List of Titles

A yellowwood by any other name: molecular systematics and the taxonomy of Podocarpus and the Podocarpaceae in southern Africa

- Barker, Nigel P, Muller, E M, Mill, R R

Authors: Barker, Nigel P , Muller, E M , Mill, R R
Date: 2004
Language: English
Type: Article
Identifier: vital:6495 , http://hdl.handle.net/10962/d1004488
Description: We briefly review the taxonomic history of the Podocarpaceae, with an emphasis on the recognition of numerous segregate genera out of Podocarpus sensu lato. Despite some controversy over the recognition of these genera, molecular data (DNA sequences) provide evidence that supports this taxonomy. The implications for African Podocarpaceae are discussed. In particular, molecular data support the recognition of Afrocarpus as distinct from Podocarpus. Additional taxonomic problems concerning the possible segregation of Podocarpus milanjianus from P. latifolius are addressed using DNA sequence data from the nuclear internal transcribed spacer 2 (ITS2) region. Results of this are inconclusive, and suggest that alternative DNA-based evidence, such as from AFLPs or microsatellites, may be more informative in resolving such species complexes in African Podocarpus.
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Date Issued: 2004

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Spatial variation in the macrobenthic assemblages of intertidal seagrass along the long axis of an estuary

- Barnes, R S K, Ellwood, M D F

Authors: Barnes, R S K , Ellwood, M D F
Date: 2014-05-29
Language: English
Type: Article
Identifier: vital:6870 , http://hdl.handle.net/10962/d1011513
Description: Invertebrate macrofaunal biodiversity within intertidal seagrass meadows was investigated over a salinity gradient of <5–35 in the Knysna estuarine system (Garden Route National Park, South Africa). Rather than the classic gradual decline in species richness with distance from the mouth there were zones of considerable faunal stability separated by relatively sharp discontinuities. At the point upstream at which salinity regularly falls below 30, the rich, diverse and highly spatially variable downstream faunal assemblage changed to a less rich, less diverse and more uniform one that dominated the upstream stretch without any further upstream reduction in richness. Nevertheless, without loss of overall richness, assemblage composition changed, again rapidly, in the upper region of the upstream stretch to a zone dominated by the microgastropod Hydrobia, which otherwise occurs in the Knysna system only in highly sheltered regions of the downstream stretch where it is also dominant. The upstream faunal assemblage was a subset of that in the marine-influenced downstream region not a different replacing one. Position along the estuarine gradient accounted for 29% of total assemblage variation. Overall faunal abundance declined with distance upstream until the Hydrobia zone where it rose sharply, but there was no evidence of increase in density of those species remaining on putative release from competition.
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An ion-imprinted polymer for the selective extraction of mercury(II) ions in aqueous media

- Batlokwa, Bareki Shima, Chimuka, Luke, Tshentu, Zenixole, Cukrowska, Ewa, Torto, Nelson

Authors: Batlokwa, Bareki Shima , Chimuka, Luke , Tshentu, Zenixole , Cukrowska, Ewa , Torto, Nelson
Date: 2012
Language: English
Type: Article
Identifier: vital:6566 , http://hdl.handle.net/10962/d1004125
Description: A double-imprinted polymer exhibiting high sensitivity for mercury(II) in aqueous solution is presented. Polymer particles imprinted with mercury(II) were synthesised by copolymerising the functional and cross-linking monomers, N’–[3– (Trimethoxysilyl)–propyl]diethylenetriamine (TPET) and tetraethylorthosilicate (TEOS). A double-imprinting procedure employing hexadecyltrimethylammonium bromide (CTAB), as a second template to improve the efficiency of the polymer, was adopted. The imprinted polymer was characterised by FTIR, scanning electron microscopy (SEM) and the average size determined by screen analysis using standard test sieves. Relative selective coefficients (k`) of the imprinted polymer evaluated from selective binding studies between Hg2+ and Cu2+ or Hg2+ and Cd2+ were 10 588 and 3 147, respectively. These values indicated highly-favoured Hg2+ extractions over the 2 competing ions. The results of spiked and real water samples showed high extraction efficiencies of Hg2+ ions, (over 84%) as evaluated from the detected unextracted Hg2+ ions by ICP-OES. The method exhibited a dynamic response concentration range for Hg2+ between 0.01 and 20 μg/mℓ, with a detection limit (LOD, 3σ) of 0.000036 μg/mℓ (36 ng/ℓ) that meets the monitoring requirements for the USA EPA of 2 000 ng/ℓ for Hg2+ in drinking water. Generally, the data (n=10) had percentage relative standard deviations (%RSD) of less than 4%. Satisfactory results were also obtained when the prepared sorbent was applied for the pre-concentration of Hg2+ from an aqueous certified reference material. These findings indicate that the double-imprinted polymer has potential to be used as an efficient extraction material for the selective pre–concentration of mercury(II) ions in aqueous environments.
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Date Issued: 2012

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Dog Latin, Norman Morrissey : book review

- Beard, Margot

Authors: Beard, Margot
Date: 2007
Language: English
Type: Article
Identifier: vital:6115 , http://hdl.handle.net/10962/d1003828
Description: I have only seen one earlier collection of Morrissey's - his slim volume Seasons (1999). Therein he revealed his enjoyment and interest in haiku. Even the two longer poems in that volume were haiku-like, being brief self-contained stanzas grouped under a single title. His new volume, Dog Latin, consists of sixty short poems primarily concerned with man and nature. A number of these are haiku-like in their brevity ("Edgar on Inclusive Fitness," "Setting Ratbane," "Adam Again"), although they too often do not amount to more than post-it like notes. ("This habit / of holding habits to the wind / -me" is the sum total of the poem "Adam Again.") The epigraph to the whole collection is the final stanza of Robert Frost's "The Need of Being Versed in Country Things," which suggests both Morrissey's interest in the apparently unconsidered minutiae of natural objects and beings, and, it would seem, an admiration of Frost's deceptively plain, unmannered style.
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Date Issued: 2007

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Lessons from the dead masters: Wordsworth and Byron in J. M. Coetzee's Disgrace

- Beard, Margot

Authors: Beard, Margot
Date: 2007
Language: English
Type: Article
Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
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Date Issued: 2007

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The effect of fluctuating substrate salinity on the yield and flag leaf photosynthesis of wheat

- Beckett, R P, Drennan, P M, Botha, Christiaan E J

Authors: Beckett, R P , Drennan, P M , Botha, Christiaan E J
Date: 1995
Language: English
Type: Article
Identifier: vital:6501 , http://hdl.handle.net/10962/d1005922
Description: The effects of constant and fluctuating substrate salinity on flag leaf photosynthesis and grain yield of wheat were investigated. Plants exposed to salinity fluctuating around a mean integrated value of 25 mol m-3 NaCl (0-50 mol m-3) and around 50 mol m-3 NaCl (25-75 mol m-3) had yields 36 and 38% higher, respectively, than those receiving the corresponding constant salinity. Plants treated with salinity fluctuating from 50-100 mol m-3 NaCl had a 14% lower yield than those receiving 75 mol m-3 NaCl. Flag leaf photosynthesis did not vary between treatments and during salinity fluctuations, suggesting that differences in flag leaf longevity caused the observed differences in yield. Results suggest plants grown under constant salinity are unlikely to behave as those in field situations, where fluctuating rather than constant salinity occurs.
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Date Issued: 1995

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Surface electrochemistry : structured electrode, synthesis, and characterization

- Bedioui, Fethi, Nyokong, Tebello, Zagal, Jose H

Authors: Bedioui, Fethi , Nyokong, Tebello , Zagal, Jose H
Date: 2012
Language: English
Type: Article
Identifier: vital:6567 , http://hdl.handle.net/10962/d1004126 , http://dx.doi.org/10.1155/2012/405825
Description: From introduction: The aim of this special issue is to show, through recent updated significant examples, how the electrochemical techniques allow the unique characterization of specific properties of micro- and nanostructured materials that offer varied possibilities of uses and the preparation of specific types of ordered materials that take advantage of electrochemical synthetic methods such as structuring nanosized wires and dots, to cite only two examples.
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Date Issued: 2012

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Regional development in South Africa’s West Coast: 'dividends on the process side'?

- Bek, David, Binns, Tony, Nel, Etienne L

Authors: Bek, David , Binns, Tony , Nel, Etienne L
Date: 2005
Language: English
Type: Article
Identifier: vital:6674 , http://hdl.handle.net/10962/d1006648
Description: Academics, policy-makers and consultants have been increasingly focusing upon the 'region' as the crucible of economic development. This regionalist approach places institutions at the centre of the process of stimulating growth. Much debate has been ongoing in academic circles, particularly those inhabited by economic geographers, about the veracity of the regionalist approach and the explanatory power of the terminology associated with it. This paper analyses explicit efforts to engender regional economic development in the West Coast of South Africa. Our empirical evaluation indicates that policy actors have sought to upgrade the institutional infrastructure of the region and that some significant achievements are evident within this realm. However, these achievements are yet to be associated with sustained regional economic takeoff. The paper concludes by asking searching questions about the ability of the regionalist approach to deliver meaningful socio-economic transformation.
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Date Issued: 2005

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The effects of load and gradient on hand force responses during dynamic pushing and pulling tasks

- Bennett, Anthea I, Desai, Sheena D, Todd, Andrew I, Freeland, H

Authors: Bennett, Anthea I , Desai, Sheena D , Todd, Andrew I , Freeland, H
Date: 2008
Language: English
Type: Article
Identifier: vital:6757 , http://hdl.handle.net/10962/d1009459
Description: The limited attention afforded to push/pull activities and the motion phases (initial, sustained and ending) characteristic of these tasks has prompted a research focus in this area. The present study examined biomechanical responses in the form of hand forces during dynamic submaximal trolley pushing and pulling. Participants pushed/pulled loads of 100, 200 and 300 kg on the level (determining impact of load) or pushed 100 kg along a 12° ramp (uphill and downhill- determining impact of gradient). During level exertions significant differences (p<0.05) in hand forces occurred between loads of 100 and 200 kg, and 100 and 300 kg for initial and sustained forces but not ending forces. Values were similar for pushing and pulling at respective loads and motion phases. Strong correlations indicate that initial forces can be used to accurately estimate sustained and ending forces. Importantly, correct technique is essential in force reduction. Forces were highest during uphill initial and sustained phases and the downhill sustained phase. For the initial phase, the forces were highest during uphill pushing (86.5 ± 25.73 N); for the sustained phase, there was no difference between uphill and downhill forces but level forces were significantly lower (18.19 ± 8.09 N) than either of the other two conditions; for the ending phase, the highest forces were produced during downhill pushing (-53.34 ± 13.65N). As sustained forces equaled or exceeded initial forces for uphill and downhill efforts, consideration of sustained forces may be appropriate in determining the inherent potential risk of graded pushing.
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Date Issued: 2008

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New possibilities for research on reef fish across the continental shelf of South Africa

- Bernard, Anthony T F, Gotz, A, Parker, Daniel M, Heyns, Elodie R, Halse, S J, Riddin, N A, Smith, M K S, Paterson, Angus W, Winker, A Henning, Fullwood, L, Langlois, T J, Harvey, E S

Authors: Bernard, Anthony T F , Gotz, A , Parker, Daniel M , Heyns, Elodie R , Halse, S J , Riddin, N A , Smith, M K S , Paterson, Angus W , Winker, A Henning , Fullwood, L , Langlois, T J , Harvey, E S
Date: 2014
Language: English
Type: Article
Identifier: vital:6971 , http://hdl.handle.net/10962/d1014566
Description: [From introduction] Subtidal research presents numerous challenges that restrict the ability to answer fundamental ecological questions related to reef systems. These challenges are closely associated with traditional monitoring methods and include depth restrictions (e.g. safe diving depths for underwater visual census), habitat destruction (e.g. trawling), mortality of target species (e.g. controlled angling and fish traps), and high operating costs (e.g. remotely operated vehicles and large research vessels. Whereas many of these challenges do not apply or are avoidable in the shallow subtidal environment, the difficulties grow as one attempts to sample deeper benthic habitats. This situation has resulted in a paucity of knowledge on the structure and ecology of deep water reef habitats around the coast of South Africa and in most marine areas around the world. Furthermore, the inability to effectively survey deep water benthic environments has limited the capacity of researchers to investigate connectivity between shallow and deep water habitats in a standardised and comparable fashion.
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Date Issued: 2014

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The use of archaeological and ethnographical information to supplement the historical record of the distribution of large mammalian herbivores in South Africa

- Bernard, Ric T F, Parker, Daniel M

Authors: Bernard, Ric T F , Parker, Daniel M
Date: 2006
Language: English
Type: Article
Identifier: vital:6914 , http://hdl.handle.net/10962/d1011877
Description: Introduction: The introduction of animal taxa to areas where they do not naturally occur has the potential to damage severely the native fauna and flora. Introductions, both accidental and intentional, to Australia, New Zealand, Marion Island and other oceanic islands provide spectacular examples of this.1,2 Non-native mammalian herbivores often become invasive in the absence of their natural predators2 and their impact on vegetation, which may include alterations to plant species composition, structure and diversity, is exaggerated, especially if the vegetation has evolved in the absence of similar herbivores.3,4 This influence is not limited to the direct consequence for the vegetation and there may be a cascade effect on ecosystem functioning through, for example, a decline in the amount of available forage for indigenous herbivores,3 a reduction in the breeding efficiency of birds that rely on the vegetation,5,6 and a negative effect on carbon storage by transforming stands of dense vegetative cover to open savannah like systems.7 Nor are these outcomes restricted to non-native herbivores; the re-introduction of a species, such as the elephant (Loxodonta africana), to areas from which it has been absent for many years may have similar consequences.8–11 Additional problems associated with the uncontrolled movement of large mammals include the transmission of disease, such as brucellosis in the United States,3 and a threat to the genetic integrity of a species through hybridization.12 It is thus clear that deliberate introductions of herbivores to areas where they do not naturally occur may not be sound conservation practice.
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Date Issued: 2006

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Those merry, tinkling, tuneful bells : handbells in Victorian Grahamstown with a note on bell ringing at Grahamstown Cathedral

- Berning, J M

Authors: Berning, J M
Date: 2003
Language: English
Type: Article
Identifier: vital:6993 , http://hdl.handle.net/10962/d1012420
Description: [From the introduction]: The idea of using sets of small bells tuned to particular notes in order to produce music is very old. There are illustrations of slung bells being played in this way from the 11th and 12th centuries. Bell ringers in England date the sue of sets of tuned and hand-held bells from as early as the 16th century though it seems that the modern handbell may have come into existence in the early 18th century. Such bells were used by tower bell ringers as convenient practice devices for change ringing. The ringing of tunes on handbells became popular in the 18th century and reached its heyday in the latter half of the 19th century. In England tune ringing was especially popular in the north and major competitions had their centre at Manchester. Special trains were run to competitions there and bands, ringing up to 200 bells, could find their skills tested on extracts from Mozart's Don Giovanni. World War I and the spread of alternative media of entertainment like radio put an end to ringing on this scale. , This publication marked the 150th Anniversary of the Diocese of Grahamstown. Michael Berning was a member of the Rhodes University Library staff from 1965 until his retirement in 1997. He was Tower Captain of the Grahamstown Cathedral during the 1980s.
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Date Issued: 2003

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