26 research outputs found
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A system dynamics modelling approach to restoration of natural capital: An economic assessment of costs and benefits of different land use options and value added products to assist in the control of invasive alien plants in the fynbos biome of the Western Cape Province, South Africa.
Invasive alien plants (IAPs) are major the major causes of environmental degradation in the Western Cape Province, South Africa. IAPs clearing activities have been implemented and funded largely by the state through the Working for Water Programme under the auspices of the Department of Environmental Affairs� Natural Resource Management directorates (DEA: NRM), to counteract these negative impacts. Using a system dynamics modelling approach, this study estimates the costs and benefits of clearing IAPs, using the cleared biomass to make VAPs and restoring the cleared land to various agricultural land use options under five broad management scenarios using a system dynamics modelling approach. The simulation results show positive cumulative net present values (NPV) when a private sector co-finance of between 20% and 100% from the private sector is included to clear IAPs whilst at the same time restoring the cleared land to productive agricultural land uses and making VAPs from the cleared IAPs biomass. However if the clearing of IAPs is conducted by the state alone (with no private sector co-finance) from 2008 whilst omitting the restoration of cleared land to productive agricultural land use options and the use of IAPs biomass to make VAPs , the cumulative NPV is negative.
Keywords: land use, restoration, natural capital, invasive alien plants, opportunity cost, value added products, system dynamics modelling, cost benefit analysi
A system dynamics modelling approach to restoration of natural capital: An economic assessment of costs and benefits of different land use options and value added products to assist in the control of invasive alien plants in the fynbos biome of the Western Cape Province, South Africa.
Invasive alien plants (IAPs) are major the major causes of environmental degradation in the Western Cape Province, South Africa. IAPs clearing activities have been implemented and funded largely by the state through the Working for Water Programme under the auspices of the Department of Environmental Affairs� Natural Resource Management directorates (DEA: NRM), to counteract these negative impacts. Using a system dynamics modelling approach, this study estimates the costs and benefits of clearing IAPs, using the cleared biomass to make VAPs and restoring the cleared land to various agricultural land use options under five broad management scenarios using a system dynamics modelling approach. The simulation results show positive cumulative net present values (NPV) when a private sector co-finance of between 20% and 100% from the private sector is included to clear IAPs whilst at the same time restoring the cleared land to productive agricultural land uses and making VAPs from the cleared IAPs biomass. However if the clearing of IAPs is conducted by the state alone (with no private sector co-finance) from 2008 whilst omitting the restoration of cleared land to productive agricultural land use options and the use of IAPs biomass to make VAPs , the cumulative NPV is negative.
Keywords: land use, restoration, natural capital, invasive alien plants, opportunity cost, value added products, system dynamics modelling, cost benefit analysi
The effect of accessibility and value addition on the costs of controlling invasive alien plants in South Africa: A three-species system dynamics model in the fynbos and grassland biomes
The impact of community- versus clinic-based adherence clubs on loss from care and viral suppression for antiretroviral therapy patients: Findings from a pragmatic randomized controlled trial in South Africa
BACKGROUND:Adherence clubs, where groups of 25-30 patients who are virally suppressed on antiretroviral therapy (ART) meet for counseling and medication pickup, represent an innovative model to retain patients in care and facilitate task-shifting. This intervention replaces traditional clinical care encounters with a 1-hour group session every 2-3 months, and can be organized at a clinic or a community venue. We performed a pragmatic randomized controlled trial to compare loss from club-based care between community- and clinic-based adherence clubs. METHODS AND FINDINGS:Patients on ART with undetectable viral load at Witkoppen Health and Welfare Centre in Johannesburg, South Africa, were randomized 1:1 to a clinic- or community-based adherence club. Clubs were held every other month. All participants received annual viral load monitoring and medical exam at the clinic. Participants were referred back to clinic-based standard care if they missed a club visit and did not pick up ART medications within 5 days, had 2 consecutive late ART medication pickups, developed a disqualifying (excluding) comorbidity, or had viral rebound. From February 12, 2014, to May 31, 2015, we randomized 775 eligible adults into 12 pairs of clubs-376 (49%) into clinic-based clubs and 399 (51%) into community-based clubs. Characteristics were similar by arm: 65% female, median age 38 years, and median CD4 count 506 cells/mm3. Overall, 47% (95% CI 44%-51%) experienced the primary outcome of loss from club-based care. Among community-based club participants, the cumulative proportion lost from club-based care was 52% (95% CI 47%-57%), compared to 43% (95% CI 38%-48%, p = 0.002) among clinic-based club participants. The risk of loss to club-based care was higher among participants assigned to community-based clubs than among those assigned to clinic-based clubs (adjusted hazard ratio 1.38, 95% CI 1.02-1.87, p = 0.032), after accounting for sex, age, nationality, time on ART, baseline CD4 count, and employment status. Among those who were lost from club-based care (n = 367), the most common reason was missing a club visit and the associated ART medication pickup entirely (54%, 95% CI 49%-59%), and was similar by arm (p = 0.086). Development of an excluding comorbidity occurred in 3% overall of those lost from club-based care, and was not different by arm (p = 0.816); no deaths occurred in either arm during club-based care. Viral rebound occurred in 13% of those lost from community club-based care and 21% of those lost from clinic-based care (p = 0.051). In post hoc secondary analysis, among those referred to standard care, 72% (95% CI 68%-77%) reengaged in clinic-based care within 90 days of their club-based care discontinuation date. The main limitations of the trial are the lack of a comparison group receiving routine clinic-based standard care and the potential limited generalizability due to the single-clinic setting. CONCLUSIONS:These findings demonstrate that overall loss from an adherence club intervention was high in this setting and that, importantly, it was worse in community-based adherence clubs compared to those based at the clinic. We urge caution in assuming that the effectiveness of clinic-based interventions will carry over to community settings, without a better understanding of patient-level factors associated with successful retention in care. TRIAL REGISTRATION:Pan African Clinical Trials Registry (PACTR201602001460157)
Perceptions of community and clinic-based adherence clubs for patients stable on antiretroviral treatment : a mixed methods study
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South African National Survey of Research and Experimental Development: Statistical report 2013/14
Commissioned by the Department of Science and Technology, MarchThe 2013/14 R&D survey shows that gross expenditure on research and development (GERD) has increased in nominal terms in South Africa for the third consecutive year after the contraction in the 2009/10 and 2010/11 survey years. This is an indication that the R&D expenditure trend has stabilised. These trends reflect the general pattern of domestic economic growth and track the global trend in R&D expenditure. While the results show an improving outlook for R&D investment in the country, the magnitude of annual real increases in GERD
still appear inadequate. Increases did not keep pace with the real GDP growth over the four years 2010 to 2013, this is why R&D intensity has remained constant at 0.73%. From a policy view, R&D should expand at a faster rate than economic growth if South Africa is to significantly improve its competitiveness
Chinese engagement of Zimbabwe and the limits of elite agency:
This article contends that Zimbabwe’s agency in its engagement with China has been limited and at best circumscribed. This owes to factors such as indifference by state authorities to cooperation with civil society actors in negotiating with Chinese actors, the desperation of the The Zimbabwe African National Union – Patriotic Front regime in the face of isolation by erstwhile partners as well as the opacity and secrecy that characterizes significant areas of the Zimbabwe–China relationship. The pressing need for critical institutions such as parliament to play independent oversight roles as well as the creation of space for civil society watchdog functions are highlighted as key enablers if Zimbabwean agency is to generate positive gains from the country’s engagement with China
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South African National Survey of Research and Experimental Development: stastistical report 2011/12
Commisioned by the Department of Science and Technology, MarchThis report presents selected data tables of the 2011/12 South African National Survey of Research and Experimental Development (R&D survey). The tables in this report cover the main dimensions of R&D statistics in terms of expenditure and human resources