements: Stellar Radiative Acceleration at Work

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    We present ⪆15,000 metal-rich ([Fe/H] > -0.2 dex) A and F stars whose surface abundances deviate strongly from solar abundance ratios and cannot plausibly reflect their birth material composition. These stars are identified by their high [Ba/Fe] abundance ratios ([Ba/Fe] > 1.0 dex) in the LAMOST DR5 spectra analyzed by Xiang et al. They are almost exclusively main-sequence and subgiant stars with T eff ⪆ 6300 K. Their distribution in the Kiel diagram (T eff-log g) traces a sharp border at low temperatures along a roughly fixed-mass trajectory (around 1.4 M o ̇) that corresponds to an upper limit in convective envelope mass fraction of around 10-4. Most of these stars exhibit distinctly enhanced abundances of iron-peak elements (Cr, Mn, Fe, Ni) but depleted abundances of Mg and Ca. Rotational velocity measurements from GALAH DR2 show that the majority of these stars rotate slower than typical stars in an equivalent temperature range. These characteristics suggest that they are related to the so-called Am/Fm stars. Their abundance patterns are qualitatively consistent with the predictions of stellar evolution models that incorporate radiative acceleration, suggesting they are a consequence of stellar internal evolution, particularly involving the competition between gravitational settling and radiative acceleration. These peculiar stars constitute 40% of the whole population of stars with mass above 1.5 M o ̇, affirming that "peculiar"photospheric abundances due to stellar evolution effects are a ubiquitous phenomenon for these intermediate-mass stars. This large sample of Ba-enhanced, chemically peculiar A/F stars with individual element abundances provides the statistics to test more stringently the mechanisms that alter the surface abundances in stars with radiative envelopes

    The Gaia-ASAS-SN classical cepheid sample. I. Sample selection

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    We present a well-defined and characterized all-sky sample of classical Cepheids in the Milky Way, obtained by combining two time-domain all-sky surveys: Gaia DR2 (Gaia Collaboration et al. 2018) and All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014). We first use parallax and variability information from Gaia to select ∼30,000 bright (G &lt; 17) Cepheid candidates with MK &lt; - 1. We then analyze their ASAS-SN V-band light curves, determining periods and classifying the light curves using their Fourier parameters. This results in ∼1900 likely Galactic Cepheids, which we estimate to be ≳90% complete and pure within our adopted selection criteria. This is the largest all-sky sample of Milky Way Cepheids that has such a well-characterized selection function, needed for population modeling and for systematic spectroscopic follow-up foreseen with Sloan Digital Sky Survey-V. About 130 of these potential Cepheids have not been documented in the literature even as possible candidates

    Capt. W. H. Graves

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    Engraving of Captain W. H. Graves who was an attorney, businessman and author in Birmingham, Alabama. He wrote the book titled: Junius Finally Discovered

    Precipitation of supersaturated solute in H ion irradiated Fe-Au and Fe-Au-W alloys studied by positron annihilation spectroscopy

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    The effect of thermal aging of homogenized Fe-Au and Fe-Au-W alloys, irradiated at room temperature with hydrogen ions, was studied for an aging treatment at 300 °C for aging times up to 100 h. The aging behavior of the Fe-based alloys is compared to the results for pure Fe. The precipitation behavior of Au-rich and W-rich precipitates and its correlation to the H+ irradiation-induced defects is investigated by variable energy positron annihilation spectroscopy (VEPAS). The formation of open-volume defects after irradiation is monitored by an increase in the S parameter, while the recovery of the vacancy-like defects and the formation of precipitates are signalled by an increase in the W parameter. Au-rich precipitation continuously develops during long-term aging, as indicated by the increase in the W parameter. The change of the W parameter in the Fe-Au-W alloy is not only due to the effect of solute W on the Au precipitates, but also because of the interface of W-rich Laves phase with matrix.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Novel Aerospace MaterialsRST/Fundamental Aspects of Materials and Energ

    Lydia H. Hart Diary

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    Diary, 1823-1830, 1875 and loose papers 1813, 1831, and undated of Lydia H. Hart of Richmond, Virginia and later Walden, Orange County, New York. The Diary was started by Lydia H. Hart, the wife of Reverend William H. Hart, who was the rector of St. John’s Church in Richmond, VA and later St. Andrews Church in Walden, New York. Diary entries include day-to-day activities and meetings with local neighbors and church patron’s. These neighbors included Elizabeth Van Lew and her parents, which Lydia Hart writes about several times. Most dated entries also include discussion of specific bible verses or Rev. Hart’s sermons. Notable entries include a description of the funeral service for Rev. John Buchanan, former rector of St. John’s Church from 1795 to 1822. Diary entries are chronological and more frequent for 1823 and become less frequent in 1823. In 1828, Lydia Hart moved to New York and eventually to Walden, New York in May 1830.At the end of the diary entries is an entry form another author, possibly by Mary. W. Hart dated 1875. Lydia Hart died in 1831 and could not have made the entry.At the back of the diary and upside down to the diary entries are transcriptions of letters and poems of Lydia Hart’s to various newspapers and and personnel correspondence. Entries include a plea for support to the city of Richmond to take care of its ‘destitute children’, letters to the editor of local newspapers, and poems for the birth of a child or death of a patron.Loose papers include a letter dated Jan 8th 1813, a bequeath request from William H. Hart for the placement of a Tombstone for Lydia Hart, a table of contents for various letters or sermons, a letter from William Hart to a friend from Richmond, and 2 loose undated papers of unknown authorship. The letter from William Hart speaks of the events of Lydia’s death, and inquiries about events taking place in Richmond

    1, 2-H shift in benzylchlorocarbene: isotope effect and influence of the solvent

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    Laser flash photolysis of 3-chloro-3-benzyldiazirine and 3-chloro-3-(phenyldideuteriomethyl)diazirine in isooctane over the 60 to -80-degrees-C temperature range gives rise to curved Arrhenius plots for both 1,2-H and 1,2-D migration in benzylchlorcarbene. The k(H)/k(D) values increase smoothly from 0.87 to 2.62 when the temperature increases from -60 to +30-degrees-C. The k(H)/k(D) value is approximately 4 for most of the temperatures studied if a solvent correction is applied. Quantum mechanical tunnelling or the influence of the solvent may be a possible explanation for these observations.PT: J; CR: BONNEAU R, 1989, J AM CHEM SOC, V111, P5973 BONNEAU R, 1992, J PHOTOCH PHOTOBIO A, V68, P97 DIX EJ, 1993, J AM CHEM SOC, V115, P10424 EVANSECK JD, 1990, J PHYS CHEM-US, V94, P5518 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 JACKSON JE, 1994, ADV CARBENE CHEM JONES M, 1980, REACTIVE INTERMEDIAT, V2 KIRMSE W, 1971, CARBENE CHEM LIU MTH, 1984, TETRAHEDRON, V40, P887 LIU MTH, 1990, J AM CHEM SOC, V112, P3915 LIU MTH, 1992, J PHOTOCH PHOTOBIO A, V63, P115 LIU MTH, 1992, J PHYS ORG CHEM, V15, P285 LIU MTH, 1994, RES CHEM INTERMEDIAT, V20, P195 MODARELLI DA, 1992, J AM CHEM SOC, V114, P7034 MOSS RA, 1992, TETRAHEDRON LETT, V33, P4287 MOSS RA, 1994, ADV CARBENE CHEM MUROV SL, 1973, HDB PHOTOCHEMISTRY NICKON A, 1993, ACCOUNTS CHEM RES, V26, P84 SALIS GA, 1968, J PHYS CHEM-US, V72, P752 SANDER W, 1994, UNPUB SCHAEFER HF, 1979, ACCOUNTS CHEM RES, V12, P288 SCHOLLER WW, 1989, HOUBEN WEYL METHODEN, P41 SHIMANOUCHI T, 1972, TABLES MOL VIBRATION, V1 SUGIYAMA MH, 1992, J AM CHEM SOC, V114, P966 WIERLACHER S, 1993, J AM CHEM SOC, V115, P8943; NR: 25; TC: 20; J9: J PHOTOCHEM PHOTOBIOL A-CHEM; PG: 5; GA: PV021Source type: Electronic(1
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