Effect of desiccation on the geotechnical properties of lime-fly ash stabilized collapsible residual sand

Abstract:Berea Red Sands underlying most of the Kwazulu Natal midlands and coastal plain is a very recent unconsolidated, weakly cemented red to brown, collapsible sands. The effect of wetting and drying cycles on the Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) of compacted and cured samples of stabilized Berea Sands was investigated. Different sample mix were prepared with 4% and 8% Lime and 0%, 6% 12% and 18% Fly Ash, and tested after 4, 8 and 12 cycles of wetting and drying..

Ranking of Universities in the United Arab Emirates: Exploring a web-based technique

This study investigated university rankings in the UAE within the context of the challenges facing higher education globally in the 21st century, by using the Webometric ranking methodology. Data was collected and analysed on the top 20 UAE universities. It was apparent that the UAE universities do not perform as well as expected in the Webometrics ranking, when compared with peer countries. The ratings are slightly below that which is expected, especially when one considers measures such as research publications. Strategies to improve performance using the Webometrics indicators could have a positive impact on the UAE universities. Improvements in communicating research and their web presence is likely to move the UAE universities up the Webometrics rankings, and their academic reputation in the country

Perceived Service Quality and Customer Satisfaction – Employees’ Perspectives of Kenyan Private Universities

This paper reports on an empirical study conducted among a sample 133 employees of private higher education institution in Kenya, to examine the relationship between perceived service quality (SQ) and customer satisfaction (CS), using the HEdPERF instrument. Although service quality was measured using six dimensions namely: academic, non-academic, reputation, access, programmes and understanding, by using structural equation modelling (SEM), the six SQ dimensions needed to be collapsed into four, since these were significant to the employees of private universities. The employee is viewed as a ‘customer’ of the private higher education institution, thus service quality refers to the employee-customers’ perceptions. The results partially support the proposed conceptual model that non-academic, access, academic and reputation dimensions have a positive and significant influence on the employees’ SQ perceptions, and in turn influences their satisfaction. It can be inferred from the findings that university quality should not only be looked at in terms of academic activities alone, as non-academic aspects also need to be considered since they are deemed important to the employees. Since universities are in both national and international competition, they (management) should aim at ensuring that all services related to organizational life like physical, implicit and explicit are delivered to acceptable standards to realize increased satisfaction

The Service Quality - Customer Satisfaction Nexus: A Study of Employees and Students Perceptions in Kenyan Private Universities

The Higher Education Performance (HEdPERF) instrument was adapted to measure service quality (SQ) in private Kenyan higher education institutions (HEIs). Exploratory factor analysis was used to determine the scale’s validity, and path analysis examined the model linking the SQ and customer satisfaction (CS) constructs. It was ascertained that with respect to Kenyan private higher education, SQ is an antecedent of customer satisfaction (CS) in that it directly influences CS. Given that employees and students of selected private universities were surveyed, the results provide an opportunity for HE managers to develop strategic SQ delivery deliverables for their universities. HEdPERF was also found to be a valid measurement tool that could be used for measuring service delivery in the private higher education sector in Kenya

Evaluation of a two-question screening tool in the detection of intimate partner violence in a primary healthcare setting in South Africa

Introduction: Intimate partner violence has been recognised globally as a human rights violation. It is universally underdiagnosed and the institution of timeous multi-faceted interventions has been noted to benefit intimate partner violence victims. Currently the concept of using a screening tool to detect intimate partner violence has not been widely explored in a primary healthcare setting in South Africa, and for this reason the current study was undertaken. The objectives of this study were: (1) to determine the operating characteristics of a two-question screening tool for intimate partner violence (Women Abuse Screening Tool–short); and (2) to estimate the prevalence of intimate partner violence among women attending an outpatient department, using a validated questionnaire (Women Abuse Screening Tool).Methods: A cross-sectional study was conducted prospectively at the outpatient department of a primary care hospital, with systematic sampling of one in eight women over a period of three months. Participants were asked about their experience of intimate partner violence during the past 12 months. The Women Abuse Screening Tool–short was used to screen patients for intimate partner violence. To verify the result of the screening, women were also asked the remaining questions from the full Women Abuse Screening Tool.Results: Data were collected from 400 participants, with a response rate of 99.3%. Based on the results for the Women Abuse Screening Tool, the prevalence of intimate partner violence in the sample was 32%. The Women Abuse Screening Tool–short was shown to have a sensitivity of 45.2% and specificity of 98%.Conclusion: With its high prevalence, intimate partner violence is a health problem at this facility. The Women Abuse Screening Tool–short lacks sufficient sensitivity and therefore is not an ideal screening tool for this primary care ambulatory setting. The low sensitivity can be attributed to the participants’ understanding of the screening questions, which utilise Eurocentric definitions of intimate partner violence. Improvement in the sensitivity of the Women Abuse Screening Tool–short in this setting may be achieved by lowering the threshold for a positive result.Keywords: intimate partner violence, primary healthcare facility, screening too

Modelling microbial transport in simulated low-grade heap bioleaching systems: The hydrodynamic dispersion model

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The hydrodynamic model was developed to describe microbial growth kinetics within heap bioleaching systems. Microbial partitioning between the bulk flowing pregnant leach solution (PLS) and ore-associated phases that exist within the low-grade chalcopyrite ore bed, as a function of microbial transport between these identified phases, was investigated. Microbial transport between the bulk flowing PLS and ore-associated phases was postulated to be driven by the microbial concentration gradient between the phases, with advection and dispersion forces facilitating microbial colonisation of, and transport through, the ore bed. The population balance model (PBM) was incorporated into the hydrodynamic model to estimate mineral dissolution rates as a function of available surface area appropriately. Temporal and spatial variations in microbial concentration in the PLS and ore-associated phases are presented together with model predictions for overall ferrous and ferric iron concentrations, which account for iron concentrations in the bulk flowing PLS and that in the vicinity of the mineral surface. The model predictions for PLS and ore-associated microbial concentrations are validated with experimental data, demonstrating the improvement of this model over the previously presented ‘biomass model’. Based on Michaelis-Menten type kinetics, model-predicted true maximum specific growth rates for Acidithiobacillus ferrooxidans in the PLS and ore-associated phases were found to be 0.0004 and 0.019 h −1 , respectively. Estimated microbial attachment and detachment rates suggest that microbial growth is more prolific in the ore-associated phases with subsequent transport to the bulk flowing PLS. Sensitivity analysis of the hydrodynamic transport model to changes in the advection mass transfer coefficient, dispersion coefficient and inoculum size are discussed. For the current reactor configuration, increasing the irrigation rate from 2 to 2.5 L m −2  h −1 , i.e. increasing the advection mass transfer rate, resulted in a significant decrease in microbial retention within the ore bed.The financial assistance of the Department of Science and Technology (DST) and the National Research Foundation (NRF) of South Africa, through the South African Research Chairs Initiative (SARChI UID64778) is hereby acknowledged. Opinions expressed and conclusions arrived, are those of the author and are not necessarily to be attributed to the NRF

(S)-2-Benzyl-N-(2,6-diisopropyl­phen­yl)-1,2,3,4-tetra­hydro­isoquinoline-3-carboxamide

The asymmetric unit of the title compound, C29H34N2O, contains two mol­ecules in which the N-containing six-membered rings assume different conformations viz. half-chair and envelope. Inter­molecular N—H⋯O hydrogen bonding via the amide groups cross-link the mol­ecules in the crystal structure

(1R,3S)-N-Benzhydryl-2-benzyl-6,7-dimeth­oxy-1-phenyl-1,2,3,4-tetra­hydro­isoquinoline-3-carbothio­amide

The title compound, C38H36N2O2S, has a heterocyclic ring that assumes a half-chair conformation. The phenyl rings of neighbouring mol­ecules align forming alternating chains parallel to [100] within the crystal packing. The absolute stereochemistry of the crystal was confirmed to be R,S at the 1- and 3-positions, respectively, by proton NMR spectroscopy. A single intra­molecular N—H⋯N hydrogen bond is observed

endo-11-(Dibenzyl­amino)­tetra­cyclo­[5.4.0.03,10.05,9]undecane-8-one

The structure of the title compound, C25H27NO, is a mono-ketone penta­cyclo­undecane (PCU) mol­ecule bearing a tertiary amine group. One of the methyl­ene groups in the PCU is disordered over two orientations with site-occupancy factors of 0.621 (7) and 0.379 (7)

6,7-Dimeth­oxy-3-meth­oxy­carbonyl-1-(2-meth­oxy­phen­yl)-3,4-dihydro­isoquinoline 2-oxide

In the title compound, C20H21NO6, an N-oxide-based organocatalyst, the N-containing six-membered ring adopts a twisted half-chair conformation. No hydrogen bonding or π–π stacking was found within the crystal structure