The Effects of Chemical and Mechanical Control of Woody Plants on Resprouting and Seedling Production in Communal Rangelands

In many African countries, communal rangelands are threatened by woody plant encroachment. We sought to explore potential solutions for communal ranchers that would be cost-effective. We conducted two field experiments to determine (1) the effects of various tree removal treatments (10%, 20%, 50%, 75% and 100%), and herbicide application on resprouting ability and vigour of several woody plant species; and (2) the effectiveness of Tree Poppers® (a weed wrench) as a low-cost mechanical control tool to physically uproot seedlings and saplings of woody species. In the first experiment, we examined 12 plant species from 20 plots (30 m x 30 m) each subjected to tree removal, followed by herbicide application on half of the stumps for each plot. In the second experiment, eight dominant tree species were grouped into three height classes (0-49 cm, 50-99 cm, 100-150 cm) of ten seedlings and saplings per species per height class. All the tree species in this study resprouted six months after cutting. Herbicide application significantly reduced the resprouting ability of Dichrostachys cinerea (L.) Wight & Arn, Ehretia rigida (Thunb.) Druce, Vachellia robusta (Burch.) Kyalangalilwa & Boatwright and Ziziphus mucronata Willd. Tree removal positively influenced the resprouting ability and vigour of only Euclea crispa (Thunb.) Gürke. The diameter of stumps was an important factor in determining resprouting ability, with shoot production decreasing with increasing stump diameter. We found no significant differences in the number of seedlings and saplings uprooted by Tree Poppers® among the different size classes. There were significant differences in the number of juveniles uprooted using a weed wrench with only a few individuals of Vachellia species uprooted. Woody plants are more likely to resprout and survive as juveniles than as adults after cutting. Communal ranchers may mechanically control shallow-rooted tree seedlings with a weed wrench but not deep-rooted ones, such as Vachellia species

Collection Priorities of Pasture Genetic Resources in the Paniceae Native to South Africa

There is an urgent need for the prioritization and ex situ conservation of pasture grass species. Many pasture grasses are still in the process of domestication and grasslands in the tropical, subtropical, semi-arid and arid regions of the world are therefore a major source of genetic material for future forage improvement. Within South Africa, it was found that the Paniceae contains several species with high pasture value and that many populations of these species are found in water-limited environments. Therefore, it was proposed that a strategy be developed for the South African National Forage Genebank to prioritize efforts to collect and conserve seed of grass species within the Paniceae, focussing especially on those species in genera Anthephora, Brachiaria, Digitaria, Panicum and Setaria located in areas receiving less than 600 mm of annual precipitation

Cutaneous myiasis: is Lucilia cuprina safe and acceptable for maggot debridement therapy?

Preservation of viable tissue is important in wound management. It is achieved by small, incremental removal of devitalised, necrotic and infected tissues. Maggot debridement therapy (MDT) is used in septic necrotic wounds that fail to respond to conventional modalities. MDT has relied on Lucilia cuprina, which consumes only necrotic tissues, as opposed to Lucilia cuprina, which devours both flesh and necrotic tissues. Recent findings have shown that L. cuprina consumes mainly necrotic and very small amounts of viable tissues and may be used in MDT where L. sericata is very rare or absent. Here we describe wound healing in a patient from rural South Africa with cutaneous myiasis. Our findings agree with workers who indicated that L. cuprina could be used in MDT

Appropriate indications for positron emission tomography/computed tomography, 2015

These recommendations are intended to serve an important and relevant role in advising referring physicians on the appropriate use of 18F-fluorodeoxyglucose (18F-FDG) and non-18F-FDG positron emission tomography/computed tomography (PET/CT), which can be a powerful tool in patient management in oncology, cardiology, neurology and infection/inflammation. PET is a non-invasive molecular imaging tool that provides tomographic images and quantitative parameters of perfusion, cell viability, proliferation and/or metabolic activity of tissues. These images result from the use of different substances of biological interest (sugars, amino acids, metabolic precursors, hormones) labelled with positron-emitting radionuclides (PET radiopharmaceuticals). Fusion of the aforementioned important functional information with the morphological detail provided by CT as PET/CT provides clinicians with a sensitive and accurate one-step whole-body diagnostic and prognostic tool, which directs and changes patient management. Hence PET/CT is currently the most widely used molecular imaging technology for a patient-tailored treatment approach. In these recommendations we outline which oncological and non-oncological indications are appropriate for PET/CT. Once each combination of pathology and clinical indication is defined, a recommendation is given as: 1. Recommended; 2. Recommended in select cases; 3. May be considered; or 4. Not recommended.http://www.samj.org.zaam2016Nuclear Medicin

South African HIV-1 Subtype C Transmitted Variants With A Specific V2 Motif Show Higher Dependence On aα4β7 For Replication

Background: The integrin aα4β7 mediates the trafficking of immune cells to the gut associated lymphoid tissue (GALT) and is an attachment factor for the HIV gp120 envelope glycoprotein. We developed a viral replication inhibition assay to more clearly evaluate the role of aα4β7 in HIV infection and the contribution of viral and host factors. Results: Replication of 60 HIV-1 subtype C viruses collected over time from 11 individuals in the CAPRISA cohort were partially inhibited by antibodies targeting aα4β7. However, dependence on aα4β7 for replication varied substantially among viral isolates from different individuals as well as over time in some individuals. Among 8 transmitted/founder (T/F) viruses, aα4β7 reactivity was highest for viruses having P/SDI/V tri-peptide binding motifs. Mutation of T/F viruses that had LDI/L motifs to P/SDI/V resulted in greater aα4β7 reactivity, whereas mutating P/SDI/V to LDI/L motifs was associated with reduced aα4β7 binding. P/SDI/V motifs were more common among South African HIV subtype C viruses (35%) compared to subtype C viruses from other regions of Africa

Social representations and the politics of participation

Recent work has called for the integration of different perspectives into the field of political psychology (Haste, 2012). This chapter suggests that one possible direction that such efforts can take is studying the role that social representations theory (SRT) can play in understanding political participation and social change. Social representations are systems of common-sense knowledge and social practice; they provide the lens through which to view and create social and political realities, mediate people's relations with these sociopolitical worlds and defend cultural and political identities. Social representations are therefore key for conceptualising participation as the activity that locates individuals and social groups in their sociopolitical world. Political participation is generally seen as conditional to membership of sociopolitical groups and therefore is often linked to citizenship. To be a citizen of a society or a member of any social group one has to participate as such. Often political participation is defined as the ability to communicate one's views to the political elite or to the political establishment (Uhlaner, 2001), or simply explicit involvement in politics and electoral processes (Milbrath, 1965). However, following scholars on ideology (Eagleton, 1991; Thompson, 1990) and social knowledge (Jovchelovitch, 2007), we extend our understanding of political participation to all social relations and also develop a more agentic model where individuals and groups construct, develop and resist their own views, ideas and beliefs. We thus adopt a broader approach to participation in comparison to other political-psychological approaches, such as personality approaches (e.g. Mondak and Halperin, 2008) and cognitive approaches or, more recently, neuropsychological approaches (Hatemi and McDermott, 2012). We move away from a focus on the individual's political behaviour and its antecedents and outline an approach that focuses on the interaction between psychological and political phenomena (Deutsch and Kinnvall, 2002) through examining the politics of social knowledge

Talking South African fathers: a critical examination of men’s constructions and experiences of fatherhood and fatherlessness

The absence of biological fathers in South Africa has been constructed as a problem for children of both sexes but more so for boy-children. Arguably the dominant discourse in this respect has demonized non-nuclear, female-headed households. Fathers are constructed as either absent or ‘bad’. Thus it has become important to explore more closely how male care-givers have been experienced by groups of men in South Africa. This article examines discourses of fatherhood and fatherlessness by drawing on qualitative interviews with a group of 29 men who speak about their reported experiences and understandings of being fathered or growing up without biological fathers. Two major and intertwined subjugated discourses about adult men’s experiences of being fathered that counter- balance the prevailing discourses about meaning of fatherhood and fatherlessness became evident, namely, ‘being always there’ and ‘talking fatherhood’. The importance of the experience of fatherhood as ‘being there’, which relates to a quality of time and relationship between child and father rather than physical time together, is illustrated. It is not only biological fathers who can ‘be there’ for their sons but also social fathers, other significant male role models and father figures who step in at different times in participants’ lives when biological fathers are unavailable for whatever reason. Second, many positive experiences of fathers or father figures that resist a traditional role of authority and control and subscribe to more nurturant and non-violent forms of care, represented as ‘talking’ fathers, are underlined. If we are to better understand the impact of colonial and apartheid history and its legacy on family life in contemporary society, there is a need for more historically and contextually informed studies on the meaning of fatherhood and fatherlessness.Web of Scienc

Obligation to family during times of transition: care, support and the response to HIV and AIDS in rural South Africa

In rural South Africa, high HIV prevalence has the potential to affect the care and support that kin are able to provide to those living with HIV. Despite this, families seem to be largely resilient and a key source of care and support to family affected by HIV. In this article, we explore the motivations for the provision of care and support by kin. We use the results of a small-scale in-depth qualitative study conducted in 10 households over 6 months in rural KwaZulu-Natal, South Africa, to show that family obligation and conditional reciprocity operate in varying degrees and build social capital. We highlight the complexity of kin relations where obligation is not guaranteed or is limited, requiring the consideration of policy measures that provide means of social support that are not reliant on the family