List of Titles

The distribution, habitat, diet and forensic significance of the scarab Frankenbergerius forcipatus (Harold, 1881) (Coleoptera : Scarabaeidae)

- Midgley, John M, Collett, Isabel J, Villet, Martin H

Authors: Midgley, John M , Collett, Isabel J , Villet, Martin H
Date: 2012
Language: English
Type: Article
Identifier: vital:6842 , http://hdl.handle.net/10962/d1010992
Description: Records of African beetles feeding on carrion are scattered and incomplete, but important to forensic entomology. Thirty-three specimens of Frankenbergerius forcipatus (Harold, 1881) were found on carrionnear Grahamstown, Eastern Cape, South Africa, providing new insight into the distribution (hills and mountains), habitat (fynbos and forest), biology (generalist on decaying material) and forensic significance (wet-decay, late opportunist) of the species.
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Date Issued: 2012

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The use of response surface methodology to evaluate the impact of level 2 SUPAC–IR changes on the in vitro release of metronidazole and ranitidine from a fixed-dose combination tablet

- King’ori, Loti D, Walker, Roderick B

Authors: King’ori, Loti D , Walker, Roderick B
Date: 2012
Language: English
Type: text , Article
Identifier: vital:6391 , http://hdl.handle.net/10962/d1006313
Description: The purpose of this study was to evaluate the effect of different levels of disintegrant (croscarmellose sodium, CCS), binder (polyvinylprrolidone K30, PVP–K30), and lubricant (magnesium stearate) on the in vitro release of metronidazole (MTZ) and rantidine (RTD) from a solid oral fixed-dose combination tablet. The excipient levels investigated were Level 2 changes in component and composition described in the Scale-Up and Post Approval Changes for Immediate Release (SUPAC–IR) guidance (1). Batches of tablets (1000 units) were manufactured by wet granulation using a Saral high-shear mixer granulator and a Manesty B3B rotary tablet press. Weight uniformity, friability, and disintegration of all tablets were assessed, and all batches complied with compendial specifications. The amount of drug released (Q) at ten minutes was dependent on the levels of CCS in the formulation, and the effect of PVP–K30 and magnesium stearate was dependent on the levels of CCS. Synergistic interactions between independent variables were observed for the Q10 value for RTD, whereas PVP–K30 and magnesium stearate exhibited an antagonistic effect on the Q10 values for MTZ and RTD. The use of response surface methodology facilitated an investigation into the effect of Level 2 component and composition changes, as described in SUPAC–IR, on the in vitro release of MTZ and RTD from a fixed-dose combination (FDC) solid oral dosage form (SODF).
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Date Issued: 2012

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Treating complex post-traumatic stress disorder following childhood neglect, sexual abuse and revictimisation : interpretative reflections on the case of Khuselwa

- Padmanabhanunni, A, Edwards, David J A

Authors: Padmanabhanunni, A , Edwards, David J A
Date: 2012
Language: English
Type: Article
Identifier: vital:6233 , http://hdl.handle.net/10962/d1007783
Description: This paper describes the psychological assessment and treatment process with Khuselwa, a South African adolescent survivor of multiple sexual traumas presenting with complex post-traumatic stress disorder (PTSD). The paper identifies some of the common barriers encountered by practitioners in delivering treatments in local contexts and highlights the role of external safety and stability and social support in providing a vehicle for change and a basis for overcoming the psychological handicaps reinforced by repeated and multiple traumas and chronic neglect.
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Date Issued: 2012

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Treatment of post traumatic stress disorder following an armed robbery : a case study testing the transportability of trauma-focused cognitive-behavioural therapy to urban Africans

- Drake, B, Edwards, David J A

Authors: Drake, B , Edwards, David J A
Date: 2012
Language: English
Type: Article
Identifier: vital:6225 , http://hdl.handle.net/10962/d1007775
Description: John, an urban African male who developed post traumatic stress disorder (PTSD) following an armed robbery at the petrol station where he worked, was treated with 12 sessions of Trauma-focused cognitive behaviour therapy. Intervention involved a combination of psycho-education, prolonged imaginal exposure, cognitive restructuring and behavioural assignments. This article is a systematic case study of his treatment which included a comprehensive narrative and tracking of progress by means of the Post traumatic Diagnostic Scale. John responded well to the treatment, finding it acceptable and credible and remained free of PTSD symptoms at 15 months follow up. It is argued, based on the principles of Elliott’s Hermeneutic Single Case Efficacy Design, that there is evidence from within the narrative that it was the treatment that led to remission of symptoms. This case study demonstrates the cognitive, emotional and behavioural processes underlying John’s PTSD, which fits with those extensively described in the research literature, and that this evidence-based treatment developed in a westernised context is transportable to work with urban Africans.
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Date Issued: 2012

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3000 miles from home: a new Gastrosericus baobabicus Pulawski, 1995 (Hymenoptera, Larridae) distribution record highlights that the Sahel has a distinct entomofaunal signature

- Clitheroe, Crystal-Leigh, Villet, Martin H

Authors: Clitheroe, Crystal-Leigh , Villet, Martin H
Date: 2011
Language: English
Type: Article
Identifier: vital:6846 , http://hdl.handle.net/10962/d1011099
Description: [from introduction] On October 30, 1953, an unidentified female wasp (Fig. 1) was collected from ‘Belet Uen, Somaliland’ (= Beledweyne, 4°44’N 45°12’E), situated in the valley of the Shebelle River, HiraanProvince,Somalia. It was deposited in the aculeate Hymenoptera collection of the Albany Museum, Grahamstown by D. Greathead prior to 1968. Apart from the words ‘Somaliland’ and ‘Desert Locust Survey’ the label is handwritten and the collector’snameis not recorded. Greathead’s sister, S. Gess (Albany Museum), deciphered the label and stated that he had worked for the Desert Locust Survey, investigating the natural enemies of locusts and had been in Somalia (then Somaliland) at that time (Murphy & Cock 2007). The specimen was sent in 2004 by F. Gess to W. Pulawski, who determined it as Gastrosericus baobabicus Pulawski, 1995. Gastrosericus species prey on spiders and a variety of small insects (Pulawski 1995), including Orthoptera (Krombein & Pulawski 1986), so it is likely that Greathead collected the specimen in connection with his interest in the insect enemies of Acridoidea (Orthoptera) (Greathead 1962).
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Date Issued: 2011

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Above ground woody community attributes, biomass and carbon stocks along a rainfall gradient in the savannas of the central lowveld, South Africa

- Shackleton, Charlie M, Scholes, Robert J

Authors: Shackleton, Charlie M , Scholes, Robert J
Date: 2011
Language: English
Type: Article
Identifier: vital:6658 , http://hdl.handle.net/10962/d1007079
Description: Enumeration of carbon stocks at benchmark sites is a necessary activity in assessing the potential carbon sequestration and possible generation of credits through restoration of intensively impacted sites. However, there is a lack of empirical studies throughout much of the savannas of sub-Saharan Africa, including South Africa. We report an estimation of species specific and site biomass and carbon stocks, and general vegetation structural attributes from three protected areas along a rainfall gradient in the central lowveld, South Africa. Estimates of biomass and carbon stocks were effected through destructive sampling to establish locally derived allometric equations. There was a gradient of increasing woody density, height of the canopy, number of species, density of regenerative stems and a greater proportion of stems in small size classes from the arid locality to the mesic locality, with the semi-arid locality being intermediate. The proportion of spinescent species decreased with increasing rainfall. The mesic locality was significantly more woody than either the arid or semi-arid sites, having double the biomass, four times the density and 40% higher basal area. Above ground carbon pools were also higher; carbon stocks were approximately 9 t/ha for the arid and semi-arid sites and 18 t/ha for the mesic site.
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Date Issued: 2011

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Culture as a discursive resource opposing legal abortion

- Macleod, Catriona I, Sigcau, Nomakhosi, Luwaca, Pumeza

Authors: Macleod, Catriona I , Sigcau, Nomakhosi , Luwaca, Pumeza
Date: 2011
Language: English
Type: Article
Identifier: vital:6293 , http://hdl.handle.net/10962/d1014721 , http://dx.doi.org/10.1080/09581596.2010.492211
Description: The notion of ‘culture’ features in the abortion literature to explicate, first, contestation of the meaning of abortion (as in the ‘culture wars’ about abortion), second, the normalisation of abortion in certain countries (as in ‘abortion culture’), third, the response of women to abortion within a particular social milieu and fourth, cross-cultural variability in attitudes towards and experiences of abortion. What is missing is an exploration of how ‘culture’ may be deployed as a discursive resource to oppose legal abortion. In this article, we report on a study conducted in a rural area of South Africa. We conducted focus group discussions utilising hypothetical vignettes to stimulate talk. Although, inconsistencies were evident in participants’ talk, in the context of cultural discussions, abortion was constructed as killing and inevitably destructive of cultural values and traditions. Abortion was equated with colonialist interventions and as something that should be opposed in the preservation of culture. Furthermore, cultural opposition to abortion was rooted in fears around the breakdown of gendered and generational power relations. Examples of how culture may be used in everyday interactions to induce shame and negative experiences are also discussed.
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Date Issued: 2011

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Dimethylglyoxime based ion-imprinted polymer for the determination of Ni(II) ions from aqueous samples

- Rammika, M, Darko, G, Tshentu, Z, Sewry, J D, Torto, N

Authors: Rammika, M , Darko, G , Tshentu, Z , Sewry, J D , Torto, N
Date: 2011
Language: English
Type: Article
Identifier: vital:6590 , http://hdl.handle.net/10962/d1004173
Description: A Ni(II)-dimethylglyoxime ion-imprinted polymer {Ni(II)-DMG IIP} was synthesised by the bulk polymerisation method. The morphology of the Ni(II)-DMG IIP and non-imprinted polymer were observed by scanning electron microscopy and the chemical structures were evaluated by infrared spectroscopy. Selectivity of the Ni(II)-DMG IIP was studied by analysing, using an inductively coupled plasma-optical emission spectrometer, for Ni(II) ions that were spiked with varying concentrations of Co(II), Cu(II), Zn(II), Pd(II), Fe(II), Ca(II), Mg(II), Na(I) and K(I) in aqueous samples. The studies revealed Ni(II) recoveries ranging from 93 to 100% in aqueous solutions with minimal interference from competing ions. Enrichment factors ranged from 2 to 18 with a binding capacity of 120 μg∙g−1. Co(II) was the only ion found to slightly interfere with the determination of Ni(II). Selectivity studies confirmed that the Ni(II)-DMG IIP had very good selectivity, characterised by %RSD of less than 5%. The limits of detection and quantification were 3x10-4 μg∙mℓ−1 and 9x10-4 μg∙mℓ−1, respectively. The accuracy of the method was validated by analysing a custom solution of certified reference material (SEP-3) and the concentration of Ni(II) obtained was in close agreement with the certified one. The Ni(II)-DMG IIP was successfully employed to trap Ni(II) ions from a matrix of sea, river and sewage water. It is believed that the Ni(II)-DMG IIP has potential to be used as sorbent material for pre-concentration of Ni(II) ions from aqueous solutions by solid-phase extraction.
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Date Issued: 2011

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Diverse pollination systems of the twin-spurred orchid genus Satyrium in African grasslands

- Johnson, S.D, Peter, C.I, Ellis, A.G, Boberg, E, Botes, C, Van der Niet, T

Authors: Johnson, S.D , Peter, C.I , Ellis, A.G , Boberg, E , Botes, C , Van der Niet, T
Date: 2011
Language: English
Type: Article
Identifier: vital:6558 , http://hdl.handle.net/10962/d1006025 , http://dx.doi.org/10.1007/s00606-010-0411-1
Description: The large terrestrial orchid genus Satyrium underwent evolutionary radiations in the Cape floral region and the grasslands of southern and eastern Africa. These radiations were accompanied by tremendous diversification of the unusual twin-spurred flowers that characterize the genus, but pollination data required to interpret these patterns of floral evolution have been lacking for grassland species in the genus. Here we document pollinators, nectar properties, and levels of pollination success for 11 grassland Satyrium species in southern and south-central Africa. Pollinators of these species include bees, beetles, butterflies, hawkmoths, noctuid moths, long-proboscid flies, and sunbirds. Most species appear to be specialized for pollination by one functional pollinator group. Long-proboscid fly pollination systems are reported for the first time in Satyrium (in S. macrophyllum and a high-altitude form of S. neglectum). Floral morphology, especially spur length and rostellum structure, differs markedly among plants with different pollinators, while nectar volume, concentration, and sugar composition are fairly uniform across species. Most taxa exhibited high levels of pollination success (>50% of flowers pollinated), a trend that can be attributed to the presence of nectar in the twin spurs.
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Date Issued: 2011

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Does the growth of structure affect our dynamical models of the Universe? The averaging, backreaction, and fitting problems in cosmology

- Clarkson, C, Ellis, G, Larena, Julien, Umeh, O

Authors: Clarkson, C , Ellis, G , Larena, Julien , Umeh, O
Date: 2011
Language: English
Type: Article
Identifier: vital:6791 , http://hdl.handle.net/10962/d1006944
Description: Structure occurs over a vast range of scales in the Universe. Our large-scale cosmological models are coarse-grained representations of what exists, which have much less structure than there really is. An important problem for cosmology is determining the influence the small-scale structure in the Universe has on its large-scale dynamics and observations. Is there a significant, general relativistic, backreaction effect from averaging over structure? One issue is whether the process of smoothing over structure can contribute to an acceleration term and so alter the apparent value of the cosmological constant. If this is not the case, are there other aspects of concordance cosmology that are affected by backreaction effects? Despite much progress, this 'averaging problem' is still unanswered, but it cannot be ignored in an era of precision cosmology, for instance it may affect aspects of baryon acoustic oscillation observations.
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Date Issued: 2011

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Elucidation of the complex Baylis-Hillman reaction of 3-methoxy-2-nitrobenzaldehyde with methyl vinyl ketone

- Idahosa, Kenudi C, Molefe, Duduzile M, Pakade, Vusumzi E, Brown, Michael E

Authors: Idahosa, Kenudi C , Molefe, Duduzile M , Pakade, Vusumzi E , Brown, Michael E
Date: 2011
Language: English
Type: Article
Identifier: vital:6574 , http://hdl.handle.net/10962/d1004137
Description: DABCO-catalyzed reaction of 3-methoxy-2-nitrobenzaldehyde with methyl vinyl ketone (MVK) affords a mixture of products, comprising the ‘normal’ Baylis-Hillman adduct, theMVKdimer and a pair of diastereomeric bis-(MVK)Baylis-Hillman adducts. 1HNMRspectroscopy-based kinetic studies have provided clear insights into the competing pathways and product distribution in this complex reaction.
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Date Issued: 2011

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Energy versus angular momentum in black hole binaries

- Damour, T, Nagar, A, Pollney, D, Reisswig, C

Authors: Damour, T , Nagar, A , Pollney, D , Reisswig, C
Date: 2011
Language: English
Type: Article
Identifier: vital:6792 , http://hdl.handle.net/10962/d1006946
Description: Using accurate numerical-relativity simulations of (nonspinning) black-hole binaries with mass ratios 1∶1, 2∶1, and 3∶1, we compute the gauge-invariant relation between the (reduced) binding energy E and the (reduced) angular momentum j of the system. We show that the relation E(j) is an accurate diagnostic of the dynamics of a black-hole binary in a highly relativistic regime. By comparing the numerical-relativity ENR(j) curve with the predictions of several analytic approximation schemes, we find that, while the canonically defined, nonresummed post-Newtonian–expanded EPN(j) relation exhibits large and growing deviations from ENR(j), the prediction of the effective one body formalism, based purely on known analytical results (without any calibration to numerical relativity), agrees strikingly well with the numerical-relativity results.
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Date Issued: 2011

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Evaluating the Wald entropy from two-derivative terms in quadratic actions

- Brustein, R, Gorbonos, D, Hadad, M, Medved, A J M

Authors: Brustein, R , Gorbonos, D , Hadad, M , Medved, A J M
Date: 2011
Language: English
Type: Article
Identifier: vital:6816 , http://hdl.handle.net/10962/d1004326
Description: We evaluate the Wald Noether charge entropy for a black hole in generalized theories of gravity. Expanding the Lagrangian to second order in gravitational perturbations, we show that contributions to the entropy density originate only from the coefficients of two-derivative terms. The same considerations are extended to include matter fields and to show that arbitrary powers of matter fields and their symmetrized covariant derivatives cannot contribute to the entropy density. We also explain how to use the linearized gravitational field equation rather than quadratic actions to obtain the same results. Several explicit examples are presented that allow us to clarify subtle points in the derivation and application of our method.
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Date Issued: 2011

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Evaluation of the kinetics and mechanism of drug release from Econazole nitrate nanosponge loaded Carbapol Hydrogel

- Sharma, Renuka, Walker, Roderick B, Pathak, Kamla

Authors: Sharma, Renuka , Walker, Roderick B , Pathak, Kamla
Date: 2011
Language: English
Type: text , Article
Identifier: vital:6437 , http://hdl.handle.net/10962/d1006614
Description: The objective of this study was to investigate the mechanism of release of econazole nitrate (EN) nanosponges loaded hydrogel and to compare it with EN hydrogel so as to develop an extended release topical drug delivery system of EN. Nanosponges of EN were prepared using ethyl cellulose and PVA by emulsion solvent evaporation method. On the basis of pharmacotechnical evaluation nanosponges with least particle size of 230.1 nm and good rheological properties were formulated as hydrogel (F1 – F7). In vitro drug release data of EN nanosponges loaded hydrogels in phosphate buffer pH 6.8 and 7.4 when analysed by GraphPad Prism software version 4.0 San Diego, USA best fitted the Makoid-2 Banakar model (R value greater than 0.98). The Korsmeyer-Peppas release exponent (n) ranged between 0.331 – 0.418, which confirmed diffusion as the principle mechanism of drug release. The release mechanism was further confirmed by calculating the ratio of exponents A/B ratio derived from the Kopcha model.
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Date Issued: 2011

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