1,736 research outputs found

    A systematic review of interactions in pedagogical approaches with reported outcomes for the academic and social inclusion of pupils with special educational needs

    Get PDF
    From the introduction/background: The growing demand for inclusive practices within mainstream schools has resulted in classroom teachers having to take direct responsibility for the individual learning needs of all pupils within the setting, and reduced the expectation that support staff should be the primary practitioners for children with special educational needs (SEN). The belief in a need for special pedagogical approaches for these children has also been widely critiqued (e.g. Norwich and Lewis, 2001; Hart, 1996) and there has been a growing focus upon the teaching practices that can be, and are, more broadly used by mainstream practitioners. Central to all these approaches are the interactions that both create the learning context and operate within it

    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

    Get PDF
    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

    Level crossing in the three-body problem for strongly interacting fermions in a harmonic trap

    Full text link
    We present a solution of the three-fermion problem in a harmonic potential across a Feshbach resonance. We compare the spectrum with that of the two-body problem and show that it is energetically unfavorable for the three fermions to occupy one lattice site rather than two. We also demonstrate the existence of an energy level crossing in the ground state with a symmetry change of its wave function, suggesting the possibility of a phase transition for the corresponding many-body case.Comment: 5 pages, 6 figures, typos corrected, references adde

    Proximity-Induced Superconductivity at Non-Helical Topological Insulator Interfaces

    Get PDF
    We study how non-helical spin textures at the boundary between a topological insulator (TI) and a superconductor (SC) affect the proximity-induced superconductivity of the TI interface state. We consider TIs coupled to both spin-singlet and spin-triplet SCs, and show that for the spin-triplet parent SCs the resulting order parameter induced onto the interface state sensitively depends on the symmetries which are broken at the TI-SC boundary. For chiral spin-triplet parent SCs, we find that nodal proximity-induced superconductivity emerges when there is broken twofold rotational symmetry which forces the spins of the non-helical topological states to tilt away from the interface plane. We furthermore show that the Andreev conductance of lateral heterostructures joining TI-vacuum and TI-SC interfaces yields experimental signatures of the reduced symmetries of the interface states.Comment: 5 pages, 2 figure

    Using off-diagonal confinement as a cooling method

    Get PDF
    In a recent letter [Phys. Rev. Lett. 104, 167201 (2010)] we proposed a new confining method for ultracold atoms on optical lattices, based on off-diagonal confinement (ODC). This method was shown to have distinct advantages over the conventional diagonal confinement (DC) that makes use of a trapping potential, including the existence of pure Mott phases and highly populated condensates. In this paper we show that the ODC method can also lead to temperatures that are smaller than with the conventional DC method, depending on the control parameters. We determine these parameters using exact diagonalizations for the hard-core case, then we extend our results to the soft-core case by performing quantum Monte Carlo (QMC) simulations for both DC and ODC systems at fixed temperatures, and analysing the corresponding entropies. We also propose a method for measuring the entropy in QMC simulations.Comment: 6 pages, 6 figure

    Imaging of the Stellar Population of IC10 with Laser Guide Star Adaptive Optics and the Hubble Space Telescope

    Get PDF
    We present adaptive optics (AO) images of the central starburst region of the dwarf irregular galaxy IC10. The Keck 2 telescope laser guide star was used to achieve near diffraction-limited performance at H and K' (Strehls of 18% and 32%, respectively). The images are centered on the putative Wolf-Rayet (W-R) object [MAC92]24. We combine our AO images with F814W data from HST. By comparing the K' vs. [F814W]-K' color-magnitude diagram (CMD) with theoretical isochrones, we find that the stellar population is best represented by at least two bursts of star formation, one ~ 10 Myr ago and one much older (150-500 Myr). Young, blue stars are concentrated in the vicinity of [MAC92]24. This population represents an OB association with a half-light radius of about 3 pc. We resolve the W-R object [MAC92]24 into at least six blue stars. Four of these components have near-IR colors and luminosities that make them robust WN star candidates. By matching the location of C-stars in the CMD with those in the SMC we derive a distance modulus for IC10 of about 24.5 mag. and a foreground reddening of E(B-V) = 0.95. We find a more precise distance by locating the tip of the giant branch in the F814W, H, and K' luminosity functions. We find a weighted mean distance modulus of 24.48 +/- 0.08. The systematic error in this measurement, due to a possible difference in the properties of the RGB populations in IC10 and the SMC, is +/- 0.16 mag.Comment: 13 pages, 13 figures, ApJ in pres

    Oxidative capacity of the Mexico City atmosphere ? Part 1: A radical source perspective

    No full text
    International audienceA detailed analysis of OH, HO2 and RO2 radical sources is presented for the near field photochemical regime inside the Mexico City Metropolitan Area (MCMA). During spring of 2003 (MCMA-2003 field campaign) an extensive set of measurements was collected to quantify time resolved ROx (sum of OH, HO2, RO2) radical production rates from day- and nighttime radical sources. The Master Chemical Mechanism (MCMv3.1) was constrained by measurements of (1) concentration time-profiles of photosensitive radical precursors, i.e., nitrous acid (HONO), formaldehyde (HCHO), ozone (O3), glyoxal (CHOCHO), and other oxygenated volatile organic compounds (OVOCs); (2) respective photolysis-frequencies (J-values); (3) concentration time-profiles of alkanes, alkenes, and aromatic VOCs (103 compound are treated) and oxidants, i.e., OH- and NO3 radicals, O3; and (4) NO, NO2, meteorological and other parameters. The ROx production rate was calculated directly from these observations; MCM was used to estimate further ROx production from unconstrained sources, and express overall ROx production as OH-equivalents (i.e., taking into account the propagation efficiencies of RO2 and HO2 radicals into OH radicals). Daytime radical production is found to be about 10-25 times higher than at night; it does not track the abundance of sunlight. 12-h average daytime contributions of individual sources are: HCHO and O3 photolysis, each about 20%; O3/alkene reactions and HONO photolysis, each about 15%; unmeasured sources about 30%. While the direct contribution of O3/alkene reactions appears to be moderately small, source-apportionment of ambient HCHO and HONO identifies O3/alkene reactions as being largely responsible for jump-starting photochemistry about one hour after sunrise. The peak radical production is found to be higher than in any other urban influenced environment studied to date; further, differences exist in the timing of radical production. Our measurements and analysis comprise a database that enables testing of the representation of radical sources in photochemical models. Since the photochemical processing of pollutants is radical-limited in the MCMA, our analysis identifies the drivers for such processing. Three pathways are identified by which reductions in VOC emissions induce reductions in peak concentrations of secondary pollutants, such as O3 and secondary organic aerosol (SOA)

    Projected climate change impacts on upland heaths in Ireland

    Get PDF
    Heathland habitats in Ireland occur primarily in an oceanic setting which is strongly influenced by changes in the climate. As a consequence of the oceanic environment, Ireland has a high proportion of the northern Atlantic wet and alpine and boreal heaths of high conservation value within Europe. Future climate change is widely expected to place additional pressure on these systems. Seven bioclimatic envelope modelling techniques implemented in the BIOMOD modelling framework were used to model Wet and Alpine and Boreal heath distributions in Ireland. The 1961 to 1990 baseline models closely matched the observed distribution, and emphasise the strong dependency on climate. Mean winter precipitation, mean winter temperature and elevation were found to be important model components. The fitted models discrimination ability was assessed using the area under the curve (range 0.874 to 0.929, Wet heath; 0.858 to 0.936, Alpine and Boreal heath) of a receiver operating characteristic plot; the true skill statistic (range 0.648 to 0.713, Wet heath; 0.666 to 0.737, Alpine and Boreal heath); and Cohen’s kappa (range 0.652 to 0.714, Wet heath; 0.641 to 0.738, Alpine and Boreal heath). A BIOMOD ensemble prediction from all the models was used to project changes based on a climate change scenario for 2031 to 2060 dynamically downscaled from the Hadley Centre HadCM3-Q16 global climate model. The climate change projections for the individual models change markedly from the consistent baseline predictions. Projected climate space losses (gains) from the BIOMOD consensus model are -40.84% (limited expansion) and -10.38% (full expansion) for Wet heath; and -18.31% (limited expansion) and +28.17% (full expansion) for Alpine and Boreal heath. Although the consensus models project gains in climate space for both habitats in other parts of the country, new habitat formation in these areas is unlikely as current (and hence near future) land use and other conditions are not likely to favour expansion

    Oxidative capacity of the Mexico City atmosphere - Part 2: A ROx radical cycling perspective

    Get PDF
    A box model using measurements from the Mexico City Metropolitan Area study in the spring of 2003 (MCMA-2003) is presented to study oxidative capacity (our ability to predict OH radicals) and ROx (ROx=OH+HO2+RO2+RO) radical cycling in a polluted (i.e., very high NOx=NO+NO2) atmosphere. Model simulations were performed using the Master Chemical Mechanism (MCMv3.1) constrained with 10 min averaged measurements of major radical sources (i.e., HCHO, HONO, O3, CHOCHO, etc.), radical sink precursors (i.e., NO, NO2, SO2, CO, and 102 volatile organic compounds (VOC)), meteorological parameters (temperature, pressure, water vapor concentration, dilution), and photolysis frequencies. Modeled HOx (=OH+HO2) concentrations compare favorably with measured concentrations for most of the day; however, the model under-predicts the concentrations of radicals in the early morning. This "missing reactivity" is highest during peak photochemical activity, and is least visible in a direct comparison of HOx radical concentrations. We conclude that the most likely scenario to reconcile model predictions with observations is the existence of a currently unidentified additional source for RO2 radicals, in combination with an additional sink for HO2 radicals that does not form OH. The true uncertainty due to "missing reactivity" is apparent in parameters like chain length. We present a first attempt to calculate chain length rigorously i.e., we define two parameters that account for atmospheric complexity, and are based on (1) radical initiation, n(OH), and (2) radical termination, ω. We find very high values of n(OH) in the early morning are incompatible with our current understanding of ROx termination routes. We also observe missing reactivity in the rate of ozone production (P(O3)). For example, the integral amount of ozone produced could be under-predicted by a factor of two. We argue that this uncertainty is partly accounted for in lumped chemical codes that are optimized to predict ozone concentrations; however, these codes do not reflect the true uncertainty in oxidative capacity that is relevant to other aspects of air quality management, such as the formation of secondary organic aerosol (SOA). Our analysis highlights that apart from uncertainties in emissions, and meteorology, there is an additional major uncertainty in chemical mechanisms that affects our ability to predict ozone and SOA formation with confidence.National Science Foundation (U.S.) (ATM-0528227)United States. Dept. of Energy (Grant DE-FG02-0563980)Alliance for Global SustainabilityHenry & Camille Dreyfus FoundationAlexander von Humboldt-StiftungNational Science Foundation (U.S.) (CAREER award ATM-0847793
    • …
    corecore