76 research outputs found

    Students’ emerging pedagogical reflexivities in respect of their "student teacherly becoming" on a PGCE Diversity and Inclusivity module

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    Situated in the context of teaching in higher education, the article provides a discussion on how student teachers in a Post Graduate Certificate of Education (PGCE) module mediate their ‘teacherly becoming’ (Author 2012) as pre-service teachers. The article presents the argument that learning to become a professional teacher involves not only what the students are learning, but also who they are becoming. The data for the article is drawn from student assignments which invited students to draw on the module readings and class discussions to consider their positioning as intentional/unintentional bearers of the past. The assignment required of them to consider how their emerging reflexivities as student teachers are influenced by their personal and educational backgrounds, and how these affected their ‘becoming’ as student teachers in the PGCE programme. The data is presented and discussed on the basis of four themes that emerged from the student essays. The article concludes by suggesting that modules that prepare student teachers for the complexity of the teaching profession and interaction with their students will be more productive if opportunities are provided in the module’s assessment modalities, for the students to reflexively engage with aspects of their ‘being and becoming’ as pre-service teachers

    Trabecular bone density in premenopausal rheumatoid arthritis patients

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    Objective. This study was undertaken to compare trabecular bone mineral density (BMD) in premenopausal rheumatoid arthritis. (RA) patients and normal age-matched controls.Method. A protocol was designed to record age, duration of disease, use of corticosteroids (CS) and/ or slow-acting antirheumatic drug (SAARD) therapy together with duration of such therapy. BMD was measured using the Hologic QDR 1 000 dual energy X-ray absorptiometer. The first four lumbar vertebrae and the left femur were measured in 56 RA patients and 165 controls. Height and weight were measured. Comparisons were made between RA patients and controls, as well as between subgroups of RA patients based on CS therapy.Results. Patients with RA had significantly lower BMD (P < 0.05) at all the sites than the normal controls. The mean duration of RA at the time of study was 60 months (standard deviation 58 months). Thirteen RA patients had used CS in doses less than 10 mg daily for 6 months or longer (mean 19 months), while 25 patients had been on SAARD for an excess of 6 months (mean 23 months). The CS-treated patients had significantly lower BMD than untreated subjects at the femoral neck and inter-trochanteric region (P < 0.05), but not at the lumbar spine. However, when compared with normal controls, the CS-treated subgroups had significantly lower BMD at the lumbar spine and all femoral areas. Trochanteric BMD was the best determinant of the RA group, with a sensitivity of 65% and specificity of 77%. The positive predictive value was 16%, while the negative predictive value was 10%. Using Bayes' theorem, the prevalence of osteopenia in RA was found to be6%.Conclusion. We conclude that generalised bone loss is a systemic feature of RA and that loss at the spine and femur may be aggravated by CS therapy

    Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

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    New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

    The 1.28 GHz MeerKAT DEEP2 Image

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    We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one qb » ¢ 68 FWHM primarybeam area with θ = 7 6 FWHM resolution and s = m - n 0.55 0.01 Jy beam 1 rms noise. Its J2000 center position α = 04h 13m 26 4, δ = −80° 00′ 00″ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary-beam attenuation pattern, estimate telescope pointing errors, and pinpoint (u, v) coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differential source count by combining a power-law count fit to the DEEP2 confusion P(D) distribution from 0.25 to 10 μJy with counts of individual DEEP2 sources between 10 μJy and 2.5 mJy. Most sources fainter than S ∼ 100 μJy are distant star-forming galaxies (SFGs) obeying the far-IR/ radio correlation, and sources stronger than 0.25 μJy account for ∼93% of the radio background produced by SFGs. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson model for the evolution of SFGs based on UV and infrared data underpredicts our 1.4 GHz source count in the range -5 log Jy 4 [ ( )] S

    Revival of the Magnetar PSR J1622-4950: Observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

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    New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100 larger than during its dormant state. The X-ray flux one month after reactivation was at least 800 larger than during quiescence, and has been decaying exponentially on a 111 19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation
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