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Floral resources of Apis mellifera capensis in the fynbos biome in the Eastern Cape Province, South Africa

  • Authors: Addi, A , Phillipson, P , Hepburn, H Randall
  • Date: 2006
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451845 , vital:75081 , https://hdl.handle.net/10520/EJC32660
  • Description: The plant species utilized by Cape honeybees, Apis mellifera capensis, as primary nectar and pollen sources were studied in the Eastern Cape Province in an area where fynbos vegetation mingles with grassland communities. From direct field observations and analyses of pollen loads collected by foragers, 54 plant species were identified as nectar and pollen sources. Of 37 endemic and exotic pollen source plants, Metalasia muricata, Eucalyptus grandis, E. camadulensis, Erica chamissonis, Helichrysum odoratissimum, H. anomalum, Crassula cultrata and Acacia longifolia were dominant species.
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  • Date Issued: 2006

Structural and optical properties of alloyed quaternary CdSeTeS core and CdSeTeS/ZnS core–shell quantum dots

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello , Forbes, Patricia B C
  • Date: 2015
  • Language: English
  • Type: Article
  • Identifier: vital:7244 , http://hdl.handle.net/10962/d1020248
  • Description: Synthesis of fluorescent alloyed quantum dots (QDs) with unique optical properties suitable for a wide array of chemical, physical and biological applications is of research interest. In this work, highly luminescent and photostable alloyed quaternary CdSeTeS core QDs of two different sizes were fabricated via the organometallic hot-injection synthetic route. Characterization of the nanocrystals were performed using TEM, XRD, UV/vis and fluorescence spectrophotometric techniques. We have demonstrated in this work that the well fabricated alloyed quaternary CdSeTeS core QDs possess unique optical properties that are advantageous over conventional core/shell systems. Formation of the CdSeTeS/ZnS core/shell with the desired optical properties comes with a number of challenges, hence the advantages of the quaternary alloyed core over the core/shell QDs are (i) avoidance of the challenging process of determining the proper shell thickness which can provide the desired optical properties in the core/shell system and (ii) avoidance of the lattice-induced mismatch between the core and the shell material which can either lead to incomplete exciton confinement or dislocation at the core/shell interface. , Original publication is available at http://dx.doi.org/10.1016/j.jallcom.2015.05.083
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  • Date Issued: 2015

Optical properties of water-soluble l-cysteine-capped alloyed CdSeS quantum dot passivated with ZnSeTe and ZnSeTe/ZnS shells

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello , Forbes, Patricia B C
  • Date: 2015
  • Language: English
  • Type: Article
  • Identifier: vital:7260 , http://hdl.handle.net/10962/d1020269
  • Description: Alloyed quantum dots (QDs) passivated with shell materials have valuable optical characteristics suitable for a wide array of applications. In this work, alloyed ternary CdSeS QDs passivated with ZnSeTe and ZnSeTe/ZnS shells have been synthesized via a hot-injection method and a ligand exchange reaction employing l-cysteine as a thiol ligand has been used to obtain these water-soluble nanocrystals for the first time. The photoluminescence (PL) quantum yield (QY) of alloyed l-cysteine-capped CdSeS was 71.2% but decreased significantly to 5.2% upon passivation with a ZnSeTe shell. The red shift in PL emission of the CdSeS/ZnSeTe QDs was attributed to be strain-induced whilst a lattice-induced process likely created defect states in the core/shell interface hence contributing to the decline in the PL QY. Nonetheless, the fluorescence stability of CdSeS/ZnSeTe QDs in aqueous solution was unperturbed. Further passivation with a ZnS shell (CdSeS/ZnSeTe/ZnS) improved the PL QY to a value of 58.7% and thus indicates that the defect state in the QDs core/shell/shell structure was reduced. PL lifetime exciton measurements indicated that the rates of decay of the QDs influenced their photophysical properties. , Original publication is available at http://dx.doi.org/10.1016/j.optmat.2015.05.024
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  • Date Issued: 2015

Synthesis and anti-parasitic activity of C-benzylated (N-arylcarbamoyl) alkylphosphonate esters

  • Authors: Adeyemi, Christiana Modupe , Isaacs, Michelle , Mnkandhla, Dumisani , Krause, Rui W M , Klein, Rosalyn , Hoppe, Heinrich C , Lobb, Kevin A , Kaye, Perry T
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/125641 , vital:35803 , https://doi.org/10.1016/j.tet.2017.01.045
  • Description: Unexpected substituent-dependent regioselectivty challenges in the synthesis of C-benzylated (N-arylcarbamoyl)phosphonate esters have been resolved. The C-benzylated N-furfurylcarbamoyl derivative showed low micromolar PfLDH inhibition, while one of the C-benzylated N-arylcarbamoyl analogues was active against Nagana Trypanosoma brucei parasites which are responsible for African trypanosomiasis in cattle.
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  • Date Issued: 2017

AIA's Southern Africa Chronicle - Volume VIII No.3

  • Authors: Africa Information Afrique (AIA)
  • Date: 1995
  • Subjects: AIA
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/169401 , vital:41746
  • Description: Machipanda, February 3,1995 (AIA/Brian Latham)—Many Zimbabwean peasants have quietly found the solution to land shortages by crossing into neighbouring Mozambique where it is plentiful. For as little as US$ 10 a field, they are acquiring land and a place to live — probably illegally — from chiefs and headmen across the border. Information on how to get land is easily accessible in Machipanda, the Mozambique border town at the head of the Beira Corridor from Zimbabwe to the Indian Ocean. Confusion reigns in Mozambique in the aftermath of the devastating civil war. And in a country reputed to be the poorest on earth, the government can do little to control the flood of border jumpers in both directions: Mozambicans enter Zimbabwe to sell everything from guns to clothes donated by aid agencies and Zimbabweans enter Mozambique in search of land to till.
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  • Date Issued: 1995

Inorganic Chemistry 2: PAC 321

  • Authors: Ajibade, P A , Purcell, W
  • Date: 2012-01
  • Language: English
  • Type: Examination paper
  • Identifier: vital:17822 , http://hdl.handle.net/10353/d1010375
  • Description: Inorganic Chemistry 2: PAC 321, degree examination January 2012.
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  • Date Issued: 2012-01

The African coelacanth genome provides insights into tetrapod evolution:

Monitoring the oceanic flow between Africa and Antarctica: report of the first Good Hope cruise

  • Authors: Ansorge, Isabelle J , Speich, S , Lutjeharms, Johan R E , Goni, G J , Rautenbach, C J de W , Froneman, P William , Rouault, M , Garzoli, S
  • Date: 2005
  • Language: English
  • Type: Article
  • Identifier: vital:6832 , http://hdl.handle.net/10962/d1007568
  • Description: The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004.
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  • Date Issued: 2005

Between a cushion and a risky conversation: ARTS LOUNGE reviewed

  • Authors: Baasch, Rachel M
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/147703 , vital:38662 , https://doi.org/10.1080/00043389.2011.11877155
  • Description: On the fringe of the National Arts Festival, at a point of transition between Rhodes University campus and the commercial side of Grahamstown, the walls of a former home and former horse-stable, now a research house, reverberate with the strain of cross-disciplinary, site-specific collaboration. The ARTS LOUNGE made its first official appearance at the Grahamstown National Arts Festival (ViPPA Research Center, Rhodes University) from 30 June to 9 July 2011. The ten-day event was organised by the Visual and Performing Arts of Africa Research (ViPPA) team in collaboration with musicians, artists, writers, performers and members of the public.
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  • Date Issued: 2017

Non-aggregated lipophilic water-soluble tin porphyrins as photosensitizers for photodynamic therapy and photodynamic antimicrobial chemotherapy:

  • Authors: Babu, Balaji , Soy, Rodah C , Mack, John , Nyokong, Tebello
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/158241 , vital:40165 , DOI: 10.1039/d0nj01564d
  • Description: Two readily synthesized water-soluble Sn(IV) porphyrins have been prepared with quaternized pyridyl nitrogens and 2-naphthalato trans-axial ligands. Methyl and hexyl groups were attached to the quaternized nitrogens to form lipophilic dyes with high singlet oxygen quantum yields (ca. 0.90) and unusually long triplet state lifetimes. The dyes exhibit good photodynamic activity against MCF-7 cells with IC50 values of 14.3 and 8.5 μM, respectively. The hexyl quaternized dye exhibited a 9.69 log reduction value (0.5 μM) towards S. aureus under illumination for 90 min (250 mW cm−2). The results demonstrate that this set of structural modification strategies for photosensitizer dyes merits further in depth study.
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  • Date Issued: 2020

Vice-Chancellor's welcoming address 2011

  • Authors: Badat, Saleem
  • Date: 2011
  • Language: English
  • Type: text
  • Identifier: vital:7591 , http://hdl.handle.net/10962/d1006582
  • Description: From introduction: The Purposes of a University. So permit me to spend a few minutes on the meaning of a university and the three purposes. Rhodes University exists to serve. The first purpose is to produce knowledge, so that we can advance understanding of our natural and social worlds and enrich our scientific and cultural heritage. This means that we ‘test the inherited knowledge of earlier generations’, we dismantle the mumbo jumbo that masquerades for knowledge, we ‘reinvigorate’ knowledge, and we share our findings with others. As a university, our second purpose is to disseminate knowledge and to develop your minds. Our goal is to ensure that you can think imaginatively, ‘effectively and critically’; that you ‘achieve depth in some field of knowledge’; that you can critique ideas and views and construct alternatives, and that you can communicate cogently, orally and in writing. Our final purpose as a university is to undertake community engagement, whether this is as part of academic courses or your voluntary participation in community projects organized by our Community Engagement Office.
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  • Date Issued: 2011

Rhodes University : into 2007 and beyond

  • Authors: Badat, Saleem
  • Date: 2007
  • Subjects: Rhodes University
  • Language: English
  • Type: text
  • Identifier: vital:7655 , http://hdl.handle.net/10962/d1015783
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  • Date Issued: 2007

VC's welcome at the Rhodes University house committees and sub-wardens workshop

  • Authors: Badat, Saleem
  • Date: 2013-01-30
  • Language: English
  • Type: Text
  • Identifier: vital:7914 , http://hdl.handle.net/10962/d1016464
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  • Date Issued: 2013-01-30

Biological activity of extracellular and intracellular polysaccharides from Pleurotus tuber-regium hybrid and mutant strains

  • Authors: Bamigboye, Comfort O , Oloke, Julius K , Dames, Joanna Felicity
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/69056 , vital:29376 , http://pubs.sciepub.com/jfnr/4/7/2/
  • Description: Publisher version , Pleurotus tuber-regium (Fr.) Singer (1951) is a unique sclerotium-forming edible and medicinal mushroom. Interestingly, both the sclerotium and mushroom are edible and are often used for curing various ailments. Previous studies have focused on the antimicrobial and antioxidant activity of the extracellular polysaccharide (EPS) from wild P. tuber-regium. There has been no report on the intracellular polysaccharide (IPS) of the wild mycelia, likewise there is very meager information on the improvement of the perceived potentials of P. tuber-regium. This research study analysed the EPS and IPS fractions of P. tuber-regium hybrid and mutant strains. The antimicrobial potential of the IPS and EPS fractions, their scavenging activity on 1, 1-diphenyl–2picryhydrazyl (DPPH) and Hydroxyl radicals were also determined. Both IPS and EPS fractions of P. tuber-regium hybrids and mutants showed increased DPPH and hydroxyl scavenging activity over the wild P. tuber-regium with an EC50 mostly 1 mg/ml. The antimicrobial activity of the IPS from a mutant strain had an IC50 of 15.6 mg/ml compared to the wild type (18.75 mg /ml). This study showed that selected mutant and hybrids of P. tuber-regium had increased radical scavenging activity indicating potentially increased biological activity that could offer increased benefit as a neutraceutical.
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  • Date Issued: 2016

Multivariate analysis of honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae) of the northeastern and southern regions of Algeria.

  • Authors: Barour, C , Tahar, A , Radloff, Sarah E , Hepburn, H Randall
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451976 , vital:75092 , https://hdl.handle.net/10520/EJC32628
  • Description: Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the northeastern and southern regions (ecological-climatological zones) of Algeria, from 36°55' to 32°25'N and 3°39' to 8°22'E. Three morphoclusters were identified by using principal components and linear discriminant analyses. The bees are identified as Apis mellifera intermissa Buttel-Reepen.
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  • Date Issued: 2005

Age, growth and reproduction of largemouth bass, Micropterus salmoides, in Lake Manyame, Zimbabwe

  • Authors: Beamish, C A , Booth, Anthony J , Deacon, N
  • Date: 2005
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/446770 , vital:74559 , https://doi.org/10.1080/15627020.2005.11407310
  • Description: A total of 478 largemouth bass, Micropterus salmoides (Lacépède, 1802), was sampled between September 1997 and July 2001 using hook-and-line in Lake Manyame, a water supply reservoir situated outside Harare, Zimbabwe. Male fish dominated the samples, possibly an effect of aggressive behaviour towards the sampling gear used. Ages, determined from sectioned sagittal otoliths, ranged from one to nine years with 94% of the sample being between one and four years of age. An annulus was deposited in late-winter/early spring. Female fish, despite being the largest fish sampled, were found to grow at a significantly slower rate than males. Growth was modelled with the von Bertalanffy model as L(t)=37.22(1–exp(–0.66t)) cm SL for males, and L(t) = 48.16(1–exp(–0.41t)) cm SL for females. All fish matured after one year, thereafter they spawned over a four-month period between July and October. Reproductive activity peaked in August. Largemouth bass has successfully colonized freshwater bodies in southern Africa where it has been introduced, causing significant ecological damage to the indigenous ichthyofauna. Given its ability to grow to a large size, and live to an old age and to breed successfully, further introductions should be viewed with extreme caution.
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  • Date Issued: 2005

First assessment of estuarine space use and home range of juvenile white steenbras, Lithognathus lithognathus

  • Authors: Bennett, Rhett H , Childs, Amber-Robyn , Cowley, Paul D , Næsje, T F , Thorstad, Eva B , Økland, F
  • Date: 2011
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/447517 , vital:74653 , https://doi.org/10.1080/15627020.2011.11407476
  • Description: The spatial dynamics and home range sizes of early juvenile white steenbras (Lithognathus lithognathus Cuvier, 1829) in the permanently open Great Fish Estuary, South Africa, were assessed using acoustic telemetry. Seven individuals (154–184 mm fork length) tagged with acoustic transmitters spent the majority of their time in the mesohaline to oligohaline regions of the estuary, between five and seven kilometres from the mouth. Mean home range size was small (97 399 ± 22 557 m2, mean ± S.D.) relative to the size of the estuary (approx. 1 360 000m2). Mean length of the estuary used by an individual was 1707m(±S.D.=1663 m). The fish were highly resident within the estuary, and showed fidelity towards their site of capture.
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  • Date Issued: 2011

Procedures for the resolution of labour disputes

  • Authors: Bezuidenhout, G
  • Date: 1988-08-04
  • Subjects: Labour disputes -- South Africa , Labour movement -- South Africa , Labour unions -- South Africa
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/76936 , vital:30643
  • Description: After SACCOLA's expulsion from the International Organization of Employers in 1983 the committee decided to explore areas of domestic activity consistent with its objectives of discussing employer views on labour affairs, and representing these views where agreement amongst employers existed. As the National Manpower Commission had shortly afterwards published a lengthy report dealing, inter alia, with the role of the Industrial Court and the definition of the unfair labour practice concept, SACCOLA set up a working party to see if employer consensus could be achieved on these issues. SACCOLA succeeded in agreeing a 18 page document, which was submitted to the Department of Manpower on 28 August 1984. This was subsequently acknowledged by the Director General of Manpower to have been one of the most comprehensive reactions to this report. In his reaction to the report, however, Dr Van der Merwe noted that legislative change would be greatly facilitated by labour/employer agreement, and he therefore suggested that SACCOLA should discuss its proposals with union federations.
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  • Date Issued: 1988-08-04

"The French Imperial Nation-State":

  • Authors: Bischoff, Paul, 1954-
  • Date: 2005
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/161376 , vital:40621
  • Description: Book Review. The French Imperial Nation-State. By G Wilder (2005).
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  • Date Issued: 2005

Nesting success and survival rates of suburban Olive Thrushes (Turdus olivaceus olivaceus).

  • Authors: Bonnevie, Bo T
  • Date: 2007
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/448299 , vital:74720 , https://doi.org/10.2989/OSTRICH.2007.78.2.19.99
  • Description: Adult survival rates of suburban Olive Thrushes (Turdus olivaceus) were estimated from the proportion of adults and juveniles in mist-net samples from the Eastern Cape and Western Cape provinces of South Africa. These survival rates were compared to an estimate from recovery data. Reproductive rate, clutch size, nesting success and survival rate of dependent fledglings were estimated from breeding records in the Eastern Cape. These data were used to estimate survival rate of independent fledglings. The estimated adult survival rate in this region was high and the clutch size was small, compared to those of the Blackbird (Turdus merula) in Europe. Dispersal patterns from recapture and recovery data, and the relatively low survival rates of juvenile birds, suggest that fledglings are most vulnerable when they reach independence and leave their natal territories.
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  • Date Issued: 2007
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