University of South Africa

About: University of South Africa is a education organization based out in Pretoria, South Africa. It is known for research contribution in the topics: Context (language use) & Population. The organization has 8478 authors who have published 19960 publications receiving 237688 citations. The organization is also known as: Unisa.

A high energy density asymmetric supercapacitor utilizing a nickel phosphate/graphene foam composite as the cathode and carbonized iron cations adsorbed onto polyaniline as the anode

Abstract: The South African Research Chairs Initiative (SARChI) of the Department of Science and Technology and the National Research Foundation (NRF) of South Africa (Grant No. 61056).

How efficient are referral hospitals in Uganda? A data envelopment analysis and tobit regression approach

Abstract: Hospitals represent a significant proportion of health expenditures in Uganda, accounting for about 26 % of total health expenditure. Improving the technical efficiency of hospitals in Uganda can result in large savings which can be devoted to expand access to services and improve quality of care. This paper explores the technical efficiency of referral hospitals in Uganda during the 2012/2013 financial year. This was a cross sectional study using secondary data. Input and output data were obtained from the Uganda Ministry of Health annual health sector performance report for the period July 1, 2012 to June 30, 2013 for the 14 public sector regional referral and 4 large private not for profit hospitals. We assumed an output-oriented model with Variable Returns to Scale to estimate the efficiency score for each hospital using Data Envelopment Analysis (DEA) with STATA13. Using a Tobit model DEA, efficiency scores were regressed against selected institutional and contextual/environmental factors to estimate their impacts on efficiency. The average variable returns to scale (Pure) technical efficiency score was 91.4 % and the average scale efficiency score was 87.1 % while the average constant returns to scale technical efficiency score was 79.4 %. Technically inefficient hospitals could have become more efficient by increasing the outpatient department visits by 45,943; and inpatient days by 31,425 without changing the total number of inputs. Alternatively, they would achieve efficiency by for example transferring the excess 216 medical staff and 454 beds to other levels of the health system without changing the total number of outputs. Tobit regression indicates that significant factors in explaining hospital efficiency are: hospital size (p < 0.01); bed occupancy rate (p < 0.01) and outpatient visits as a proportion of inpatient days (p < 0.05). Hospitals identified at the high and low extremes of efficiency should be investigated further to determine how and why production processes are operating differently at these hospitals. As policy makers gain insight into mechanisms promoting hospital services utilization in hospitals with high efficiency they can develop context-appropriate strategies for supporting hospitals with low efficiency to improve their service and thereby better address unmet needs for hospital services in Uganda.

Synthesis and nutrient release patterns of a biochar-based N–P–K slow-release fertilizer

Abstract: Biochar has excellent solute adsorption capacity, yet few studies have investigated its application as a nutrient carrier in the development of slow-release fertilizers. The current study developed a biochar-based N–P–K fertilizer (BSRF) and evaluated its nutrient release patterns relative to a conventional fertilizer. SEM and EDX analyses confirmed the coarse and highly porous microstructure of the biochar (SBC) that enabled it to effectively sorb NO3 −, PO4 3−, and K+ and form a nutrient-impregnated BSRF. BSRF had lower NO3 −, PO4 3−, and K+ release than the conventional chemical fertilizer, demonstrating its low release behavior. BSRF-amended sandy soil had higher water retention capacity than that amended with a conventional chemical fertilizer. BSRF has potential to reduce nutrient leaching, improve water retention, and hence increase crop nutrient and water use efficiencies. Future research should focus on understanding nutrient release mechanisms, synchronization of nutrient release with plant uptake, and applications of the BSRF in environmental remediation.