Advancing border thinking through defamiliarisation in uncovering the darker side of coloniality and modernity in South African higher education

This article reports on a case study in which illustrations were used as prompts as a way of disrupting automatic colonised thoughts. The aim of this was to awaken deep rather than surface responses in pre-service teachers, and to introduce reflexivity as a means of introducing border thinking, which we saw as having the potential to impact positively on identity formation. Identity formation is of crucial importance for pre-service teacher education given that the system has not transformed significantly to accommodate diversification and inclusivity as a social and human rights issue. The article draws on theories designed to counteract the coloniality/modernity imaginary; it introduces border-thinking through defamiliarisation with the aim of enhancing senses of agency among pre-service teachers. Students were encouraged to draw themselves in relation to the global world. Following on from this, students participated in blogs in which they discussed their own drawings while also commenting on the drawings of others. The analysis is partially content–focussed and partially discourse-focussed. The findings reveal that the intervention prompted students to review their identities reflexively in relation to globalisation. The results show, firstly, that the intervention had positive results in terms of enhancing students’ senses of agency, and, secondly, they demonstrate, or suggest, possible ways in which the defamiliarisation process can lead to border thinking, thereby addressing coloniality

Is There Enhanced Depletion of Gas-Phase Nitrogen in Moderately Reddened Lines of Sight?

We report on the abundance of interstellar neutral nitrogen (NI) for 30 sightlines, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope (HST). NI column densities are derived by measuring the equivalent widths of several ultraviolet absorption lines and subsequently fitting those to a curve of growth. We find a mean interstellar N/H of 51+/-4 ppm. This is below the mean found by Meyer et al. of 62(+4,-3) ppm (adjusted for a difference in f-values). Our mean N/H is similar, however, to the (f-value adjusted) mean of 51+/-3 ppm found by Knauth et al. for a larger sample of sightlines with larger hydrogen column densities comparable to those in this study. We discuss the question of whether or not nitrogen shows increased gas-phase depletion in lines of sight with column densities log(H_tot) >~ 21, as claimed by Knauth et al. The nitrogen abundance in the line of sight toward HD 152236 is particularly interesting. We derive very small N/H and N/O ratios for this line of sight that may support a previous suggestion that members of the Sco OB1 association formed from an N-deficient region.Comment: Accepted in The Astrophysical Journal, 9/2006 (expected pub. date: 1/2007) 38 pages, 5 figures (4 color

The FERRUM Project: experimental and theoretical transition rates of forbidden [Sc II] lines and radiative lifetimes of metastable Sc II levels

Context. In many plasmas, long-lived metastable atomic levels are depopulated by collisions (quenched) before they decay radiatively. In low-density regions, however, the low collision rate may allow depopulation by electric dipole (E1) forbidden radiative transitions, so-called forbidden lines (mainly M1 and E2 transitions). If the atomic transition data are known, these lines are indicators of physical plasma conditions and used for abundance determination. Aims. Transition rates can be derived by combining relative intensities between the decay channels, so-called branching fractions (BFs), and the radiative lifetime of the common upper level. We use this approach for forbidden [Sc ii] lines, along with new calculations. Methods. Neither BFs for forbidden lines, nor lifetimes of metastable levels, are easily measured in a laboratory. Therefore, astrophysical BFs measured in Space Telescope Imaging Spectrograph (STIS) spectra of the strontium filament of Eta Carinae are combined with lifetime measurements using a laser probing technique on a stored ion-beam (CRYRING facility,MSL, Stockholm). These quantities are used to derive the absolute transition rates (A-values). New theoretical transition rates and lifetimes are calulated using the CIV3 code. Results. We report experimental lifetimes of the Sc ii levels 3d2 a3P0,1,2 with lifetimes 1.28, 1.42, and 1.24 s, respectively, and transition rates for lines from these levels down to 3d4s a3D in the region 8270-8390 A. These are the most important forbidden [Sc ii] transitions. New calculations for lines and metastable lifetimes are also presented, and are in good agreement with the experimental data.Comment: 5 pages. Accepted for A&

Challenging the hidden curriculum : building a lived process for responsibility in responsible management education

This essay argues that conceptualisations of responsibility in the responsible management education literature are generally superficial or unstated. We propose that this leads to practical understandings of responsibility being drawn from the hidden curriculum of socialised learning in the background of formal educational contexts. To disrupt this and enable critical thought and action, we argue for the integration of three perspectives that can be combined in a dynamic, lived process. First, we suggest that evidence-based management challenges us to seek out evidence to inform responsible management practice in ways that are thoughtful, critical and reflexive. Second, we argue that an interpretive approach employing philosophical hermeneutics connects responsibility to situated judgement about how we should interpret evidence available to us in the context of lived human experience in dialogue with others. Third, deconstruction reveals (aspects of) the ways in which the hidden curriculum constructs responsibility in the context of responsible management education texts and talk – and helps us to remain open to other possibilities. We integrate these three perspectives to arrive at a definition of responsibility as a lived process with implications for students, educators and the institutions they inhabit

The nodal dependence of long-period ocean tides in the Drake Passage

Almost three decades of bottom pressure recorder (BPR) measurements at the Drake Passage, and 31 years of hourly tide gauge data from the Vernadsky Research Base on the Antarctic Peninsula, have been used to investigate the temporal and spatial variations in this region of the three main long-period tides Mf, Mm and Mt (in order of decreasing amplitude, with periods of a fortnight, a month and one-third of a month, respectively). The amplitudes of Mf and Mt, and the phase lags for all three constituents, vary over the nodal cycle (18.61 years) in essentially the same way as in the equilibrium tide, so confirming the validity of Doodson's nodal factors for these constituents. The amplitude of Mm is found to be essentially constant, and so inconsistent at the 3σ level from the ±13% (or  ∼ ±0.15mbar) anticipated variation over the nodal cycle, which can probably be explained by energetic non-tidal variability in the records at monthly timescales and longer. The north–south differences in amplitude for all three constituents are consistent with those in a modern ocean tide model (FES2014), as are those in phase lag for Mf and Mt, while the phase difference for Mm is smaller than in the model. BPR measurements are shown to be considerably superior to coastal tide gauge data in such studies, due to the larger proportion of non-tidal variability in the latter. However, correction of the tide gauge records for non-tidal variability results in the uncertainties in nodal parameters being reduced by a factor of 2 (for Mf at least) to a magnitude comparable (approximately twice) to those obtained from the BPR data

Похибка розрахунку характеристик гармонійного сигналу

Встановлено основні джерела похибок програм визначення коефіцієнта гармонік для звичайної та подвійної точності розрахунку. Аналізуються похибки заокруглення, пов’язані із знаходженням тригонометричних функцій стандартними програмами, похибки розрахунку коефіцієнта гармонік гармонійного сигналу, на який накладено постійний складник, похибки розрахунку коефіцієнта гармонік від кількості дискретних відліків на періоді сигналу, похибки квантування по рівню, величина яких залежить від розрядності аналогово-цифрового перетворювача (АЦП). Шляхом моделювання визначено величину порогу чутливості по коефіцієнту гармонік.The basic sources of the errors of software for calculation of the harmonic factor for an ordinary and double accuracy of calculation are established. Errors in rounding, related to the calculation of trigonometric functions by standard programs, errors of calculation of the harmonic factor of a harmonic signal with an imposed permanent constituent, errors of calculation of the harmonic factor from the number of discrete counts on the signal period, errors of quantum by level the value which depends from the value ADC bits are analyzed. The threshold value of sensitivity by a harmonic factor was evaluated by modelling.Рассмотрены основные источники погрешностей программ расчета коэффициента гармоник с обычной и двойной точностью вычислений. Анализируются погрешности округления, связанные с вычислением тригонометрических функций стандартными программами, погрешности расчета коэффициента гармоник гармонического сигнала с постоянной составляющей, погрешности расчета коэффициента гармоник от количества дискретных отсчетов на периоде гармонического сигнала, погрешности квантования по уровню, величина которых зависит от разрядности аналого-цифрового преобразователя (АЦП). Путем моделирования определена величина порога чувствительности по коэффициенту гармоник