2,448 research outputs found
A Multiple Measures Model for Documenting Teacher and Program Effectiveness
One of the most difficult challenges facing teacher educators is evaluating the knowledge, skills, and attributes necessary for professional growth and responsibility for teaching. Currently two viewpoints for preparing highly qualified teachers seem to be influencing policy. One view represented by Darling-Hammond’s research (1999), suggests that regulation of teacher education, state licensing, professional accountability, and compensation are important factors for strengthening teacher quality. A second view, offered by Chester Finn from research completed by the Thomas B. Fordham Foundation (cited in Berry, Hoke, and Hirsch, 2004), emphasizes less prescriptive paths such as alternative certification practices and aptitude testing to attract more qualified candidates to the profession. What seems to be established is that competent teachers are essential to the learning process. Sanders and Rivers (1998) found that effective teachers directly and positively impact the quality of teaching and, more importantly, student learning in classrooms. As a result, the stakes are high for students; their learning may be directly enhanced or damaged by the quality and effectiveness of their teachers’ practices. [excerpt
The SAMI Galaxy Survey: Mass as the Driver of the Kinematic Morphology–Density Relation in Clusters
We examine the kinematic morphology of early-type galaxies (ETGs) in eight galaxy clusters in the Sydney-AAO Multi-object Integral-field spectrograph Galaxy Survey. The clusters cover a mass range of 14.2 < log(M_(200)/M_☉) < 15.2 and we measure spatially resolved stellar kinematics for 315 member galaxies with stellar masses 10.0 <log(M_*/ M_☉) ⩽ 11.7 within 1 R_(200) of the cluster centers. We calculate the spin parameter, λ_R , and use this to classify the kinematic morphology of the galaxies as fast or slow rotators (SRs). The total fraction of SRs in the ETG population is F_(SR) = 0.14 ± 0.02 and does not depend on host cluster mass. Across the eight clusters, the fraction of SRs increases with increasing local overdensity. We also find that the slow-rotator fraction increases at small clustercentric radii (R_(cl) < 0.3R_(200)), and note that there is also an increase in the slow-rotator fraction at R_(cl) ~ 0.6 R_(200). The SRs at these larger radii reside in the cluster substructure. We find that the strongest increase in the slow-rotator fraction occurs with increasing stellar mass. After accounting for the strong correlation with stellar mass, we find no significant relationship between spin parameter and local overdensity in the cluster environment. We conclude that the primary driver for the kinematic morphology–density relationship in galaxy clusters is the changing distribution of galaxy stellar mass with the local environment. The presence of SRs in the substructure suggests that the cluster kinematic morphology–density relationship is a result of mass segregation of slow-rotating galaxies forming in groups that later merge with clusters and sink to the cluster center via dynamical friction
Galaxy And Mass Assembly (GAMA): Resolving the role of environment in galaxy evolution
We present observations of 18 galaxies from the Galaxy And Mass Assembly (GAMA)
survey made with the SPIRAL optical integral field unit (IFU) on the Anglo- Australian Telescope. The galaxies are selected to have a narrow range in stellar mass
(6 × 109M
< M∗
< 2 × 1010M
) in order to focus on the effects of environment.
Local galaxy environments are measured quantitatively using 5th nearest neighbour surface densities. We find that the total star formation rates (SFR) measured from the IFU data are consistent with total SFRs measured from aperture correcting either GAMA or Sloan Digital Sky Survey single-fibre observations. The mean differences are SFRGAMA/SFRIFU = 1.26 ± 0.23, σ = 0.90 and for the Sloan Digital Sky Sur- vey we similarly find SFRBrinchmann/SFRIFU = 1.34 ± 0.17, σ = 0.67. Examining the relationships with environment, we find off-centre and clumpy Hα emission is not sig- nificantly dependent on environment, being present in 2/7 (29+20 per cent) galaxies in high-density environments (> 0.77 Mpc−2), and 5/11 (45+15 per cent) galaxies in low-density environments (< 0.77 Mpc−2). We find a weak but not significant relationship
of the total star formation rates of star-forming galaxies with environment. Due to the size of our sample and the scatter observed we do not draw a definitive conclusion about a possible SFR dependence on environment. Examining the spatial distribution of the Hα emission, we find no evidence for a change in shape or amplitude of the ra- dial profile of star-forming galaxies with environment. If these observations are borne out in larger samples this would infer that any environment-driven star-formation sup- pression must either act very rapidly (the ‘infall-and-quench’ model) or that galaxies must evolve in a density-dependent manner (an ‘in-situ evolution’ model).Web of Scienc
Nuclear retention of IL-1 alpha by necrotic cells: A mechanism to dampen sterile inflammation
Sterile inflammation is a host response to tissue injury that is mediated by damage-associated molecular patterns (DAMPs) released from dead cells. Sterile inflammation worsens damage in a number of injury paradigms. The pro-inflammatory cytokine interleukin-1α (IL-1α) is reported to be a DAMP released from dead cells, and is known to exacerbate brain injury caused by stroke. In the brain, IL-1α is produced by microglia, the resident brain macrophages. We found that IL-1α is actively trafficked to the nuclei of microglia, and hence tested the hypothesis that trafficking of IL-1α to the nucleus would inhibit its release following necrotic cell death, limiting sterile inflammation. Microglia subjected to oxygen-glucose deprivation (OGD) died via necrosis. Under these conditions, microglia expressing nuclear IL-1α released significantly less IL-1α than microglia with predominantly cytosolic IL-1α. The remaining IL-1α was immobilised in the nuclei of the dead cells. Thus, nuclear retention of IL-1α may serve to limit inflammation following cell death
Galaxy And Mass Assembly (GAMA): end of survey report and data release 2
The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ˜286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm-1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sérsic fits, stellar masses, Hα-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72 225 objects in total). The data base serving these data is available at http://www.gama-survey.org/
The impact of receiving a diagnosis of Non-Epileptic Attack Disorder (NEAD): a systematic review
Background: Clinicians have reported observations of the immediate cessation of non-epileptic attacks after the diagnosis of NEAD is presented.
Objective: The purpose of this systematic review was to examine the impact of receiving a diagnosis of NEAD.
Search strategy: A literature search across the databases Medline, PsycINFO, EMBASE, and CINAHL, and additional hand searching, identified 6 original studies meeting criteria for the review.
Selection Criteria: Included studies were original peer-reviewed articles investigating the impact of receiving a diagnosis of NEAD on adult populations with at least one outcome measured pre and post-diagnosis.
Analysis: The studies were assessed for methodological quality, including biases. This assessment was developed to include criteria specific to research regarding NEAD and diagnosis.
Results: Six identified studies, with a total of 153 NEAD participants, examined the impact of receiving a diagnosis on seizure frequency. Two of the six also examined the impact on health-related quality of life. The findings were inconsistent, with approximately half the participants experiencing seizure reduction or cessation post-diagnosis. Diagnosis appeared to have no significant impact on health-related quality of life. The overall evidence lacked quality, particularly in study design and statistical rigour.
Conclusions: Mixed results and a lack of high quality evidence was found. Concerns are considered regarding the appropriateness of seizure frequency as the primary outcome measure and the use of epilepsy control groups. Indications for future research include: measuring more meaningful outcomes, using larger samples and power calculations, and ensuring consistent and standard methods for communicating the diagnosis and recording outcomes
H-ATLAS/GAMA and HeViCS – dusty early-type galaxies in different environments
The Herschel Space Observatory has had a tremendous impact on the study of extragalactic dust. Specifically, early-type galaxies (ETG) have been the focus of several studies. In this paper, we combine results from two Herschel studies – a Virgo cluster study Herschel Virgo Cluster Survey (HeViCS) and a broader, low-redshift Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS)/Galaxy and Mass Assembly (GAMA) study – and contrast the dust and associated properties for similar mass galaxies. This comparison is motivated by differences in results exhibited between multiple Herschel studies of ETG. A comparison between consistent modified blackbody derived dust mass is carried out, revealing strong differences between the two samples in both dust mass and dust-to-stellar mass ratio. In particular, the HeViCS sample lacks massive ETG with as high a specific dust content as found in H-ATLAS. This is most likely connected with the difference in environment for the two samples. We calculate nearest neighbour environment densities in a consistent way, showing that H-ATLAS ETG occupy sparser regions of the local Universe, whereas HeViCS ETG occupy dense regions. This is also true for ETG that are not Herschel-detected but are in the Virgo and GAMA parent samples. Spectral energy distributions are fit to the panchromatic data. From these, we find that in H-ATLAS the specific star formation rate anticorrelates with stellar mass and reaches values as high as in our Galaxy. On the other hand HeViCS ETG appear to have little star formation. Based on the trends found here, H-ATLAS ETG are thought to have more extended star formation histories and a younger stellar population than HeViCS ETG
Galaxy And Mass Assembly (GAMA) : The mechanisms for quiescent galaxy formation at z<1
© 2016 The Authors. One key problem in astrophysics is understanding how and why galaxies switch off their star formation, building the quiescent population that we observe in the local Universe. From the Galaxy And Mass Assembly and VIsible MultiObject Spectrograph Public Extragalactic Redshift surveys, we use spectroscopic indices to select quiescent and candidate transition galaxies.We identify potentially rapidly transitioning post-starburst (PSB) galaxies and slower transitioning green-valley galaxies. Over the last 8Gyr, the quiescent population has grown more slowly in number density at high masses (M * > 10 11 M ⊙ ) than at intermediate masses (M * > 10 10.6 M ⊙ ). There is evolution in both the PSB and green-valley stellar mass functions, consistent with higher mass galaxies quenching at earlier cosmic times.At intermediatemasses (M * > 10 10.6 M ⊙ ), we find a green-valley transition time-scale of 2.6 Gyr. Alternatively, at z ~ 0.7, the entire growth rate could be explained by fast-quenching PSB galaxies, with a visibility time-scale of 0.5 Gyr. At lower redshift, the number density of PSBs is so low that an unphysically short visibility window would be required for them to contribute significantly to the quiescent population growth. The importance of the fast-quenching route may rapidly diminish at z 10 11 M ⊙ ), there is tension between the large number of candidate transition galaxies compared to the slow growth of the quiescent population. This could be resolved if not all high-mass PSB and green-valley galaxies are transitioning from star forming to quiescent, for example if they rejuvenate out of the quiescent population following the accretion of gas and triggering of star formation, or if they fail to completely quench their star formation
Galaxy And Mass Assembly (GAMA): growing up in a bad neighbourhood - how do low-mass galaxies become passive?
Both theoretical predictions and observations of the very nearby Universe
suggest that low-mass galaxies (log[M/M]<9.5) are likely
to remain star-forming unless they are affected by their local environment. To
test this premise, we compare and contrast the local environment of both
passive and star-forming galaxies as a function of stellar mass, using the
Galaxy and Mass Assembly survey. We find that passive fractions are higher in
both interacting pair and group galaxies than the field at all stellar masses,
and that this effect is most apparent in the lowest mass galaxies. We also find
that essentially all passive log[M/M]<8.5 galaxies are
found in pair/group environments, suggesting that local interactions with a
more massive neighbour cause them to cease forming new stars. We find that the
effects of immediate environment (local galaxy-galaxy interactions) in forming
passive systems increases with decreasing stellar mass, and highlight that this
is potentially due to increasing interaction timescales giving sufficient time
for the galaxy to become passive via starvation. We then present a simplistic
model to test this premise, and show that given our speculative assumptions, it
is consistent with our observed results.Comment: 20 pages, 12 figures, Accepted to MNRA
How young people from culturally and linguistically diverse backgrounds experience mental health: some insights for mental health nurses
This article reports on a part of a study which looked at the mental health of
culturally and linguistically diverse (CALD) young people. The research sought to learn
from CALD young people, carers, and service providers experiences relevant to the
mental health of this group of young people. The ultimate goal was to gain insights that
would inform government policy, service providers, ethnic communities and most
importantly the young people themselves. To this end, qualitative interviews were
undertaken with 123 CALD young people, 41 carers and 14 mental health service
providers in Queensland, Western Australia and South Australia.
Only one aspect of the study will be dealt with here, namely the views of the
young CALD participants, which included risk factors, coping strategies and
recommendations about how they could be supported in their struggle to maintain
mental health. One of the most important findings of the study relates to the resilience
of these young people and an insight into the strategies that they used to cope. The
efforts of these young people to assist us in our attempts to understand their situation
deserve to be rewarded by improvements in the care that we provide. To this end this
article sets out to inform mental health nurses of the results of the study so that they will
be in a position to better understand the needs and strengths of their CALD clients and
be in a better position to work effectively with them
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