University of Johannesburg

About: University of Johannesburg is a education organization based out in Johannesburg, South Africa. It is known for research contribution in the topics: Population & Tourism. The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.

The validation of the turnover intention scale

Abstract: Orientation: Turnover intention as a construct has attracted increased research attention in the recent past, but there are seemingly not many valid and reliable scales around to measure turnover intention. Research purpose: This study focused on the validation of a shortened, six-item version of the turnover intention scale (TIS-6). Motivation for the study: The research question of whether the TIS-6 is a reliable and a valid scale for measuring turnover intention and for predicting actual turnover was addressed in this study. Research design, approach and method: The study was based on a census-based sample ( n = 2429) of employees in an information, communication and technology (ICT) sector company ( N = 23 134) where the TIS-6 was used as one of the criterion variables. The leavers (those who left the company) in this sample were compared with the stayers (those who remained in the employ of the company) in this sample in respect of different variables used in the study. Main findings: It was established that the TIS-6 could measure turnover intentions reliably (α= 0.80). The TIS-6 could significantly distinguish between leavers and stayers (actual turnover), thereby confirming its criterion-predictive validity. The scale also established statistically significant differences between leavers and stayers in respect of a number of the remaining theoretical variables used in the study, thereby also confirming its differential validity. These comparisons were conducted for both the 4-month and the 4-year period after the survey was conducted. Practical/managerial implications: Turnover intention is related to a number of variables in the study which necessitates a reappraisal and a reconceptualisation of existing turnover intention models. Contribution/value-add: The TIS-6 can be used as a reliable and valid scale to assess turnover intentions and can therefore be used in research to validly and reliably assess turnover intentions or to predict actual turnover.

Luminosity determination in pp collisions at √s = 8 TeV using the ATLAS detector at the LHC

Abstract: The luminosity determination for the ATLAS detector at the LHC during pp collisions at s√= 8 TeV in 2012 is presented. The evaluation of the luminosity scale is performed using several luminometers ...

The Chemistry of Plant-Microbe Interactions in the Rhizosphere and the Potential for Metabolomics to Reveal Signaling Related to Defense Priming and Induced Systemic Resistance.

Abstract: Plant roots communicate with microbes in a sophisticated manner through chemical communication within the rhizosphere, thereby leading to biofilm formation of beneficial microbes and, in the case of plant growth-promoting rhizomicrobes / -bacteria (PGPR), resulting in priming of defense or induced resistance in the plant host. The knowledge of plant-plant and plant-microbe interactions have been greatly extended over recent years; however, the chemical communication leading to priming is far from being well understood. Furthermore, linkage between below- and above-ground plant physiological processes adds to the complexity. In metabolomics studies, the main aim is to profile and annotate all exo- and endo-metabolites in a biological system that drive and participate in physiological processes. Recent advances in this field has enabled researchers to analyze hundreds of compounds in one sample over a short time period. Here, from a metabolomics viewpoint, we review the interactions within the rhizosphere and subsequent above-ground ‘signalomics’, and emphasize the contributions that mass spectrometric-based metabolomic approaches can bring to the study of plant-beneficial – and priming events.

Are carbon nanotube effects on green algae caused by shading and agglomeration

Abstract: Due to growing production, carbon nanotubes (CNT) may soon be found in a broad range of products and thus in the environment. In this work, an algal growth test was developed to determine effects of pristine and oxidized CNT on the green algae Chlorella vulgaris and Pseudokirchneriella subcapitata. CNT suspensions were prepared in algal test medium and characterized taking into account the suspension age, the reduced light transmittance of nanoparticle suspensions defined as shading of CNT and quantified by UV/vis spectroscopy, and the agglomeration of the CNT and of the algal cells. Growth inhibition and photosynthetic activity were investigated as end points. Growth of C. vulgaris was inhibited with effect concentrations of 50% (EC50) values of 1.8 mg CNT/L and of 24 mg CNT/L in well dispersed and in agglomerated suspensions, respectively, and 20 mg CNT/L and 36 mg CNT/L for P. subcapitata, respectively. However, the photosynthetic activity was not affected. Growth inhibition was highly correlated with ...