11 research outputs found
Quest Volume 9 Number 1
No full textOur changing oceans: Isabelle Ansorge and Mike Roberts explain South Africa's role in investigating the changes; Robots in the ocean Thomas Mtsonti and Isabelle Ansorge explain the global ocean observing system; New ways to study zooplankton: Innovation has changed our understanding of this vital link in the ocean's food chains; Invasive aliens in Antarctica: Even the remote Antarctic continent has problems with invasive alien species; High in the food chain - seals in the Southern Ocean: Three decades of research have given scientists a lot of insight into the importance of seals in the Southern Ocean; A swirly world - measuring ocean currents from the new SA Agulhas II; Tammy Morris, Isabelle Ansorge and Patrick Vianello explain the importance of understanding ocean currents: Gliders in the ocean Africa's first ocean gliders navigate the turbid and remote Antarctic waters; Microbes in the ocean Gerda du Plessis introduces us to microscopic plankton: Life at sea Christopher Jacobs, Jennifer Butler, Mokete Kaogo, Alistair Blair and Marcel du Plessis give an honours student's perspective on life on the SA Agulhas II.Academy of Science of South Africa: Department of Science and Innovatio
Topical delivery of acyclovir and ketoconazole
No full textContext: Viral and fungal cutaneous manifestations are regularly encountered in immunocompromised HIV/AIDS individuals and can be treated by drugs such as acyclovir and ketoconazole, respectively. Objective: The aim of this study was to determine whether the novel Pheroid™ delivery system improved the transdermal delivery and/or dermal delivery of acyclovir and ketoconazole when incorporated into semi-solid formulations. Materials and methods: Semi-solid products (creams and emulgels) containing these drug compounds were formulated, either with or without (control) the Pheroid™ delivery system. The stability of the formulated semi-solid products was examined over a period of six months and included the assay of the actives, pH, viscosity, mass loss and particle size observation. Vertical Franz cell diffusion studies and tape stripping methods were used to determine the in vitro, SC-epidermis and epidermis-dermis delivery of these formulations. Results and discussion: Stability tests showed that none of the formulations were completely stable. Acyclovir showed a biphasic character during the in vitro skin diffusion studies for all the tested formulations. The Pheroid™ cream enhanced the transdermal, SC-epidermis and epidermis-dermis delivery of acyclovir the most. The average amount of ketoconazole diffused over 12 h showed improved delivery of ketoconazole, with the Pheroid™ emulgel exhibiting the best transdermal and epidermis-dermis delivery. Conclusion: The Pheroid™ formulae increased transdermal penetration as well as delivery to the dermal and epidermal skin layers. The Pheroid™ emulgel and the Pheroid™ cream increased the topical delivery of ketoconazole and acyclovir, respectively
Actinobacterial diversity of the Ethiopian Rift Valley lakes
No full text>Magister Scientiae - MScThe class Actinobacteria consists of a heterogeneous group of filamentous, Gram-positive bacteria that colonise most terrestrial and aquatic environments. The industrial and biotechnological importance of the secondary metabolites produced by members of this class has propelled it into the forefront of metagenomics studies. The Ethiopian Rift Valley lakes are characterized by several physical extremes, making it a polyextremophilic environment and a possible untapped source of novel actinobacterial species. The aims of the current study were to identify and compare the eubacterial diversity between three geographically divided soda lakes within the ERV focusing on the actinobacterial subpopulation. This was done by means of a culture-dependent (classical culturing) and culture-independent (DGGE and ARDRA) approach. The results indicate that the eubacterial 16S rRNA gene libraries were similar in composition with a predominance of α-Proteobacteria and Firmicutes in all three lakes. Conversely, the actinobacterial 16S rRNA gene libraries were significantly different and could be used to distinguish between sites. The actinobacterial OTUs detected belonged to both the Rubrobacterales and Actinomycetales orders with members of the genus Arthrobacter being found in all three lakes. Geochemical properties were significantly different between the lakes, although more than one property attributed to the variance between community compositions. The diversity detected in the culture-based study differed significantly and all isolates belonged to the genus Streptomyces. Two novel strains were characterized by means of phylogenetic (16S rRNA gene sequence), physiological, morphological and biochemical analyses. Both novel isolates were capable of growing under "extreme" conditions- pH 12, 10% NaCl and 45°C. Partial enzyme characterization revealed that both strains produced xylanase enzymes that were active at pH 6.5 and 8.5 with an increase in activity up to 45°C. The results obtained revealed a previously undetected diversity of actinobacteria in the Ethiopian Rift Valley with a potentially novel subpopulation adapted to haloalkaline conditions. The low 16S rRNA sequence similarity of a substantial proportion of the libraries suggests that culture-based isolation may play a vital role in deciphering the community fingerprint.The National Research Foundation and the Norwegian Research Counci
Actinobacterial diversity of the Ethiopian Rift Valley lakes
No full text>Magister Scientiae - MScThe class Actinobacteria consists of a heterogeneous group of filamentous, Gram-positive bacteria that colonise most terrestrial and aquatic environments. The industrial and biotechnological importance of the secondary metabolites produced by members of this class has propelled it into the forefront of metagenomics studies. The Ethiopian Rift Valley lakes are characterized by several physical extremes, making it a polyextremophilic environment and a possible untapped source of novel actinobacterial species. The aims of the current study were to identify and compare the eubacterial diversity between three geographically divided soda lakes within the ERV focusing on the actinobacterial subpopulation. This was done by means of a culture-dependent (classical culturing) and culture-independent (DGGE and ARDRA) approach. The results indicate that the eubacterial 16S rRNA gene libraries were similar in composition with a predominance of α-Proteobacteria and Firmicutes in all three lakes. Conversely, the actinobacterial 16S rRNA gene libraries were significantly different and could be used to distinguish between sites. The actinobacterial OTUs detected belonged to both the Rubrobacterales and Actinomycetales orders with members of the genus Arthrobacter being found in all three lakes. Geochemical properties were significantly different between the lakes, although more than one property attributed to the variance between community compositions. The diversity detected in the culture-based study differed significantly and all isolates belonged to the genus Streptomyces. Two novel strains were characterized by means of phylogenetic (16S rRNA gene sequence), physiological, morphological and biochemical analyses. Both novel isolates were capable of growing under "extreme" conditions- pH 12, 10% NaCl and 45°C. Partial enzyme characterization revealed that both strains produced xylanase enzymes that were active at pH 6.5 and 8.5 with an increase in activity up to 45°C. The results obtained revealed a previously undetected diversity of actinobacteria in the Ethiopian Rift Valley with a potentially novel subpopulation adapted to haloalkaline conditions. The low 16S rRNA sequence similarity of a substantial proportion of the libraries suggests that culture-based isolation may play a vital role in deciphering the community fingerprint.The National Research Foundation and the Norwegian Research Counci
Carnegie Library staff, 1967 / Biblioteekpersoneel
No full textBlack and white group photograph.Back row: Danie de Wet, Sarie Conradie, Bessie le Roux, Suzanne le Roux, Dalene van der Riet, Joyce Erasmus, Amelia Louw, _____, Ginnie Ehlers, Brunie Koen.
Middle: Mara Greyling, Maria Kotzé, Christine Theron, Engelise de Villiers, Riette Massyn, P. Nicholas, Margie Albertyn, Rita Combrinck, Miemie Vlok, Cecile Louw, Sylvia Barnard.
Front row: Maxie Bezuidenhout, P. Korkie, Lorinda de Klerk, F. du Plessis, G. Marais, H. Süling, Anna Brink, Gerda van Niekerk, Esther Basson
Formulation, in vitro release and transdermal diffusion of acyclovir and ketoconazole for skin conditions in HIV/AIDS patients
No full textThesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.The aim of this in vitro study was to investigate the efficacy of the novel Pheroid™ technology system in a semi-solid dosage form, for the topical delivery of acyclovir (5% w/w), an anti-viral agent and ketoconazole (2% w/w) an anti-fungal agent.
The human immununodeficiency virus (HIV) had an immense impact on the spectrum of diagnosis of cutaneous diseases since its first manifestation in the late 1970's (Yen-More et al., 2000:432). The skin is the most commonly affected organ in HIV infected individuals with skin manifestations present in up to 92% of HIV-positive patients. According to Ramdial (2000:113) the skin may also be the first or the only organ affected throughout the course of the HIV/AIDS disease. HIV/AIDS patients are more susceptible to infections due to their compromised immune systems (Durden & Elewski, 1997:200) and an exceptionally wide range of infectious skin manifestations presents in HIV/AIDS infected individuals, some of which are viral and fungal. Acyclovir is an anti-viral active against herpes simplex virus type 1 and type 2, varicella-zoster virus, Epstein-Barr virus and the cytomegalovirus (Hayden, 2001:1317). The anti-fungal drug, ketoconazole has activity against the majority of pathogenic fungi which include Candida species and Histoplasma capsulatum (Bennett, 2001:1301). It is appropriate to formulate a topical product containing both acyclovir and ketoconazole because viral and fungal cutaneous manifestations are regularly encountered in combination in HIV/AIDS infected individuals,. This combination topical product may be useful in the treatment of viral and fungal opportunistic skin manifestations. Curing these skin lesions may also assist to improve the state of mind and wellbeing of infected individuals.
The skin, however, acts as a barrier against diffusion of substances through the underlying tissue. The main problem in transdermal and dermal delivery of actives is to overcome the stratum corneum, the skin's natural barrier (Menon, 2002:4). The Pheroid™ delivery system can promote the absorption and increase the efficacy of a selection of active ingredients in dermatological preparations (Grobler et al., 2008:284). The aim of this study was to formulate a stable semi-solid product containing Pheroid™ to determine whether Pheroid™ technology would enhance the flux and/or delivery of acyclovir and ketoconazole to the epidermal and dermal layers of the skin. In vitro studies and tape stripping were used to determine the effect that the Pheroid™ delivery system had on skin permeation of acyclovir and ketoconazole in semi-solid formulations. The formulae containing no Pheroid™ were used as a control against which the efficacy of the formulations containing Pheroid™ was measured. The stability of the formulated semi-solid products was examined over a period of 6 months according to the International Conference of Harmonisation (ICH) Tripartite Guidelines (2003) and the Medicines control council (MCC) of South Africa (2006). The formulated products were stored at three different temperatures. The stability tests included the assay of the actives and other attributes in the formulation, pH, viscosity, mass loss and particle size observation. These tests were conducted at 0, 1, 2, 3 and 6 months. The results demonstrated that the transdermal flux, epidermal and dermal penetration of acyclovir was enhanced by the Pheroid™ cream formulation. Ketoconazole's transdermal flux as well as delivery to the epidermal and dermal layers of the skin was improved by the Pheroid™ emulgel formula. The topical delivery of ketoconazole and acyclovir was thus enhanced by Pheroid™ technology. The Pheroid™ formulations, however, did not meet the requirements for stability according to the ICH and MCC.Master
LIP Woordfeeskoerant 2009
No full textThe LIP Woordfeeskoerant is an independent woordfees festival newspaper
produced by the BPhil (Journalism) class of that specific year in the Department of Journalism, Stellenbosch University.Die Wes-Kaap is ’n vreemde land vir diegene van die ander kant van die Tonnel.
Hier stóp mense by voetoorgange, by vulstasies word jy in Afrikaans bedien en daar is selfs ’n kans dat jy hier ’n regering kan aantref wat nie deur die ANC oorheers word nie. Die tiende jaarlikse Woordfees, aangebied deur die Universiteit van Stellenbosch se departement Afrikaans en Nederlands is eweneens so ’n rare verskynsel. Mense van die land van mynhope en jakarandas is gewoond aan feeste soos Aardklop en selfs die Klein-Karoo Nasionale Kunstefees. Dáár is die Huisgenoot-tent vroeg reeds vol mense met piekniekmandjies of kiste bier en is Dowwe Dolla bo aan die lys van vermaak. Ander drentel van stalletjie tot stalletjie, elkeen met sy eie oorverdowende musiek. Mnr Eduard Rosenstrauch, die Woordfees se projekbestuurder, sê dit is juis nie die doel van die Eikestadfees nie. “Ons probeer spesifiek nie die stalletjies en goed, daai straatfees namaak nie. Dit wat ons Saterdag doen, is op ’n baie kleiner skaal sodat mense nie vertrap word nie.” André P. Brink het as spreker by die opening van die Woordfees aangedui dat daar deesdae feeste agter elke bos en klip is. Die belangrike Afrikaanse skrywer het verduidelik waarom veral die Woordfees dus so belangrik is om taal te bevorder. Hy het die verhaal vertel van ’n jong seun in ’n Nazi-konsentrasiekamp wat beveel is om ’n skoenlapper te teken. Die seun skryf toe eenvoudig dat hy geen skoenlappers kon sien nie. “Ons enigste antwoord op die donker samelewing is die woord,” sê
Brink. En so het die fees van 2009 steeds gefokus op die woord, veral die Afrikaanse woord. Skrywers het soos gewoonlik voorgelees en onderhoude gevoer, maar dit was in Aan Tafel wat feesgangers regtig nader aan die skrywers en kunstenaars gebring is. Hier is middagete of aandete geniet terwyl onderhoude rondom die tafel met die verskillende persoonlikhede gevoer is. Die gehoor het ook later kans gekry om vrae te stel. Interaksie, interaksie... Woorde bestryk ook ander kunsvorme en hiervan het die fees deeglik kennis gegee. Debatte met
denkers en meningsvormers, die Sanlam-dramafees, ’n verskeidenheid digkuns, lirieke en musiek was deel van die aanbod. Al die groot name in die Afrikaanse
kunswêreld, met die waarskynlike uitsondering van Steve, het op die program verskyn. Om alles te kroon, het vanjaar se fees saamgeval met ’n hele paar
belangrike verjaarsdae, waaronder dié van Hennie Aucamp en PG du Plessis wat albei 75 word, en Chris Barnard 70. Die Woordfees is vanjaar 10 jaar oud met “lag-lag” as die hooftema. Hulle wou meer komedie in vanjaar se fees hê, het Rosenstrauch gesê, want baie mense het deesdae ’n goeie rede nodig om te kan lag. Hieraan het Uys Krige se klassieke teaterproduksie, Die Ryk Weduwee, wat as die fees se vlagskip-produksie beskou word, volkome voldoen. Dit is egter ’n fout dat die fees net gemik is op ’n verfynde, uitgelese minderheid. Die fees het genoeg vermaak gebied om ook die studente te lok. Volgens Rosenstrauch is dit ’n probleem vir die Woordfees en die universiteit in sy geheel dat die studente onverskillig teenoor die fees staan. Dit is ondanks goedkoop kaartjies. “Studente sê hulle’t nooit geld nie, maar dan gaan kuier hulle buitendien elke Vrydagaand,” meen hy. Oor die toekoms van die fees het
Rosenstrauch gesê ’n groot besluit wag op die feesdirekteure. Dit kan of sy klein formaat behou of dit kan ’n groot “doef-doef”-fees word. Hoe dit ookal sy, ’n mens kan nie anders nie as om optimisties te voel dat juis hierdie fees die versoenings- of eenheidsfees kan word wat die land so nodig het. Dit nou te oordeel aan baanbrekende produksies soos Dig Deep Paseka and Refiloe-Hape wat vanjaar by die fees te sien was. Antjie Krog, een van Afrikaans se uitsonderlikste woordkunstenaars, het vir dié woordmusiekopvoering tradisionele Sotho-liedjies en gedigte in Afrikaans vertaal. (Lees gerus op
bl. 4 Olebogeng Molatlhwa se stuk oor dié produksie.) En dalk moet ’n mens volstaan met die woorde van prof Russel Botman, rektor van die US: “Dis laglag
vorentoe, nie agtertoe nie.
Stellenbosch Media Forum 2009
No full textStellenbosch Media Forum is an annual publication written and produced by the BPhil (Journalism) class of that specific year in the Department of Journalism, Stellenbosch University.Like those little green booklets that contain the most basic details about
people's lives, the media also document and capture the building blocks of the abstract structure we call identity. But while an ID book is a terse, practically static collection of bits of personal information, identity itself is complex, layered and fluid.
This edition of SMF explores the relationship between identity construction and the media. Among others, the media's portrayals of Afrikaners, rural communities and gay women are examined. These articles strive to give insight into different media's projections of groups and individuals to their audiences.
Reflecting on the media's effect on identity is like casting a stone on the smooth surface of a sheltered pond. The splash, or point of impact, represents the core idea: identity and the media. Then the rippleeffect ensues, causing an ever-expanding circle of related concepts to form around the central notion. Representation, stereotyping, over-simplification, image... These are but a few of the phenomena present in feeding people's notions on identity.
The media, from fictional entertainment on one end of the spectrum to factdriven news on the other, have a profound influence on the manner in which people experience the world. Throw in a multitude of agendas, political affiliations and ideological motives, and it becomes clear that constructing identity through the media is never a totally innocent or objective endeavour.
Die metaforiese poel is egter meer soos 'n sement plaasdam. Die golfies bereik naderhand die sementrand, slaan daarteen vas en begin weer na binne beweeg. Op dieselfde manier is die media ook nie 'n eenrigtingstroom wat slegs idees oor identiteit projekteer nie. Die omgewing waarin media-instellings gesetel is, het ook 'n wesenlike invloed op die wyse waarop hulle hulself oriënteer.
Hierdie wisselwerking kom neer op die volgende: Mense koop 'n bepaalde mediaproduk, soos 'n koerant, omdat dit die gebeure en mense in hul lewens op 'n manier skets wat vir hulle toeganklik en aanvaarbaar is. Op sy beurt spits die koerant hom toe op die tipe lesers wat die produk ondersteun. Hierdie lesers skep deur 'n reeks interaksies en invloede hul eie standaarde van toeganklikheid en aanvaarbaarheid. Neem die redaksie nie hierdie gegewens in ag nie, vervreem hy homself van sy mark.
Soos mens kan sien in die artikels oor Caster Semenya, Hamas en vroulike moordenaars, om 'n paar te noem, word etikette aan mense en groepe geheg. Die media speel klaarblyklik 'n groot rol in die oordra van sulke etikette.
Terselfdertyd word Die Burger, die Son en e-tv soms gerespekteer, en soms geminag, afhangende deur wie se oë elkeen beskou word. En ook hulle moet hul identiteit soms aanpas om te bly inpas in 'n veranderende mediawêreld.
'n Sirkel het immers geen beginpunt of einde nie. Deur 'n bepaalde identiteit aan mense en gebeure te heg, skep die verskeidenheid media wat verantwoordelik is vir die oordra van inligting, ook 'n identiteit vir hulself.
Hierdie uitgawe van SMF se identiteit is geheg aan besprekings oor identiteitskepping in beide rigtings. Enjoy
