Search results for "AFRICA"
showing 10 items of 962 documents
“Historical fiction is back”: (Non)Fictional Pasts and Presents in Fred Khumalo’s metahistorical romance, The Longest March
2023
International audience; This article examines the ways Fred Khumalo’s second historical novel, The Longest March, blends different genres – from the use of gothic tropes to the rewriting of historical romances – to reflect on both the fabricated and limited nature of narrative, as well as its necessity in the South African context. The article concludes that The Longest March qualifies as a “metahistorical romance”, as it blurs the boundary between fiction and nonfiction while questioning historical discourse.
Nuovi dati sulla fauna a "grandi branchiopodi" (Branchiopoda: Anostraca, Notostraca, Spinicaudata) delle acque temporanee della Tunisia
2011
Nonostante i primi studi sulla fauna a grandi branchiopodi (Anostraca, Notostraca e Spinicaudata) della Tunisia risalgano alla fine del XIX secolo, ad oggi non esiste un inventario completo ed aggiornato di questi organismi nella regione. Al fine di fornire un quadro organico e quanto più possibile completo, una serie di campagne di campionamento sono state condotte a partire dal 2004. Circa 240 corpi idrici temporanei, distribuiti in tutto il territorio Tunisino e nelle sue isole maggiori (Kerkennah e Djerba), sono stati campionati ripetutamente in inverno e primavera e sono stati raccolti dati sulla morfometria dei bacini e sulle principali caratteristiche fisiche e chimiche delle acque. …
Novel Acylated Triterpene Glycosides from Muraltia heisteria
2002
Four new acylated triterpene glycosides (1-4) have been isolated as two inseparable mixtures of the trans- and cis-3,4,5-trimethoxycinnamoyl derivatives (1,2 and 3,4) from the roots of Muraltia heisteria. The structures of these compounds were elucidated by various 1D and 2D NMR techniques, including (1)H and (13)C, COSY, NOESY, HSQC, TOCSY, and HMBC experiments and FABMS. Compounds 3 and 4 were shown to be cytotoxic in a human colon cancer cell line but did not show any ability to potentiate in vitro cisplatin cytotoxicity.
Cytotoxic bufadienolides from the leaves of a medicinal plant Melianthus comosus collected in South Africa.
2020
Abstract From the leaves of South African medicinal plant Melianthus comosus, four previously undescribed bufadienolides, 16β-formyloxymelianthugenin (1), 2β-acetoxymelianthusigenin (2), 2β-hydroxy-3β,5β-di-O-acetylhellebrigenin (3), and 2β-acetoxy-5β-O-acetylhellebrigenin (4) were isolated together with two known bufadienolides. The structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy, high-resolution mass spectrometry, and other spectroscopic methods. The relative configurations were determined by single-crystal X-ray crystallography analysis and NOESY correlations. The isolated compounds displayed strong cytotoxicity against MCF-7 breast cancer cells, sensitive…
Mbandakamine-Type Naphthylisoquinoline Dimers and Related Alkaloids from the Central African Liana Ancistrocladus ealaensis with Antiparasitic and An…
2018
Four new dimeric naphthylisoquinoline alkaloids, michellamine A5 (2) and mbandakamines C–E (4–6), were isolated from the Congolese plant Ancistrocladus ealaensis, along with the known dimer mbandakamine A (3). They represent constitutionally unsymmetric dimers, each consisting of two 5,8′-coupled naphthylisoquinoline monomers. While the molecular halves of michellamine A5 (2) are linked via C-6′ of both of the naphthalene moieties, i.e., via the least-hindered positions, so that the central biaryl axis is configurationally unstable and not an additional element of chirality, the mbandakamines 3–6 possess three consecutive stereogenic axes. Their monomeric units are linked through an unprece…
Lattice-particle simulation of stress patterns in a Rwenzori-type rift transfer zone
2011
Abstract A new 3D spring lattice computer model has been developed and used to calculate the stress-field in the vicinity of a rift transfer zone. The numerical setup is based on the Rwenzori block, a transfer zone in the Western Branch of the East African Rift Valley. The study has two closely related, yet independent aims: primarily to gain insight into the pattern and the causes of the stress field in the Rwenzori area. The second aim is the evaluation of the model itself, based on a comparison of the model results with local geological structures. The simulations calculate the stress in the brittle part of the crust, at the topographic surface and at a depth of 10 km. The model does the…
Association of Urogenital Symptoms with History of Water Contact in Young Women in Areas Endemic for S. haematobium. A Cross-Sectional Study in Rural…
2016
Female genital schistosomiasis is a neglected tropical disease caused by Schistosoma haematobium. Infected females may suffer from symptoms mimicking sexually transmitted infections. We explored if self-reported history of unsafe water contact could be used as a simple predictor of genital schistosomiasis. In a cross-sectional study in rural South Africa, 883 sexually active women aged 16–22 years were included. Questions were asked about urogenital symptoms and water contact history. Urine samples were tested for S. haematobium ova. A score based on self-reported water contact was calculated and the association with symptoms was explored while adjusting for other genital infections using m…
Strontium and argon isotopic homogenization of pelitic sediments during low-grade regional metamorphism: The pan-African upper Damara sequence of Nor…
1979
Abstract The fine mineral fractions extracted from pelitic sediments of the Eocambrian upper Damaran Mulden Group were subjected to a detailed isotopic study by the Rb-Sr and K-Ar methods in combination with a mineralogical analysis by X-ray diffractometry. The sediments contain two major parageneses of metamorphic origin which can be related to two separate low-grade regional metamorphic events of anchizonal intensity with temperatures between 250 and 300°C and pressures up to 2 kbar. These events are dated at about 535 m.y. and 455 m.y. respectively (with λ( 87 Rb) = 1.42 × 10 −11 yr −1 ). Anomalously high K-Ar ages on samples from specific stratigraphic horizons can be related to open sy…
First morphogenetic analysis of parasite eggs from Schistosomiasis haematobium infected sub-Saharan migrants in Spain and proposal for a new standard…
2021
International audience; Schistosomiasis is a Neglected Tropical Disease caused by trematode species of the genus Schistosoma. Both, autochthonous and imported cases of urogenital schistosomiasis have been described in Europe. The present study focuses on eggs, considered pure S. haematobium by genetic characterisation (intergenic ITS region of the rDNA and cox1 mtDNA). A phenotypic characterisation of S. haematobium eggs was made by morphometric comparison with experimental populations of S. bovis and S. mansoni, to help in the diagnosis of S. haematobium populations infecting sub-Saharan migrants in Spain. Analyses were made by Computer Image Analysis System (CIAS) applied on the basis of …
The Education Production Function reviewed in the framework of Education For All in Sub-Saharan Africa: from theoretical and methodological bounds to…
2007
The Coleman report (1966) was the first of numerous researches exploring quality of learning determinants analysis. With the Education Production Function (EPF), economists have greatly contributed to the extension of this research domain. Actually, empirical works are leading the field with important methodological debates which have fuelled controversies (Hanushek, 2003; Krueger, 2003). Thus, methodological issues have particularly rallied researchers' interests on empirical estimations, while academic researches on the renewal of the theoretical framework have remained scarce despite obvious bounds. Without contesting the validity of miscellaneous estimation problems and the necessity of…