189 research outputs found
Alternatively certified teachers: A qualitative inquiry into their motivations, approaches to learning, and commitment to teaching.
Alternative teacher certification has evolved over the last twenty years as a response to real and perceived shortages of qualified teachers. The reduction of teacher certification requirements has been viewed by many as a solution to teacher shortage problems as well as a way to improve the quality of the teaching force by recruiting highly-skilled people from the private sector who have developed real-world experience with subject matter. Rather than arguing the merit of alternative certification, this study pursued an understanding of successful alternatively certified teachers in order to inform policy and practice.In this study, 18 alternatively certified teachers, identified by their principals as successful, were interviewed using a qualitative approach. Although this study reflects only a small sample of alternatively certified teachers in the state of Oklahoma, this study has addressed the questions of what were the common motivations of alternatively certified teachers, what were their approaches to learning how to teach, how were their professional identities developed, what kept them committed to the teaching profession, and to what do they attribute their perseverance and success. The study demonstrated that these alternatively certified teachers were searching for a career in which they could make a difference. They approached learning in a variety of ways but learned mostly from their interactions with colleagues through mentoring and professional development and through their classroom experience. Their professional identity developed over time but was related to their sense of efficacy in the classroom and affirmation from their peers. Many of the factors that kept them committed to teaching were the same factors that drew them to teaching in the first place---a sense of fulfillment and commitment to students. The major factor contributing to their success and perseverance was school climate, specifically collegiality and administrator support. This study also explored and challenged policy makers' and educators' prevailing assumptions regarding alternative certification
Fidelity protocol for the Action Success Knowledge (ASK) trial: A psychosocial intervention administered by speech and language therapists to prevent depression in people with post-stroke aphasia
Introduction: Treatment fidelity is a complex, multifaceted evaluative process which refers to whether a studied intervention was delivered as intended. Monitoring and enhancing fidelity is one recommendation of the TiDIER (Template for Intervention Description and Replication) checklist, as fidelity can inform interpretation and conclusions drawn about treatment effects. Despite the methodological and translational benefits, fidelity strategies have been used inconsistently within health behaviour intervention studies; in particular, within aphasia intervention studies, reporting of fidelity remains relatively rare. This paper describes the development of a fidelity protocol for the Action Success Knowledge (ASK) study, a current cluster randomised trial investigating an early mood intervention for people with aphasia (a language disability caused by stroke). Methods and analysis: A novel fidelity protocol and tool was developed to monitor and enhance fidelity within the two arms (experimental treatment and attention control) of the ASK study. The ASK fidelity protocol was developed based on the National Institutes of Health Behaviour Change Consortium fidelity framework. Ethics and dissemination: The study protocol was approved by the Darling Downs Hospital and Health Service Human Research Ethics Committee in Queensland, Australia under the National Mutual Acceptance scheme of multicentre human research projects. Specific ethics approval was obtained for those participating sites who were not under the National Mutual Agreement at the time of application. The monitoring and ongoing conduct of the research project is in line with requirements under the National Mutual Acceptance. On completion of the trial, findings from the fidelity reviews will be disseminated via publications and conference presentations. Trial registration number ACTRN12614000979651
The Large-scale Distribution of Cool Gas around Luminous Red Galaxies
We present a measurement of the correlation function between luminous red
galaxies and cool gas traced by Mg II \lambda \lambda 2796, 2803 absorption, on
scales ranging from about 30 kpc to 20 Mpc. The measurement is based on
cross-correlating the positions of about one million red galaxies at z~0.5 and
the flux decrements induced in the spectra of about 10^5 background quasars
from the Sloan Digital Sky Survey. We find that: (i) This galaxy-gas
correlation reveals a change of slope on scales of about 1 Mpc, consistent with
the expected transition from a dark matter halo dominated environment to a
regime where clustering is dominated by halo-halo correlations. Assuming that,
on average, the distribution of Mg II gas follows that of dark matter up to a
gas-to-mass ratio, we find the standard halo model to provide an accurate
description of the gas distribution over three orders of magnitude in scale.
Within this framework we estimate the average host halo mass of luminous red
galaxies to be about 10^{13.5} M_solar, in agreement with other methods. We
also find the Mg II gas-to-mass ratio around LRGs to be consistent with the
cosmic value estimated on Mpc scales. Combining our galaxy-gas correlation and
the galaxy-mass correlation function from galaxy-galaxy lensing analyses we can
directly measure the Mg II gas-to-mass ratio as a function of scale and reach
the same conclusion. (ii) From line-width estimates, we show that the velocity
dispersion of the gas clouds also shows the expected 1- and 2-halo behaviors.
On large scales the gas distribution follows the Hubble flow, whereas on small
scales we observe the velocity dispersion of the Mg II gas clouds to be lower
than that of collisionless dark matter particles within their host halo. This
is in line with the fact that cool clouds are subject to the pressure of the
virialized hot gas.Comment: 18 pages, 11 figures, 1 table, submitted to MNRA
New Neutrino Mass Bounds from Sloan Digital Sky Survey III Data Release 8 Photometric Luminous Galaxies
We present neutrino mass bounds using 900,000 luminous galaxies with
photometric redshifts measured from Sloan Digital Sky Survey III Data Release
Eight (SDSS DR8). The galaxies have photometric redshifts between
and , and cover 10,000 square degrees and thus probe a volume of
3Gpc, enabling tight constraints to be derived on the amount of
dark matter in the form of massive neutrinos. A new bound on the sum of
neutrino masses eV, at 95% confidence level (CL), is
obtained after combining our sample of galaxies, which we call "CMASS", with
WMAP 7 year Cosmic Microwave Background (CMB) data and the most recent
measurement of the Hubble parameter from the Hubble Space Telescope (HST). This
constraint is obtained with a conservative multipole range choice of in order to minimize non-linearities, and a free bias parameter in each
of the four redshift bins. We study the impact of assuming this linear galaxy
bias model using mock catalogs, and find that this model causes a small () bias in . For this reason, we also quote
neutrino bounds based on a conservative galaxy bias model containing
additional, shot noise-like free parameters. In this conservative case, the
bounds are significantly weakened, e.g. eV (95% confidence
level) for WMAP+HST+CMASS (). We also study the dependence
of the neutrino bound on multipole range ( vs ) and on which combination of data sets is included as a prior. The
addition of supernova and/or Baryon Acoustic Oscillation data does not
significantly improve the neutrino mass bound once the HST prior is included.
[abridged]Comment: 14 pages, 8 figures, 1 tabl
SDSS-III Baryon Oscillation Spectroscopic Survey data release 12 : galaxy target selection and large-scale structure catalogues
The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. The code used, designated mksample, is released with this paper.Publisher PDFPeer reviewe
Acoustic scale from the angular power spectra of SDSS-III DR8 photometric luminous galaxies
We measure the acoustic scale from the angular power spectra of the Sloan
Digital Sky Survey III (SDSS-III) Data Release 8 imaging catalog that includes
872,921 galaxies over ~ 10,000 deg^2 between 0.45<z<0.65. The extensive
spectroscopic training set of the Baryon Oscillation Spectroscopic Survey
(BOSS) luminous galaxies allows precise estimates of the true redshift
distributions of galaxies in our imaging catalog. Utilizing the redshift
distribution information, we build templates and fit to the power spectra of
the data, which are measured in our companion paper, Ho et al. 2011, to derive
the location of Baryon acoustic oscillations (BAO) while marginalizing over
many free parameters to exclude nearly all of the non-BAO signal. We derive the
ratio of the angular diameter distance to the sound horizon scale D_A/r_s=
9.212 + 0.416 -0.404 at z=0.54, and therefore, D_A= 1411+- 65 Mpc at z=0.54;
the result is fairly independent of assumptions on the underlying cosmology.
Our measurement of angular diameter distance D_A is 1.4 \sigma higher than what
is expected for the concordance LCDM (Komatsu et al. 2011), in accordance to
the trend of other spectroscopic BAO measurements for z >~ 0.35. We report
constraints on cosmological parameters from our measurement in combination with
the WMAP7 data and the previous spectroscopic BAO measurements of SDSS
(Percival et al. 2010) and WiggleZ (Blake et al. 2011). We refer to our
companion papers (Ho et al. 2011; de Putter et al. 2011) for investigations on
information of the full power spectrum.Comment: 16 pages, 14 figures, 3 tables, submitted to Ap
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Analysis of potential systematics
We analyze the density field of galaxies observed by the Sloan Digital Sky
Survey (SDSS)-III Baryon Oscillation Spectroscopic Survey (BOSS) included in
the SDSS Data Release Nine (DR9). DR9 includes spectroscopic redshifts for over
400,000 galaxies spread over a footprint of 3,275 deg^2. We identify,
characterize, and mitigate the impact of sources of systematic uncertainty on
large-scale clustering measurements, both for angular moments of the
redshift-space correlation function and the spherically averaged power
spectrum, P(k), in order to ensure that robust cosmological constraints will be
obtained from these data. A correlation between the projected density of stars
and the higher redshift (0.43 < z < 0.7) galaxy sample (the `CMASS' sample) due
to imaging systematics imparts a systematic error that is larger than the
statistical error of the clustering measurements at scales s > 120h^-1Mpc or k
< 0.01hMpc^-1. We find that these errors can be ameliorated by weighting
galaxies based on their surface brightness and the local stellar density. We
use mock galaxy catalogs that simulate the CMASS selection function to
determine that randomly selecting galaxy redshifts in order to simulate the
radial selection function of a random sample imparts the least systematic error
on correlation function measurements and that this systematic error is
negligible for the spherically averaged correlation function. The methods we
recommend for the calculation of clustering measurements using the CMASS sample
are adopted in companion papers that locate the position of the baryon acoustic
oscillation feature (Anderson et al. 2012), constrain cosmological models using
the full shape of the correlation function (Sanchez et al. 2012), and measure
the rate of structure growth (Reid et al. 2012). (abridged)Comment: Matches version accepted by MNRAS. Clarifications and references have
been added. See companion papers that share the "The clustering of galaxies
in the SDSS-III Baryon Oscillation Spectroscopic Survey:" titl
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The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 9 Spectroscopic Galaxy Sample
We present measurements of galaxy clustering from the Baryon Oscillation
Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III
(SDSS-III). These use the Data Release 9 (DR9) CMASS sample, which contains
264,283 massive galaxies covering 3275 square degrees with an effective
redshift z=0.57 and redshift range 0.43 < z < 0.7. Assuming a concordance
Lambda-CDM cosmological model, this sample covers an effective volume of 2.2
Gpc^3, and represents the largest sample of the Universe ever surveyed at this
density, n = 3 x 10^-4 h^-3 Mpc^3. We measure the angle-averaged galaxy
correlation function and power spectrum, including density-field reconstruction
of the baryon acoustic oscillation (BAO) feature. The acoustic features are
detected at a significance of 5\sigma in both the correlation function and
power spectrum. Combining with the SDSS-II Luminous Red Galaxy Sample, the
detection significance increases to 6.7\sigma. Fitting for the position of the
acoustic features measures the distance to z=0.57 relative to the sound horizon
DV /rs = 13.67 +/- 0.22 at z=0.57. Assuming a fiducial sound horizon of 153.19
Mpc, which matches cosmic microwave background constraints, this corresponds to
a distance DV(z=0.57) = 2094 +/- 34 Mpc. At 1.7 per cent, this is the most
precise distance constraint ever obtained from a galaxy survey. We place this
result alongside previous BAO measurements in a cosmological distance ladder
and find excellent agreement with the current supernova measurements. We use
these distance measurements to constrain various cosmological models, finding
continuing support for a flat Universe with a cosmological constant.Comment: 33 page
Neuronal interactions between mentalizing and action systems during indirect request processing
Human communication relies on the ability to process linguistic structure and to map words and utterances onto our environment. Furthermore, as what we communicate is often not directly encoded in our language (e.g., in the case of irony, jokes, or indirect requests), we need to extract additional cues to infer the beliefs and desires of our conversational partners. Although the functional interplay between language and the ability to mentalize has been discussed in theoretical accounts in the past, the neurobiological underpinnings of these dynamics are currently not well understood. Here, we address this issue using functional imaging (fMRI). Participants listened to question-reply dialogues. In these dialogues, a reply is interpreted as a direct reply, an indirect reply, or a request for action, depending on the question. We show that inferring meaning from indirect replies engages parts of the mentalizing network (mPFC) while requests for action also activate the cortical motor system (IPL). Subsequent connectivity analysis using Dynamic Causal Modelling (DCM) revealed that this pattern of activation is best explained by an increase in effective connectivity from the mentalizing network (mPFC) to the action system (IPL). These results are an important step towards a more integrative understanding of the neurobiological basis of indirect speech processing
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