264 research outputs found

    Cultural and academic adjustment of refugee youth: Introduction to the special issue

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    © 2017 Elsevier Ltd In this introduction to the IJIR special issue on refugee youth in academic settings, the editors sought manuscripts that examined both challenges and effective practices in countries of temporary and permanent refugee resettlement. We welcomed diverse methodological approaches and empirical work at all levels and types of education (formal, non-formal, and informal). Our final selections do not fully represent the field of refugee education, as eight of the nine are studies in third countries of permanent resettlement, a designation received by only about one percent of the total refugee population. Perspectives came from the social sciences: psychology, sociology, anthropology, and sociolinguistic disciples. Themes of the articles fall into two broad categories: 1) educational challenges due to trauma, acculturation stressors, and educational issues; and 2) educational practices intended to address some of these challenges. Although the resettlement category is the smallest of the UNHCR's “durable solutions,” the authors present important findings to support refugee students’ success. These have to do with collaborative processes, issues of identity, the use of social media, and teacher training in multicultural and language support. In considering future work in this field, we conclude that dimensions of justice need to be more fully examined in other refugee solutions (such as repatriation and local integration in the first country of refuge). We recommend that more research be conducted on the current European “migrant crisis.” We also call for scholars to be public intellectuals in venues that can reframe the characterization of refugees in opposition to “fake news” fanning public fears

    Cultural and academic adjustment of refugee youth: Introduction to the special issue

    Get PDF
    © 2017 Elsevier Ltd In this introduction to the IJIR special issue on refugee youth in academic settings, the editors sought manuscripts that examined both challenges and effective practices in countries of temporary and permanent refugee resettlement. We welcomed diverse methodological approaches and empirical work at all levels and types of education (formal, non-formal, and informal). Our final selections do not fully represent the field of refugee education, as eight of the nine are studies in third countries of permanent resettlement, a designation received by only about one percent of the total refugee population. Perspectives came from the social sciences: psychology, sociology, anthropology, and sociolinguistic disciples. Themes of the articles fall into two broad categories: 1) educational challenges due to trauma, acculturation stressors, and educational issues; and 2) educational practices intended to address some of these challenges. Although the resettlement category is the smallest of the UNHCR's “durable solutions,” the authors present important findings to support refugee students’ success. These have to do with collaborative processes, issues of identity, the use of social media, and teacher training in multicultural and language support. In considering future work in this field, we conclude that dimensions of justice need to be more fully examined in other refugee solutions (such as repatriation and local integration in the first country of refuge). We recommend that more research be conducted on the current European “migrant crisis.” We also call for scholars to be public intellectuals in venues that can reframe the characterization of refugees in opposition to “fake news” fanning public fears

    Search for transient optical counterparts to high-energy IceCube neutrinos with Pan-STARRS1

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    In order to identify the sources of the observed diffuse high-energy neutrino flux, it is crucial to discover their electromagnetic counterparts. IceCube began releasing alerts for single high-energy (E>60E > 60 TeV) neutrino detections with sky localisation regions of order 1 deg radius in 2016. We used Pan-STARRS1 to follow-up five of these alerts during 2016-2017 to search for any optical transients that may be related to the neutrinos. Typically 10-20 faint (m<22.5m < 22.5 mag) extragalactic transients are found within the Pan-STARRS1 footprints and are generally consistent with being unrelated field supernovae (SNe) and AGN. We looked for unusual properties of the detected transients, such as temporal coincidence of explosion epoch with the IceCube timestamp. We found only one transient that had properties worthy of a specific follow-up. In the Pan-STARRS1 imaging for IceCube-160427A (probability to be of astrophysical origin of ∌\sim50 %), we found a SN PS16cgx, located at 10.0' from the nominal IceCube direction. Spectroscopic observations of PS16cgx showed that it was an H-poor SN at z = 0.2895. The spectra and light curve resemble some high-energy Type Ic SNe, raising the possibility of a jet driven SN with an explosion epoch temporally coincident with the neutrino detection. However, distinguishing Type Ia and Type Ic SNe at this redshift is notoriously difficult. Based on all available data we conclude that the transient is more likely to be a Type Ia with relatively weak SiII absorption and a fairly normal rest-frame r-band light curve. If, as predicted, there is no high-energy neutrino emission from Type Ia SNe, then PS16cgx must be a random coincidence, and unrelated to the IceCube-160427A. We find no other plausible optical transient for any of the five IceCube events observed down to a 5σ\sigma limiting magnitude of m∌22m \sim 22 mag, between 1 day and 25 days after detection.Comment: 20 pages, 6 figures, accepted to A&

    The influence of cycloplegic in objective refraction

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    The purpose of this study was to compare refractions measured with an autorefractor and retinoscopy in cycloplegic and non-cycloplegic eyes. The objective refractions were performed in 199 right eyes from 199 healthy young adults with a mean age of 21.6 ±2.66 years. The measurements were performed first without cycloplegia and repeated 30 minutes later with cycloplegia. Data were analyzed using Fourier decomposition of the power profile. More negative values of component M and J0 were give by non-cycloplegic autorefraction compared to cycloplegic autorefraction (p<0.001). However more positive values were given by non-cycloplegic autorefraciton regarding to the J45 vector, althought this differences were not statistically significant (p=0.233). Regarding retinoscopy, more negative values of component M where obtained with non-cycloplegic retinoscopy (p<0.001); for the cylindrical vectors J0 and J45 the retinoscopy without cycloplegic yields more negative values (p= 0.234; p= 0.112, respectively). Accepting that differences between cycloplegic and non-cycloplegic retinoscopy are only due to accommodative response, present results confirm that when performed by an experienced clinician, retinoscopy is a more reliable method to obtain objective start point for refraction under non-cycloplegic conditions

    Systemic 7-methylxanthine in retarding axial eye growth and myopia progression: a 36-month pilot study

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    The adenosine antagonist 7-methylxanthine (7-mx) works against myopia in animal models. In a clinical trial, 68 myopic children (mean age 11.3 years) received either placebo or 7-mx tablets for 12 months. All participants subsequently received 7-mx for another 12 months, after which treatment was stopped. Axial length was measured with Zeiss IOL-Master and cycloplegic refraction with Nikon Retinomax at −6, 0, 12, 24, and 36 months. Axial growth was reduced among children treated with 7-mx for 24 months compared with those only treated for the last 12 months. Myopia progression and axial eye growth slowed down in periods with 7-mx treatment, but when the treatment was stopped, both myopia progression and axial eye growth continued with invariable speed. The results indicate that 7-mx reduces eye elongation and myopia progression in childhood myopia. The treatment is safe and without side effects and may be continued until 18–20 years of age when myopia progression normally stops

    PS15cey and PS17cke: prospective candidates from the Pan-STARRS Search for kilonovae

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    Time domain astronomy was revolutionized with the discovery of the first kilonova, AT2017gfo, in August 2017, which was associated with the gravitational wave signal GW170817. Since this event, numerous wide-field surveys have been optimizing search strategies to maximize their efficiency of detecting these fast and faint transients. With the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), we have been conducting a volume-limited survey for intrinsically faint and fast-fading events to a distance of D ≃ 200 Mpc. Two promising candidates have been identified from this archival search, with sparse data - PS15cey and PS17cke. Here, we present more detailed analysis and discussion of their nature. We observe that PS15cey was a luminous, fast-declining transient at 320 Mpc. Models of BH-NS mergers with a very stiff equation of state could possibly reproduce the luminosity and decline but the physical parameters are extreme. A more likely scenario is that this was an AT2018kzr-like merger event. PS17cke was a faint and fast-declining event at 15 Mpc. We explore several explosion scenarios of this transient including models of it as a NS-NS and BH-NS merger, the outburst of a massive luminous star, and compare it against other known fast-fading transients. Although there is uncertainty in the explosion scenario due to difficulty in measuring the explosion epoch, we find PS17cke to be a plausible kilonova candidate from the model comparisons

    Impact of cholinesterase inhibitors or memantine on survival in adults with Down syndrome and dementia: clinical cohort study

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    Background: There is little evidence to guide pharmacological treatment in adults with Down syndrome and Alzheimer's disease. / Aims: To investigate the effect of cholinesterase inhibitors or memantine on survival and function in adults with Down syndrome and Alzheimer's disease. / Method: This was a naturalistic longitudinal follow-up of a clinical cohort of 310 people with Down syndrome diagnosed with Alzheimer's disease collected from specialist community services in England. / Results: Median survival time (5.59 years, 95% CI 4.67–6.67) for those on medication (n = 145, mainly cholinesterase inhibitors) was significantly greater than for those not prescribed medication (n = 165) (3.45 years, 95% CI 2.91–4.13, log-rank test P<0.001). Sequential assessments demonstrated an early effect in maintaining cognitive function. / Conclusions: Cholinesterase inhibitors appear to offer benefit for people with Down syndrome and Alzheimer's disease that is comparable with sporadic Alzheimer's disease; a trial to test the effect of earlier treatment (prodromal Alzheimer's disease) in Down syndrome may be indicated. / Declaration of interest: A.S. has undertaken consulting for Ono Pharmaceuticals, outside the submitted work. Z.W. has received a consultancy fee and grant from GE Healthcare, outside the submitted work

    GROWTH on S190814bv: Deep Synoptic Limits on the Optical/Near-Infrared Counterpart to a Neutron Star-Black Hole Merger

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    On 2019 August 14, the Advanced LIGO and Virgo interferometers detected the high-significance gravitational wave (GW) signal S190814bv. The GW data indicated that the event resulted from a neutron star--black hole (NSBH) merger, or potentially a low-mass binary black hole merger. Due to the low false alarm rate and the precise localization (23 deg2^2 at 90\%), S190814bv presented the community with the best opportunity yet to directly observe an optical/near-infrared counterpart to a NSBH merger. To search for potential counterparts, the GROWTH collaboration performed real-time image subtraction on 6 nights of public Dark Energy Camera (DECam) images acquired in the three weeks following the merger, covering >>98\% of the localization probability. Using a worldwide network of follow-up facilities, we systematically undertook spectroscopy and imaging of optical counterpart candidates. Combining these data with a photometric redshift catalog, we ruled out each candidate as the counterpart to S190814bv and we placed deep, uniform limits on the optical emission associated with S190814bv. For the nearest consistent GW distance, radiative transfer simulations of NSBH mergers constrain the ejecta mass of S190814bv to be Mej<0.04M_\mathrm{ej} < 0.04~M⊙M_{\odot} at polar viewing angles, or Mej<0.03M_\mathrm{ej} < 0.03~M⊙M_{\odot} if the opacity is Îș<2\kappa < 2~cm2^2g−1^{-1}. Assuming a tidal deformability for the neutron star at the high end of the range compatible with GW170817 results, our limits would constrain the BH spin component aligned with the orbital momentum to be χ<0.7 \chi < 0.7 for mass ratios Q<6Q < 6, with weaker constraints for more compact neutron stars. We publicly release the photometry from this campaign at http://www.astro.caltech.edu/~danny/static/s190814bv
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