From foreigners to citizens : conceptualising students' entry into disciplinary communities of practice

CITATION: Young, G. & Kotze, A. 2009. From foreigners to citizens : conceptualising students' entry into disciplinary communities of practice. Akroterion, 54:125-139, doi:10.7445/54-0-31.The original publication is available at http://akroterion.journals.ac.zaThe discipline of Classics, like most other disciplines in Higher Education contexts, faces numerous challenges related to changed national and international expectations. This article argues that in order to meet these challenges the discipline needs to reflect on its activities and teaching practices in a structured and deliberate way. Such reflection can be facilitated by theoretical frameworks designed in education research. We present one such framework, the “Communities of practice” as designed by Wenger (1998) and show how the framework can be employed, at a theoretical level, to conceptualise the challenges facing the discipline as well as to enhance teaching practices in an undergraduate Greek class, through an institutionally supported project. By applying this framework educators can assist students both in preparing for their careers as well as in engaging with their studies.http://akroterion.journals.ac.za/pub/article/view/31Publisher's versio

Investigating Long-Term Behaviour of X-ray Binaries Using Archival Data

Long term modulations have been detected in a wide variety of both low and high-mass X-ray binaries. The All Sky Monitor on board the Rossi X-ray Timing Explorer provides the most extensive (~15 years) and sensitive X-ray archive for studying such behaviour. Since those variations were often intermittent and/or aperiodic, we used a time-dependent Dynamic Power Spectrum method to examine how the modulations themselves vary with time in a systematic way. Some were found to be remarkably stable, while others show a range of properties, from even longer variability time-scales to quite chaotic behaviour

On the spin modulated circular polarization from the intermediate polars NY Lup and IGRJ1509-6649

We report on high time resolution, high signal/noise, photo-polarimetry of the intermediate polars NY Lup and IGRJ1509-6649. Our observations confirm the detection and colour dependence of circular polarization from NY Lup and additionally show a clear white dwarf, spin modulated signal. From our new high signal/noise photometry we have unambiguously detected wavelength dependent spin and beat periods and harmonics thereof. IGRJ1509-6649 is discovered to also have a particularly strong spin modulated circularly polarized signal. It appears double peaked through the I filter and single peaked through the B filter, consistent with cyclotron emission from a white dwarf with a relatively strong magnetic field. We discuss the implied accretion geometries in these two systems and any bearing this may have on the possible relationship with the connection between polars and soft X-ray-emitting IPs. The relatively strong magnetic fields is also suggestive of them being polar progenitors.Comment: 8 pages, 6 figures and 1 table. Accepted for publication in MNRA

Dog Urine Has Acute Impacts on Soil Chemistry in Urban Greenspaces

Urban residents and their pets utilize urban greenspaces daily. As urban dog ownership rates increase globally, urban greenspaces are under mounting pressure even as the benefits and services they provide become more important. The urine of dogs is high in nitrogen (N) and may represent a significant portion of the annual urban N load. We examined the spatial distribution and impact of N deposition from dog urine on soils in three urban greenspace typologies in Finland: Parks, Tree Alleys, and Remnant Forests. We analyzed soil from around trees, lampposts and lawn areas near walking paths, and compared these to soils from lawn areas 8 m away from pathways. Soil nitrate, ammonium, total N concentrations, and electrical conductivity were significantly higher and soil pH significantly lower near path-side trees and poles relative to the 8 m lawn plots. Also, stable isotope analysis indicates that the primary source of path-side N are distinct from those of the 8 m lawn plots, supporting our hypothesis that dogs are a significant source of N in urban greenspaces, but that this deposition occurs in a restricted zone associated with walking paths. Additionally, we found that Remnant Forests were the least impacted of the three typologies analyzed. We recommend that landscape planners acknowledge this impact, and design parks to reduce or isolate this source of N from the wider environment.Peer reviewe

Exploring inside-out Doppler tomography: magnetic cataclysmic variables

Context. Doppler tomography of magnetic cataclysmic variables is a valuable tool for the interpretation of the complex spectroscopic emission line profiles observed for these systems

Genetic relationships between three indigenous cattle breeds in Mozambique

This study provides the first account of genetic relationships between three indigenous cattle breeds from Mozambique. Forty-two blood group factors and six blood proteins revealed genetic variation of 84% (Angone), 88% (Bovine de Tete) and 90% (Landim) at the loci studied. Average heterozygosity values ranged from 33% for Angone and Bovine de Tete to 35% for the Landim. The genetic distance was greatest between the Landim and both the Bovine de Tete and the Angone breeds, whereas the smallest genetic distance was observed between the Bovine de Tete and the Angone. These results show the intermediate relationship of Bovine de Tete with the Angone and Landim breeds and show that the Bovine de Tete is an admixture of taurine and indicus genes. (South African Journal of Animal Science, 2000, 30(2): 92-97

The Effect of Egg Embryonation on Field-Use of a Hookworm Benzimidazole-Sensitivity Egg Hatch Assay in Yunnan Province, People's Republic of China

With the implementation of mass drug administration programmes for the control of human soil transmitted helminths there is a need to develop drug sensitivity monitoring tools to detect the emergence of resistance. The present study aimed to use an egg hatch assay to measure benzimidazole sensitivity in human hookworms in a field setting in Yunnan province, People's Republic of China, in order to assess whether the assay offered a practical means of monitoring drug sensitivity in human hookworms in such a location. The assay proved able to generate dose response data, which allowed for the drug sensitivity of the hookworms in the local children to be described; the mean IC50 was 0.10 ug/ml thiabendazole. The study also found that practical issues associated with stool collection procedures, specifically the embryonation of some eggs during the time elapsing between stool deposition and egg recovery, can have an impact on the drug sensitivity data. We suggest means for data analysis that overcome the impact of egg embryonation on drug dose response data, which should allow for the use of such assays at different field sites worldwide