Validation of the high performance leadership competencies as measured by an assessment centre in-basket

The original publication is available at http://www.sajip.co.zaCITATION: Spangenberg, H. H. & Theron, C. C. 2003. Validation of the high performance leadership competencies as measured by an assessment centre in-basket. SA Journal of Industrial Psychology, 29(2):29-38, doi:10.4102/sajip.v29i2.106.The purpose of this study was to validate Schroder’s High Performance Leadership Competencies (HPLCs), measured by a specially designed In-basket, against multiple criteria. These consisted of six measures of managerial success, representing managerial advancement and salary progress criteria, and a newly developed comprehensive measure of work unit performance, the Performance Index. An environmental dynamism and complexity questionnaire served as moderator variable. Results indicated disappointing predictive validity quotients for the HPLCs as measured by an In-basket, in contrast to satisfactory predictive and construct validity obtained in previous studies by means of a full assessment centre. The implications of the findings are discussed and suggestions are made for improving the validity of the In-basket.Die doel van hierdie studie was die validering van Schroder se Hoëvlak Leierskapsbevoegdhede, gemeet deur ‘n spesiaal ontwerpte Posmandjie, teen veelvoudige kriteria. Dit behels ses metings van bestuursukses wat bestuursbevorderings- en salarisvorderingskriteria insluit, sowel as ‘n nuutontwikkelde, omvattende meting van werkeenheidsprestasie, die Prestasie indeks. ‘n Vraelys wat die dinamika en kompleksiteit van die omgewing meet, het as moderator veranderlike gedien. Resultate dui op teleurstellende geldigheidskwosiënte vir die Hoëvlak Leierskapsbevoegdhede soos gemeet deur ‘n posmandjie, in teenstelling met bevredigende voorspellings- en konstrukgeldigheid wat in vorige studies deur middel van ‘n volle takseersentrum verkry is. Die bevindinge word bespreek en voorstelle word gemaak om die geldigheidskwosiënte te verbeter.https://sajip.co.za/index.php/sajip/article/view/106Publisher's versio

Bosonization in d=2 from finite chiral determinants with a Gauss decomposition

We show how to bosonize two-dimensional non-abelian models using finite chiral determinants calculated from a Gauss decomposition. The calculation is quite straightforward and hardly more involved than for the abelian case. In particular, the counterterm $A\bar A$, which is normally motivated from gauge invariance and then added by hand, appears naturally in this approach.Comment: 4 pages, Revte

Transcription-associated breaks in Xeroderma Pigmentosum group D cells from patients with combined features of Xeroderma Pigmentosum and Cockayne Syndrome

Defects in the XPD gene can result in several clinical phenotypes, including xeroderma pigmentosum (XP), trichothiodystrophy, and, less frequently, the combined phenotype of XP and Cockayne syndrome (XP-D/CS). We previously showed that in cells from two XP-D/CS patients, breaks were introduced into cellular DNA on exposure to UV damage, but these breaks were not at the sites of the damage. In the present work, we show that three further XP-D/CS patients show the same peculiar breakage phenomenon. We show that these breaks can be visualized inside the cells by immunofluorescence using antibodies to either gamma-H2AX or poly-ADP-ribose and that they can be generated by the introduction of plasmids harboring methylation or oxidative damage as well as by UV photoproducts. Inhibition of RNA polymerase II transcription by four different inhibitors dramatically reduced the number of UV-induced breaks. Furthermore, the breaks were dependent on the nucleotide excision repair (NER) machinery. These data are consistent with our hypothesis that the NER machinery introduces the breaks at sites of transcription initiation. During transcription in UV-irradiated XP-D/CS cells, phosphorylation of the carboxy-terminal domain of RNA polymerase II occurred normally, but the elongating form of the polymerase remained blocked at lesions and was eventually degraded

Comparison of Quantitative Techniques including Xpert MTB/RIF to Evaluate Mycobacterial Burden

Introduction: Accurate quantification of mycobacterial load is important for the evaluation of patient infectiousness, disease severity and monitoring treatment response in human and in-vitro laboratory models of disease. We hypothesized that newer techniques would perform as well as solid media culture to quantify mycobacterial burden in laboratory specimens. Methods: We compared the turn-around-time, detection-threshold, dynamic range, reproducibility, relative discriminative ability, of 4 mycobacterial load determination techniques: automated liquid culture (BACTEC-MGIT-960), [3H]-uracil incorporation assays, luciferase-reporter construct bioluminescence, and quantitative PCR(Xpert -MTB/RIF) using serial dilutions of Mycobacterium bovis and Mycobacterium tuberculosis H37RV. Mycobacterial colony-forming-units(CFU) using 7H10-Middlebrook solid media served as the reference standard. Results: All 4 assays correlated well with the reference standard, however, bioluminescence and uracil assays had a detection threshold ≥1×103 organisms. By contrast, BACTEC-MGIT-960 liquid culture, although only providing results in days, was user-friendly, had the lowest detection threshold (<10 organisms), the greatest discriminative ability (1 vs. 10 organisms; p = 0.02), and the best reproducibility (coefficient of variance of 2% vs. 38% compared to uracil incorporation; p = 0.02). Xpert-MTB/RIF correlated well with mycobacterial load, had a rapid turn-around-time (<2 hours), was user friendly, but had a detection limit of ~100 organisms. Conclusions: Choosing a technique to quantify mycobacterial burden for laboratory or clinical research depends on availability of resources and the question being addressed. Automated liquid culture has good discriminative ability and low detection threshold but results are only obtained in days. Xpert MTB/RIF provides rapid quantification of mycobacterial burden, but has a poorer discrimination and detection threshold

Dynamic Impedance of Two-Dimensional Superconducting Films Near the Superconducting Transition

The sheet impedances, Z(w,T), of several superconducting a-Mo77Ge23 films and one In/InOx film have been measured in zero field using a two-coil mutual inductance technique at frequencies from 100 Hz to 100 kHz. Z(w,T) is found to have three contributions: the inductive superfluid, renormalized by nonvortex phase fluctuations; conventional vortex-antivortex pairs, whose contribution turns on very rapidly just below the usual Kosterlitz-Thouless-Berezinskii unbinding temperature; and an anomalous contribution. The latter is predominantly resistive, persists well below the KTB temperature, and is weakly dependent on frequency down to remarkably low frequencies, at least 100 Hz. It increases with T as e-U'(T)/kT, where the activation energy, U'(T), is about half the energy to create a vortex-antivortex pair, indicating that the frequency dependence is that of individual excitations, rather than critical behavior.Comment: 10 pages, 10 figs; subm PR

Mitigation and Adaptation Practices to the Impact of Climate Change on Wine Grape Production, with Special Reference to the South African Context

In South Africa, environmentally and socio-economically sustainable wine grape production is promotedby governmental and private initiatives. All the initiatives contribute to establishing a scientificallybased response strategy of agro-systems to ensure sustainable production under future expected climateconditions. South African wine grape producers would probably have to cultivate their grapevines underhigher atmospheric CO2 levels and in warmer, mostly drier, conditions. Due to the projected increase inclimatic variability, an effort must be made to improve the resilience of vines against these environmentalconditions. Whole-vine functioning and balances should be considered when adjustments are madeto current long and short term cultivation practices. All practices should be aimed at promoting thedevelopment of a deep, dense and buffered root system that is able to support a well-developed canopywith optimal microclimate that would sustain a high yield of good quality. Mitigation and adaptationstrategies would most likely have to be region specific, and small scale terroir data, (which should includeboth climate and terrain/soil information) may play a critical role in decision-making

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

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