100 research outputs found

    The Effect of Token Economies on Student Behavior in the Preschool Classroom: A Meta-Analysis

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    There has been a recent push in the literature to identify and use more evidence-based practices for positive behavioral supports for challenging student behaviors in the classroom environment. Further, interest in targeting early education environments such as preschool has been growing given the persistence of behavioral difficulties in the absence of early and effective intervention (Campbell & Ewing, 1990; Kazdin, 1987; Powell et al., 2006; Stormont, 2002). Two previous meta-analyses (Maggin et al., 2011; Soares et al., 2016) provided some initial support for effectiveness of token economies with challenging student behavior; however, the inclusion of the preschool setting was limited and both studies used older versions of design standards to evaluate the quality of studies in the literature. The present study served to extend those meta-analyses by targeting preschool classrooms. Further, the current study included the most recent What Works Clearinghouse Design Standards to evaluate whether token economies meet criteria as an evidence-based practice. Ten studies were included in the final analyses. Two sets of effect sizes were calculated: Baseline-Corrected Tau and Hedge’s g. An omnibus effect size showed an overall large effect; however, similar to previous meta-analyses, several methodological concerns were identified. Moderator analyses for several variables were conducted; however, no moderator analyses were significant. Limitations and future directions were discussed

    Striking reduction of amyloid plaque burden in an Alzheimer's mouse model after chronic administration of carmustine

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    BACKGROUND: Currently available therapies for Alzheimer's disease (AD) do not treat the underlying cause of AD. Anecdotal observations in nursing homes from multiple studies strongly suggest an inverse relationship between cancer and AD. Therefore, we reasoned that oncology drugs may be effective against AD. METHODS: We screened a library of all the FDA-approved oncology drugs and identified bis-chloroethylnitrosourea (BCNU or carmustine) as an effective amyloid beta (Aβ) reducing compound. To quantify Aβ levels, Chinese hamster ovary (CHO) cells stably expressing amyloid precursor protein 751WT (APP751WT) called 7WD10 cells were exposed to different concentrations of BCNU for 48 hours and the conditioned media were collected. To detect Aβ the conditioned media were immunoprecipitated with Ab9 antibody and subjected to immunoblot detection. Amyloid plaques were quantified in the brains of a mouse model of AD after chronic exposure to BCNU by thoflavin S staining. RESULTS: BCNU decreased normalized levels of Aβ starting from 5 μM by 39% (P < 0.05), 10 μM by 51% (P < 0.01) and 20 μM by 63% (P < 0.01) in CHO cells compared to a control group treated with butyl amine, a structural derivative of BCNU. Interestingly, soluble amyloid precursor protein α (sAPPα) levels were increased to 167% (P < 0.01) at 0.5 μM, 186% (P < 0.05) at 1 μM, 204% (P < 0.01) at 5 μM and 152% (P < 0.05) at 10 μM compared to untreated cells. We also tested the effects of 12 structural derivatives of BCNU on Aβ levels, but none of them were as potent as BCNU. BCNU treatment at 5 μM led to an accumulation of immature APP at the cell surface resulting in an increased ratio of surface to total APP by 184% for immature APP, but no change in mature APP. It is also remarkable that BCNU reduced Aβ generation independent of secretases which were not altered up to 40 μM. Interestingly, levels of transforming growth factor beta (TGFβ) were increased at 5 μM (43%, P < 0.05), 10 μM (73%, P < 0.01) and 20 μM (92%, P < 0.001). Most significantly, cell culture results were confirmed in vivo after chronic administration of BCNU at 0.5 mg/kg which led to the reduction of Aβ40 by 75% and amyloid plaque burden by 81%. Conversely, the levels of sAPPα were increased by 45%. CONCLUSIONS: BCNU reduces Aβ generation and plaque burden at non-toxic concentrations possibly through altered intracellular trafficking and processing of APP. Taken together these data provided unequivocal evidence that BCNU is a potent secretase-sparing anti-Aβ drug. See related commentary article here http://www.biomedcentral.com/1741-7015/11/8

    Political ideology and American intergroup discrimination: A patriotism perspective

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    In this research we take the theoretical approach advocated by Greenwald and Pettigrew (2014) and demonstrate the powerful role of ingroup favoritism, rather than hostility, in American intergroup biases. Specifically, we take a novel perspective to understanding the relationship between political ideology and discrimination against ethnic-minority Americans by focusing on the role of patriotism. Across three studies, we show that political ideology is a strong predictor of resource allocation biases and this effect is mediated by American patriotism and not by prejudice or nationalism. Conservatives report greater levels of patriotism than liberals, and patriotism is associated with donating more to American, as opposed to ethnic-minority American, organizations. We further show that the link between patriotism and partiality to the national group is mediated by stronger ‘American=White’ associations. These findings have important implications for intergroup relations and diversity-related policy issues in the United States

    Between the Post and the Com-Post:Examining the Postdigital ‘Work’ of a Prefix

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    In examining the work of the prefix ‘post’, we aim to contribute to the current postdigital dialogue. Our paper does not provide a rationale for the use of ‘postdigital’ in the title of this journal: that has been thoroughly explored elsewhere. We want instead to consider the work the prefix might do. We look at ‘post’, as it appears to ‘act’ in the terms of ‘postmodernism’ and ‘posthumanism’, suggesting that modernism and humanism are in need of questioning and reworking. We also examine what gets ‘post-ed’, or sometimes ‘com-posted’. (Com- is another interesting prefix, meaning ‘with’.) We then consider how these inquiries inform our understanding of a ‘postdigital reality’ that humans now inhabit. We understand this as a space of learning, struggle, and hope, where ‘old’ and ‘new’ media are now ‘cohabiting artefacts’ that enmesh with the economy, politics and culture. In entering this postdigital age, there really is no turning back from a convergence of the traditional and the digital. However, this is not simply a debate about technological and non-technological media. The postdigital throws up new challenges and possibilities across all aspects of social life. We believe this opens up new avenues too, for considering ways that discourse (language-in-use) shapes how we experience the postdigital

    Supporting Less-Proficent Writers through Linguistically-Aware Teaching

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    This is the author accepted manuscript. The final version is available from Taylor & Francis (Routledge) via the DOI in this record.Whilst historically there has been a widespread consensus that teaching grammar has no impact on students’ attainment in writing, more recent research suggests that where a functionally-oriented approach to grammar is meaningfully embedded within the teaching of writing, significant improvements in writing can be secured. A recent study ((Myhill et al 2012), using a functionally-oriented approach, which found a statistically significant positive effect of such an approach, also found that the approach appeared to benefit higher-attaining writers more than lower-attaining writers. The study reported here set out to investigate specifically whether functionally-oriented approach to teaching grammar in the context of writing might support less proficient writers. A quasi-experimental design was adopted, repeating the principles of the parent study but with the intervention adapted to meet the identified writing needs of less proficient writers. The statistical analysis indicated a positive effect for the intervention group (p<0.05), and an effect size of 0.33 on students’ sentence structure and punctuation. The study demonstrates that explicit attention to grammar within the teaching of writing can support learners in developing their writing, but taken with the parent study, it also highlights that pedagogical choices need to be well-matched to writers’ needs.This parent study referred to in this article was supported by the Economic and Social Research Council.Funding Agency under Grant ES/FO15313/1. The study reported in this article was funded by Pearson

    Collective Power to Create Political Change: Increasing the Political Efficacy and Engagement of Social Workers

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    Because social workers are called to challenge social injustices and create systemic change to support the well-being of individuals and communities, it is essential that social workers develop political efficacy: belief that the political system can work and they can influence the system. This study explored the impact of an intensive political social work curriculum on political efficacy and planned political engagement among social work students and practitioners. The findings suggest this model of delivering a political social work curriculum effectively increases internal, external, and overall political efficacy, and that increasing political efficacy has promise for increasing future political engagement

    Interpreting the Si II and C II line spectra from the COS Legacy Spectroscopic SurveY using a virtual galaxy from a high-resolution radiation-hydrodynamic simulation

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    Observations of low-ionization state (LIS) metal lines provide crucial insights into the interstellar medium of galaxies, yet, disentangling the physical processes responsible for the emerging line profiles is difficult. This work investigates how mock spectra generated using a single galaxy in a radiation-hydrodynamical simulation can help us interpret observations of a real galaxy. We create 22,500 C II and Si II spectra from the virtual galaxy at different times and through multiple lines of sight and compare them with the 45 observations of low-redshift star-forming galaxies from the COS Legacy Spectroscopic SurveY (CLASSY). We find that the mock profiles provide accurate replicates to the observations of 38 galaxies with a broad range of stellar masses (10610^6 to 10910^9 MM_\odot) and metallicities (0.02 to 0.55 ZZ_\odot). Additionally, we highlight that aperture losses explain the weakness of the fluorescent emission in several CLASSY spectra and must be accounted for when comparing simulations to observations. Overall, we show that the evolution of a single simulated galaxy can produce a large diversity of spectra whose properties are representative of galaxies of comparable or smaller masses. Building upon these results, we explore the origin of the continuum, residual flux, and fluorescent emission in the simulation. We find that these different spectral features all emerge from distinct regions in the galaxy's ISM, and their characteristics can vary as a function of the viewing angle. While these outcomes challenge simplified interpretations of down-the-barrel spectra, our results indicate that high-resolution simulations provide an optimal framework to interpret these observations.Comment: Accepted for publication in Ap

    CLASSY VIII: Exploring the Source of Ionization with UV ISM diagnostics in local High-zz Analogs

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    In the current JWST era, rest-frame UV spectra play a crucial role in enhancing our understanding of the interstellar medium (ISM) and stellar properties of the first galaxies in the epoch of reionization (EoR, z>6z>6). Here, we compare well-known and reliable optical diagrams sensitive to the main ionization source (i.e., star formation, SF; active galactic nuclei, AGN; shocks) to UV counterparts proposed in the literature - the so-called ``UV-BPT diagrams'' - using the HST COS Legacy Archive Spectroscopic SurveY (CLASSY), the largest high-quality, high-resolution and broad-wavelength range atlas of far-UV spectra for 45 local star-forming galaxies. In particular, we explore where CLASSY UV line ratios are located in the different UV diagnostic plots, taking into account state-of-the-art photoionization and shock models and, for the first time, the measured ISM and stellar properties (e.g., gas-phase metallicity, ionization parameter, carbon abundance, stellar age). We find that the combination of C III] λλ\lambda\lambda1907,9 He II λ1640\lambda1640 and O III] λ\lambda1666 can be a powerful tool to separate between SF, shocks and AGN at sub-solar metallicities. We also confirm that alternative diagrams without O III] λ\lambda1666 still allow us to define a SF-locus with some caveats. Diagrams including C IV λλ\lambda\lambda1548,51 should be taken with caution given the complexity of this doublet profile. Finally, we present a discussion detailing the ISM conditions required to detect UV emission lines, visible only in low gas-phase metallicity (12+log(O/H) 8.3\lesssim8.3) and high ionization parameter (log(UU) 2.5\gtrsim-2.5) environments. Overall, CLASSY and our UV toolkit will be crucial in interpreting the spectra of the earliest galaxies that JWST is currently revealing.Comment: 31 pages, submitted to ApJ, comments welcom

    The COS Legacy Archive Spectroscopy SurveY (CLASSY) Treasury Atlas

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    Far-ultraviolet (FUV; ~1200-2000 angstroms) spectra are fundamental to our understanding of star-forming galaxies, providing a unique window on massive stellar populations, chemical evolution, feedback processes, and reionization. The launch of JWST will soon usher in a new era, pushing the UV spectroscopic frontier to higher redshifts than ever before, however, its success hinges on a comprehensive understanding of the massive star populations and gas conditions that power the observed UV spectral features. This requires a level of detail that is only possible with a combination of ample wavelength coverage, signal-to-noise, spectral-resolution, and sample diversity that has not yet been achieved by any FUV spectral database. We present the COS Legacy Spectroscopic SurveY (CLASSY) treasury and its first high level science product, the CLASSY atlas. CLASSY builds on the HST archive to construct the first high-quality (S/N_1500 >~ 5/resel), high-resolution (R~15,000) FUV spectral database of 45 nearby (0.002 < z < 0.182) star-forming galaxies. The CLASSY atlas, available to the public via the CLASSY website, is the result of optimally extracting and coadding 170 archival+new spectra from 312 orbits of HST observations. The CLASSY sample covers a broad range of properties including stellar mass (6.2 < logM_star(M_sol) < 10.1), star formation rate (-2.0 < log SFR (M_sol/yr) < +1.6), direct gas-phase metallicity (7.0 < 12+log(O/H) < 8.8), ionization (0.5 < O_32 < 38.0), reddening (0.02 < E(B-V < 0.67), and nebular density (10 < n_e (cm^-3) < 1120). CLASSY is biased to UV-bright star-forming galaxies, resulting in a sample that is consistent with z~0 mass-metallicity relationship, but is offset to higher SFRs by roughly 2 dex, similar to z >~2 galaxies. This unique set of properties makes the CLASSY atlas the benchmark training set for star-forming galaxies across cosmic time.Comment: Accepted for publication in Ap
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