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FIGURE 1 in Two new species of Trachyandra sect. Liriothamnus (Xanthorrhoeaceae, Asphodeloideae) from the Western and Eastern Cape Provinces of South Africa
No full textFIGURE 1. Type specimen of Trachyandra eriocarpa.Published as part of Boatwright, James Stephen & Manning, John Charles, 2013, Two new species of Trachyandra sect. Liriothamnus (Xanthorrhoeaceae, Asphodeloideae) from the Western and Eastern Cape Provinces of South Africa, pp. 59-65 in Phytotaxa 155 (1) on page 61, DOI: 10.11646/phytotaxa.155.1.5, http://zenodo.org/record/510094
Systematics of subtribe anthosperminae and the generic affinities of anthospermum l. and nenax gaertn. (Rubiaceae: Anthospermeae)
No full textThe last taxonomic treatment of the subtribe Anthosperminae Benth. (Rubiaceae, Rubioideae, Anthospermeae) was in 1986 by Puff., nevertheless, few attempts have been made to resolve the phylogeny and the inter- and infrageneric relationships within the subtribe. The genera Anthospermum L. (39 species) and Nenax Gaertn. (11 species) are considered the most difficult groups to distinguish. Anthospermum species are widely distributed in Sub-Saharan Africa and Madagascar with the highest concentration of taxa in southern Africa, while Nenax species are restricted to southern Africa, in the south-western Cape Floristic Region. The two genera share common morphological and anatomical characters such as the growth form, presence of hairs on the stem, leaf arrangement, presence of petioles, flowers formation, dehiscence and presence of carpophore in fruits. currently combination of characters, woody shrub, needle-like leaves, few-flowered inflorescence and dioecy are considered unique in Nenax
Chemical investigation of some species of Amaryllidaceae from the Greater Cape Region of South Africa as a source of bioactive compounds
Get PDFPhilosophiae Doctor - PhDThe family Amaryllidaceae is widely distributed in the southern hemisphere. Members of the family are well known for their content of pharmacologically active alkaloids and represent an important epicentre of Amaryllidaceae-alkaloid diversity. Other metabolites from Amaryllidaceae, such as phenolics including flavonoids, lignans, chromones, and acetophenones, in addition to terpenoids and ceramides have been reported. Boophone haemanthoides (BHE), Crossyne flava (CRO), Clivia miniata (CME) and Nerine humilis (NHE) are members of Amaryllidaceae that have shown biological activity. Parkinson’s disease (PD) is a neurodegenerative disease that progresses with increasing age and some of its major symptoms include tremors, postural and movement related difficulties. To date, the treatment of PD remains a challenge because available drugs only treat the symptoms of the disease or possess serious side effects. In light of this, new treatment options are needed, hence this study investigates the neuroprotective effects of BHE and CRO along with the isolated compounds of BHE and CRO
Chemical investigation of some species of Amaryllidaceae from the Greater Cape Region of South Africa as a source of bioactive compounds
No full textPhilosophiae Doctor - PhDThe family Amaryllidaceae is widely distributed in the southern hemisphere. Members of the family are well known for their content of pharmacologically active alkaloids and represent an important epicentre of Amaryllidaceae-alkaloid diversity. Other metabolites from Amaryllidaceae, such as phenolics including flavonoids, lignans, chromones, and acetophenones, in addition to terpenoids and ceramides have been reported. Boophone haemanthoides (BHE), Crossyne flava (CRO), Clivia miniata (CME) and Nerine humilis (NHE) are members of Amaryllidaceae that have shown biological activity. Parkinson’s disease (PD) is a neurodegenerative disease that progresses with increasing age and some of its major symptoms include tremors, postural and movement related difficulties. To date, the treatment of PD remains a challenge because available drugs only treat the symptoms of the disease or possess serious side effects. In light of this, new treatment options are needed, hence this study investigates the neuroprotective effects of BHE and CRO along with the isolated compounds of BHE and CRO
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
An assessment of the current status and invasive potential of Crotalaria agatiflora (Crotalarieae, Fabaceae) in South Africa
Get PDFM.Sc. (Botany)Abstract: Crotalaria agatiflora is native to tropical East Africa (Tanzania, Ruanda, Burundi, Kenya and Ethiopia). In South Africa this plant was introduced as an ornamental garden shrub, and has since become invasive in many localities (savanna, grasslands, watercourses and forest margins). It is found along road verges, riparian areas, dump sites and abandoned sites in Limpopo, Gauteng, Mpumalanga, KwaZulu-Natal and one population in both the Eastern and Western Cape. This project aimed to see whether it poses a significant threat to the biodiversity and ecosystems of the country, so that information can be provided for developing a good management plan for clearing C. agatiflora in South Africa. More than thirty populations of this species were recorded in the country and mapped. Five populations were selected to measure and count the number of individuals, analyse the soil to determine the seed bank and test the seeds for viability and germination ability. The potential future distribution of the species was modelled based on climatic suitability using MaxEnt to visualise the potential suitable range and ArcGIS to calculate (quantify) the expansion or reduction range of suitability between the current and future climate conditions. The Australian weed risk assessment model was also used to score (quantify) the invasiveness of this species. Furthermore, isozyme studies were done to determine whether a single or multiple introductions are responsible for the presence of this species in South Africa. The soil-stored seed bank and records of occurrence show that C. agatiflora is a slow but persistent invader. Its seed coat dormancy and ability to re-sprout makes it very persistent. Seed germination tests showed 100% viability. A very high potential of invasiveness was indicated by the Australian weed risk assessment and the climate suitability models. The isozyme study showed no variation between populations indicating that the species has most likely spread from a single introduction. The scientific data obtained from this study show that C. agatiflora poses a significant threat to the flora of South Africa and that it should be controlled. The data will inform management plans of the Invasive Species Programme of the South African Biodiversity Institute
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Systematic studies of the genus Lebeckia and related genera of the tribe Crotalarieae (Fabaceae)
Get PDFPh.D.Relationships within the Crotalarieae are explored using DNA sequences (ITS and rbcL) and morphological data and the monophyly of the various genera is assessed. A literature review of chemical characters (mainly alkaloids) was needed in order to evaluate the congruence between molecular, morphological and chemical data and how these patterns should be interpreted within the context of new generic and suprageneric concepts. The DNA study was also aimed at confirming the suspected polyphyly of Lebeckia and Lotononis (as currently circumscribed) and at improving generic circumscriptions. The aim was to propose and formalize new generic concepts for Lebeckia s.l. and Lotononis s.l. in order to ensure that all of the resultant genera are monophyletic
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