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Critically endangered Hooded Vultures (Necrosyrtes monachus Temminck, 1823), like many vulture species globally, are experiencing rapid population declines due to anthropogenic factors such as poisonings, human persecution, trading for belief-based use, and habitat loss/degradation. The Hooded Vulture is widespread across sub-Saharan Africa. Although it is considered one of the most abundant vultures in West Africa, this vulture species is less common in East and southern Africa, with the population at the southern-most edge of the distribution (in South Africa and Eswatini) estimated at only 100–200 mature individuals. The distribution of Hooded Vultures has contracted dramatically in southern Africa, with breeding populations largely confined to protected areas such as the Greater Kruger National Park. This study aimed to investigate the genetic diversity of the southern African range-edge population and assess if the recent contraction in the distribution has resulted in the population experiencing a genetic bottleneck. Sixteen microsatellite loci were amplified for samples collected along the Olifants River in the Greater Kruger National Park (n = 30). The genetic diversity in the South African population was compared to samples (n = 30) collected in Ghana, where Hooded Vultures are more abundant. Contrary to expectations, the South African peripheral Hooded Vulture population showed higher levels of heterozygosity (HO = 0.495) than the Ghanaian population (HO = 0.315). Neither population showed signs of recent bottleneck events when tested using demographic modelling and Approximate Bayesian computation (ABC). However, both populations showed high levels of inbreeding and relatedness. Our results suggest that despite being a small peripheral population, the South African Hooded Vulture population showed a similar level of genetic diversity as individuals sampled from a core population within the species distribution (in Ghana). This study supports the need for Hooded Vulture conservation efforts in the southern African region and highlights the evolutionary importance of range-edge populations. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the application of biostimulation and bioventing for the treatment of crude oil-contaminated soils. The research needed to check how various industrial biostimulants will perform in the treatment of contaminated soils and whether or not there is a synergetic effect that has to do with the stimulant composition. Soil samples used for this study were collected from South Africa. The soil samples were air-dried for 24 h and subsequently passed through a standard sieve of 2 mm screen. The soil consists of 79.32% sand (2.00-0.02 mm), 14.71% silt (0.02-0.002 mm) and 5.97% clay (< 0.002 mm). A microcosm system containing 1 kg of soil contaminated with crude oil (5% w/w) for biostimulation (BSTc) treatment was amended with varying ratios of municipal wastewater (MWW) and brewery wastewater (BWW) to investigate the possible synergy. The bioventing (BVTc) treatment involves the supply of atmospheric air to the bioreactors through the vadose zone for 30mins flow duration every 48 h intervals at ambient condition for 28 days. The BSTc and BVTc treatments recorded 48-58% and 54-75% total petroleum hydrocarbon (TPH) removal efficiencies, respectively, as the BWW amendment noted appreciable removal compared to MWW, while the control treatment recorded 35%. The result showed that the attempt to boost the TPH removal efficiency using the bioventing with the wastewater amendment was effective, as the presence of enough oxygen in the system resuscitated the activities of the microbial community for enhanced TPH biodegradation. This study inferred that combined bioventing and biostimulation techniques proved to be an effective bioremediation strategy for the treatment of crude oil contaminated soils and could serve as a vital tool towards the mitigation of pollution aftermath faced by communities involved in oil production and/or processing activities. [ABSTRACT FROM AUTHOR]

The present study investigates the ecology and distribution of ostracod species and assemblages from 62 inland waterbodies in the Eastern Cape province of South Africa and tests the influence of two major climatic zones (Arid steppe climate BS and Warm temperate humid climate Cf) and two primary catchments (Kowie and Great Fish Rivers), as well as broad gradients of altitude and several local environmental factors. Distance-based linear models were used to test these species-environment relationships and indicated that eight variables (water temperature, pH, conductivity, waterbody size, habitat type, altitude, hydrological-drainage, climate) individually showed significant correlations with the response ostracod dataset of 35 species. However, owing to substantial collinearity, the most parsimonious model identified only two predicting variables (climatic zone and water pH) which best explained variation in ostracod assemblage composition. The assemblages of the two climatic zones differed significantly, with Plesiocypridopsis newtoni and Sarscypridopsis ochracea being most commonly found in the BS climates, while Sarscypridopsis trigonella and Physocypria capensis occurred most frequently in the Cf climates. Finally, tolerance ranges to water pH and electrical conductivity for 21 ostracod species are provided to facilitate application of ostracods in further biodiversity and water-quality assessments, as well as in palaeo-environmental reconstructions. [ABSTRACT FROM AUTHOR]

The growing demand for fuel in South Africa coupled with the depletion of fossil fuel reserves demonstrates the need for alternative energy sources. A renewable resource such as biomass can be optimized as an energy source. Wastewater sludge and bagasse have the energy potential to produce high calorific value biocoal; this will contribute to the supply of energy in South Africa. The synthesis of biocoal from wastewater sludge and bagasse through an artificial synthetic coal production process, i.e. hydrothermal carbonization, is preferred over other thermal conversion techniques as hydrothermal carbonization is capable of handling feed having a high (75--90%) moisture content. In this study, wastewater sludge and sugarcane bagasse were subjected to hydrothermal carbonization, and the effect of temperature was explored at 180, 210, 240 and 260°C. Variation of the ratio of dry sludge to bagasse of 100:0, 80:20, 60:40, 40:60, 20:80 and 0:100 and the composition of solid to liquid (solid loading wt%) of 1:10, 2:10, 3:10 and 4:10 (SB:H2O) corresponding to 9.09, 16.67, 23.08 and 28.57 wt% loading was investigated. The results obtained in this study reveal that solid loading, temperature, biomass type and ratio variation had a substantial impact on the yield and calorific value of the biocoal produced. The highest biocoal yield of 23.36 wt% was achieved at 210°C and derived from sludge/bagasse with a sludge content of 20%. Across all of the runs, the highest calorific value of 20.21 MJ kg-1 was achieved at 260°C when pure bagasse was employed (0% sludge content). [ABSTRACT FROM AUTHOR]

The rising volume of wastewater sludge and sugarcane bagasse is becoming a prominent concern globally. Furthermore, the growing demand for fuel coupled with the depletion of fossil fuel reserves in South Africa demonstrates the need for alternative energy sources. To minimize the reliance on fossil-based energy sources, a renewable resource such as biomass can be optimized as an energy source. Wastewater sludge and bagasse have the energy potential to produce high-calorific-value biocoal; this will contribute to the supply of energy in South Africa. The synthesis of biocoal from wastewater sludge and bagasse through an artificial synthetic coal production process, i.e., hydrothermal carbonization (HTC), is preferred over other thermal conversion techniques as HTC is capable of handling feed having a high (75–90%) moisture content. This article focuses on the production of biocoal from wastewater sludge and sugarcane bagasse as an alternative to sustainable bioenergy supply and as one of the potential solutions for reducing net CO2 greenhouse gas (GHG) emissions from fossil-fuel power plants, and addresses the use of different thermochemical technologies, previous studies on the composition of wastewater sludge and bagasse, and the benefits of hydrothermal carbonization. [ABSTRACT FROM AUTHOR]

Purpose: An important focus of poststroke rehabilitation is the attainment of community participation. However, several factors may influence participation some of which vary from setting to setting. The aim of this study is to investigate the factors influencing community participation among community-dwelling stroke survivors in the Western Cape, South Africa. Materials and methods: The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) and the Social Support Questionnaire 6 (SSQ6) were the instruments used to collect data. Participant demographics, clinical features and domain-specific scores of the WHODAS 2.0 were used as potential predictors. Correlation analysis and multiple regression models were used to examine determinants of community participation. All assessments were conducted using face-to-face interviews. Results: One hundred and six stroke survivors enrolled in this cross-sectional study. Risk factors, cognition, mobility, self-care, getting along with people, household activities and total WHODAS 2.0 score were associated with participation. Four predictors of community participation were identified from multiple regression, namely mobility (38%), cognition (11%), life activities (4%) and stroke risk factors (1%). Determinants varied by gender and age group. Mobility predominated in males and younger adults, while cognition was more pronounced in females and the elderly. Lastly, the influence of social support on community participation was largely defined by the gender and age of stroke survivors. Conclusion: The findings suggest focusing stroke rehabilitation on important factors such as mobility, cognition, life activities and risk factors to advance patients' participation. It also emphasizes giving specific consideration to key factors specific for gender and age of stroke survivors. Community participation in the general population of stroke survivors' is largely determined by their mobility function. Determinants of community participation among stroke survivors essentially vary according to age and gender. Clinically, this study suggests that focusing on specific determinants of improved community participation according to stroke patients' demographic categories (gender and age) may be an important impetus to enhance rehabilitation outcome. [ABSTRACT FROM AUTHOR]

Intoxication by Moraea pallida Bak. (yellow tulp) in livestock is of great importance in South Africa, ranking top among all plant-induced cardiac glycoside toxicosis. The toxic principle, a bufadienolide, is 1α, 2α-epoxyscillirosidine. Treatment of poisoning is challenging and affected livestock often succumbs due to the stress of handling. Manipulating animals to resist poisoning is a potential management strategy. The goal of this study was to explore the potential to develop a vaccine against epoxyscillirosidine by raising antibodies against epoxyscillirosidine in sheep and to assess the neutralization ability of the antibodies in vitro. Epoxyscillirosidine was successfully conjugated to keyhole limpet haemocyanin (KLH) and bovine serum albumin (BSA) rendering them immunogenic. The sheep, vaccinated with epoxyscillirosidine-KLH conjugate (n = 4) and KLH (n = 2) with Montanide, developed antibodies as determined with an indirect enzyme linked immunosorbent assay (ELISA). Total immunoglobulins from sera of vaccinated and control sheep that were purified and concentrated using ammonium sulphate precipitation were 11,940 and 7850 μg, respectively. The in vitro neutralization assay using the methyl blue tetrazolium bromide (MTT) cell viability assay indicated no significant difference (p > 0.05) between anti-epoxyscillirosidine-KLH and KLH antibodies. Rather, the antibodies seemed to enhance the cytotoxicity of epoxyscillirosidine in H9c2 cells. Thus, it is necessary to develop improved vaccination methods to generate antibodies capable of neutralizing the functional group responsible for epoxyscillirosidine toxicity. • 1α, 2α-Epoxyscillirosidine was conjugated to KLH before using this conjugate to vaccinate sheep to raise antibodies. • Anti-epoxyscillirosidine-KLH antibodies raised were concentrated and purified using ammonium sulphate precipitation. • The neutralization efficacy of antibodies against epoxyscillirosidine was evaluated with the MTT cell viability assay. • There was no difference (p > 0.05) in viability between cells exposed to antibodies from experimental and control sheep. • The antibodies were non-neutralizing but rather enhanced the cytotoxicity of epoxyscillirosidine in vitro. [ABSTRACT FROM AUTHOR]

Purpose: To investigate objectively measured physical activity in stroke survivors living in low-income areas of Cape Town, South Africa, specifically to: (a) describe the volume of daily physical activity and time spent in different intensity levels and (b) investigate the association of factors covering the International Classification of Functioning, Disability and Health with sedentary behavior. Materials and methods: A cross-sectional design was used, where forty-five ambulatory communitydwelling stroke survivors participated. Volume and intensity of physical activity were assessed with accelerometers for three to five consecutive days. Personal and environmental factors, along with body function and activity, were captured. Multiple linear regression was used to investigate factors associated with the percentage of days spent sedentary. Results: The median number of steps per day was 2393, and of the average 703 minutes of wear time, 80% were spent in sedentary, 15% in light, and 5% in moderate-to-vigorous intensity physical activity. Age, stroke severity, and failing to receive outpatient rehabilitation were independently associated with sedentary, which, taken together, explained 52% of the variance. Conclusions: Low volumes of physical activity and high amount of sedentary time emphasize the need to develop strategies that will increase physical activity. Providing outpatient rehabilitation in a systematic manner post-stroke is a potential target of health care programs in order to reduce sedentary behavior. [ABSTRACT FROM AUTHOR]

Background: Myrsine africana (MA) is a plant traditionally used in South Africa to treat various diseases. Objective: The ethanolic extract of MA, was used for in vitro and in vivo studies to determine its elastase inhibitory activity. Materials and Methods: MA and its isolated compound, myrsinoside B, were tested in vitro for their elastase inhibitory activity. The MA extract was also evaluated for mutagenicity using two strains of Salmonella typhimurium (TA 98 and TA 100), microbial count, metal analysis, and stability. In vivo studies included irritancy and wrinkle reduction trials using Visioscan and Visioface. Results: The leaf extract showed good elastase inhibition with a 50% inhibitory concentration (IC50) of 28.04 µg/ml. Myrsinoside B inhibited the elastase enzyme at an IC50 of 4.68 ± 0.34 µg/ml. No colony growth observed during mutagenicity studies and it was concluded that MA ethanolic extract is a nonmutagen. MA extract was found to be a nonirritant during the patch test clinical trial. MA was found to contain negligible amounts of microorganisms and heavy metals. Gel cream containing MA crude extract was found to be stable for 2 years when kept at temperatures below 30°C. In clinical trials (in vivo), it was found that the test product containing 5% ethanolic extract of MA was effective in reducing wrinkles after application 2 times a day for 14 days and 28 days compared to the placebo aqueous cream. Conclusion: MA is effective in reducing the appearance of wrinkles. [ABSTRACT FROM AUTHOR]

The importance of strengthening local governments is widely recognised as local governments face new challenges against the backdrop of global decentralisation processes. Municipal International Cooperation (MIC) contributes strategically to such processes by peer-to-peer learning within existing local institutions, a development process that is both efficient and provides continuity. Empirically, the paper draws upon the findings of an evaluation of the Dutch support programme for MIC called LOGO South. The main conclusion is that partnerships between local authorities do strengthen local governments in the South; the unique approach of the LOGO South programme adds important spillover effects in mutual learning, resulting in both policy transfer and mobility. By creating multilevel governance networks, knowledge circulation was also strengthened. This paper contributes to the debate by showing that locally based, multilevel hybrid networks are strategic for governance processes. [ABSTRACT FROM PUBLISHER]

The article discusses the lessons learnt from the development and implementation of the South African Department of Water Affairs' (DWA) water reconciliation strategies in the Eastern Cape and Western Cape provinces of South Africa. Topics discussed include approaches to maintenance of strategies which include updating of strategies, updating of water requirements scenarios, and water conservation and water demand management (WC/WDM), the status of Western Cape, and the status of Eastern Cape.

Eucalyptus nitensrequires a sufficiently cold winter to produce flower buds. In areas in South Africa whereE. nitenscommercial plantations as well as breeding and production seed orchards are located, winter chilling is often insufficient for floral bud initiation. Hence, under such conditions,E. nitensfloral bud and seed crops are poor and inconsistent. The local industry is almost entirely dependent on paclobutrazol (PBZ) applications for encouraging flowering inE. nitensseed orchards. Between 2008 and 2010, an experiment was conducted to investigate the potential of overhead irrigation (sprinkling) as a means of supplementing winter chilling to improve floral bud production inE. nitens. The treatments included three levels of sprinkling (nil, 10 weeks and 16 weeks duration), two levels of PBZ (nil, 0.025 g a.i. per mm basal stem circumference) and two grafted clones (prolific flowerer and shy-flowerer). Sprinkling reducedE. nitensdaytime bud temperatures by as much as 16.2 °C on warm, dry winter days. In 2009 (cold winter) and 2010 (warm winter), sprinkling increased chilling accumulation by 44% and 72% (nil versus maximum sprinkling), respectively. In 2009, in the absence of PBZ, sprinkling resulted in a higher percentage of trees of either clone producing umbels (flower buds) compared with the control. In the warmer 2010 winter, sprinkling again increased flowering, with the number of flowering shoots and umbels per tree being significantly higher than the control atp< 0.05. In both 2009 and 2010, PBZ showed a strong additive effect to winter chilling onE. nitensfloral bud production. TheE. nitensclone × chilling × PBZ flowering interaction was complex and warrants more detailed investigation in future. Overhead sprinkling offers a practical method of supplementing winter chilling and improving floral bud production in high-chill-requiring temperate eucalypt species such asE. nitens. [ABSTRACT FROM AUTHOR]

The morphological identification of cryptic rodent species has historically been problematic. At best, many cryptic species have been identified by chromosomal differences. However, to study the life histories of such rodent species, there is a need lot a molecular technique for cryptic species identification that does not involve destructive sampling. In this manuscript we examine mitochondrial DNA (mtDNA) cytochrome-b genetic variation in 2 cryptic murid rodent species, the red veld rat (Aethomys chrysophilus) and the Tete reid rat CA. ineptus) from southern Africa. Phytogenetic and phytogeographic analyses of these sequences showed reciprocal monophyly between populations of the 2 species in southern Africa, but no support for monophyly of A. chrysophilus from southern and eastern Africa. This suggests that the analysis of mtDNA can be used to distinguish these 2 sister species in southern Africa. However, these results need to be investigated further by DNA analyses of type specimens, topotypical material, or both from adjacent localities. [ABSTRACT FROM AUTHOR]

Moraea pallida Bak. (yellow tulp) poisoning is the most important plant cardiac glycoside toxicosis in South Africa. The toxic principle, a bufadienolide, is 1α, 2α-epoxyscillirosidine. The aim was to investigate the potential to develop a vaccine against epoxyscillirosidine. Epoxyscillirosidine, proscillaridin and bufalin, were successfully conjugated to hen ovalbumin (OVA), bovine serum albumin (BSA) and keyhole limpet haemocyanin (KLH). There was a low immune response following vaccination of adult male New Zealand White rabbits with epoxyscillirosidine-OVA (n = 3) and OVA (n = 3) using Freund's adjuvant in Trial (T) 1. The immune response improved significantly in T2 following doubling of the dose to 0.8 mg/rabbit and changing the adjuvant to Montanide. In T3, the rabbits (n = 15), allocated into 5 equal groups, vaccinated with proscillaridin-BSA, bufalin-BSA, epoxyscillirosidine-KLH, epoxyscillirosidine-BSA and BSA respectively, using Montanide adjuvant, developed antibodies against the administered immunogens, with epoxyscillirosidine-KLH inducing the highest immune response. Proscillaridin and bufalin antibodies cross-reacted with epoxyscillirosidine in an enzyme linked immunosorbent assay. The conjugation methodology will be adjusted in the future to target optimal conjugation efficiency. Additional vaccination will be conducted in search of neutralizing antibodies against the yellow tulp toxin. The cross-reactivity of proscillaridin and bufalin antibodies with epoxyscillirosidine could be studied in future to explore the potential to prevent yellow tulp poisoning. • Epoxyscillirosidine and the commercially available proscillaridin and bufalin were conjugated to carrier proteins • Antibodies against the bufadienolide haptens epoxyscillirosidine, proscillaridin and bufalin were raised in rabbits • Epoxyscillirosidine-KLH conjugate produced the highest immune response relative to the BSA conjugates • Proscillaridin and bufalin antibodies cross-reacted with epoxyscillirosidine as antigen in an ELISA [ABSTRACT FROM AUTHOR]

Abstract: Avocado fruit are highly variable, and even those graded for similar size and appearance do not behave in the same manner after harvest. This is particularly problematical for those involved in sales to the “ready-ripe” market. These operations are faced with a high variation in the rate of ripening within a consignment, causing logistical difficulties. Fruit water content (or its complement dry matter) has a major impact on-line ripening and has hence been used as the maturity marker in the South African avocado industry. Presently, fruit water content is destructively measured using a representative sample as an indicator of when to post-harvest. In order to investigate if fruit water content and/or abscisic acid triggers fruit ripening, water or ABA was infused into commercially mature, but non-ripe avocado fruit. The fruit ripening, mass, CO2 and ethylene production patterns were determined over the ripening period. By infusing water through the pedicle, the variation in days to ripening was decreased without any effect on the number of days to ripening. ABA infusion hastened ripening but did not affect the variation in days to ripening. It is therefore suggested that the fruit water content at harvest forms the baseline condition from which the trigger for ripening is determined, while post-harvest water loss and ABA modulate and stimulate ripening, respectively. Furthermore, an equation was developed using Near Infrared Spectroscopy (NIRS) to measure mesocarp water content (R 2 =0.92, SE=1.8% MC). It is postulated that on line sorting of fruit using NIRS, based on time to ripen, would result in consignments of fruit with less ripening variation, thereby solving the industry''s logistical problem of fruit which have a wide spread of ripening being packed into one carton. [Copyright &y& Elsevier]

Although historical developments have differently shaped urban growth trajectories of Indian and South African cities, informal settlements continue to present urgent concerns for city governments in both countries. This research explores urban governance and political bargaining of households residing in informal settlements of Chennai, India and eThekwini, South Africa across institutional and geographic scales. The article analyses two relations in a comparative framework of Chennai and eThekwini- 1) between city governments and informal settlements; and 2) livelihoods building strategy of households in relations to the informal settlements. City and settlement relations are explored by discussing the dominant planning discourses, as illustrated in policy-related documents produced by the two city governments. The article reveals that political bargaining utilising different methods forms a crucial strategy to build livelihoods. The multi-scalar analysis of households within their situated contexts reveals how their distinct trajectories of development are closely associated with the urban and settlement histories of which they are a part. The different mandates within which the settlements exist are influential in allowing households to build up their livelihoods over one or two generations. • Comparative analysis of informal settlements across geographical and institutional scales in Chennai and eThekwini. • The article reveals that political bargaining utilising different methods forms a crucial strategy to build livelihoods. • The research shows the influence of urban and settlement histories on development of households in informal settlements. • City governments use matrices and models in planning of informal settlements as a strategy to depoliticize interventions. [ABSTRACT FROM AUTHOR]